<PAGE>   1
                                                                    Exhibit 10.8


                                 LOAN AGREEMENT

<TABLE>
<CAPTION>
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      Principal        Loan Date      Maturity    Loan No.    Call 19   Collateral      Account     Officer    Initials
   $15,000,000.00      09-18-1998                  320-18                   070        0215644521    JAF35
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<S>                    <C>            <C>         <C>         <C>       <C>            <C>          <C>        <C>
References in the shaded area are for Lender's use only and do not limit the applicability of this document to any
particular loan or item.
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</TABLE>

Borrower:  AMERICAN XTAL TECHNOLOGY      Lender:  U.S. BANK NATIONAL ASSOCIATION
           4311 SOLAR WAY                         Fremont Business Banking
           FREMONT, CA  94538                     39510 Paseo Padre Pkwy
                                                  Fremont, CA  94538

     THIS LOAN AGREEMENT between AMERICAN XTAL TECHNOLOGY ("Borrower") and U.S.
BANK NATIONAL ASSOCIATION ("Lender") is made and executed on the following terms
and conditions. Borrower has received prior commercial loans from Lender or has
applied to Lender for a commercial loan or loans and other financial
accommodations, including those which may be described on any exhibit or
schedule attached to this Agreement. All such loans and financial
accommodations, together with all future loans and financial accommodations from
Lender to Borrower, are referred to in this Agreement individually as the "Loan"
and collectively as the "Loans." Borrower understands and agrees that: (a) in
granting, renewing, or extending any Loan, Lender is relying upon Borrower's
representations, warranties, and agreements, as set forth in this Agreement; (b)
the granting, renewing, or extending of any Loan by Lender at all times shall be
subject to Lender's sole judgment and discretion; and (c) all such Loans shall
be and shall remain subject to the following terms and conditions of this
Agreement.

     TERM. This Agreement shall be effective as of SEPTEMBER 18, 1998, and shall
continue thereafter until all Indebtedness of Borrower to Lender has been
performed in full and the parties terminate this Agreement in writing.

     DEFINITIONS. The following words shall have the following meanings when
used in this Agreement. Terms not otherwise defined in this Agreement shall have
the meanings attributed to such terms in the Uniform Commercial Code. All
references to dollar amounts shall mean amounts in lawful money of the United
States of America.

     Agreement. The word "Agreement" means this Loan Agreement, as this Loan
Agreement may be amended or modified from time to time, together with all
exhibits and schedules attached to this Loan Agreement from time to time.

     Account. The word "Account" means a trade account, account receivable, or
other right to payment for goods sold or services rendered owing to Borrower (or
to a third party grantor acceptable to Lender).

     Account Debtor. The words "Account Debtor" mean the person or entity
obligated upon an Account.


<PAGE>   2
     Advance. The word "Advance" means a disbursement of Loan funds under this
Agreement.

     Borrower. The word "Borrower" means AMERICAN XTAL TECHNOLOGY. The word
"Borrower" also includes, as applicable, all subsidiaries and affiliates of
Borrower as provided below in the paragraph titled "Subsidiaries and
Affiliates."

     Borrowing Base. The words "Borrowing Base" mean as determined by Lender
from time to time, the lesser of (a) $15,000,000.00; or (b) the sum of (i)
80.000% of the aggregate amount of Eligible Accounts, plus (ii) 50.000% of the
aggregate amount of eligible Inventory (not to exceed in corresponding Loan
amount based on Eligible Inventory of $5,500,000.00). The Borrowing Base formula
applies only when borrowings exceed $5,000,000.00

     Business Day. The words "Business Day" mean a day on which commercial banks
are open for business in the State of California.

     CERCLA. The word "CERCLA" means the Comprehensive Environmental Response,
Compensation, and Liability Act of 1980, as amended.

     Cash Flow. The words "Cash Flow" mean net income after taxes, and exclusive
of extraordinary gains and income, plus depreciation and amortization.

     Collateral. The word "Collateral" means and includes without limitation all
property and assets granted as collateral security for a Loan, whether real or
personal property, whether granted directly or indirectly, whether granted now
or in the future, and whether granted in the form of a security interest,
mortgage, deed of trust, assignment, pledge, chattel mortgage, chattel trust,
factor's lien, equipment trust, conditional sale, trust receipt, lien, charge,
lien or title retention contract, lease or consignment intended as a security
device, or any other security or lien interest whatsoever, whether created by
law, contract, or otherwise. The word "Collateral" includes without limitation
all collateral described below in the section titled "COLLATERAL."

     Debt. The word "Debt" means all of Borrower's liabilities excluding
Subordinated Debt.

     Eligible Accounts. The words "Eligible Accounts" mean, at any time, all of
Borrower's Accounts which contain selling terms and conditions acceptable to
Lender. The net amount of any Eligible Account against which Borrower may borrow
shall exclude all returns, discounts, credits, and offsets of any nature. Unless
otherwise agreed to by Lender in writing, Eligible Accounts do not include:

          (a)  Accounts with respect to which the Account Debtor is an officer,
an employee or agent of Borrower.


                                      -2-
<PAGE>   3
          (b)  Accounts with respect to which the Account Debtor is a subsidiary
of, or affiliated with or related to Borrower or its shareholders, officers, or
directors.

          (c)  Accounts with respect to which goods are placed on consignment,
guaranteed sale, or other terms by reason of which the payment by the Account
Debtor may be conditional.

          (d)  Accounts with respect to which Borrower is or may become liable
to the Account Debtor for goods sold or services rendered by the Account Debtor
to Borrower.

          (e)  Accounts which are subject to dispute, counterclaim, or setoff.

          (f)  Accounts with respect to which the goods have not been shipped or
delivered, or the services have not been rendered, to the Account Debtor.

          (g)  Accounts with respect to which Lender, in its sole discretion,
deems the creditworthiness or financial condition of the Account Debtor to be
unsatisfactory.

          (h)  Accounts of any Account Debtor who has filed or has had filed
against it a petition in bankruptcy or an application for relief under any
provision of any state or federal bankruptcy, insolvency, or debtor-in-relief
acts; or who has had appointed a trustee, custodian, or receiver for the assets
of such Account Debtor; or who has made an assignment for the benefit of
creditors or has become insolvent or fails generally to pay its debts (including
its payrolls) as such debts become due.

          (i)  Accounts with respect to which the Account Debtor is the United
States government or any department or agency of the United States.

          (j)  Accounts which have not been paid in full within 90 DAYS from the
invoice date. The entire balance of any Account of any single Account debtor
will be ineligible whenever the portion of the Account which has not been paid
within 90 DAYS from the invoice date is in excess of 25.000% of the total amount
outstanding on the Account.

          (k)  That portion of the Accounts of any single Account Debtor which
exceeds 20.000% of all of Borrower's Accounts.

          (l)  Accounts with respect to Datings, Progress Billings, Retainage,
Cash Sales, Cash on Delivery, Potential Offsets and Service Charges.

