<PAGE>
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
 
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
 
                            ------------------------
 
                                   FORM 10-K
 
                ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF
                      THE SECURITIES EXCHANGE ACT OF 1934
 
<TABLE>
<S>                                    <C>
     FOR THE FISCAL YEAR ENDED               COMMISSION FILE NUMBER
        SEPTEMBER 30, 1996                           0-22248
</TABLE>
 
                            ------------------------
 
                       GASONICS INTERNATIONAL CORPORATION
               (Exact name of Registrant as specified in charter)
 
<TABLE>
<S>                              <C>
           DELAWARE                   94-2159729
(State or other jurisdiction of    (I.R.S. Employer
incorporation or organization)    Identification No.)
</TABLE>
 
                              2540 Junction Avenue
                           San Jose, California 95134
                                 (408) 325-1200
    (ADDRESS, INCLUDING ZIP CODE, AND TELEPHONE NUMBER, INCLUDING AREA CODE,
              OF REGISTRANT COMPANY'S PRINCIPAL EXECUTIVE OFFICES)
 
          Securities registered pursuant to Section 12(b) of the Act:
                                      NONE
 
          Securities registered pursuant to Section 12(g) of the Act:
                                  COMMON STOCK
 
    Indicate by check mark whether the Registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
Registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days. Yes _X_ No ____
 
    Indicate by check mark if disclosure of delinquent filers pursuant to Item
405 of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by references in Part III of the Form 10-K or any amendment to this
Form 10-K. /X/
 
    The aggregate market value of the voting stock held by non-affiliates of the
Registrant, based on the closing price of the Common Stock on December 17, 1996,
as reported on The Nasdaq National Market was approximately $114,315,000. Shares
of Common Stock held by each officer and director and by each person who owns 5%
or more of the outstanding Common Stock have been excluded from this computation
in that such persons may be deemed to be affiliates. This determination of
affiliate status is not necessarily a conclusive determination for other
purposes.
 
    As of December 17, 1996, the Registrant had outstanding 13,479,945 shares of
Common Stock.
 
                      DOCUMENTS INCORPORATED BY REFERENCE
 
1.  Portions of the Registrant's Annual Report to Stockholders for the fiscal
    year ended September 30, 1996 are incorporated into Parts II and IV of this
    Report on Form 10-K.
 
2.  Portions of the Registrant's Proxy Statement for the Annual Meeting of
    Stockholders to be held on March 3, 1997 are incorporated by reference into
    Part III of this Report on Form 10-K.
 
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
<PAGE>
                                     PART I
 
ITEM 1.  BUSINESS
 
THE COMPANY
 
    GaSonics International Corporation ("GaSonics" or the "Company") is a
leading developer and supplier of a portfolio of products and services used in
the fabrication of advanced integrated circuits ("ICs") and flat panel displays
("FPDs"). The Company is one of the world's leading suppliers of photoresist
removal equipment. The Company's products consist of photoresist removal
systems, residual removal systems, isotropic etch systems and high pressure
furnaces for the semiconductor industry and low pressure chemical vapor
deposition ("LPCVD") for the flat panel display industry. The Company's
photoresist removal, residual removal and isotropic etch systems utilize
proprietary downstream plasma processing technology to increase yields in the
manufacture of advanced ICs. The Company markets and sells its products to many
leading IC manufacturers worldwide including Intel, Motorola, Samsung, Siemens
and Lucent Technologies.
 
    The Company commenced operations in 1968 and was incorporated in California
in March 1971 as "Atomel Products Corporation." The Company changed its name to
"GaSonics International Corporation" in June 1993 and reincorporated in Delaware
in March 1994. In February 1991, the Company acquired Branson International
Plasma Corporation, a manufacturer of photoresist removal equipment. In August
1995, the Company acquired Tekisco, Ltd. from Kishimoto Sangyo Co. Ltd. of
Tokyo, Japan. Tekisco is a manufacturer of LPCVD equipment for the manufacture
of FPDs. The Company's principal executive offices are located at 2540 Junction
Avenue, San Jose, California 95134. The Company's telephone number is (408)
325-1200 and worldwide website address is http://www.gasonics.com.
 
INDUSTRY BACKGROUND
 
    The worldwide market for advanced ICs and products utilizing such devices
has experienced rapid growth. This growth has caused a corresponding increase in
demand for equipment used to manufacture semiconductors. The fabrication of ICs
requires a large number of complex and repetitive processing steps, including
deposition, photolithography and etch. Deposition is a process in which a layer
of either electrically insulating or electrically conductive material is
deposited on the surface of a wafer. In the photolithography process, device
features are imprinted using a photomask on a light sensitive polymer called
photoresist. After development of the photoresist, etching selectively removes
the deposited material from the surface of the wafer that is not covered by the
imprinted pattern. In advanced IC fabrication, deposition, photolithography and
etch are repeated numerous times in order to layer different materials and
imprint various features on a single wafer and to produce a fully functional IC
device. Prior to processing additional layers on the wafer in the fabrication
process, the residual photoresist from the previous layer must be carefully
removed in order to create a clean and functional foundation for the next layer.
This process is referred to as "photoresist removal" or "ashing."
 
    The fabrication of advanced ICs, which offer increased capabilities, more
power and greater performance, requires increasing numbers of photolithographic
masking layers and corresponding photoresist removal steps. For example, a
typical one megabit Dynamic Random Access Memory chip ("DRAM") requires 11
masking steps, each with a corresponding photoresist removal step. By
comparison, a 64 megabit DRAM is expected to require between 20 and 25 masking
steps, each with a corresponding photoresist removal step. As line geometries,
or feature sizes, of an IC continue to decrease to near 0.25 microns and wafer
cleanliness becomes increasingly important, it is expected that more advanced
and additional ashing steps will be required to prepare the wafer surface for
subsequent masking steps. As a result of these trends, the Company believes that
the number of photoresist removal systems per production line of advanced ICs
will increase.
 
                                       1
<PAGE>
    Historically, photoresist removal was considered a necessary process step
that did not require implementation of advanced technologies. In the 1970s,
photoresist was typically removed by immersing ICs into large liquid chemical
baths ("wet chemistry processing"). In the early 1980's, dry chemistry
processing, which utilizes gases to remove the photoresist, began to replace wet
chemistry processing for those advanced processing steps that wet chemistry
processing was unable to complete or added too many defects (particles). The dry
chemistry processing alternative for photoresist removal has continued to become
more widely used because this alternative is believed to offer significant cost
of ownership savings as compared with wet chemistry processing, especially for
complex ICs with feature sizes of 1.0 microns and below. Wet chemistry
processing also poses certain environmental concerns as a result of risks
associated with chemical storage, handling, disposal and operator safety. In the
fabrication of advanced ICs, wet chemistry processing for photoresist removal is
now typically used only for noncritical cleaning steps after application of a
dry chemistry photoresist removal process. Traditional dry chemistry photoresist
processing involves the creation of plasma and exposure of the wafer to the
plasma in a single chamber in order to remove the residual photoresist. However,
because certain elements of the plasma can cause damage to the wafer, direct
exposure of the wafer to the plasma can result in reduced yield. This damage
becomes increasingly problematic as feature sizes decrease and, at certain
feature sizes, can result in significantly reduced yield.
 
THE GASONICS SOLUTION
 
    In order to address the photoresist removal needs of advanced IC
manufacturers, GaSonics pioneered an advanced dry chemistry processing
technology known as "downstream microwave processing." This technology separates
the creation region of the plasma from exposure to the wafer and shields the
wafer from the elements of the plasma that cause damage to the wafer while still
allowing for the chemical function to take place. As line geometries continue to
decrease and wafer sizes increase, the Company believes that advanced
photoresist removal techniques such as those offered by GaSonics will be
required to manufacture advanced ICs at acceptable yields. The Company believes
that yield, operating costs, throughput, reliability, uptime and system cost all
contribute to an IC manufacturer's total cost of ownership. The Company believes
that downstream microwave processing enables the Company's photoresist removal
systems to offer advanced IC manufacturers a process solution with cost of
ownership savings by increasing yields at current and future line geometries.
GaSonics' removal products are designed as single wafer systems capable of
processing eight-inch wafers, which the Company believes further increases
yields as compared with traditional multiple wafer processing systems.
 
THE GASONICS STRATEGY
 
    In order to maintain its leadership position in advanced dry chemistry
processing equipment for photoresist removal, GaSonics has implemented a
business strategy with the following key elements:
 
    ENHANCE STRATEGIC CUSTOMER RELATIONSHIPS.  The Company believes that its
long-standing relationships with many leading worldwide IC manufacturers such as
Intel, Motorola, Samsung, and Siemens are critical to ensure its position as a
leading supplier of photoresist removal equipment used in the fabrication of
advanced ICs. The Company intends to continue to focus its resources on its key
customers in order to develop the process equipment solutions needed to
manufacture the next generation of ICs and to lower the semiconductor
manufacturer's total cost of ownership for photoresist removal equipment. As
part of this focus, the Company provides dedicated personnel at key customer
facilities. The Company believes that these relationships will enable it to
better understand the needs of its customers, to design new fabrication process
equipment and to position GaSonics as a principal supplier of volume equipment
orders.
 
    FOCUS ON CAPITAL PRODUCTIVITY.  GaSonics is committed to providing its
customers with photoresist removal equipment solutions offering a lower cost of
ownership than many competing products. By increasing yields in the manufacture
of advanced ICs, the Company believes its proprietary downstream
 
                                       2
<PAGE>
microwave processing technology offers customers cost of ownership advantages
over wet chemistry processing and traditional dry chemistry processing. The
Company believes that its technology results in a lower cost of ownership than
wet chemistry technology in the manufacture of advanced ICs due to the higher
costs associated with the use of consumable chemicals in wet chemistry
processing of larger diameter wafers. In addition, the Company believes that its
technology results in better yields than traditional dry chemistry as a result
of the reduced damage and contamination caused to the wafer in the Company's
downstream dry chemistry processing. The Company believes that the increased
yields provided by its systems position GaSonics as a preferred provider of
lower cost of ownership solutions for photoresist removal and other cleaning
applications. In addition, the Company intends to continue to introduce
cost-effective products and product enhancements, such as the Strata, Vertical
High Pressure ("VHP") and Performance Enhancing Platform ("PEP") systems.
 
    CAPITALIZE ON ADVANCED WAFER FABRICATION TRENDS.  Numerous wafer fabrication
lines capable of manufacturing eight-inch wafers with near 0.25 micron line
geometries are currently under construction or have been completed worldwide.
The Company seeks to address the market opportunity for advanced photoresist
removal equipment created by these wafer fabs. At 0.25 micron line geometries,
the Company believes that the yield benefits from dry chemistry processes in
general and GaSonics' downstream processing technology in particular increase
significantly. GaSonics was one of the first companies to target the advanced
photoresist removal market by transitioning from traditional batch processing to
a single wafer design and currently has an installed base of approximately 600
systems in the eight-inch market.
 
