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                                                                     EXHIBIT 4.3

                                  $250,000,000

                                   CYMER, INC.

           3 1/2% CONVERTIBLE SUBORDINATED NOTES DUE FEBRUARY 15, 2009

                          REGISTRATION RIGHTS AGREEMENT

                                                               February 15, 2002

Credit Suisse First Boston Corporation
Merrill Lynch Pierce Fenner & Smith Incorporated
c/o Credit Suisse First Boston Corporation
    Eleven Madison Avenue
    New York, New York 10010-3629

Dear Sirs:

     Cymer, Inc., a Nevada corporation (the "COMPANY"), proposes to issue and
sell to Credit Suisse First Boston Corporation and Merrill Lynch Pierce Fenner &
Smith Incorporated (the "INITIAL PURCHASERS"), upon the terms set forth in a
purchase agreement dated February 12, 2002 (the "PURCHASE AGREEMENT"),
$250,000,000 aggregate principal amount of its 3 1/2% Convertible Subordinated
Notes due February 15, 2009 (the "INITIAL SECURITIES"). The Initial Securities
will be convertible into shares of common stock, par value $0.001 per share, of
the Company (together with any other shares of common stock as may constitute
"Common Stock" for purposes of the Indenture, the "COMMON STOCK") at the
conversion price set forth in the Offering Circular dated February 12, 2002 (the
"OFFERING CIRCULAR"). The Initial Securities will be issued pursuant to an
Indenture, dated as of February 15, 2002 (the "INDENTURE"), among the Company
and State Street Bank and Trust Company of California, N.A., as trustee (the
"TRUSTEE"). As an inducement to the Initial Purchasers to enter into the
Purchase Agreement, the Company agrees with the Initial Purchasers, for the
benefit of (i) the Initial Purchasers and (ii) the subsequent holders of the
Initial Securities and the Common Stock issuable upon conversion of the Initial
Securities (collectively, the "SECURITIES") (each of the foregoing a "HOLDER"
and collectively the "HOLDERS"), as follows:

     1. SHELF REGISTRATION. (a) The Company shall, at its cost, prepare and, as
promptly as practicable (but in no event more than 90 days after the first date
of original issuance of the Initial Securities) file with the Securities and
Exchange Commission (the "COMMISSION") and thereafter use commercially
reasonable efforts to cause to be declared effective as soon as practicable a
registration statement on Form S-3 or such other form as the Company may be
permitted to use (the "SHELF REGISTRATION STATEMENT") relating to the offer and
sale of the Transfer Restricted Securities (as defined in Section 5 hereof) by
the Holders thereof from time to time in accordance with the methods of
distribution set forth in the Shelf Registration Statement and Rule 415 under
the Securities Act of 1933, as amended (the "SECURITIES ACT") (hereinafter, the
"SHELF REGISTRATION"); PROVIDED, HOWEVER, that no Holder (other than the Initial
Purchasers) shall be entitled to have the Securities held by it covered by such
Shelf Registration Statement unless such Holder agrees in writing to be bound by
all the provisions of this Agreement applicable to such Holder.

     (b) The Company shall use commercially reasonable efforts to keep the Shelf
Registration Statement continuously effective in order to permit the prospectus
included therein (the "PROSPECTUS") to be

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lawfully delivered by the Holders of the relevant Securities, for a period of
two years (or for such longer period if extended pursuant to Section 2(h) below)
from the date of its effectiveness or such shorter period that will terminate
when all the Securities covered by the Shelf Registration Statement (i) have
been sold pursuant thereto or (ii) are no longer restricted securities (as
defined in Rule 144(k) under the Securities Act, or any successor rule thereof),
assuming for this purpose that the Holders thereof are not affiliates (as
defined in Rule 144(a)(1) under the Securities Act) of the Company (in any such
case, such period being called the "SHELF REGISTRATION PERIOD"). The Company
shall be deemed not to have used commercially reasonable efforts to keep the
Shelf Registration Statement effective during the requisite period if it
voluntarily takes any action that would result in Holders of Securities covered
thereby not being able to offer and sell such Securities during that period,
unless such action is (i) required by applicable law or (ii) taken by the
Company in good faith and contemplated by Section 2(b)(v) or Section 2(b)(vi)
below, and the Company thereafter complies with the requirements of Section
2(h).

     (c) Notwithstanding any other provisions of this Agreement to the contrary,
the Company shall cause the Shelf Registration Statement and the Prospectus and
any amendment or supplement thereto, as of the effective date of the Shelf
Registration Statement, amendment or supplement, (i) to comply in all material
respects with the applicable requirements of the Securities Act and the rules
and regulations of the Commission and (ii) not to contain any untrue statement
of a material fact or omit to state a material fact required to be stated
therein or necessary in order to make the statements therein, in light of the
circumstances under which they were made, not misleading.

     2. REGISTRATION PROCEDURES. In connection with the Shelf Registration
contemplated by Section 1 hereof, the following provisions shall apply:

