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                                                                   Exhibit 10.20

                   MUTUAL SEPARATION AND CONSULTING AGREEMENT

         THIS AGREEMENT is entered into by JAMES N. FARLEY (hereinafter
alternatively referred to as "Employee" or "Consultant") and SPEEDFAM-IPEC,
INC., on behalf of itself, its subsidiaries, affiliates, predecessors,
successors, agents, and employees (hereinafter referred to as "Employer" or the
"Company"). The parties agree as follows:

         I. RESIGNATION AS EMPLOYEE.

         1. Resignation/Separation. Employee resigns as the co-Chairman
(employee) of the Company, effective June 1, 1999 ("Termination Date").

         2. Separation Compensation. In exchange for the covenants set forth
herein, within eight (8) days of receiving this Agreement, duly executed, from
Employee, the Employer agrees to pay Employee: (A) all compensation, including
the fiscal year 1999 Incentive Award, accrued to Employee through May 31, 1999,
in accordance with the Employment Agreement dated as of June 1, 1998 between
Employee and the Company ("Employment Agreement") a copy of which is attached
hereto as Exhibit A; and (B) all payments provided under Section 12.2 of the
Employment Agreement by reason of the termination of Employee's employment
within two years of a Change of Control. Employee and the Company agree that the
resignation of Employee hereunder constitutes a Constructive Termination within
two years of a Change of Control, as set forth in the Employment Agreement. The
amount of Employee's fiscal year 1998 Incentive Award shall be deemed the
Employee's highest target annual incentive award opportunity for purposes of
Section 12.2.1(ii) of the Employment Agreement.

         3. Benefits. Following the termination of Employee's employment with
the Company, to the extent the Employee or his spouse shall no longer qualify to
participate under the Company's health insurance plan, the Company shall pay for
private health care insurance policies, with coverage comparable to the health
insurance coverage provided from time to time to officers of the Company, for
the Employee and his spouse for their lifetimes. Employee also will be provided
any other benefits for which he may be eligible in accordance with the terms of
any applicable benefit plans.

         4. General Release & Covenant Not To Sue. (A) Employee hereby releases
the Employer, its subsidiaries, affiliates, agents and employees from any and
all claims, contracts, and other liabilities of whatever kind, whether now known
or unknown, arising out of or in any way connected with his employment and the
cessation of that employment. This release includes, without limitation, any and
all claims under the Employee Retirement Income Security Act of 1974, Title VII
of the Civil Rights Act of 1964 as amended by the Civil Rights Act of 1991, the
Americans With Disabilities Act of 1990, the Age Discrimination in Employment
Act as modified by the Older Workers Benefit Protection Act, the Family and
Medical Leave Act, the Arizona Human Rights Act, and any other federal, state or
local human rights, civil rights, pension or labor laws, rules and/or
regulations, public policy, contract or tort law (regardless of whether of
statutory or common law origin), and any other action against the Employer based
upon
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any conduct up to and including the date of this Agreement. Employee further
agrees that he has not, nor will he ever institute any claim, action or other
proceeding that is subject to the foregoing release and acknowledges that this
Agreement shall bar any such action.

         (B) Employer hereby releases the Employee from any and all claims,
contracts, and other liabilities of whatever kind, whether now known or unknown,
arising out of or in any way connected with the Employee's employment or
cessation of that employment. Employer further agrees that it has not, nor will
it ever, institute any claim, action, or other proceeding that is subject to the
foregoing release and acknowledges that this Agreement shall bar any such
action.

         5. Restrictive Covenants. Employee agrees to abide by the Restrictive
Covenants set forth in Section 13 of the Employment Agreement for such periods
following the Termination Date as are provided therein.

         6. Board of Directors. This Agreement does not extend to, and Employee
is retaining, his position as a member and co-Chairman of the Board of Directors
of the Company. At any time that Employee wishes to stand for re-election to the
Board of Directors, the Company shall, to the greatest extent practicable,
nominate and support Employee for re-election thereto.

         II. RETENTION AS CONSULTANT

         1. Retention as Consultant. The Company hereby retains the Consultant
to perform Consulting Services, and the Consultant hereby accepts said
retention, all upon the terms and conditions hereinafter set forth. The
Consultant is and shall be deemed to be an independent contractor for all
purposes of this Agreement and is not and shall not be deemed to be an employee
of the Company for any purpose or in any respect whatsoever.