    PENETRATE ASIA/PACIFIC MARKET.  The Asia/Pacific market for IC processing
equipment represents more than half of the worldwide market. The Company has
recently been successful in marketing and selling its products to certain
customers in Korea, Singapore, Taiwan and Japan. GaSonics intends to continue to
invest significant resources in order to further penetrate the Asia/Pacific
market, particularly Japan, which has historically been dominated by Japanese
process equipment manufacturers. Japanese suppliers have typically offered
traditional dry chemistry systems which process multiple wafers in a single
batch. Because manufacturers of advanced ICs on larger diameter wafers are
increasingly adopting single wafer processing, the Company believes its single
wafer systems, which incorporate advanced dry chemistry processing techniques,
are particularly well-positioned to compete in Japan. The Company established a
relationship in 1994 with a distributor of semiconductor capital equipment in
Japan for sales of its photoresist removal equipment and has established a
wholly-owned subsidiary in Japan. In addition, the Company has staffed its
Japanese subsidiary to market and sell its high pressure systems and to provide
technical support and applications personnel to enhance the Company's
distributors' ability to sell photoresist removal and cleaning equipment.
 
    TARGET NEW SYSTEMS AND APPLICATIONS.  The Company believes that its strong
customer relationships and technology leadership will enable it to develop new
systems and target new applications. The Company believes that advanced dry
processing equipment will be utilized for certain additional process steps in
the manufacture of advanced ICs as feature sizes continue to decrease. GaSonics
completed the development of three new products, the Strata, the VHP and the PEP
and initial shipments of these systems commenced in April, August, and November
1995, respectively. The Strata system is intended to replace a costly and toxic
wet chemistry process step for the selective etching of certain materials on a
wafer. The VHP system is intended to allow certain customers to extend key
elements of their current fabrication process for up to two additional
generations by using a proprietary high pressure process to reduce exposure to
high temperature. The PEP system is a dual chamber photoresist and residue
removal system designed to increase throughput as compared to single chamber
systems and saves space in the customer's clean room. PEP systems allow a mix
and match option whereby customers can incorporate either photoresist removal,
residue removal or a combination of photoresist removal and residue removal
process chambers, depending on the customers' needs.
 
                                       3
<PAGE>
GASONICS TECHNOLOGY
 
    GaSonics' proprietary microwave downstream processing technology for dry
chemistry processing has been a key element in establishing demand for its
products. The Company believes this technology offers significant advantages
over other dry chemistry processing technologies because it increases yields in
the production of advanced ICs by reducing the amount of damage and
contamination caused to the wafer from the creation of the active gases that
remove the photoresist. The Company believes that older technologies,
particularly wet chemistry processing, offer advantages in the fabrication of
less advanced ICs (1.0 microns or greater) manufactured on smaller wafers (6
inches or less) in facilities where manufacturers continue to rely on older
batch processing techniques.
 
MICROWAVE DOWNSTREAM PROCESSING
 
    Microwave downstream processing technology is a dry chemistry process that
uses elements created by plasma in order to remove photoresist and other
materials on a wafer. In traditional dry chemistry processing, the plasma is
created in the same chamber in which the active gases are exposed to the
photoresist on the wafer. This method typically causes significant damage and
contamination to the wafer because certain elements ("species") that result from
the creation of the plasma react negatively with the materials. In the Company's
products, the plasma is generated in one chamber and, using the Company's
proprietary technology, the active species are separated from the discharge
region and introduced downstream into the wafer processing chamber. The Company
believes the resulting reduction in damage and contamination to the wafer
increases yield and lowers the total cost of ownership of the photoresist
removal process equipment in the fabrication of advanced ICs.
 
    The Company's downstream processing technology incorporates the following
key elements:
 
    - Microwave Frequency--The Company believes that microwave frequency, which
      was introduced by GaSonics in 1986, has become the preferred source for
      the creation of plasma because it produces density which is more efficient
      than the alternative, radio frequency energy. By creating the plasma more
      efficiently, the Company believes its products have higher throughput and
      can operate at lower temperatures than competitive products that utilize
      radio frequency energy.
 
    - Single Wafer Processing--The Company believes that it is one of the
      technology leaders in cost-effective single wafer processing equipment. In
      the 1970s, IC manufacturers, including many Japanese manufacturers, began
      using multi-wafer (batch) processing equipment in order to increase
      throughput. This technique produced sufficient yields with six-inch wafers
      as a result of the relative ease of handling six-inch wafers in process
      equipment. As more semiconductor manufacturers begin to use eight-inch
      wafers in order to maximize output per wafer pass, the Company believes
      that single wafer processing equipment for critical applications will be
      increasingly used. The Company believes that most new facilities built
      since 1993 have been eight-inch fabs. Of the 125 fabs announced or under
      construction through the year 2000, the Company believes that most are 200
      millimeter (8-inch).
 
    - Temperature Control--GaSonics' products utilize proprietary technology to
      increase yield through accurate temperature control. With precise
      measurement and control of relevant temperatures, chemical reactions are
      optimized to increase throughput and reduce unnecessary damage to the
      wafer. In addition, the Company's systems have the flexibility to
      accommodate the customized thermal processing requirements of its
      customers' advanced ICs. In order to achieve temperature control, the
      Company's systems use either platen-based heating, which is conductive, or
      lamp-based heating, which is radiative, or both.
 
    The Company believes that its proprietary microwave downstream processing
technology can be applied to other cleaning applications, such as selective
isotropic etching. Isotropic etching is a process in which plasma is used to
selectively remove silicon dioxide, silicon nitride and polysilicon from the
wafer to
 
                                       4
<PAGE>
create desired three dimensional contours on the wafer. In order to accommodate
the increased number of mask layers required for the production of advanced ICs,
certain silicon layers on the wafer must be carefully shaped prior to the
deposition of the next layer of material. These etching processes are typically
completed by costly wet chemistry process steps. The Company believes that as
feature sizes decrease, IC manufacturers will replace these wet chemistry
processes or high cost etching steps with more cost-effective downstream dry
chemistry processes. The Company believes that its proprietary downstream
technology will enable manufacturers to utilize dry chemistry processing to
complete these steps with increased yield and lower cost. The Company began
shipping its new high selectivity isotropic etching and cleaning system, the
Strata, in April 1995.
 
HIGH PRESSURE THERMAL PROCESSING
 
    The Company introduced the concept of the application of high pressure to IC
thermal processing with the introduction of its high pressure furnace product.
In IC fabrication, there are a number of thermal process steps that involve the
exposure of the wafer to high temperature over an extended period of time. These
steps include oxidation, which is the growth of insulating materials on the
wafer, and reflow, which is a process that smoothes irregular topographies on a
wafer. By introducing high pressure as a parameter in thermal processing, the
amount of time a wafer must be exposed to high temperatures is reduced. The
length of time an IC may be exposed to high temperatures is sometimes referred
to as the "thermal budget" of the device.
 
    Although high pressure is currently utilized primarily for specialized
applications, the Company believes that its use in the fabrication of advanced
ICs will increase as feature sizes continue to decrease because more advanced
ICs are adversely affected by long exposure to high temperatures. In addition,
the Company believes that high pressure thermal processing provides benefits to
the IC manufacturer including higher yields resulting from increased process
rates and reduced damage to the wafer that can result from long exposure to high
temperatures and increased die per wafer. The Company began shipping VHP systems
in August 1995.
 
PRODUCTS
 
    The Company's major product line consists of advanced dry chemistry
processing equipment for photoresist removal. The Company also offers advanced
dry chemistry processing equipment for post-etch residue removal, isotropic
etching, high pressure furnaces, low-pressure chemical vapor deposition
equipment used for flat panel display manufacturing and products utilizing
plasma chemistry for a variety of non-semiconductor applications. In addition,
the Company provides upgrades, maintenance and spare parts for both current
products and previous generation products.
 
DRY CHEMISTRY PROCESSING SYSTEMS
 
    PHOTORESIST REMOVAL.  The Company's dry chemistry downstream processing
systems are designed to provide advanced IC manufacturers with lower cost of
ownership solutions for photoresist removal. GaSonics currently manufactures
advanced dry chemistry processing systems for photoresist removal, including the
Aura 1000, the Aura 2000-LL, the Aura 3010, the L3510, the PEP3510A and the
PEP3510C. All of these products incorporate the Company's proprietary microwave
downstream processing technology and are designed to be used in the fabrication
of ICs with feature sizes of 0.25 microns and below. The Company's systems have
throughput rates ranging from approximately 45 to 55 wafers per hour, depending
upon wafer size and customer application. A single system typically ranges in
purchase price from approximately $150,000 to $600,000.
 
    The Company introduced its high productivity platform, the PEP, in 1995. The
PEP is a dual chamber platform which, through a proprietary wafer handler and
high yield ashing, provides users with a lower cost per wafer pass while
providing yield advantage with GaSonics' downstream microwave processing.
 
                                       5
<PAGE>
Photoresist removal chambers for the PEP platform were introduced in 1995. The
residue removal chambers were introduced in 1996. In 1994, the Company
introduced its two most recent single chamber product enhancements, the L3510,
an enhancement to the L3500, and the Aura 3010, an enhancement to the Aura 3000,
each of which has extended performance capabilities, including higher
reliability, increased operational flexibility and higher throughput. Sales of
dry chemistry processing equipment for photoresist removal accounted for
approximately 67%, 69% and 62% of the Company's net sales in fiscal 1994, 1995
and 1996, respectively.
 
    ISOTROPIC ETCHING.  Isotropic etching is the removal of materials from a
wafer in both the horizontal and vertical directions at uniform rates. Isotropic
etching allows advanced IC manufacturers to consistently and uniformly remove
materials from a wafer in a more controlled environment, thereby generally
resulting in a lower cost than traditional wet chemistry processing. In fiscal
1995, the Company completed the development of its high selectivity isotropic
etch system, the Strata, for the removal of silicon dioxide, silicon nitride and
polysilicon from the wafer. The Strata features the Company's downstream
microwave technology, and is marketed to prospective customers seeking to
replace costly and toxic wet chemistry processing for certain critical
applications in advanced IC fabrication. The Strata has throughput rates ranging
from 20 to 55 wafers per hour, depending on the wafer size and customer
application. The Company shipped the first Strata in April 1995.
 