     (a) The Company shall (i) furnish to the Initial Purchasers, prior to the
filing thereof with the Commission, a copy of the Shelf Registration Statement
and each amendment thereof and each supplement, if any, to the prospectus
included therein and, in the event that an Initial Purchaser (with respect to
any portion of an unsold allotment from the original offering) is participating
in the Shelf Registration Statement, shall use its best efforts to reflect in
each such document, when so filed with the Commission, such comments as such
Initial Purchaser reasonably may propose; and (ii) include the names of the
Holders who propose to sell Securities pursuant to the Shelf Registration
Statement as selling securityholders; PROVIDED, HOWEVER, that Holders shall have
furnished to the Company on a timely basis such information regarding the Holder
as the Company may require pursuant to Section 2(l) hereof. Notwithstanding the
foregoing, if a properly completed and signed Selling Securityholder Notice and
Questionnaire in the form of Annex A (a "Questionnaire") to the Offering
Circular is received by the Company at least 5 business days prior to the
effective date of the Shelf Registration Statement or amendment thereto, the
Holder delivering such questionnaire shall be entitled to have its Securities
included in the Shelf Registration Statement or such amendment at the effective
date thereof. If the Company receives a properly completed and signed
Questionnaire thereafter, the Securities covered by such Questionnaire will be
included in the Shelf Registration Statement, and the Company shall file any
amendments to the Shelf Registration Statement or supplements to the Prospectus
as are necessary to permit such Holder to deliver the Prospectus to purchasers
of the Securities, as promptly as practicable after receipt of such properly
completed and signed Questionnaire but in no event more than 30 days after such
receipt; PROVIDED, HOWEVER, that the Company may take reasonable steps to
aggregate the additional Securities requested to be registered by Holders
delivering such Questionnaires for purposes of filing amendments to the Shelf
Registration Statement or supplements to the Prospectus so as to reduce the need
for multiple amendments or supplements, such that the Company shall not be
required to file more than one amendment or supplement during any thirty-day
period.

     (b) The Company shall give written notice to the Initial Purchasers and the
Holders of the Securities (which notice pursuant to clauses (ii)-(vi) hereof
shall be accompanied by an instruction to suspend the use of the Prospectus
until the requisite changes have been made):

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          (i)   when the Shelf Registration Statement or any amendment thereto
     has been filed with the Commission and when the Shelf Registration
     Statement or any post-effective amendment thereto has become effective;

          (ii)  of any request by the Commission for amendments or supplements
     to the Shelf Registration Statement or the prospectus included therein or
     for additional information;

          (iii) of the issuance by the Commission of any stop order suspending
     the effectiveness of the Shelf Registration Statement or the initiation of
     any proceedings for that purpose;

          (iv)  of the receipt by the Company or its legal counsel of any
     notification with respect to the suspension of the qualification of the
     Securities for sale in any jurisdiction or the initiation or threatening of
     any proceeding for such purpose;

          (v)   of the happening of any event that requires the Company to make
     changes in the Shelf Registration Statement or the Prospectus in order that
     the Shelf Registration Statement or the Prospectus does not contain an
     untrue statement of a material fact nor omit to state a material fact
     required to be stated therein or necessary to make the statements therein
     (in the case of the Prospectus, in light of the circumstances under which
     they were made) not misleading; and

          (vi)  the occurrence or existence of any pending corporate development
     with respect to the Company that the Company believes may be material and
     that, in the determination of the Company, makes it not in the best
     interest of the Company to allow continued availability of the Shelf
     Registration Statement and the Prospectus.

     (c) The Company shall use commercially reasonable efforts to obtain the
withdrawal at the earliest possible time, of any order suspending the
effectiveness of the Shelf Registration Statement or the lifting of any
suspension of the qualification (or exemption from qualification) of any of the
Securities for sale in any jurisdiction in which they have been qualified for
sale.

     (d) The Company shall furnish to each Holder of Securities included within
the coverage of the Shelf Registration, without charge, at least one copy of the
Shelf Registration Statement and any post-effective amendment thereto, including
financial statements and schedules, and, if the Holder so requests in writing,
all exhibits thereto (including those, if any, incorporated by reference).

     (e) The Company shall, during the Shelf Registration Period, deliver to
each Holder of Securities included within the coverage of the Shelf
Registration, without charge, as many copies of the Prospectus (including each
preliminary prospectus) included in the Shelf Registration Statement and any
amendment or supplement thereto as such person may reasonably request. The
Company consents, subject to the provisions of this Agreement, to the use of the
Prospectus or any amendment or supplement thereto by each of the selling Holders
of the Securities in connection with the offering and sale of the Securities
covered by the Prospectus, or any amendment or supplement thereto, included in
the Shelf Registration Statement.

     (f) Prior to any public offering of the Securities pursuant to the Shelf
Registration Statement, the Company shall register or qualify or cooperate with
the Holders of the Securities included therein and their respective counsel in
connection with the registration or qualification of the Securities for offer
and sale under the securities or "blue sky" laws of such states of the United
States as any Holder of the Securities reasonably requests in writing and do any
and all other acts or things necessary or advisable to enable the offer and sale
in such jurisdictions of the Securities covered by such Registration Statement;
PROVIDED, HOWEVER, that the Company shall not be required to (i) qualify
generally to do business in any jurisdiction where it is not then so qualified
or (ii) take any action which would subject it to general service of process or
to taxation in any jurisdiction where it is not then so subject.

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     (g) The Company shall cooperate with the Holders of the Securities to
facilitate the timely preparation and delivery of certificates representing the
Securities to be sold pursuant to any Registration Statement free of any
restrictive legends and in such denominations and registered in such names as
the Holders may request a reasonable period of time prior to sales of the
Securities pursuant to the Shelf Registration Statement.

