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                                                                     EXHIBIT 4.3

             1994 EMPLOYEE STOCK OPTION PLAN OF ETEC SYSTEMS, INC.
             -----------------------------------------------------

  SECTION 1.    ESTABLISHMENT AND PURPOSE.
  ---------------------------------------

          The Plan was established in 1994 to offer selected employees,
directors and consultants an opportunity to acquire a proprietary interest in
the success of the Company, or to increase such interest, by purchasing Shares
of the Company's Common Stock. The Plan provides for the grant of Options to
purchase Shares. Options granted under the Plan may include Nonstatutory Options
as well as ISOs intended to qualify under section 422 of the Code.

  SECTION 2.    DEFINITIONS.
  -------------------------

          (a)  "Board of Directors" shall mean the Board of Directors of the
                ------------------
Company,as constituted from time to time.

          (b)  "Code" shall mean the Internal Revenue Code of 1986, as amended.
                ----

          (c)  "Committee" shall mean the Compensation Committee of the Board of
                ---------
Directors, as described in Section 3(a).

          (d)  "Company" shall mean Etec Systems, Inc., a Nevada corporation.
                -------

          (e)  "Disability" shall mean that the Optionee is unable to engage in
                ----------
any substantial gainful activity by reason of any medically determinable
physical or mental impairment which can be expected to result in death or which
has lasted, or can be expected to last, for a continuous period of not less than
twelve months.

          (f)  "Employee" shall mean any individual who is (i) a common-law
                --------
employee of the Company or of a Subsidiary, (ii) a member of the Board of
Directors, or (iii) an independent contractor who performs services for the
Company or a Subsidiary. Service as a member of the Board of Directors or as an
independent contractor shall be considered employment for all purposes of the
Plan except the second sentence of Section 4(a).

          (g)  "Exercise Price" shall mean the amount for which one Share may be
                --------------
purchased upon exercise of an Option, as specified by the Committee in the
applicable Stock Option Agreement.

          (h)  "Fair Market Value" shall mean the fair market value of a Share,
                -----------------
as determined by the Committee in good faith. Such determination shall be
conclusive and binding on all persons.

          (i)  "ISO" shall mean an employee incentive stock option described in
                ---
section 422(b) of the Code.

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          (j)  "Nonstatutory option" shall mean an employee stock option not
                -------------------
described in sections 422(b) or 423(b) of the Code.

          (k)  "Option" shall mean an ISO or Nonstatutory Option granted under
                ------
the Plan and entitling the holder to purchase Shares.

          (l)  "Optionee" shall mean an individual who holds an Option.
                --------

          (m)  "Plan" shall mean this 1994 Employee Stock Option Plan of Etec
                ----
Systems, Inc.

          (n)  "Service" shall mean service as an Employee.
                -------

          (o)  "Share" shall mean one share of Stock, as adjusted in accordance
                -----
with Section 8 (if applicable).

          (p)  "Stock" shall mean the Common Stock of the Company.
                -----

          (q)  "Stock Option Agreement" shall mean the agreement between the
                ----------------------
Company and an Optionee which contains the terms, conditions and restrictions
pertaining to his Option.

          (r)  "Subsidiary" shall mean any corporation, if the Company and/or
                ----------
one or more other Subsidiaries own not less than 50 percent of the total
combined voting power of all classes of outstanding stock of such corporation. A
corporation that attains the status of a Subsidiary on a date after the adoption
of the Plan shall be considered a Subsidiary commencing as of such date.

     SECTION 3.    ADMINISTRATION.
     ----------------------------

          (a)  Committee Membership. The Plan shall be administered by the
               --------------------
Committee, which shall consist of members of the Board of Directors. The members
of the Committee shall be appointed by the Board of Directors. If no Committee
has been appointed, the entire Board of Directors shall constitute the
Committee.

          (b)  Committee Procedures. The Board of Directors shall designate one
               --------------------
of the members of the Committee as chairman. The Committee may hold meetings at
such times and places as it shall determine. The acts of a majority of the
Committee members present at meetings at which a quorum exists, or acts reduced
to and approved in writing by all Committee members, shall be valid acts of the
Committee.

