<PAGE>

                                                                 EXHIBIT 10.21

                                      UMC


                               Foundry Agreement


                                    Between



                      United Microelectronics Corporation



                                      And



                        Centillium Communications, Inc.
<PAGE>

                               FOUNDRY AGREEMENT
                               -----------------

This Foundry Agreement (the "Agreement") is entered into this March 7th , 2000
(the "Effective Date") by and between Centillium Communications Inc., a
corporation having its principal place of business at 47211 Lakeview Blvd.,
Fremont, California, 94538 ("Buyer") and UMC Group (USA), a California
corporation having its principal place of business at 488 DeGuigne Drive,
Sunnyvale, California, 94086 ("Seller"), for provision of foundry services to be
performed by United Microelectronics Corporation, an ROC corporation
("Manufacturer").

                                   RECITALS

A.  WHEREAS, Seller is in the business of furnishing integrated circuit
manufacturing services performed by Manufacturer, which shall perform, at
Seller's request, the manufacturing services contracted for with Seller
hereunder;

B.  WHEREAS, Buyer desires to have Seller furnish integrated circuit
manufacturing services for it;

NOW, THEREFORE, in consideration of the following covenants and conditions the
parties agree:

1  DEFINITIONS

1.1  "Products" shall mean the products to be manufactured pursuant to this
      --------
     Agreement as specified in Quotation(s).

1.2  "Quotation(s)" shall mean the quotations attached hereto under Exhibit a
      ------------
     and such further quotations as are agreed upon in a writing signed by Buyer
     and an Officer of Seller. Each such Quotation shall describe the Products
     to be manufactured, prices, fees and charges for the Products, acceptance
     criteria for Products, all aspects of, and services needed for, mask
     making, testing, assembly and packaging, and all other specifications,
     quantities, cycle and lead times and parameters for the Products. Prices
     shall be separately itemized for mask sets, processed wafers, wafer probe,
     assembly and final test.

2  PRODUCTION PROCEDURES

2.1  Product Prototype Approval. No Product prototypes shall be manufactured
     --------------------------
     except pursuant to a Quotation approved in writing by Buyer and an Officer
     of Seller. For each Quotation for a new Product agreed upon by the parties,
     Buyer will deliver a tape in GDS II format or a mask set. If Buyer provides
     its design in the form of a tape, then upon receipt of the tape from Buyer,
     Seller, or its subcontractors, will produce a mask set. In either case,
     Seller will produce one or more pilot wafer runs according to the schedule
     and at the price set forth in the Quotation. Within ninety
<PAGE>

     (90) days after receipt of pilot run wafers for a new Product, Buyer may
     return any claimed non-conforming pilot wafers to Seller with a written
     rejection statement specifying the alleged failure or failures of the pilot
     wafers to meet the Acceptance Criteria set forth in the Quotation. If Buyer
     does not return the pilot wafers with a written rejection statement within
     such ninety (90) day period, then the process and pilot wafers shall be
     deemed to have been approved by Buyer. If any pilot wafer does not meet the
     Acceptance Criteria for reasons attributable to Seller and is rejected by
     Buyer, Seller shall at Seller's expense use commercially reasonable efforts
     to rerun the pilot wafers and resubmit the results in a manner that
     complies with the Acceptance Criteria. If Seller, within ninety (90) days
     after receipt of Buyer's timely written rejection report, is unable to
     supply Buyer with conforming pilot wafers, then either party may by written
     notice to the other terminate this Agreement as to such Product and
     Quotation, and if so terminated, Buyer will not owe Seller any amounts for
     the pilot wafers involved (1) otherwise provided in the Quotation, or (2)
     the noncompliance was attributable to Seller.

2.2  ECNs
     ----

2.2.1  Buyer ECNs. After initial qualification, Buyer shall have the right to
       ----------
     make such changes as it deems appropriate to the design of Products to be
     fabricated for it by Seller, provided however that each such change must be
     timely documented by Buyer through written change notices. Notwithstanding
     anything to the contrary, after process qualification runs for a particular
     design have been made and approved by Seller and Buyer, any Buyer-requested
     changes to design, process or materials for such Products shall be subject
     to Seller's consent (which will not be unreasonably withheld) and payment
     by Buyer of applicable reasonable costs, if any, related to such change.

2.2.2  Seller ECNs. For changes that Seller desires to make, the following
       -----------
     procedure shall apply:

2.2.2.1  Routine Changes. Seller may, with Buyer's prior written approval, which
         ---------------
     may not unreasonably be withheld, make changes in the processes used to
     manufacture Products (i) that do not materially affect physical or
     functional interchangeability or performance; or (ii) when required for
     purposes of safety and/or compliance with applicable law or regulations.

2.2.2.2 Material Changes.
        -----------------

2.2.2.2.1  Seller shall give Buyer advance written notice of any proposed
      change(s) ("Proposed Change Notice") in materials and/or to the
      manufacturing processes qualified for production of Products, which, to
      the best of Seller's knowledge, might affect the form, fit, performance,
      maintainability, operation, function, reliability, interface,
      interconnectability, compatibility, design rules, models, or size of the
      chips for Products then qualified and subject to open purchase orders from
      Buyer.
<PAGE>

2.2.2.2.2  Such Proposed Change Notice shall describe the nature of the proposed
           change(s), including reasons for the change(s), the anticipated
           schedule for implementation of the change(s), and other relevant
           technical and logistic considerations, including without limitation
           quality and reliability data to the extent available.

2.2.2.2.3  Buyer shall approve or disapprove any such proposed change promptly,
           but in no event may any such change be disapproved later than five
           (5) business days after receipt of the Proposed Change Notice.

2.2.2.2.4  If Buyer disapproves such proposed change within the five business
           day period allowed, Seller shall continue to manufacture and deliver
           to Buyer unchanged Products in accordance with the applicable
           Agreements for a minimum of six (6) months from the date Seller
           issues the Proposed Change Notice.

2.2.2.2.5  Upon the expiration of three months after the following Proposed
           Change Notice, Seller, in its discretion and by then giving a minimum
           of three months prior written notice to the Buyer, may stop
           manufacture and delivery of all Products involved without liability.

2.2.3      Quality Assurance. No additional quality assurance requirements or
           -----------------
           measurements (whether cv plots, metal step coverage analysis, SEM
           analysis, or other) will be required except upon Seller's written
           agreement as to the step or measurement to be performed, and Buyer's
           written commitment to pay Seller's stated costs.

2.3  Production Runs, Pilot Runs, Hot Runs, etc. Exhibits a and B set forth the
     ------------------------------------------
     terms applicable to Wafer Cycle Time, Pilot Runs, Hot Lots, Production Runs
     and On Hold.

3  ORDER, DELIVERY, PRICING AND PAYMENT TERMS

3.1  Forecasts
     ---------

3.1.1   During the first seven calendar days of each month, Buyer will provide
        to Seller by facsimile or other electronic communication a written
        rolling forecast of its wafer capacity requirements from Seller's
        facilities for the next twelve full calendar months (each a "Buyer
        Forecast") (provided however that forecasts for the seventh and later
        months are for reference only and not binding on either party).