     (h) Upon the occurrence of any event contemplated by paragraphs (ii)
through (v) of Section 2(b) above during the period for which the Company is
required to maintain an effective Shelf Registration Statement, the Company
shall promptly prepare and file a post-effective amendment to the Shelf
Registration Statement or an amendment or supplement to the Prospectus and any
other required document so that, as thereafter delivered to Holders or
purchasers of the Securities, the Prospectus will not contain an 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 light of the
circumstances under which they were made, not misleading. If the Company
notifies the Initial Purchasers and the Holders in accordance with paragraphs
(ii) through (v) of Section 2(b) above to suspend the use of the Prospectus
until the requisite changes to the Prospectus have been made, or the Company
otherwise notifies the Initial Purchasers and the Holders of its election to
suspend the availability of the Shelf Registration Statement and the Prospectus
pursuant to Section 2(b)(vi) above, then the Initial Purchasers and the Holders
shall suspend use of such prospectus, and the period of effectiveness of the
Shelf Registration Statement provided for in Section 1(b) above shall be
extended by the number of days from and including the date of the giving of such
notice to and including the date when the Initial Purchasers and the Holders
shall have been advised in writing by the Company that the Prospectus may be
used or have received such amended or supplemented prospectus pursuant to this
Section 2(h). The Company will use commercially reasonable efforts to ensure
that the use of the Prospectus may be resumed as promptly as is practicable,
except that in the case of suspension of the availability of the Shelf
Registration Statement and Prospectus pursuant to Section 2(b)(vi) above, the
Company shall not be required to take such action until such time as it shall no
longer determine that continued availability of the Shelf Registration Statement
and the Prospectus is not in the best interests of the Company. The Company
shall be entitled to exercise its right under this Section 2(h) to suspend the
availability of the Shelf Registration Statement or the Prospectus, without
incurring or accruing any obligation to pay Additional Interest pursuant to
Section 5(a), for a period not to exceed 60 consecutive days or for multiple
periods not to exceed, in the aggregate, more than 90 days in any 12-month
period.

     (i) Not later than the effective date of the Shelf Registration Statement,
the Company will provide CUSIP numbers for the Initial Securities and the Common
Stock registered under the Shelf Registration Statement, and provide the Trustee
with printed certificates for the Initial Securities, in a form eligible for
deposit with The Depository Trust Company.

     (j) The Company will use commercially reasonable efforts to comply with all
rules and regulations of the Commission to the extent and so long as they are
applicable to the Shelf Registration and will make generally available to its
security holders (or otherwise provide in accordance with Section 11(a) of the
Securities Act) an earnings statement satisfying the provisions of Section 11(a)
of the Securities Act, no later than 45 days after the end of a 12-month period
(or 90 days, if such period is a fiscal year) beginning with the first month of
the Company's first fiscal quarter commencing after the effective date of the
Shelf Registration Statement, which statement shall cover such 12-month period.

     (k) The Company shall cause the Indenture to be qualified under the Trust
Indenture Act of 1939, as amended, (the "TRUST INDENTURE ACT") in a timely
manner and containing such changes, if any, as shall be necessary for such
qualification. In the event that such qualification would require the
appointment of a new trustee under the Indenture, the Company shall appoint a
new trustee thereunder pursuant to the applicable provisions of the Indenture.

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     (l) The Company may require each Holder of Securities to be sold pursuant
to the Shelf Registration Statement to furnish to the Company such information,
including a properly completed and signed Questionnaire, regarding the Holder
and the distribution of the Securities as the Company may from time to time
reasonably require for inclusion in the Shelf Registration Statement, and the
Company may exclude from such registration the Securities of any Holder that
fails to furnish such information within a reasonable time after receiving such
request.

     (m) The Company shall enter into such customary agreements (including, if
requested, an underwriting agreement in customary form) and take all such other
actions, if any, as any Holder shall reasonably request in order to facilitate
the disposition of the Securities pursuant to the Shelf Registration.

     (n) The Company shall (i) make reasonably available for inspection by the
Holders, any underwriter participating in any disposition pursuant to the Shelf
Registration Statement and any attorney, accountant or other agent retained by
the Holders or any such underwriter, all relevant financial and other records,
pertinent corporate documents and properties of the Company and (ii) cause the
Company's officers, directors, employees, accountants and auditors to supply all
relevant information reasonably requested by the Holders or any such
underwriter, attorney, accountant or agent in connection with the Shelf
Registration Statement, in each case, as shall be reasonably necessary to enable
such persons, to conduct a reasonable investigation within the meaning of
Section 11 of the Securities Act; PROVIDED, HOWEVER, that the foregoing
inspection and information gathering shall be coordinated on behalf of the
Initial Purchasers by you and on behalf of the other parties, by one counsel
designated by and on behalf of such other parties as described in Section 3(b)
hereof; PROVIDED FURTHER, that any such persons requesting such information or
conducting such inspection shall first agree in writing with the Company that
any information that is reasonably and in good faith designated by the Company
as confidential at the time of delivery or inspection (as the case may be) of
such information shall be kept confidential by such persons, unless (1)
disclosure of such information is required by court or administrative order or
is necessary to respond to inquiries of regulatory authorities; (2) disclosure
of such information is required by law; (3) such information becomes generally
available to the public other than as a result of a disclosure or failure to
safeguard by any such person; or (4) such information becomes available to any
such person from a source other than the Company and such source is not bound by
a confidentiality agreement..

     (o) The Company, if requested by any Holder of Securities covered by the
Shelf Registration Statement in connection with an underwritten offering, shall
cause (i) its counsel to deliver an opinion and updates thereof relating to the
Securities in customary form addressed to such Holders and the managing
underwriters, if any, thereof, and dated, in the case of the initial opinion,
the effective date of such Shelf Registration Statement (it being agreed that
the matters to be covered by such opinion shall include, without limitation, but
subject to reasonable qualifications, the due incorporation and good standing of
the Company and its significant subsidiaries; the qualification of the Company
and its significant subsidiaries to transact business as foreign corporations;
the due authorization, execution and delivery of the relevant agreement of the
type referred to in Section 2(m) hereof; the due authorization, execution,
authentication and issuance, and the validity and enforceability, of the
Securities; the absence of material legal or governmental proceedings involving
the Company and its significant subsidiaries; the absence of governmental
approvals (other than those required by the Commission) required to be obtained
in connection with the Shelf Registration Statement, the offering and sale of
the Securities, or any agreement of the type referred to in Section 2(m) hereof;
the compliance as to form of the Shelf Registration Statement and any documents
incorporated by reference therein and of the Indenture with the requirements of
the Securities Act and the Trust Indenture Act, respectively; and, as of the
date of the opinion and as of the effective date of the Shelf Registration
Statement or most recent post-effective amendment thereto, as the case may be,
the absence from the Shelf Registration Statement and the prospectus included
therein, as then amended or supplemented, and from any documents incorporated by
reference therein of an untrue statement of a material fact or the omission to
state therein a material fact required to be stated therein or necessary to make
the statements therein not misleading (in the case of any such documents, in the
light of the circumstances existing at the time that such documents were filed
with the Commission under the Exchange