          (m)  Accounts with respect to which the Account Debtor is not a
resident of the United States, except to the extent such Accounts are supported
by insurance, bonds or other assurances satisfactory to Lender. (Foreign
advances will be allowed as pre-qualified by CRD).

     Eligible Inventory. The words "Eligible Inventory" mean, at any time, all
of Borrower's Inventory as defined below except:


                                      -3-
<PAGE>   4
          (a)  Inventory which is not owned by Borrower free and clear of all
security interests, liens, encumbrances, and claims of third parties.

          (b)  Inventory which Lender, in its sole discretion, deems to be
obsolete, unsalable, damaged, defective, or unfit for further processing.

          (c)  Eligible inventory for purposes of determining the Borrower's
Borrowing Base shall be defined as raw material at cost and scrap value of WIP
and finished goods.

     ERISA. The word "ERISA" means the Employee Retirement Income Security Act
of 1974, as amended.

     Event of Default. The words "Event of Default" mean and include without
limitation any of the Events of Default set forth below in the section titled
"EVENTS OF DEFAULT."

     Expiration Date. The words "Expiration Date" mean the date of termination
of Lender's commitment to lend under this Agreement.

     Grantor. The word "Grantor" means and includes without limitation each and
all of the persons or entities granting a Security Interest in any Collateral
for the Indebtedness, including without limitation all Borrowers granting such a
Security Interest.

     Guarantor. The word "Guarantor" means and includes without limitation each
and all of the guarantors, sureties, and accommodation parties in connection
with any indebtedness.

     Indebtedness. The word "Indebtedness" means and includes without limitation
all Loans, together with all other obligations, debts and liabilities of
Borrower to Lender, or any one or more of them, as well as all claims by Lender
against Borrower, or any one or more of them; whether now or hereafter existing,
voluntary or involuntary, due or not due, absolute or contingent, liquidated or
unliquidated; whether Borrower may be liable individually or jointly with
others; whether Borrower may be obligated as a guarantor, surety, or otherwise;
whether recovery upon such indebtedness may be or hereafter may become barred by
any statute of limitations; and whether such Indebtedness may be or hereafter
may become otherwise unenforceable.

     Inventory. The word "Inventory" means all of Borrower's raw materials, work
in process, finished goods, merchandise, parts and supplies, of every kind and
description, and goods held for sale or lease or furnished under contracts of
service in which Borrower now has or hereafter acquires any right, whether held
by Borrower or others, and all documents of title, warehouse receipts, bills of
lading, and all other documents of every type covering all or any part of the
foregoing. Inventory includes inventory temporarily out of Borrower's custody or
possession and all returns on Accounts.


                                      -4-
<PAGE>   5
     Lender. The word "Lender" means U.S. BANK NATIONAL ASSOCIATION, its
successors and assigns.

     Line of Credit. The words "Line of Credit" mean the credit facility
described in the Section titled "LINE OF CREDIT" below.

     Liquid Assets. The words "Liquid Assets" mean Borrower's cash on hand plus
Borrower's readily marketable securities.

     Loan. The word "Loan" or "Loans" means and includes without limitation any
and all commercial loans and financial accommodations from Lender to Borrower,
whether now or hereafter existing, and however evidenced, including without
limitation those loans and financial accommodations described herein or
described on any exhibit or schedule attached to this Agreement from time to
time.

     Note. The word "Note" means and includes without limitation Borrower's
promissory note or notes, if any, evidencing Borrower's Loan obligations in
favor of Lender, as well as any substitute, replacement or refinancing note or
notes therefor.

     Permitted Liens. The words "Permitted Liens" mean: (a) liens and security
interests securing indebtedness owed by Borrower to Lender; (b) liens for taxes,
assessments, or similar charges either not yet due or being contested in good
faith; (c) liens of materialmen, mechanics, warehousemen, or carriers, or other
like liens arising in the ordinary course of business and securing obligations
which are not yet delinquent; (d) purchase money liens or purchase money
security interests upon or in any property acquired or held by Borrower in the
ordinary course of business to secure indebtedness outstanding on the date of
this Agreement or permitted to be incurred under the paragraph of this Agreement
titled "Indebtedness and Liens"; (e) liens and security interests which, as of
the date of this Agreement, have been disclosed to and approved by the Lender in
writing; and (f) those liens and security interests which in the aggregate
constitute an immaterial and insignificant monetary amount with respect to the
net value of Borrower's assets.

     Related Documents. The words "Related Documents" mean and include without
limitation all promissory notes, credit agreements, loan agreements,
environmental agreements, guaranties, security agreements, mortgages, deeds of
trust, and all other instruments, agreements and documents, whether now or
hereafter existing, executed in connection with the Indebtedness.

     Security Agreement. The words "Security Agreement" mean and include without
limitation any agreements, promises, covenants, arrangements, understandings or
other agreements, whether created by law, contract, or otherwise, evidencing,
governing, representing, or creating a Security Interest.

     Security Interest. The words "Security Interest" mean and include without
limitation any type of collateral security, whether in the form of a lien,
charge, mortgage, deed of trust, assignment, pledge, chattel mortgage, chattel
trust, factor's lien, equipment trust, 


                                      -5-
<PAGE>   6
conditional sale, trust receipt, lien or title retention contract, lease or
consignment intended as a security device, or any other security or lien
interest whatsoever, whether created by law, contract, or otherwise.

     SARA. The word "SARA" means the Superfund Amendments and Reauthorization
Act of 1986 as now or hereafter amended.

     Subordinated Debt. The words "Subordinated Debt" mean indebtedness and
liabilities of Borrower which have been subordinated by written agreement to
indebtedness owed by Borrower to Lender in form and substance acceptable to
Lender.

     Tangible Net Worth. The words "Tangible Net Worth" mean Borrower's total
assets excluding all intangible assets (i.e., goodwill, trademarks, patents,
copyrights, organizational expenses, and similar intangible items, but including
leaseholds and leasehold improvements) less total Debt.

     Working Capital. The words "Working Capital" mean Borrower's current
assets, excluding prepaid expenses, less Borrower's current liabilities.

     LINE OF CREDIT. Lender agrees to make Advances to Borrower from time to
time from the date of this Agreement to the Expiration Date, provided the
aggregate amount of such Advances outstanding at any time does not exceed the
Borrowing Base. Within the foregoing limits, Borrower may borrow, partially or
wholly prepay, and reborrow under this Agreement as follows.

     Conditions Precedent to Each Advance. Lender's obligation to make any
Advance to or for the account of Borrower under this Agreement is subject to the
following conditions precedent, with all documents, instruments, opinions,
reports, and other items required under this Agreement to be in form and
substance satisfactory to Lender:

          (a)  Lender shall have received evidence that this Agreement and all
Related Documents have been duly authorized, executed, and delivered by Borrower
to Lender.

