Exhibit 10.6

GUARANTY AND SURETYSHIP

    GUARANTY AND SURETYSHIP dated August 15, 2006, made and executed by
SEMITOOL, INC., a Montana corporation.

    The undersigned, intending to be legally bound, agrees:

SECTION 1. INTERPRETATION

    1.1        Defined Terms. The following terms shall have the following
meanings:

                 Bank. Sovereign Bank.

                 Borrower. Rhetech, Inc., a Delaware corporation.

                 Borrower’s Liabilities. All present and future liabilities of
the Borrower to the Bank under the Loan Documents, together with all interest on
such liabilities (at the annual rates set forth in the instruments evidencing
such liabilities) and all reasonable attorneys’fees, costs and expenses of
collection incurred by the Bank in enforcing such liabilities.

                 Event of Default. As that term is defined in subsection 5.1 of
this Guaranty.

                 Guarantor. Semitool, Inc., a Montana corporation.

                 Guarantor’s Liabilities. Individually and collectively, all
present and future liabilities of the Guarantor to the Bank under this Guaranty,
together with all reasonable attorneys’fees, costs and expenses of collection
incurred by the Bank in enforcing such liabilities.

                 Guaranty. This Guaranty and Suretyship, and any future
amendments to this Guaranty and Suretyship.

                 Loan Agreement. The Loan Agreement dated this date among the
Borrower, the Bank and the Lehigh County Industrial Development Authority, and
any future amendments to that Loan Agreement.

                 Property. All real and personal property of the Guarantor
(whether tangible or intangible) in or on which the Bank has a security
interest, lien, or other interest, or now or in the future is in the possession
or custody of, or in transit to, the Bank for any purpose, including
safekeeping, collection or pledge, for the Guarantor’s account, or as to which
the Guarantor may have any right or power including, without limitation, any
debts which the Bank might owe to the Guarantor.

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    1.2        Other Capitalized Terms. All capitalized words and/or phrases not
defined herein which are defined in the Loan Agreement shall have the meanings
set forth in the Loan Agreement.

    1.3        Other Terms. All terms not defined herein or in the Loan
Agreement which are defined in the Pennsylvania Uniform Commercial Code shall
have the meanings set forth in the Pennsylvania Uniform Commercial Code.

    1.4        Captions. The section and subsection captions of this Guaranty
are included for reference only and are not to be used in the construction of
this Guaranty.

    1.5        Severability. Any provision contained in this Guaranty which is
prohibited or unenforceable in any jurisdiction shall, as to such jurisdiction,
be ineffective to the extent of such prohibition or unenforceability without
invalidating the remaining provisions hereof, and any such prohibition or
unenforceability in any jurisdiction shall not invalidate or render
unenforceable such provision in any other jurisdiction.

    1.6        Construction. This Guaranty and the rights and obligations of the
Bank and the Guarantor under this Guaranty shall be governed and construed in
accordance with the domestic, internal laws (but not the law of the conflict of
laws) of the Commonwealth of Pennsylvania.

    1.7        Number and Gender. As to all pronouns and other terms in the
Guaranty (whether or not the same shall be a capitalized word and/or phrase),
the singular shall include the plural and the vice versa and any gender shall
include the other two genders, as the context may require.

SECTION 2. GUARANTY OF PAYMENT

    2.1        Guaranty of Payment. The Guarantor irrevocably and
unconditionally guarantees to the Bank, and becomes surety to the Bank for, the
prompt payment when due, whether by acceleration or otherwise, of the Borrower’s
Liabilities.

    2.2        Continuing Guaranty. This Guaranty is and shall be construed to
be an absolute, unlimited, and continuing guaranty of payment, regardless of the
present or future composition of the Borrower, and all of the Borrower’s
Liabilities to which this Guaranty applies, or may apply under the terms hereof,
shall be conclusively presumed to have been created in reliance hereon.

