<PAGE>
                                                                     EXHIBIT 4.1

                               PURCHASE AGREEMENT


                  THIS AGREEMENT is made as of the 4th day of April, 2002, by
and between FSI International, Inc., a corporation organized under the laws of
the State of Minnesota (the "Company"), with its principal offices at 3455 Lyman
Boulevard, Chaska, Minnesota 55318-3052, and the purchaser whose name and
address is set forth on the signature page hereof (the "Purchaser").

                  IN CONSIDERATION of the mutual covenants contained in this
Agreement, the Company and the Purchaser agree as follows:

                  SECTION 1. Authorization of Sale of the Shares. Subject to the
terms and conditions of this Agreement, the Company has authorized the sale of
up to 4,000,000 shares (the "Shares") of common stock, no par value per share
(the "Common Stock"), of the Company. The Company reserves the right to increase
or decrease the number of shares of Common Stock sold in this private placement
prior to the Closing Date.

                  SECTION 2. Agreement to Sell and Purchase the Shares. At the
Closing (as defined in Section 3), the Company will sell to the Purchaser and
the Purchaser will buy from the Company, upon the terms and conditions
hereinafter set forth, the number of Shares (and at the purchase price) shown
below:

                                         Price Per
       Number to Be                      Share In                   Aggregate
        Purchased                        Dollars                      Price
        ---------                        -------                      -----




                  The Company proposes to enter into this same form of purchase
agreement with certain other investors (the "Other Purchasers") and expects to
complete sales of the Shares to them. The Purchaser and the Other Purchasers are
hereinafter sometimes collectively referred to as the "Purchasers," and this
Agreement and the agreements executed by the Other Purchasers are hereinafter
sometimes collectively referred to as the "Agreements." The term "Placement
Agents" shall mean Lehman Brothers Inc. and Needham & Company, Inc.

                  SECTION 3. Delivery of the Shares at the Closing. The
completion of the purchase and sale of the Shares (the "Closing") shall occur at
the offices of Stroock & Stroock & Lavan LLP, 180 Maiden Lane, New York, New
York 10038 as soon as practicable and as agreed by the parties hereto within
three business days following the execution of the Agreements, or on such later
date or at such different location as the parties shall agree in writing, but
not prior to the date that the conditions for Closing set forth below have been
satisfied or waived by the appropriate party (the "Closing Date"). The Closing
shall occur at a time to be agreed upon by


<PAGE>

the Company and the Placement Agents and of which the Purchasers will be
notified by facsimile transmission or otherwise.

                  At the Closing, the Company shall deliver to the Purchaser one
or more stock certificates registered in the name of the Purchaser, or in such
nominee name(s) as designated by the Purchaser in writing, representing the
number of Shares set forth in Section 2 above and bearing an appropriate legend
referring to the fact that the Shares were sold in reliance upon the exemption
from registration under the Securities Act of 1933, as amended (the "Securities
Act") provided by Section 4(2) thereof and Rule 506 thereunder. The name(s) in
which the stock certificates are to be registered are set forth in the Stock
Certificate Questionnaire attached hereto as part of Appendix I. The Company's
obligation to complete the purchase and sale of the Shares and deliver such
stock certificate(s) to the Purchaser at the Closing shall be subject to the
following conditions, any one or more of which may be waived by the Company: (a)
receipt by the Company of same-day funds in the full amount of the purchase
price for the Shares being purchased hereunder; (b) completion of the purchases
and sales under the Agreements with all of the Other Purchasers; and (c) the
accuracy of the representations and warranties (as if such representations and
warranties were made on the Closing Date) made by the Purchasers and the
fulfillment of those undertakings of the Purchasers to be fulfilled prior to the
Closing. The Purchaser's obligation to accept delivery of such stock
certificate(s) and to pay for the Shares evidenced thereby shall be subject to
the conditions: (1) that the representations and warranties made by the Company
herein are accurate as of the Closing Date; (2) that the Company has fulfilled
all undertakings to be fulfilled prior to the Closing; (3) that the Closing Date
shall occur on a date that is not later than April 5, 2002; and (4) that the
Common Stock shall be quoted on the Nasdaq National Market System. The
Purchaser's obligations hereunder are expressly conditioned on the purchase by
the Other Purchasers of Shares having an aggregate purchase price of at least
$20,000,000.


SECTION 4. Representations, Warranties and Covenants of the Company. The Company
hereby represents and warrants to, and covenants with, the Purchaser as follows:

                  4.1 Organization and Qualification. The Company is a
corporation duly incorporated, validly existing and in good standing under the
laws of the State of Minnesota and the Company is qualified to do business as a
foreign corporation in each jurisdiction in which qualification is required,
except where failure to so qualify would not reasonably be expected to have a
material adverse effect upon the business, financial condition, properties or
operations of the Company and its subsidiaries, which are listed on Exhibit 21.0
to the Company's Annual Report on Form 10-K for the fiscal year ended August 25,
2001 (each a "Subsidiary" and collectively the "Subsidiaries"), taken as a whole
(a "Material Adverse Effect"). Each Subsidiary is a direct or indirect
wholly-owned subsidiary of the Company. Each Subsidiary is duly incorporated,
validly existing and in good standing under the laws of its jurisdiction of
incorporation and is qualified to do business as a foreign corporation in each
jurisdiction in which qualification is required, except where failure to so
qualify would not have a Material Adverse Effect.


                                       -2-

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                  4.2 Authorized Capital Stock. As of February 23, 2002, the
authorized capital stock of the Company consists of (a) 50,000,000 shares of
Common Stock, of which 26,163,959 shares are issued and outstanding and
4,034,677 are reserved for issuance under the Company's stock option and
purchase plans; (b) 10,000,000 shares of preferred stock, no par value, 300,000
shares of which have been designated as Series A Junior Participating Preferred
Stock, none of which are issued or outstanding. The issued and outstanding
shares of the Company's Common Stock have been duly authorized and validly
issued, are fully paid and nonassessable, have been issued in compliance with
all federal and state securities laws and were not issued in violation of or
subject to any preemptive rights or other rights to subscribe for or purchase
securities, and conform in all material respects to the description thereof
contained in the Private Placement Memorandum. Except for stock options and
other awards granted under the option, award and purchase plans of the Company
described in the Private Placement Memorandum (as defined herein) or except as
disclosed in or contemplated by the Confidential Private Placement Memorandum
dated March 20, 2002 prepared by the Company, including all exhibits thereto
(except Exhibit E) and supplements and amendments thereto (the "Private
Placement Memorandum"), the Company does not have outstanding any options to
purchase, or any preemptive rights or other rights to subscribe for or to
purchase, any securities or obligations convertible into, or any contracts or
commitments to issue or sell, shares of its capital stock or any such options,
rights, convertible securities or obligations. The description of the Company's
stock, stock bonus and other stock plans or arrangements and the options or
other rights granted and exercised thereunder, set forth in the Private
Placement Memorandum accurately and fairly presents all material information
with respect to such plans, arrangements, options and rights, except that since
the date of the Private Placement Memorandum the Company has entered into an
amendment to the Rights Agreement dated May 22, 1997, by and between the Company
and Harris Trust and Savings Bank as Rights Agent. With respect to each
Subsidiary, (i) the Company owns, directly or indirectly, 100% of the
Subsidiary's capital stock (except for directors' qualifying shares), (ii) all
the issued and outstanding shares of the Subsidiary's capital stock have been
duly authorized and validly issued, are fully paid and nonassessable, have been
issued in compliance with applicable federal and state securities laws, were not
issued in violation of or subject to any preemptive rights or other rights to
subscribe for or purchase securities, and (iii) there are no outstanding options
to purchase, or any preemptive rights or other rights to subscribe for or to
purchase, any securities or obligations convertible into, or any contracts or
commitments to issue or sell, shares of the Subsidiary's capital stock or any
such options, rights, convertible securities or obligations.