3.1.1.1  Each such Buyer Forecast shall show the quantity of wafer outs and the
         specific technology and/or process for the wafers listed. Buyer shall
         make good faith efforts to ensure that all such Buyer Forecasts are
         reasonable estimates of its anticipated needs. Subject to this
         obligation, and except as expressly stated in this Section 3.1.1 and/or
         in a written capacity quotation, all such Buyer
<PAGE>

      Forecasts (and any responses to them) will be for planning purposes only,
      and will not create any obligation to purchase and/or sell.

3.1.1.2  Each such Buyer Forecast shall constitute a commitment by the Buyer to
     purchase a minimum of the following percentages of the amounts indicated:

<TABLE>
<CAPTION>
---------------------------------------------------------------------------------------------------------
Month in the forecast      First month     Second month of     Third month   Fourth month   Fifth & sixth
                           of forecast         forecast        of forecast    of forecast       months
---------------------------------------------------------------------------------------------------------
<S>                        <C>           <C>                   <C>           <C>            <C>
Minimum percentage
commitment for                     100%                  100%          100%            75%             50%
amounts forecast for
that month
---------------------------------------------------------------------------------------------------------
</TABLE>

3.1.1.3  Seller will provide a written response to each Buyer forecast within
     two weeks of Seller's receipt. Subject to Section 3.1.2 below and the other
     terms set forth in this Agreement, Seller's response shall accept the
     quantities in the applicable months to the extent they are less than or
     equal to those accepted by Seller for the applicable month(s) pursuant to
     prior written agreement and/or forecasts. Seller's response may accept
     and/or reject in whole or in part any additional forecast quantities for
     those months.

3.1.2  To the extent that any forecast from Buyer pursuant to Section 3.1.1
     above fails to forecast the full capacity or quantity if any, allocated or
     promised to Buyer during any one or more of the first twelve months of such
     forecast: (i) Seller shall be entitled in its sole and complete discretion
     to enter commitments with others for such unexercised capacity for the
     applicable months and in the amounts not so exercised, and (ii) such Buyer
     will not have any right to require Seller to provide that unexercised
     capacity to that Buyer in the month(s) involved.

3.2  Orders And Production Release. No order for production quantities of a
     -----------------------------
     Product shall be placed by Buyer unless and until Buyer has approved the
     pilot runs or prototypes for the Product. If Buyer properly places an order
     for production quantities of a Product, Seller may deem such an order as
     written production release approval for such Product. All orders for
     Products shall be in writing. Seller shall acknowledge in writing, within
     three (3) business days of receipt of an order, either the acceptance of
     the order, or the reason such order cannot be accepted, or if Seller wishes
     to modify such order. If Seller does not provide such acknowledgement
     within the time provided, Buyer shall contact Seller to determine the cause
     for the lack of acknowledgment. No acceptance of a purchase order shall
     constitute acceptance of any terms at variance with this Agreement and/or
     previously agreed forecasts, and purchase orders shall be null and void as
     to those variances.

3.3  Cancellation and Modifications to Orders.
     -----------------------------------------

3.3.1  Cancellations and Modifications. Unless wafer processing has started, or
       -------------------------------
     Seller has incurred engineering or tooling charges, Buyer may cancel or
     modify a
<PAGE>

     purchase order without penalty by delivering to Seller a written notice of
     cancellation or modification within three (3) days of Seller's receipt of
     the original purchase order involved; provided however that no such
     cancellation will relieve Buyer of any obligations under any other
     applicable provisions or agreements including without limitation any
     obligation to comply with loading commitments, forecasts and/or purchase
     orders.

3.3.2  Cancellation Charges. In addition to, and without waiving any other
       --------------------
     remedies, the minimum charges for order cancellation shall be the contract
     price multiplied by the proportion of the relative mask step at which the
     wafer(s) were at the time of cancellation, plus all costs of starting wafer
     materials and mask sets.

3.3.3  Partially Completed Products. In no event will Buyer have rights in
       ----------------------------
     partially completed Products.

3.4  Delivery.
     --------

3.4.1  Delivery will be made FCA (Incoterms 2000), Manufacturer's plant, Science
     Based Industrial Park, HsinChu City, Taiwan, to a carrier designated in
     writing by Buyer or, if Buyer fails to designate a carrier, to a carrier
     designated by Seller.

3.4.2  Title to the Products will pass to Buyer upon delivery to carrier.

3.4.3  All shipping and delivery dates are subject to timely receipt of fully-
     approved mask sets and fully-completed purchase orders in the HsinChu
     office of Manufacturer's fab where the wafers are to be processed.

3.4.4  Seller shall make reasonable efforts to achieve on-time delivery and
     linear shipments. Subject to this and Seller's written commitments for
     wafer starts, SELLER SHALL NOT BE LIABLE FOR ANY DELAYS OR FAILURES TO MEET
     DATES.

3.4.5  In the event of any delays and/or any breach of any written warranty,
     Buyer may give prompt written notice to Seller, adjusting forecasted and/or
     ordered amounts, and/or canceling orders for affected Products, to the
     extent necessary as a result of any impact of such delay on Buyer's need
     for such Products.

3.5 Pricing.
-----------

3.5.1  Refer to Exhibit A.02 for Pricing. Exhibit A.02 shall be reviewed on a
     yearly basis and pricing may be revised if needed. Such review shall be
     done during the last quarter of each year to set prices for the following
     year.

3.5.2  Any tax or related charge which Seller shall be required to pay to or
     collect for any government upon or with respect to services rendered or the
     sale, use or delivery of the Product or other materials (except for taxes
     based on Seller's
<PAGE>

     income) shall be billed to the Buyer as a separate item and paid by Buyer,
     unless a valid exemption certificate is furnished by Buyer to Seller.

3.6  Payment
     -------

3.6.1  Unless otherwise agreed or stated in Seller's quotation, full payment
     shall be made in New Taiwan Dollars or U.S. Dollars (as stated in the
     applicable Quotation or as otherwise agreed in writing) within 30 days of
     delivery.

3.6.2  Seller reserves the right to change credit terms at any time in its
     reasonable discretion.

3.6.3  Buyer will issue written purchase orders at least four weeks, plus the
     agreed cycle time, prior to requested wafer out day.

3.6.4  Regardless of anything to the contrary, Buyer understands that Seller
     generally needs to start more than the numbers of wafers ordered by Buyer
     in order to guarantee the quantities of wafers so ordered which will yield
     within the agreed specifications. Accordingly, Buyer will accept quantity
     variations (and pay according to the agreed pricing) up to as much as ten
     percent (10%) above the quantities stated in Buyer's purchase order(s).

