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                                                                   EXHIBIT 10.38



June 27, 2000



Mr. Thomas J. Phillips
1314 Palo Duro Trail
Southlake, TX 76092

Dear Tom:

     This letter sets forth the substance of the separation agreement (the
"Agreement") which RF Monolithics, Inc. (the "Company") is offering to you to
aid in your employment transition, and is conditioned upon your execution of the
Employee Agreement and Release referenced in paragraph 13 of this Agreement, and
attached hereto as Exhibit B:

     1.   Separation.  Your last day of employment with the Company is July 5,
2000 (the "Separation Date"). The Company has accepted your resignation from the
position of Vice President, Manufacturing.

     2.   Severance Payments.  The Company will provide you with severance
payments equal to your present monthly salary of $10,416.67 per month, through
October 5, 2000, which will be paid in accordance with the Company's standard
payroll practices (the "Severance Payments"). In the event you have not obtained
employment as of October 5, 2000, the Company will continue to provide you with
Severance Payments until you obtain employment but, in any event, not longer
than December 31, 2000. You will be responsible for notifying the Company of the
date you accept new employment.

     3.   Health and Dental Care Coverage. You will have an opportunity to elect
to continue coverage under the Company's group health plan in accordance with,
and subject to, the provisions of the Consolidated Omnibus Budget Reconciliation
Act of 1985, as amended ("COBRA"). Should you elect to continue coverage, the
Company will charge you the appropriate employee monthly benefit premium through
October 5, 2000 and will deduct your portion of the monthly benefit premiums
from your Severance Payments. In the event you have not obtained employment as
of October 5, 2000, the Company will continue to provide this coverage in the
above-described manner until you obtain employment but, in any event, not longer
than December 31, 2000. You will be responsible for notifying the Company of the
date you accept new employment. Thereafter, the Company will provide group
health and dental coverage at prevailing COBRA rates so long as COBRA applies.

     4.   Vacation Pay.  You will receive payment for all accrued vacation
through July 5, 2000.
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     5.   Outplacement Services.  To assist you in obtaining another position,
RFM will pay for outplacement services up to $5,000.00.

     6.   Stock Options.  The vesting of the stock options which have been
granted to you through July 5, 2000, will be accelerated to provide you with the
vesting which would otherwise have occurred through October 5, 2000 under the
current vesting schedule.

     7.   Litigation.  The Company will continue to provide legal support for
you in the matter of Richard E. Lappin vs. RF Monolithics, Inc., et al, through
the law firm of Jackson Walker, L.L.P. You may continue to use the services of
Gary Fowler, or you may retain the services of David Watkins.

     8.   Other Compensation or Benefits.  You acknowledge that, except as
expressly provided in this Agreement, you will not receive any additional
compensation, severance or benefits after the Separation Date. Specifically, you
acknowledge that, because you will no longer be an employee of the Company after
the Separation Date, you will not be eligible to participate in the Company's
401(k) Plan. Additionally, you acknowledge that, as of the Separation Date, your
participation in the Company's Employee Stock Purchase Plan terminates, and any
accumulated payroll deductions which have not been applied to the purchase of
stock will be refunded to you as soon as is reasonably practical.

     9.   Expense Reimbursements.  You acknowledge that you have submitted your
final documented expense reimbursement statement reflecting all business
expenses you incurred through the Separation Date, if any, for which you seek
reimbursement. The Company will reimburse you for these expenses pursuant to its
regular business practice.

     10.  Return of Company Property. By July 5, 2000, you agree to return to
the Company all documents (and all copies thereof) and other Company property
which you have had in your possession at any time, including, but not limited
to, Company files, notes, drawings, records, business plans and forecasts,
financial information, specifications, computer-entry cards, identification
badges and keys; and, any materials of any kind which contain or embody any
proprietary or confidential information of the Company (and all reproductions
thereof).

     11.  Proprietary Information Obligations. You acknowledge your continuing
obligations under your Proprietary Information and Invention Agreement, both
during and after your employment, not to use or disclose any confidential or
proprietary information of the company without prior written authorization from
a duly authorized representative of the Company. A copy of your Proprietary
Information and Inventions Agreement is attached hereto as Exhibit A.

     12.  Confidentiality. The provisions of this Agreement shall be held in
strictest confidence by you and the Company and shall not be publicized or
disclosed in any manner whatsoever; provided, however, that: (a) you may
disclose this Agreement to your immediate family; (b) the parties may disclose
this Agreement in confidence to their respective attorneys, accountants,
auditors, tax preparers, and financial advisors; (c) the Company may disclose
this Agreement as necessary to fulfill standard or legally required corporate
reporting or disclosure
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requirements; and (d) the parties may disclose this Agreement insofar as such
disclosure may be necessary to enforce its terms or as otherwise required by
law.

     13.  Nondisparagement. Both you and the Company agree not to disparage the
other party, and the other party's officers, directors, employees, shareholders
and agents, in any manner likely to be harmful to them or their business,
business reputation or personal reputation; provided that both you and the
Company shall respond accurately and fully to any questions, inquiry or request
for information when required by legal process.

     14.  Release.  In exchange for the payments and other consideration under
this Agreement to which you would not otherwise be entitled, you agree to
execute the Employee Agreement and Release attached hereto as Exhibit B, and
incorporated by reference as fully set forth herein.

     15.  Confidential Arbitration. To ensure rapid and economical resolution of
any and all disputes which may arise in connection with the Agreement, you and
the Company agree that any and all disputes, claims, causes of action, in law or
equity, arising from or relating to the Agreement or its enforcement,
performance, breach, or interpretation, with the sole exception of those
disputes which may arise from your Proprietary Information and Inventions
Agreement, shall be resolved by final and binding confidential arbitration held
in Dallas, Texas through the American Arbitration Association, under its then-
existing Rules and Procedures. Nothing in this paragraph is intended to prevent
either you or the Company from obtaining injunctive relief in court to prevent
irreparable harm pending the conclusion of any such arbitration.

     16.  Miscellaneous.  This Agreement, including Exhibits A and B,
constitutes the complete, final and exclusive embodiment of the entire agreement
between you and the Company with regard to this subject matter. It is entered
into without reliance on any promise or representation, written or oral, other
than those expressly contained herein, and it supersedes any other such
promises, warranties or representations. This Agreement may not be modified or
amended except in writing signed by both you and a duly authorized officer of
the Company. This Agreement shall bind the heirs, personal representatives,
successors and assigns of both you and the Company, and inure to the benefit of
both you and the Company, their heirs, successors and assigns. If any provision
of this Agreement is determined to be invalid or unenforceable, in whole or in
part, this determination will not affect any other provision of this Agreement
and the provision in question shall be modified by a board of arbitration or a
court of competent jurisdiction so as to be rendered enforceable. This Agreement
has been made, delivered, and is to be performed, in full or in part, in Dallas,
County, Texas, and will be governed by, construed and enforced in accordance
with the laws of the State of Texas. All payments provided for hereunder will be
subject to applicable federal and state withholding provisions.
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     If this Agreement is acceptable to you, please sign below and the attached
Employee Agreement and Release, which is part of this Agreement, and return the
originals of both to me.

                                      Sincerely,

                                      RF Monolithics, Inc.



                                      By: _____________________________________
                                          David M. Kirk
                                          President and Chief Executive Officer

Exhibit A - Proprietary Information and Inventions Agreement
Exhibit B - Employee Agreement and Release

                                      AGREED:

                                      By: /s/ Thomas J. Phillips
                                          -------------------------------------
                                          Thomas J. Phillips