                  4.3 Issuance, Sale and Delivery of the Shares. The Shares have
been duly authorized and, when issued, delivered and paid for in the manner set
forth in this Agreement, will be duly authorized, validly issued, fully paid and
nonassessable. No preemptive rights or other rights to subscribe for or purchase
exist with respect to the issuance and sale of the Shares by the Company
pursuant to this Agreement. No stockholder of the Company has any right (which
has not been waived or has not expired by reason of lapse of time following
notification of the Company's intent to file the registration statement to be
filed by it pursuant to Section 7.1 (the "Registration Statement")) to require
the Company to register the sale of any shares owned by such stockholder under
the Securities Act of 1933, as amended (the "Securities Act"), in the


                                       -3-

<PAGE>

Registration Statement. No further approval or authority of the stockholders or
the Board of Directors of the Company will be required for the issuance and sale
of the Shares to be sold by the Company as contemplated herein.

                  4.4 Due Execution, Delivery and Performance of this Agreement.
The Company has full legal right, corporate power and authority to enter into
this Agreement and perform the transactions contemplated hereby. This Agreement
has been duly authorized, executed and delivered by the Company. The execution,
delivery and performance of this Agreement by the Company and the consummation
of the transactions herein contemplated will not violate any provision of the
organizational documents of the Company and will not result in the creation of
any lien, charge, security interest or encumbrance upon any assets of the
Company or of any of its Subsidiaries pursuant to the terms or provisions of, or
will not conflict with, result in the breach or violation of, or constitute,
either by itself or upon notice or the passage of time or both, a default under
any agreement, mortgage, deed of trust, lease, franchise, license, indenture,
permit or other instrument to which the Company or any of its Subsidiaries is a
party or by which the Company or any of its Subsidiaries or any of their
respective properties may be bound or affected and in each case which would have
a Material Adverse Effect or, to the Company's knowledge, any statute or any
authorization, judgment, decree, order, rule or regulation of any court or any
regulatory body, administrative agency or other governmental body applicable to
the Company or any of its Subsidiaries or any of their respective properties
where such conflict, breach, violation or default is likely to result in a
Material Adverse Effect. No consent, approval, authorization or other order of
any court, regulatory body, administrative agency or other governmental body is
required for the execution and delivery of this Agreement or the consummation of
the transactions contemplated by this Agreement, except for compliance with the
Blue Sky laws and federal securities laws applicable to the offering of the
Shares. Upon the execution and delivery of this Agreement, and assuming the
valid execution thereof by the Purchaser, this Agreement will constitute a valid
and binding obligation of the Company, enforceable in accordance with its terms,
except as enforceability may be limited by applicable bankruptcy, insolvency,
reorganization, moratorium or similar laws affecting creditors' and contracting
parties' rights generally and except as enforceability may be subject to general
principles of equity (regardless of whether such enforceability is considered in
a proceeding in equity or at law) and except as the indemnification agreements
of the Company in Section 7.3 hereof may be legally unenforceable.

                  4.5 Accountants. The firm of KPMG LLP, which has expressed its
opinion with respect to the consolidated financial statements to be included in
the Registration Statement and the Prospectus which forms a part thereof, has
represented to the Company that KPMG LLP is an independent accountant as
required by the Securities Act and the rules and regulations promulgated
thereunder (the "Rules and Regulations").

                  4.6 No Defaults. Except as disclosed in the Private Placement
Memorandum, neither the Company nor any of its Subsidiaries is in violation or
default of any provision of its articles of incorporation or bylaws, or in
breach of or default with respect to any provision of any agreement, judgment,
decree, order, mortgage, deed of trust, lease, franchise, license, indenture,
permit or other instrument to which it is a party or by which it or any of its
properties are bound

                                      -4-



<PAGE>

and where such breach or default is reasonably likely to result in a Material
Adverse Effect; and there does not exist any state of fact which, with notice or
lapse of time or both, would constitute an event of default on the part of the
Company or any of its Subsidiaries as defined in such documents and which would
have a Material Adverse Effect.

                  4.7. Contracts. The contracts described in the Private
Placement Memorandum that are material to the Company are in full force and
effect on the date hereof; and neither the Company nor any of its Subsidiaries
nor, to the Company's knowledge, any other party thereto, is in breach of or
default under any of such contracts which breach or default would have a
Material Adverse Effect.

                  4.8 No Actions. Except as disclosed in the Private Placement
Memorandum, (1) there are no legal or governmental actions, suits, proceedings,
pending and (2) to the Company's knowledge, there are no inquiries or
investigations, nor are there any legal or governmental actions, suits, or
proceedings threatened, to which the Company or any of its Subsidiaries is or
may be a party or subject or of which property owned or leased by the Company or
any of its Subsidiaries is or may be the subject, or related to environmental or
discrimination matters, or instituted by the Commission, the National
Association of Securities Dealers, Inc., any state securities commission or
other governmental or regulatory entity, which actions, suits or proceedings,
individually or in the aggregate, might prevent or might reasonably be expected
to prevent or materially and adversely affect the transactions contemplated by
this Agreement or result in a Material Adverse Effect; and, to the Company's
knowledge, no labor disturbance by the employees of the Company or of any of its
Subsidiaries exists, or is imminent which is reasonably expected to have a
Material Adverse Effect. Except as disclosed in the Private Placement
Memorandum, neither the Company nor any of its Subsidiaries is party to or
subject to the provisions of any material injunction, judgment, decree or order
of any court, regulatory body administrative agency or other governmental body.

                  4.9 Properties. Each of the Company and its Subsidiaries has
good and marketable title to all the properties and assets reflected as owned by
it in the consolidated financial statements included in the Private Placement
Memorandum, subject to no lien, mortgage, pledge, charge or encumbrance of any
kind except (i) those, if any, reflected in such consolidated financial
statements, or (ii) those which are not material in amount and do not adversely
affect the use made and intended to be made of such property by the Company or
any of its Subsidiaries. Each of the Company and its Subsidiaries owns or leases
all such properties as are necessary to its operations as now conducted. Each of
the Company and its Subsidiaries holds its leased properties under valid and
binding leases, with such exceptions as are not materially significant in
relation to its business.

                  4.10 No Material Change. Since August 25, 2001 and except as
described in or specifically contemplated by the Private Placement Memorandum:
(i) neither the Company nor any of its Subsidiaries has incurred any material
liabilities or obligations, indirect, or contingent, or entered into any
material verbal or written agreement or other transaction not in the ordinary
course of business or which could reasonably be expected to have a Material
Adverse Effect; (ii) neither the Company nor any of its Subsidiaries has
sustained any material loss or interference

                                       -5-


<PAGE>

with its businesses or properties from fire, flood, windstorm, accident or other
calamity not covered by insurance; (iii) neither the Company nor any of its
Subsidiaries has paid or declared any dividends or other distributions with
respect to its capital stock and neither the Company nor any of its Subsidiaries
is in default in the payment of principal or interest on any outstanding debt
obligations; (iv) there has not been any change in the capital stock of the
Company or of any of its Subsidiaries other than the sale of the Shares
hereunder and shares or options issued pursuant to employee equity incentive
plans or purchase plans approved by the Company's Board of Directors and
repurchases of shares or options pursuant to repurchase plans already approved
by the Company's Board of Directors, or any increase in indebtedness material to
the Company or any of its Subsidiaries; and (v) there has not been any other
event or change that would have a Material Adverse Effect.