HIGH PRESSURE FURNACE SYSTEMS
 
    Over the past 18 years, the Company has marketed a horizontal high pressure
furnace system, the HiPOx, and has sold over 150 of such systems to over 30
semiconductor manufacturers worldwide. In fiscal 1995, the Company completed
development of its vertical high pressure furnace system, the VHP. The VHP
system is intended to provide process simplification by eliminating a mask step
and reducing the time the wafer is exposed to elevated temperatures, thereby
permitting smaller geometries and increasing yields in the manufacture of
advanced ICs. The VHP allows certain customers to extend key elements of their
current fabrication process for up to two generations thereby saving cost and
reducing risk of conversion to different processes. This product is also
designed to meet the industry demand for vertical furnace design for reduced
footprint and small batch sizes of approximately 50 wafers.
 
LOW-PRESSURE CHEMICAL VAPOR DEPOSITION SYSTEMS
 
    In August 1995, the Company acquired Tekisco, one of Japan's leading
manufacturers of low-pressure chemical vapor deposition systems used for flat
panel display manufacturing. Established in 1990, Tekisco began shipments of its
proprietary LPCVD systems for polysilicon-on-glass applications for flat panel
displays in 1991. LPCVD systems have been sold to a number of leading Japanese
flat panel display manufacturers. The Company believes that the acquisition of
Tekisco gives GaSonics an immediate expansion of its market presence in Japan.
The Company now calls this operation its liquid crystal display ("LCD")
division. The Company believes that the equipment needs of flat panel or liquid
crystal manufacturers and semiconductor manufacturers are similar and appear to
be converging as the wafers used in IC manufacturing continue to increase in
size.
 
SPARE PARTS, SERVICE AND SUPPORT
 
    GaSonics also provides a series of products, including spare parts,
retrofits and upgrade kits as well as service, training and support for its
growing installed based. Revenue from such sources accounted for approximately
22%, 20% and 21% of the Company's net sales in fiscal 1994, 1995 and 1996,
respectively. As the Company's systems have become more complex, the Company
believes that its customers will increasingly rely on its expertise for service
and support. In addition, the installed base of the Company's equipment is
expected to increase. As a result, the Company believes that more customers will
purchase its service and support.
 
                                       6
<PAGE>
CUSTOMERS
 
    The Company sells its products to leading IC manufacturers and flat panel
display manufacturers located throughout the United States, Europe and the
Asia/Pacific. Sales to Intel and Motorola accounted for approximately 26% and
10%, respectively, of net sales in fiscal 1994. Sales to Intel accounted for
approximately 20% of net sales in fiscal 1995 and 11% of net sales in fiscal
1996. The Company expects that sales of its products to relatively few
customers, particularly Intel, Motorola, Samsung, Siemens and Lucent
Technologies will continue to account for a high percentage of its net sales in
the foreseeable future. None of the Company's customers has entered into a
long-term agreement requiring it to purchase the Company's products. Moreover,
sales to certain of the Company's customers have decreased as those customers
have completed or delayed purchasing requirements for new or expanded
fabrication facilities. Although the composition of the group comprising the
Company's largest customers has varied from year to year, the loss of a
significant customer or any reduction in orders by any significant customer,
including reductions due to customer departures from traditional buying
patterns, market, economic or competitive conditions in the semiconductor
industry or in the industries that manufacture products utilizing integrated
circuits, could materially adversely affect the Company's business, financial
condition and results of operations.
 
SALES, SERVICE AND CUSTOMER SUPPORT
 
    The Company believes its sales, service and customer support organizations
are critical to its long term customer relationships and provide the Company
with a competitive advantage in the process equipment market. These
relationships are particularly important in the semiconductor capital equipment
market, as the Company believes that once a semiconductor manufacturer has
selected a particular supplier's capital equipment, that manufacturer generally
relies upon that equipment for the specific product line application and
frequently will attempt to consolidate its other capital equipment requirements
with the same supplier. The Company's sales and service representatives maintain
close working relationships with customers in order to identify their current
and future semiconductor equipment requirements and to assist customers with the
design of their new or upgraded fabrication facilities. In addition, these
working relationships assist the Company in designing its products to meet the
stringent qualification requirements of many of its key customers. As a result
of these close relationships, the Company believes it is positioned to develop
and market products which meet the current and future requirements of its key
customers and other advanced IC manufacturers.
 
    The Company markets and sells its products in the United States and overseas
through its marketing and direct sales organization including application and
process development engineers and logistics personnel. The Company also sells
its products overseas through 6 representatives in Europe and Asia/ Pacific. In
1994, the Company established a relationship with one of the leading
distributors of semiconductor capital equipment in Japan for sales of its
photoresist removal equipment and has staffed its own subsidiary in Japan to
market and sell its high pressure systems. The Company currently has eight
United States sales offices located in Austin, Texas; Dallas, Texas; Fort
Washington, Pennsylvania; Rockaway, New Jersey; Aloha, Oregon; Mesa, Arizona;
Hopewell, New York; and its corporate headquarters in San Jose, California. At
each of its sales offices, the Company provides support personnel and
application engineers in order to ensure dedicated technical and field process
support throughout the United States.
 
    The Company's field service and technical support personnel are based
throughout the United States, Europe and Asia/Pacific, and directly support
domestic and international warranty service, post-warranty contract service,
equipment installations and training. Field service support in some countries
overseas is provided through third party representatives. The Company's field
service engineers are located in 23 sites throughout the United States, Europe
and Asia/Pacific, including dedicated site-specific engineers contracted by
certain customers, such as Intel, Motorola, Lucent Technologies and Texas
Instruments.
 
                                       7
<PAGE>
    The Company's customer support and service organizations link the customers
with the Company's overall quality and support efforts. The Company is preparing
to be in compliance with ISO-9001, which requires a strict system of standards
used primarily in Europe to measure the Company's ability to achieve certain
quality milestones.
 
    The Company generally offers standard warranty terms for two years on parts
and labor on equipment sales. The Company also offers service contracts to its
customers for continued maintenance of the systems that are not covered by
warranty.
 
    The Company has and is continuing to increase its sales, field service and
customer support presence in the Asia/Pacific. Since the end of fiscal 1993, the
Company has established subsidiaries in the U.K., France, Korea and Japan, and
branches in Italy, Singapore and Taiwan. The Company has staffed these
subsidiaries and branches with sales, field service, technical support and
application engineers to support further penetration in the region. The Company
intends to continue investing significant resources in order to further
penetrate the Asia/Pacific market. The Company's goal is to develop
knowledgeable local sales, service and customer support resources throughout the
region in order to increase communication between the Company and Asia/Pacific
IC manufacturers and to reduce response times for sales and support inquiries.
 
    In August 1995, the Company acquired Tekisco, Ltd. from Kishimoto Sangyo Co.
Ltd. of Tokyo, Japan. Tekisco is a manufacturer of LPCVD equipment used for the
manufacture of flat panel displays. FPDs are market driven by portable computing
and telecommunications devices. FPD or liquid crystal display manufacturing
utilizes very similar processes to IC processing. Approximately 90% of the
advanced FPDs produced worldwide are manufactured in Japan. The acquisition of
Tekisco is intended to enable GaSonics to continue to penetrate this market and
to further establish the credibility of GaSonics as a supplier in Japan.
 
BACKLOG
 
    The Company schedules production of its systems based upon backlog, informal
customer commitments and general economic forecasts for its targeted markets.
The Company includes in its backlog only those customer orders for systems for
which it has accepted purchase order numbers and assigned shipment dates within
twelve months as well as orders for spare parts and service and support of
systems. The Company's backlog for its systems, spare parts and service and
support was approximately $54.8 and $32.4 million at the end of fiscal years
1995 and 1996, respectively. Historically, the Company's backlog has fluctuated
significantly primarily as a result of the cyclical nature of construction and
equipping of new IC fabrication facilities. The equipment requirements of new
fabrication facilities cannot be determined with accuracy, and therefore the
Company's backlog at any certain date is not indicative of future growth. In
addition, because of orders received in the same quarter in which a system is
shipped, possible changes in system delivery schedules, cancellations and the
rescheduling of system orders, orders being subject to cancellation, deferral or
rescheduling by the customer with limited or no penalties, and potential delays
in system shipments, the Company's backlog at any particular date is not
necessarily representative of actual sales for any succeeding period.
 
MANUFACTURING
 
    The Company's manufacturing strategy is to produce high quality,
cost-effective systems and assemblies. In order to lower production costs, the
Company performs manufacturing activities that add value or that require unique
technology or specialized knowledge and utilizes subcontractors to perform other
manufacturing activities. The Company is relying increasingly on subcontractors
to fabricate and assemble components and perform other activities.
 
                                       8
<PAGE>
    The Company's principal manufacturing activities include assembly and test
work and are conducted at the Company's facility in San Jose, California and in
Atsugi City, Japan for the LPCVD business. Assembly includes inspection,
subassembly and final assembly and test includes module test and final systems
test. The Company's Class 10, Class 100 and Class 1000 clean rooms enable the
Company to test its products to its customers' acceptance criteria prior to
shipment. In 1994, the Company underwent a "Supplier Quality Assessment" from
SEMATECH, a consortium of U.S. semiconductor manufacturers, which is a key
milestone for ISO-9001 certification. As part of an overall expansion program,
the Company leased additional facilities dedicated to thermal products and the
newly established customer satisfaction center and reconfigured other facilities
to accommodate the increase in personnel and provide cleaner manufacturing
environments as well as additional research and development activity.
 
    The Company is subject to a variety of governmental regulations relating to
the use, storage, discharge, handling, emission, generation, manufacture and
disposal of toxic or other hazardous substances used to manufacture the
Company's products. The Company believes that it is currently in compliance in
all material respects with such regulations and that it has obtained all
necessary environmental permits to conduct its business. Nevertheless, the
failure to comply with current or future regulations could result in substantial
fines being imposed on the Company, suspension of production, alteration of its
manufacturing process or cessation of operations. Such regulations could require
the Company to acquire expensive remediation equipment or to incur substantial
expenses to comply with environmental regulations. Any failure by the Company to
control the use, disposal or storage of, or adequately restrict the discharge
of, hazardous or toxic substances could subject the Company to significant
liabilities.
 
RESEARCH AND DEVELOPMENT
 
    The markets for semiconductor manufacturing equipment, including the markets
that utilize the Company's equipment, are characterized by rapid technological
development and product innovation. The Company intends to continue to commit
substantial resources to research and development in both dry chemistry
processing, high pressure thermal processing and LPCVD for the flat panel
display market.
 
