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                                                                   EXHIBIT 10.15

                            SECURED PROMISSORY NOTE

$450,000,00                                                   February 1, 1999

     For Value Received, Dennis Raymond Riccio ("Employee") and Brenda Ellen
Riccio (together with Employee, collectively, "Maker"), hereby unconditionally
promise to pay to the order of Asyst Technologies, Inc., a California
corporation ("Lender"), at 48761 Kato Road, Fremont, California 94538,
Attention: Doug McCutcheon, or at such other place as the holder hereof may from
time to time designate in writing, in lawful money of the United States of
America and in immediately available funds, the principal amount of Four Hundred
Fifty Thousand Dollars ($450,000.00) together with interest accrued on the
unpaid principal (the "Loan") in accordance with the terms hereof.

     1.   Security. This Secured Promissory Note ("Note") is secured by a Second
Deed of Trust With Assignment of Rents dated of even date herewith, executed by
Maker in favor of Lender, as beneficiary (as the same may from time to time be
amended, modified or supplemented or restated, the "Deed of Trust"), granting a
security interest in certain real property located at 4210 Remillard Court,
Pleasanton, California, as more particularly described therein (the "Property").
Maker hereby represents and warrants that, as of the date hereof, (a) Maker is
or will be the sole and lawful fee owner of the Property, (b) the fair market
value of the Property, as determined by an M.A.I. appraiser reasonably
satisfactory to Lender, exceeds the aggregate amount of all indebtedness secured
by liens upon the Property and (c) the Deed of Trust creates a lien on the
Property second in priority only to a first lien of a Deed of Trust executed by
Maker in favor of James McDiarmid and Alice McDiarmid, husband and wife, as
joint tenants, securing a loan in the original principal amount of Two Hundred
Sixty-Eight Thousand Five Hundred and No/100ths Dollars ($268,500.00).

     2.   Principal Repayment. The entire outstanding principal balance of the
Loan shall be due and payable in full upon the earlier to occur of (a) January
31, 2004; (b) thirty (30) days after either the resignation by Employee of his
employment with Lender or the termination of his employment for Cause; or (c)
immediately upon the insolvency of Employee or Maker, including, but not limited
to, a bankruptcy or insolvency proceeding having been instituted by or against
Employee or Maker or a receiver being appointed for the property of Employee or
Maker, or if Employee or Maker makes an assignment for the benefit of creditors
(the "Maturity Date"). For purposes of this Note, "Cause" shall mean (i)
conviction of any felony or any crime involving moral turpitude or dishonesty;
(ii) participation in a fraud or act of dishonesty against Lender; (iii) willful
breach of Lender's policies; (iv) intentional damage to Lender's property; (v)
material breach of any employment agreements entered into with Lender, or any
other agreements with Lender, including, but not limited to, agreements
regarding confidentiality or proprietary information; (vi) engaging in or in any
manner participating in any activity which is competitive with or intentionally
injurious to Lender; (vii) commission of any fraud against Lender or use or
appropriation for Employee or Maker's personal use or benefit of any funds or
properties of Lender not authorized by Lender to be so used or appropriated; or
(viii) conduct by Employee which in the good faith and reasonable determination
of Lender demonstrates gross

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unfitness to serve. Physical (excluding self-inflicted incapacitation) or mental
disability shall not constitute Cause.

     3.   Interest Rate. Maker further promises to pay interest on the
outstanding principal amount hereof from the date hereof until payment in full,
which interest shall be payable at the rate of Four and 64/100 percent (4.64%)
per annum, compounded annually, or the maximum rate permissible by law (which
under the laws of the State of California shall be deemed to be the laws
relating to permissible rates of interest on commercial loans), whichever is
less (the "Interest Rate"). Interest shall be due and payable on the Maturity
Date and shall be calculated on the basis of a 360-day year for the actual
number of days elapsed.

     4.   Default Interest. If any amount payable hereunder shall not be paid
within five (5) days of the due date thereof, at the option of Lender the unpaid
principal balance shall immediately begin to accrue interest at a rate equal to
the Interest Rate plus one percent (1.0%) and Lender shall have all remedies
available to it by law as a creditor hereunder.

     5.   Application of Payments. Payment on this Note, if any, shall be
applied first to accrued interest, and thereafter to the outstanding principal
balance hereof. Any payment due hereunder shall be paid to Lender at the address
first set forth above, or at such other place as Lender may designate. Any
amount payable hereunder will be due and payable without set-off, deduction, or
counter-claim.

     6.   Prepayment. Maker may prepay the unpaid principal of this Note in
whole or in part, without penalty, at any time, upon the payment of all unpaid
interest accrued to the date of such prepayment.

     7.   Default and Remedies.

          (a)  Default. Each of the following events shall be an "Event of
Default" hereunder: (i) Maker fails to pay timely any of the principal amount
due under this Note on the date the same becomes due and payable or any accrued
interest or other amounts due under this Note on the date the same becomes due
and payable; (ii) the breach by Maker of any other covenant or agreement under
this Note, (iii) the default by Maker of its obligations under the Deed of Trust
or any other instrument evidencing or securing this Note, (iv) the default by
Maker of its obligations under any mortgage, deed of trust, encumbrance or lien
respecting the Property, which encumbrance is senior to the Deed of Trust, (v)
the death of Employee, (vi) the appointment of a receiver for any part of the
Property of, or an assignment for the benefit of creditors by, or the
commencement of any proceedings under any bankruptcy or insolvency laws by or
against any Maker or (vii) the transfer, directly or indirectly, of all or any
part of any interest in Maker or the Property, whether by sale, lease,
assignment, mortgage or otherwise, voluntarily or involuntarily.