                  4.11 Intellectual Property. Except as disclosed in the Private
Placement Memorandum: (i) the Company owns or has obtained valid and enforceable
licenses or options for the inventions, patent applications, patents, trademarks
(both registered and unregistered), trade names, copyrights and trade secrets
necessary for the conduct of the Company's business as currently conducted
(collectively, the "Intellectual Property"); and (ii) (a) there are no third
parties who have any ownership rights to any Intellectual Property that is owned
by, or has been licensed to, the Company for the products described in the
Private Placement Memorandum that would preclude the Company from conducting its
business as currently conducted and have a Material Adverse Effect, except for
the ownership rights of the owners of the Intellectual Property licensed or
optioned by the Company; (b) to the Company's knowledge, there are currently no
sales of any products that would constitute an infringement by third parties of
any Intellectual Property owned, licensed or optioned by the Company, which
infringement would have a Material Adverse Effect; (c) there is no pending or,
to the Company's knowledge, threatened action, suit, proceeding or claim by
others challenging the rights of the Company in or to any Intellectual Property
owned, licensed or optioned by the Company, other than claims which would not
reasonably be expected to have a Material Adverse Effect; (d) there is no
pending or, to the Company's knowledge, threatened action, suit, proceeding or
claim by others challenging the validity or scope of any Intellectual Property
owned, licensed or optioned by the Company, other than non-material actions,
suits, proceedings and claims; and (e) there is no pending or, to the Company's
knowledge, threatened action, suit, proceeding or claim by others that the
Company infringes or otherwise violates any patent, trademark, copyright, trade
secret or other proprietary right of others, other than non-material actions,
suits, proceedings and claims.

                  4.12 Compliance. Neither the Company nor any of its
Subsidiaries has been advised, nor has reason to believe, that it is not
conducting business in compliance with all applicable laws, rules and
regulations of the jurisdictions in which it is conducting its business,
including, without limitation, all applicable local, state and federal
environmental laws and regulations; in each case, except where failure to be in
compliance would not have a Material Adverse Effect.

                  4.13 Taxes. Each of the Company and its Subsidiaries has filed
all necessary federal, state and foreign income and franchise tax returns and
has paid or accrued all taxes shown as due thereon, and neither the Company nor
any of its Subsidiaries has knowledge of a

                                       -6-


<PAGE>

tax deficiency which has been or might be asserted or threatened against it
which is reasonably likely to have a Material Adverse Effect.

                  4.14 Transfer Taxes. On the Closing Date, all stock transfer
or other taxes (other than income taxes) which are required to be paid in
connection with the sale and transfer of the Shares to be sold to the Purchaser
hereunder will be, or will have been, fully paid or provided for by the Company
and all laws imposing such taxes will be or will have been complied with.

                  4.15 Investment Company. The Company is not an "investment
company" or an "affiliated person" of, or "promoter" or "principal underwriter"
for an investment company, within the meaning of the Investment Company Act of
1940, as amended.

                  4.16 Offering Materials. The Company has not distributed and
will not distribute prior to the Closing Date any offering material in
connection with the offering and sale of the Shares other than the Private
Placement Memorandum or any amendment or supplement thereto. Neither the Company
nor any person acting on its behalf has in the past or will hereafter take any
action independent of the Placement Agents to sell, offer for sale or solicit
offers to buy any securities of the Company which would subject the offer,
issuance or sale of the Shares, as contemplated by this Agreement, to the
registration requirements of Section 5 of the Securities Act.

                  4.17 Insurance. The Company maintains insurance of the types
and in the amounts that the Company reasonably believes is adequate for its
business, including, but not limited to, insurance covering all real and
personal property owned or leased by the Company against theft, damage,
destruction, acts of vandalism and all other risks customarily insured against
by similarly situated companies, all of which insurance is in full force and
effect.

                  4.18 Contributions. The Company has not at any time since its
incorporation, directly or indirectly, (i) made any unlawful contribution to any
candidate for public office, or failed to disclose fully any contribution in
violation of law, or (ii) made any payment to any federal or state governmental
officer or official, or other person charged with similar public or quasi-public
duties, other than payments required or permitted by the laws of the United
States or any jurisdiction thereof.

                  4.19 Additional Information. The information contained in the
following documents, which the Placement Agents have furnished to the Purchaser,
or will furnish prior to the Closing, does not include any untrue statement of a
material fact or omit to state any material fact required to be stated therein
or necessary to make the statements therein, in the light of the circumstances
in which they were made, not misleading, as of their respective filing dates or,
if amended, as so amended:

                  (a)      the Company's Annual Report on Form 10-K for the year
                           ended August 25, 2001;



                                       -7-

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                  (b)      the Company's Quarterly Report on Form 10-Q for the
                           quarter ended November 24, 2001;

                  (c)      the Company's Current Report on Form 8-K filed with
                           the Commission on January 24, 2002;

                  (d)      the Company's Quarterly Report on Form 10-Q for the
                           quarter ended February 23, 2002; and

                  (e)      all other documents, if any, filed by the Company
                           with the Securities and Exchange Commission (the
                           "Commission") since August 25, 2001 pursuant to the
                           reporting requirements of the Securities Exchange Act
                           of 1934, as amended (the "Exchange Act").

In addition, as of the date of this Agreement, the Private Placement Memorandum
(including the exhibits thereto), which the Placement Agents have furnished to
the Purchaser, or will furnish prior to the Closing, when read together with the
information, qualifications and exceptions contained in this Agreement, does not
include any untrue statement of a material fact or omit to state any material
fact necessary to make the statements therein, in the light of the circumstances
in which they were made, not misleading.

                  4.20 Legal Opinion. Prior to the Closing, Faegre & Benson LLP,
counsel to the Company, will deliver its legal opinion to the Placement Agents
substantially in the form attached as Exhibit A to this agreement. Such opinion
shall also state that each of the Purchasers may rely thereon as though it were
addressed directly to such Purchaser.

                  4.21 Certificate. At the Closing, the Company will deliver to
the Purchaser a certificate executed by the chief executive officer, or the
chief financial or accounting officer of the Company, dated the Closing Date, in
form and substance reasonably satisfactory to the Purchaser, to the effect that
the representations and warranties of the Company set forth in this Section 4
are true and correct as of the date of this Agreement and as of the Closing
Date, and the Company has complied in all material respects with all the
agreements and satisfied all the conditions herein on its part to be performed
or satisfied on or prior to such Closing Date.

                  4.22 Price of Common Stock. The Company has not taken, and
will not take, directly or indirectly, any action designed to cause or result
in, or which has constituted or which might reasonably be expected to
constitute, the stabilization or manipulation of the price of the shares of the
Common Stock to facilitate the sale or resale of the Shares.

                  4.23 Reporting Company; Form S-3. The Company is subject to
the reporting requirements of the Exchange Act, has a class of securities
registered under Section 12 of the Exchange Act, and has filed all reports
required thereby. The Company is eligible to register the Shares for resale by
the Purchaser on a registration statement on Form S-3 under the Securities Act.
There exist no facts or circumstances (including without limitation any required
approvals or waivers or any circumstances that may delay or prevent the
obtaining of accountant's


                                       -8-




<PAGE>

consents) that reasonably could be expected to prohibit or delay the preparation
and filing of a registration statement on Form S-3 that will be available for
the resale of the Shares by the Purchaser.

                  4.24 Use of Proceeds. The Company shall use the proceeds from
the sale of Shares as described under "Use of Proceeds" in the Private Placement
Memorandum.

                  4.25 Quotation on Nasdaq. The Company shall use its
commercially reasonable efforts to maintain the designation and quotation, or
listing, of the Common Stock on the Nasdaq National Market System or on another
national securities exchange for a minimum of two (2) years following the
Closing Date.

                  4.26 Use of Purchaser Name. Except as may be required by
applicable law, the Company shall not use, directly or indirectly, the
Purchaser's name or the name of any of its affiliates in any advertisement,
announcement, press release or other similar communication unless it has
received the prior written consent of the Purchaser for the specific use
contemplated or as otherwise required by applicable law or regulation.

                  4.27 Non-Public Information. The Company has not disclosed to
the Purchaser, whether in the Private Placement Memorandum or otherwise,
information that would constitute material non-public information as of the
Closing Date.

