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                                                                    Exhibit 10.7


                               MICRION CORPORATION

                              AMENDED AND RESTATED

                             1994 OMNIBUS STOCK PLAN

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         1.  Purpose. This Micrion Corporation Amended and Restated 1994 Omnibus
Stock Plan (the "Plan") is intended to provide incentives (a) to the officers
and other employees of Micrion Corporation (the "Company"), its parent (if any)
and any present or future subsidiaries of the Company (collectively, "Related
Corporations") by providing them with opportunities to purchase stock in the
Company pursuant to options which qualify as "incentive stock options" under
Section 422 of the Internal Revenue Code of 1986, as amended (the "Code"),
granted hereunder ("ISO" or "ISOs"); (b) to directors, officers, employees and
consultants of the Company and Related Corporations by providing them with
opportunities to purchase stock in the Company pursuant to options granted
hereunder which do not qualify as ISOs ("Non-Qualified Option" or "Non-Qualified
Options"); and (c) to directors, officers, employees and consultants of the
Company and Related Corporations by providing them with opportunities to make
direct purchases of restricted stock in the Company ("Restricted Stock"). Both
ISOs and Non-Qualified Options are referred to hereafter individually as an
"Option" and collectively as "Options." As used herein, the terms "parent" and
"subsidiary" mean "parent corporation" and "subsidiary corporation" as those
terms are defined in Section 424 of the Code.

         2.  Administration of the Plan. (a) The Plan shall be administered by
the Board of Directors of the Company (the "Board"). The Board may appoint a
Compensation Committee (the "Committee") of two or more of its members to
administer the Plan. In the event the Company registers any class of any equity
security pursuant to Section 12 of the Securities Exchange Act of 1934, as
amended (the "Exchange Act"), each member of the Committee shall be a
"non-employee director" as defined in Rule 16b-3 under the Exchange Act. Subject
to ratification of the grant of each Option or Restricted Stock by the Board (if
so required by applicable state law), and subject to the terms of the Plan, the
Committee, if so appointed, shall have the authority to (i) determine the
employees of the Company and Related Corporations (from among the class of
employees eligible under paragraph 3 to receive ISOs) to whom ISOs may be
granted, and to determine (from among the class of individuals and entities
eligible under paragraph 3 to receive Non- Qualified Options and Restricted
Stock) to whom Non-Qualified Options or Restricted Stock may be granted; (ii)
determine the time or times at which Options or Restricted Stock may be granted;
(iii) determine the option price of shares subject to each Option, which

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price with respect to ISOs shall not be less than the minimum specified in
paragraph 6, and the purchase price of Restricted Stock; (iv) determine whether
each Option granted shall be an ISO or a Non-Qualified Option; (v) determine
(subject to paragraph 7) the time or times when each Option shall become
exercisable and the duration of the exercise period; (vi) determine whether
restrictions such as repurchase options are to be imposed on shares subject to
Options and to Restricted Stock, and the nature of such restrictions, if any;
and (vii) interpret the Plan and prescribe and rescind rules and regulations
relating to it. If the Committee determines to issue a Non-Qualified Option, it
shall take whatever actions it deems necessary, under Section 422 of the Code
and the regulations promulgated thereunder, to ensure that such Option is not
treated as an ISO. The interpretation and construction by the Committee of any
provisions of the Plan or of any Option or authorization or agreement for
Restricted Stock granted under it shall be final unless otherwise determined by
the Board. The Committee may from time to time adopt such rules and regulations
for carrying out the Plan as it may deem best. No member of the Board or the
Committee shall be liable for any action or determination made in good faith
with respect to the Plan or any Option or Restricted Stock granted under it.

         (b)  The Committee may select one of its members as its chairman, and
shall hold meetings at such time and places as it may determine. Acts by a
majority of the Committee, or acts reduced to or approved in writing by a
majority of the members of the Committee, shall be the valid acts of the
Committee. All references in the Plan to the Committee shall mean the Board if
there is no Committee so appointed. From time to time the Board may increase the
size of the Committee and appoint additional members thereof, remove members
(with or without cause), and appoint new members in substitution therefor, fill
vacancies however caused, or remove all members of the Committee and thereafter
directly administer the Plan.

