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                                                                   EXHIBIT 10.20

                       SETTLEMENT AGREEMENT AND MUTUAL RELEASE


     This Settlement Agreement and Mutual Release ("Agreement") is made by and 
between GENUS, INC.  (the "Company"), and MARY BOBEL ("Employee").

     WHEREAS, Employee was employed by the Company;
     
     WHEREAS, Employee and the Company entered into a Letter Agreement dated 
February 19,  1997.
     
     WHEREAS,  the Company and Employee have entered into a Change of Control 
Severance Agreement (the "Change of Control Agreement") .

     WHEREAS, the Company and Employee have mutually agreed to terminate the 
employment relationship and to release each other from any claims arising from 
or related to the employment relationship;

     NOW THEREFORE, in consideration of the mutual promises made herein, the 
Company and Employee (collectively referred to as "the Parties") hereby agree 
as follows:

     1.   RESIGNATION.  Employee resigns her employment with the Company and 
from her position as the Company's Chief Financial Officer effective July 15, 
1998. 

     2.   CONSIDERATION.  The Company agrees to pay Employee at her normal 
rate of pay of thirteen thousand seven hundred fifty Dollars ($13,750.00) per 
month, less applicable withholding, for nine (9) months from the effective 
date of her resignation (the "payment period") in accordance with the 
Company's payroll practices (provided that Employee does not revoke this 
Agreement under paragraph 8) up to and including the closing date of the sale 
of certain assets of the Ion Implantation systems business to Varian 
Associates, Inc. (the "Closing Date"). As of the Closing Date, however, all 
remaining pay due under this Agreement shall accelerate and become due and 
owing.  During the payment period, Employee will not be entitled to the 
accrual or continuation of any employee benefits, including, but not limited 
to, vacation benefits or bonuses.  The Company further agrees to pay up to 
$5000 in outplacement costs that Employee incurs by directly paying the 
outplacement vendor in an amount not to exceed $5,000 upon the receipt of such 
invoice(s) from the outplacement vendor.

     3.   VESTING OF STOCK.  The Parties agree that for purposes of 
determining the number of shares of the Company's common stock which Employee 
is entitled to purchase from the Company, Employee's vesting shall cease as of 
the date of this Agreement.  The exercise of any stock options shall continue 
to be subject to the terms and conditions of the Company's Stock Option Plan 
and the applicable Stock Option Agreement between Employee and the Company.

     4.   BENEFITS.  Employee shall have the right to convert his health
insurance benefits to 


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individual coverage pursuant to COBRA. 

     5.   CONFIDENTIAL INFORMATION.  Employee shall continue to maintain the 
confidentiality of all confidential and proprietary information of the Company 
and shall continue to comply with the terms and conditions of any 
Confidentiality Agreement between Employee and the Company.  Employee shall 
return all the Company property and confidential and proprietary information 
in his possession to the Company on the Effective Date of this Agreement.

     6.   PAYMENT OF SALARY.  Employee acknowledges and represents that the 
Company has paid all salary, wages, bonuses, accrued vacation, commissions and 
any and all other benefits due to Employee.

     7.   RELEASE OF CLAIMS.  Employee agrees that the foregoing consideration 
represents settlement in full of all outstanding obligations owed to Employee 
by the Company.  Employee and the Company, on behalf of themselves, and their 
respective heirs, family members, executors, officers, directors, employees, 
investors, shareholders, administrators, affiliates, divisions, subsidiaries, 
predecessor and successor corporations, and assigns, hereby fully and forever 
release each other and their respective heirs, family members, executors, 
officers, directors, employees, investors, shareholders, administrators, 
affiliates, divisions, subsidiaries, predecessor and successor corporations, 
and assigns, from, and agree not to sue concerning, any claim, duty, 
obligation or cause of action relating to any matters of any kind, whether 
presently known or unknown, suspected or unsuspected, that any of them may 
possess arising from any omissions, acts or facts that have occurred up until 
and including the Effective Date of this Agreement including, without 
limitation,
     
          (a)  any and all claims relating to or arising from Employee's 
employment relationship with the Company and the termination of that 
relationship; 

          (b)  any and all claims relating to, or arising from, Employee's 
right to purchase, or actual purchase of shares of stock of the Company, 
including, without limitation, any claims for fraud, misrepresentation, breach 
of fiduciary duty, breach of duty under applicable state corporate law, and 
securities fraud under any state or federal law; 

          (c)  any and all claims for wrongful discharge of employment; 
termination in violation of public policy; discrimination; breach of contract, 
both express and implied; breach of a covenant of good faith and fair dealing, 
both express and implied; promissory estoppel; negligent or intentional 
infliction of emotional distress; negligent or intentional misrepresentation; 
negligent or intentional interference with contract or prospective economic 
advantage; unfair business practices; defamation; libel; slander; negligence; 
personal injury; assault; battery; invasion of privacy; false imprisonment; 
and conversion;