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Act of 1934, as amended (the "EXCHANGE ACT")); (ii) its officers to execute and
deliver all customary documents and certificates and updates thereof requested
by any underwriters of the Securities and (iii) its independent public
accountants and the independent public accountants with respect to any other
entity for which financial information is provided in the Shelf Registration
Statement to provide to the selling Holders of the applicable Securities and any
underwriter therefor a comfort letter in customary form and covering matters of
the type customarily covered in comfort letters in connection with primary
underwritten offerings, subject to receipt of appropriate documentation as
contemplated, and only if permitted, by Statement of Auditing Standards No. 72;
PROVIDED, HOWEVER, that in connection with an underwritten offering covered by
the Shelf Registration Statement the Company may require any underwriter to
agree to provisions substantially in the form of Section 4 hereof.

     (p) The Company will use commercially reasonable efforts to (a) if the
Initial Securities have been rated prior to the initial sale of such Initial
Securities, confirm such ratings will apply to the Securities covered by a
Registration Statement, or (b) if the Initial Securities were not previously
rated, cause the Securities covered by a Registration Statement to be rated with
the appropriate rating agencies, if so requested by holders of a majority in
aggregate principal amount of Securities covered by the Shelf Registration
Statement, or by the managing underwriters, if any.

     (q) In the event that any broker-dealer registered under the Exchange Act
shall underwrite any Securities or participate as a member of an underwriting
syndicate or selling group or "assist in the distribution" (within the meaning
of the Conduct Rules (the "RULES") of the National Association of Securities
Dealers, Inc. ("NASD")) thereof, whether as a Holder of such Securities or as an
underwriter, a placement or sales agent or a broker or dealer in respect
thereof, or otherwise, the Company will assist such broker-dealer in complying
with the requirements of such Rules, including, without limitation, by (i) if
such Rules, including Rule 2720, shall so require, engaging a "qualified
independent underwriter" (as defined in Rule 2720) to participate in the
preparation of the Shelf Registration Statement relating to such Securities, to
exercise usual standards of due diligence in respect thereto and, if any portion
of the offering contemplated by such Registration Statement is an underwritten
offering or is made through a placement or sales agent, to recommend the yield
of such Securities, (ii) indemnifying any such qualified independent underwriter
to the extent of the indemnification of underwriters provided in Section 5
hereof and (iii) providing such information to such broker-dealer as may be
required in order for such broker-dealer to comply with the requirements of the
Rules.

     (r) The Company shall use commercially reasonable efforts to take all other
steps necessary to effect the registration of the Securities covered by a
Registration Statement contemplated hereby.

     (s) The Company shall as promptly as practicable (if reasonably requested
by any Holder who proposes to sell Securities pursuant to the Shelf Registration
Statement or by an Initial Purchaser (with respect to any portion of an unsold
allotment from the original offering if such Initial Purchaser is participating
in the Shelf Registration Statement)) incorporate in a prospectus supplement or
post-effective amendment to the Shelf Registration Statement such information
regarding such Holder as such Holder or Initial Purchaser shall reasonably
determine to be required to be included therein and make any required filings of
such prospectus supplement or such post-effective amendment; PROVIDED that the
Company shall not be required to take any actions under this Section 2(s) that
are not, in the reasonable opinion of counsel for the Company, in compliance
with applicable law.

     3. REGISTRATION EXPENSES. (a) Except as otherwise provided in Section 7
hereof, all expenses incident to the Company's performance of and compliance
with this Agreement will be borne by the Company, regardless of whether a
Registration Statement is ever filed or becomes effective, including without
limitation;

          (i)   all registration and filing fees and expenses;

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          (ii)  all fees and expenses of compliance with federal securities and
     state "blue sky" or securities laws;

          (iii) all expenses of printing (including printing certificates for
     the Securities to be issued and printing of Prospectuses), messenger and
     delivery services and telephone;

          (iv)  all fees and disbursements of counsel for the Company;

          (v)   all application and filing fees in connection with listing the
     Securities on a national securities exchange or automated quotation system
     pursuant to the requirements hereof; and

          (vi)  all fees and disbursements of independent certified public
     accountants of the Company (including the expenses of any special audit and
     comfort letters required by or incident to such performance).

The Company will bear its internal expenses (including, without limitation, all
salaries and expenses of its officers and employees performing legal or
accounting duties), the expenses of any annual audit and the fees and expenses
of any person, including special experts, retained by the Company.

     (b) Except as otherwise provided in Section 7 hereof, in connection with
the Shelf Registration Statement required by this Agreement, the Company will
reimburse the Initial Purchasers and the Holders of Securities covered by the
Shelf Registration Statement, for the reasonable fees and disbursements of not
more than one counsel, designated by the Holders of a majority in principal
amount of the Securities covered by the Shelf Registration Statement (provided
that Holders of Common Stock issued upon the conversion of the Initial
Securities shall be deemed to be Holders of the aggregate principal amount of
Initial Securities from which such Common Stock was converted) to act as counsel
for the Holders in connection therewith.