4  RELIABILITY & QUALITY

4.1  Quality Data. Seller will provide, upon Buyer's written request during the
     ------------
     term of their foundry relationship, Seller's available reliability and
     quality data regarding Products produced for Buyer for the purpose of
     maintaining consistent quality and reliability standards for such Products.

4.2  Traceability. During the term of the foundry relationship, Seller shall
     ------------
     maintain fab and test lot traceability for Products manufactured on behalf
     of Buyer.

4.3  Notification of Defects. Seller will promptly after discovery advise Buyer
     -----------------------
     of defects and/or non-conformity in Products already shipped to and/or in
     lots currently in manufacture for Buyer.

4.4  Acceptance Criteria. Wafer acceptance will be subject to process control
     -------------------
     monitor acceptance criteria to be mutually agreed upon on a process-by-
     process basis. Once approved, no such wafer acceptance criteria shall be
     binding until in a writing signed by an Officer of Seller which clearly and
     specifically identifies the Products (by mask or product number) and
     processes (by Seller's process designation) involved. All accept/reject
     criteria shall be stated in the agreed upon wafer acceptance and visual
     inspection specifications and all critical dimension and process tolerances
     shall be solely as agreed upon in writing.
<PAGE>

4.5  Stop Shipments.
     --------------

4.5.1  Subject to Buyer's obligations with respect to volumes committed under
     the ordering and forecasting procedures involved, upon receipt of Buyer's
     written Stop Request, Seller will immediately stop shipment of Products
     which are subject to a suspected failure to meet the criteria specified in
     the wafer acceptance criteria agreed upon in writing between Buyer and
     Seller. If Seller is responsible for such failure, and Seller is not able
     to correct the matter within sixty (60) days of receipt of such Stop
     Notice, then (i) Buyer may reject non-conforming Products, and, (ii) Buyer
     may, without penalty (including loss of capacity), cancel any then-pending
     purchase order(s) for such Products as to which Wafers have not been
     started by sending written notice of cancellation to Seller within seventy-
     five (75) days of the written Stop Request. Such a notice of cancellation
     shall be effective on receipt by Seller.

4.5.2  If Buyer requests Seller to stop shipment of any Products which Buyer is
     obligated to purchase, and the Products are determined in good faith by
     Seller to have been processed in accordance with the applicable written
     requirements, in addition to and without waiving any other remedies, Buyer
     shall pay Seller in full for completed Products and, in addition, for
     Seller's reasonable costs for work in progress. Under this Section 4.5
     payment for completed Products will be at the purchase order price, and
     payment for work in progress shall be based on Buyer's actual costs for raw
     materials and the relative mask step reached when work is stopped.

4.6  Failure Analysis. Upon written request from Buyer and subject to
     ----------------
     satisfactory arrangements for payment to Seller for the reasonable costs
     involved, Seller will perform failure analysis of Products returned to
     Seller pursuant to Seller's standard Return Policy and Procedures. If such
     analysis shows the existence of material defects in breach of applicable
     Seller warranties, Seller will not be entitled to payment for the cost of
     Seller's failure analysis concerning such defects for the specific Products
     which were subject to them.

4.7  Return Material Authorization (RMA). Buyer will not make any returns to
     -----------------------------------
     Seller without first obtaining a written Return Material Authorization
     (RMA). Buyer agrees to pay Seller the full purchase price and all costs and
     charges incurred by Seller in connection with any returned wafers or
     Products which Seller determines were within Seller's specifications at the
     time of initial delivery to the carrier or at the time of return to Seller.
     Generally, Seller will analyze authorized returns within four (4) working
     weeks of receipt by Seller, and promptly thereafter report on the results.
     Buyer agrees to cooperate in good faith with Seller to resolve any problems
     that may arise and to promptly send Seller the results of all tests and
     analyses concerning Products.

5  WARRANTY
<PAGE>

5.1  Limited Warranty. Seller warrants Products delivered after initial
     ----------------
     qualification shall be processed (i) using the masks (or duplicates of
     them) which were used for qualification, (ii) within the tolerances stated
     in Seller's applicable process specifications, and (iii) in compliance with
     applicable Wafer Acceptance and/or Yield Criteria agreed to in a writing
     signed by Seller and Buyer.

5.2  Exclusions.
     ----------

5.2.1  Products which have been subject to abuse, misuse, accident, alteration,
     neglect, conditions outside specification, unauthorized repair or improper
     application are not covered by any warranty.

5.2.2  Seller shall not be responsible for defects or claims caused by acts not
     performed by Seller; or by design or application; or by combination of
     Products with other things.

5.2.3  Products are not intended for use in, and no warranty is made with
     respect to, applications where failure to perform can reasonably be
     expected to result in significant injury (including, without limitation,
     navigation, weaponry, aviation or nuclear equipment, or for surgical
     implant or to support or sustain life) and Buyer will indemnify, defend,
     and hold harmless Seller from all claims, damages and liabilities arising
     out of any such matters.

5.3  Remedy. To the extent that any Products fail to meet the applicable
     ------
     warranties and/or requirements due to reasons for which Seller is
     responsible, Seller shall either (i) replace such Products without charge,
     or (ii) refund the payments made to Seller for such Products, all within
     sixty (60) calendar days of Seller's receipt of written notice from Buyer
     of such non-conformity. The parties will discuss in good faith which of
     these two remedies is the most appropriate; provided however that if they
     cannot agree, Seller may choose in its sole discretion between the two
     remedies, and provided further that all Products for which refund and/or
     replacement is sought and all returns shall be handled pursuant to Seller's
     Return Policy and Procedures.

5.4  Sole Warranty. This Section 5 is the only warranty by or on behalf of
     -------------
     Seller and may not be modified or amended except in writing signed by an
     authorized officer of Seller and by Buyer. Buyer is not relying upon any
     warranty or representation except for those specifically stated here or in
     such a signed writing. With respect to obligations of Seller under this
     Agreement which would logically be undertaken and/or performed by
     Manufacturer, Seller guarantees Manufacturer's performance thereof.

5.5  No Reliance. Buyer is not relying on any statements or information in
     -----------
     Seller's literature, and Buyer will test all parts and applications under
     extended field and laboratory conditions as appropriate. Notwithstanding
     any cross-reference or statements of compatibility, functionality,
     interchangeability, and the like, Seller
<PAGE>

     made goods, embedded devices and processes may differ from similar goods,
     devices and processes from other vendors in performance, function or
     operation, or as to matters, ranges and conditions not stated in and/or
     outside Seller's written specifications; and Buyer agrees that Seller makes
     no warranties and is not responsible for such things. All reusable IP,
     including that listed in Seller's Intellectual Property Catalog, and
     including but not limited to blocks, libraries, tools, and documentation
     therefor, is licensed to Buyer by the individual IP vendors and not by
     Seller, and in any event Seller makes no warranty in connection with such
     IP. Buyer is not relying on any statements or information provided by
     Seller in connection with such IP, and Buyer will fully verify all IP as
     appropriate and be responsible to ensure that such IP is compatible and
     suitable for Buyer's intended purpose and applications.