         3.  Eligible Employees and Others. ISOs may be granted to any officer
or other employee of the Company or any Related Corporation. Those directors of
the Company who are not employees may not be granted ISOs under the Plan.
Non-Qualified Options and Restricted Stock may be granted to any director
(whether or not an employee), officer, employee or consultant of the Company or
any Related Corporation. The Committee may take into consideration an optionee's
individual circumstances in determining whether to grant an ISO or a
Non-Qualified Option or Restricted Stock. Granting of any Option or Restricted
Stock to any individual or entity shall neither entitle that individual or
entity to, nor disqualify him from, participation in any other grant of Options
or Restricted Stock.

         4.  Stock. The stock subject to Options and Restricted Stock shall be
authorized but unissued shares of Common Stock of the Company, no par value per
share (the "Common Stock"), or shares of


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Common Stock re-acquired by the Company in any manner. The aggregate number of
shares which may be issued pursuant to the Plan is 1,000,000, subject to
adjustment as provided in paragraph 13. Any such shares may be issued as ISOs,
Non-Qualified Options or Restricted Stock so long as the aggregate number of
shares so issued does not exceed such number, as adjusted. If any Option
granted under the Plan shall expire or terminate for any reason without having
been exercised in full or shall cease for any reason to be exercisable in whole
or in part, or if any Restricted Stock shall be reacquired by the Company by
exercise of its repurchase option, the shares subject to such expired or
terminated Option and reacquired shares of Restricted Stock shall again be
available for grants of Options or Restricted Stock under the Plan.

         5.  Grants Under the Plan. Options or Restricted Stock may be granted
under the Plan at any time prior to September 5, 2007. Any such grants of ISOs
shall be subject to the receipt, within 12 months of September 5, 1997, of the
approval of Stockholders as provided in paragraph 17. The date of grant of an
Option under the Plan will be the date specified by the Committee at the time
it awards the Option; provided, however, that such date shall not be prior to
the date of award. The Committee shall have the right, with the consent of the
optionee, to convert an ISO granted under the Plan to a Non-Qualified Option
pursuant to paragraph 15.

         6.  Minimum Option Price. (a) The price per share specified in the
agreement relating to each ISO granted under the Plan shall not be less than the
fair market value per share of Common Stock on the date of such grant. In the
case of an ISO to be granted to an employee owning stock possessing more than
ten percent of the total combined voting power of all classes of stock of the
Company or any Related Corporation, the price per share specified in the
agreement relating to such ISO shall not be less than 110 percent of the fair
market value of Common Stock on the date of grant.

         (b)  In no event shall the aggregate fair market value (determined at
the time the option is granted) of Common Stock for which ISOs granted to any
employee are exercisable for the first time by such employee during any calendar
year (under all stock option plans of the Company and any Related Corporation)
exceed $100,000.

         (c)  The price per share specified in the agreement related to each
Non-Qualified Option granted under the Plan shall not be less than eighty-five
percent (85%) of the fair market value of a share of Common Stock on the date of
such grant.

         (d)  If, at the time an Option is granted under the Plan, the Company's
Common Stock is publicly traded, "fair market value" shall be determined as of
the last business day for which the prices or quotes discussed in this sentence
are available prior to the date such Option is granted and shall mean (i) the
average (on that date) of the high and low prices of the Common Stock on the


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principal national securities exchange on which the Common Stock is traded, if
such stock is then traded on a national securities exchange; or (ii) the last
reported sale price (on that date) of the Common Stock on the NASDAQ National
Market System, if the Common Stock is not then traded on a national securities
exchange; or (iii) the closing bid price (or average of bid prices) last quoted
(on that date) by an established quotation service for over-the-counter
securities, if the Common Stock is not reported on the NASDAQ National Market
System or on a national securities exchange. However, if the Common Stock is not
publicly traded at the time an Option is granted under the Plan, "fair market
value" shall be deemed to be the fair value of the Common Stock as determined by
the Committee after taking into consideration all factors which it deems
appropriate, including, without limitation, recent sale and offer prices of the
Common Stock in private transactions negotiated at arm's length.