     4. INDEMNIFICATION. (a) The Company agrees to indemnify and hold harmless
each Holder and each person, if any, who controls such Holder within the meaning
of the Securities Act or the Exchange Act (each Holder, and such controlling
persons are referred to collectively as the "INDEMNIFIED PARTIES") from and
against any losses, claims, damages or liabilities, joint or several, or any
actions in respect thereof (including, but not limited to, any losses, claims,
damages, liabilities or actions relating to purchases and sales of the
Securities) to which each Indemnified Party may become subject under the
Securities Act, the Exchange Act or otherwise, insofar as such losses, claims,
damages, liabilities or actions arise out of or are based upon any untrue
statement or alleged untrue statement of a material fact contained in the Shelf
Registration Statement or Prospectus including any document incorporated by
reference therein, or in any amendment or supplement thereto or in any
preliminary prospectus relating to the Shelf Registration, or arise out of, or
are based upon, the omission or alleged omission to state in the Shelf
Registration Statement or Prospectus, including any document incorporated by
reference therein, or in any amendment or supplement thereto or in any
preliminary prospectus relating to the Shelf Registration, a material fact
required to be stated therein or necessary to make the statements therein not
misleading, and shall reimburse, as incurred, the Indemnified Parties for any
legal or other expenses reasonably incurred by them in connection with
investigating or defending any such loss, claim, damage, liability or action in
respect thereof; PROVIDED, HOWEVER, that (i) the Company shall not be liable in
any such case to the extent that such loss, claim, damage or liability arises
out of or is based upon any untrue statement or alleged untrue statement or
omission or alleged omission made in the Shelf Registration Statement or
Prospectus or in any amendment or supplement thereto or in any preliminary
prospectus relating to the Shelf Registration in reliance upon and in conformity
with written information pertaining to such Holder and furnished to the Company
by or on behalf of such Holder specifically for inclusion therein and (ii) with
respect to any untrue statement or omission or alleged untrue statement or
omission made in any preliminary prospectus relating to the Shelf Registration
Statement, the indemnity agreement contained in this subsection (a) shall not
inure to the benefit of any Holder from whom the person asserting any such
losses, claims, damages or liabilities

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purchased the Securities concerned, to the extent that a prospectus relating to
such Securities was required to be delivered by such Holder under the Securities
Act in connection with such purchase and any such loss, claim, damage or
liability of such Holder results from the fact that there was not sent or given
to such person, at or prior to the written confirmation of the sale of such
Securities to such person, a copy of the final prospectus if the Company had
previously furnished copies thereof to such Holder; PROVIDED FURTHER, HOWEVER,
that this indemnity agreement will be in addition to any liability which the
Company may otherwise have to such Indemnified Party. The Company shall also
indemnify underwriters that participate in an offering of Securities under the
Shelf Registration Statement, their officers and directors and each person who
controls such underwriters within the meaning of the Securities Act or the
Exchange Act to the same extent as provided above with respect to the
indemnification of the Holders of the Securities if requested by such Holders.

     (b) Each Holder, severally and not jointly, will indemnify and hold
harmless the Company, its officers and directors and each person, if any, who
controls the Company within the meaning of the Securities Act or the Exchange
Act from and against any losses, claims, damages or liabilities or any actions
in respect thereof, to which the Company or any such controlling person may
become subject under the Securities Act, the Exchange Act or otherwise, insofar
as such losses, claims, damages, liabilities or actions arise out of or are
based upon any untrue statement or alleged untrue statement of a material fact
contained in the Shelf Registration Statement or Prospectus or in any amendment
or supplement thereto or in any preliminary prospectus relating to the Shelf
Registration, or arise out of or are based upon the omission or alleged omission
to state in the Shelf Registration Statement or Prospectus or in any amendment
or supplement thereto or in any preliminary prospectus relating to the Shelf
Registration, therein a material fact necessary to make the statements therein
not misleading, but in each case only to the extent that the untrue statement or
omission or alleged untrue statement or omission was made in reliance upon and
in conformity with written information pertaining to such Holder and furnished
to the Company by or on behalf of such Holder specifically for inclusion
therein; and, subject to the limitation set forth immediately preceding this
clause, shall reimburse, as incurred, the Company for any legal or other
expenses reasonably incurred by the Company or any such controlling person in
connection with investigating or defending any loss, claim, damage, liability or
action in respect thereof. This indemnity agreement will be in addition to any
liability which such Holder may otherwise have to the Company or any of its
controlling persons.

     (c) Promptly after receipt by an indemnified party under this Section 4 of
notice of the commencement of any action or proceeding (including a governmental
investigation), such indemnified party will, if a claim in respect thereof is to
be made against the indemnifying party under this Section 4, notify the
indemnifying party of the commencement thereof; but the omission so to notify
the indemnifying party will not, in any event, relieve the indemnifying party
from any obligations to any indemnified party under this agreement other than
the indemnification obligation provided in paragraph (a) or (b) above. In case
any such action is brought against any indemnified party, and it notifies the
indemnifying party of the commencement thereof, the indemnifying party will be
entitled to participate therein and, to the extent that it may wish, jointly
with any other indemnifying party similarly notified, to assume the defense
thereof, with counsel reasonably satisfactory to such indemnified party, and
after notice from the indemnifying party to such indemnified party of its
election so to assume the defense thereof the indemnifying party will not be
liable to such indemnified party under this Section 4 for any legal or other
expenses, other than reasonable costs of investigation, subsequently incurred by
such indemnified party in connection with the defense thereof. Notwithstanding
the indemnifying party's election to assume the defense of the indemnified party
in an action, the indemnified party shall have the right to employ separate
counsel (including local counsel) and the indemnifying party shall bear the
reasonable fees, costs and expenses of such separate counsel (and local counsel)
if (i) the use of counsel chosen by the indemnifying party to represent the
indemnified party would present such counsel with a conflict of interest, (ii)
the actual or potential defendants in, or targets of, any such action include
both the indemnified party and the indemnifying party and the indemnified party
shall have reasonably concluded 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, (iii) the indemnifying party shall not have
employed counsel reasonably satisfactory to the indemnified party to