          (b)  Lender shall have received such opinions of counsel, supplemental
opinions, and documents as Lender may request.

          (c)  The security interests in the Collateral shall have been duly
authorized, created, and perfected with first lien priority and shall be in full
force and effect.

          (d)  All guaranties required by Lender for the Line of Credit shall
have been executed by each Guarantor, delivered to Lender, and be in full force
and effect.

          (e)  Lender, at its option and for its sole benefit, shall have
conducted an audit of Borrower's Accounts, Inventory, books, records, and
operations, and Lender shall be satisfied as to their condition.


                                      -6-
<PAGE>   7
          (f)  Borrower shall have paid to Lender all fees, costs, and expenses
specified in this Agreement and the Related Documents as are then due and
payable.

          (g)  There shall not exist at the time of any Advance a condition
which would constitute an Event of Default under this Agreement, and Borrower
shall have delivered to Lender the compliance certificate called for in the
paragraph below titled "Compliance Certificate."

     Making Loan Advances. Advances under the credit facility, as well as
directions for payment from Borrower's accounts, may be requested orally or in
writing by authorized persons. Lender may, but need not, require that all oral
requests be confirmed in writing. Each Advance shall be conclusively deemed to
have been made at the request of and for the benefit of Borrower (a) when
credited to any deposit account of Borrower maintained with Lender or (b) when
advanced in accordance with the instructions of an authorized person. Lender, at
its option, may set a cutoff time, after which all requests for Advances will be
treated as having been requested on the next succeeding Business Day.

     Mandatory Loan Repayments. If at any time the aggregate principal amount of
the outstanding Advances shall exceed the applicable Borrowing Base, Borrower,
immediately upon written or oral notice from Lender, shall pay to Lender an
amount equal to the difference between the outstanding principal balance of the
Advances and the Borrowing Base. On the Expiration Date, Borrower shall pay to
Lender in full the aggregate unpaid principal amount of all Advances then
outstanding and all accrued unpaid interest, together with all other applicable
fees, costs and charges, if any, not yet paid.

     Loan Account. Lender shall maintain on its books a record of account in
which Lender shall make entries for each Advance and such other debits and
credits as shall be appropriate in connection with the credit facility. Lender
shall provide Borrower with periodic statements of Borrower's account, which
statements shall be considered to be correct and conclusively binding on
Borrower unless Borrower notifies Lender to the contrary within thirty (30) days
after Borrower's receipt of any such statement which Borrower deems to be
incorrect.

     COLLATERAL. To secure payment of the Line of Credit and performance of all
other Loans, obligations and duties owed by Borrower to Lender, Borrower (and
others, if required) shall grant to Lender Security Interests in such property
and assets as Lender may require (the "Collateral"), including without
limitation Borrower's present and future Accounts, general intangibles, and
Inventory. Lender's Security Interests in the Collateral shall be continuing
liens and shall include the proceeds and products of the Collateral, including
without limitation the proceeds of any insurance. With respect to the
Collateral, Borrower agrees and represents and warrants to Lender:

     Perfection of Security Interests. Borrower agrees to execute such financing
statements and to take whatever other actions are requested by Lender to perfect
and continue Lender's Security Interests in the Collateral Upon request of
Lender, Borrower will deliver to Lender any and all of the documents evidencing
or constituting the Collateral, and Borrower will note Lender's interest upon
any and all chattel paper if not delivered to Lender for 


                                      -7-
<PAGE>   8
possession by Lender. Contemporaneous with the execution of this Agreement,
Borrower will execute one or more UCC financing statements and any similar
statements as may be required by applicable law, and will file such financing
statements and all such similar statements in the appropriate location or
locations. Borrower hereby appoints Lender as its irrevocable attorney-in-fact
for the purpose of executing any documents necessary to perfect or to continue
any Security Interest. Lender may at any time, and without further authorization
from Borrower, file a carbon, photograph, facsimile, or other reproduction of
any financing statement for use as a financing statement. Borrower will
reimburse Lender for all expenses for the perfection, termination, and the
continuation of the perfection of Lender's security interest in the Collateral.
Borrower promptly will notify Lender of any change in Borrower's name including
any change to the assumed business names of Borrower. Borrower also promptly
will notify Lender of any change in Borrower's Social Security Number or
Employer Identification Number. Borrower further agrees to notify Lender in
writing prior to any change in address or location of Borrower's principal
governance office or should Borrower merge or consolidate with any other entity.

     Collateral Records. Borrower does now, and at all times hereafter shall,
keep correct and accurate records of the Collateral, all of which records shall
be available to Lender or Lender's representative upon demand for inspection and
copying at any reasonable time. With respect to the Accounts, Borrower agrees to
keep and maintain such records as Lender may require, including without
limitation information concerning Eligible Accounts and Account balances and
agings. With respect to the Inventory, Borrower agrees to keep and maintain such
records as Lender may require, including without limitation information
concerning Eligible Inventory and records itemizing and describing the kind,
type, quality, and quantity of Inventory, Borrower's Inventory costs and selling
prices, and the daily withdrawals and additions to Inventory.

     Collateral Schedules. Concurrently with the execution and delivery of this
Agreement, Borrower shall execute and deliver to Lender schedules of Accounts
and Inventory and Eligible Accounts and Eligible Inventory, in form and
substance satisfactory to the Lender. Thereafter and at such frequency as Lender
shall require, Borrower shall execute and deliver to Lender such supplemental
schedules of Eligible Accounts and Eligible Inventory and such other matters and
information relating to the Accounts and Inventory as Lender may request.

     Representations and Warranties Concerning Accounts. With respect to the
Accounts, Borrower represents and warrants to Lender: (a) Each Account
represented by Borrower to be an Eligible Account for purposes of this Agreement
conforms to the requirements of the definition of an Eligible Account; (b) All
Account information listed on schedules delivered to Lender will be true and
correct, subject to immaterial variance; and (c) Lender, its assigns, or agents
shall have the right at any time and at Borrower's expense to inspect, examine,
and audit Borrower's records and to confirm with Account Debtors the accuracy of
such Accounts.

     Representations and Warranties Concerning Inventory. With respect to the
Inventory, Borrower represents and warrants to Lender: (a) All Inventory
represented by 


                                      -8-
<PAGE>   9
Borrower to be Eligible Inventory for purposes of this Agreement conforms to the
requirements of the definition of Eligible Inventory; (b) All Inventory values
listed on schedules delivered to Lender will be true and correct, subject to
immaterial variance; (c) The value of the Inventory will be determined on a
consistent accounting basis; (d) Except as agreed to the contrary by Lender in
writing, all Eligible Inventory is now and at all times hereafter will be in
Borrower's physical possession and shall not be held by others on consignment,
sale on approval, or sale or return; (e) Except as reflected in the Inventory
schedules delivered to Lender, all Eligible Inventory is now and at all times
hereafter will be of good and merchantable quality, free from defects; (f)
Eligible Inventory is not now and will not at any time hereafter be stored with
a bailee, warehouseman, or similar party without Lender's prior written consent,
and, in such event, Borrower will concurrently at the time of bailment cause any
such bailee, warehouseman, or similar party to issue and deliver to Lender, in
form acceptable to Lender, warehouse receipts in Lender's name evidencing the
storage of Inventory; and (g) Lender, its assigns, or agents shall have the
right at any time and at Borrower's expense to inspect and examine the Inventory
and to check and test the same as to quality, quantity, value, and condition.

