<PAGE>   1
                                                                   Exhibit 10.11


The omitted portions indicated by brackets have been separately filed with the
Securities and Exchange Commission pursuant to a request for confidential
treatment under Rule 406, promulgated under the Securities Act of 1933, as
amended.


             INTEL CORPORATION PURCHASE AGREEMENT - CHEMICALS/GASES


                                                   Agreement #:          C-06438
                                                   Effective Date: FEB. 18, 1999
                                                  Expiration Date:  DEC. 31,2001
                                                     CNDA #:               17452


BUYER:      Intel Corporation (and all Intel divisions and subsidiaries,
            hereinafter "BUYER" or "INTEL")
            Intel Corporation
            2200 Mission College Blvd
            Santa Clara, CA 95052-8119


SUPPLIER:   Cabot Corporation (hereinafter "SUPPLIER")
            500 Commons Drive
            Aurora, IL 60504


<TABLE>
<S>                                     <C>       <C>
                                        X         Terms and Conditions of Purchase Agreement - Goods
Addenda attached here to and            X    A    Product Description and Price Schedule
Incorporated herein by reference        X    B    Key Contacts & Intel Fab Locations
(Mark "X" where applicable.)            X    C    Quality Requirements
                                        X    D    Volume Commitments
                                             E
                                             F
</TABLE>

Buyer will purchase and Supplier will sell certain Items in accordance with the
Terms and Conditions and Addenda attached hereto. All Purchase Orders issued to
Supplier by Buyer during the term of this Agreement shall be governed only by
the Terms and Conditions of this Agreement notwithstanding any preprinted terms
and conditions on Supplier's acknowledgment or Buyer's Purchase Order. Any
additional or different terms in documents exchanged by the parties subsequent
to execution of this agreement are hereby deemed to be material alterations and
notice of objection to and rejection of them is hereby given.


INTEL CORPORATION                                 SUPPLIER

By: /s/  Mumtaz Ahmed                             By: /s/  Matthew Neville
    --------------------------                        --------------------------
Signature                                         Signature

Mumtaz Ahmed                                      Matthew Neville
Printed Name                                      Printed Name

Commodity Manager                                 GM & VP
Title                                             Title

2/18/99                                           2/18/99
Date                                              Date

<PAGE>   2

          TERMS AND CONDITIONS OF PURCHASE AGREEMENT - CHEMICALS/GASES

1.   DEFINITIONS

A.   "Release" means Buyer's authorization to ship in accordance with the
     Buyer's Purchase Order, and authorizing Supplier to ship a definite
     quantity of Items to a specified schedule. The Release is contained in the
     Purchase Order sent to Supplier.

B.   "Items" means the goods which Supplier is to provide to Buyer as set forth
     on Addendum A. Any Item which is custom made for Buyer shall be indicated
     by an asterisk (*) on such Addenda A.

C.   "Estimated Usage" or "Forecast" is the quantity Buyer reasonably expects to
     Release, however, Buyer shall not be obligated to Release such quantities
     of Items.

D.   "Purchase Order" is Buyer's document setting forth specific line Items
     ordered and Release information.

E.   "CIF" means "Cost, Insurance and Freight (named port of shipment)."
     Reference Incoterms 1990.

F.   "DDP" means "Delivered Duty Paid (named place of destination)." Reference
     Incoterms 1990.

G.   "DDU" means "Delivered Duty Unpaid (named place of destination)." Reference
     Incoterms 1990.

H.   "FMO" is Fab Materials Operation (a department within Intel Corporation).

I.   "FOB" means "Freight on Board (named port of shipment)." Reference
     Incoterms 1990.

J.   "FCA" means "Free Carrier (named place of destination)". Reference
     Incoterms 1990.

2.   TERM OF AGREEMENT

A.   The term of this Agreement shall begin on the Effective Date and continue
     to the Expiration Date, unless renewed pursuant to the terms of this
     Section. After the initial term, this Agreement shall be automatically
     renewed from year to year (for one-year periods) without action by either
     party, unless terminated pursuant to Section 5 of this Agreement. At
     Buyer's option, Items may be scheduled for delivery up to three (3) months
     following expiration or termination of this Agreement.

B.   This Agreement shall be effective to all Intel manufacturing facilities in
     the U.S. and the non-U.S. facilities identified in Addenda hereto.

3.   PRICING

A.   Prices of Items are as set forth in Addendum A, and may only be modified by
     mutual agreement. Supplier will publish newly negotiated prices to
     corporate representative and all Site buyers within 10 days of signed
     agreement.

B.   For any Item of which Supplier supplied Buyer with [ ]% or more of Buyer's
     requirements, as described in Addendum D, during the previous calendar
     year, Supplier agrees that the price for such Item shall always be
     Supplier's lowest net price charged any customer for like volumes of such
     Item. If the net price charged to Buyer for such is greater than that
     charged to another customer of Supplier for like volumes, Supplier shall
     adjust its price to Buyer to the lower price for as long as Supplier
     continues to offer such lower price to another customer. In addition, to
     the extent Buyer was charged a higher price during a period that Supplier
     was selling like volumes of such Item to another customer at a lower price,
     Supplier shall refund to Buyer the difference in the purchase price paid by
     Buyer and such lower price.