                  SECTION 5. Representations, Warranties and Covenants of the
Purchaser. (a) The Purchaser represents and warrants to, and covenants with, the
Company that: (i) the Purchaser is knowledgeable, sophisticated and experienced
in making, and is qualified to make, decisions with respect to investments in
shares representing an investment decision like that involved in the purchase of
the Shares, including investments in securities issued by the Company and
comparable entities, and has requested, received, reviewed and considered all
information it deems relevant in making an informed decision to purchase the
Shares; (ii) the Purchaser is acquiring the number of Shares set forth in
Section 2 above in the ordinary course of its business and for its own account
for investment only and with no present intention of distributing any of such
Shares, and no arrangement or understanding exists with any other persons
regarding the distribution of such Shares (this representation and warranty not
limiting the Purchaser's right to sell such Shares pursuant to the Registration
Statement or in compliance with the Securities Act and the Rules and
Regulations, or, other than with respect to any claims arising out of a breach
of this representation and warranty, the Purchaser's right to indemnification
under Section 7.3); (iii) the Purchaser will not, directly or indirectly, offer,
sell, pledge, transfer or otherwise dispose of (or solicit any offers to buy,
purchase or otherwise acquire or take a pledge of) any of the Shares, nor will
Purchaser engage in any short sale which results in a disposition of any of the
Shares by Purchaser, except in compliance with the Securities Act, the Rules and
Regulations and such other securities or Blue Sky laws as may be applicable;
(iv) the Purchaser has completed or caused to be completed the Registration
Statement Questionnaire attached hereto as part of Appendix I, for use in
preparation of the Registration Statement, and the answers thereto are true and
correct as of the date hereof and will be true and correct as of the effective
date of the Registration Statement, and the Purchaser will

                                       -9-



<PAGE>

notify the Company immediately of any material change in any such information
provided in the Registration Statement Questionnaire; (v) the Purchaser has, in
connection with its decision to purchase the number of Shares set forth in
Section 2 above, relied solely upon the Private Placement Memorandum and the
documents included therein or incorporated by reference and the representations
and warranties of the Company contained herein; (vi) the Purchaser is an
"accredited investor" within the meaning of Rule 501(a) of Regulation D
promulgated under the Securities Act; and (vii) the Purchaser agrees to notify
the Company immediately of any change in any of the foregoing information until
such time as the Purchaser has sold all of its Shares or the Company is no
longer required to keep the Registration Statement effective.

                  (b) The Purchaser understands that the Shares are being
offered and sold to it in reliance upon specific exemptions from the
registration requirements of Securities Act, the Rules and Regulations and state
securities laws, and that the Company is relying upon the truth and accuracy of,
and the Purchaser's compliance with, the representations, warranties,
agreements, acknowledgments and understandings of the Purchaser set forth herein
in order to determine the availability of such exemptions and the eligibility of
the Purchaser to acquire the Shares.

(c) For the benefit of the Company, the Purchaser previously agreed orally with
the Placement Agents to keep confidential all information concerning this
private placement. The Purchaser understands that the information contained in
the Private Placement Memorandum is strictly confidential and proprietary to the
Company and has been prepared from the Company's publicly available documents
and other information and is being submitted to the Purchaser solely for such
Purchaser's confidential use. The Purchaser agrees to use the information
contained in the Private Placement Memorandum for the sole purpose of evaluating
a possible investment in the Shares and the Purchaser hereby acknowledges that
it is prohibited from reproducing or distributing the Private Placement
Memorandum, this Purchase Agreement, or any other offering materials or other
information provided by the Company in connection with the Purchaser's
consideration of its investment in the Company, in whole or in part, or
divulging or discussing any of their contents. Further, the Purchaser
understands that the existence and nature of all conversations and
presentations, if any, regarding the Company and this offering must be kept
strictly confidential. The Purchaser understands that the federal securities
laws impose restrictions on trading based on information regarding this
offering. In addition, the Purchaser hereby acknowledges that unauthorized
disclosure of information regarding this offering may cause the Company to
violate Regulation FD. In addition to the above, the Purchaser shall maintain in
confidence the receipt and content of any notice of a Suspension (as defined in
Section 5(h) below). The foregoing agreements shall not apply to any information
that is or becomes publicly available through no fault of the Purchaser, or that
the Purchaser is legally required to disclose; provided, however, that if the
Purchaser is requested or ordered to disclose any such information pursuant to
any court or other government order or any other applicable legal procedure, it
shall provide the Company with prompt notice of any such request or order in
time sufficient to enable the Company to seek an appropriate protective order.

                  (d) The Purchaser understands that its investment in the
Shares involves a significant degree of risk and that the market price of the
Common Stock has been and continues

                                      -10-


<PAGE>

to be volatile and that no representation is being made as to the future value
of the Common Stock. The Purchaser has the knowledge and experience in financial
and business matters as to be capable of evaluating the merits and risks of an
investment in the Shares and has the ability to bear the economic risks of an
investment in the Shares. The Purchaser has been afforded the opportunity to ask
questions of the Company regarding such matters.

                  (e) The Purchaser understands that no United States federal or
state agency or any other government or governmental agency has passed upon or
made any recommendation or endorsement of the Shares.

                  (f) The Purchaser understands that, until such time as the
Registration Statement has been declared effective or the Shares may be sold by
non-affiliates of the Company pursuant to Rule 144 under the Securities Act
without any restriction as to the number of securities as of a particular date
that can then be immediately sold, the Shares may bear a restrictive legend in
substantially the following form (and a stop-transfer order may be placed
against transfer of the certificates for the Shares):

                  "THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
                  REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED. THE
                  SECURITIES MAY NOT BE SOLD, TRANSFERRED OR ASSIGNED IN THE
                  ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT FOR THE
                  SECURITIES UNDER SAID ACT, OR AN OPINION OF COUNSEL, IN FORM,
                  SUBSTANCE AND SCOPE REASONABLY ACCEPTABLE TO THE COMPANY, THAT
                  REGISTRATION IS NOT REQUIRED UNDER SAID ACT OR UNLESS SOLD
                  PURSUANT TO RULE 144 UNDER SAID ACT."

                  (g) The Purchaser's principal executive offices are in the
jurisdiction set forth immediately below the Purchaser's name on the signature
pages hereto.

                  (h) The Purchaser hereby covenants with the Company not to
make any sale of the Shares under the Registration Statement without effectively
causing the prospectus delivery requirement under the Securities Act to be
satisfied, and the Purchaser acknowledges and agrees that such Shares are not
transferable on the books of the Company unless the certificate submitted to the
transfer agent evidencing the Shares is accompanied by a separate Purchaser's
Certificate of Subsequent Sale (i) in the form of Appendix II hereto, (ii)
executed by an officer of, or other authorized person designated by, the
Purchaser, and (iii) to the effect that (A) the Shares have been sold in
accordance with the Registration Statement, the Securities Act and any
applicable state securities or Blue Sky laws and (B) if applicable, the
requirement of delivering a current prospectus has been satisfied. The Purchaser
acknowledges that there may occasionally be times when the Company must suspend
the use of the prospectus forming a part of the Registration Statement (a
"Suspension") until such time as an amendment to the Registration Statement has
been filed by the Company and declared effective by the Commission, or such time
as such prospectus has been supplemented, or until such time as the Company has
filed an appropriate report with the Commission pursuant to the Exchange Act.
The Purchaser hereby covenants that it will not sell any Shares pursuant to said
prospectus

                                      -11-
<PAGE>


during the period commencing at the time at which the Company gives the
Purchaser written notice of the Suspension of the use of said prospectus and
ending at the time the Company gives the Purchaser written notice that the
Purchaser may thereafter effect sales pursuant to said prospectus. The Purchaser
shall not be prohibited from selling Shares under the Registration Statement as
a result of Suspensions on more than two occasions of not more than 30 days each
in any twelve-month period, unless, in the good faith judgment of the Company's
Board of Directors, upon advice of counsel, the sale of Shares under the
Registration Statement in reliance on this paragraph would be reasonably likely
to cause a violation of the Securities Act or the Exchange Act.

