EXHIBIT 3.6
                                 AMENDED BYLAWS

                                       OF

                                 SEMITOOL, INC.

                                 (May 20, 1998)


                                   ARTICLE I.

                                     Offices

         The principal  office of the  corporation in the State of Montana shall
be located in the City of Kalispell,  County of Flathead.  The  corporation  may
have such other  offices,  either  within or without the State of Montana as the
Board of  Directors  may  designate or as the  business of the  corporation  may
require from time to time.

         The  registered  office  of the  corporation  required  by the  Montana
Business  Corporation  Act to be  maintained in the State of Montana may be, but
need not be,  identical with the principal  office in the State of Montana,  and
the  registered  agent and the address of the  registered  office may be changed
from time to time by the Board of Directors.

                                   ARTICLE II.

                                  Shareholders

         Section 1. Annual Meeting. The annual meeting of the shareholders shall
be held in the month of  February,  beginning  with the year  1996,  and at such
date, and at such hour, and at such place as shall be determined by the Board of
Directors,  and such meeting shall be held for the purpose of electing directors
and for the  transaction  of such other business as may come before the meeting.
If the election of  directors  shall not be held on the date  designated  by the
action of the Board of Directors at the annual meeting of the  shareholders,  or
at any adjournment  thereof,  the Board of Directors shall cause the election to
be held at a special annual meeting of the  shareholders  as soon  thereafter as
conveniently  may be and as  determined  by the Board of Directors in accordance
with the statutes of the State of Montana.

         Section 2. Special  Meetings.  Special meetings of the shareholders for
any purpose or purposes,  unless otherwise  prescribed by statute, may be called
by the Chairman of the Board,  President,  Vice President,  Secretary, or by the
Board of Directors,  or by the holders of not less than one-fourth of all shares
entitled to vote at the meeting.


         Section 3. Place of Meeting.  The Board of Directors  may designate any
place either within or without the State of Montana, as the place of meeting for
any annual meeting or for any special  meeting called by the Board of Directors.
A Waiver of Notice signed by all shareholders  entitled to vote at a meeting may
designate any place, either within or without the State of Montana, as the place
for the holding of such  meeting.  If no  designation  is made,  or if a special
meeting be otherwise called, the place of meeting shall be the registered office
of the corporation in the State of Montana.

         Section 4. Notice of  Meeting.  Written or printed  notice  stating the
place, day and hour of the meeting and, in case of a special meeting the purpose
or purposes for which the meeting is called,  shall be  delivered  not less than
ten (10) nor more than sixty (60) days  before the date of the  meeting,  either
personally  or by mail,  by or at the  direction  of the  Chairman of the Board,
President,  or the Secretary,  or the officer or persons calling the meeting, to
each  shareholder of record  entitled to vote at such meeting.  If mailed,  such
notice shall be deemed to be delivered when deposited in the United States mail,
addressed  to the  shareholder  at his or her address as it appears on the stock
transfer books of the corporation, with postage thereon prepaid.


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         Section 5. Closing of Transfer  Books or Fixing of Record Date. For the
purpose  of  determining  shareholders  entitled  to notice of or to vote at any
meeting of shareholders or any adjournment  thereof or shareholders  entitled to
receive  payment  of any  dividend,  or in  order  to  make a  determination  of
shareholders  for any  other  proper  purpose,  the  Board of  Directors  of the
corporation  may  provide  that the stock  transfer  books shall be closed for a
stated  period,  but not to exceed,  in any case,  sixty (60) days. If the stock
transfer  books  shall be closed  for the  purpose of  determining  shareholders
entitled  to notice of or to vote at a meeting of the  shareholders,  such books
shall be closed  for a period of at least  ten (10) days  immediately  preceding
such meeting and not to exceed sixty (60) days preceding  such meeting.  In lieu
of closing the stock transfer books, the Board of Directors may fix in advance a
date as the record date for any such determination of shareholders, such date in
any case to be not more  than  sixty  (60) days  and,  in case of a  meeting  of
shareholders,  not  less  than  ten (10)  days  prior  to the date on which  the
particular  action requiring such  determination of shareholders is to be taken.
If the stock  transfer  books are not closed and no record date is fixed for the
determination  of shareholders  entitled to receive  payment of a dividend,  the
date on which the  resolution of the Board of Directors  declaring such dividend
is adopted,  as the case may be, shall be the record date for such determination
of shareholders.  When a determination  of shareholders  entitled to vote at any
meeting  of  shareholders  has  been  made as  provided  in this  section,  such
determination shall apply to any adjournment thereof.

