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                                                                   Exhibit 10.32


                                 PROMISSORY NOTE


$8,000,000.00
                                                           Boston, Massachusetts
                                                                   July 31, 1997

         FOR VALUE RECEIVED, the undersigned Micrion Corporation, a
Massachusetts corporation (the "Borrower"), hereby promises to pay to the order
of FLEET NATIONAL BANK (the "Bank") the principal amount of Eight Million and
00/100 ($8,000,000.00) Dollars ("Principal"), with interest, at the rate
hereinafter set forth, on the daily balance of all unpaid Principal, from the
date hereof until payment in full of all Principal and interest hereunder. As
used herein, the "Letter Agreement" will be deemed to mean that certain Letter
Agreement of even date herewith between the Bank and the Borrower, as same may
be from time to time amended.

         Interest on all unpaid Principal shall be due and payable monthly in
arrears, on the first day of each month, commencing on the first such date after
the date hereof and continuing hereof and on the first day of each month
thereafter and on the date of payment of this note in full, at a fluctuating
rate per annum (computed on the basis of a year of three hundred sixty (360)
days for the actual number of days elapsed) which shall at all times be equal to
the sum of (i) one and one-half percent (1.5%) per annum plus (ii) the Prime
Rate, as in effect from time to time (but in no event in excess of the maximum
rate permitted by then applicable law), with a change in the aforesaid rate of
interest to become effective on the same day on which any change in the Prime
Rate is effective. Overdue Principal and, to the extent permitted by law,
overdue interest shall bear interest at a fluctuating rate per annum which at
all times shall be equal to the sum of (i) two (2%) percent per annum plus (ii)
the per annum rate otherwise payable under this note with respect to the
Principal which is overdue (or as to which such interest is overdue) (but in no
event in excess of the maximum rate permitted by then applicable law),
compounded monthly and payable on demand. As used herein, "Prime Rate" means
that rate of interest per annum announced by the Bank from time to time as its
prime rate, it being understood that such rate is merely a reference rate, not
necessarily the lowest, which serves as the basis upon which effective rates of
interest are calculated for obligations making reference thereto. If the entire
amount of any required Principal and/or interest is not paid within ten (10)
days after the same is due, the Borrower shall pay to the Bank a late fee equal
to five percent (5%) of the required payment.

         All outstanding Principal shall be repaid by the Borrower to the Bank
in 8 equal consecutive quarterly installments (each in the amount of
$1,000,000), such an installment to be paid on each of September 30, 1998,
December 31, 1998, March 31, 1999, June 30, 1999, September 30, 1999, December
31, 1999, March 31, 2000 and June 30, 2000, with the then remaining balance of
Principal and all interest accrued but unpaid thereon being due and payable in
full in any event on June 30, 2000. The Borrower may at any time and from time
to time prepay all or any portion of any Term Loan (as defined in the Letter
Agreement), but only in the manner, and (under certain circumstances) with the
additional payments, provided for in the Letter Agreement. Each Principal
prepayment shall be accompanied by payment of all interest 
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on this note accrued but unpaid to the date of payment. Any partial prepayment
of Principal will be applied against Principal installments in inverse order of
normal maturity.

         Payments of both Principal and interest shall be made, in immediately
available funds, at the office of the Bank located at 75 State Street, Boston,
Massachusetts 02109, or at such other address as the Bank may from time to time
designate.

         The undersigned Borrower irrevocably authorizes the Bank to make or
cause to be made, on a schedule attached to this note or on the books of the
Bank, at or following the time of receiving any payment of Principal, an
appropriate notation reflecting such transaction and the then aggregate unpaid
balance of Principal. Failure of the Bank to make any such notation shall not,
however, affect any obligation of the Borrower hereunder or under the Letter
Agreement. The unpaid Principal amount of this note, as recorded by the Bank
from time to time on such schedule or on such books, shall constitute
presumptive evidence of the unpaid principal amount of the Term Loan.

         The Borrower hereby (a) waives notice of and consents to any and all
advances, settlements, compromises, favors and indulgences (including, without
limitation, any extension or postponement of the time for payment), any and all
receipts, substitutions, additions, exchanges and releases of collateral, and
any and all additions, substitutions and releases of any person primarily or
secondarily liable, (b) waives presentment, demand, notice, protest and all
other demands and notices generally in connection with the delivery, acceptance,
performance, default or enforcement of or under this note, and (c) agrees to
pay, to the extent permitted by law, all costs and expenses, including, without
limitation, reasonable attorneys' fees, incurred or paid by the Bank in
enforcing this note and any collateral or security therefor, all whether or not
litigation is commenced.

         This note is the Term Note referred to in the Letter Agreement and is
entitled to the benefits of the Security Agreement (as defined in the Letter
Agreement). This note is subject to prepayment as set forth in the Letter
Agreement (which may require the making of certain additional payments, as
provided for in the Letter Agreement). The maturity of this note may be
accelerated upon the occurrence of an Event of Default, as provided in the
Letter Agreement.

         Executed, as an instrument under seal, as of the day and year first
above written.


CORPORATE SEAL                               MICRION CORPORATION

ATTEST:


/s/ N.P. Economou                            By: /s/ David M. Hunter
----------------------------                     -----------------------------
President & C.E.O                                Name: David M. Hunter
                                                 Title: Vice President, Finance
                                                        and Administration

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