5.6  Disclaimer. EXCEPT AS PROVIDED ABOVE, SELLER MAKES NO WARRANTIES OR
     ----------
     CONDITIONS, EXPRESS, IMPLIED, OR STATUTORY, AND EXPRESSLY EXCLUDES AND
     DISCLAIMS ANY WARRANTY OR CONDITION OF MERCHANTABILITY, NONINFRINGEMENT, OR
     FITNESS FOR a PARTICULAR PURPOSE OR APPLICATION.

5.7  Limitation. REGARDLESS OF CAUSE OR REASON FOR DAMAGE (WHETHER ACCIDENT,
     ----------
     NEGLIGENCE, OR OTHERWISE) SELLER SHALL HAVE NO LIABILITY (DIRECT,
     CONSEQUENTIAL OR OTHER) FOR, IN CONNECTION WITH OR ARISING FROM PROPERTY
     FURNISHED FOR USE AT OR LEFT AT SELLER; and by delivering or entrusting
     property to Seller, Buyer expressly confirms this limitation.
     Notwithstanding this limitation, Seller will replace, or pay the reasonable
     retooling costs to replace, masks damaged or destroyed as a result of
     Seller's negligence or fault. Upon written request sent to the billing
     address listed on Buyer's latest-dated purchase order, Buyer will promptly
     take possession of any and all property of Buyer, and should Buyer fail to
     do so within thirty days of such request, Seller may destroy or reclaim
     such property without liability.

6  LIMITATION OF LIABILITY

6.1  Force Majeure. Neither party will be liable for any loss, damage or claim
     -------------
     resulting from causes beyond its reasonable control, including but not
     limited to, war, fire, delay caused by others, material shortage, force
     majeure, or labor conditions; and in the event of such a condition(s), the
     date(s) for Seller's performance will be extended for a period equal to any
     resulting delay.

6.2  Limitation of Liability.
     ------------------------

6.2.1  SELLER'S LIABILITY ARISING OUT OF ANY QUOTATION, ANY AGREEMENT, ANY
     BREACH THEREOF, OR ANY PRODUCTS OR SERVICES WILL BE LIMITED TO REFUND OF
     THE PURCHASE PRICE
<PAGE>

     OR REPLACEMENT OF PURCHASED PRODUCTS (RETURNED TO SELLER FREIGHT PREPAID);
     OR 1N THE EVENT OF a FAILURE OR BREACH BY SELLER REGARDING DELIVERY, AN
     AMOUNT EQUAL TO THE TOTAL PURCHASE PRICE OF THE PRODUCTS THAT HAVE NOT BEEN
     DELIVERED DUE TO SUCH FAILURE. ALL CLAIMS WILL BE SUBJECT TO THE TIME
     LIMITATIONS STATED IN SELLER'S RETURN POLICY AND PROCEDURE.

6.2.2  AS a SEPARATE LIMITATION, IN NO EVENT WILL SELLER BE LIABLE (i) FOR COSTS
     OF SUBSTITUTE PRODUCTS, (ii) FOR ANY SPECIAL, CONSEQUENTIAL, INCIDENTAL OR
     INDIRECT DAMAGES, OR (iii) FOR LOSS OF USE, OPPORTUNITY, MARKET POTENTIAL,
     GOODWILL AND/OR PROFIT ON ANY THEORY (CONTRACT, TORT, FROM THIRD PARTY
     CLAIMS OR OTHERWISE). THESE LIMITATIONS SHALL APPLY NOTWITHSTANDING ANY
     FAILURE OF ESSENTIAL PURPOSE OR OF ANY FAILURE OR INADEQUACY OF ANY REMEDY.
     THIS AGREEMENT STATES THE ONLY AND EXCLUSIVE REMEDY FOR ANY AND ALL CLAIMS
     MADE AGAINST SELLER UNDER ANY AGREEMENT AND/OR WITH RESPECT TO WAFERS,
     SERVICES AND/OR PRODUCTS.

6.3  Commencement of Actions or Proceedings. No action or proceeding (except for
     --------------------------------------
     payment for delivered Products) may be commenced by either party against
     the other, whether for breach, indemnification, contribution or otherwise,
     more than one year after delivery of the Products to the carrier; and no
     claim may be brought unless the non-claiming party has first been given
     commercially reasonable notice, a full written explanation of all pertinent
     details (including copies of all materials), and a good faith opportunity
     to resolve the matter.

6.4  BUYER EXPRESSLY AGREES TO THE LIMITATIONS OF SECTIONS 5, 6, 7 AND 8 AND TO
     THEIR REASONABLENESS.

7  INDEMNIFICATION & COOPERATION

7.1  Indemnification by Seller. Seller will defend and/or settle all suits
     -------------------------
     against Buyer to the extent based on any claim that any processes (as
     performed by Seller with respect to Products) infringe any R.O.C.,
     Canadian, Japanese, European Community and/or U.S. patent, copyright, trade
     secret or trademark; provided, however, that Buyer (i) gives immediate
     written notice to Seller, (ii) permits Seller to defend, and (iii) gives
     Seller all needed information, assistance, and authority.

7.2  Exclusions. Seller will not be responsible for infringements resulting from
     ----------
     anything not manufactured entirely by Seller. or from any combination with
     things or materials not furnished by Seller, or for any claim due in whole
     or in part to any act, omission, design and/or specification of Buyer.
<PAGE>

7.3  THIS ARTICLE 7 STATES SELLER'S ENTIRE LIABILITY AND OBLIGATION WITH RESPECT
     TO INTELLECTUAL PROPERTY INFRINGEMENT OR CLAIMS THEREFOR AND IS EXPRESSLY
     SUBJECT TO ARTICLE 6. Except as to claims Seller is obligated to defend
     and/or resulting from Seller's wrongdoing and/or negligence, BUYER WILL
     INDEMNIFY, DEFEND AND HOLD HARMLESS SELLER FROM ALL CLAIMS, COSTS, LOSSES,
     AND DAMAGES (INCLUDING REASONABLE ATTORNEYS' FEES) AGAINST AND/OR ARISING
     OUT OF PRODUCTS AND/OR SERVICES.

7.4  Buyer Guarantee and Indemnity. Without limiting any other terms, Buyer
     -----------------------------
     guarantees that production of Products pursuant to Buyer's specifications
     and/or designs will not infringe, misappropriate or violate any applicable
     R.O.C., Canadian, Japanese, European Community and/or U.S. copyright,
     trademark, patent, trade secret, mask work, or other rights of third
     parties. In the event Buyer becomes party to any infringement or
     misappropriation action or dispute with respect to Products, (i) Seller
     may, at its sole option, immediately terminate and/or suspend performance,
     and (ii) Buyer shall be fully and solely responsible, and will defend,
     indemnify and hold Seller harmless from any and all damages, losses and
     costs (including Seller's reasonable attorneys fees) resulting from any
     claimed breach of Buyer's guarantee.