     REPRESENTATIONS AND WARRANTIES. Borrower represents and warrants to Lender,
as of the date of this Agreement, as of the date of each disbursement of Loan
proceeds, as of the date of any renewal, extension or modification of any Loan,
and at all times any Indebtedness exists:

     Organization. Borrower is a corporation which is duly organized, validly
existing, and in good standing under the laws of the State of California and is
validly existing and in good standing in all states in which Borrower is doing
business. Borrower has the full power and authority to own its properties and to
transact the businesses in which it is presently engaged or presently proposes
to engage. Borrower also is duly qualified as a foreign corporation and is in
good standing in all states in which the failure to so qualify would have a
material adverse effect on its businesses or financial condition.

     Authorization. The execution, delivery, and performance of this Agreement
and all Related Documents by Borrower, to the extent to be executed, delivered
or performed by Borrower, have been duly authorized by all necessary action by
Borrower; do not require the consent or approval of any other person, regulatory
authority or governmental body; and do not conflict with, result in a violation
of, or constitute a default under (a) any provision of its articles of
incorporation or organization, or bylaws, or any agreement or other instrument
binding upon Borrower or (b) any law, governmental regulation, court decree, or
order applicable to Borrower.

     Financial Information. Each financial statement of Borrower supplied to
Lender truly and completely disclosed Borrower's financial condition as of the
date of the statement, and there has been no material adverse change in
Borrower's financial condition subsequent to the date of the most recent
financial statement supplied to Lender. Borrower has no material contingent
obligations except as disclosed in such financial statements.


                                      -9-
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     Legal Effect. This Agreement constitutes, and any instrument or agreement
required hereunder to be given by Borrower when delivered will constitute,
legal, valid and binding obligations of Borrower enforceable against Borrower in
accordance with their respective terms.

     Properties. Except for Permitted Liens, Borrower owns and has good title to
all of Borrower's properties free and clear of all Security Interests, and has
not executed any security documents or financing statements relating to such
properties. All of Borrower's properties are titled in Borrower's legal name,
and Borrower has not used, or filed a financing statement under, any other name
for at least the last (5) years.

     Hazardous Substances. The terms "hazardous waste," "hazardous substance,"
"disposal," "release," and "threatened release," as used in this Agreement,
shall have the same meanings as set forth in the "CERCLA," "SARA," the Hazardous
Materials Transportation Act, 49 U.S.C. Section 1801, et seq., the Resource
Conservation and Recovery Act, 42 U.S.C. Section 6901, et seq., Chapters 6.5
through 7.7 of Division 20 of the California Health and Safety Code, Section
25100, et seq., or other applicable state or Federal laws, rules, or regulations
adopted pursuant to any of the foregoing. Except as disclosed to and
acknowledged by Lender in writing, Borrower represents and warrants that: (a)
During the period of Borrower's ownership of the properties, there has been no
use, generation, manufacture, storage, treatment, disposal, release or
threatened release of any hazardous waste or substance by any person on, under,
about or from any of the properties. (b) Borrower has no knowledge of, or reason
to believe that there has been (i) any use, generation, manufacture, storage,
treatment, disposal, release, or threatened release of any hazardous waste or
substance on, under, about or from the properties by any prior owners or
occupants of any of the properties, or (ii) any actual or threatened litigation
or claims of any kind by any person relating to such matters. (c) Neither
Borrower nor any tenant, contractor, agent or other authorized user of any of
the properties shall use, generate, manufacture, store, treat, dispose of, or
release any hazardous waste or substance on, under, about or from any of the
properties; and any such activity shall be conducted in compliance with all
applicable federal, state, and local laws, regulations, and ordinances,
including without limitation those laws, regulations and ordinances described
above. Borrower authorizes Lender and its agents to enter upon the properties to
make such inspections and tests as Lender may deem appropriate to determine
compliance of the properties with this section of the Agreement. Any inspections
or tests made by Lender shall be at Borrower's expense and for Lender's purposes
only and shall not be construed to create any responsibility or liability on the
part of Lender to Borrower or to any other person. The representations and
warranties contained herein are based on Borrower's due diligence in
investigating the properties for hazardous waste and hazardous substances.
Borrower hereby (a) releases and waives any future claims against Lender for
indemnity or contribution in the event Borrower becomes liable for cleanup or
other costs under any such laws, and (b) agrees to indemnify and hold harmless
Lender against any and all claims, losses, liabilities, damages, penalties, and
expenses which Lender may directly or indirectly sustain or suffer resulting
from a breach of this section of the Agreement or as a consequence of any use,
generation, manufacture, storage, disposal, release or threatened release of a
hazardous waste or substance on the properties. The provisions of this section
of the Agreement, including the obligation to 


                                      -10-
<PAGE>   11
indemnify, shall survive the payment of the Indebtedness and the termination or
expiration of this Agreement and shall not be affected by Lender's acquisition
of any interest in any of the properties, whether by foreclosure or otherwise.

     Litigation and Claims. No litigation, claim, investigation, administrative
proceeding or similar action (including those for unpaid taxes) against Borrower
is pending or threatened, and no other event has occurred which may materially
adversely affect Borrower's financial condition or properties, other than
litigation, claims, or other events, if any, that have been disclosed to and
acknowledged by Lender in writing.

     Taxes. To the best of Borrower's knowledge, all tax returns and reports of
Borrower that are or were required to be filed, have been filed, and all taxes,
assessments and other governmental charges have been paid in full, except those
presently being or to be contested by Borrower in good faith in the ordinary
course of business and for which adequate reserves have been provided.

     Lien Priority. Unless otherwise previously disclosed to Lender in writing,
Borrower has not entered into or granted any Security Agreements, or permitted
the filing or attachment of any Security Interests on or affecting any of the
Collateral directly or indirectly securing repayment of Borrower's Loan and
Note, that would be prior or that may in any way be superior to Lender's
Security Interests and rights in and to such Collateral.

     Binding Effect. This Agreement, the Note, all Security Agreements directly
or indirectly securing repayment of Borrower's Loan and Note and all of the
Related Documents are binding upon Borrower as well as upon Borrower's
successors, representatives and assigns, and are legally enforceable in
accordance with their respective terms.

     Commercial Purposes. Borrower intends to use the Loan proceeds solely for
business or commercial related purposes.

