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                                                                    EXHIBIT 10.3




                             Mykrolis Corporation

                       2001 EMPLOYEE STOCK PURCHASE PLAN


SECTION 1.  PURPOSE OF PLAN

     The Mykrolis Corporation 2001 Employee Stock Purchase Plan (the "Plan") is
intended to provide a method by which eligible employees of Mykrolis
Corporation, a Delaware corporation ("Mykrolis"), and such of its Subsidiaries
as the Board of Directors of Mykrolis (the "Board of Directors") may from time
to time designate (Mykrolis and such Subsidiaries being hereinafter referred to
as the "Company") may use voluntary, systematic payroll deductions to purchase
shares of common stock, $.01 par value of Mykrolis (such common stock being
hereafter referred to as "Stock") and thereby acquire an interest in the future
of Mykrolis.  For purposes of the Plan, a "Subsidiary" is any corporation that
would be treated as a subsidiary of Mykrolis under Section 424(f) of the
Internal Revenue Code of 1986, as amended (the "Code").  The Plan is intended to
qualify under Section 423 of the Code and shall be construed accordingly.

SECTION 2.  OPTIONS TO PURCHASE STOCK

     Under the Plan, there is available an aggregate of not more than [    ]
shares of Stock (subject to adjustment as provided in Section 15) for sale
pursuant to the exercise of options ("Options") granted under the Plan to
employees of the Company ("Employees") who meet the eligibility requirements set
forth in Section 3 hereof ("Eligible Employees").  The Stock to be delivered
upon exercise of Options under the Plan may be either shares of authorized but
unissued Stock or shares of reacquired Stock, as the Board of Directors may
determine.

SECTION 3.  ELIGIBLE EMPLOYEES

     Except as otherwise provided below, each Employee of the Company will be
eligible to participate in the Plan.

     (a)   Any Employee who immediately after the grant of an Option would own
(or pursuant to Section 423(b)(3) of the Code would be deemed to own) stock
possessing 5% or more of the total combined voting power or value of all classes
of stock of the employer corporation or of its parent or subsidiary
corporations, as defined in Section 424 of the Code, will not be eligible to
receive an Option to purchase Stock pursuant to the Plan.

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     (b)   No Employee will be granted an Option under the Plan that would
permit his or her rights to purchase shares of stock under all employee stock
purchase plans of the employer corporation and parent and subsidiary
corporations, as defined in Section 424 of the Code, to accrue at a rate which
exceeds $25,000 in fair market value of such stock (determined at the time the
Option is granted) for each calendar year during which any such Option granted
to such Employee is outstanding at any time, as provided in Section 423 of the
Code.

     (c)   The following categories of Employees shall not be eligible to
participate in the Plan:  (i) Employees whose customary employment for the
Company is twenty (20) hours or less per week, (ii) Employees whose customary
employment for the Company is for not more than five (5) months in any calendar
year.

SECTION 4.  METHOD OF PARTICIPATION

     The periods [January 1 to June 30] and [July 1 to December 31] of each year
will be termed "Option Periods."  Each person who is an Eligible Employee on the
date that is 15 days prior to an Option Period and will be an Eligible Employee
on the first day of such Option Period may elect to participate in the Plan by
executing and delivering, at least 15 days prior to the first day of such Option
Period, a payroll deduction authorization in accordance with Section 5.  Such
Employee will thereby become a participant ("Participant") on the first day of
such Option Period and will remain a Participant until his or her participation
is terminated as provided in the Plan.

SECTION 5.  PAYROLL DEDUCTION

     The payroll deduction authorization will request withholding at a rate (in
whole percentages) of not less than 1% nor more than 10% from the Participant's
Compensation by means of substantially equal payroll deductions over the Option
Period from payroll periods ending in the Option Period.  For purposes of the
Plan, "Compensation" means base pay, overtime, bonuses and other remuneration
paid by the Company and includible in a Participant's taxable income, plus any
such amounts that would be includible in the Participant's taxable income but
for a deferral election under Section 401(k) of the Code, but not including
income arising from the grant or vesting of a stock option or other stock award
or from the disposition of stock acquired under such an award.  A Participant
may change the withholding rate of his or her payroll deduction authorization by
written notice delivered to the Company at least 15 days prior to the first day
of the Option Period as to which the change is to be effective.  All amounts
withheld in accordance with a Participant's payroll deduction authorization will
be credited to a withholding account maintained in the Participant's name on the
books of the Company.  Amounts credited to the withholding account shall belong
to the Company and shall not be required to be set aside in trust or otherwise
segregated from the Company's general assets.