7.5  Cooperation. Seller and Buyer will cooperate in connection with any issue
     -----------
     raised with respect to intellectual property rights of third parties
     relating to goods and/or to services under this Agreement. Without limiting
     the foregoing, upon written notice to the other, any Party may suspend (i)
     performance of its obligations, (ii) exercise of its rights of first
     refusal with respect to capacity and/or (iii) providing capacity to the
     extent that such Party has reasonable concerns that its future performance
     in connection with such matters will subject it to claims by others with
     respect to such matters, provided however that no such suspension will
     affect any obligation to pay for Products delivered and/or manufactured in
     whole or in part prior to the date of written notice concerning such
     matters. In the event that Seller exercises any of its rights pursuant to
     this Section 7, Seller will negotiate in good faith to minimize the
     liability of Buyer to others.

8  CONFIDENTIALITY

8.1  NDA. The terms of the Reciprocal Non-Disclosure Agreement, attached hereto
     ---
     as Exhibit C, are expressly incorporated herein.

8.2  Buyer's Masks and Databases. Seller will treat any and all masks and design
     ---------------------------
     databases provided by Buyer as confidential, whether or not they are marked
     as required by Exhibit C.
<PAGE>

8.3  Process Technology. Regardless of anything to the contrary., all processes,
     ------------------
     recipes, and manufacturing, fabrication, assembly and test techniques, and
     related improvements ("process technology") provided and/or developed by or
     on behalf of Seller shall be wholly owned by and the property of Seller,
     and Seller shall not be limited or restricted by this Agreement with
     respect to any process technology unless clearly stated to the contrary in
     a writing signed by an officer of Seller identifying the specific
     information in precise detail.

9  TERMINATION & RELATIONSHIPS

9.1  Term. The term of this Agreement as related to any specific Product covered
     ----
     by this Agreement shall be five (5) years from the date of the Quotation
     for that Product, and shall thereafter be automatically extended for
     additional one (1) year terms, unless and until a party to this Agreement
     gives no less than one (1) year's notice that the term should not be
     further extended for that Product. If Seller gives Buyer notice that the
     terms for a Product will not be extended, then during the one (1). year
     notice period Seller shall continue to accept and fill all orders placed by
     Buyer for commercially reasonable quantities calling for delivery within
     lead time of that Product.

9.2  Termination For Insolvency or Bankruptcy. Subject to Section 9.4 below,
     ----------------------------------------
     Buyer and/or Seller (collectively "the Parties") shall have the right to
     terminate the rights of the other Party under their applicable Agreements
     (and any other agreement concerning Products) by giving written notice of
     termination to that other Party at any time upon or after:

9.2.1  the filing by the other Party of a petition in bankruptcy or insolvency;

9.2.2  any adjudication that the other Party is bankrupt or insolvent;

9.2.3  the filing by the other Party of any petition or answer seeking
     reorganization, readjustment or arrangement of its business under any law
     relating to bankruptcy or insolvency;

9.2.4  the appointment of a receiver for all or substantially all of the
     property of the other Party;

9.2.5  the making by the other Party of any assignment for the benefit of
     creditors; or,

9.2.6  the institution of any proceeding for the liquidation or winding up of
     the other Party's business or for the termination of its corporate charter.

Notwithstanding anything to the contrary, no termination under Section 9.2 as to
such other Party shall affect the rights of the Party giving the notice of
termination with respect to Products delivered and/or as to which production had
begun prior to the effective date of termination. Termination pursuant to this
Section 9.2 shall be effective
<PAGE>

immediately upon personal delivery, of the written notice, or in the case of
airmail notice, five days after dispatch.

9.3  Termination for Breach.
     -----------------------

9.3.1  Termination Events. If any party fails to perform or violates any
       ------------------
     material obligation under the applicable Agreements, effective upon thirty
     (30) days' written notice to the breaching party specifying such default
     (the "Default Notice"), the non-breaching party, may terminate the
     applicable Agreement (and all related agreements concerning Products) as to
     its responsibilities and obligations, without liability (subject to
     Sections 9.4 and 9.5 below), unless:

9.3.1.1  The breach specified in the Default Notice has been cured within the
     thirty (30) day period, or if the breach is disputed, the amount in dispute
     is placed in a reasonably secure third party escrow account pending
     resolution of the dispute;
     or

9.3.1.2  The default reasonably requires more than (30) days to correct
     (specifically excluding any failure to pay money), and the defaulting party
     has begun substantial corrective action to remedy the default within such
     thirty (30) day period and diligently pursues such action, in which event,
     termination shall not be effective unless sixty (60) days has expired from
     the date of the defaulting party's receipt of the Default Notice without
     such corrective action being completed and the default remedied.

9.4  Effect of Termination.
     ----------------------

9.4.1  Termination by Buyer. If Buyer terminates the applicable Agreements for
       --------------------
     any reasons stated in Sections 9.2 and/or 9.3 above, Seller will, if so
     requested in writing by Buyer: (i) cease all production required by Buyer's
     then outstanding purchase orders under the Agreements; and (ii) otherwise
     complete and deliver all Products pursuant to Buyer's then outstanding and
     accepted purchase orders and invoice Buyer for the Products.

9.4.2  Termination by Seller. If Seller terminates this Agreement as to Buyer
       ---------------------
     pursuant to Sections 9.2 and/or 9.3 above, in addition to and without
     waiving any other remedy, Seller shall be entitled to payment in full upon
     delivery of all completed Products manufactured on behalf of Buyer, as well
     as to reimbursement for all reasonable direct costs incurred for up to one
     month's work then in progress for Buyer.

9.5  Survival.
     ---------

9.5.1  All obligations to pay monies which accrue prior to termination and/or
     expiration, and the provisions of the Reciprocal Non Disclosure Agreement
     attached as Exhibit C, as well as all other obligations of confidentiality,
     all limitations on
<PAGE>

     warranties and remedies, all obligations with respect to indemnification
     and cooperation, contribution, dispute resolution, and termination shall
     survive the expiration and/or termination of the applicable Agreements
     and/or of any purchase order or understanding concerning Products.

9.5.2  The exclusions and limitations of Sections 5, 6 and 7 will survive the
     termination of the applicable Agreements, and shall apply notwithstanding
     any claim of a failure of any one or more remedies to accomplish their
     purpose. THE PARTIES EXPRESSLY WAIVE AND RELINQUISH ANY CONTRARY RIGHTS
     UNDER ANY AGREEMENT, AND/OR LAW, DECISION, CUSTOM OR PRACTICE.

10  DISPUTE RESOLUTION

10.1  Management Resolution. Within thirty days of a written demand to meet to
      ---------------------
     resolve such one or more disputes arising out of and/or relating to any
     Agreement and/or Products, senior management with the authority to
     negotiate and resolve the issues shall meet in Taiwan or in some other
     mutually agreeable location to discuss the issues, and, from time to time
     during the forty-five day period following such demand (or longer if
     agreeable to the Parties), such management will negotiate and attempt to
     resolve the issues as reasonably requested by any party involved.

