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                                                                   Exhibit 10.19
                                 REVOLVING NOTE

$10,000,000.00                                                    August 9, 2002
                                                         Walla Walla, Washington

     FOR VALUE RECEIVED, the undersigned, KEY TECHNOLOGY, INC., an Oregon
corporation (the "Borrower"), hereby promises to pay to the order of BANNER
BANK, a Washington banking corporation (the "Lender") on the Revolving Maturity
Date the unpaid principal balance of all Revolving Loans made by Lender under
this Note, in a maximum amount not to exceed Ten Million Dollars ($10,000,000),
together with interest thereon from the date hereof until maturity at a per
annum rate equal to one percent (1%) above the Prime Rate (changing as such
Prime Rate changes); provided, however, that after the occurrence and during the
continuation of an Event of Default, interest shall accrue at a per annum rate
equal to three percent (3%) above the Prime Rate (changing as such Prime Rate
changes). Notwithstanding anything herein to the contrary, interest shall not
accrue at a rate in excess of the maximum rate permitted by applicable law.

     Borrower further agrees as follows:

     1.  All payments of principal and interest on this Note shall be made by
paying the same in United States Dollars and in immediately available funds to
Lender in accordance with wire transfer instructions as may be provided to
Borrower from time to time, at its main office, Walla Walla, Washington, not
later than 2:00 p.m. (Walla Walla time) on the date on which such payment shall
become due. If such payment is received after 2:00 p.m., then it will be deemed
received on the next Business Day.

     2.  On each day that the aggregate outstanding principal balance of all
Revolving Loans exceeds the Borrowing Base, Borrower shall repay Revolving Loans
in such an amount as is necessary to reduce such aggregate outstanding principal
balance to an amount equal to or less than the Borrowing Base.

     3.  Accrued but unpaid interest on each Revolving Loan shall be paid in
arrears on the first Business Day of each calendar month and at the Revolving
Maturity Date. Accrued interest on each Revolving Loan shall be payable on
demand after the occurrence of an Event of Default.

     4.  This Note is issued under and is subject to the terms of that certain
Loan Agreement dated as of August 9, 2002, by and between Borrower and Lender
(as amended from time to time, the "Loan Agreement"). Capitalized terms not
defined herein have the meanings set forth in the Loan Agreement.

     5.  It is expressly provided that if any of the Events of Default described
in Section 7.1(g) or Section 7.1(h) of the Loan Agreement shall occur, the
entire unpaid balance of the principal and interest hereunder shall be
immediately due and payable in accordance with the terms of the Loan Agreement.
It is also expressly provided that upon the occurrence of any other

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Event of Default, the entire remaining unpaid balance of the principal and
interest may be declared by Lender to be immediately due and payable in
accordance with the terms of the Loan Agreement.

     6.  Borrower may repay Revolving Loans at any time without penalty or
premium.

     7.  The unpaid principal balance of the Revolving Loans made hereunder
shall be the total amount advanced hereunder, less the amount of the principal
payments made hereon. This Note is given to avoid the execution of an individual
note for each Revolving Loan made by Lender to Borrower. This Note evidences a
revolving credit and up to the Revolving Commitment Amount and during the
Revolving Commitment Period, Borrower may pay, prepay and reborrow. Lender is
hereby authorized to record the date and amount of each Revolving Loan it makes
hereunder and the date and amount of each payment of principal and interest
thereon on a schedule annexed hereto and constituting a part of this Note or
maintained in connection herewith. Any such recordation by Lender shall
constitute prima facie evidence of the accuracy of the information so recorded;
provided, however, that the failure to make any such recordation or any error in
any such recordation shall not affect the obligations of Borrower hereunder.

     8.  Each maker, surety, guarantor and endorser of this Note expressly
waives all notices, demands for payment, presentations for payment, notices of
intention to accelerate the maturity, protest and notice of protest.

     9.  In the event this Note is placed in the hands of an attorney for
collection, or suit is brought on the same, or the same is collected through
bankruptcy or other judicial proceedings, Borrower agrees and promises to pay
reasonable attorneys' fees and collection costs, including all out-of-pocket
expenses and the allocated costs and disbursements of internal counsel, incurred
by Lender.

     10. This Note has been executed and delivered in and shall be governed by
and construed in accordance with the laws of the State of Washington, excluding
its conflict of laws rules. Borrower hereby irrevocably submits to the
non-exclusive jurisdiction of any state or federal court sitting in the City of
Walla Walla, Walla Walla County, Washington, in any action or proceeding brought
to enforce or otherwise arising out of or relating to this Note and hereby
waives any objection to venue in any such court and any claim that such forum is
an inconvenient forum.

     BORROWER:                            KEY TECHNOLOGY, INC., an Oregon
                                          corporation


                                          By  /s/ Ted R. Sharp
                                              ----------------------------------
                                          Its C.F.O.
                                              ----------------------------------

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