                  (i) The Purchaser further represents and warrants to, and
covenants with, the Company that (i) the Purchaser has full right, power,
authority and capacity to enter into this Agreement and to consummate the
transactions contemplated hereby and has taken all necessary action to authorize
the execution, delivery and performance of this Agreement, and (ii) upon the
execution and delivery of this Agreement, this Agreement shall constitute a
legal, valid and binding obligation of the Purchaser, enforceable in accordance
with its terms, except as enforceability may be limited by applicable
bankruptcy, insolvency, reorganization, moratorium or similar laws affecting
creditors' and contracting parties' rights generally and except as
enforceability may be subject to general principles of equity (regardless of
whether such enforceability is considered in a proceeding in equity or at law)
and except as the indemnification agreements of the Purchaser in Section 7.3
hereof may be legally unenforceable.

                  SECTION 6. Survival of Representations, Warranties and
Agreements. Notwithstanding any investigation made by any party to this
Agreement or by the Placement Agent, all covenants, agreements, representations
and warranties made by the Company and the Purchaser herein and in the
certificates for the Shares delivered pursuant hereto shall survive the
execution of this Agreement, the delivery to the Purchaser of the Shares being
purchased and the payment therefor.

                  SECTION 7. Registration of the Shares; Compliance with the
Securities Act.

                  7.1 Registration Procedures and Expenses. The Company shall:

                  (a) as soon as reasonably practicable, but in no event later
than ten days following the Closing Date, prepare and file with the Commission
the Registration Statement on Form S-3 relating to the sale of the Shares by the
Purchaser and the Other Purchasers from time to time on the Nasdaq National
Market or the facilities of any national securities exchange on which the Common
Stock is then traded or in privately-negotiated transactions;

                  (b) use its best efforts, subject to receipt of necessary
information from the Purchasers, to cause the Commission to declare the
Registration Statement effective within 60 days after the Closing Date;





                                      -12-

<PAGE>


                  (c) use its best efforts to promptly prepare and file with the
Commission such amendments and supplements to the Registration Statement and the
prospectus used in connection therewith as may be necessary to keep the
Registration Statement effective until the earliest of (i) two years after the
effective date of the Registration Statement, or (ii) such time as the Shares
become eligible for resale by non-affiliates pursuant to Rule 144(k) under the
Securities Act of 1933, as amended;

                  (d) furnish to the Purchaser with respect to the Shares
registered under the Registration Statement (and to each underwriter, if any, of
such Shares) such number of copies of prospectuses and such other documents as
the Purchaser may reasonably request, in order to facilitate the public sale or
other disposition of all or any of the Shares by the Purchaser;

                  (e) file documents required of the Company for normal Blue Sky
clearance in states specified in writing by the Purchaser; provided, however,
that the Company shall not be required to qualify to do business or consent to
service of process in any jurisdiction in which it is not now so qualified or
has not so consented;

                  (f) bear all expenses in connection with the procedures in
paragraphs (a) through (e) of this Section 7.1 and the registration of the
Shares pursuant to the Registration Statement, other than fees and expenses, if
any, of counsel or other advisers to the Purchaser or the Other Purchasers or
underwriting discounts, brokerage fees and commissions incurred by the Purchaser
or the Other Purchasers, if any;

                  (g) file a Form D with respect to the Shares as required under
Regulation D and to provide a copy thereof to the Purchaser promptly after
filing;

                  (h) issue a press release describing the transactions
contemplated by this Agreement on the Closing Date; and

                  (i) make available, while the Registration Statement is
effective and available for resale, its Chief Executive Officer, Chief Financial
Officer, and Executive Vice President--Business Development for questions
regarding information which the Purchaser may reasonably request in order to
fulfill any due diligence obligation on its part.

                  The Company understands that the Purchaser disclaims being an
underwriter, but the Purchaser being deemed an underwriter shall not relieve the
Company of any obligations it has hereunder. A draft of the proposed form of the
Registration Statement is included in the Private Placement Memorandum and a
questionnaire related thereto to be completed by the Purchaser is attached
hereto as Appendix I.

                  7.2 Transfer of Shares After Registration. While the
Registration Statement is effective and available for resale, the Purchaser
agrees that it will not effect any disposition of the Shares or its right to
purchase the Shares that would constitute a sale within the meaning of the
Securities Act, except as contemplated in the Registration Statement referred to
in Section 7.1 hereof in the section titled "Plan of Distribution," and that it
will promptly notify the


                                      -13-


<PAGE>

Company of any changes in the information set forth in the Registration
Statement regarding the Purchaser or its plan of distribution.

                  7.3  Indemnification.  For the purpose of this Section 7.3:

                  (i)      the term "Purchaser/Affiliate" shall mean any
                           affiliates of the Purchaser and any person who
                           controls the Purchaser or any affiliate of the
                           Purchaser within the meaning of Section 15 of the
                           Securities Act or Section 20 of the Exchange Act; and

                  (ii)     the term "Registration Statement" shall include any
                           final prospectus, exhibit, supplement or amendment
                           included in or relating to, and any document
                           incorporated by reference in, the Registration
                           Statement referred to in Section 7.1 hereof.

                  (a) The Company agrees to indemnify and hold harmless the
Purchaser and the Purchaser/Affiliate against any losses, claims, damages,
liabilities or expenses, joint or several, to which the Purchaser or
Purchaser/Affiliate may become subject, under the Securities Act, the Exchange
Act, or any other federal or state statutory law or regulation, or at common law
or otherwise (including in settlement of any litigation, if such settlement is
effected with the written consent of the Company), insofar as such losses,
claims, damages, liabilities or expenses (or actions in respect thereof as
contemplated below) arise out of or are based upon any untrue statement or
alleged untrue statement of any material fact contained in the Registration
Statement, including the prospectus, financial statements and schedules, and all
other documents filed as a part thereof, as amended at the time of effectiveness
of the Registration Statement, including any information deemed to be a part
thereof as of the time of effectiveness pursuant to paragraph (b) of Rule 430A,
or pursuant to Rule 434, of the Rules and Regulations, or the prospectus, in the
form first filed with the Commission pursuant to Rule 424(b) of the Regulations,
or filed as part of the Registration Statement at the time of effectiveness if
no Rule 424(b) filing is required (the "Prospectus"), or any amendment or
supplement thereto, or arise out of or are based upon the omission or alleged
omission to state in any of them a material fact required to be stated therein
or necessary to make the statements in the Registration Statement or any
amendment or supplement thereto not misleading or in the Prospectus or any
amendment or supplement thereto not misleading in the light of the circumstances
under which they were made, or arise out of or are based in whole or in part on
any inaccuracy in the representations and warranties of the Company contained in
this Agreement, or any failure of the Company to perform its obligations
hereunder or under law, and will reimburse the Purchaser or Purchaser/Affiliate
for any legal and other expenses as such expenses are reasonably incurred by the
Purchaser or Purchaser/Affiliate in connection with investigating, defending,
settling, compromising or paying any such loss, claim, damage, liability,
expense or action; provided, however, that the Company will not be liable in any
such case to the extent that any such loss, claim, damage, liability or expense
arises out of or is based upon (i) an untrue statement or alleged untrue
statement or omission or alleged omission made in the Registration Statement,
the Prospectus or any amendment or supplement thereto in reliance upon and in
conformity with written information furnished to the Company by or on behalf of
the Purchaser expressly for use

                                      -14-


<PAGE>

therein, or (ii) the failure of the Purchaser to comply with the covenants and
agreements contained in Sections 5(h) or 7.2 hereof respecting the sale of the
Shares, or (iii) the inaccuracy of any representations made by the Purchaser
herein or (iv) any statement or omission in any Prospectus that is corrected in
any subsequent Prospectus that was delivered to the Purchaser prior to the
pertinent sale or sales by the Purchaser.