10.2  Arbitration.
      -----------

10.2.1  Any such disputes relating to and/or arising out of any Agreement and/or
     Products which cannot be so resolved will be decided exclusively by binding
     arbitration under procedures which ensure efficient and speedy resolution.
     Such an arbitration may be commenced by Seller and/or Buyer (i) after the
     expiration of the forty-five day period following the written demand to
     meet to resolve the dispute pursuant to Section 10.1 above, and/or (ii) at
     such earlier time as any Party involved repudiates and/or refuses to
     continue with its obligations to negotiate in good faith.

10.2.2  The arbitration hearing will be before a panel of three neutral,
     independent arbitrators. The arbitration hearing will be conducted in Santa
     Clara, California (U.S.A).

10.2.3  The arbitration will be conducted under the International Rules of the
     American Arbitration Association. Notwithstanding anything to the contrary:

10.2.3.1  the arbitrators will have no power to order discovery;

10.2.3.2  the arbitrators will follow such procedures and enter such orders and
       conduct the hearing under conditions which ensure at least the same
       degree of confidentiality for each party as provided by Seller's Standard
       Non-Disclosure Agreement, and which adequately protect the participants
       from disclosure of
<PAGE>

       highly sensitive information to anyone other than the arbitrators and
       lawyers (or comparable legal representatives) and reasonably necessary
       expert witnesses and not to persons employed by one or more of the
       parties nor to competitors of them, and

10.2.3.3  the arbitrators shall require pre-hearing exchange of documentary
       evidence to be relied upon by each of the respective parties in their
       respective cases in chief, and pre-hearing exchange of briefs, witness
       lists and summaries of expected testimony.

10.2.4  The arbitrators will make their decision in writing; and their decision
     will be binding upon the Parties and it may be entered by any court having
     jurisdiction.

10.3  Injunctive Relief. Notwithstanding anything to the contrary, any party may
      -----------------
     apply to any court of competent jurisdiction for interim injunctive relief
     with respect to irreparable harm which cannot be avoided and/or compensated
     by such arbitration proceedings, without breach of this Section 10 and
     without any abridgment of the powers of the arbitrators.

10.4  Governing Law. This Agreement and all foundry arrangements involving
      -------------
     Seller and all performance and disputes arising out of and/or relating to
     such matters and/or any Products involved will be governed by the laws of
     California and the United States of America, without reference to conflicts
     of laws principles, and/or any contrary provision, including without
     limitation, the U.N. Convention on Contracts for the International Sale of
     Goods.

11  GENERAL

11.1  Non-Exclusive Relationship. Except as stated in a separate written
      --------------------------
     agreement signed by duly authorized officers of Seller and of Buyer,
     nothing in the Agreements shall prohibit Buyer from purchasing goods and/or
     foundry services from other suppliers, nor prohibit Seller from offering
     wafers and/or foundry services to others or from offering products or
     services on its own behalf.

11.2  No Agency or Partnership. Nothing in the Agreements shall be deemed to
      ------------------------
     create a general or limited partnership or an agency relationship between
     Buyer and/or Seller, and Buyer and Seller are independent companies. Buyers
     will purchase products manufactured from Seller in an arm's length vendor-
     purchaser relationship. No party shall be entitled to act on behalf of
     and/or to bind any one or more of the others.

11.3  Compliance with Law. The parties will comply with all applicable
      -------------------
     restrictions and requirements of applicable law, including without
     limitation those relating to labor, employment, environment, and export
     control. Buyer agrees at its sole expense to comply with all applicable
     laws in connection with the purchase, use or sale of the Products.
<PAGE>

11.4  No Implied Licenses. Nothing contained in this Agreement is intended to or
      -------------------
     shall be construed as:

11.4.1  conferring any right to the other Party to use in advertising,
     publicity, or otherwise, any trademark, trade name or names of any Party,
     or any contraction, abbreviation or simulation thereof; and/or

11.4.2  conferring by implication, estoppel or otherwise, upon any Party any
     license or other right under any class or type of copyright, maskwork,
     trademark, trade name, patent, utility, model or design patent except the
     licenses and rights expressly granted under a written agreement signed by
     the Parties.

11.5  Entire Agreement. This Agreement (including the attached exhibits)
      ----------------
     contains all material and essential terms of a binding agreement between
     the parties with respect to with respect to foundry., fabrication,
     semiconductors, design support and goods, there are no other agreements
     concerning such subject matter. This Agreement is the entire agreement
     between the parties with respect to the stated subject matter; it
     supersedes all prior understandings and agreements with respect to these
     matters, and there are no prior representations, warranties or other
     agreements relating thereto. This Agreement may not be modified, except in
     writing signed by duly authorized officer of each party, and no addition,
     deletion or modification shall be binding on Seller unless expressly agreed
     to in a writing signed by an officer of Seller.

11.6  Notices. All notices, payments, reports and other communications required
      -------
     or permitted hereunder shall be in writing and shall be mailed by first
     class, registered or certified mail, postage prepaid, or otherwise
     delivered by hand, by messenger (including express mail courier services)
     or by facsimile, addressed to the addresses first set forth above or at
     such other address furnished with a notice in manner set forth herein. Such
     notices shall be deemed to have been served when delivered or, if delivery
     is not accomplished by reason of some fault of the addressee, when
     tendered. Notices shall be addressed as follows:

If to Seller:  UMC Group (USA)  Copy to:  Law+
         488 DeGuigne Drive  993 Highlands Circle
         Sunnyvale, CA 94086  Los Altos, CA 94024
         Attn: President  Attn: Peter Courture, Esq.
                                    Fax (650) 968-8885

If to Buyer:  Centillium Communications Inc.
         47211 Lakeview Boulevard
         Fremont, CA 94538
         Attn: Vice President of Operations
<PAGE>

11.7  Assignment. Neither this Agreement nor any of the rights and obligations
      ----------
     created hereunder may be assigned, transferred, pledged, or otherwise
     encumbered or disposed of, in whole or in part, whether voluntarily or by
     operation of law or otherwise, by any party, without the prior written
     consent of the other party. This Agreement shall inure to the benefit of
     and be binding upon the parties' permitted successors and assigns.

11.8  Captions and Section Headings. The captions and section and paragraph
      -----------------------------
     headings used in this Agreement are inserted for convenience only and shall
     not affect the meaning or interpretation of this Agreement.

11.9  Partial Invalidity. If any paragraph, provision, or clause thereof in this
      ------------------
     Agreement shall be found or be held to be invalid or unenforceable in any
     jurisdiction in which this Agreement is being performed, the remainder of
     this Agreement shall be valid and enforceable and the parties shall
     negotiate, in good faith, a substitute, valid and enforceable provision
     that most nearly reflects the parties' intent in entering into this
     Agreement.