    2.3        Invalidity, Irregularity, Unenforceability, Etc. No Defense. No
invalidity, irregularity or unenforceability of, lack of prior enforcement of,
delay in enforcement of, or failure to preserve or enforce, any of the
Borrower’s Liabilities or of any security for the payment of the Borrower’s
Liabilities (although the Bank’s rights have been lost) shall affect, impair or
be a defense to this Guaranty. This Guaranty is and shall remain a primary
obligation of the Guarantor.

    2.4        Waivers. The Guarantor waives:

                ----notice of acceptance of this Guaranty,

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                ----notice of the creation of any of Borrower's Liabilities,

                ----presentment,

                ----demand for payment,

                ----protest,

                ----notice of dishonor,

                ----notice of nonpayment of any of Borrower's Liabilities,

                ----notice of suit or any other action by the Bank against the
Borrower and/or the Guarantor, and

                ----any other notice to the Borrower and/or the Guarantor.

    2.5        Statute of Limitations. Any acknowledgment or new promise with
regard to the Borrower’s Liabilities, whether by payment of principal or
interest or otherwise, and whether by the Borrower or others (including the
Guarantor) shall:

    (a)       toll the running of the statute of limitations in favor of the
Guarantor against the Bank, if the statute of limitations shall have begun to
run, and

    (b)       prevent the operation of the statute of limitations, if the period
of such statute of limitations shall have expired.

    2.6        Amounts Recovered From Bank. If claim is ever made upon the Bank
for repayment or recovery of any amount or amounts received by the Bank in
payment, or on account, of any of the Borrower’s Liabilities and the Bank repays
all or part of such amount by reason of:

    (a)       any judgment, decree, or order of any court or administrative body
having jurisdiction over the Bank or any of its property, or

    (b)       any settlement or compromise of any such claim effected by the
Bank with any such claimant (including the Borrower),

then and in such event the Guarantor agrees that any such judgment, decree,
order, settlement, or compromise shall be binding upon the Guarantor whether or
not this Guaranty shall have been revoked or any note or other instrument
evidencing the Borrower’s Liabilities shall have been cancelled, and the
Guarantor shall be and continue to remain liable to the Bank hereunder for the
amount so repaid or recovered to the same extent as if such amount had never
originally been received by the Bank.

    2.7        Bankruptcy Rescission or Avoidance. If any settlement, discharge,
payment, grant of security or transfer of property relating to discharging any
duty or liability created under this Guaranty is rescinded or avoided by virtue
of any provision of any bankruptcy, insolvency, or other similar law affecting
creditor’s rights, the Bank will be entitled to recover the value or amount of
any such settlement, discharge, payment, grant of security or transfer of
property from the Guarantor as if such settlement, discharge, payment, grant of
security or transfer of property had not occurred.

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    2.8        Satisfaction of Guarantor’s Liabilities. Satisfaction of the
Guarantor’s Liabilities shall not relieve the Guarantor from liability therefor
if such satisfaction is voided by a trustee in bankruptcy or receiver as a
preference, or similar voidable transfer, or for any other reason whatever.
Notwithstanding any provision of any document, but subject to the preceding
sentence, this Guaranty shall survive final payment and performance of all
Borrower’s Liabilities by three hundred seventy-five (375) days, or such longer
period as is otherwise provided herein or in any other document, unless a
bankruptcy or other similar insolvency proceeding is commenced within such
period by or against Borrower. If such a proceeding is commenced, this Guaranty
shall remain in effect until the expiration of any and all periods of limitation
for commencement of any fraudulent conveyance, fraudulent transfer, preference
or other avoiding action with respect to Borrower or Borrower’s Liabilities
without such an action having been commenced or, if such an action has been
commenced, until the final, non-appealable resolution thereof in favor of the
Bank.

    2.9        Place, Mode of Payment. The Guarantor shall make all payments
under this Guaranty to the Bank at its principal office at 2191 West Union
Boulevard, Bethlehem, Pennsylvania 18018. Payments shall be in lawful money of
the United States of America in funds immediately available to the Bank.

SECTION 3. BORROWER’S LIABILITIES; BANK ACTIONS

                The Bank may take any or all of the following actions at any
time and from time to time without notice to the Guarantor, without incurring
any responsibility to the Guarantor and without impairing or releasing the
Guarantor’s obligations under this Guaranty.