     Employee Benefit Plans. Each employee benefit plan as to which Borrower may
have any liability complies in all material respects with all applicable
requirements of law and regulations, and (i) no Reportable Event nor Prohibited
Transaction (as defined in ERISA) has occurred with respect to any such plan,
(ii) Borrower has not withdrawn from any such plan or initiated steps to do so,
(iii) no steps have been taken to terminate any such plan, and (iv) there are no
unfunded liabilities other than those previously disclosed to Lender in writing.

     Location of Borrower's Offices and Records. Borrower's place of business,
or Borrower's chief executive office, if Borrower has more than one place of
business, is located at 4311 SOLAR WAY, FREMONT, CA 94538. Unless Borrower has
designated otherwise in writing this location is also the office or offices
where Borrower keeps its records concerning the Collateral.

     Information. All information heretofore or contemporaneously herewith
furnished by Borrower to Lender for the purposes of or in connection with this
Agreement or any transaction contemplated hereby is, and all information
hereafter furnished by or on behalf 


                                      -11-
<PAGE>   12
of Borrower to Lender will be, true and accurate in every material respect on
the date as of which such information is dated or certified; and none of such
information is or will be incomplete by omitting to state any material fact
necessary to make such information not misleading.

     Survival of Representations and Warranties. Borrower understands and agrees
that Lender, without independent investigation, is relying upon the above
representations and warranties in extending Loan Advances to Borrower. Borrower
further agrees that the foregoing representations and warranties shall be
continuing in nature and shall remain in full force and effect until such time
as Borrower's Indebtedness shall be paid in full, or until this Agreement shall
be terminated in the manner provided above, whichever is the last to occur.

     AFFIRMATIVE COVENANTS. Borrower covenants and agrees with Lender that,
while this Agreement is in effect, Borrower will:

     Litigation. Promptly inform Lender in writing of (a) all material adverse
changes in Borrower's financial condition, and (b) all existing and all
threatened litigation, claims, investigations, administrative proceedings or
similar actions affecting Borrower or any Guarantor which could materially
affect the financial condition of Borrower or the financial condition of any
Guarantor.

     Financial Records. Maintain its books and records in accordance with
generally accepted accounting principles, applied on a consistent basis, and
permit Lender to examine and audit Borrower's books and records at all
reasonable times.

     Financial Statements. Furnish Lender with, as soon as available, but in no
event later than ninety (90) days after the end of each fiscal year, Borrower's
balance sheet and income statement for the year ended, audited by a certified
public accountant satisfactory to Lender, and, as soon as available, but in no
event later than forty-five (45) days after the end of each fiscal quarter,
Borrower's balance sheet and profit and loss statement for the period ended,
prepared and certified as correct to the best knowledge and belief by Borrower's
chief financial officer or other officer or person acceptable to Lender. All
financial reports required to be provided under this Agreement shall be prepared
in accordance with generally accepted accounting principles, applied on a
consistent basis, and certified by Borrower as being true and correct.

     Additional Information. Furnish such additional information and statements,
lists of assets and liabilities, agings of receivables and payables, inventory
schedules, budgets, forecasts, tax returns, and other reports with respect to
Borrower's financial condition and business operations as Lender may request
from time to time.

     Financial Covenants and Ratios. Comply with the following covenants and
ratios:

     Net Worth Ratio. Maintain a ratio of Total Liabilities to Tangible Net
Worth of less than 1.00 TO 1.00.


                                      -12-
<PAGE>   13
     Working Capital. Maintain Working Capital in excess of $30,000,00.00.

     Current Ratio. Maintain a ratio of Current Assets to Current Liabilities in
excess of 1.50 TO 1.00.

     Cash Flow Requirements. Maintain Cash Flow at not less than the following
level: 1.50 TO 1.00 DEFINED AS: NET PROFIT AFTER TAXES PLUS DEPRECIATION PLUS
AMORTIZATION PLUS INTEREST EXPENSE MINUS DIVIDENDS MINUS WITHDRAWS MINUS
INTERNALLY FUNDED FIXED ASSETS DIVIDED BY CURRENT PORTION LONG TERM DEBT PLUS
INTEREST EXPENSE. (ONE TIME ALLOWANCE OF $1,760,000.00 TO BE ADDED BACK TO CASH
FLOW FOR FISCAL YEAR 1998 TO COMPENSATE FOR NON-FINANCEABLE PORTION OF
TECHNOLOGY DRIVE PROPERTY PURCHASE EFFECTIVE JUNE 30, 1998). Except as provided
above, all computations made to determine compliance with the requirements
contained in this paragraph shall be made in accordance with generally accepted
accounting principles, applied on a consistent basis, and certified by Borrower
as being true and correct.

     Insurance. Maintain fire and other risk insurance, public liability
insurance, and such other insurance as Lender may require with respect to
Borrower's properties and operations, in form, amounts, coverages and with
insurance companies reasonably acceptable to Lender. Borrower, upon request of
Lender, will deliver to Lender from time to time the policies or certificates of
insurance in form satisfactory to Lender, including stipulations that coverages
will not be canceled or diminished without at least ten (10) days' prior written
notice to Lender. Each insurance policy also shall include an endorsement
providing that coverage in favor of Lender will not be impaired in any way by
any act, omission or default of Borrower or any other person. In connection with
all policies covering assets in which Lender holds or is offered a security
interest for the Loans, Borrower will provide Lender with such loss payable or
other endorsements as Lender may require.

     Insurance Reports. Furnish to Lender, upon request of Lender, reports on
each existing insurance policy showing such information as Lender may reasonably
request, including without limitation the following: (a) the name of the
insurer; (b) the risks insured; (c) the amount of the policy; (d) the properties
insured; (e) the then current property values on the basis of which insurance
has been obtained, and the manner of determining those values; and (f) the
expiration date of the policy. In addition, upon request of Lender (however not
more often than annually), Borrower will have an independent appraiser
satisfactory to Lender determine, as applicable, the actual cash value or
replacement cost of any Collateral. The cost of such appraisal shall be paid by
Borrower.

     Other Agreements. Comply with all terms and conditions of all other
agreements, whether now or hereafter existing, between Borrower and any other
party and notify Lender immediately in writing of any default in connection with
any other such agreements.

     Loan Fees and Charges. In addition to all other agreed upon fees and
charges, pay the following: BORROWER AGREES TO PAY LENDER A NONREFUNDABLE LOAN
FEE (FOR LETTER OF CREDIT) IN THE AMOUNT OF $59,933.00.


                                      -13-
<PAGE>   14
     Loan Proceeds. Use all Loan proceeds solely for Borrower's business
operations, unless specifically consented to the contrary by Lender in writing.