11.10  Presumptions. In construing the terms of this Agreement, no presumption
       ------------
     shall operate in either party's favor as a result of its counsel's role in
     drafting the terms or provisions hereof.

11.11  Language. The English language shall govern the meaning and
       --------
     interpretation of this Agreement.

11.12  Waiver. The failure of either party to enforce at any time the provisions
       ------
     of this Agreement, or the failure to require at any time performance by the
     other party of any of the provisions of this Agreement, shall in no way be
     construed to be a present or future waiver of such provisions, nor in any
     way affect the right of either party to enforce each and every such
     provision thereafter. The express waiver by either party of any provision,
     condition or requirement of this Agreement shall not constitute a waiver of
     any future obligation to comply with such provision, condition or
     requirement.

11.13  Cumulative Remedies. The remedies under this Agreement shall be
       -------------------
     cumulative and not alternative and the election of one remedy for a breach
     shall not preclude pursuit of other remedies unless as expressly provided
     in this Agreement.

11.14  Confidentiality of Agreement. Each party agrees that the terms and
       ----------------------------
     conditions of this Agreement and Quotations shall be treated as
     confidential information of both parties, and that neither party will
     disclose the terms or conditions to any third party without the prior
     written consent of the other party, provided, however, that each party may
     disclose the terms and conditions of this Agreement, to the extent
     necessary:

11.14.1  as required by any court or other governmental body;
<PAGE>

11.14.2  as otherwise required by law;

11.14.3  to legal counsel of the parties, accountants, and other professional
      advisors;

11.14.4  in confidence, to banks, investors and other financing sources and
      their advisors;

11.14.5  in connection with the enforcement of this Agreement or rights under
      this Agreement; or

11.14.6  in confidence, in connection with an actual or prospective merger or
      acquisition or similar transaction.

11.15  Authority. Each party represents that all corporate action necessary for
       ---------
     the authorization, execution and delivery of this Agreement by such party
     and the performance of its obligations hereunder has been taken.

11.16  Counterparts. This Agreement may be executed in two (2) or more
       ------------
     counterparts, all of which, taken together, shall be regarded as one and
     the same instrument.

     IN WITNESS WHEREOF, the parties have authorized their undersigned
representatives to sign this Agreement and to bind them to its terms and
conditions in accordance with the foregoing.

Buyer:    Seller:

/s/ William F. Mackenzie          /s/ Jim Kupec
------------------------          -------------
Authorized Signature  Authorized Signature

William F. Mackenzie              Jim Kupec
--------------------              ---------
Printed Name                    Printed Name

Vice President, Operations        President, Worldwide Marketing/Sales
--------------------------        ------------------------------------
Title                                                        Title

March 8, 2000                     March 7, 2000
-------------                     -------------
Date                                                         Date
<PAGE>

                                   EXHIBIT A
                                   ---------
                                   Quotation
                                   ---------


Exhibit A.01 - Initial Process (es)

UMC STANDARD "0.35 um CMOS double-layer poly and triple-layer metal (2P3M)
process on 8-inch non-epi wafers".

Exhibit A.02 - Price Quote

William F. Mackenzie  ref.:CC030200
Vice President of Operations  3/6/00(revised)
Centillium Communications

Process Technology
0.35 um CMOS double-layer poly and triple-layer metal (2P3M) process on 8-inch
non-epi wafers

Mask Tooling
A mask set for design using the above technology will be provided at a NRE
charge of $37,900. Mask charge per layer shall be as follows:
<TABLE>
<CAPTION>

Layer         Price
-----------  -------
<S>          <C>

Diffusion    $ 3,000
N-Well       $ 1,600
P-Well       $ 1,600
Poly 0       $ 3,000
HR           $ 1,600
Poly 1       $ 3,000
N+           $ 1,600
P+           $ 1,600
SAB          $ 1,600
Contact      $ 3,000
Metal 1      $ 3,000
Via 1        $ 3,000
Metal 2      $ 3,000
Via 2        $ 3,000
Metal 3      $ 3,000
Pad          $ 1,300

Total        $37,900
</TABLE>
<PAGE>

Proto Lot

A proto lot, processed with HOT LOT status, consists of a minimum of 6 wafers
and without process split conditions, will be provided at a NRE charge of
$25,000 per lot. UMC guarantees that wafers from this prototype lot meet our
outgoing PCM specifications.

Corner Lot

An engineering comer lot with a maximum of 14 wafers, processed with QTAP
status, will be provided at a NRE charge of $25,000 per tot. UMC guarantees that
nominal wafers from this lot meet our outgoing PCM specifications.

Wafer Price
Monthly run-rate   *  500 wafers: $1,400 per wafer
Monthly run-rate   ** 500 wafers: $1,380 per wafer


Notes:
1.   NRE charges for the proto and comer lots are applicable only for the first
     tape-out of a new technology.
2.   The Super Hot Lot charge is $5,000 per lot for the above mentioned process
     technology.
3.   Wafers shall meet UMC standard PCM data.

Exhibit A.03 - Fabrication Cycle Times

Prototype:    20 days Cycle Time from mask generation to wafer out.

              11 days from Metal 1 to wafer out.

Production:  38 days to wafer out after P.O. acceptance.

Exhibit A.04 - CAPACITY
               --------


<TABLE>
<CAPTION>
Product                           Current Capacity            Additional forecast        Upside Max Capacity
                                  Based on monthly            time needed before       incremental to Current
                                  submission of 12            wafer start to meet             Capacity
                                   month forecast                Upside Demand
                                   (wafers/month)                                          (wafers/month)
<S>                          <C>                          <C>                          <C>
Analog CPE                                          100   8 weeks                      100 WAFERS
Analog CO                                           100   8 weeks                      100 WAFERS
Analog Line Driver                                   50   8 weeks                      50 WAFERS
</TABLE>
------------
*  less than
** greater than or equal to
<PAGE>

                                   EXHIBIT B
                                   PROCEDURES

B.1  QUALIFICATION, HOT RUNS & PILOT RUNS
     ------------------------------------

B.1.1  All pilot runs and hot runs ("Hot Lots") require Seller's written
consent.

B.1.2  For engineering lots, split and hold conditions will be as set by written
agreement with Seller, and no splits or hold conditions will be permitted
without Seller's written consent.

B.1.3  The minimum quantity of wafers for each split condition is two (2)
wafers.

B.1.4  The minimum quantity for each pilot run is twelve (12) wafer starts.
Regardless of anything to the contrary, Seller's only obligation for pilot runs
is that six (6) out of twelve (12) wafer starts shall meet the PCM
specifications agreed upon in writing before wafer start.

B.2.  PRODUCTION RUNS & ON-HOLD WAFERS
      --------------------------------

B.2.1  Unless otherwise conspicuously stated in a purchase order accepted and
signed by Seller, the minimum quantity in any lot shall be 25 wafers and no
staged wafer runs will be allowed in production without Seller's consent.