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SECTION 6.  GRANT OF OPTIONS

     Each person who is a Participant on the first day of an Option Period will
be granted, as of such day and for such Period, an Option entitling the
Participant to acquire shares of Stock equal in number to the lesser of:

           (a)   the whole number (disregarding any fractional share amount)
     determined by dividing $12,500 by the fair market value of one share of
     Stock on the first day of the Option Period; and

           (b)   the number (rounded down to the nearest whole number)
     determined by dividing (i) the balance credited to the Participant's
     withholding account on the last day of the Option Period, by (ii) the
     purchase price per share of the Stock determined under Section 7.

Mykrolis will reduce, on a substantially proportionate basis, the number of
shares of Stock purchasable by each Participant upon exercise of his or her
Option for an Option Period in the event that the number of shares then
available under the Plan is insufficient.  Option grants under this Section 6
shall be automatic and need not be separately documented.

SECTION 7.  PURCHASE PRICE

     The purchase price of Stock issued pursuant to the exercise of an Option
will be 85% of the fair market value of the Stock at (a) the time of grant of
the Option or (b) the time at which the Option is deemed exercised, whichever is
less.  Fair market value will mean the Closing Price of the Stock.  The "Closing
Price" of the Stock on any business day will be the last sale price, regular
way, with respect to such Stock, or, in case no such sale takes place on such
day, the average of the closing bid and asked prices, regular way, with respect
to such Stock, in either case as reported in the principal consolidated
transaction reporting system with respect to securities listed or admitted to
trading on the New York Stock Exchange; or, if such Stock is not listed or
admitted to trading on the New York Stock Exchange, as reported in the principal
consolidated transaction reporting system with respect to securities listed on
the principal national securities exchange on which such Stock is listed or
admitted to trading; or, if such Stock is not listed or admitted to trading, the
last quoted price with respect to such Stock, or, if not so quoted, the average
of the high bid and low asked prices in the over-the-counter market with respect
to such Stock, as reported by the National Association of Securities Dealers,
Inc. Automated Quotation System or such other similar system then in use; or, if
on any such date such Stock is not quoted by any such organization, the average
of the closing bid and asked prices with respect to such Stock, as furnished by
a professional market maker making a market in such Stock selected by the Board
of Directors in good faith; or, if no such market maker is available, the fair
market value of such Stock as of such day as determined in good faith by the
Board of Directors.


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SECTION 8.  EXERCISE OF OPTIONS

     If any Employee is a Participant in the Plan on the last business day of an
Option Period, he or she will be deemed to have exercised the Option granted to
him or her for that Period.  Upon such exercise, the Company will apply the
balance of the Participant's withholding account to the purchase of the number
of whole shares of Stock determined under Section 6 and as soon as practicable
thereafter will issue and deliver certificates for said shares to the
Participant or otherwise evidence the transfer of ownership of said shares and
will return to him or her the balance, if any, of his or her withholding account
in excess of the total purchase price of the shares so issued; provided, that if
the balance left in the account consists solely of an amount equal to the value
of a fractional share it will be retained in the Account and carried over to the
next Period.  No fractional shares will be issued hereunder.

     Notwithstanding anything herein to the contrary, Mykrolis' obligation to
issue and deliver shares of Stock under the Plan will be subject to the approval
required of any governmental authority in connection with the authorization,
issuance, sale or transfer of said shares, to any requirements of any national
securities exchange applicable thereto, and to compliance by Mykrolis with other
applicable legal requirements in effect from time to time.

SECTION 9.  INTEREST

     No interest will be payable on withholding accounts.

SECTION 10.  CANCELLATION AND WITHDRAWAL

     A Participant who holds an Option under the Plan may at any time prior to
exercise thereof under Section 8 cancel all (but not less than all) of his or
her Options by written notice delivered to the Company.  Upon such cancellation,
the balance in the Participant's withholding account will be returned to the
Participant.