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represent the indemnified party within a reasonable time after notice from the
indemnified party of the institution of such action or (iv) the indemnifying
party shall authorize the indemnified party to employ separate counsel at the
expense of the indemnifying party. No indemnifying party shall, without the
prior written consent of the indemnified party (which consent shall not be
unreasonably withheld or delayed), effect any settlement or compromise of, or
consent to the entry of any judgment with respect to, any pending or threatened
action in respect of which any indemnified party is or could have been a party
and indemnity could have been sought hereunder by such indemnified party unless
such settlement, compromise or judgment (i) includes an unconditional release of
such indemnified party from all liability on any claims that are the subject
matter of such action, and (ii) does not include a statement as to or an
admission of fault, culpability or a failure to act by or on behalf of any
indemnified party. In no event will any indemnifying party be liable for the
fees and disbursements of more than one counsel (plus the fees and disbursements
of local counsel) for all indemnified parties in connection with any one action
or separate but similar or related actions in the same jurisdiction arising out
of the same general obligations or circumstances, unless such indemnified party
reasonably determines that the representation of the indemnified party and any
other party to such action or actions by the same counsel would present a
conflict of interest. No indemnified party shall, without the prior written
consent of the indemnifying party, which consent shall not be unreasonably
withheld or delayed, effect any settlement or compromise, or consent to the
entry of any judgment with respect to any pending or threatened action in
respect of which any indemnifying party is or could have been a party or
indemnity could have been sought hereunder from such indemnifying party.

     (d) If the indemnification provided for in this Section 4 is unavailable or
insufficient to hold harmless an indemnified party under subsections (a) or (b)
above, then each indemnifying party shall contribute to the amount paid or
payable by such indemnified party as a result of the losses, claims, damages or
liabilities (or actions in respect thereof) referred to in subsection (a) or (b)
above in such proportion as is appropriate to reflect the relative fault of the
indemnifying party or parties on the one hand and the indemnified party on the
other in connection with the statements or omissions that resulted in such
losses, claims, damages or liabilities (or actions in respect thereof) as well
as any other relevant equitable considerations. The relative fault of the
parties shall be determined by reference to, among other things, whether the
untrue or alleged untrue statement of a material fact or the omission or alleged
omission to state a material fact relates to information supplied by the Company
on the one hand or such Holder or such other indemnified party, as the case may
be, on the other, and the parties' relative intent, knowledge, access to
information and opportunity to correct or prevent such statement or omission.
The amount paid by an indemnified party as a result of the losses, claims,
damages or liabilities referred to in the first sentence of this subsection (d)
shall be deemed to include any legal or other expenses reasonably incurred by
such indemnified party in connection with investigating or defending any action
or claim which is the subject of this subsection (d). Notwithstanding any other
provision of this Section 4(d), the Holders shall not be required to contribute
any amount in excess of the amount by which the net proceeds received by such
Holders from the sale of the Securities pursuant to the Shelf Registration
Statement exceeds the amount of damages which such Holders have otherwise been
required to pay by reason of such untrue or alleged untrue statement or omission
or alleged omission. 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. For purposes of this subsection (d), each person, if any, who
controls such indemnified party within the meaning of the Securities Act or the
Exchange Act shall have the same rights to contribution as such indemnified
party and each person, if any, who controls the Company within the meaning of
the Securities Act or the Exchange Act shall have the same rights to
contribution as the Company.

     (e) The agreements contained in this Section 4 shall survive the sale of
the Securities pursuant to the Shelf Registration Statement and shall remain in
full force and effect, regardless of any termination or cancellation of this
Agreement or any investigation made by or on behalf of any indemnified party.

     5. ADDITIONAL INTEREST UNDER CERTAIN CIRCUMSTANCES. (a) Subject to the last
sentence of Section 2(h), Additional interest (the "ADDITIONAL INTEREST") with
respect to the Transfer Restricted Securities shall

                                        9
<Page>

be assessed as follows if any of the following events occur (each such event in
clauses (i) through (iii) below being herein called a "REGISTRATION DEFAULT"):

          (i)   the Shelf Registration Statement has not been filed with the
     Commission by the 90th day after the first date of original issuance of the
     Initial Securities;

          (ii)  the Shelf Registration Statement has not been declared effective
     by the Commission by the 180th day after the first date of original issue
     of the Initial Securities; or

          (iii) the Shelf Registration Statement is declared effective by the
     Commission but, prior to the end of the Shelf Registration Period, (A) the
     Shelf Registration Statement thereafter ceases to be effective or (B) the
     Shelf Registration Statement or the Prospectus ceases to be usable in
     connection with resales of Transfer Restricted Securities (as defined
     below) during the periods specified herein because either (1) any event
     occurs as a result of which the Prospectus forming part of such Shelf
     Registration Statement would 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 under which they were made not
     misleading, or (2) it shall be necessary to amend such Shelf Registration
     Statement or supplement the related prospectus, to comply with the
     Securities Act or the Exchange Act or the respective rules thereunder, or
     (3) the Company exercises its right pursuant to Section 2(b)(vi) to suspend
     the use of the Shelf Registration Statement.

Each of the foregoing will constitute a Registration Default whatever the reason
for any such event and whether it is voluntary or involuntary or is beyond the
control of the Company or pursuant to operation of law or as a result of any
action or inaction by the Commission.