         7.  Option Duration. Subject to earlier termination as provided in
paragraphs 9 and 10, each Option shall expire on the date specified by the
Committee, but not more than ten years from the date of grant or, in the case of
ISOs granted to an employee owning stock possessing more than ten percent of the
total combined voting power of all classes of stock of the Company or any
Related Corporation, not more than five years from date of grant. Subject to
earlier termination as provided in paragraphs 9 and 10, the term of each ISO
shall be the term set forth in the original instrument granting such ISO, except
with respect to any part of such ISO that is converted into a Non-Qualified
Option pursuant to paragraph 15.

         8.  Exercise of Option. Subject to the provisions of paragraphs 9
through 12, each Option granted under the Plan shall be exercisable as follows:

         (a)  The Option shall either be fully exercisable on the date of grant
or shall become exercisable thereafter in such installments as the Committee may
specify.

         (b)  Once an installment becomes exercisable it shall remain
exercisable until expiration or termination of the Option, unless otherwise
specified by the Committee.

         (c)  Each Option or installment may be exercised at any time or from
time to time, in whole or in part, for up to the total number of shares with
respect to which it is then exercisable.

         (d)  The Committee shall have the right to accelerate the date of
exercise of any installment; provided that the Committee shall not accelerate
the exercise date of any installment of any Option granted to any employee as an
ISO (and not previously converted into a Non-Qualified Option pursuant to
paragraph 15) if such acceleration would violate the annual vesting limitation
contained in Section 422(d) of the Code which provides generally that the
aggregate fair market value (determined at the time the option is


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granted) of the stock with respect to which ISOs granted to any employee are
exercisable for the first time by such employee during any calendar year (under
all plans of the Company and any Related Corporation) shall not exceed $100,000.

         9.  Termination of Employment. If an ISO optionee ceases to be employed
by the Company or any Related Corporation other than by reason of death or
disability as provided in paragraph 10, no further installments of his ISOs
shall become exercisable, and his ISOs shall terminate after the passage of 60
days from the date of termination of his employment, but in no event later than
on their specified expiration dates except to the extent that such ISOs (or
unexercised installments thereof) have been converted into Non-Qualified
Options pursuant to paragraph 15. Leave of absence with the written approval of
the Committee shall not be considered an interruption of employment under the
Plan, provided that such written approval contractually obligates the Company or
any Related Corporation to continue the employment of the employee after the
approved period of absence. Employment shall also be considered as continuing
uninterrupted during any other bona fide leave of absence (such as those
attributable to illness, military obligations or governmental service) provided
that the period of such leave does not exceed 90 days or, if longer, any period
during which such optionee's right to reemployment is guaranteed by statute.
Nothing in the Plan shall be deemed to give any grantee of any Option or
Restricted Stock the right to be retained in employment or other service by the
Company or any Related Corporation for any period of time. ISOs granted under
the Plan shall not be affected by any change of employment within or among the
Company and Related Corporations, so long as the optionee continues to be an
employee of the Company or any Related Corporation. In granting any
Non-Qualified Option, the Committee may specify that such Non-Qualified Option
shall be subject to the restrictions set forth herein with respect to ISOs, or
to such other termination or cancellation provisions as the Committee may
determine.

         10. Death; Disability; Dissolution. If an optionee ceases to be
employed by the Company and all Related Corporations by reason of his death, any
Option of his may be exercised, to the extent of the number of shares with
respect to which he could have exercised it on the date of his death, by his
estate, personal representative or beneficiary who has acquired the Option by
will or by the laws of descent and distribution, at any time prior to the
earlier of the Option's specified expiration date or 180 days from the date of
the optionee's death.

         If an optionee ceases to be employed by the Company and all Related
Corporations by reason of his disability, he shall have the right to exercise
any Option held by him on the date of termination of employment, to the extent
of the number of shares with respect to which he could have exercised it on that
date, at any time prior to the earlier of the Option's specified expiration date
or 180


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days from the date of the termination of the optionee's employment. For the
purposes of the Plan, the term "disability" shall have the meaning assigned to
it in Section 22(e)(3) of the Code or any successor statute.