    In order to maintain its long-term relationships with existing customers,
the Company commits substantial resources to the continuous improvement of
existing products and developing new products and technology. Customers with
large installed bases increasingly require their suppliers to improve existing
products in order to avoid the long qualifying evaluations required with new
equipment, which can be costly and risky. The Company's research and development
for product improvement includes in-house validation tests of major hardware
changes as well as detailed process characterization in the Company's clean
rooms.
 
    Historically, the Company has devoted a significant portion of its financial
resources to research and development programs and expects to continue to
allocate significant resources to these efforts. For fiscal 1994, 1995 and 1996,
total research and development expenditures were approximately $6.0 million,
$12.3 million and $18.0 million, respectively, and represented 9.0%, 12.1% and
14.2% of the Company's net sales, respectively.
 
COMPETITION
 
    The semiconductor capital equipment industry is intensely competitive. A
substantial investment is required by customers to install and integrate capital
equipment into a semiconductor production line. As a result, once a
semiconductor manufacturer has selected a particular supplier's capital
equipment, the Company believes that the manufacturer generally relies upon that
equipment for the specific production line application and frequently will
attempt to consolidate its other capital equipment requirements with the same
supplier. Accordingly, the Company expects to experience difficulty in selling
to a particular customer for a significant period of time if that customer
selects a competitor's capital equipment. The Company currently has only one
principal product line and experiences intense competition worldwide
 
                                       9
<PAGE>
from a number of leading foreign and domestic manufacturers, including
Alcantech, Applied Materials, Inc., Fusion Systems Corporation, Lam Research
Corporation, Matrix Semiconductor Systems, Inc., Mattson Technology, Inc.,
Plasma Systems and Ramco, some of which have substantially greater installed
bases and greater financial, marketing, technical and other resources than the
Company. Certain of the Company's competitors have announced the introduction
of, or have introduced, competitive products that offer other technologies and
improvements. Applied Materials and Lam Research have introduced modules to
their products which remove photoresist using dry chemistry processing and
thereby compete with the Company's products. The Company expects its competitors
to continue to develop enhancements to and future generations of competitive
products that may offer improved price or performance features. New product
introductions and enhancements by the Company's competitors could cause a
significant decline in sales or loss of market acceptance of the Company's
systems in addition to intense price competition or otherwise make the Company's
systems or technology obsolete or noncompetitive. The Company believes that it
will continue to face competition from current and new suppliers employing other
technologies, such as wet chemistry, traditional dry chemistry and other
techniques, as such competitors attempt to extend the capabilities of their
existing products. Increased competitive pressure could lead to reduced demand
and lower prices for the Company's products, thereby materially adversely
affecting the Company's operating results.
 
    The principal elements of competition in dry chemistry processing for
photoresist removal and etching are technological innovation, total cost of
ownership of the systems, including yield, price, product performance and
throughput capability, quality, and reliability, and customer service and
support. Although the Company believes that it competes favorably with respect
to each of these factors, new product introductions by the Company's competitors
could cause a decline in sales or loss of market acceptance of the Company's
existing products. In addition, by virtue of its reliance on sales of advanced
dry chemistry processing equipment, the Company could be at a disadvantage
compared to certain competitors that offer more diversified product lines.
 
    The Company believes that to remain competitive it will have to commit
significant financial resources to develop new product features and
enhancements, to introduce next generation photoresist removal products on a
timely basis, and to maintain customer service and support centers worldwide. In
marketing its products, the Company will face competition from suppliers
employing new technologies in order to extend the capabilities of competitive
products beyond their current limits or increase their productivity. In
addition, increased competitive pressure could lead to intensified price-based
competition, resulting in lower prices and margins, which would materially
adversely affect the Company's business, financial condition and operating
results.
 
    In addition, Japanese IC process equipment manufacturers have a dominant
share of the market for certain types of integrated circuits for which the
Company's systems are used. Japanese manufacturers are well established in the
Japanese process equipment market, and it is difficult for non-Japanese
manufacturers to penetrate the Japanese market. Furthermore, Japanese
semiconductor manufacturers have extended their influence outside of Japan by
licensing products and process technologies to non-Japanese semiconductor
manufacturers. Such licenses could result in a recommendation to use certain
semiconductor capital equipment manufactured by Japanese companies. The Company
has not established itself as a major competitor in the Japanese market and
there can be no assurance that the Company will be able to achieve significant
sales to Japanese IC manufacturers. There can be no assurance that the Company
will be able to compete successfully in the future.
 
    Tekisco's competitors in the LPCVD market include Japan-based companies and
Japan-based joint ventures such as Applied Komatsu and Koyo Lindbergh. These
competitors manufacture alternative technology systems and they could, at any
time, enter the Company's markets with improved technology or with systems that
are directly competitive with those of Tekisco.
 
                                       10
<PAGE>
INTELLECTUAL PROPERTY RIGHTS
 
    The Company owns 15 United States patents which expire between 1998 and 2012
and has 5 U.S. patents pending. In addition, the Company has 15 foreign patents
which expire between 1998 and 2011 and has applied for 2 additional foreign
patents. Certain of these patents were acquired by the Company from Branson
International Plasma Corporation (IPC). One additional U.S. patent application
has been assigned to the Company in connection with the acquisition of Tekisco.
The Company has a policy of seeking patents when appropriate on inventions
resulting from its ongoing research and development and manufacturing
activities. The Company also has seven trademarks. Nevertheless, the Company
believes that its success will depend more upon the innovation, technological
expertise and marketing abilities of its employees than upon the protection
provided by patents, trademarks, copyrights and other intellectual property
rights.
 
    Although the Company attempts to protect its intellectual property rights
through patents, copyrights, trade secrets and other measures, there can be no
assurance that the Company will be able to protect its technology adequately or
that competitors will not be able to develop similar technology independently.
There can be no assurance that any of the Company's pending patent applications
will be issued or that foreign intellectual property laws will protect the
Company's intellectual property rights. There can be no assurance that any
patent issued to the Company will not be challenged, invalidated or circumvented
or that the rights granted thereunder will provide competitive advantages to the
Company. Furthermore, there can be no assurance that others will not
independently develop similar products, duplicate the Company's products or, if
patents are issued to the Company, design around the patents issued to the
Company.
 
    As is typical in the semiconductor industry, the Company has received
notices from time to time from third parties alleging infringement claims.
Although there currently are no pending claims or lawsuits against the Company
regarding any possible infringement claims, there can be no assurance that
infringement claims by third parties or claims for indemnification resulting
from infringement claims in the future will not be asserted or that such
assertions, if proven to be true, will not materially adversely affect the
Company's business, financial condition and results of operations. If any such
claims are asserted against the Company, the Company may seek to obtain a
license under the third party's intellectual property rights. There can be no
assurance that a license will be available on reasonable terms or at all. The
Company could decide, in the alternative, to resort to litigation to challenge
such claims or enforce its proprietary rights. Such challenges could be
extremely expensive and time consuming and could materially adversely affect the
Company's business, financial condition and results of operations.
 
EMPLOYEES
 
    At September 30, 1996, the Company had approximately 480 full-time
employees. The Company believes its future success will depend in large part on
its ability to attract and retain highly skilled and motivated employees. None
of the employees of the Company is covered by a collective bargaining agreement.
The Company considers its relationships with its employees to be good.
 
                                       11
<PAGE>
ADDITIONAL RISK FACTORS
 
SIGNIFICANT FLUCTUATIONS IN OPERATING RESULTS
 
    The Company's operating results have fluctuated significantly in the past
and will fluctuate significantly in the future. The Company anticipates that
factors continuing to affect its future operating results will include the
cyclicality of the semiconductor industry and the markets served by the
Company's customers, the timing of significant orders, patterns of capital
spending by customers, the proportion of direct sales and sales through
distributors, the proportion of international sales to net sales, changes in
pricing by the Company, its competitors, customers or suppliers, market
acceptance of new and enhanced versions of the Company's products, the mix of
products sold, financial systems, procedures and controls, discounts, the timing
of new product announcements and releases by the Company or its competitors,
delays, cancellations or rescheduling of orders due to customer financial
difficulties or otherwise, the Company's ability to produce systems in volume
and meet customer requirements, changes in overhead absorption levels due to
changes in the number of systems manufactured, political and economic
instability and lengthy sales cycles. Gross margins have varied and will vary
materially based on a variety of factors including the mix and average selling
prices of systems sales, the mix of revenues, including service and support
revenues, and the costs associated with new product introductions and
enhancements and the customization of systems. Furthermore, announcements by the
Company or its competitors of new products and technologies could cause
customers to defer purchases of the Company's existing systems, which would also
materially adversely affect the Company's business, financial condition and
results of operations. The Company has expended significant resources with
respect to the development and ramp up of production and anticipated commercial
shipments of four recently introduced products, the Strata, a high selectivity
etch system, the VHP, a vertical high pressure furnace system, the PEP, a
performance enhancement platform, and the 2106 LPCVD, a low pressure chemical
vapor deposition system. Gross margins in fiscal 1996 decreased from the level
attained during fiscal 1995, in part, to start-up inefficiencies associated with
these introductions and sales, competitive pricing pressures, changes in product
mix, including the products sold by the Company's LCD division in Japan, and
other factors. Additionally, sales and earnings for the last half of fiscal 1996
were materially adversely impacted by the current semiconductor business
slowdown and, while the Company has and is continuing to manage its expenses to
partially offset the loss of income from the decline in revenue, it is
anticipated that this slowdown in the industry will continue into next fiscal
year and will continue to have a material adverse affect on the Company's future
revenues and operating results. See "Expansion of Operations; Management of
Growth" and "Management's Discussion and Analysis of Financial Condition and
Results of Operations."
 
LIMITED SYSTEM SALES; BACKLOG
 
    The Company derives a substantial portion of its sales from the sale of a
relatively small number of systems which typically range in purchase price from
approximately $150,000 to $600,000 for its photoresist removal systems and up to
approximately $2.0 million for its other products. As a result, the timing of
recognition of revenue for a single transaction could have a material adverse
effect on the Company's sales and operating results. The Company's backlog at
the beginning of a quarter typically does not include all sales required to
achieve the Company's sales objectives for that quarter. Moreover, all customer
purchase orders are subject to cancellation or rescheduling by the customer with
limited or no penalties and, therefore, backlog at any particular date is not
necessarily representative of actual sales for any succeeding period. The
Company's net sales and operating results for a quarter may depend upon the
Company obtaining orders for systems to be shipped in the same quarter that the
order is received. The Company's business and financial results for a particular
period could be materially adversely affected if an anticipated order for even
one system is not received in time to permit shipment during such period.
Furthermore, most of the Company's quarterly net sales have recently been
realized near the end of the quarter. A delay in a shipment near the end of a
particular quarter, due, for example, to an unanticipated shipment
 
                                       12
<PAGE>
rescheduling, to cancellations or deferrals by customers, to unexpected
manufacturing difficulties experienced by the Company or to supply shortages,
may cause net sales in a particular quarter to fall significantly below the
Company's expectations and may materially adversely affect the Company's
operating results for such quarter. In addition, significant investments in
research and development, capital equipment and customer service and support
capability worldwide have resulted in significant fixed costs which the Company
will not be able to reduce rapidly if sales goals for a particular period are
not met, which has recently been the case. Because the Company builds its
systems according to forecast, a reduction in customer orders or backlog could
present further difficulties regarding the Company's ability to plan production
and inventory levels, which could adversely impact operating results. The impact
of these and other factors on the Company's operating results in any future
period cannot be forecasted accurately. See "Management's Discussion and
Analysis of Financial Condition and Results of Operations."
 