          (d)  any and all claims for violation of any federal, state or 
municipal statute, including, but not limited to, Title VII of the Civil 
Rights Act of 1964, the Civil Rights Act of 1991, the Age Discrimination in 
Employment Act of 1967, the Americans with Disabilities Act of 1990, the Fair 
Labor Standards Act, the Employee Retirement Income Security Act of 1974, The 
Worker Adjustment and Retraining Notification Act, Older Workers Benefit 
Protection Act; the California 


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Fair Employment and Housing Act, and Labor Code section 201, ET SEQ. and 
section 970, ET SEQ.;

          (e)  any and all claims for violation of the federal, or any state, 
constitution; 

          (f)  any and all claims arising out of any other laws and 
regulations relating to employment or employment discrimination;  and

          (g)  any and all claims for attorneys' fees and costs.

The Company and Employee agree that the release set forth in this section 
shall be and remain in effect in all respects as a complete general release as 
to the matters released.  This release does not extend to any obligations 
incurred under this Agreement.

     8.   ACKNOWLEDGMENT OF WAIVER OF CLAIMS UNDER ADEA.  Employee 
acknowledges that he is waiving and releasing any rights he may have under the 
Age Discrimination in Employment Act of 1967 ("ADEA") and that this waiver and 
release is knowing and voluntary.  Employee and the Company agree that this 
waiver and release does not apply to any rights or claims that may arise under 
ADEA after the Effective Date of this Agreement.  Employee acknowledges that 
the consideration given for this waiver and release Agreement is in addition 
to anything of value to which Employee was already entitled.  Employee further 
acknowledges that he has been advised by this writing that (a) he should 
consult with an attorney PRIOR to executing this Agreement; (b) he has at 
least twenty-one (21) days within which to consider this Agreement; (c) he has 
at least seven (7) days following the execution of this Agreement by the 
parties to revoke the Agreement; and (d) this Agreement shall not be effective 
until the revocation period has expired.

     9.   CIVIL CODE SECTION 1542.  The Parties represent that they are not 
aware of any claim by either of them other than the claims that are released 
by this Agreement.  Employee and the Company acknowledge that they have been 
advised by legal counsel and are familiar with the provisions of California 
Civil Code Section 1542, which provides as follows:

          A GENERAL RELEASE DOES NOT EXTEND TO CLAIMS WHICH THE
          CREDITOR DOES NOT KNOW OR SUSPECT TO EXIST IN HIS FAVOR AT
          THE TIME OF EXECUTING THE RELEASE, WHICH IF KNOWN BY HIM
          MUST HAVE MATERIALLY AFFECTED HIS SETTLEMENT WITH THE
          DEBTOR.

     Employee and the Company, being aware of said code section, agree to 
expressly waive any rights they may have thereunder, as well as under any 
other statute or common law principles of similar effect.

     10.  NO PENDING OR FUTURE LAWSUITS.  Employee represents that he has no 
lawsuits, claims, or actions pending in his name, or on behalf of any other 
person or entity, against the Company or any other person or entity referred 
to herein.  Employee also represents that he does not 


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intend to bring any claims on his own behalf or on behalf of any other person 
or entity against the Company or any other person or entity referred to herein.

     11.  APPLICATION FOR EMPLOYMENT.  Employee understands and agrees that, 
as a condition of this Agreement, he shall not be entitled to any employment 
with the Company, its subsidiaries, or any successor, and he hereby waives any 
right, or alleged right, of employment or re-employment with the Company.  
Employee further agrees that he will not apply for employment with the 
Company, its subsidiaries or related companies, or any successor.

     12.  CONFIDENTIALITY.  The Parties hereto each agree to use their best 
efforts to maintain in confidence the existence of this Agreement, the 
contents and terms of this Agreement, and the consideration for this Agreement 
(hereinafter collectively referred to as "Settlement Information").  Each 
Party hereto agrees to take every reasonable precaution to prevent disclosure 
of any Settlement Information to third parties, and each agrees that there 
will be no publicity, directly or indirectly, concerning any Settlement 
Information.  The Parties hereto agree to take every precaution to disclose 
Settlement Information only to those employees, officers, directors, 
attorneys, accountants, governmental entities, and family members who have a 
reasonable need to know of such Settlement Information.

     13.  NO COOPERATION.  Employee agrees he will not act in any manner that 
might damage the business of the Company.  Employee agrees that he will not 
counsel or assist any attorneys or their clients in the presentation or 
prosecution of any disputes, differences, grievances, claims, charges, or 
complaints by any third party against the Company and/or any officer, 
director, employee, agent, representative, shareholder or attorney of the 
Company, unless under a subpoena or other court order to do so.

