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                                                                     EXHIBIT 4.3

                       FORM OF CERTIFICATE OF DESIGNATION
                      SERIES C CONVERTIBLE PREFERRED STOCK

                              KEY TECHNOLOGY, INC.


                Key Technology, Inc., an Oregon corporation (the "Corporation"),
certifies that pursuant to the authority contained in Article II of its Restated
Articles of Incorporation, and in accordance with the provisions of Section
60.134 of the Oregon Revised Statutes, its Board of Directors has adopted the
following resolution creating a series of its $20.00 par value Preferred Stock:

                RESOLVED, that, pursuant to authority conferred upon the Board
of Directors by the Articles of Incorporation of the Corporation, the Board of
Directors hereby authorizes the issuance of Series C Convertible Preferred Stock
of the Corporation and hereby designates, pursuant to Section 60.134 of the
Oregon Revised Statutes, the rights, preferences, privileges, restrictions and
other matters relating to such Series C Preferred Stock as follows

        1.      DESIGNATION AND AMOUNT.

                One Hundred Nineteen Thousand , One Hundred Six (119,106) shares
of the Corporation's authorized Preferred Stock are hereby designated as the
Series C Convertible Preferred Stock (the "Series C Preferred Stock").

        2.      DIVIDENDS.

                No dividends shall be declared and set aside for any shares of
the Series C Preferred Stock except in the event that the Board of Directors of
the Corporation shall declare a dividend payable upon the then outstanding
shares of the Common Stock of the Corporation, in which event the holders of the
Series C Preferred Stock shall be entitled to the amount of dividends per share
of Series C Preferred Stock as would be declared payable on the largest number
of whole shares of Common Stock into which each share of Series C Preferred
Stock held by each holder thereof could be converted pursuant to the provisions
of Section 5 hereof (such number determined as of the record date for the
determination of holders of Common Stock entitled to receive such dividend).

        3.      LIQUIDATION, DISSOLUTION OR WINDING UP

                3.1 PREFERENCE. In the event of any liquidation, dissolution or
winding up of the Corporation, whether voluntary or involuntary, holders of each
share of Series C Preferred Stock shall be entitled to be paid first out of the
assets of the Corporation available for distribution to holders of the
Corporation's capital stock of all classes (whether such assets are capital,
surplus or earnings) before any sums shall be paid or any assets distributed
among the holders of Common Stock, an amount equal to $20 per share of Series C
Preferred Stock plus an amount equal to all accrued and unpaid dividends
thereon, if any, computed up to and including



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the date full payment shall be tendered to the holders of the Series C Preferred
Stock with respect to such liquidation, dissolution or winding up.

                If the assets of the Corporation shall be insufficient to permit
the payment in full to holders of the Series C Preferred Stock of the amount
thus distributable, then the entire assets of the Corporation available for such
distribution shall be distributed ratably among the holders of the Series C
Preferred Stock.

                3.2 DISTRIBUTIONS OTHER THAN CASH. Whenever the distribution
provided for in this Section 3 shall be paid in property other than cash, the
value of such distribution shall be the fair market value of such property as
determined in good faith by the Board of Directors of the Corporation.

        4.      VOTING POWER.

                Except as otherwise required by law, each holder of Series C
Preferred Stock shall be entitled to vote on all matters and shall be entitled
to that number of votes equal to the number of votes that would be accorded to
the largest number of whole shares of Common Stock into which such holder's
shares of Series C Preferred Stock could be converted, pursuant to the
provisions of Section 5 of this Certificate, at the record date for the
determination of shareholders entitled to vote on such matter or, if no such
record date is established, at the date such vote is taken or any written
consent of shareholders is solicited. The holders of shares of Series C
Preferred Stock and Common Stock shall be entitled to vote together as a single
class on all matters. The holders of Series C Preferred Stock shall not be
entitled to vote as a separate class or voting group on any plan of merger.

        5.      CONVERSION RIGHTS.

                The holders of the Series C Preferred Stock shall have the
following conversion rights:

                5.1 GENERAL. Subject to and in compliance with the provisions of
this Section 5, any shares of Series C Preferred Stock may, at the option of the
holder, be converted at any time or from time to time into fully paid and
nonassessable shares (calculated as to each conversion to the largest whole
share) of Common Stock. The number of shares of Common Stock to which a holder
of Series C Preferred Stock shall be entitled upon conversion shall be the
product obtained by multiplying the appropriate Applicable Conversion Rate
(determined as provided in Sections 5.3, 5.4 and 5.5) by the number of shares of
Series C Preferred Stock being converted.