          (c)  Committee Responsibilities. Subject to the provisions of the
               --------------------------
Plan, the Committee shall have full authority and discretion to take the
following actions:

               (i)  To interpret the Plan and to apply its provisions;

               (ii) To adopt, amend or rescind rules, procedures and forms
          relating to the Plan;

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               (iii)  To authorize any person to execute, on behalf of the
     Company, any instrument required to carry out the purposes of the Plan;

               (iv)   To determine when Options are to be granted under the
     Plan;

               (v)    To select the Optionees;

               (vi)   To determine the number of Shares to be made subject to
     each Option;

               (vii)  To prescribe the terms and conditions of each Option,
     including (without limitation) the Exercise Price, to determine whether
     such Option is to be classified as an ISO or as a Nonstatutory Option, and
     to specify the provisions of the Stock Option Agreement relating to such
     Option;

               (viii) To amend any outstanding Stock Option Agreement, subject
     to applicable legal restrictions and to the consent of the Optionee who
     entered into such agreement; and

               (ix)   To take any other actions deemed necessary or advisable
     for the administration of the Plan.

          All decisions, interpretations and other actions of the Committee
shall be final and binding on all Optionees and all persons deriving their
rights from an Optionee. No member of the Committee shall be liable for any
action that he has taken or has failed to take in good faith with respect to the
Plan or any Option to acquire Shares under the Plan.

     SECTION 4.    ELIGIBILITY.
     -------------------------

          (a)  General Rule. Only Employees shall be eligible for designation as
               ------------
Optionees by the Committee. In addition, only individuals who are employed as
common-law employees by the Company or a Subsidiary shall be eligible for the
grant of ISOs.

          (b)  Ten-Percent Shareholders. An Employee who owns more than 10
               ------------------------
percent of the total combined voting power of all classes of outstanding stock
of the Company or any of its Subsidiaries shall not be eligible for designation
as an Optionee unless (i) the Exercise Price is at least 110 percent of the Fair
Market Value of a Share on the date of grant and (ii) in the case of an ISO, the
Option granted by its term is not exercisable after the expiration of five years
from the date of grant.

          (c)  Attribution Rules. For purposes of Subsection (b) above, in
               -----------------
determining stock ownership, an Employee shall be deemed to own the stock owned,
directly or indirectly, by or for his brothers, sisters, spouse, ancestors and
lineal descendants. Stock owned, directly or indirectly, by or for a
corporation, partnership, estate or trust shall be deemed to be owned
proportionately by or for its shareholders, partners or beneficiaries. Stock
with respect to which such Employee holds an option shall not be counted.

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          (d)  Outstanding Stock. For purposes of Subsection (b) above,
               -----------------
"outstanding stock" shall include all stock actually issued and outstanding
immediately after the grant. "Outstanding stock" shall not include shares
authorized for issuance under outstanding options held by the Employee or by any
other person.


     SECTION 5.    STOCK SUBJECT TO PLAN.
     -----------------------------------

          (a)  Basic Limitation. Shares offered under the Plan shall be
               ----------------
authorized but unissued Shares and treasury stock. The aggregate number of
Shares which may be issued under the Plan shall not exceed 448,374 Shares,
subject to adjustment pursuant to Section 8. The number of Shares which are
subject to Options outstanding at any time under the Plan shall not exceed the
number of Shares which then remain available for issuance under the Plan. The
Company, during the term of the Plan, shall at all times reserve and keep
available sufficient Shares to satisfy the requirements of the Plan.

          (b)  Additional Shares. In the event that any outstanding Option for
               -----------------
any reason expires or is cancelled or otherwise terminated, the Shares allocable
to the unexercised portion of such Option shall again be available for the
purposes of the Plan. In the event that Shares issued under the Plan are
reacquired by the Company pursuant to a forfeiture provision, a right of
repurchase, a right of first refusal or a transaction under Section 7(b), such
Shares shall again be available for the purposes of the Plan.

     SECTION 6.    TERMS AND CONDITIONS OF OPTIONS.
     ---------------------------------------------

          (a)  Stock Option Agreement. Each grant of an Option under the Plan
               ----------------------
shall be evidenced by a Stock Option Agreement between the Optionee and the
Company. Such Option shall be subject to all applicable terms and conditions of
the Plan and may be subject to any other terms and conditions which are not
inconsistent with the Plan and which the Committee deems appropriate for
inclusion in a Stock Option Agreement. The provisions of the various Stock
Option Agreements entered into under the Plan need not be identical.

          (b)  Number of Shares. Each Stock Option Agreement shall specify the
               ----------------
number of Shares that are subject to the Option and shall provide for the
adjustment of such number in accordance with Section 8. The Stock Option
Agreement shall also specify whether the Option is an ISO or a Nonstatutory
Option.