C.   In the event Supplier offers any Item of which Supplier supplied Buyer with
     [ ]% or more of Buyer's requirements as described in Addendum D during the
     previous calendar year at a lower price (taking into account volume
     discounts) either as a general price drop or only to some customer(s) for
     any reason, Supplier shall immediately inform Buyer of this price.


                                      -2-
<PAGE>   3

D.   Applicable taxes and other charges such as duties, customs, tariffs,
     imposts and government imposed surcharges, and freight shall be stated
     separately on Supplier's invoice.

E.   Additional costs, except those described in Section 3(D) or in Addenda A or
     D, will not be reimbursed without Buyer's prior written approval.

F.   Buyer reserves the right to have Supplier's records inspected and audited
     only by an independent third party auditor to ensure compliance with
     section 3B of this Agreement. At Buyer's option or upon Supplier's written
     demand, such audit will be performed by an independent third party at
     Buyer's expense. However, if Supplier is found to not be complying with
     section 3B of this Agreement in any way, Supplier shall reimburse Buyer for
     all costs associated with the audit. The results of such audit shall be
     kept confidential by the auditor, and only Supplier's failures to abide by
     the obligations of this Agreement shall be reported to Buyer.

G.   If a new product not included in Addendum A is to be purchased regularly,
     its price will be negotiated by a corporate representative at the time of
     initial purchase. If the product is for test purposes only at a given site,
     its price may be established between Supplier and a Sitebuyer. Said price
     shall be in effect until such time as an Intel part number is created, at
     which time a corporate-wide price will be negotiated by a corporate
     representative.

H.   Supplier will publish quarterly updates of Addendum A to FMO, all Buyer's
     Site Chemicals buyers and Buyer's Accounts Payable department, including
     new chemicals, their negotiated prices, supplier part numbers, Intel part
     numbers and any other changes. Quarterly updates of Addendum A will be
     issued on 1/30, 4/30, 7/30 and 10/30 of each year. Names and addresses of
     all parties to receive the updates will be provided and updated by Site
     buyer (see Addendum B).

I.   U.S. and non-U.S. prices will be fixed in U.S. dollars regardless of the
     Item country of origin or destination. Buyer retains the right to buy from
     Supplier or any subsidiaries of Supplier in U.S. dollars.

J.   The cost of containers, both returnable and disposable, diptubes and any
     required accessories will be included in the cost of the chemical

K.   Warehousing costs will be separate from this Agreement and will be billed
     separately.

4.   INVOICING AND PAYMENT

A.   Any applicable prompt payment discounts will be computed from the latest
     of: (i) the scheduled delivery date; (ii) the date of actual delivery; or
     (iii) the date a properly filled out original invoice or packing list is
     received. Payment is made when Buyer's check is mailed or EDI funds
     transfer initiated. Buyer shall make payment within forty-five (45) days of
     receipt of the proper original invoice or packing list.

B.   Original invoices or packing lists shall be submitted and shall include:
     full legal company name, payment terms, freight terms, tax status and rate,
     purchase agreement number from the Purchase Order, purchase order number,
     line Item number, Release number, part number, complete bill to address,
     description of Items, quantities, unit price and extended totals. Buyer's
     payment shall not constitute acceptance. Invoice must match Buyer's PO and
     packing slip exactly including unit of measure.

C.   Supplier shall provide to Buyer's Accounts Payable, and update as
     necessary, the names and phone numbers of a contact in Accounts Receivable.

D.   All international shipments must be accompanied by original invoice.

E.   Supplier will invoice Buyer for material and services no later than 120
     days after delivery.

5.   TERMINATION

     This Agreement may not be terminated by either party prior to the
     Expiration Date, except upon material breach by the other party. The
     Agreement may be terminated by


                                      -3-
<PAGE>   4

     either party on or after the Expiration Date by delivering to the other
     party written notice of termination at least one year prior to the date of
     such termination.

6.   CONTINGENCIES

     Neither party shall be responsible for its failure to perform due to causes
     beyond its reasonable control such as acts of God, fire, theft, war, riot,
     embargoes or acts of civil or military authorities. If delivery is to be
     delayed by such contingencies, Supplier shall immediately notify Buyer in
     writing and Buyer may either: (i) extend time of performance; or (ii)
     terminate all or part of the uncompleted portion of the Purchase Order at
     no cost to Buyer.

7.   DELIVERY, RELEASES AND SCHEDULING

A.   Any Forecasts provided by Buyer are for planning purposes only and do not
     constitute a Release or other commitment by Buyer.

B.   [Left intentionally blank]

C.   Supplier shall notify Buyer in writing within two (2) business days of
     receipt of Buyer's Purchase Order if Supplier is unable to make any
     scheduled delivery and state the reasons therefor. The absence of such
     notice constitutes acceptance of the Purchase Order and commitment to the
     Release terms.