         2. Term. The term of the Consulting Agreement shall commence June 1,
1999 and end on May 31, 2002. The term of this Consulting Agreement shall
automatically continue for two additional one-year terms beginning June 1, 2002
unless either the Company or the Consultant shall notify the other at least
ninety (90) days prior to the expiration of the initial term or any renewal term
of its or his intention to terminate the Consulting Agreement as of the end of
its then current term.

         3. Consulting Fees. During the term of this Agreement and provided that
the Consultant is not in default under the terms of this Agreement, the Company
shall pay to the Consultant an annual fee of ONE HUNDRED THOUSAND DOLLARS
($100,000) as compensation for all services rendered by the Consultant under
this Agreement (the "Consulting Fees"); provided, however, in consideration of
the benefits otherwise payable to Consultant under this Agreement, Consultant
agrees to waive Consulting Fees for the first two fiscal years beginning June 1,
1999. The Company shall pay the Consultant the Consulting Fees in semiannual
installments. Except for the payment of

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the Consulting Fees and except for such benefits Consultant may be entitled to
for his services as a director of the Company and such other benefits Consultant
may be entitled to under Part I of this Agreement, the Consultant shall not be
entitled to, and shall not assert a claim for, any compensation or benefits from
the Company, including, without limitation, any benefits which may be provided
to the employees of the Company. Any payments made to the Consultant by the
Company hereunder shall be deemed for tax purposes to be in the nature of
compensation for services rendered.

         4. Consulting Duties. The Consultant will provide to the Chief
Executive Officer of the Company such consultation and advice, and such other
services in connection with the business of the Company, as the Chief Executive
Officer of the Company may reasonably request during the term of this Agreement
(collectively the "Consulting Services"). Consultant shall not be required to
provide Consulting Services for more than three days in any week or forty weeks
in any fiscal year.

         5. Expenses. The Company will reimburse Employee for all reasonable
business expenses which are incurred by Consultant in the course of providing
Consulting Services, upon presentation by Consultant of an itemized account of
such expense.

         III. COMPLETE AGREEMENT.

         1. Other than as set forth herein, Employee warrants that no promise or
inducement has been offered for this Agreement. The parties agree that this
Agreement sets forth the entire Agreement between them and supersedes any other
written or oral understandings (except to the extent the terms of the Employment
Agreement are referenced herein). No other promises or agreements shall be
binding unless reduced to writing and signed by the parties. The parties further
agree that if any provision of this Agreement is held invalid for any reason by
a court or other tribunal of competent jurisdiction, the remaining provisions
shall continue to be in full force and effect.

         2. No modification or amendment of, or waiver under, this Agreement
shall be valid unless in writing and signed by the Consultant and the Company.

         3. This Agreement shall be governed by and construed in accordance with
the laws of the State of Arizona.

         4. This Agreement may be executed in two or more counterparts, all of
which taken together shall constitute one and the same agreement.

         5. Employee has consulted with the law firm of Chapman and Cutler,
Chicago, Illinois, in the negotiation and preparation of this Agreement. Chapman
and Cutler has in the past and continues to provide legal counsel to Employee,
individually. Chapman and Cutler has in the past and continues to provide legal
counsel to the Company. Employee and the Company acknowledge and consent to the
dual representation of Employee and the Company in respect to the negotiation,
drafting and

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         execution of this Agreement. Employee and the Company each waive the
         conflict of interest presented by Chapman and Cutler's dual
         representation, and acknowledge the possibility of Chapman and Cutler
         having to withdraw from representation of both Employee and the Company
         in respect to this Agreement should a disagreement between the parties
         ensue following the execution of this Agreement.

         WHEREFORE, Employee affirms that he has read and understands this
Agreement, that he has consulted with an attorney concerning this Agreement, and
that he has entered into it with full knowledge of its significance. He further
affirms and understands that he has been given twenty-one (21) days to sign this
Agreement and that he will have an additional seven (7) days from the date he
signs this Agreement to revoke it if he so desires.

SPEEDFAM-IPEC, INC.                               EMPLOYEE



By /s/ Richard J. Faubert                         /s/ James N. Farley
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     ITS President & CEO                                 JAMES N. FARLEY


            6/17/99                                           6/17/99
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             Date                                              Date

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