CYCLICALITY OF SEMICONDUCTOR INDUSTRY
 
    The Company's business depends in significant part upon capital expenditures
by manufacturers of semiconductor devices, including manufacturers that are
opening new or expanding existing fabrication facilities, which, in turn, depend
upon the current and anticipated market demand for such devices and products
utilizing such devices. The semiconductor industry is highly cyclical and
historically has experienced periods of oversupply, resulting in significantly
reduced demand for capital equipment, including systems manufactured and
marketed by the Company. The semiconductor industry has experienced significant
growth in recent years which has resulted in significant growth in the capital
equipment industry. However, in recent months the semiconductor industry has
experienced a cyclical downturn, as evidenced by recent results of the
industry's book-to-bill ratio as published by the Semiconductor Industry
Association. More recently, the semiconductor equipment industry's book-to-bill
ratio, as published by the Semiconductor Equipment Industry Association, has
shown a dramatic decline in new equipment orders for the entire equipment
industry relative to current sales levels, indicating a pronounced cyclical
downturn. Additional evidence of an existing industry downturn is exhibited by
recent announcements by several semiconductor manufacturers of delays or
cancellations of previously planned capacity additions. The Company has recently
experienced significant delays of new orders and rescheduling of existing orders
that have materially adversely affected the Company's fiscal 1996 financial
results and is expected to materially adversely affect future financial results.
Accordingly, the Company can give no assurance that it will be able to achieve
or maintain its current level of sales. Additionally, the Company anticipates
that a significant portion of new orders depend upon demand from integrated
circuit ("IC") manufacturers building or expanding large fabrication facilities,
and there can be no assurance that such demand will exist. See
"Business--Industry Background."
 
HIGHLY COMPETITIVE INDUSTRY
 
    The semiconductor capital equipment industry is intensely competitive. A
substantial investment is required by customers to install and integrate capital
equipment into a semiconductor production line. As a result, once a
semiconductor manufacturer has selected a particular vendor's capital equipment,
the Company believes that the manufacturer generally relies upon that equipment
for the specific production line application and frequently will attempt to
consolidate its other capital equipment requirements with the same vendor.
Accordingly, the Company expects to experience difficulty in selling to a
particular customer for a significant period of time if that customer selects a
competitor's capital equipment. The Company currently has only one principal
product line and experiences intense competition worldwide from a number of
foreign and domestic manufacturers, including Alcantech, Applied Materials,
Inc., Fusion Systems Corporation, Lam Research Corporation, Matrix Semiconductor
Systems, Inc., Mattson Technology, Inc., Plasma Systems and Ramco, many of which
have substantially greater installed bases and greater financial, marketing,
technical and other resources than the Company. Certain of the Company's
competitors have recently announced the introduction of, or have introduced,
competitive products that
 
                                       13
<PAGE>
offer other technologies and improvements. Applied Materials and Lam Research
have introduced and sells modules to their products which remove photoresist
using dry chemical processing and, therefore, compete with the Company's
products. The Company expects its competitors to continue to develop
enhancements to and future generations of competitive products that may offer
improved price or performance features. New product introductions and
enhancements by the Company's competitors could cause a significant decline in
sales or loss of market acceptance of the Company's systems in addition to
intense price competition or otherwise make the Company's systems or technology
obsolete or noncompetitive In addition, by virtue of its reliance on sales of
advanced dry chemistry processing equipment, the Company could be at a
disadvantage compared to certain competitors that offer more diversified product
lines. The Company believes that it will continue to face competition from
current and new vendors employing other technologies, such as wet chemistry,
traditional dry chemistry and other ashing techniques, as such competitors
attempt to extend the capabilities of their existing products. Increased
competitive pressure has led to reduced demand and lower prices for the
Company's products, thereby materially adversely affecting the Company's
operating results. There can be no assurance that the Company will be able to
compete successfully in the future. See "Business--Competition."
 
    Competitors of the Company's LCD division in Japan include Japan-based
companies and Japan-based joint ventures such as Applied Komatsu and Koyo
Lindbergh. These competitors manufacture alternative technology systems and they
could, at any time, enter the Company's markets with improved technology or with
systems that are directly competitive with those of the Company's LCD division.
 
DEPENDENCE ON KEY CUSTOMERS
 
    Historically, the Company has sold a significant proportion of its systems
in any particular period to a limited number of customers. Sales to the
Company's ten largest customers in fiscal 1994, 1995 and 1996 accounted for
approximately 71%, 68% and 51% of net sales, respectively. The Company expects
that sales of its products to relatively few customers, particularly Intel,
Motorola, Samsung, Siemens and Lucent Technologies will continue to account for
a high percentage of net sales in the foreseeable future. None of the Company's
customers has entered into a long-term agreement requiring it to purchase the
Company's products. Moreover, sales to certain of its customers have decreased
as those customers have completed or delayed purchasing requirements for new or
expanded fabrication facilities. Although the composition of the group
comprising the Company's largest customers has varied from year to year, the
loss of a significant customer or any reduction in orders from any significant
customer, including reductions from recent buying patterns, market, economic or
competitive conditions in the semiconductor industry or in the industries that
manufacture products utilizing ICs, could materially adversely affect the
Company's business, financial condition and results of operations. The Company's
ability to increase or maintain current sales levels in the future will depend
in part upon its ability to obtain orders from new customers as well as the
financial condition and success of its customers and the general economy, of
which there can be no assurance. See "Business--Customers."
 
EXPANSION OF OPERATIONS; MANAGEMENT OF GROWTH
 
    The Company has undergone a period of rapid growth. Since 1993, the Company
has significantly increased the scale of its operations to support increased
sales levels and has expanded its operations to address critical infrastructure
requirements, including the hiring of additional personnel, commencement of
independent operations in the United Kingdom, France, Italy, Korea, Japan,
Singapore and Taiwan and significant investments in research and development to
support product development. The Company's expansion has resulted in
significantly higher operating expenses and due to the recent slowdown in new
orders, it is anticipated that the Company's future operating results will be
materially adversely affected.
 
    The growth in the Company's sales and expansion in the scope of its
operations has placed a considerable strain on its management, financial and
other resources and has required the Company to initiate an extensive
reevaluation of its operating and financial systems, procedures and controls.
Although
 
                                       14
<PAGE>
the Company is currently implementing new management information, manufacturing
and cost accounting systems, these systems are not currently expected to be
fully operational until the second quarter of fiscal 1997 at the earliest. There
can be no assurance that any existing or new systems, procedures or controls
will be adequate to support the Company's operations or that its new systems
will be implemented in a cost-effective and timely manner.
 
RAPID TECHNOLOGICAL CHANGE; IMPORTANCE OF TIMELY PRODUCT INTRODUCTION
 
    The semiconductor manufacturing industry is subject to rapid technological
change and new product introductions and enhancements. The Company's ability to
be competitive will depend in part upon its ability to develop new and enhanced
systems and to introduce these systems at competitive prices and in a timely and
cost effective manner to enable customers to integrate the systems into their
operations either prior to or upon commencement of volume product manufacturing.
In addition, new product introductions or enhancements by the Company's
competitors could cause a decline in sales or loss of market acceptance of the
Company's existing products. Increased competitive pressure has led to
intensified price-based competition resulting in lower prices and margins, which
has and could continue to materially adversely affect the Company's business,
financial condition and results of operations. Any success of the Company in
developing, introducing and selling new and enhanced systems depends upon a
variety of factors including product selection, timely and efficient completion
of product design and development, timely and efficient implementation of
manufacturing and assembly processes, effective sales and marketing and product
performance in the field. In particular, the Company's future performance will
depend in part upon the successful commercialization of the Strata, the VHP and
the PEP. There can be no assurance that any such product will achieve any
significant revenues or contribute to the profitability of the Company. Because
new product development commitments must be made well in advance of sales, new
product decisions must anticipate both the future demand for the type of ICs
under development by leading IC manufacturers and the equipment required to
produce such ICs. There can be no assurance that the Company will be successful
in selecting, developing, manufacturing and marketing new products or in
enhancing existing products.
 
    Because of the large number of components in, and the complexity of, the
Company's systems, significant delays can occur between a system's initial
introduction and the commencement of volume production. As is typical in the
semiconductor capital equipment market, the Company has experienced delays from
time to time in the introduction of, and certain technical and manufacturing
difficulties with, certain of its systems and enhancements and may experience
delays and technical and manufacturing difficulties in future introductions or
volume production of new systems or enhancements. The Company's inability to
complete the development or meet the technical specifications of any of its new
systems or enhancements or to manufacture and ship these systems or enhancements
in volume and in a timely manner would materially adversely affect the Company's
business, financial condition and results of operations as well as its customer
relationships. In addition, the Company may incur substantial unanticipated
costs to ensure the functionality and reliability of its future product
introductions early in the product's life cycle. If new products have
reliability or quality problems, reduced orders or higher manufacturing costs,
delays in collecting accounts receivable and additional service and warranty
expenses may result, which events could materially adversely affect the
Company's business, financial condition and results of operations. See
"Business--Research and Development."
 
LENGTHY SALES CYCLE
 
    Sales of the Company's systems depend, in significant part, upon the
decision of a prospective customer to increase manufacturing capacity through
the expansion of existing fabrication facilities or the opening of new
facilities, which typically involves a significant capital commitment. The
Company often experiences delays in finalizing system sales following initial
system qualification while the customer evaluates and receives approvals for the
purchase of the Company's systems and completes a new or
 
                                       15
<PAGE>
expanded facility. Due to these and other factors, the Company's systems
typically have a lengthy sales cycle during which the Company may expend
substantial funds and management effort. The Company believes that the length of
the sales cycle will continue to increase as certain of its customers centralize
purchasing decisions into one decision making entity, which is expected to
intensify the evaluation process and require additional sales and marketing
expenditures by the Company.
 