         In the case of a partnership, corporation or other entity holding a
Non-Qualified Option, if such entity is dissolved, liquidated, becomes insolvent
or enters into a merger or acquisition with respect to which such optionee is
not the surviving entity, such Option shall terminate immediately.

         11. Assignability. Subject to the provisions of this Section 11, (a) no
Option shall be transferable otherwise than by will, by the laws of descent and
distribution, or by operation of a "qualified domestic relations order," as that
term is defined in the Code, and (b) during the lifetime of the Optionee, rights
under the Option may be exercised only by the Optionee, the Optionee's guardian
or legal representative, or by the assignee of the Option under such a
"qualified domestic relations order." Notwithstanding the foregoing, the
Committee may provide for greater transferability in the case of any Option
including, without limitation, transfer to one or more members of the Optionee's
family. Unless otherwise provided by the Committee, the conditions and criteria
governing the exercise or payment of such an Option (by way of example
accelerated vesting upon death or disability or the attainment of performance
goals applicable to the Optionee) shall, following any permitted transfer,
continue to be determined by reference to the Optionee and not the transferee.
In no event shall ISOs awarded under the Plan be transferable other than as
permitted under the rules prescribed in or under the Code for incentive stock
options. An award that is intended to be exempt under Rule 16b-3 under the
Exchange Act or any successor rule, or that is intended to qualify for the
performance-based exception under Section 162(m) of the Code, shall be
transferable only to the extent consistent with such exemption or qualification.

         12. Terms and Conditions of Options. Options shall be evidenced by
instruments (which need not be identical) in such forms as the Committee may
from time to time approve. Such instruments shall conform to the terms and
conditions set forth in paragraphs 6 through 11 hereof and may contain such
other provisions as the Committee deems advisable which are not inconsistent
with the Plan, including transfer and repurchase restrictions applicable to
shares of Common Stock issuable upon exercise of Options. The Committee may from
time to time confer authority and responsibility on one or more of its own
members and/or one or more officers of the Company to execute and deliver such
instruments. The proper officers of the Company are authorized and directed to
take any and all action necessary or advisable from time to time to carry out
the terms of such instruments.


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         13. Adjustments. Upon the happening of any of the following described
events, an optionee's rights with respect to Options granted to him hereunder
shall be adjusted as hereinafter provided:

         (a)  In the event shares of Common Stock shall be sub-divided or
combined into a greater or smaller number of shares or if, upon a merger,
consolidation, reorganization, split-up, liquidation, combination,
recapitalization or the like of the Company, the shares of Common Stock shall be
exchanged for other securities of the Company or of another corporation, each
optionee shall be entitled, subject to the conditions herein stated, to purchase
such number of shares of common stock or amount of other securities of the
Company or such other corporation as were exchangeable for the number of shares
of Common Stock which such optionee would have been entitled to purchase except
for such action, and appropriate adjustments shall be made in the purchase price
per share to reflect such subdivision, combination, or exchange.

         (b)  In the event the Company shall issue any of its shares as a stock
dividend upon or with respect to the shares of stock of the class which shall at
the time be subject to option hereunder, each optionee upon exercising an Option
shall be entitled to receive (for the purchase price paid upon such exercise)
the shares as to which he is exercising his Option and, in addition thereto (at
no additional cost), such number of shares of the class or classes in which such
stock dividend or dividends were declared or paid, and such amount of cash in
lieu of fractional shares, as he would have received if he had been the holder
of the shares as to which he is exercising his Option at all times between the
date of grant of such Option and the date of its exercise.

         (c)  Notwithstanding the foregoing, any adjustments made pursuant to
subparagraph (a) or (b) shall be made only after the Committee, after consulting
with counsel for the Company, determines whether such adjustments with respect
to ISOs will constitute a "modification" of such ISOs as that term is defined in
Section 424 of the Code, or cause any adverse tax consequences for the holders
of such ISOs. No adjustments shall be made for dividends paid in cash or in
property other than securities of the Company.

         (d)  No fractional shares shall actually be issued under the Plan. Any
fractional shares which, but for this subparagraph (d), would have been issued
to an optionee pursuant to an Option, shall be deemed to have been issued and
immediately sold to the Company for their fair market value, and the optionee
shall receive from the Company cash in lieu of such fractional shares.