                5.2 MANDATORY CONVERSION.

                    (a) CONVERSION UPON MERGER, CONSOLIDATION, SHARE EXCHANGE OR
SALE OF ASSETS.

                        All the outstanding shares of Series C Preferred Stock
shall, at the option of the Corporation and upon written notice to the holders
thereof given not less than 30
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days prior to the closing of a merger or consolidation of the Corporation with
or into another Corporation, share exchange or the sale of all or substantially
all of the Corporation's assets to any other person, be converted, effective
upon such closing, into the number of shares of Common Stock to which a holder
of Series C Preferred Stock shall be entitled upon conversion pursuant to
Section 5.1, unless redeemed by the holder as provided herein. For purposes of
the preceding sentence, a merger, consolidation or share exchange shall only be
deemed to occur if, after giving effect to such merger, consolidation or share
exchange, the holders of the Corporation's outstanding capital stock (determined
on a fully diluted basis) immediately prior to the merger, consolidation or
share exchange, will cease to own immediately following the merger,
consolidation or share exchange the Corporation's (or the surviving
corporation's) outstanding capital stock (on a fully diluted basis) representing
at lest 50% of the equity value of the Corporation (or the surviving
corporation) as reasonably determined by the Corporation's board of directors.
Such conversion shall occur automatically on the effective date of such event
without any further action by such holders and whether or not the certificates
representing such shares are surrendered to the Corporation or its transfer
agent for the Common Stock, except that any holder may elect to have such
holder's Series C shares redeemed at the liquidation value by sending a notice
of redemption to the Corporation at any time prior to the expiration of the 30
day notice. Nothing in this Section 5.2, however, shall limit or in any way
restrict the rights of the holders of shares of Series C Preferred Stock to
convert such shares into shares of Common Stock at any time pursuant to Section
5.1 immediately above. Notwithstanding any other provision of this subparagraph,
the occurrence of a merger or consolidation of the Corporation with or into
another corporation, share exchange or the sale of all or substantially all of
the Corporation's assets to any other person, shall not be considered a
liquidation, dissolution or winding up of the Corporation under Section 3 of
this Certificate.

                    (b) SURRENDER OF CERTIFICATES.

                    Upon the occurrence of a conversion specified in this
Section 5.2, the holders of such Series C Preferred Stock shall surrender the
certificates representing such shares at the office of the Corporation or of its
transfer agent for the Common Stock. Thereupon, the Corporation or its transfer
agent shall issue and deliver to such holder a certificate or certificates for
the number of shares of Common Stock into which the shares of the Series C
Preferred Stock surrendered were convertible on the date on which such
conversion occurred. The Corporation shall not be obligated to issue
certificates evidencing the shares of Common Stock issuable upon such conversion
unless certificates evidencing such shares of the Series C Preferred Stock being
converted are either delivered to the Corporation or any such transfer agent or
the holder notifies the Corporation or any such transfer agent that such
certificates have been lost, stolen or destroyed and executes an agreement
satisfactory to the Corporation to indemnify the Corporation from any loss
incurred by it in connection therewith.

                5.3 SERIES C APPLICABLE CONVERSION RATE. The conversion rate for
each share of the Series C Preferred Stock in effect at any time (the "Series C
Applicable Conversion Rate") shall be the quotient obtained by dividing $20 by
the Applicable Conversion Value, calculated as provided in Section 5.4.



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                5.4 APPLICABLE CONVERSION VALUE. The Applicable Conversion Value
shall be $12 for the Series C Preferred Stock, except that such amount shall be
adjusted from time to time in accordance with this Section 5.

                5.5 ADJUSTMENTS TO APPLICABLE CONVERSION VALUE. Upon the
happening of an Extraordinary Common Stock Event (as hereinafter defined), the
Applicable Conversion Value shall, simultaneously with the happening of such
Extraordinary Common Stock Event, be adjusted by multiplying the then effective
Applicable Conversion Value by a fraction, the numerator of which shall be the
number of shares of Common Stock outstanding immediately prior to such
Extraordinary Common Stock Event and the denominator of which shall be the
number of shares of Common Stock outstanding immediately after such
Extraordinary Common Stock Event, and the product so obtained shall thereafter
be the Applicable Conversion Value. The Applicable Conversion Value, as so
adjusted, shall be readjusted in the same manner upon the happening of any
successive Extraordinary Common Stock Event or Events.