     Taxes, Charges and Liens. Pay and discharge when due all of its
indebtedness and obligations, including without limitation all assessments,
taxes, governmental charges, levies and liens, of every kind and nature, imposed
upon Borrower or its properties, income, or profits, prior to the date on which
penalties would attach, and all lawful claims that, if unpaid, might become a
lien or charge upon any of Borrower's properties, income, or profits. Provided
however, Borrower will not be required to pay and discharge any such assessment,
tax, charge, levy, lien or claim so long as (a) the legality of the same shall
be contested in good faith by appropriate proceedings, and (b) Borrower shall
have established on its books adequate reserves with respect to such contested
assessment, tax, charge, levy, lien, or claim in accordance with generally
accepted accounting practices. Borrower, upon demand of Lender, will furnish to
Lender evidence of payment of the assessments, taxes, charges, levies, liens and
claims and will authorize the appropriate governmental official to deliver to
Lender at any time a written statement of any assessments, taxes, charges,
levies, liens and claims against Borrower's properties, income, or profits.

     Performance. Perform and comply with all terms, conditions, and provisions
set forth in this Agreement and in the Related Documents in a timely manner, and
promptly notify Lender if Borrower learns of the occurrence of any event which
constitutes an Event of Default under this Agreement or under any of the Related
Documents.

     Operations. Maintain executive and management personnel with substantially
the same qualifications and experience as the present executive and management
personnel; provide written notice to Lender of any change in executive and
management personnel; conduct its business affairs in a reasonable and prudent
manner and in compliance with all applicable federal, state and municipal laws,
ordinances, rules and regulations respecting its properties, charters,
businesses and operations, including without limitation, compliance with the
Americans With Disabilities Act and with all minimum funding standards and other
requirements of ERISA and other laws applicable to Borrower's employee benefit
plans.

     Inspection. Permit employees or agents of Lender at any reasonable time to
inspect any and all Collateral for the Loan or Loans and Borrower's other
properties and to examine or audit Borrower's books, accounts, and records and
to make copies and memoranda of Borrower's books, accounts, and records. If
Borrower now or at any time hereafter maintains any records (including without
limitation computer generated records and computer software programs for the
generation of such records) in the possession of a third party, Borrower, upon
request of Lender, shall notify such party to permit Lender free access to such
records at all reasonable times and to provide Lender with copies of any records
it may request, all at Borrower's expense.

     Compliance Certificate. Unless waived in writing by Lender, provide Lender
QUARTERLY (WITHIN 45 DAYS) and at the time of each disbursement of Loan proceeds
with a certificate executed by Borrower's chief financial officer, or other
officer or person acceptable 


                                      -14-
<PAGE>   15
to Lender, certifying that the representations and warranties set forth in this
Agreement are true and correct as of the date of the certificate and further
certifying that, as of the date of the certificate, no Event of Default exists
under this Agreement.

     Environmental Compliance and Reports. Borrower shall comply in all respects
with all environmental protection federal, state and local laws, statutes,
regulations and ordinances; not cause or permit to exist, as a result of an
intentional or unintentional action or omission on its part or on the part of
any third party, on property owned and/or occupied by Borrower, any
environmental activity where damage may result to the environment, unless such
environmental activity is pursuant to and in compliance with the conditions of a
permit issued by the appropriate federal, state or local governmental
authorities; shall furnish to Lender promptly and in any event within thirty
(30) days after receipt thereof a copy of any notice, summons, lien, citation,
directive, letter or other communication from any governmental agency or
instrumentality concerning any intentional or unintentional action or omission
on Borrower's part in connection with any environmental activity whether or not
there is damage to the environmental and/or other natural resources.

     Additional Assurances. Make, execute and deliver to Lender such promissory
notes, mortgages, deeds of trust, security agreements, financing statements,
instruments, documents and other agreements as Lender or its attorneys may
reasonably request to evidence and secure the Loans and to perfect all Security
Interests.

     RECOVERY OF ADDITIONAL COSTS. If the imposition of or any change in any
law, rule, regulation or guideline, or the interpretation or application of any
thereof by any court or administrative or governmental authority (including any
request or policy not having the force of law) shall impose, modify or make
applicable any taxes (except U.S. federal, state or local income or franchise
taxes imposed on Lender), reserve requirements, capital adequacy requirements or
other obligations which would (a) increase the cost to Lender for extending or
maintaining the credit facilities to which this Agreement relates, (b) reduce
the amounts payable to Lender under this Agreement or the Related Documents, or
(c) reduce the rate of return on Lender's capital as a consequence of Lender's
obligations with respect to the credit facilities to which this Agreement
relates, then Borrower agrees to pay Lender such additional amounts as will
compensate Lender therefore, within five (5) days after Lender's written demand
for such payment, which demand shall be accompanied by an explanation of such
imposition or charge and a calculation in reasonable detail of the additional
amounts payable by Borrower, which explanation and calculations shall be
conclusive in the absence of manifest error.

     NEGATIVE COVENANTS. Borrower covenants and agrees with Lender that while
this Agreement is in effect, Borrower shall not, without the prior written
consent of Lender:

     Indebtedness and Liens. (a) Except for trade debt incurred in the normal
course of business and indebtedness to Lender contemplated by this Agreement,
create, incur or assume indebtedness for borrowed money, including capital
lease, (b) except as allowed as a Permitted Lien, sell, transfer, mortgage,
assign, pledge, lease, grant a security interest in, or 



                                      -15-
<PAGE>   16
encumber any of Borrower's assets, or (c) sell with recourse any of Borrower's
accounts, except to Lender.

     Continuity of Operations. (a) Engage in any business activities
substantially different than those in which Borrower is presently engaged, (b)
cease operations, liquidate, merge, transfer, acquire or consolidate with any
other entity, change ownership, change its name, dissolve or transfer or sell
Collateral out of the ordinary course of business, (c) pay any dividends on
Borrower's stock (other than dividends payable in its stock), provided, however
that notwithstanding the foregoing, but only so long as no Event of Default has
occurred and is continuing or would result from the payment of dividends, if
Borrower is a "Subchapter S Corporation" (as defined in the Internal Revenue
Code of 1986, as amended), Borrower may pay cash dividends on its stock to its
shareholders from time to time in amounts necessary to enable the shareholders
to pay income taxes and make estimated income tax payments to satisfy their
liabilities under federal and state law which arise solely from their status as
Shareholders of a Subchapter S Corporation because of their ownership of shares
of stock of Borrower, or (d) purchase or retire any of Borrower's outstanding
shares or alter or amend Borrower's capital structure.

     Loans, Acquisitions and Guaranties. (a) Loan, invest in or advance money or
assets, (b) purchase, create or acquire any interest in any other enterprise or
entity, or (c) incur any obligation as surety or guarantor other than in the
ordinary course of business.