         (e)  Upon the happening of any of the foregoing events described in
subparagraphs (a) or (b) above, the class and aggregate number of shares set
forth in paragraph 4 hereof which are subject to Options which previously have
been or subsequently may be granted under the Plan shall also be appropriately
adjusted


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to reflect the events specified in such subparagraphs. The Committee shall
determine the specific adjustments to be made under this paragraph 13, and
subject to paragraph 2, its determination shall be conclusive.

         14. Means of Exercising Options. An Option (or any part or installment
thereof) shall be exercised by giving written notice to the Company at its
principal office address. Such notice shall identify the Option being exercised
and specify the number of shares as to which such Option is being exercised,
accompanied by full payment of the purchase price therefor either (i) in United
States dollars in cash or by check, or (ii) at the discretion of the Committee,
through delivery of shares of Common Stock having fair market value equal as of
the date of the exercise to the cash exercise price of the Option, or (iii) at
the discretion of the Committee, by delivery of the optionee's personal recourse
note bearing interest payable not less than annually at no less than 100% of the
lowest applicable Federal rate, as defined in Section 1274(d) of the Code, or
(iv) at the discretion of the Committee, by any combination of (i), (ii) and
(iii) above. If the Committee exercises its discretion to permit payment of the
exercise price of an ISO by means of the methods set forth in clauses (ii) or
(iii) of the preceding sentence, such discretion shall be exercised in writing
at the time of the grant of the ISO in question. The holder of an Option shall
not have the rights of a shareholder with respect to the shares covered by his
Option until the date of issuance of a stock certificate to him for such shares.
Except as expressly provided above in paragraph 13 with respect to change in
capitalization and stock dividends, no adjustment shall be made for dividends or
similar rights for which the record date is before the date such stock
certificates are issued.

         15. Conversion of ISOs into Non-Qualified Options: Termination of ISOs.
The Committee, at the written request of any optionee, may in its discretion
take such actions as may be necessary to convert such optionee's ISOs (or any
installments or portions of installments thereof) that have not been exercised
on the date of conversion into Non-Qualified Options at any time prior to the
expiration of such ISOs, regardless of whether the optionee is an employee of
the Company or a Related Corporation at the time of such conversion. Such
actions may include, but not be limited to, extending the exercise period or
reducing the exercise price of the appropriate installments of such Options. At
the time of such conversion, the Committee (with the consent of the optionee)
may impose such conditions on the exercise of the resulting Non-Qualified
Options as the Committee in its discretion may determine, provided that such
conditions shall not be inconsistent with the Plan. Nothing in the Plan shall be
deemed to give any optionee the right to have such optionee's ISOs converted
into Non-Qualified Options, and no such conversion shall occur until and unless
the Committee takes appropriate action. The Committee, with the consent of the
optionee, may also terminate any portion of any ISO that has not been exercised
at the time of such termination.


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         16. Restricted Stock. Each grant of Restricted Stock under the Plan
shall be evidenced by an instrument (a "Restricted Stock Agreement") in such
form as the Committee shall prescribe from time to time in accordance with the
Plan and shall comply with the following terms and conditions, and with such
other terms and conditions as the Committee, in its discretion, shall establish:

         (a)  The Committee shall determine the number of shares of Common Stock
to be issued to an eligible person pursuant to the grant of Restricted Stock,
and the extent, if any, to which they shall be issued in exchange for cash,
other consideration, or both.