     Additional Interest shall accrue on the Transfer Restricted Securities over
and above the interest set forth in the title of the Initial Securities from and
including the date on which any such Registration Default shall occur to but
excluding the earlier of (i) the date on which all such Registration Defaults
have been cured and (ii) the day following the last day of the Shelf
Registration Period, at a rate of 0.50% per annum (the "ADDITIONAL INTEREST
RATE") of the aggregate principal amount of the Initial Securities that are
Transfer Restricted Securities. In the case of Initial Securities that have been
converted into or exchanged for Common Stock, Additional Interest shall accrue
at a rate per annum of 0.50% on an amount (the "Converted Amount of Common
Stock") equal to the product of (x) the Applicable Conversion Price multiplied
by (y) the aggregate number of such shares of Common Stock that are Transfer
Restricted Securities outstanding as of such date of determination. For purposes
of this Section 5, "APPLICABLE CONVERSION PRICE" as of any date of determination
means the Conversion Price (as defined in the Indenture) in effect as of such
date of determination or, if no Initial Securities are then outstanding, the
Conversion Price that would be in effect were Initial Securities then
outstanding.

     The Trustee shall be entitled, on behalf of Holders of Securities, to seek
any available remedy for the enforcement of this Agreement, including for the
payment of any Additional Interest.

     All of the Company's obligations set forth in this Section 5 that are
outstanding with respect to any Transfer Restricted Security at the time such
Security ceases to be a Transfer Restricted Security shall survive until such
time as all such obligations with respect to such Security have been satisfied
in full.

     (b) A Registration Default referred to in Section 5(a)(iii) hereof shall be
deemed not to have occurred and be continuing in relation to the Shelf
Registration Statement or the related prospectus if (i) such Registration
Default has occurred solely as a result of (x) the filing of a post-effective
amendment to the Shelf Registration Statement to incorporate annual audited
financial information with respect to the Company where such post-effective
amendment is not yet effective and needs to be declared effective to permit
Holders to use the related prospectus or (y) other material events, with respect
to the Company that

                                       10
<Page>

would need to be described in such Shelf Registration Statement or the related
prospectus and (ii) in the case of clause (y), the Company is proceeding
promptly and in good faith to amend or supplement the Shelf Registration
Statement and related prospectus to describe such events as required by
paragraph 2(h) hereof; PROVIDED, HOWEVER, that in any case if such Registration
Default occurs for a continuous period in excess of 30 days, Additional Interest
shall be payable in accordance with the Section 5(a) from the day such
Registration Default occurs until such Registration Default is cured.

     (c) Any amounts of Additional Interest due pursuant to Section 5(a) will be
payable in cash on the regular interest payment dates with respect to the
Initial Securities. The amount of Additional Interest will be determined (i) in
the case of Initial Securities that are Transfer Restricted Securities, by
multiplying the applicable Additional Interest Rate by the principal amount of
such Initial Securities and (ii) in the case of shares of Common Stock that are
Transfer Restricted Securities, by multiplying the applicable Additional
Interest Rate by the Converted Amount of Common Stock, in each case, further
multiplied by a fraction, the numerator of which is the number of days such
Additional Interest Rate was applicable during such period (determined on the
basis of a 360-day year comprised of twelve 30-day months), and the denominator
of which is 360.

     (d) "TRANSFER RESTRICTED SECURITIES" means each Security until (i) the date
on which such Security has been effectively registered under the Securities Act
and disposed of in accordance with the Shelf Registration Statement or (iv) the
date on which such Security is distributed to the public pursuant to Rule 144
under the Securities Act or is saleable pursuant to Rule 144(k) under the
Securities Act.

     6. RULES 144 AND 144A. The Company shall use commercially reasonable
efforts to file the reports required to be filed by it under the Securities Act
and the Exchange Act in a timely manner and, if at any time the Company is not
required to file such reports, it will, upon the request of any Holder, make
publicly available other information so long as necessary to permit sales of
their securities pursuant to Rules 144 and 144A. The Company covenants that it
will take such further action as any Holder may reasonably request, all to the
extent required from time to time to enable such Holder to sell Transfer
Restricted Securities without registration under the Securities Act within the
limitation of the exemptions provided by Rules 144 and 144A (including the
requirements of Rule 144A(d)(4)). The Company will provide a copy of this
Agreement to prospective purchasers of Securities identified to the Company by
the Initial Purchasers upon request. Upon the request of any Holder, the Company
shall deliver to such Holder a written statement as to whether it has complied
with such requirements. Notwithstanding the foregoing, nothing in this Section 6
shall be deemed to require the Company to register any of its securities
pursuant to the Exchange Act.

     7. UNDERWRITTEN REGISTRATIONS. If any of the Transfer Restricted Securities
covered by the Shelf Registration are to be sold in an underwritten offering,
the investment banker or investment bankers and manager or managers that will
administer the offering ("MANAGING UNDERWRITERS") will be selected by the
holders of a majority in aggregate principal amount of such Transfer Restricted
Securities to be included in such offering (provided that holders of Common
Stock issued upon conversion of the Initial Securities shall not be deemed
holders of Common Stock, but shall be deemed to be holders of the aggregate
principal amount of Initial Securities from which such Common Stock was
converted; PROVIDED, HOWEVER, that (a) such investment banker or bankers must be
reasonably satisfactory to the Company and (b) the Company shall not be required
to arrange for or participate in more than one underwritten offering during the
Shelf Registration Period..

     No person may participate in any underwritten registration hereunder unless
such person (i) agrees to sell such person's Transfer Restricted Securities on
the basis reasonably provided in any underwriting arrangements approved by the
persons entitled hereunder to approve such arrangements, (ii) completes and
executes all questionnaires, powers of attorney, indemnities, underwriting
agreements and other documents reasonably required under the terms of such
underwriting arrangements and (iii) at least 20% of the outstanding Transfer
Restricted Securities are included in such underwritten offering. The holders

                                       11
<Page>

participating in any underwritten offering shall be responsible for any expenses
customarily borne by selling securityholders, including underwriting discounts
and commissions and fees and expenses of counsel to the selling securityholders
to the extent not required to be paid by the Company pursuant to Section 3
hereof..