    3.1        Payment Terms. The Bank may change the manner, place or terms of
payment, and/or change or extend the time of payment of, renew or alter, or
change the interest rate or rates applicable to, any of the Borrower’s
Liabilities, any security for the Borrower’s Liabilities, or any liability
incurred directly or indirectly in respect of the Borrower’s Liabilities.

    3.2        Security. The Bank may sell, exchange, release, surrender,
realize upon, or otherwise deal with in any manner and in any order, any
property by whomsoever at any time pledged or mortgaged to secure, or howsoever
securing, the Borrower’s Liabilities, the Guarantor’s Liabilities or any other
liabilities incurred directly or indirectly with regard to the Borrower’s
Liabilities and the Guarantor’s Liabilities, and/or any offset thereagainst.

    3.3        Exercise of Rights. The Bank may exercise or refrain from
exercising any rights against the Borrower, the Guarantor or others arising out
of the Borrower’s Liabilities, or otherwise act or refrain from acting.

    3.4        Settlements. The Bank may settle or compromise any of the
Borrower’s Liabilities or the Guarantor’s Liabilities, any security for the
Borrower’s Liabilities or the Guarantor’s Liabilities, or any liability incurred
directly or indirectly in respect of the Borrower’s Liabilities or the
Guarantor’s Liabilities, and may subordinate the payment of all or any part of
such settlement or compromise to the payment of any liability of the Borrower
(whether or not then due) to the creditors of the Borrower other than the Bank
and the Guarantor.

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    3.5        Application of Payments. The Bank may apply any sums paid to the
Bank by whomsoever paid or howsoever realized to any of the Borrower’s
Liabilities regardless of which of the Borrower’s Liabilities remain unpaid.

SECTION 4. SECURITY FOR LIABILITIES; PROPERTY

    4.1        Grant of Security Interests. To secure payment of the Borrower’s
Liabilities and the Guarantor’s Liabilities, the Guarantor grants to the Bank a
lien on and security interest in all of the Property.

    4.2        Duties. The Bank shall not be required to take any steps
necessary to preserve any rights in any Property against prior parties who may
be liable in connection therewith. The Guarantor shall take all such steps.

    4.3        Permissible Actions. The Bank at any time and from time to time
may take any of the following actions without notice to the Guarantor, without
incurring responsibility to the Guarantor and without impairing or releasing the
Guarantor’s Liabilities under this Guaranty:

    (a)       the Bank may take any action it may deem appropriate for the care
or preservation of the Property or of any rights of the Guarantor or the Bank in
the Property,

    (b)       the Bank may demand, sue for, collect or receive any money or
property at any time due, payable or receivable on account of, or in exchange
for, any Property,

    (c)       the Bank may compromise and settle with any person liable on such
Property, or

    (d)       the Bank may extend the time of payment or otherwise change the
terms as to any party liable on such Property.

    4.4        Bank’s Lien. The Guarantor grants to the Bank, as further
security for the payment of the Borrower’s Liabilities and/or the Guarantor’s
Liabilities, a lien upon and a right of setoff with respect to any deposit
account of the Guarantor with the Bank and any other debts that the Bank may owe
to the Guarantor from time to time. The Bank may, upon the occurrence of an
Event of Default, and at any time and from time to time thereafter, at its
option and without notice, appropriate and apply toward the payment of any of
the Borrower’s Liabilities and/or the Guarantor’s Liabilities the balance of
each such deposit account of the Guarantor with, and each such claim of the
Guarantor against, the Bank.

SECTION 5. EVENTS OF DEFAULT; REMEDIES

    5.1        Events of Default. The occurrence of any one or more of the
following shall be deemed an Event of Default hereunder:

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    (a)       The occurrence of an Event of Default as defined in Section 14.01
of the Loan Agreement.

    (b)       Failure by the Guarantor to pay any monies due under this Guaranty
upon demand by Bank.

    (c)       Failure by the Guarantor to observe or perform any other covenant,
condition, term, or provision contained in this Guaranty, if such failure
continues for a period of ten (10) days or more after written notice from Bank.