     A Participant may terminate his or her payroll deduction authorization as
of any date by written notice delivered to the Company and will thereby cease to
be a Participant as of such date.  Any Participant who voluntarily terminates
his or her payroll deduction authorization prior to the last business day of an
Option Period will be deemed to have canceled his or her Option.

SECTION 11.  TERMINATION OF EMPLOYMENT

     Except as otherwise provided in Section 12, upon the termination of a
Participant's employment with the Company for any reason, he or she will cease
to be a Participant, any Option held by him or her under the Plan will be deemed
canceled, the balance of his or her withholding account will be returned, and he
or she will have no further rights under the Plan.


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SECTION 12.  DEATH OF PARTICIPANT

     A Participant may elect that if death should occur during an Option Period
the balance, if any, of the Participant's withholding account at the time of
death will be applied at the end of the Period to the exercise of the
Participant's Option and the shares thereby purchased under the Option (plus any
balance remaining in the Participant's withholding account) will be delivered to
the Participant's designated beneficiary or beneficiaries.  If the Participant
has more than one designated beneficiary, the Company will determine the
allocation among them and its determination will be final and binding on all
persons.  For purposes of the Plan, a Participant's designated beneficiary(ies)
shall be (i) such person or persons as are treated as the Participant's
beneficiary(ies) for purposes of the Company group life insurance plan
applicable to the Participant, or (ii) in the absence of any beneficiary
determined under clause (i), the Participant's estate.

SECTION 13.  EQUAL RIGHTS; PARTICIPANT'S RIGHTS NOT TRANSFERABLE

     All Participants granted Options under the Plan with respect to any Option
Period will have the same rights and privileges.  Each Participant's rights and
privileges under any Option granted under the Plan will be exercisable during
the Participant's lifetime only by him or her and except as provided at Section
12 above may not be sold, pledged, assigned, or transferred in any manner.  In
the event any Participant violates or attempts to violate the terms of this
Section, any Options held by him or her may be terminated by the Company and,
upon return to the Participant of the balance of his or her withholding account,
all of the Participant's rights under the Plan will terminate.

SECTION 14.  EMPLOYMENT RIGHTS

     Nothing contained in the provisions of the Plan will be construed as giving
to any Employee the right to be retained in the employ of the Company or as
interfering with the right of the Company to discharge any Employee at any time.

SECTION 15.  CHANGE IN CAPITALIZATION

     In the event of any change in the outstanding Stock of Mykrolis after [ ],
2001 by reason of a stock dividend, split-up, recapitalization, merger,
consolidation, reorganization, or other capital change, the aggregate number and
type of shares available under the Plan, the number and type of shares under
Options granted but not exercised, the maximum number and type of shares
purchasable under an Option, and the Option price will be appropriately
adjusted.

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SECTION 16.  ADMINISTRATION OF PLAN

     The Plan will be administered by the Board of Directors, which will have
the right to determine any questions which may arise regarding the
interpretation and application of the provisions of the Plan and to make,
administer, and interpret such rules and regulations as it will deem necessary
or advisable.  Reference to the Board of Directors in connection with its
administrative function under the Plan shall include its delegates.

SECTION 17.  AMENDMENT AND TERMINATION OF PLAN

     Mykrolis reserves the right at any time or times to amend the Plan to any
extent and in any manner it may deem advisable, by vote of the Board of
Directors; provided, that any amendment that would be treated as the adoption of
a new plan for purposes of Section 423 of the Code and the regulations
thereunder will have no force or effect unless approved by the shareholders of
Mykrolis within twelve months before or after its adoption.

     The Plan may be suspended or terminated at any time by the Board of
Directors.  In connection therewith, the Board of Directors may either cancel
outstanding Options or continue them and provide that they will be exercisable
either at the end of the applicable Option Period as determined under Section 4
above or on such earlier date as the Board of Directors may specify (in which
case such earlier date shall be treated as the last day of the applicable Option
Period).

SECTION 18.  APPROVAL OF SHAREHOLDERS

The Plan and the exercisability of Options granted hereunder will be subject to
the approval of the shareholders of Mykrolis obtained within twelve months
before or after the date the Plan is adopted by the Board of Directors.


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