          (c)  Exercise Price. Each Stock Option Agreement shall specify the
               --------------
Exercise Price. The Exercise Price shall not be less than 100 percent of the
Fair Market Value of a Share on the date of grant, and, if applicable, shall be
subject to the additional limitation provided in Section 4(b). Subject to the
preceding sentence, the Exercise Price under any Option shall be determined by
the Committee at its sole discretion. The Exercise Price shall be payable in a
form described in Section 7.

          (d)  Withholding Taxes. As a condition to the exercise of an Option,
               -----------------
the Optionee shall make such arrangements as the Committee may require for the
satisfaction of any federal, state

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or local withholding tax obligations that may arise in connection with such
exercise. The Optionee shall also make such arrangements as the Committee may
require for the satisfaction of any federal, state or local withholding tax
obligations that may arise in connection with the disposition of Shares acquired
by exercising an Option.

          (e)  Exercisability and Term. Each Stock Option Agreement shall
               -----------------------
specify the date when all or any installment of the Option is to become
exercisable. An Option shall become exercisable at least as rapidly as set forth
in the following schedule:



          Anniversary of                           Minimum Percentage
          Date of Grant                               Exercisable
          --------------                              -----------
          First......................................... 20%
          Second........................................ 40%
          Third......................................... 60%
          Fourth........................................ 80%
          Fifth.........................................100%

Subject to the preceding sentence, the vesting of any Option shall be determined
by the Committee at its sole discretion. The Stock Option Agreement shall also
specify the term of the Option. The term shall not exceed 10 years from the date
of grant, except as otherwise provided in Section 4(b). Subject to the preceding
sentence, the Committee at its sole discretion shall determine when an Option is
to expire.

          (f)  Nontransferability. During an Optionee's lifetime, his Option(s)
               ------------------
shall be exercisable only by him and shall not be transferable. In the event of
an Optionee's death, his Option(s) shall not be transferable other than by will
or by the laws of descent and distribution.

          (g)  Termination of Service (Except by Death). If an Optionee's
               ----------------------------------------
Service terminates for any reason other than his death, then his Option(s) shall
expire on the earliest of the following occasions:

               (i)    The expiration date determined pursuant to Subsection (e)
above;

               (ii)   The date 60 days after the termination of his Service for
     any reason other than Disability; or

               (iii)  The date six months after the termination of his Service
by reason of Disability.

The Optionee may exercise all or part of his Option(s) at any time before the
expiration of such Option(s) under the preceding sentence, but only to the
extent that such Option(s) had become exercisable before his Service terminated
or became exercisable as a result of the termination. The balance of such
Option(s) shall lapse when the Optionee's Service terminates. In the event that
the

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Optionee dies after the termination of his Service but before the expiration
of his Option(s), all or part of such Option(s) may be exercised (prior to
expiration) by the executors or administrators of the Optionee's estate or by
any person who has acquired such Option(s) directly from him by bequest or
inheritance, but only to the extent that such Option(s) had become exercisable
before his Service terminated or became exercisable as a result of the
termination.

          (h)  Leaves of Absence. For purposes of Subsection (g) above, Service
               -----------------
shall be deemed to continue while the Optionee is on military leave, sick leave
or other bona fide leave of absence (as determined by the Committee). The
foregoing notwithstanding, in the case of an ISO granted under the Plan, Service
shall not be deemed to continue beyond the first 90 days of such leave, unless
the Optionee's reemployment rights are guaranteed by statute or by contract.

          (i)  Death of Optionee. If an Optionee dies while he is in Service,
               -----------------
then his Option(s) shall expire on the earlier of the following dates:

               (i)  The expiration date determined pursuant to Subsection (e)
               above; or

               (ii) The date six months after his death.

All or part of the Optionee's Option(s) may be exercised at any time before the
expiration of such Option(s) under the preceding sentence by the executors or
administrators of his estate or by any person who has acquired such Option(s)
directly from him by bequest or inheritance, but only to the extent that such
Option(s) had become exercisable before his death or became exercisable as a
result of his death.  The balance of such Option(s) shall lapse when the
Optionee dies.

          (j)  No Rights as a Shareholder. An Optionee, or a transferee of an
               --------------------------
Optionee, shall have no rights as a shareholder with respect to any Shares
covered by his Option until the date of the issuance of a stock certificate for
such Shares. No adjustments shall be made, except as provided in Section 8.

          (k)  Modification, Extension and Renewal of Options. Within the
               ----------------------------------------------
limitations of the Plan, the Committee may modify, extend or renew outstanding
Options or may accept the cancellation of outstanding Options (to the extent not
previously exercised) in return for the grant of new Options at the same or a
different price. The foregoing notwithstanding, no modification of an Option
shall, without the consent of the Optionee, impair his rights or increase his
obligations under such Option.