                  (b) The Purchaser will severally, but not jointly, indemnify
and hold harmless the Company, each of its directors, each of its officers who
signed the Registration Statement and each person, if any, who controls the
Company within the meaning of Section 15 of the Securities Act or Section 20 of
the Exchange Act, against any losses, claims, damages, liabilities or expenses
to which the Company, each of its directors, each of its officers who signed the
Registration Statement or controlling person may become subject, under the
Securities Act, the Exchange Act, or any other federal or state statutory law or
regulation, or at common law or otherwise (including in settlement of any
litigation, if such settlement is effected with the written consent of the
Purchaser) insofar as such losses, claims, damages, liabilities or expenses (or
actions in respect thereof as contemplated below) arise out of or are based upon
(i) any failure to comply with the covenants and agreements contained in
Sections 5(h) or 7.2 hereof respecting the sale of the Shares or (ii) the
inaccuracy of any representation made by the Purchaser herein or (iii) any
untrue or alleged untrue statement of any material fact contained in the
Registration Statement, the Prospectus, or any amendment or supplement thereto,
or arise out of or are based upon the omission or alleged omission to state
therein a material fact required to be stated therein or necessary to make the
statements in the Registration Statement or any amendment or supplement thereto
not misleading or in the Prospectus or any amendment or supplement thereto not
misleading in the light of the circumstances under which they were made, in each
case to the extent, but only to the extent, that such untrue statement or
alleged untrue statement or omission or alleged omission was made in the
Registration Statement, the Prospectus, or any amendment or supplement thereto,
in reliance upon and in conformity with written information furnished to the
Company by the Purchaser expressly for use therein, and will reimburse the
Company, each of its directors, each of its officers who signed the Registration
Statement or controlling person for any legal and other expense reasonably
incurred by the Company, each of its directors, each of its officers who signed
the Registration Statement or controlling person in connection with
investigating, defending, settling, compromising or paying any such loss, claim,
damage, liability, expense or action.

                  (c) Promptly after receipt by an indemnified party under this
Section 7.3 of notice of the threat or commencement of any action, such
indemnified party will, if a claim in respect thereof is to be made against an
indemnifying party under this Section 7.3 promptly notify the indemnifying party
in writing thereof; but the omission so to notify the indemnifying party will
not relieve it from any liability which it may have to any indemnified party for
contribution or otherwise than under the indemnity agreement contained in this
Section 7.3 or to the extent it is not prejudiced as a result of such failure.
In case any such action is brought against any indemnified party and such
indemnified party seeks or intends to seek indemnity from an indemnifying party,
the indemnifying party will be entitled to participate in, and, to the extent
that it may wish, jointly with all other indemnifying parties similarly
notified, to assume


                                      -15-

<PAGE>

the defense thereof with counsel reasonably satisfactory to such indemnified
party; provided, however, if the defendants in any such action include both the
indemnified party, based upon the advice of such indemnified party's counsel,
and the indemnifying party and the indemnified party shall have reasonably
concluded that there may be a conflict of interest between the positions of the
indemnifying party and the indemnified party in conducting the defense of any
such action or that there may be legal defenses available to it and/or other
indemnified parties which are different from or additional to those available to
the indemnifying party, the indemnified party or parties shall have the right to
select separate counsel to assume such legal defenses and to otherwise
participate in the defense of such action on behalf of such indemnified party or
parties. Upon receipt of notice from the indemnifying party to such indemnified
party of its election so to assume the defense of such action and approval by
the indemnified party of counsel, the indemnifying party will not be liable to
such indemnified party under this Section 7.3 for any legal or other expenses
subsequently incurred by such indemnified party in connection with the defense
thereof unless (i) the indemnified party shall have employed such counsel in
connection with the assumption of legal defenses in accordance with the proviso
to the preceding sentence (it being understood, however, that the indemnifying
party shall not be liable for the expenses of more than one separate counsel,
approved by such indemnifying party in the case of paragraph (a), representing
the indemnified parties who are parties to such action (including indemnified
parties under other Purchase Agreements), plus local counsel, if appropriate) or
(ii) the indemnifying party shall not have employed counsel reasonably
satisfactory to the indemnified party to represent the indemnified party within
a reasonable time after notice of commencement of action, in each of which cases
the reasonable fees and expenses of counsel shall be at the expense of the
indemnifying party.

                  (d) If the indemnification provided for in this Section 7.3 is
required by its terms but is for any reason held to be unavailable to or
otherwise insufficient to hold harmless an indemnified party under paragraphs
(a), (b) or (c) of this Section 7.3 in respect to any losses, claims, damages,
liabilities or expenses referred to herein, then each applicable indemnifying
party shall contribute to the amount paid or payable by such indemnified party
as a result of any losses, claims, damages, liabilities or expenses referred to
herein (i) in such proportion as is appropriate to reflect the relative benefits
received by the Company and the Purchaser from the placement of the Common Stock
contemplated by this Agreement or (ii) if the allocation provided by clause (i)
above is not permitted by applicable law, in such proportion as is appropriate
to reflect not only the relative benefits referred to in clause (i) above but
the relative fault of the Company and the Purchaser in connection with the
statements or omissions or inaccuracies in the representations and warranties in
this Agreement that resulted in such losses, claims, damages, liabilities or
expenses, as well as any other relevant equitable considerations. The relative
benefits received by the Company on the one hand and the Purchaser on the other
shall be deemed to be in the same proportion as the amount paid by the Purchaser
to the Company pursuant to this Agreement for the Shares purchased by the
Purchaser that were sold pursuant to the Registration Statement bears to the
difference between the amount the Purchaser paid for the Shares that were sold
pursuant to the Registration Statement and the amount received by the Purchaser
from such sale. The relative fault of the Company on the one hand and the
Purchaser on the other shall be determined by reference to, among other things,
whether


                                      -16-


<PAGE>

the untrue or alleged statement of a material fact or the omission or alleged
omission to state a material fact or the inaccurate or the alleged inaccurate
representation and/or warranty relates to information supplied by the Company or
by the Purchaser and the parties' relative intent, knowledge, access to
information and opportunity to correct or prevent such statement or omission.
The amount paid or payable by a party as a result of the losses, claims,
damages, liabilities and expenses referred to above shall be deemed to include,
subject to the limitations set forth in paragraph (c) of this Section 7.3, any
legal or other fees or expenses reasonably incurred by such party in connection
with investigating or defending any action or claim. The provisions set forth in
paragraph (c) of this Section 7.3 with respect to the notice of the threat or
commencement of any threat or action shall apply if a claim for contribution is
to be made under this paragraph (d); provided, however, that no additional
notice shall be required with respect to any threat or action for which notice
has been given under paragraph (c) for purposes of indemnification. The Company
and the Purchaser agree that it would not be just and equitable if contribution
pursuant to this Section 7.3 were determined solely by pro rata allocation (even
if the Purchaser were treated as one entity for such purpose) or by any other
method of allocation which does not take account of the equitable considerations
referred to in this paragraph. Notwithstanding the provisions of this Section
7.3, the Purchaser shall not be required to contribute any amount in excess of
the amount the Purchaser paid to the Company pursuant to this Agreement for the
Shares purchased by the Purchaser that were sold pursuant to the Registration
Statement. No person guilty of fraudulent misrepresentation (within the meaning
of Section 11(f) of the Securities Act) shall be entitled to contribution from
any person who was not guilty of such fraudulent misrepresentation. The
Purchaser's obligation to contribute pursuant to this Section 7.3 is several and
not joint.

                  7.4 Termination of Conditions and Obligations. The conditions
precedent imposed by Section 5 or this Section 7 upon the transferability of the
Shares shall cease and terminate as to any particular number of the Shares upon
the passage of two years from the effective date of the Registration Statement
covering such Shares or at such time as an opinion of counsel satisfactory in
form and substance to the Company shall have been rendered to the effect that
such conditions are not necessary in order to comply with the Securities Act.