                "Extraordinary Common Stock Event" shall mean (i) the issue of
additional shares of the Common Stock as a dividend or other distribution on
outstanding Common Stock, (ii) the subdivision of outstanding shares of Common
Stock into a greater number of shares of the Common Stock or (iii) the
combination of outstanding shares of Common Stock into a smaller number of
shares of Common Stock.

                5.6 DIVIDENDS. In the event the Corporation shall make, issue or
fix a record date for the determination of holders of Common Stock entitled to
receive a dividend or other distribution payable in securities of the
Corporation other than shares of Common Stock or in assets, then and in each
such event provision shall be made so that the holders of Series C Preferred
Stock shall receive upon conversion thereof in addition to the number of shares
of Common Stock receivable thereupon the number of securities or such other
assets of the Corporation that they would have received had their Series C
Preferred Stock been converted into Common Stock on the date of such event and
had they thereafter, during the period from the date of such event to and
including the Conversion Date (as that term is hereafter defined in Section 5.9,
retained such securities or such other assets during such period, giving
application to all adjustments called for during such period under this Section
5 with respect to the rights of the holders of Series C Preferred Stock.

                5.7 RECAPITALIZATION OR RECLASSIFICATION. If the Common Stock
issuable upon the conversion of the Series C Preferred Stock shall be changed
into the same or different number of shares of any class or classes of stock of
the Corporation, whether by recapitalization, reclassification or otherwise
(other than a reorganization, merger, consolidation or sale of assets), then and
in each such event the holder of each share of Series C Preferred Stock shall
have the right thereafter to convert such share into the kind and amount of
shares of stock and other securities and property receivable upon such
reorganization, reclassification or other change by holders of the number of
shares of Common Stock into which such share of Series C Preferred Stock might
have been converted immediately prior to such reorganization, reclassification
or change, all subject to further adjustment as provided herein.



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                5.8 CERTIFICATE AS TO ADJUSTMENTS. In each case of an adjustment
or readjustment of the Applicable Conversion Rate, the Corporation will furnish
each holder of Series C Preferred Stock with a certificate showing such
adjustment or readjustment, and stating in reasonable detail the facts upon
which such adjustment or readjustment is based.

                5.9 EXERCISE OF CONVERSION PRIVILEGE. To exercise a conversion
privilege, a holder of Series C Preferred Stock shall surrender the certificate
or certificates representing the shares being converted to the Corporation at
its principal office, and shall give written notice to the Corporation at the
office that such holder elects to convert such shares. The certificate or
certificates for shares of Series C Preferred Stock surrendered for conversion
shall be accompanied by proper assignment thereof to the Corporation or in
blank. The date when such written notice is received by the Corporation,
together with the certificate or certificates representing the shares of Series
C Preferred Stock being converted, is the "Conversion Date." As promptly as
practicable after the Conversion Date, the Corporation shall issue and deliver
to the holder of the shares of Series C Preferred Stock being converted (i) such
certificate or certificates as it may request for the number of whole shares of
Common Stock issuable upon the conversion of such shares of Series C Preferred
Stock in accordance with the provisions of this Section 5, (ii) cash in the
amount of all accrued and unpaid dividends on such shares of Series C Preferred
Stock, if any, computed up to and including the Conversion Date and (iii) cash,
as provided in Section 5.10 in respect of any fraction of a share of Common
Stock issuable upon such conversion. Such conversion shall be deemed to have
been effected immediately prior to the close of business on the Conversion Date,
and at such time the rights of the holder as holder of the converted shares of
Series C Preferred Stock shall cease and the person or person in whose name or
names any certificate or certificates for shares of Common Stock shall be
issuable upon such conversion shall be deemed to have become the holder or
holders of record of the shares of Common Stock represented thereby.

                5.10 CASH IN LIEU OF FRACTIONAL SHARES. No fractional shares of
Common Stock shall be issued upon the conversion of shares of Series C Preferred
Stock. Instead of any fractional shares of Common Stock which would otherwise be
issuable upon conversion of Series C Preferred Stock, the Corporation shall pay
to the holder of the shares of Series C Preferred Stock which were converted a
cash adjustment in respect of such fractional shares in an amount equal to the
same fraction of the market price per share of the Common Stock (as determined
in a reasonable manner prescribed by the Board of Directors) at the close of
business on the Conversion Date. The determination as to whether or not any
fractional shares are issuable shall be based upon the total number of shares of
Series C Preferred Stock being converted at any one time by any holder thereof,
not upon each share of Series C Preferred Stock being converted.