         Section 6.  Voting  Right.  The officer or agent  having  charge of the
stock transfer books for shares of the corporation shall make, at least ten (10)
days  before  each  meeting  of  the  stockholders,   a  complete  list  of  the
shareholders  entitled  to vote at such  meeting,  or any  adjournment  thereof,
arranged  in  alphabetical  order,  with the address of and the number of shares
held by each,  which list,  for a period of ten (10) days prior to such meeting,
shall be kept on file at the registered  office of the  corporation and shall be
subject to  inspection  by any  shareholder  at any time during  usual  business
hours.  Such list shall also be produced  and kept open at the time and place of
the meeting and shall be subject to the inspection of any shareholder during the
whole time of the meeting. The original stock transfer book shall be prima facie
evidence  as to who  are the  shareholders  entitled  to  examine  such  list or
transfer books or to vote at any meeting of shareholders.

         Section  7.  Quorum.  A  majority  of  the  outstanding  shares  of the
corporation  entitled  to  vote,  represented  in  person  or  by  proxy,  shall
constitute  a quorum at a meeting of the  shareholders,  but in no event shall a
quorum  consist of less than one-third  (1/3) of the shares  entitled to vote at
the meeting. If a meeting cannot be organized because a quorum has not attended,
those  present  may  adjourn  the  meeting  from time to time  until a quorum is
present,  at which  time  any  business  may be  transacted  that may have  been
transacted at the meeting as originally  called.  The shareholders  present at a
duly  organized  meeting may continue to transact  business  until  adjournment,
notwithstanding  the  withdrawal  of enough  shareholders  to leave  less than a
quorum.

         Section 8. Voting of Shares. Subject to the provisions of Section 10 of
this Article II, each outstanding  share shall be entitled to one vote, and each
fractional  share shall be entitled to a corresponding  fractional vote, on each
matter submitted to a vote at a meeting of shareholders. Neither treasury shares
nor shares of its own stock held by the corporation in a fiduciary  capacity nor
shares held by another  corporation if a majority of the shares entitled to vote
for  the  election  of  director  of  such  other  corporation  is  held  by the
corporation  shall be voted at any meeting or counted in  determining  the total
number of outstanding shares at any given time.

         Shares held by an administrator,  executor, guardian or conservator may
be voted by him or her, either in person or by proxy, without a transfer of such
shares into his or her name.  Shares  standing in the name of the trustee may be
voted by him or her,  either  in person or by  proxy,  but no  trustee  shall be
entitled  to vote  shares  held by him or her  without a transfer of such shares
into his or her name.

         Shares  standing  in the  name  of a  receiver  may be  voted  by  such
receiver,  and shares held by or under the control of a receiver may be voted by
such receiver  without the transfer thereof into his or her name if authority so
to do be contained in an  appropriate  order of the court by which such receiver
was appointed.


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         A  shareholder  whose shares are pledged shall be entitled to vote such
shares until the shares have been transferred into the name of the pledgee,  and
thereafter the pledgee shall be entitled to vote the shares so transferred.

         Shares of its own stock belonging to the corporation or held by it in a
fiduciary capacity shall not be voted,  directly or indirectly,  at any meeting,
and shall not be counted in determining  the total number of outstanding  shares
at any given time.

         Section 9. Proxies. At all meetings of shareholders,  a shareholder may
vote by proxy  executed  in  writing  by the  shareholder  or by his or her duly
authorized attorney in fact. Such proxy shall be filed with the Secretary of the
corporation before or at the time of the meeting.  No proxy shall be valid after
eleven (11) months from the date of its execution,  unless otherwise provided in
the proxy.

         Section 10.  Cumulative  Voting.  At each election for directors  every
shareholder  entitled to vote at such election  shall have the right to vote, in
person or by proxy,  the number of shares and fractional  shares owned by him or
her for as many  persons  as there are  directors  to be  elected  and for whose
election  he or she has a right  to vote,  or to  cumulate  his or her  votes by
giving a candidate as many votes as the number of such  directors  multiplied by
the number of his or her shares including  fractional  shares shall equal, or by
distributing  such votes and fractional  votes on the same  principal  among any
number of candidates.

                                  ARTICLE III.

                               Board of Directors

         Section 1. General Powers.  The business and affairs of the corporation
shall be managed by its Board of Directors.