     CESSATION OF ADVANCES. If Lender has made any commitment to make any Loan
to Borrower, whether under this Agreement or under any other agreement, Lender
shall have no obligation to make Loan Advances or to disburse Loan proceeds if:
(a) Borrower or any Guarantor is in default under the terms of this Agreement or
any of the Related Documents or any other agreement that Borrower or any
Guarantor has with Lender; (b) Borrower or any Guarantor becomes insolvent,
files a petition in bankruptcy or similar proceedings, or is adjudged a
bankrupt; (c) there occurs a material adverse change in Borrower's financial,
condition, in the financial condition of any Guarantor, or in the value of any
Collateral securing any Loan; or (d) any Guarantor seeks, claims or otherwise
attempts to limit, modify or revoke such Guarantor's guaranty of the Loan or any
other loan with Lender.

     ADDITIONAL DEFINITIONS.

     Current Assets. The words "Current Assets" mean Borrower's cash on hand
plus Borrower's receivables plus inventory.

     Current Liabilities. The words "Current Liabilities" mean all Borrower's
notes payable plus Borrower's accounts payable plus Borrower's income taxes
payable plus Borrower's accruals plus Borrower's current portion of long term
debt.

     Current Ratio. The words "Current Ratio" mean Borrower's total Current
Assets divided by Borrower's total Current Liabilities.

     BORROWING BASE CERTIFICATE. Unless waived in writing by Lender, Borrower


                                      -16-
<PAGE>   17
agrees to provide Lender with a Borrower's Certificate within THIRTY (30) days
after the end of each month (if borrowings exceeds $5,000,000.00). Each
"Borrower's Certificate" shall be in a form (Lender form #63-5900) acceptable to
Lender, duly executed by Borrower and detailing the status of the Line of Credit
as of the date thereon.

     AGING AND LISTING OF ACCOUNTS RECEIVABLE AND PAYABLE. Borrower covenants
and agrees with Lender that, while this Agreement is in effect, Borrower shall
deliver to Lender within THIRTY (30) DAYS after the end of each month (if
borrowings exceed $5,000,000.00), a detailed aging of Borrower's accounts and
contracts receivable and accounts payable as of the last day of that month
together with an explanation of any adjustments made at the end of that month,
all in a form acceptable to Lender.

     CUSTOMER LISTING. Borrower agrees with Lender that, while this Agreement is
in effect, Borrower will furnish Lender with, as soon as available after the end
of each fiscal year, a listing of Account Debtors and their addresses, current
as of the year end, in form satisfactory to Lender.

     COLLATERAL AUDITS. Borrower covenants and agrees with Lender that, while
this Agreement is in effect, collateral audits will be performed annually.

     TANGIBLE NET WORTH. Maintain a Minimum Tangible Net Worth of not less than
$44,000,000.00 (step-up by 100% of any new equity).

     INVENTORY REPORTING. Borrower covenants and agrees with Lender that, while
this Agreement is in effect, Borrower shall deliver to Lender after the end of
each month, a schedule of Eligible Inventory to include raw materials at cost
plus scrap value of work in progress and finished goods when borrowings exceed
$5,000,000.00.

     INVESTMENT ACQUISITIONS. Borrower covenants and agrees with Lender that,
while this Agreement is in effect, Borrower shall not, without prior written
consent of Lender, make any Investment Acquisitions over $250,000.00

     PROFITABILITY. Borrower covenants and agrees with Lender that, while this
Agreement is in effect, Borrower shall maintain semi-annual profitability
greater than zero.

     ACCESS LAWS. An exhibit, titled "ACCESS LAWS," is attached to this
Agreement and by this reference is made a part of this Agreement just as if all
the provisions, terms and conditions of the Exhibit had been fully set forth in
this Agreement.

     EVENTS OF DEFAULT. Each of the following shall constitute an Event of
Default under this Agreement:

     Default on Indebtedness. Failure of Borrower to make any payment when due
on the Loans.


                                      -17-
<PAGE>   18
     Other Defaults. Failure of Borrower or any Grantor to comply with or to
perform when due any other term, obligation, covenant or condition contained in
this Agreement or in any of the Related Documents, or failure of Borrower to
comply with or to perform any other term, obligation, covenant or condition
contained in any other agreement between Lender and Borrower.

     Default in Favor of Third Parties. Should Borrower or any Grantor default
under any loan, extension of credit, security agreement, purchase or sales
agreement, or any other agreement, in favor of any other creditor or person that
may materially affect any of Borrower's property or Borrower's or any Grantor's
ability to repay the Loans or perform their respective obligations under this
Agreement or any of the Related Documents.

     False Statements. Any warranty, representation or statement made or
furnished to Lender by or on behalf of Borrower or any Grantor under this
Agreement or the Related Documents is false or misleading in any material
respect at the time made or furnished, or becomes false or misleading at any
time thereafter.

     Defective Collateralization. This Agreement or any of the Related Documents
ceases to be in full force and effect (including failure of any Security
Agreement to create a valid and perfected Security Interest) at any time and for
any reason.

     Insolvency. The dissolution or termination of Borrower's existence as a
going business, the insolvency of Borrower, the appointment of a receiver for
any part of Borrower's property, any assignment for the benefit of creditors,
any type of creditor workout, or the commencement of any proceeding under any
bankruptcy or insolvency laws by or against Borrower.

     Creditor or Forfeiture Proceedings. Commencement of foreclosure or
forfeiture proceedings, whether by judicial proceeding, self-help, repossession
or any other method, by any creditor of Borrower, any creditor of any Grantor
against any collateral securing the Indebtedness, or by any governmental agency.
This includes a garnishment, attachment, or levy on or of any of Borrower's
deposit accounts with Lender.

     Events Affecting Guarantor. Any of the preceding events occurs with respect
to any Guarantor of any of the Indebtedness or any Guarantor dies or becomes
incompetent, or revokes or disputes the validity of, or liability under, any
Guaranty of the Indebtedness.

     Change in Ownership. Any change in ownership of twenty-five percent (25%)
or more of the common stock of Borrower.

     Adverse Change. A material adverse change occurs in Borrower's financial
condition, or Lender believes the prospect of payment or performance of the
Indebtedness is impaired.

     EFFECT OF AN EVENT OF DEFAULT. If any Event of Default shall occur, except
where otherwise provided in this Agreement or the Related Documents, all
commitments and 


                                      -18-
<PAGE>   19
obligations of Lender under this Agreement or the Related Documents or any other
agreement immediately will terminate (including any obligation to make Loan
Advances or disbursements), and, at Lender's option, all Indebtedness
immediately will become due and payable, all without notice of any kind to
Borrower, except that in the case of an Event of Default of the type described
in the "Insolvency" subsection above, such acceleration shall be automatic and
not optional. In addition, Lender shall have all the rights and remedies
provided in the Related Documents or available at law, in equity, or otherwise.
Except as may be prohibited by applicable law, all of Lender's rights and
remedies shall be cumulative and may be exercised singularly or concurrently.
Election by Lender to pursue any remedy shall not exclude pursuit of any other
remedy, and an election to make expenditures or to take action to perform an
obligation of Borrower or of any Grantor shall not affect Lender's right to
declare a default and to exercise its rights and remedies.