B.2.2  Subject to the other terms and conditions herein, by conspicuous written
request in Buyer's purchase order, Buyer may request staging of mask code and
gate array wafers as follows:

     (a)  the purchase order must include the holding stage and forecast release
          date;

     (b)  the minimum quantity for any stage release shall be at least six (6)
          wafers;

     (c)  all stage releases which have less than eighteen (18) wafers shall be
          subject to surcharge in an amount Seller will quote;

     (d) if the holding time for any step is more than four weeks, for each two
week and for each partial two week period thereafter, Buyer will pay a per hold
wafer surcharge equal to three percent (3%) of the total purchase order price;

     (e) if any on-hold time exceeds eight weeks, Buyer will pay Seller the full
purchase order price plus the applicable surcharges stated above;
<PAGE>

     (f) if any on-hold time exceeds ten weeks, in addition to all other
remedies, Seller may scrap the staged wafers from the production line, unless
before the expiration of that on-hold time Seller receives written request from
Buyer to return the staged wafers.

B.2.3  Regardless of anything to the contrary, once the purchase order has been
received by Seller, Seller will not be obligated to accept or honor orders or
requests to hold wafers.

B.3 Wafer Cycle Time. Unless otherwise agreed in writing, Wafer Cycle Time--the
    ----------------
time from wafer start (and written approval of PCM specifications) to final
visual inspection at Seller's premises--shall be as stated in Seller's written
quotation for the specific Products.
<PAGE>

                                Reciprocal NDA

                      RECIPROCAL NON-DISCLOSURE AGREEMENT

     Effective Date:     8/11/98
                         -------

     To protect certain confidential information that may be disclosed between
them. United Microelectronics Corporation, a California Corporation with
principal offices at 790 Palomar Ave. Sunnyvale, California ("UMC") and
Centillium Technology (the "Company") agree:
---------------------

  1.  This Reciprocal Non-Disclosure Agreement ("Agreement") shall only apply to
information designated as "CONFIDENTIAL" at the time of disclosure as follows:

     (a) Confidential Information disclosed in any tangible form or thing must
be marked or labeled clearly as "CONFIDENTIAL" or with a similar legend
sufficient to notify the receiving party that it is subject to the terms of this
Agreement;

     (b) Confidential Information disclosed in any of the manner must be clearly
identified as "CONFIDENTIAL" at the time of disclosure, and summarized in
reasonable detail and designated as "CONFIDENTIAL" in a writing delivered to the
receiving party within thirty (30) days of oral disclosure.

  2. Each party agrees that for a period of five (5) years, and notwithstanding
any termination, expiration or cancellation hereunder, it will hold in strict
confidence and not disclose to any third party any Confidential Information
received from the other party hereto except as expressly agreed upon in writing.
Each party further agrees that it will not use or incorporate any Confidential
Information received from the other party hereto for any purpose whatsoever
except solely for the evaluation and/or pursuit of mutually amicable business
relations between the Company and UMC. Notwithstanding anything to the contrary,
to the extend reasonably appropriate in connection with the evaluation and/or
pursuit of mutually amicable business relations, UMC may disclose Confidential
Information from Company to one or more of the foundries within the UMC Group
subject to the requirement that the parties will be bound as if such foundry was
part to this Agreement. For purposes of this Agreement, the foundries in the UMC
Group include United Microelectronics Corporation's Fabs I and II, United
Semiconductor Corporation, United Integrated Circuits Corporation, United
Silicon, Inc. and the joint venture to be formed to operate the foundry location
currently known as UMC's Module 5 in the Science Based Industrial Park, Hsin-Chu
City, Taiwan.

  3. Each party shall secure and safeguard any and all things, documents, work
in process, and work product that embodies Confidential Information of the other
in locked files or areas reasonably restricting access and preventing
unauthorized use and/or disclosure. Each party further agrees that it will
maintain reasonable procedures to prevent accidental or other loss of any
Confidential Information of the other, and to use at least the same degree of
care for such information as it uses to protect its own proprietary information.
In the event of any loss, disclosure or use of Confidential Information in
violation of this Agreement, the party involved shall immediately notify the
other.

  4. The obligations of this Agreement shall not apply to Confidential
Information which the receiving party shows is:

     (a) already in the possession of the receiving party at or before the time
     of disclosure hereunder as reasonably shown by evidence existing at the
     time of disclosure; or

                                      23
                               UMC CONFIDENTIAL

                                       24
<PAGE>

     (b) now or hereafter publicly known through no wrongful act of the
     receiving party (provided that if Confidential Information becomes publicly
     known this shall not excuse a prior breach); or

     (c) LAWFULLY RECEIVED FROM a THIRD PARTY WITHOUT OBLIGATION OF CONFIDENCE;
     OR

     (d) independently developed by the receiving party; or by persons not
     having access to the Confidential Information; or

     (e) approved for release by written authorization of the disclosing party

     (f) disclosed pursuant to the requirement or demand of a lawful
     governmental or judicial authority, but only to the extent required by
     operation of law, regulation of court order.

  5.  Upon termination, cancellation or expiration of this Agreement, or upon
written request of the disclosing party, the receiving party shall promptly
return to the disclosing party all documents and other tangible things
reflecting Confidential Information of the disclosing party, together with all
copies, extract, summaries and (except as provided by agreement) other material
derived therefrom.

  6.  Confidential Information shall remain the property of the disclosing
party. The parties agree that nothing in this Agreement (expressly or impliedly)
grants any patent, copyright, trademark, mask work, trade secret or other
property right to the receiving party, by licensee or otherwise. The parties do
not intend that any agency, joint venture or partnership relationship be created
between them by this Agreement.

  7.  Neither party has an obligation under this Agreement to purchase nay item
or service from the other or to offer for sale products using or incorporating
Confidential Information. Either party may, at its sole discretion, and without
using Confidential Information of the other, offer products for sale, modify
products and/or discontinue products.

  8.  Notwithstanding anything to the contrary, all processes, recipes, and
manufacturing, fabrication, assembly and testing techniques, and improvements
relating thereto ("process technology") provided and/or developed by or on
behalf of UMC shall be wholly owned by and the property of UMC and UMC shall not
be limited or restricted by any terms of this Agreement with respect to any
process technology unless clearly stated to the contrary in a writing signed by
an officer of UMC and identifying the specific information involved in precise
detail.

  9.  This Agreement shall be governed by and construed under the laws of
California.

  10.  There are no understandings, agreements, or representations, expressed or
implied, regarding the Confidential Information except as stated above. This
agreement may not be amended, modified or altered except by a writing signed by
both parties hereto.


UMC  COMPANY

By: /s/ Jean Tien                    By: /s/ William F. Mackenzie
    -------------                        ------------------------

Name/Title: Jean Tien                Name/Title: William F. Mackenzie
           ----------                            --------------------

Customer Engineering Director      Vice President, Operations

                                      24
                               UMC CONFIDENTIAL

                                       25