         Section 2. Number,  Tenure and Qualifications.  The number of directors
of the corporation shall be seven (7). Each director shall hold office until the
next annual meeting of  shareholders  and until his or her successor  shall have
been  elected and  qualified.  Directors  need not be  residents of the State of
Montana or shareholders of the corporation.

         Section 3. Annual Meeting. The annual meeting of the Board of Directors
shall be held without other notice than this Bylaw immediately after, and at the
same place as, the annual meeting of shareholders.

         Section  3a.  Regular  Meetings.  Regular  meetings  of  the  Board  of
Directors  shall be held at such time as shall be  determined by the Chairman of
the Board,  President, or by resolution of the Board. No notice need be given of
meetings  held  pursuant  to the  determination  by the  Chairman  of the Board,
President, or by resolution of the Board.

         Section 4. Special Meetings. Special meetings of the Board of Directors
may be called by or at the request of the Chairman of the Board,  President,  or
any two directors.  The person or persons authorized to call special meetings of
the Board of Directors may fix any place,  either within or without the State of
Montana,  as the place for holding any special meeting of the Board of Directors
called by them.

         Section 5.  Notice.  Notice of any  Special  Meeting  shall be given at
least two (2) days previously  thereto by written notice  delivered  personally,
mailed or faxed to each director at his or her business address, or by telegram.
If mailed,  such notice  shall be deemed to be delivered  when  deposited in the
United  States mail so addressed,  with postage  prepaid  thereon.  If notice is
given by fax, the notice shall be deemed to be delivered when the fax is sent to
the fax number  maintained in the records of the  corporation for each director.
If notice be given by telegram, such notice shall be deemed to be delivered when
the  telegram is  delivered  to the  telegraph  company.  Any director may waive
notice  of  any  meeting.  The  attendance  of a  director  at a  meeting  shall
constitute a waiver of notice of such meeting, except where a director attends a
meeting for the express  purpose of objecting to the transaction of any business
because  the  meeting  is not  lawfully  called or  convened.  The notice is not
required to describe the purpose of the meeting.


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         Section 6.  Quorum.  A majority  of the  number of  directors  fixed by
Section 2 of this Article III shall  constitute a quorum for the  transaction of
business  at any  meeting  of the  Board of  Directors,  but if less  than  such
majority  is present at the  meeting,  a majority of the  directors  present may
adjourn the meeting from time to time without further notice.

         Section 7. Vacancies.  Any vacancy  occurring in the Board of Directors
may be filled by the affirmative  vote of a majority of the remaining  directors
though less than a quorum of the Board of Directors.

         Section  8.  Compensation.  By  resolution  of the Board of  Directors,
directors may be paid their  expenses,  if any, of attendance at each meeting of
the  Board  of  Directors,  and  non-employee  directors  may be paid an  annual
retainer  plus a fixed  sum for  attendance  at each  meeting  of the  Board  of
Directors.  No such  payment  shall  preclude  any  director  from  serving  the
corporation in any other capacity and receiving compensation therefor.

                                   ARTICLE IV.

                                    Officers

         Section  1.  Number.  The  officers  of the  corporation  shall  be the
Chairman  of the Board,  a  President,  and such Vice  Presidents  (the  number,
qualification and titles thereof to be determined by the Board of Directors from
time to time,  and who may or may not be  directors),  as in the  opinion of the
Board the business of the corporation  requires,  a Secretary,  and a Treasurer.
Such other officers,  assistant officers,  and agents as may be necessary may be
elected or  appointed  from time to time by the Board of  Directors.  Any two or
more offices may be held by the same person, except for the offices of President
and Secretary.

         Section 2. Election and Term of Office. The officers of the corporation
to be elected by the Board of Directors  shall be elected  annually by the Board
of  Directors  at the first  meeting of the Board of  Directors  held after each
annual  meeting of the  shareholders.  If the election of officers  shall not be
held at such  meeting,  such  election  shall  be  held  as soon  thereafter  as
conveniently  may be. Each officer  shall hold office until his or her successor
shall have been duly elected and shall have  qualified or until his or her death
or until he or she  shall  resign  or shall  have  been  removed  in the  manner
hereinafter provided.

         Section 3.  Removal.  Any officer or agent  elected or appointed by the
Board of  Directors  may be removed by the Board of  Directors  whenever  in its
judgment the best interests of the corporation would be served thereby, but such
removal shall be without prejudice to the contract rights, if any, of the person
so removed.  Election or  appointment of an officer or agent shall not in itself
create contract rights.