RISKS ASSOCIATED WITH THE JAPANESE MARKET
 
    The Company believes that increased penetration of the Asia Pacific market,
particularly Japan, will be essential to its future financial performance. The
Company has sold a relatively few number of systems to Japanese semiconductor
manufacturers, although there was a significant increase in the Company's sales
from Japan in fiscal 1996 compared to fiscal 1995. To date, the Company has not
fully developed a customer service and support capability in Japan and remains
at a disadvantage in selling, servicing and supporting products in Japan. The
Japanese semiconductor market (including fabrication plants operated outside of
Japan by Japanese semiconductor manufacturers) represents a substantial
percentage of the worldwide semiconductor manufacturing capacity, and has been
difficult for non-Japanese companies to penetrate. Furthermore, the licensing of
products and process technologies by Japanese semiconductor manufacturers to
non-Japanese semiconductor manufacturers could result in a recommendation to use
certain semiconductor capital equipment manufactured by Japanese companies. Late
in fiscal 1995, the Company acquired a local company in Japan which
manufactures, markets and sells LPCVD equipment for the FPD market, but there
can be no assurance that this company will enable the Company to penetrate the
photoresist removal market in Japan. In addressing this market, the Company is
at a distinct competitive disadvantage compared to leading Japanese suppliers,
many of which have long-standing collaborative relationships with Japanese
semiconductor manufacturers. In addition, since 1992, Japanese semiconductor
manufacturers have substantially reduced their levels of capital spending on new
fabrication facilities and equipment, thereby increasing competitive pressures
in the Japanese market. Although the Company is investing significant resources
in Japan which has significantly increased operating expenses, there can be no
assurance that the Company will be able to achieve significant sales to the
Japanese semiconductor market. See "Business--Sales, Service and Customer
Support."
 
INTERNATIONAL SALES
 
    International sales accounted for 41%, 40% and 54% of net sales in fiscal
years 1994, 1995 and 1996, respectively. The Company has established independent
operations in the United Kingdom, France, Italy, Korea, Japan, Singapore and
Taiwan and acquired a company in Japan. The Company anticipates that
international sales will continue to account for a significant portion of net
sales. International sales are subject to certain risks, including unexpected
changes in regulatory requirements, difficulty in satisfying existing regulatory
requirements, exchange rates, foreign currency fluctuations, tariffs and other
barriers, political and economic instability, potentially adverse tax
consequences, natural disasters, outbreaks of hostilities, difficulties in
accounts receivable collection, extended payment terms, difficulties in managing
distributors or representatives and difficulties in staffing and managing
foreign subsidiary and branch operations. The Company is also subject to the
risks associated with the imposition of legislation and import and export
regulations. The Company cannot predict whether tariffs, quotas, duties, taxes
or other charges or restrictions will be implemented by the United States, Japan
or any other country upon the importation or exportation of the Company's
products in the future. There can be no assurance that these factors will not
have a material adverse effect on the Company's business, financial condition
and results of operations. See "Business--Sales, Service and Customer Support."
 
INTELLECTUAL PROPERTY RIGHTS
 
    Although the Company attempts to protect its intellectual property rights
through patents, copyrights, trade secrets and other measures, it believes that
its financial performance will depend more upon the
 
                                       16
<PAGE>
innovation, technological expertise and marketing abilities of its employees
than upon such protection. There can be no assurance that any of the Company's
pending patent applications will be issued or that foreign intellectual property
laws will protect the Company's intellectual property rights. There can be no
assurance that any patent issued to the Company will not be challenged,
invalidated or circumvented or that the rights granted thereunder will provide
competitive advantages to the Company. Furthermore, there can be no assurance
that others will not independently develop similar products, duplicate the
Company's products or, if patents are issued to the Company, design around the
patents issued to the Company.
 
    As is typical in the semiconductor industry, the Company has received
notices from time to time from third parties alleging infringement claims.
Although there are currently no pending claims or lawsuits against the Company
regarding any possible infringement claims, there can be no assurance that
infringement claims by third parties or claims for indemnification resulting
from infringement claims will not be asserted in the future or that such
assertions, if proven to have merit, will not materially adversely affect the
Company's business, financial condition and results of operations. If any such
claims are asserted against the Company, the Company may seek to obtain a
license under the third party's intellectual property rights. There can be no
assurance that a license will be available on reasonable terms or at all. The
Company could decide, in the alternative, to resort to litigation to challenge
such claims. Such challenges could be extremely expensive and time consuming and
could materially adversely affect the Company's business, financial condition
and results of operations. See "Business--Intellectual Property Rights."
 
SOLE OR LIMITED SOURCES OF SUPPLY; RELIANCE ON SUBCONTRACTORS; COMPLEXITY IN
  MANUFACTURING PROCESS
 
    Certain components, subassemblies and services necessary for the manufacture
of the Company's systems are obtained from a sole supplier or a limited group of
suppliers. Specifically, the Company relies on three companies for supply of the
robotics used in its products and two other companies for microwave power
supplies used in all of its ashing systems. The Company does not maintain any
long-term supply agreements with any of its suppliers. The Company is relying
increasingly on outside vendors to manufacture certain components and
subassemblies. The Company's reliance on sole or a limited group of suppliers
and the Company's increasing reliance on subcontractors involve several risks,
including a potential inability to obtain an adequate supply of required
components and reduced control over pricing and timely delivery of components
and subassemblies. Because the manufacture of certain of these components and
subassemblies is an extremely complex process and requires long lead times,
there can be no assurance that delays or shortages caused by suppliers will not
occur in the future. Certain of the Company's suppliers have relatively limited
financial and other resources. Any inability to obtain adequate deliveries or
any other circumstance that would require the Company to seek alternative
sources of supply or to manufacture such components internally could delay the
Company's ability to ship its products, which could damage relationships with
current and prospective customers and could have a material adverse effect on
the Company's business, financial condition and results of operations. The
Company's LCD division in Japan is heavily dependent on one key supplier for
quartz and ceramic fabrication and is seeking alternative sources. See
"Management's Discussion and Analysis of Financial Condition and Results of
Operations" and "Business--Manufacturing."
 
FUTURE ACQUISITIONS
 
    In August 1995, the Company acquired its flat panel display equipment (LCD)
division in Japan (formerly called Tekisco). In the future, the Company may
pursue acquisitions of additional product lines, technologies or businesses.
Future acquisitions by the Company may result in potentially dilutive issuances
of equity securities, incurrence of debt and amortization expenses related to
goodwill and other intangible assets, which could materially adversely affect
the Company's financial condition and results of operations. In addition,
acquisitions involve numerous risks, including difficulties in the assimilation
of the operations,
 
                                       17
<PAGE>
technologies and products of the acquired companies, the diversion of
management's attention from other business concerns, risks of entering markets
in which the Company has no or limited direct prior experience, and the
potential loss of key employees of the acquired company. From time to time, the
Company has engaged in preliminary discussions with third parties concerning
potential acquisitions of product lines, technologies and businesses; however,
there are currently no negotiations, commitments or agreements with respect to
any acquisition. In the event that such an acquisition does occur, there can be
no assurance as to the effect thereof on the Company's business, financial
condition or operating results.
 
DEPENDENCE ON KEY PERSONNEL
 
    The Company's financial performance will depend in significant part upon the
continued contributions of its officers and key personnel, many of whom would be
difficult to replace. No employee has an employment or noncompetition agreement
with the Company. The loss of any key person could have a material adverse
effect on the business, financial condition and results of operations of the
Company. During the last twelve months, a number of senior management personnel
have left the Company to pursue other opportunities. Although the Company has
replaced most of these senior management personnel, there can be no assurance
that these individuals will successfully integrate into the Company's senior
management team. In addition, the Company's future operating results depend in
part upon its ability to attract and retain other qualified management,
engineering, financial and accounting, technical, marketing and sales and
support personnel for its operations. Competition for such personnel is intense,
and there can be no assurance that the Company will be successful in attracting
or retaining such personnel. The failure to attract or retain such persons could
materially adversely affect the Company's business, financial condition and
results of operations. See "Business--Employees" and "Executive Officers of the
Registrant."
 
ENVIRONMENTAL REGULATIONS
 
    The Company is subject to a variety of governmental regulations relating to
the use, storage, discharge, handling, emission, generation, manufacture and
disposal of toxic or other hazardous substances used to manufacture the
Company's products. The Company believes that it is currently in compliance in
all material respects with such regulations and that it has obtained all
necessary environmental permits to
conduct its business. Nevertheless, the failure to comply with current or future
regulations could result in substantial fines being imposed on the Company,
suspension of production, alteration of its manufacturing process or cessation
of operations. Such regulations could require the Company to acquire expensive
remediation equipment or to incur substantial expenses to comply with
environmental regulations. Any failure by the Company to control the use,
disposal or storage of, or adequately restrict the discharge of, hazardous or
toxic substances could subject the Company to significant liabilities. See
"Business-- Manufacturing."
 
EFFECT OF CERTAIN ANTI-TAKEOVER PROVISIONS
 
    As of November 15, 1996, the Company's officers, directors and members of
their families that may be deemed affiliates of such persons beneficially owned
approximately 27.9% of the Company's outstanding shares of Common Stock.
Accordingly, these stockholders will be able to significantly influence the
election of the Company's directors and the outcome of corporate actions
requiring stockholder approval, such as mergers and acquisitions, regardless of
how other stockholders of the Company may vote. Such a high level of ownership
by such persons or entities may have a significant effect in delaying, deferring
or preventing a change in control of the Company and may adversely affect the
voting and other rights of other holders of Common Stock. Certain provisions of
the Company's Certificate of Incorporation, 1994 Stock Option/Stock Issuance
Plan, Bylaws and Delaware law may also discourage certain transactions involving
a change in control of the Company. In addition to the foregoing, the ability of
the Company's
 
                                       18
<PAGE>
Board of Directors to issue preferred stock without further stockholder approval
could have the effect of delaying, deferring or preventing a change in control
of the Company.
 
VOLATILITY OF STOCK PRICE
 
    The Company believes that factors such as announcements of developments
related to the Company's business, fluctuations in the Company's operating
results, sales of the Company's Common Stock into the market place, failure to
meet or changes in analysts' expectations, natural disasters, outbreaks of
hostilities, general conditions in the semiconductor industry or the worldwide
economy, announcements of technological innovations or new products or
enhancements by the Company or its competitors, developments in patents or other
intellectual property rights and developments in the Company's relationships
with its customers and suppliers could cause the price of the Company's common
stock to fluctuate, perhaps substantially. In addition, in recent years the
stock market in general, and the market for shares of small capitalization
stocks in particular, have experienced extreme price fluctuations, which have
often been unrelated to the operating performance of affected companies. There
can be no assurance that the market price of the Company's common stock will not
experience significant fluctuations in the future, including fluctuations that
are unrelated to the Company's performance.
 