     MISCELLANEOUS PROVISIONS. The following miscellaneous provisions are a part
of this Agreement:

     Amendments. This Agreement, together with any Related Documents,
constitutes the entire understanding and agreement of the parties as to the
matters set forth in this Agreement. No alteration of or amendment to this
Agreement shall be effective unless given in writing and signed by the party or
parties sought to be charged or bound by the alteration or amendment.

     APPLICABLE LAW. THIS AGREEMENT HAS BEEN DELIVERED TO LENDER AND ACCEPTED BY
LENDER IN THE STATE OF CALIFORNIA. IF THERE IS A LAWSUIT, BORROWER AGREES UPON
LENDER'S REQUEST TO SUBMIT TO THE JURISDICTION OF THE COURTS OF SACRAMENTO
COUNTY, THE STATE OF CALIFORNIA. THIS AGREEMENT SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF CALIFORNIA.

     Caption Headings. Caption headings in this Agreement are for convenience
purposes only and are not to be used to interpret or define the provisions of
this Agreement.

     Multiple Parties; Corporate Authority. All obligations of Borrower under
this Agreement shall be joint and several, and all references to Borrower shall
mean each and every Borrower. This means that each of the persons signing below
is responsible for ALL obligations in this Agreement.

     Consent to Loan Participation. Borrower agrees and consents to Lender's
sale or transfer, whether now or later, of one or more participation interests
in the Loans to one or more purchasers, whether related or unrelated to Lender.
Lender may provide, without any limitation whatsoever, to any one or more
purchasers, or potential purchasers, any information or knowledge Lender may
have about Borrower or about any other matter relating to the Loan, and Borrower
hereby waives any rights to privacy it may have with respect to such matters.
Borrower additionally waives any and all notices of sale of participation
interests, as well as all notices of any repurchase of such participation
interests. Borrower also agrees that the purchasers of any such participation
interests will be considered as the absolute owners of such interests in the
Loans and will have all the rights granted under the participation agreement or


                                      -19-
<PAGE>   20
agreements governing the sale of such participation interests. Borrower further
waives all rights of offset or counterclaim that it may have now or later
against Lender or against any purchaser of such a participation interest and
unconditionally agrees that either Lender or such purchaser may enforce
Borrower's obligation under the Loans irrespective of the failure or insolvency
of any holder of any interest in the Loans. Borrower further agrees that the
purchaser of any such participation interests may enforce its interests
irrespective of any personal claims or defenses that Borrower may have against
Lender.

     Costs and Expenses. Borrower agrees to pay upon demand all of Lender's
expenses, including without limitation attorneys' fees, incurred in connection
with the preparation, execution, enforcement, modification and collection of
this Agreement or in connection with the Loans made pursuant to this Agreement.
Lender may pay someone else to help collect the Loans and to enforce this
Agreement, and Borrower will pay that amount. This includes, subject to any
limits under applicable law, Lender's attorneys' fees and Lender's legal
expenses, whether or not there is a lawsuit, including attorneys' fees for
bankruptcy proceedings (including efforts to modify or vacate any automatic stay
or injunction), appeals, and any anticipated post-judgment collection services.
Borrower also will pay any court costs, in addition to all other sums provided
by law.

     Notices. All notices required to be given under this Agreement shall be
given in writing, may be sent by telefacsimile (unless otherwise required by
law), and shall be effective when actually delivered or when deposited with a
nationally recognized overnight courier or deposited in the United States mail,
first class, postage prepaid, addressed to the party to whom the notice is to be
given at the address shown above. Any party may change its address for notices
under this Agreement by giving formal written notice to the other parties,
specifying that the purpose of the notice is to change the party's address. To
the extent permitted by applicable law, if there is more than one Borrower,
notice to any Borrower will constitute notice to all Borrowers. For notice
purposes, Borrower will keep Lender informed at all times of Borrower's current
address(es).

     Severability. If a court of competent jurisdiction finds any provision of
this Agreement to be invalid or unenforceable as to any person or circumstance,
such finding shall not render that provision invalid or unenforceable as to any
other persons or circumstances. If feasible, any such offending provision shall
be deemed to be modified to be within the limits of enforceability or validity;
however, if the offending provision cannot be so modified, it shall be stricken
and all other provisions of this Agreement in all other respects shall remain
valid and enforceable.

     Subsidiaries and Affiliates of Borrower. To the extent the context of any
provisions of this Agreement makes it appropriate, including without limitation
any representation, warranty or covenant, the word "Borrower" as used herein
shall include all subsidiaries and affiliates of Borrower. Notwithstanding the
foregoing however, under no circumstances shall this Agreement be construed to
require Lender to make any Loan or other financial accommodation to any
subsidiary or affiliate of Borrower.


                                      -20-
<PAGE>   21
     Successors and Assigns. All covenants and agreements contained by or on
behalf of Borrower shall bind its successors and assigns and shall inure to the
benefit of Lender, its successors and assigns. Borrower shall not, however, have
the right to assign its rights under this Agreement or any interest therein,
without the prior written consent of Lender.

     Survival. All warranties, representations, and covenants made by Borrower
in this Agreement or in any certificate or other instrument delivered by
Borrower to Lender under this Agreement shall be considered to have been relied
upon by Lender and will survive the making of the Loan and delivery to Lender of
the Related Documents, regardless of any investigation made by Lender or on
Lender's behalf.

     Time Is of the Essence. Time is of the essence in the performance of this
Agreement.

     Waiver. Lender shall not be deemed to have waived any rights under this
Agreement unless such waiver is given in writing and signed by Lender. No delay
or omission on the part of Lender in exercising any right shall operate as a
waiver of such right or any other right. A waiver by Lender of a provision in
this Agreement shall not prejudice or constitute a waiver of Lender's right
otherwise to demand strict compliance with that provisions or any other
provision of this Agreement. No prior waiver by Lender, nor any course of
dealing between Lender and Borrower, or between Lender and any Grantor, shall
constitute a waiver of any of Lender's rights or of any obligations of Borrower
or of any Grantor as to any future transactions. Whenever the consent of Lender
is required under this Agreement, the granting of such consent by Lender in any
instance shall not constitute continuing consent in subsequent instances where
such consent is required, and in all cases such consent may be granted or
withheld in the sole discretion of Lender.

     BORROWER ACKNOWLEDGES HAVING READ ALL THE PROVISIONS OF THIS LOAN
AGREEMENT, AND BORROWER AGREES TO ITS TERMS. THIS AGREEMENT IS DATED AS OF
SEPTEMBER 18, 1998.


BORROWER:

AMERICAN XTAL TECHNOLOGY

By:   /s/ MORRIS S. YOUNG 
      -------------------------------------------------
      Authorized Officer         (Title)


                                      -21-
<PAGE>   22
LENDER:

U.S. BANK NATIONAL ASSOCIATION

By:   /s/ JASON FLOYD
      -------------------------------------------------
      Authorized Officer


                                      -22-