                  7.5 Information Available. So long as the Registration
Statement is effective covering the resale of Shares owned by the Purchaser, the
Company will furnish to the Purchaser:

                  (a) as soon as practicable after available (but in the case of
the Company's Annual Report to Stockholders, concurrently with delivery to its
shareholders generally) one copy of (i) its Annual Report to Stockholders (which
Annual Report shall contain financial statements audited in accordance with US
generally accepted accounting principles by a national firm of certified public
accountants), (ii) if not included in substance in the Annual Report to
Stockholders, upon the request of the Purchaser, its Annual Report on Form 10-K,
(iii) upon the request of the Purchaser, its Quarterly Reports on Form 10-Q,
(iv) upon the request of the Purchaser, its Current Reports on Form 8-K, and (v)
a full copy of the particular Registration Statement covering the Shares (the
foregoing, in each case, excluding exhibits);


                                      -17-

<PAGE>

                  (b) upon the request of the Purchaser, all exhibits excluded
by the parenthetical to subparagraph (a)(v) of this Section 7.5; and

                  (c) upon the request of the Purchaser, a reasonable number of
copies of the prospectuses to supply to any other party requiring such
prospectuses;

and the Company, upon the reasonable request of the Purchaser, will meet with
the Purchaser or a representative thereof at the Company's headquarters to
discuss information relevant for disclosure in the Registration Statement
covering the Shares.

                  SECTION 8. Broker's Fee. The Purchaser acknowledges that the
Company intends to pay to the Placement Agents a fee in respect of the sale of
the Shares to the Purchaser. Each of the parties hereto hereby represents that,
on the basis of any actions and agreements by it, there are no other brokers or
finders entitled to compensation in connection with the sale of the Shares to
the Purchaser.

                  SECTION 9. Notices. All notices, requests, consents and other
communications hereunder shall be in writing, shall be mailed by first-class
registered or certified airmail, confirmed facsimile or nationally recognized
overnight express courier postage prepaid, and shall be deemed given when so
mailed and shall be delivered as addressed as follows:

                  (a)      if to the Company, to:

                                FSI International, Inc.
                                3455 Lyman Boulevard
                                Chaska, Minnesota 55318-3052
                                Attention: Chief Financial Officer
                                Facsimile: (952) 448-1300

                           with a copy to:

                                Faegre & Benson LLP
                                2200 Wells Fargo Center
                                90 South Seventh Street
                                Minneapolis, MN 55402-3902
                                Attention: Douglas P. Long, Esq.
                                Facsimile: (612) 766-1600

                           or to such other person at such other place as the
                           Company shall designate to the Purchaser in writing;
                           and

                  (b)      if to the Purchaser, at its address as set forth at
                           the end of this Agreement, or at such other address
                           or addresses as may have been furnished to the
                           Company in writing.



                                      -18-

<PAGE>

                  SECTION 10. Changes. This Agreement may not be modified or
amended except pursuant to an instrument in writing signed by the Company and
the Purchaser.

                  SECTION 11. Headings. The headings of the various sections of
this Agreement have been inserted for convenience of reference only and shall
not be deemed to be part of this Agreement.

                  SECTION 12. Severability. In case any provision contained in
this Agreement should be invalid, illegal or unenforceable in any respect, the
validity, legality and enforceability of the remaining provisions contained
herein shall not in any way be affected or impaired thereby.

                  SECTION 13. Governing Law. This Agreement shall be governed by
and construed in accordance with the laws of the State of New York and the
federal law of the United States of America.

                  SECTION 14. Counterparts. This Agreement may be executed in
two or more counterparts, each of which shall constitute an original, but all of
which, when taken together, shall constitute but one instrument, and shall
become effective when one or more counterparts have been signed by each party
hereto and delivered to the other parties. Facsimile signatures shall be deemed
original signatures.

                  SECTION 15. Entire Agreement. This Agreement and the
instruments referenced herein contain the entire understanding of the parties
with respect to the matters covered herein and therein and, except as
specifically set forth herein or therein, neither the Company nor the Purchaser
makes any representation, warranty, covenant or undertaking with respect to such
matters.

                  SECTION 16. Third Party Beneficiaries. This Agreement is
intended for the benefit of the parties hereto and their respective permitted
successors and assigns, and is not for the benefit of, nor may any provision
hereof be enforced by, any other person.

                  SECTION 17. Assignment. This Agreement and the rights of the
Purchaser hereunder may not be assigned by Purchaser without the prior written
consent of the Company (except (x) by operation of law; (y) by the Purchaser to
its wholly owned subsidiary; or (z) by an investment advisor to a fund for which
it is the advisor or by or among funds that are under common control, provided
that such assignee agrees to be bound by the terms of this Agreement) and shall
be binding upon and shall inure to the benefit of the parties hereto and their
respective permitted successors, heirs and legal representatives.








                                      -19-

<PAGE>


                  IN WITNESS WHEREOF, the parties hereto have caused this
Agreement to be executed by their duly authorized representatives as of the day
and year first above written.


                                   FSI INTERNATIONAL, INC.



                                   By:
                                      ------------------------------------
                                      Name:
                                      Title:


Print or Type:
                                   Name of Purchaser
                                      (Individual or Institution):

                                   ---------------------------------------

                                   Name of Individual representing
                                      Purchaser (if an Institution):

                                   ---------------------------------------

                                   Title of Individual representing
                                      Purchaser (if an Institution):

                                   ---------------------------------------


Signature by:
                                   Individual Purchaser or Individual
                                      representing Purchaser:

                                   ---------------------------------------

                                   Address:
                                           -------------------------------

                                   Telephone:
                                             -----------------------------

                                   Facsimile:
                                             -----------------------------

<PAGE>

                       SUMMARY INSTRUCTION SHEET FOR PURCHASER

                   (to be read in conjunction with the entire
                        Purchase Agreement that follows)


A.       Complete the following items on BOTH Purchase Agreements (Please sign
         TWO originals):

         1.       Page 19 - Signature:

                  (i)      Name of Purchaser (Individual or Institution)

                  (ii)     Name of Individual representing Purchaser (if an
                           Institution)

                  (iii)    Title of Individual representing Purchaser (if an
                           Institution)

                  (iv)     Signature of Individual Purchaser or Individual
                           representing Purchaser

         2.       Appendix I - Stock Certificate Questionnaire:

                  Provide the information requested by the Stock Certificate
                  Questionnaire.

         3.       Return BOTH properly completed and signed Purchase Agreements
                  including the properly completed Appendix I to (initially by
                  facsimile with hard copy by overnight delivery):

                           Lehman Brothers Inc.
                           745 Seventh Avenue,
                            19th Floor
                           New York, NY 10019
                           Attention: Grant Miller

                           Facsimile: 646-758-3885

B.       Instructions regarding the transfer of funds for the purchase of Shares
         will be sent by facsimile to the Purchaser by the Placement Agents at a
         later date.

C.       Upon the resale of the Shares by the Purchaser after the Registration
         Statement covering the Shares is effective, as described in the
         Purchase Agreement, the Purchaser:

                  (i)      must deliver a current prospectus of the Company to
                           the buyer (prospectuses must be obtained from the
                           Company at the Purchaser's request); and

                  (ii)     must send a letter in the form of Appendix II to the
                           Company so that the Shares may be properly
                           transferred.
<PAGE>

                                                                      APPENDIX I


                             FSI INTERNATIONAL, INC.
                        STOCK CERTIFICATE QUESTIONNAIRE



         Pursuant to Section 3 of the Agreement, please provide us with the
following information:


1.       The exact name that your Shares are to be
         registered in (this is the name that will appear
         on your stock certificate(s)). You may use a
         nominee name if appropriate:
                                                              ------------------
2.       The relationship between the Purchaser of the
         Shares and the Registered Holder listed
         in response to item 1 above:
                                                              ------------------
3.       The mailing address of the Registered Holder
         listed in response to item 1 above:
                                                              ------------------

                                                              ------------------

                                                              ------------------

                                                              ------------------
4.       The Social Security Number or Tax
         Identification Number of the Registered
         Holder listed in response to item 1 above:
                                                              ------------------

<PAGE>

                             FSI INTERNATIONAL, INC.
                      REGISTRATION STATEMENT QUESTIONNAIRE


                  In connection with the preparation of the Registration
Statement, please provide us with the following information:

                  1. Pursuant to the "Selling Shareholder" section of the
Registration Statement, please state your or your organization's name exactly as
it should appear in the Registration Statement:

                  2. Please provide the number of shares that you or your
organization will beneficially own immediately after Closing, including those
Shares purchased by you or your organization pursuant to this Purchase Agreement
and those shares purchased by you or your organization through other
transactions:

                  3. Have you or your organization had any position, office or
other material relationship within the past three years with the Company or its
affiliates?