         (b)  Shares issued pursuant to a grant of Restricted Stock may not be
sold, assigned, transferred, pledged or otherwise disposed of, except by will or
the laws of descent and distribution, or as otherwise determined by the
Committee in the Restricted Stock Agreement, for such period as the Committee
shall determine, from the date on which the Restricted Stock is granted (the
"Restricted Period"). The Company will have the option to repurchase the Common
Stock at such price as the Committee shall have fixed in the Restricted Stock
Agreement which option will be exercisable (i) if the participant's continuous
employment or performance of services for the Company and the Related
Corporations shall terminate prior to the expiration of the Restricted Period,
(ii) if, on or prior to the expiration of the Restricted Period or the earlier
lapse of such repurchase option, the participant has not paid to the Company an
amount equal to any federal, state, local or foreign income or other taxes which
the Company determines is required to be withheld in respect of such Restricted
Stock, or (iii) under such other circumstances as determined by the Committee in
its discretion. Such repurchase option shall be exercisable on such terms, in
such manner and during such period as shall be determined by the Committee in
the Restricted Stock Agreement. Each certificate for shares issued as Restricted
Stock shall bear an appropriate legend referring to the foregoing repurchase
option and other restrictions; shall be deposited by the stockholder with the
Company, together with a stock power endorsed in blank; or shall be evidenced in
such other manner permitted by applicable law as determined by the Committee in
its discretion. Any attempt to dispose of any such shares in contravention of
the foregoing repurchase option and other restrictions shall be null and void
and without effect. If shares issued as Restricted Stock shall be repurchased
pursuant to the repurchase option described above, the stockholder, or in the
event of his death, his estate, personal representative, or beneficiary who has
acquired the Option by will or by the laws of descent and distribution, shall
forthwith deliver to the Secretary of the Company the certificates for the
shares, accompanied by such instrument of transfer, if any, as may reasonably be
required by the Secretary of the Company. If the repurchase option described
above is not exercised by the Company, such repurchase option and the
restrictions imposed pursuant to the first sentence of this subparagraph (b)
shall terminate and be of no further force and effect.


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         (c)  If a person who has been in continuous employment or performance
of services for the Company or a Related Corporation since the date on which
Restricted Stock was granted to him shall, while in such employment or
performance of services, die, or terminate such employment or performance of
services by reason of disability or by reason of early, normal or deferred
retirement under an approved retirement program of the Company or a Related
Corporation (or such other plan or arrangement as may be approved by the
Committee in its discretion, for this purpose) and any of such events shall
occur after the date on which the Restricted Stock was granted to him and prior
to the end of the Restricted Period, the Committee may determine to cancel the
repurchase option (and any and all other restrictions) on any or all of the
shares of Restricted Stock; and the repurchase option shall become exercisable
at such time as to the remaining shares, if any.

         17. Term and Amendment of Plan. This Plan shall expire on September 5,
2007 (except as to Options and Restricted Stock outstanding on that date). The
Board may terminate or amend the Plan in any respect at any time. No amendment
of the Plan shall adversely affect in a material manner any right of any
Optionee or purchaser of Restricted Stock without his written consent, under any
Option or Restricted Stock previously granted to him.

         18. Application of Funds. The proceeds received by the Company from the
sale of shares pursuant to Options and Restricted Stock authorized under the
Plan shall be used for general corporate purposes.

         19. Governmental Regulation. The Company's obligation to sell and
deliver shares of the Common Stock under this Plan is subject to the approval of
any governmental authority required in connection with the authorization,
issuance or sale of such shares.

         20. Withholding of Additional Income Taxes. The Company, in accordance
with the Code, may, upon exercise of a Non-Qualified Option or the purchase of
Common Stock for less than its fair market value or the lapse of restrictions on
Restricted Stock or the making of a Disqualifying Disposition (as defined in
paragraph 21) require the employee to pay additional withholding taxes in
respect of the amount that is considered compensation includible in such
person's gross income.

         21. Notice to Company of Disqualifying Disposition. Each employee who
receives ISOs shall agree to notify the Company in writing immediately after the
employee makes a disqualifying disposition of any Common Stock received pursuant
to the exercise of an ISO (a "Disqualifying Disposition"). Disqualifying
Disposition means any disposition (including any sale) of such stock before the
later of (a) two years after the employee was granted the ISO under which he
acquired such stock, or (b) one year after the employee acquired such stock by
exercising such ISO. If the employee has died before such stock is sold, these
holding


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period requirements do not apply and no Disqualifying Disposition will
thereafter occur.

         22. Governing Laws; Construction. The validity and construction of the
Plan and the instruments evidencing Options and Restricted Stock shall be
governed by the laws of The Commonwealth of Massachusetts. In construing this
Plan, the singular shall include the plural and the masculine gender shall
include the feminine and neuter, unless the context otherwise requires.


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