          (l)  Restrictions on Transfer of Shares. Any Shares issued upon
               ----------------------------------
exercise of an Option shall be subject to such special forfeiture conditions,
rights of repurchase, rights of first refusal and other transfer restrictions as
the Committee may determine. Such restrictions shall be set forth in the
applicable Stock Option Agreement or in any agreement referred to therein and
shall apply in addition to any general restrictions that may apply to all
holders of Shares. Any service-based vesting conditions shall not be less rapid
than the schedule set forth in Subsection (e) above.

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     SECTION 7. PAYMENT FOR SHARES.
     ------------------------------

          (a)  General Rule. The entire Exercise Price of Shares issued under
               ------------
the Plan shall be payable in cash at the time when such Shares are purchased,
except as provided in Subsection (b) below.

          (b)  Surrender of Stock. To the extent that a Stock Option Agreement
               ------------------
so provides, payment may be made all or in part with Shares which have already
and which are surrendered to the Company in good form for transfer. Such Shares
shall be valued at their Fair Market Value on the date when the new Shares are
purchased under the Plan.

     SECTION 8. ADJUSTMENT OF SHARES.
     --------------------------------

          (a)  General. In the event of a subdivision of the outstanding Stock,
               -------
a declaration of a dividend payable in Shares, a declaration of a dividend
payable in a form other than Shares in an amount that has a material effect on
the value of Shares, a combination or consolidation of the outstanding Stock (by
reclassification or otherwise) into a lesser number of Shares, a
recapitalization or a similar occurrence, the Committee shall make appropriate
adjustments in one or more of (i) the number of Shares available for future
grants under Section 5, (ii) the number of Shares covered by each outstanding
Option or (iii) the Exercise Price under each outstanding Option.

          (b)  Reorganizations. In the event that the Company is a party to a
               ---------------
merger or other reorganization, outstanding Options shall be subject to the
agreement of merger or reorganization. Such agreement shall provide for the
assumption of outstanding Options by the surviving corporation or its parent or
for their continuation by the Company (if the Company is a surviving
corporation); provided, however, that if assumption on continuation of the
outstanding Options is not provided by said agreement, then the Committee shall
have the option of offering the payment of a cash settlement equal to the
difference between the amount to be paid for one Share under such agreement and
the Exercise Price, in all cases without the Optionees' consent.

          (c)  Reservation of Rights. Except as provided in this Section 8, an
               ---------------------
Optionee shall have no rights by reason of any subdivision or consolidation of
shares of stock of any class, the payment of any dividend or any other increase
or decrease in the number of shares of stock of any class. Any issue by the
Company of shares of stock of any class, or securities convertible into shares
of stock of any class, shall not affect, and no adjustment by reason thereof
shall be made with respect to, the number or Exercise Price of Shares subject to
an Option. The grant of an Option pursuant to the Plan shall not affect in any
way the right or power of the Company to make adjustments, reclassifications,
reorganizations or changes of its capital or business structure, to merge or
consolidate or to dissolve, liquidate, sell or transfer all or any part of its
business or assets.

     SECTION 9. LEGAL REQUIREMENTS.
     ------------------------------

     Shares shall not be issued under the Plan unless the issuance and delivery
of such Shares complies with (or is exempt from) all applicable requirements of
law, including (without limitation) the Securities Act of 1933, as amended, the
rules and regulations promulgated thereunder, state

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securities laws and regulations, and the regulations of any stock exchange on
which the Company's securities may then be listed.

     SECTION 10. NO EMPLOYMENT RIGHTS.
     ---------------------------------

     No provision of the Plan, nor any right or Option granted under the Plan,
shall be construed to give any person any right to become, to be treated as, or
to remain an Employee.  The Company and its Subsidiaries reserve the right to
terminate any person's Service at any time and for any reason.

     SECTION 11. DURATION AND AMENDMENTS.
     ------------------------------------

          (a)  Term of the Plan. The Plan, as set forth herein, shall become
               ----------------
effective on June 7, 1994 subject to the approval of the Company's shareholders.
In the event that the shareholders fail to approve the Plan within 12 months
after its adoption by the Board of Directors, any Option grants already made
shall be null and void, and no additional Option grants shall be made after such
date. The Plan shall terminate automatically 10 years after its adoption by the
Board of Directors and may be terminated on any earlier date pursuant to
Subsection (b) below.