                5.11 PARTIAL CONVERSION. In the event some but not all of the
shares of Series C Preferred Stock represented by a certificate or certificates
surrendered by a holder are converted, the Corporation shall execute and deliver
to the holder a new certificate representing the number of shares of Series C
Preferred Stock that were not converted.

                5.12 RESERVATION OF COMMON STOCK. The Corporation shall at all
times reserve and keep available out of its authorized but unissued shares of
Common Stock, solely for



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the purpose of effecting the conversion of the shares of the Series C Preferred
Stock, such number of its shares of Common Stock as shall from time to time be
sufficient to effect the conversion of all outstanding shares of the Series C
Preferred Stock. If at any time the number of authorized but unissued shares of
Common Stock shall not be sufficient to effect the conversion of all then
outstanding shares of the Series C Preferred Stock, the Corporation shall take
such corporate action as may be necessary to increase its authorized but
unissued shares of Common Stock to such number of shares as shall be sufficient
for such purpose.

        6.      REDEMPTION RIGHTS

                6.1 MANDATORY REDEMPTION. Except as otherwise provided in this
Section 6, on the fifth anniversary of the first date on which shares of Series
C Preferred Stock are issued (the "Mandatory Redemption Date"), the Corporation
shall redeem, out of funds legally available therefor, all outstanding shares of
Series C Preferred Stock, by paying therefor $20 per share, plus an amount equal
to any declared and unpaid dividends, if any, to such date, in cash (the
"Redemption Value").

                6.2 NOTICE OF REDEMPTION. Notice of any redemption of shares of
Series C Preferred Stock pursuant to Section 6.1 shall be given by notice to the
registered holders of the Series C Preferred Stock not less than 30, nor more
than 60 days prior to the date fixed for redemption (a "Redemption Notice"), to
each holder of Series C Preferred Stock to be redeemed, at such holder's address
as it appears on the transfer books of the Corporation. In order to facilitate
the redemption of Series C Preferred Stock, the Board of Directors may fix a
record date for the determination of Series C Preferred Stock to be redeemed, or
may cause the transfer books of the Corporation for the Series C Preferred Stock
to be closed, not more than 60 days or less than 30 days prior to the date fixed
for such redemption. At any time prior to the expiration of the Redemption
Notice, any holder of the Series C shares may exercise the conversion rights
pursuant to the provisions of Section 5.9 above.

                6.3 CANCELLATION OF SERIES C PREFERRED STOCK. Notice of
Redemption having been given as aforesaid in respect of shares of Series C
Preferred Stock to be redeemed pursuant to Section 6.1, notwithstanding that any
certificates for such shares shall not have been surrendered for cancellation,
from and after the date of redemption designated in the notice of redemption (i)
the shares represented thereby shall no longer be deemed outstanding, (ii) the
rights to receive dividends thereon shall cease to accrue, and (iii) all rights
of the holders of Series C Preferred Stock to be redeemed shall cease and
terminate, excepting only the right to receive the $20 per share redemption
price therefor, plus all accumulated and unpaid dividends (whether or not earned
or declared) to the date of redemption.

        7.      PUT RIGHT

                7.1 THE PUT. The Corporation hereby irrevocably grants and
issues to each holder of Series C Preferred Stock the right to require the
Corporation to purchase at any time (hereinafter referred to as the "Put") any
or all of such Series C Preferred Stock at the Redemption Value.



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                7.2 EXERCISE OF PUT. The holders of Series C Preferred Stock may
exercise the Put any time after the Issue Date (the "Exercise Period"). Any
holder of Series C Preferred Stock may exercise the Put during the Exercise
Period by delivery of a written notice to the Corporation specifying the number
of Series C Preferred Stock as to which the Put is being exercised, together
with delivery of one or more certificates representing the number of Series C
shares as to which the Put is being exercised, duly endorsed in blank by the
holders of Series C Preferred Stock or having attached thereto a stock power
duly executed by the holder of Series C Preferred Stock in proper form for
transfer.

                7.3 PAYMENT AND DELIVERY OF SERIES C PREFERRED STOCK. The
Corporation shall, within 20 calendar days of the receipt of notice from a
holder of Series C Preferred Stock of its exercise of the Put, pay to such
holder of Series C Preferred Stock in cash or by check, the Redemption Value for
each share of Series C Preferred Stock as to which such holder of Series C
Preferred Stock has exercised the Put. Any residual Series C shares represented
by the certificates surrendered but not included within the Put will be issued
in the name of the holder by the Corporation.