     14.  NON-DISPARAGEMENT.  Each party agrees to refrain from any 
defamation, libel or slander of the other, or tortious interference with the 
contracts and relationships of the other.  All inquiries by potential future 
employers of Employee will be directed to the Company 's Human Resources 
department.  Upon inquiry, the Company shall only state the following:  
Employee 's last position and dates of employment.  A press release announcing 
Employee's resignation shall be made.

     15.  TAX CONSEQUENCES.  The Company makes no representations or 
warranties with respect to the tax consequences of the payment of any sums to 
Employee under the terms of this Agreement.  Employee agrees and understands 
that he is responsible for payment, if any, of local, state and/or federal 
taxes on the sums paid hereunder by the Company and any penalties or 
assessments thereon. Employee further agrees to indemnify and hold the Company 
harmless from any claims, demands, deficiencies, penalties, assessments, 
executions, judgments, or recoveries by any government agency against the 
Company for any amounts claimed due on account of Employee's failure to pay 
federal or state taxes or damages sustained by the Company by reason of any 
such claims, including reasonable attorneys' fees.

     16.  COSTS.  The Parties shall each bear their own costs, expert fees,
attorneys' fees and 


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other fees incurred in connection with this Agreement.

     17.  ARBITRATION.  The Parties agree that any and all disputes arising 
out of the terms of this Agreement, their interpretation, and any of the 
matters herein released, shall be subject to binding arbitration in Santa 
Clara County before the American Arbitration Association under its California 
Employment Dispute Resolution Rules, or by a judge to be mutually agreed upon. 
 The Parties agree that the prevailing party in any arbitration shall be 
entitled to injunctive relief in any court of competent jurisdiction to 
enforce the arbitration award.  The Parties agree that the prevailing party in 
any arbitration shall be awarded its reasonable attorney's fees and costs.

     18.  AUTHORITY.  The Company represents and warrants that the undersigned 
has the authority to act on behalf of the Company and to bind the Company and 
all who may claim through it to the terms and conditions of this Agreement. 
Employee represents and warrants that he has the capacity to act on his own 
behalf and on behalf of all who might claim through him to bind them to the 
terms and conditions of this Agreement.  Each Party warrants and represents 
that there are no liens or claims of lien or assignments in law or equity or 
otherwise of or against any of the claims or causes of action released herein.

     19.  NO REPRESENTATIONS.  Each party represents that it has had the 
opportunity to consult with an attorney, and has carefully read and 
understands the scope and effect of the provisions of this Agreement.  Neither 
party has relied upon any representations or statements made by the other 
party hereto which are not specifically set forth in this Agreement.

     20.  SEVERABILITY.  In the event that any provision hereof becomes or is 
declared by a court of competent jurisdiction to be illegal, unenforceable or 
void, this Agreement shall continue in full force and effect without said 
provision.

     21.  ENTIRE AGREEMENT.  This Agreement represents the entire agreement 
and understanding between the Company and Employee concerning Employee's 
separation from the Company, and supersedes and replaces any and all prior 
agreements and understandings concerning Employee's relationship with the 
Company and his compensation by the Company.

     22.  NO ORAL MODIFICATION.  This Agreement may only be amended in writing 
signed by Employee and the President of the Company.

     23.  GOVERNING LAW.  This Agreement shall be governed by the laws of the 
State of California.

     24.  EFFECTIVE DATE.  This Agreement is effective seven days after it has 
been signed by both Parties.

     25.  COUNTERPARTS.  This Agreement may be executed in counterparts, and 
each counterpart shall have the same force and effect as an original and shall 
constitute an effective, binding agreement on the part of each of the 
undersigned.


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     26.  VOLUNTARY EXECUTION OF AGREEMENT.  This Agreement is executed 
voluntarily and without any duress or undue influence on the part or behalf of 
the Parties hereto, with the full intent of releasing all claims.  The Parties 
acknowledge that:

          (a)  They have read this Agreement;

          (b)  They have been represented in the preparation, negotiation, and 
execution of this Agreement by legal counsel of their own choice or that they 
have voluntarily declined to seek such counsel;

          (c)  They understand the terms and consequences of this Agreement 
and of the releases it contains; 

          (d)  They are fully aware of the legal and binding effect of this 
Agreement.

     IN WITNESS WHEREOF, the Parties have executed this Agreement on the 
respective dates set forth below.

                                   GENUS, Inc.



Dated:  May 4, 1998                By   /s/ WILLIAM W.R. ELDER             
                                        -----------------------------------
                                        William W. R. Elder
                                        Chairman of the Board


                                   Mary Bobel,  an individual


Dated:  May 4, 1998                /s/ MARY BOBEL        
                                   -----------------------------------
                                   Mary Bobel


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