          (b)  Right to Amend or Terminate the Plan. The Board of Directors may
               ------------------------------------
amend, suspend or terminate the Plan at any time and for any reason; provided,
however, that any amendment of the Plan which increases the number of Shares
available for issuance under the Plan (except as provided in Section 8), or
which materially changes the class of persons who are eligible for the grant of
ISOs, shall be subject to the approval of the Company's shareholders.
Shareholder approval shall not be required for any other amendment of the Plan.

          (c)  Effect of Amendment or Termination. No Shares shall be issued or
               ----------------------------------
sold under the Plan after the termination thereof, except upon exercise of an
Option granted prior to such termination. The termination of the Plan, or any
amendment thereof, shall not affect any Option previously granted under the
Plan.

     SECTION 12. EXECUTION.
     ----------------------

     To record the adoption of the Plan by the Board of Directors on June 7,
1994, the Company has caused its authorized officer to execute the same.

Etec Systems, Inc.

By /s/ Stephen E. Cooper
   ---------------------
   Chief Executive Officer

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                             AMENDMENT NO. 1 TO THE
                               ETEC SYSTEMS, INC.
                        1994 EMPLOYEE STOCK OPTION PLAN

     ETEC SYSTEMS, INC., having established the Etec Systems, Inc. 1994 Employee
Stock Option Plan (the "Plan"), hereby amends the Plan, effective as of March
29, 2000 as follows:

          1.    Section 11 of the Plan is hereby amended in its entirety as
follows:

                SECTION 11. TERM OF THE PLAN.  In connection with the merger
                ----------------------------
     (the "Merger") of Etec Systems, Inc. ("Etec") and Boston Acquisition Sub,
     Inc. ("Boston"), a Nevada corporation and a wholly-owned subsidiary of
     Applied Materials, Inc. ("AMAT"), Options previously granted to Optionees
     under the Plan that remain outstanding as of March 29, 2000 (the
     "Outstanding Options"), have been modified pursuant to the Agreement and
     Plan of Reorganization and Merger dated as of January 12, 2000 (the "Merger
     Agreement"), among Etec, Boston and AMAT, so as to be exercisable only into
     shares of common stock of AMAT, par value $0.01 per share (the "Stock"),
     all as set forth in the Merger Agreement and subject to its terms and
     conditions. Effective as of March 29, 2000, except with respect to the
     Outstanding Options, the Plan is terminated. Accordingly no Shares remain
     available for future grant under the Plan, other than pursuant to the
     Outstanding Options.

          2.    Section 2.(c) of the Plan is amended in its entirety as follows:

                2.(c) "Committee" shall mean the Stock Option and Compensation
                       ---------
Committee of the Board of Directors of AMAT.

          3.    Section 2.(p) of the Plan is amended in its entirety as follows:

                2.(p) "Stock" shall mean the Common Stock of Applied Materials,
                       -----
Inc., a Delaware company.

          4.    Section 3.(a) and 3.(b) are hereby amended in their entirety to
read as follows, and each remaining provision in Section 3 shall be renumbered
accordingly:

                3.(a) Administration. The Plan shall be administered by the
                      --------------
Stock Option and Compensation Committee of the Board of Directors of AMAT. As
used throughout this Plan, the "Board" and "Committee" shall mean the Stock
Option and Compensation Committee of the Board of Directors of AMAT.

          5.    Section 4 is hereby amended in its entirety to read as follows:

                SECTION 4. NO FURTHER OPTION GRANTS.  Effective March 29, 2000,
                -----------------------------------
except with respect to the Outstanding Options, the Plan is terminated.
Accordingly, no further Options shall be granted under the Plan. Optionees
holding Outstanding Options may continue to exercise such Outstanding Options in
accordance with their terms, subject to the terms and conditions of the Merger
Agreement.

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          6.    Section 5 is hereby amended in its entirety to read as follows:

                SECTION 5. STOCK SUBJECT TO PLAN. AMAT has reserved
                --------------------------------
such number of Shares as are necessary to satisfy the Outstanding Options.

          7.    Section 12 is hereby amended by changing its title to "Execution
                                                                       ---------
and Termination" and by adding the following sentence to the end thereto to read
---------------
as follows:

     Except with respect to the Outstanding Options, the Plan shall terminate
effective as of March 29, 2000.

     IN WITNESS WHEREOF, Etec Systems, Inc., by the officer identified below,
who has been duly authorized by the Board of Directors of the Company, has
executed this Amendment No. 1 on the date indicated below.

                                                ETEC SYSTEMS, INC.

                                                By: ____________________


                                                Title: _________________

                                                Date: __________________

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