         Section  4.  Vacancies.  A  vacancy  in any  office  because  of death,
resignation,  removal, disqualification or otherwise, may be filled by the Board
of Directors for the unexpired portion of the term.

         Section 5.  Chairman of the Board.  If the  Chairman of the Board is in
office,  he or she shall  preside at all  meetings of the  shareholders  and the
Board of  Directors.  During the absence or  disability  of the  Chairman of the
Board,  or during a vacancy in the  office of the  Chairman  of the  Board,  the
President  shall  preside at all meetings of the  stockholders  and the Board of
Directors, and shall perform such other duties as may be prescribed from time to
time by the Board of Directors or the Bylaws.

         Section 6. President.  The President  shall be the principal  executive
officer of the corporation and, subject to the control of the Board of Directors
shall, in general,  supervise and control all of the business and affairs of the
corporation.  He or she shall,  in the absence or  disability of the Chairman of
the  Board,  preside at all  meetings  of the  shareholders  and of the Board of
Directors. He or she may sign, with the Secretary or any other proper officer of
the corporation thereunto authorized by the Board of Directors, certificates for
shares of the corporation,  any deeds,  mortgages,  bonds,  contracts,  or other
instruments  which the Board of Directors has authorized to be executed,  except
in cases where the signing and execution thereof shall be expressly delegated by
the Board of Directors or by these Bylaws to some other  officer or agent of the
corporation,  or shall be required by law to be  otherwise  signed or  executed;
and, in general, shall perform all duties incident to the office of President


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and such other duties as may be prescribed  by the Board of Directors  from time
to time.

         Section 7. Vice  President.  In the absence of the  President or in the
event of his or her death,  inability or refusal to act, the Vice  President (or
in the event there be more than one Vice  President,  the Vice Presidents in the
order  designated  at the  time of  their  election,  or in the  absence  of any
designation,  then in the order of their  election)  shall perform the duties of
the President,  and when so acting,  shall have all the powers of and be subject
to all the restrictions upon the President.

         Section 8. Secretary.  The Secretary shall: (a) keep the minutes of the
shareholders and the Board of Directors'  meetings in one or more books provided
for that purpose; (b) see that all notices are duly given in accordance with the
provisions  of these  Bylaws or as  required  by law;  (c) be  custodian  of the
corporate  records and of the seal of the  corporation  and see that the seal of
the corporation is affixed to all documents, the execution of which on behalf of
the corporation  under its seal is duly  authorized;  (d) keep a register of the
post  office  address  of each  shareholder  which  shall  be  furnished  to the
Secretary by such shareholder; (e) sign with the President, or a Vice President,
certificates  for shares of the  corporation,  the  issuance of which shall have
been authorized by resolution of the Board of Directors; (f) have general charge
of the stock transfer books of the corporation;  and (g) in general, perform all
duties incident to the office of Secretary and such other duties as from time to
time  may  be  assigned  to him or her  by  the  President  or by the  Board  of
Directors.

         Section 9.  Treasurer.  The Treasurer shall have charge and supervision
and be  responsible  for all funds and securities of the  corporation  and shall
have charge and supervision of the deposits of all monies due and payable to the
corporation from any source whatsoever in such banks or depositories as shall be
selected  by the Board of  Directors,  and shall,  in  general,  perform all the
duties incident to the office of Treasurer and such other duties as from time to
time  may  be  assigned  to him or her  by  the  President  or by the  Board  of
Directors.

         Section  10.  Assistant  Secretaries  and  Assistant  Treasurers.   The
Assistant  Secretaries  shall  exercise  the duties of the  Secretary  and those
duties  incident to the office of the Secretary  when the Secretary is absent or
not  available and such other duties as shall be assigned by the President or by
the Board of  Directors.  The  Assistant  Treasurers  shall perform those duties
incident to the office of Treasurer  and those  assigned to the Treasurer in the
absence or unavailability of the Treasurer and such other duties as from time to
time  may  be  assigned  to him or her  by  the  President  or by the  Board  of
Directors.

         Section  11.  Exercise  of Rights  as  Stockholders.  Unless  otherwise
ordered by the Board of Directors,  the President or a Vice President  thereunto
duly authorized by the President,  shall have full power and authority on behalf
of the  corporation to attend and to vote at any meeting of  stockholders of any
corporation in which this corporation may hold stock, and may exercise on behalf
of this  corporation  any and  all of the  rights  and  powers  incident  to the
ownership of such stock at any such meeting,  and shall have power and authority
to execute and deliver  proxies and  consents on behalf of this  corporation  in
connection  with the  exercise  by this  corporation  of the  rights  and powers
incident to the ownership of such stock.  The Board of  Directors,  from time to
time, may confer like powers upon any other person or persons.