          (b)  Remedies. Upon the occurrence of an Event of Default, Lender may,
with notice to Maker, declare the entire principal amount of this Note and any
amounts due thereon immediately due and payable and exercise any and all of the
remedies provided under the Deed of Trust or at law or in equity.

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     8.   Notice. All notices or other communications required or given
hereunder shall be in writing and shall be deemed effectively given when
presented personally or on the date of receipt (or refusal of delivery) if sent
by courier service or U.S. Mail (certified or registered, postage prepaid,
return receipt requested) to the parties at the addresses given below or such
other addresses as the parties may hereafter designate in writing. The date
shown on the courier's confirmation of delivery or return receipt shall be
conclusive as to the date of receipt.

          Maker:    4210 Remillard Court
                    Pleasanton, CA 94566

          Lender:   Asyst Technologies, Inc.
                    48761 Kato Road
                    Fremont, CA 94538
                    Attn: Doug McCutcheon

     9.   Maximum Legal Rate Of Interest. All agreements between Maker and
Lender, whether now existing or hereafter arising, are hereby limited so that in
no event shall the interest charged hereunder or agreed to be paid to Lender
exceed the maximum amount permissible under applicable law. Lender shall be
entitled to amortize, prorate and spread throughout the full term of this Note
all interest paid or payable so that the interest paid does not exceed the
maximum amount permitted by law. If Lender ever receives interest or anything
deemed interest in excess of the maximum lawful amount, an amount equal to the
excessive interest shall be applied to the reduction of the principal, and if it
exceeds the unpaid balance of principal hereof, such excess shall be refunded to
Maker. If interest otherwise payable to Lender would exceed the maximum lawful
amount, the interest payable shall be reduced to the maximum amount permitted
under applicable law. This section shall control all agreements between Maker
and Lender in connection with the indebtedness evidenced hereby.

     10.  Waiver. Maker, severally waives diligence, presentment, protest and
demand and also notice of protest, demand, dishonor, acceleration, intent to
accelerate, and nonpayment of this Note, and shall pay all costs of collection
when incurred, including, without limitation, reasonable attorneys' fees, costs
and other expenses. The right to plead any and all statutes of limitations as a
defense to any demands hereunder is hereby waived to the full extent permitted
by law.

     11.  Use Of Proceeds; Non-Transferable. The proceeds of the Loan may only
be used by Maker to purchase the Property as their principal residence. The
right of Maker to request and receive the Loan hereunder, as well as the other
benefits under this Note, shall not be assignable or otherwise transferable by
Maker.

     12.  Miscellaneous.

          (a)  Maker shall pay all costs, including, without limitation,
reasonable attorneys' fees and expenses incurred by Lender in collecting the
sums due hereunder or in connection with the release of any security for this
Note.

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          (b)  This Note may be modified only by a written agreement executed by
Maker and Lender.

          (c)  The terms of this Note shall inure to the benefit of and bind
Maker and Lender and their respective heirs, legal representatives and
successors and assigns.

          (d)  Time is of the essence with respect to all matters set forth in
this Note.

          (e)  If this Note is destroyed, lost or stolen, Maker will deliver a
new note to Lender on the same terms and conditions as this Note with a notation
of the unpaid principal in substitution of the prior Note. Lender shall furnish
to Maker reasonable evidence that the Note was destroyed, lost or stolen and any
security or indemnity that may be reasonably required by Maker in connection
with the replacement of this Note.

          (f)  If any provision of this Note shall be held to be invalid or
unenforceable, such determination shall not affect the remaining provisions of
this Note.

          (g)  If this Note is now, or hereinafter shall be, signed by more than
one party or person, it shall be the joint and several obligation of such
parties or persons and shall be binding upon such parties and upon their
respective successors and assigns.

          (h)  In the event of any litigation concerning this Note, the
prevailing party shall be entitled to a reasonable sum for attorneys' fees,
costs, and litigation expenses, whether or not such action is prosecuted to
judgment. "Prevailing Party" shall mean, without limitation, a party who agrees
to dismiss an action upon payment by the other party of sums allegedly due or
performance of the covenants allegedly breached, or who obtains substantially
the relief sought by that party. In the event that Lender is the Prevailing
Party, Lender shall also be entitled to reasonable costs associated with the
collection of the Loan.

     13.  Governing Law. This Note shall be governed by, and construed and
enforced in accordance with, the laws of the State of California, excluding
conflict of laws principles that would cause the application of laws of any
other jurisdiction .

In Witness Whereof, Maker has executed this Secured Promissory Note as of the
date and year first above written.



/s/ Dennis Raymond Riccio       /s/ Brenda Ellen Riccio
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Dennis Raymond Riccio           Brenda Ellen Riccio

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