    (d)       The dissolution of the Guarantor.

    (e)       The insolvency (however evidenced) of the Borrower or the
Guarantor.

    (f)       Any adverse change in the financial condition of the Borrower or
the Guarantor.

    (g)       The suspension of businesses of the Borrower or the Guarantor.

    (h)       The issuance of any warrants, process or order of attachment,
garnishment or other lien and/or the filing of a lien as a result thereof
against the property of the Borrower or the Guarantor.

    (i)       The making by the Borrower or the Guarantor of an assignment for
the benefit of creditors, or a trustee or receiver being appointed for the
Borrower or the Guarantor or for any property of any of them.

    (j)       Any proceeding being commenced by or against the Borrower or the
Guarantor under any bankruptcy, reorganization, arrangement of debt, insolvency,
readjustment of debt, receivership, liquidation or dissolution law or statute.

    (k)       It appears that any representation to any financial or other
statement of the Borrower or the Guarantor, delivered to Bank by or on behalf of
the Borrower or the Guarantor is untrue or incomplete.

        THE FOLLOWING SECTION CONTAINS A WARRANT OF AUTHORITY FOR AN ATTORNEY TO
CONFESS JUDGMENT AGAINST THE GUARANTOR. IN GRANTING THIS WARRANT OF ATTORNEY TO
CONFESS JUDGMENT AGAINST THE GUARANTOR, THE GUARANTOR HEREBY KNOWINGLY,
INTENTIONALLY AND VOLUNTARILY, AND, ON THE ADVICE OF SEPARATE COUNSEL OF THE
GUARANTOR, UNCONDITIONALLY WAIVES ANY AND ALL RIGHTS THE GUARANTOR HAS OR MAY
HAVE TO PRIOR NOTICE AND AN OPPORTUNITY FOR HEARING UNDER THE RESPECTIVE
CONSTITUTIONS AND LAWS OF THE UNITED STATES AND THE COMMONWEALTH OF
PENNSYLVANIA.

    5.2        Remedies. Upon the occurrence of an Event of Default, and so long
as such Event of Default shall continue unwaived:

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    (a)       the Bank may, at its option and upon notice to the Borrower or the
Guarantor, make the Borrower’s Liabilities, whether or not then due, immediately
due and payable under this Guaranty as to the Guarantor and the Bank shall be
entitled to enforce the Borrower’s Liabilities against the Guarantor,

    (b)       the Bank, without notice to the Borrower or the Guarantor, may
transfer into its own name or that of its nominee any Property, may notify any
obligor on any of such property to make payment to the Bank of any amounts due
on such Property, and/or take control of any proceeds of any of such Property,

    (c)        the Bank, with ten (10) days prior written notice to the
Guarantor and without advertisement or demand upon the Borrower or the Guarantor
or right of redemption (except as shall be required by applicable statute and
cannot be waived), may sell, resell, transfer and deliver all or part of the
Property at any brokers’ board or exchange or at public or private sale, for
cash or on credit or for future delivery, and in connection therewith may grant
options and may impose reasonable conditions such as requiring any purchaser of
any stock so sold to represent that such stock is purchased for investment
purposes only, and upon each such sale the Bank, unless prohibited by provision
of any applicable statute which cannot be waived, may purchase all or any part
of the Property, free from and discharged of all trusts, claims, right of
redemption and equities of the Guarantor,

    (d)       the Bank may exercise any of its rights and remedies provided by
the laws of the Commonwealth of Pennsylvania or any other jurisdiction, and

    (e)       the Guarantor authorizes and empowers any attorney of any court of
record of Pennsylvania or elsewhere to appear for and confess judgment against
it for the amount then outstanding under this Guaranty, as of any term, with or
without declaration filed, with costs of suit, release of errors, without stay
of execution and with attorneys’ fees, and does hereby voluntarily agree that
any real and personal property subject to such judgment may be sold on a writ
and hereby waives and releases all relief from any and all appraisement, stay or
exemption laws of any state, now in force or hereafter to be enacted. The power
to enter judgment against the Guarantor shall not be exhausted by any exercise
of the power and shall continue from time to time and at all times until full
payment of all amounts due under this Guaranty. For the purpose of entering
judgment, this Guaranty or a copy hereof verified by affidavit shall be a
sufficient warrant.