                                   ARTICLE V.

                   Certificates for Shares and Their Transfer

         Section 1. Certificates for Shares. Certificates representing shares of
the  corporation  shall be in such form as shall be  determined  by the Board of
Directors.  Such  certificates  shall  be  signed  by  the  President  or a Vice
President  and by  the  Secretary  or an  Assistant  Secretary.  The  names  and
addresses of the persons to whom the shares represented thereby are issued, with
the number of shares and dates of issue,  shall be entered on the stock transfer
books of the corporation.  All  certificates  surrendered to the corporation for
transfer  shall be canceled  and no new  certificate  shall be issued  until the
former  certificate for a like number of shares shall have been  surrendered and
canceled,  except that in case of a lost, destroyed or mutilated certificate,  a
new one may be issued  therefor upon such terms and indemnity to the corporation
as the Board of Directors may prescribe.


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         Section 2.  Transfer of Shares.  Transfer of shares of the  corporation
shall be made only on the stock transfer books of the  corporation by the holder
of record  thereof  or by his or her  legal  representative,  who shall  furnish
proper  evidence of authority to transfer,  or by his or her attorney  thereunto
authorized  by power of attorney  duly  executed and filed with the Secretary of
the  corporation,  and on surrender for cancellation of the certificate for such
shares.  The person in whose name shares  stand on the books of the  corporation
shall be deemed by the corporation to be the owner thereof for all purposes.

                                   ARTICLE VI.

                                   Fiscal Year

         The  fiscal  year  of the  corporation  shall  begin  on the 1st day of
October and end on the 30th day of September in each year.

                                  ARTICLE VII.

                                    Dividends

         The  Board  of  Directors  may  from  time  to  time  declare,  and the
corporation may pay dividends on its  outstanding  shares in the manner and upon
the terms and conditions provided by law.

                                  ARTICLE VIII.

                                      Seal

         The Board of Directors  shall  provide a corporate  seal which shall be
circular in form and shall have  inscribed  thereon the name of the  corporation
and the state of incorporation and the words "Corporate Seal".

                                   ARTICLE IX.

                                Waiver of Notice

         Whenever  any  notice is  required  to be given to any  shareholder  or
director of the  corporation  under the  provisions of these Bylaws or under the
provisions  of the  Montana  Business  Corporation  Act,  a waiver  therefor  in
writing, signed by the person or persons entitled to such notice, whether before
or after the time stated  therein,  shall be deemed  equivalent to the giving of
such notice.

                                   ARTICLE X.

                            Action Without a Meeting

         Any action  required  to be taken at a meeting of the  shareholders  or
directors  of the  corporation  or any action which may be taken at a meeting of
the shareholders or directors,  may be taken without a meeting if a consent,  in
writing,  setting  forth  the  action  so  taken,  shall  be  signed  by all the
shareholders  or directors  entitled to vote with respect to the subject  matter
thereof.  Such consent shall have the same effect as a unanimous vote and may be
stated in any articles or documents  filed with the Secretary of State under the
Montana Business Corporation Act.

                                   ARTICLE XI.

                                   Amendments

         These Amended Bylaws may be altered, amended or repealed and new Bylaws
may be adopted by the Board of  Directors  at any regular or special  meeting of
the Board of Directors.


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         We, the undersigned,  being all of the directors of SEMITOOL,  INC., do
hereby  formally and  regularly  adopt,  ratify and sign the  foregoing  Amended
Bylaws as the Bylaws of this corporation for the guidance of the corporation and
regulation of its business and as evidence of such adoption and ratification, we
do hereby set our hands this 20th day of May, 1998.


/s/R. Thompson                                    /s/C.S. Robinson
- ------------------------------                    ------------------------------
Raymon F. Thompson                                C.S. Robinson

/s/Daniel Eigeman                                 /s/Richard Dasen
- ------------------------------                    ------------------------------
Daniel Eigeman                                    Richard Dasen

/s/Howard Bateman                                 /s/John Osborne
- ------------------------------                    ------------------------------
Howard Bateman                                    John Osborne

/s/Timothy C. Dodkin
- ------------------------------
Timothy C. Dodkin


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