     8. MISCELLANEOUS.

     (a) REMEDIES. The Company acknowledges and agrees that any failure by the
Company to comply with its obligations under Section 1 hereof may result in
material irreparable injury to the Initial Purchasers or the Holders for which
there is no adequate remedy at law, that it will not be possible to measure
damages for such injuries precisely and that, in the event of any such failure,
the Initial Purchasers or any Holder may obtain such relief as may be required
to specifically enforce the Company's obligations under Sections 1 hereof. The
Company further agrees to waive the defense in any action for specific
performance that a remedy at law would be adequate.

     (b) NO INCONSISTENT AGREEMENTS. The Company will not on or after the date
of this Agreement enter into any agreement with respect to its securities that
is inconsistent with the rights granted to the Holders in this Agreement or
otherwise conflicts with the provisions hereof. The rights granted to the
Holders hereunder do not in any way conflict with and are not inconsistent with
the rights granted to the holders of the Company's securities under any
agreement in effect on the date hereof.

     (c) AMENDMENTS AND WAIVERS. The provisions of this Agreement may not be
amended, modified or supplemented, and waivers or consents to departures from
the provisions hereof may not be given, except by the Company and the written
consent of the holders of a majority in principal amount of the Initial
Securities affected by such amendment, modification, supplement, waiver or
consents (provided that holders of Common Stock issued upon conversion of
Initial Securities shall not be deemed holders of Common Stock, but shall be
deemed to be holders of the aggregate principal amount of Initial Securities
from which such Common Stock was converted). Without the consent of the Holder
of each Initial Security, however, no modification may change the provisions
relating to the payment of Additional Interest.

     (d) NOTICES. All notices and other communications provided for or permitted
hereunder shall be made in writing by hand delivery, first-class mail, facsimile
transmission, or air courier which guarantees overnight delivery:

          (1)   if to a Holder of the Securities, at the most current address
     given by such Holder to the Company.

          (2)   if to the Initial Purchasers;

                      Credit Suisse First Boston Corporation
                      Eleven Madison Avenue
                      New York, NY 10010-3629
                      Fax No.:  (212) 325-8278
                      Attention:  Transactions Advisory Group

          with a copy to:

                      Wilson Sonsini Goodrich & Rosati
                      Professional Corporation
                      650 Page Mill Road
                      Palo Alto, CA 94304-1050
                      Attention:  John A. Fore

                                       12
<Page>

          (3) if to the Company, at its address as follows:

                      Cymer, Inc.
                      16750 Via Del Campo Court
                      San Diego, CA 92127
                      Attention:  Chief Financial Officer

          with a copy to:

                      Cooley Godward LLP
                      4401 Eastgate Mall
                      San Diego, CA 92121-1909
                      Attention: D. Bradley Peck

     All such notices and communications shall be deemed to have been duly
given: at the time delivered by hand, if personally delivered; three business
days after being deposited in the mail, postage prepaid, if mailed; when receipt
is acknowledged by recipient's facsimile machine operator, if sent by facsimile
transmission; and on the day delivered, if sent by overnight air courier
guaranteeing next day delivery.

     (e) THIRD PARTY BENEFICIARIES. The Holders shall be third party
beneficiaries to the agreements made hereunder between the Company, on the one
hand, and the Initial Purchasers, on the other hand, and shall have the right to
enforce such agreements directly to the extent they may deem such enforcement
necessary or advisable to protect their rights or the rights of Holders
hereunder.

     (f) SUCCESSORS AND ASSIGNS. This Agreement shall be binding upon the
Company and its successors and assigns.

     (g) COUNTERPARTS. This Agreement may be executed in any number of
counterparts and by the parties hereto in separate counterparts, each of which
when so executed shall be deemed to be an original and all of which taken
together shall constitute one and the same agreement.

     (h) HEADINGS. The headings in this Agreement are for convenience of
reference only and shall not limit or otherwise affect the meaning hereof.

     (i) GOVERNING Law. THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED IN
ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO PRINCIPLES
OF CONFLICTS OF LAWS.

     The Company hereby submits to the non-exclusive jurisdiction of the Federal
and state courts in the Borough of Manhattan in the City of New York in any suit
or proceeding arising out of or relating to this Agreement or the transactions
contemplated hereby.

     (j) SEVERABILITY. If any one or more of the provisions contained herein, or
the application thereof in any circumstance, is held invalid, illegal or
unenforceable, the validity, legality and enforceability of any such provision
in every other respect and of the remaining provisions contained herein shall
not be affected or impaired thereby.

     (k) SECURITIES HELD BY THE COMPANY. Whenever the consent or approval of
Holders of a specified percentage of principal amount of Securities is required
hereunder, Securities held by the Company or its

                                       13
<Page>

affiliates (other than subsequent Holders of Securities if such subsequent
Holders are deemed to be affiliates solely by reason of their holdings of such
Securities) shall not be counted in determining whether such consent or approval
was given by the Holders of such required percentage.

     If the foregoing is in accordance with your understanding of our agreement,
please sign and return to the Company a counterpart hereof, whereupon this
instrument, along with all counterparts, will become a binding agreement among
the several Initial Purchasers and the Company in accordance with its terms.

                                            Very truly yours,

                                            CYMER, INC.


                                            by    /s/ NANCY J. BAKER
                                                  ------------------------------
                                                  Name:
                                                  Title:


The foregoing Registration
Rights Agreement is hereby confirmed
and accepted as of the date first
above written.

CREDIT SUISSE FIRST BOSTON CORPORATION
MERRILL LYNCH, PIERCE, FENNER & SMITH INCORPORATED

By:  CREDIT SUISSE FIRST BOSTON CORPORATION

by   /s/ FRANCISCO PARET
     ------------------------------------
     Name:  FRANCISCO PARET
     Title: DIRECTOR