    5.3        Bank’s Expenses. The Guarantor shall pay to the Bank all
reasonable costs and expenses, including filing fees and reasonable attorneys’
fees, incurred by the Bank in connection with the custody, care, preservation or
collection of any of the Property, or in any proceedings to collect any of the
Guarantor’s Liabilities.

    5.4        Application of Funds. After deducting all costs and expenses
described in subsection 5.3 of this Guaranty, the Bank shall apply the balance
of the proceeds of any sale or collection to the Borrower’s Liabilities and the
Guarantor shall continue to be liable for any deficiency, with interest at the
annual rates set forth in the instruments evidencing those unpaid liabilities.

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    5.5        No Marshalling, Etc., Required. If any Event of Default shall
have occurred, the Bank shall not be required to marshall any present or future
security for, or guarantee of, the Borrower’s Liabilities held by it or to
resort to any such security or guarantee in any particular order. The Guarantor
waives, to the fullest extent the Guarantor lawfully can (a) any right the
Guarantor might have to require the Bank to pursue any particular remedy before
proceeding against the Guarantor, and (b) any right to the benefit of, or to
direct application of the proceeds of, any collateral until the Borrower’s
Liabilities have been paid in full.

SECTION 6. MISCELLANEOUS

    6.1        Waivers.

    (a)        No delay by the Bank in exercising, or any partial or single
exercise of, any of its options, powers or rights, shall constitute a waiver of
such option, power or right.

    (b)       No waiver of any of the Bank’s rights under this Guaranty, and no
amendment of this Guaranty shall be deemed to be made by the Bank unless in
writing and duly signed on behalf of the Bank.

    (c)       Any written waiver shall apply only with respect to the specific
instance involved and shall in no way impair the rights of the Bank or the
obligations of the Guarantor under this Guaranty in any other respect at any
other time.

    6.2        Service of Process. If the Bank brings any action or suit in any
court of record of Pennsylvania or the United States to enforce any or all
Guarantor’s Liabilities under this Guaranty, service of process may be made upon
the Guarantor by mailing a copy of the summons to the Guarantor.

    6.3        Subordination, Subrogation.

    (a)       The Guarantor shall not collect or enforce, attempt to collect or
enforce or receive any payment or property from the Borrower in respect of any
present or future obligation of the Borrower to the Guarantor until the
Borrower’s Liabilities have been paid or otherwise discharged in full.

    (b)       Unless and until the Bank receives payment in full of the
Borrower’s Liabilities from whatever sources, the Guarantor shall not be
subrogated to the rights of the Bank under the Loan Documents as the result of
any payment by, or enforcement of the obligations of, the Guarantor under this
Guaranty.

    6.4        Notices. All notices, requests and demands to or upon the parties
shall be deemed to have been given or made when deposited in the mails, postage
prepaid, certified mail, return receipt requested, or by personal delivery via
overnight courier service, charges prepaid, addressed as follows or to such
other address as the respective parties may designate in writing:

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    The Bank:
                        
                        

                        
                        

    with a copy to:
                        
                        
                        

                        

    The Guarantor:
                        
                        

                        

    with a copy to:
                        
                        

                        
                         Sovereign Bank
2191 West Union Boulevard
Bethlehem, PA 18018

Attention: Cheryl L. Davis, Vice President
               Commercial Banking Group

Stevens & Lee
190 Brodhead Road, Suite 200
P. O. Box 20830
Lehigh Valley, PA 18002

Attention: Edward A. Fedok, Esquire

Semitool, Inc.
655 West Reserve Drive
Kalispell, MT 59901

Attention: Vincent C. McGinty, President

Semitool, Inc.
655 West Reserve Drive
Kalispell, MT 59901

Attention: Richard Hegger, Esquire
               General Counsel

    6.5        Legal Effect.

    (a)       This Guaranty shall be binding upon the Guarantor and its
successors and assigns; provided, however, the Guarantor shall not assign its
duties under this Guaranty without the prior written consent of Bank.