ITEM 2.  PROPERTIES
 
    The Company maintains its headquarters in San Jose, California in three
leased facilities, aggregating approximately 148,500 square feet, which contain
general administration and finance, marketing and sales, customer service and
support, manufacturing and research and development. The three buildings have
separate leases with two of the leases expiring on December 31, 1999 and the
third lease expiring on August 31, 1998.
 
    The Company also leases seven sales and support offices in the United States
in Austin, Texas; Dallas, Texas; Fort Washington, Pennsylvania; Rockaway, New
Jersey; Aloha, Oregon; Mesa, Arizona; and Hopewell, New York under leases with
terms of one to three years.
 
    Additionally, the Company leases sales and support offices in Korea, Japan,
Scotland, Singapore and Taiwan. Lease terms vary from two to ten years.
 
    The Company also leases two facilities totaling approximately 34,000 square
feet in Japan which is dedicated to the Company's LCD division (formerly called
Tekisco). One of the facilities totaling approximately 20,000 square feet is
used for administration, marketing and sales, customer service and support,
manufacturing and research and development. The lease on this facility expires
September 30, 1998. The other facility totaling approximately 14,000 square feet
was acquired in December 1995 to expand production capability. The lease on this
facility expires November 30, 1997.
 
    The Company believes that its existing facilities will adequately meet its
anticipated requirements for the next twelve months and that suitable additional
or substitute space will be available as needed.
 
ITEM 3.  LEGAL PROCEEDINGS
 
    The Company is not a party to any material litigation.
 
ITEM 4.  SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS
 
    No matters were submitted to a vote of security holders during the fourth
quarter ended September 30, 1996.
 
                                       19
<PAGE>
                      EXECUTIVE OFFICERS OF THE REGISTRANT
 
    The executive officers of the Company are as follows:
 
<TABLE>
<CAPTION>
NAME                           AGE                                POSITION
-------------------------      ---      ------------------------------------------------------------
<S>                        <C>          <C>
Monte M. Toole...........          65   Chairman of the Board
Dave Toole...............          41   Chief Executive Officer, President and Director
Avner Shelem.............          43   Vice President, General Manager, Engineering and Operations
Terry Gibson.............          43   Vice President, Finance and Chief Financial Officer
Jeannine Sargent.........          32   Vice President, Marketing and Customer Technology
Pascal Didier............          37   Vice President, Worldwide Sales and Customer Support
Ralph Kerns..............          50   Vice President, Technology
</TABLE>
 
    MONTE M. TOOLE founded the Company in March 1971 and has served as Chairman
of the Board since the Company's inception and as Chief Executive Officer from
inception to December 31, 1994. Between March 1971 and May 1993, Mr. Toole also
served as President of the Company. Prior to founding the Company, Mr. Toole was
a representative of semiconductor equipment manufacturers at Monte Toole and
Associates, Inc., a manager at Fairchild Semiconductor and a systems analyst at
IBM. From October 1991 to June 1993, Mr. Toole served on the Board of Directors
of Integrated Process Equipment Corporation, a semiconductor equipment company.
 
    DAVE TOOLE became the Company's President and Chief Operating Officer in May
1993, and became the Companys' Chief Executive Officer on December 31, 1994.
Prior to that time, Mr. Toole served as the Company's Vice President, Sales and
Marketing from October 1986 to April 1989 and has served as a Director since
April 1979. Mr. Toole also served as the Company's Vice President and General
Manager from April 1989 to May 1991 and as Vice President, Commercial Operations
from May 1991 to May 1993. Mr. Toole has held various other positions in
purchasing, manufacturing, marketing and sales since joining the Company in
1979. Prior to 1979, Mr. Toole was employed by Advanced Micro Devices, a
semiconductor manufacturer.
 
    AVNER SHELEM joined the Company as Vice President, Research, Development and
Engineering in March 1994 and was promoted to Vice President, General Manager,
Engineering and Operations in September 1996. Between December 1992 and March
1994, Mr. Shelem was a partner at Intertech Management Group, a management
consulting firm. From September 1990 to December 1992, Mr. Shelem served as
Chief Operating Officer of AG Associates, a manufacturer of rapid thermal
processing equipment. From January 1983 to September 1990, Mr. Shelem held
various positions at Intel Corporation, including Material and General Site
Services Manager, Lithography Manager, Diffusion Manager and Industrial
Engineering Manager.
 
    TERRY GIBSON became the Company's Vice President, Finance and Chief
Financial Officer in May 1996. Before joining GaSonics, Mr. Gibson had been
employed by Lam Research Corporation, since 1991 where he served as Vice
President, Corporate Controller. From 1990 to 1991, Mr. Gibson was the Corporate
Controller at Silicon Valley Group and from 1989 to 1990 served as Corporate
Controller of Flextronics, Inc. From 1983 to 1989, Mr. Gibson held various
financial management positions at National Semiconductor and prior to that began
his career with the independent public accounting firm of Deloitte, Haskins and
Sells.
 
    JEANNINE SARGENT became the Company's Vice President, Marketing and Customer
Technology in February 1996. Prior to joining GaSonics, Ms. Sargent was employed
by Tencor Instruments from August 1992 to January 1996 where she most recently
held the position of Director of Marketing. From October 1990 to July 1992 she
served as Technical Marketing and Applications Manager at Semi Test and from
 
                                       20
<PAGE>
August 1987 to September 1990 was a Senior Development and Integration Engineer
at Digital Equipment.
 
    PASCAL DIDIER joined the Company in May 1995 as Director of Asian Sales and
was promoted to Vice President of Worldwide Sales and Customer Support in June
1996. Prior to GaSonics, Mr. Didier had been employed since 1983 by Megatest
Corporation where he held various positions including European Technical
Manager, Director of International Operations and in June 1993, became Vice
President of International Operations.
 
    RALPH KERNS PH.D. became the Company's Vice President, Technology in October
1996. Prior to joining the Company, Dr. Kerns was employed by Lam Research from
July 1993 to September 1996, first as Director, then as Vice President of Lam's
Metal Etch Business Unit. Dr. Kerns came to Lam through its acquisition of
Drytek Incorporated in July 1993. Dr. Kerns was Drytek's Director of Technology
from February 1991 until the acquisition. Before that, Dr. Kerns held R&D
positions in wafer fabrication at Commodore Semiconductor Group and in materials
science at Solarex Corporation and Solar Energy Research Institute (now National
Renewable Energy Laboratory).
 
    The executive officers serve at the discretion of the Board of Directors,
until their successors are appointed. No family relationships exist among the
officers and directors, except Monte Toole and Dave Toole are father and son.
 
                                       21
<PAGE>
                                    PART II
 
ITEM 5.  MARKET FOR THE REGISTRANT'S COMMON EQUITY AND RELATED STOCKHOLDERS
         MATTERS
 
    The information required by this Item is incorporated by reference from page
13 of the Company's 1996 Annual Report to Stockholders.
 
ITEM 6.  SELECTED FINANCIAL DATA
 
    The information required by this Item is incorporated by reference from page
13 of the Company's 1996 Annual Report to Stockholders.
 
ITEM 7.  MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS
         OF OPERATIONS.
 
    The information required by this Item is incorporated by reference from
pages 14-17 of the Company's 1996 Annual Report to Stockholders.
 
ITEM 8.  FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA
 
    The Report of Independent Public Accountants and consolidated financial
statements required by this Item are incorporated by reference from pages 18-29
of the Company's 1996 Annual Report to Stockholders.
 
                                       22
<PAGE>
                                    PART III
 
    Certain information required by Part III is omitted from this Report in that
the Registrant intends to file a definitive proxy statement within 120 days
after the end of its fiscal year pursuant to Regulation 14A for its Annual
Meeting of Stockholders to be held March 3, 1997 ( the "Proxy Statement") and
the information included therein is incorporated herein by reference.
 
ITEM 10.  DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT
 
    The information concerning the Company's directors required by this Item is
incorporated by reference from "Election of Directors" in the Proxy Statement.
The information required by this item relating to the Company's executive
officers is included under the caption "Executive Officers of the Registrant" in
Part I of this Report on Form 10-K.
 
ITEM 11.  EXECUTIVE COMPENSATION
 
    The information required by this Item is incorporated by reference from the
Proxy Statement under the heading "Executive Compensation and Related
Information".
 
ITEM 12.  SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT
 
    The information required by this Item is incorporated by reference from the
Proxy Statement under the heading "Election of Directors" and "Ownership of
Securities".
 
ITEM 13.  CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS
 
    The information required by this Item is incorporated by reference from the
Proxy Statement under the heading "Certain Transactions".
 
                                       23
<PAGE>
                                    PART IV
 
ITEM 14.  EXHIBITS, FINANCIAL STATEMENTS AND REPORTS ON FORM 8-K
 
    (a) The following documents are filed as part of this Report on Form 10-K:
 
        (1) Financial Statements
 
            The following consolidated financial statements of GaSonics
            International Corporation are set forth in the Company's 1996 Annual
            Report to the Stockholders and are incorporated by reference hereto
            in Item 8:
 
<TABLE>
<CAPTION>
                                                                        ANNUAL REPORT
                                                                         PAGE NUMBER
                                                                       ---------------
<S>                                                                    <C>
Consolidated Balance Sheets--September 30, 1996 and 1995.............            18
Consolidated Statements of Operations--Years Ended September 30,
  1996, 1995 and 1994................................................            19
Consolidated Statements of Stockholders' Equity--Years Ended
  September 30, 1996, 1995 and 1994..................................            20
Consolidated Statements of Cash Flows--Years Ended September 30,
  1996, 1995 and 1994................................................            21
Notes to Consolidated Financial Statements...........................         22-28
Report of Independent Public Accountants.............................            29
</TABLE>
 
        (2) Financial Statement Schedules
 
            The following consolidated financial statement schedule is included
            herein:
 
<TABLE>
<CAPTION>
                                                                         PAGE NUMBER
                                                                       ---------------
<S>                                                                    <C>
Report of Independent Public Accountants on Schedule.................            28
Schedule II--Valuation and Qualifying Accounts.......................            29
</TABLE>
 
    Schedules other than those listed above have been omitted since they are
either not required, are not applicable, or the required information is shown in
the financial statements or related notes.
 