                                 Yes               No
                           -----             -----

       If yes, please indicate the nature of any such relationships below:

       -----------------------------------------------------------------

       -----------------------------------------------------------------

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                  4. Are you (i) an NASD Member (see definition), (ii) a
Controlling (see definition) shareholder of an NASD Member, (iii) a Person
Associated with a Member of the NASD (see definition), or (iv) an Underwriter or
a Related Person (see definition) with respect to the proposed offering; or (b)
do you own any shares or other securities of any NASD Member not purchased in
the open market; or (c) have you made any outstanding subordinated loans to any
NASD Member?

         Answer:  [   ] Yes    [   ] No    If "yes," please describe below

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<PAGE>

         NASD Member. The term "NASD member" means either any broker or dealer
admitted to membership in the National Association of Securities Dealers, Inc.
("NASD"). (NASD Manual, By-laws Article I, Definitions)

         Control. The term "control" (including the terms "controlling,"
"controlled by" and "under common control with") means the possession, direct or
indirect, of the power, either individually or with others, to direct or cause
the direction of the management and policies of a person, whether through the
ownership of voting securities, by contract, or otherwise. (Rule 405 under the
Securities Act of 1933, as amended)

         Person Associated with a member of the NASD. The term "person
associated with a member of the NASD" means every sole proprietor, partner,
officer, director, branch manager or executive representative of any NASD
Member, or any natural person occupying a similar status or performing similar
functions, or any natural person engaged in the investment banking or securities
business who is directly or indirectly controlling or controlled by a NASD
Member, whether or not such person is registered or exempt from registration
with the NASD pursuant to its bylaws. (NASD Manual, By-laws Article I,
Definitions)

         Underwriter or a Related Person. The term "underwriter or a related
person" means, with respect to a proposed offering, underwriters, underwriters'
counsel, financial consultants and advisors, finders, members of the selling or
distribution group, and any and all other persons associated with or related to
any of such persons. (NASD Interpretation)












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<PAGE>


                                                                     APPENDIX II

 Attention:

                   PURCHASER'S CERTIFICATE OF SUBSEQUENT SALE

         The undersigned, [an officer of, or other person duly authorized by]
            _____________________________________________________________

[fill in official name of individual or institution]
hereby certifies that he/she [said institution] is the Purchaser of
     the shares evidenced by the attached certificate, and as such,
sold such shares on __________________ in accordance with and in the manner
                          [date]
described in
Registration Statement number __________________________________________________
                                   [fill in the number of or otherwise identify

________________________________  and the requirement of delivering a
Registration Statement]
current prospectus by the Company has been complied with in connection with
such sale.


Print or Type:

          Name of Purchaser
            (Individual or
            Institution):      ______________________

          Name of Individual
            representing
            Purchaser (if an
            Institution)       ______________________

          Title of Individual
            representing
            Purchaser (if an
            Institution):      ______________________

Signature by:

          Individual Purchaser
            or Individual
            representing
            Purchaser:         ______________________


<PAGE>


                                    Exhibit A

                              Form of Legal Opinion


                  1. The Company is a corporation duly incorporated, validly
existing and in good standing under the laws of the State of Minnesota. Each
subsidiary of the Company organized in the United States has been duly
incorporated and is validly existing as a corporation in good standing under the
laws of its jurisdiction of formation. The Company and each of its subsidiaries
organized in the United States have all requisite corporate power and authority
to own, lease, license and operate its properties and assets and to conduct its
business as described in the Private Placement Memorandum.

                  2. The authorized capital stock of the Company conforms in all
material respects as to legal matters to the description thereof contained in
the Company's registration statement on Form 8-A.

                  3. The Shares have been duly authorized and, when issued and
delivered to the Investors against payment therefor in accordance with the terms
of the Purchase Agreements, will be validly issued, fully paid and nonassessable
and free of any preemptive or similar rights.

                  4. The form of the certificates for the Shares conforms to the
requirements of Minnesota Business Corporation Act.

                  5. The Company has full corporate power and authority to enter
into the Purchase Agreements and the Engagement Letter and to issue, sell and
deliver the Shares to the Investors as provided in the Purchase Agreements, and
the Purchase Agreements and the Engagement Letter have been duly authorized,
executed and delivered by the Company and are the legal, valid and binding
obligations of the Company, enforceable against the Company in accordance with
their terms.

                  6. The Company's execution, delivery and performance of the
Purchase Agreements and the Engagement Letter do not and will not (i) violate
the Articles of Incorporation or Bylaws of the Company or any of its
subsidiaries, (ii) violate, result in a breach of or constitute a default (alone
or with notice or passage of time or both) any agreement, indenture, lease or
other instrument to which the Company or any of its subsidiaries is a party or
by which any of them or any of their respective properties or assets is bound or
subject that is made an exhibit to the Company's Annual Report on Form 10-K for
the fiscal year ended August 25, 2001 (the "Form 10-K"), any Quarterly Report on
Form 10-Q or any Current Report on Form 8-K filed by the Company subsequent to
the filing of the Form 10-K, (iii) result in the creation or imposition of any
lien, charge, claim, security interest or encumbrance upon any property or
assets of the Company or any of its subsidiaries under such agreements,
indentures, leases and other instruments, or (iv) result in any violation of any
existing federal or Minnesota corporate law, regulation or ruling applicable to
the Company or any of its subsidiaries (assuming compliance with all applicable
state securities and Blue Sky laws, the Securities Act of 1933, as amended (the
"Securities Act"), and the Securities Exchange Act of 1934, as amended), or any


<PAGE>

judgment, injunction, order or decree known to us to be applicable to the
Company, any of its subsidiaries or any of their respective properties or
assets.

                  7. No consent, approval, authorization or order of, or
registration or filing with any federal, state or local governmental or
regulatory commission, board, body, authority or agency is required on the part
of the Company for the performance by the Company of its obligations at the
closing of the transactions contemplated by the Purchase Agreements, except as
may be required under the Securities Act or such as may be required under the
state securities or Blue Sky laws governing the purchase and distribution of the
Shares in connection with the purchase and sale of the Shares.

                  8. To our knowledge, there are no actions, suits,
arbitrations, claims, governmental or other proceedings or investigations
pending or threatened against the Company or any of its subsidiaries or any of
their respective operations, businesses, properties or assets which challenge
the validity of any actions taken or to be taken by the Company pursuant to the
Purchase Agreements, the Engagement Letter or the transactions contemplated
thereby.

                  9. To our knowledge, no holders of securities of the Company
have rights, which have not been waived or complied with, to the registration of
shares of Common Stock or other securities of the Company because of the filing
of the Resale Registration Statement or the offering contemplated thereby.

                  10. The Company is not, and after giving effect to the
offering and sale of the Shares will not be required to register as, an
"investment company" as such term is defined in the Investment Company Act of
1940, as amended.

                  11. Assuming the accuracy of the representations and
warranties of the Purchasers and the Company made in the Purchase Agreements,
and the compliance by the Placement Agent with the offering and solicitation
procedures outlined in its certificate attached hereto, the offer and sale of
the Shares is exempt from the registration requirements of the Act, subject to
the timely filing by the Company of a Form D pursuant to Regulation D
promulgated by the Securities and Exchange Commission under the Act.


















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