    (b)       This Guaranty shall be binding upon, and shall inure to the
benefit of, the Bank, its successors and assigns. The term “Bank” includes any
agent of the Bank acting for it.

    6.6        Representations and Warranties. The Guarantor hereby represents
and warrants that:

    (a)       The Guarantor has the requisite power and/or authority to execute,
deliver and perform under this Guaranty and this Guaranty, when executed and
delivered to the Bank, will constitute a valid obligation of the Guarantor
legally binding upon it and enforceable in accordance with its terms.

    (b)       The execution and delivery of, and performance under, this
Guaranty will not violate or contravene any provision of any mortgage,
indenture, security agreement, contract, undertaking or other agreement to which
the Guarantor is a party or which purports to be binding upon it or any of its
assets nor result in the creation or imposition of any lien, charge, encumbrance
on, or security interest in, any of the Guarantor’s assets.

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    (c)       No actions, suits or proceedings before any court, governmental
department or agency are pending or, to the knowledge of the Guarantor,
threatened against the Guarantor or any of its assets that, if adversely
determined, could reasonably be expected to have a material adverse effect upon
the Guarantor’s financial condition, assets or ability to perform under this
Guaranty.

    6.7        Financial Statements. The Guarantor shall supply to the Bank any
and all financial statements as required by the Loan Agreement and shall supply
any other financial information reasonably requested by the Bank.

    6.8        Waiver of Immunity. The Guarantor hereby irrevocably and
unconditionally waives any right to claim immunity in respect of itself or any
of its property or assets, including immunity from jurisdiction, immunity from
attachment prior to entry of judgment, immunity from attachment in aid of
execution of judgment, and immunity from execution of judgment, all in respect
of any legal suit, action or proceeding arising out of, or relating to, this
Guaranty. The Guarantor further agrees that any such suit, action or proceeding
may be instituted in the courts of the Commonwealth of Pennsylvania or the
United States District Court for the Eastern District of Pennsylvania, and
irrevocably and unconditionally submits to the jurisdiction of any such court
for such purpose.

    6.9        Waiver of Trial by Jury. The Guarantor agrees that any suit,
action, or proceeding, whether claim or counterclaim, brought or instituted by
the Guarantor, by the Bank or by any successor or assign of any party on or with
respect to this Guaranty or any other Loan Document or which in any way relates,
directly or indirectly, to the Loan or any event, transaction or occurrence
arising out of or in any way connected with the Loan, or the dealings of the
parties with respect thereto, shall be tried only by a court and not by a jury.
THE GUARANTOR HEREBY EXPRESSLY WAIVES ANY RIGHT TO A TRIAL BY JURY IN ANY SUCH
SUIT, ACTION, OR PROCEEDING. THE GUARANTOR ACKNOWLEDGES AND AGREES THAT THIS
SECTION 6.9 IS A SPECIFIC AND MATERIAL ASPECT OF THIS AGREEMENT BETWEEN THE
PARTIES AND THAT THE BANK WOULD NOT EXTEND THE LOAN TO THE BORROWER IF THIS
WAIVER OF JURY TRIAL SECTION WERE NOT A PART OF THIS GUARANTY.

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        IN WITNESS WHEREOF, and intending to be legally bound hereby, the
Guarantor has executed this Guaranty under seal the day and year first above
written.

SEMITOOL, INC.

By: /s/ Raymon F. Thompson
——————————————
        Chairman and CEO

Attest: /s/ Richard C. Hegger
——————————————
         Secretary

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STATE OF MONTANA
                 
COUNTY OF :
:ss.
:

        On this ______ day of August, 2006, before me, a notary public, the
undersigned officer, personally appeared RAY THOMPSON, who acknowledged himself
to be the Chairman and CEO of SEMITOOL, INC., a Montana corporation, and that he
as such officer, being authorized to do so, executed the foregoing instrument
for the purposes therein contained by signing the name of the corporation by
himself as such officer.

        IN WITNESS WHEREOF, I have hereunto set my hand and official seal.

———————————————————
                     Notary Public

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