        (3) Exhibits
 
                                       24
<PAGE>
            The following exhibits are referenced or included in this report:
 
<TABLE>
<CAPTION>
 EXHIBITS                                                 DESCRIPTION
-----------  -----------------------------------------------------------------------------------------------------
<C>          <S>
       2.1(1) Form of Agreement and Plan of Merger between Gasonics International Corporation, a California
               corporation, and the Registrant
 
       2.2(1) Stock Purchase Agreement dated February 28, 1991 between Emerson Electric Company and the Registrant
 
       2.3(5) Asset Purchase Agreement dated as of July 30, 1995 among the Registrant, GaSonics International
               Japan, K.K., Tekisco, Inc. and Kishimoto Sangyo Co. Ltd.
 
       2.4(5) Stock Purchase Agreement dated as of July 30, 1995 between the Registrant and Kishimoto Sangyo Co.
               Ltd.
 
       2.5(5) Commission Agreement dated as of July 30, 1995 between the Registrant and Kishimoto Sangyo Co. Ltd.
 
       3.1(1) Certificate of Incorporation of the Registrant
 
       3.2(1) Bylaws of the Registrant
 
       3.3   Amended and Restated Bylaws of the Registrant
 
       4.1(1) Form of Common Stock Certificate
 
      10.1(1) Form of Indemnification Agreement between the Company and each of its officers and directors
 
      10.2(8) 1994 Stock Option/Stock Issuance Plan and forms of agreements thereunder, as amended and restated
               effective February 1, 1996
 
      10.3(8) 1994 Employee Stock Purchase Plan, as amended and restated effective November 4, 1996
 
      10.4(1) Form of Light Industrial Lease between Teachers Insurance and Annuity Association of America and the
               Registrant for office space at 2730 Junction Avenue, San Jose, California
 
      10.5(1) Secured Promissory Note dated February 28, 1991 in the principal amount of $4,500,000 issued by the
               Registrant and Branson International Plasma Corporation in favor of Emerson Electric Company
 
      10.6(1) Promissory Note dated November 10, 1993 in the principal amount of $359,375 issued by the Registrant
               in favor of Robert Champagne
 
      10.7(1) Continuing Guaranty dated November 10, 1993 in the principal amount of $359,375 issued by the
               Registrant in favor of Robert Champagne
 
      10.8(1) Promissory Note dated November 10, 1993 in the principal amount of $339,999.60 issued by Dave Toole
               in favor of the Registrant
 
      10.9(1) Demand Note dated November 30, 1993 in the principal amount of $62,500 issued by Dave Toole in favor
               of the Registrant
 
      10.10(1) Sale of Shares Pursuant to Redemption Agreement dated November 10, 1993 between Robert Champagne and
               the Registrant
 
      10.11(1) Non-Compete Agreement dated as of November 10, 1993 and Addendum to Non-Compete Agreement dated as of
               November 18, 1993 between Robert Champagne and the Registrant
 
      10.12(1) Credit Agreement dated August 6, 1993 between Union Bank, International Plasma Corporation and the
               Registrant
</TABLE>
 
                                       25
<PAGE>
<TABLE>
<CAPTION>
 EXHIBITS                                                 DESCRIPTION
-----------  -----------------------------------------------------------------------------------------------------
<C>          <S>
      10.13(2) Business Loan Agreement dated April 28, 1994 between Registrant and Union Bank and related Promissory
               Note
 
      10.14(3) Lease Agreement dated November 14, 1994 between Registrant and Realtech Properties I, L.P.
 
      10.15(4) Loan Agreement dated April 19, 1995 between Registrant and Union Bank, a California banking
               corporation
 
      10.16(4) Lease Agreement dated June 5, 1995 between Registrant and Orchard Investment Company
 
      10.17(6) Underwriting Agreement dated March 21, 1994 by and among the Registrant, the underwriters named
               therein and the selling stockholders named therein
 
      10.18(7) Underwriting Agreement dated March 9, 1995 by and among the Registrant, the underwriters named
               therein and the selling stockholders named therein
 
      10.19(8) Continuing Guarantee Agreement dated July 31, 1995, executed by the Registrant in favor of the Bank
               of Tokyo, Ltd.
 
      10.20(9) Loan Agreement dated March 4, 1996 between Registrant and Union Bank
 
      13     Portions of the Annual Report to Stockholders for the year ended September 30, 1996
               which are expressly incorporated herein by reference
 
      16.1(1) Letter from Ernst & Young dated March 8, 1994 regarding the change in the Certifying Accountant of
               the Registrant
 
      21.1   List of Subsidiaries of the Registrant
 
      23.1   Consent of Independent Public Accountants
 
      24.1(1) Power of Attorney (Included on signature page)
 
      27     Financial Data Schedule
</TABLE>
 
------------------------
 
(1) Incorporated by reference to identically numbered exhibits included in
    Registrant's Registration Statement on Form S-1 (File No. 33-74872) declared
    effective with the Securities and Exchange Commission on March 21, 1994.
 
(2) Incorporated by reference to identically numbered exhibit included in
    Registrant's Report on Form 10-Q for the quarter ended June 30, 1994.
 
(3) Incorporated by reference to an exhibit in Registrant's Report on Form 10-Q
    for the quarter ended December 31, 1994.
 
(4) Incorporated by reference to exhibits included in Registrant's Report on
    Form 10-Q for the quarter ended June 30, 1995.
 
(5) Incorporated by reference to exhibits filed with Registrant's Current Report
    on Form 8-K filed with the Securities and Exchange Commission on August 24,
    1995.
 
(6) Incorporated by reference to an exhibit in Registrant's Registration
    Statement on Form S-1 (File No. 33-74872) declared effective with the
    Securities and Exchange Commission on March 21, 1994.
 
(7) Incorporated by reference to an exhibit in Registrant's Registration
    Statement on Form S-1 (File No. 33-89636) declared effective with the
    Securities and Exchange Commission on March 9, 1995.
 
(8) Incorporated by reference to exhibits filed with the Registrant's Annual
    Report on Form 10-K for the year ended September 30, 1995.
 
(9) Incorporated by reference to an exhibit included in Registrant's Report on
    Form 10-Q for the quarter ended March 31, 1996.
 
                                       26
<PAGE>
    (b) Reports on Form 8-K.
 
        No reports on Form 8-K were filed during the fourth quarter ended
        September 30, 1996.
 
    (c) Exhibits. See list of exhibits under (a) (3) above.
 
    (d) Financial Statement Schedules. See list of schedules under (a) (2)
above.
 
                                       27
<PAGE>
                                   SIGNATURES
 
    Pursuant to the requirements of Section 13 or 15 (d) of the Securities
Exchange Act of 1934, the Registrant has duly caused this Report to be signed on
its behalf by the undersigned, thereunto duly authorized.
 
Date:  December 20, 1996        GASONICS INTERNATIONAL CORPORATION
 
                                By:                /s/ DAVE TOOLE
                                     -----------------------------------------
                                                     Dave Toole
                                        PRESIDENT & CHIEF EXECUTIVE OFFICER
 
                               POWER OF ATTORNEY
 
    KNOW ALL MEN BY THESE PRESENTS, that each person whose signature appears
below constitutes and appoints Monte M. Toole and David J. Toole, jointly and
severally, his attorneys-in-fact, each with the power of substitution, for him
in any and all capacities, to sign any amendments to the Report on Form 10-K and
to file the same, with exhibits thereto and other documents in connection
therewith, with the Securities and Exchange Commission, hereby ratifying and
confirming all that each of said attorney-in-fact, or his substitute or
substitutes, may do or cause to be done by virtue hereof.
 
    Pursuant to the requirements of the Securities Exchange Act of 1934, this
Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated below:
 
          SIGNATURE                       TITLE                    DATE
------------------------------  --------------------------  -------------------
 
      /s/ MONTE M. TOOLE
------------------------------  Chairman of the Board of     December 20, 1996
        Monte M. Toole            Directors
 
                                Chief Executive Officer,
        /s/ DAVE TOOLE            President and Director
------------------------------    (Principal Executive       December 20, 1996
          Dave Toole              Officer)
 
                                Vice President, Finance
     /s/ TERRY R. GIBSON          and Chief Financial
------------------------------    Officer (Principal         December 20, 1996
       Terry R. Gibson            Financial and Accounting
                                  Officer)
 
   /s/ KENNETH L. SCHROEDER
------------------------------  Director                     December 20, 1996
     Kenneth L. Schroeder
 
  /s/ F. JOSEPH VAN POPPELEN
------------------------------  Director                     December 20, 1996
    F. Joseph Van Poppelen
 
                                       27
<PAGE>
              REPORT OF INDEPENDENT PUBLIC ACCOUNTANTS ON SCHEDULE
 
To GaSonics International Corporation:
 
    We have audited in accordance with generally accepted auditing standards,
the financial statements included in GaSonics International Corporation's Annual
Report to Stockholders incorporated by reference in this Form 10-K, and have
issued our report thereon dated November 4, 1996. Our audit was made for the
purpose of forming an opinion on those statements taken as a whole. The schedule
listed in the index under item 14(a)(2) is the responsibililty of the Company's
management and is presented for purposes of complying with the Securities and
Exchange Commission rules and is not part of the basic financial statements.
This schedule has been subjected to the auditing procedures applied in the audit
of the basic financial statements and, in our opinion, fairly states in all
material respects the financial data required to be set forth therein in
relation to the basic financial statements taken as a whole.
 
/s/ ARTHUR ANDERSEN LLP
 
ARTHUR ANDERSEN LLP
 
San Jose, California
November 4, 1996
 
                                       28
<PAGE>
                                                                     SCHEDULE II
 
                       GASONICS INTERNATIONAL CORPORATION
 
                       VALUATION AND QUALIFYING ACCOUNTS
 
                                 (IN THOUSANDS)
 
<TABLE>
<CAPTION>
                                                      BALANCE AT    CHARGED TO    CHARGED TO                   BALANCE
                                                     BEGINNING OF    COSTS AND       OTHER                     AT END
DESCRIPTIONS                                            PERIOD       EXPENSES      ACCOUNTS     DEDUCTIONS    OF PERIOD
---------------------------------------------------  -------------  -----------  -------------  -----------  -----------
<S>                                                  <C>            <C>          <C>            <C>          <C>
ALLOWANCE FOR DOUBTFUL ACCOUNTS
Years Ended September 30,:
  1994.............................................    $     154     $     239     $      --     $     105    $     288
  1995.............................................    $     288     $     179     $      --     $      98    $     369
  1996.............................................    $     369     $     240     $       2     $      --    $     611
 
INVENTORY RESERVES
Years Ended September 30,:
  1994.............................................    $     681     $     564     $      --     $      44    $   1,201
  1995.............................................    $   1,201     $   1,212     $      --     $     851    $   1,562
  1996.............................................    $   1,562     $   2,266     $      --     $   1,593    $   2,235
</TABLE>
 
                                       29