D.   Supplier shall not deliver Items earlier than five (5) business days prior
     to agreed scheduled delivery dates and Buyer may return early, excess, or
     non-conforming shipments at Supplier's risk and expense.

E.   Buyer may reschedule or cancel any Release in whole or in part prior to the
     Release date at no additional charge.

F.   Buyer may place any portion of a Release on hold by notice which shall take
     effect immediately upon receipt. Releases placed on hold will be
     rescheduled or canceled within a reasonable time.

G.   Supplier shall not deliver Items until such Items are specified in an
     issued Purchase Order which contains specific Release dates for specific
     Items.

H.   Purchase orders will specify the destination date at Buyer dock or
     designated warehouse.

I.   Supplier must notify FMO, Accounts Payable and all Site Chemical buyers
     immediately in writing of any changes, including changes in delivery
     schedules, part numbers, contact persons and the party to be invoiced.

J.   Supplier must provide FMO with a Certificate of Analysis (C of A) or sample
     for each lot to be shipped, as directed in the most current appropriate
     Intel Specification (Addendum C).

K.   Buyer may return any standard Item in same condition as received within [ ]
     days of receipt. Buyer will pay return freight and disposal costs, if
     necessary (Disposal costs paid only if the product conformed to all
     required specifications in place). Reimbursement for Items returned will be
     made by credit memo.

L.   Supplier shall ship all Items according to the delivery address provided on
     each Purchase Order submitted by Buyer.

M.   Supplier shall provide and update as necessary the name and phone number of
     one person which Buyer's representative may contact regarding scheduling
     and delivery. Additionally, Supplier will provide 24-hour hotline/contact
     number which Buyer may contact in case of emergency.

N.   Supplier agrees to maintain safety stock on specified Items as mutually
     agreed with Buyer's local sites. Supplier shall notify Buyer whenever
     safety stock falls below minimum levels and will provide a corrective
     action plan to replenish Items. In the event Buyer no longer intends to
     purchase a particular Item from Supplier for use at a particular site,
     Buyer shall so notify Supplier of such fact and Buyer shall purchase
     Buyer's minimum required safety stock of such Items at that site.


                                      -4-
<PAGE>   5

O.   Supplier shall maintain an on-hand supply of emergency packaging material
     sufficient to meet pre-agreed requirements with Buyer's Site Chemical
     buyer.

8.   ACCEPTANCE AND WARRANTY

A.   Buyer may with reasonable advance notification inspect and test all Items
     at reasonable times before, during and after manufacture. If any inspection
     or test is made on Supplier's premises, Supplier shall provide reasonable
     facilities and assistance for the safety and convenience of Buyer's
     inspectors in such manner as shall not unreasonably hinder or delay
     Supplier's performance. All Items shall be received subject to Buyer's
     inspection, testing, approval and acceptance at Buyer's premises
     notwithstanding any inspection or testing at Supplier's premises or any
     prior payment for such Items. Items rejected by Buyer as not conforming to
     this Agreement or Item specifications whether provided by Buyer or
     furnished with the Item may be returned to Supplier at Supplier's risk and
     expense and, at Buyer's request shall immediately be repaired or replaced.

B.   Supplier warrants that all Items furnished here under shall be new, of the
     grade and quality specified, conform to all agreed-to specifications, and
     will be free of liens and encumbrances (excluding claims of intellectual
     property infringement, which are the exclusive subject of Section 14).
     These warranties shall survive any delivery, inspection, acceptance,
     payment or resale of the Items. Original specifications and any subsequent
     modifications to those specifications shall be agreed upon by both Buyer
     and Supplier. SUPPLIER MAKES NO OTHER REPRESENTATION OR WARRANTY OF ANY
     KIND, EXPRESS OR IMPLIED, AS TO MERCHANTABILITY, FITNESS FOR A PARTICULAR
     PURPOSE OR ANY OTHER MATTER WITH RESPECT TO THE ITEMS, WHETHER USED ALONE
     OR IN COMBINATION WITH OTHER SUBSTANCES, EVEN IF THE PURPOSES OR USES OF
     SUCH PRODUCTS ARE KNOWN BY SUPPLIER.

C.   During the Items' specified shelf life, at Buyer's option, Supplier shall
     promptly repair, replace or refund the purchase price of all Items not
     conforming to the foregoing warranties, and shall also refund the cost of
     return shipping of such Items. Supplier will bear the risk of loss of such
     Items while in transit. Supplier's warranty liability for damages arising
     from each "Non-Conformance Event" shall [ ]. Furthermore, in no event shall
     Supplier's [ ]. As used herein, "Non-Conformance Event" shall mean the
     receipt by Buyer of a lot of Items which are not in conformity with the
     warranty given in Section 8B above. IN NO EVENT SHALL SELLER BE RESPONSIBLE
     OR LIABLE FOR ANY SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING IN
     WARRANTY UNDER THIS AGREEMENT OR THE TRANSACTIONS CONTEMPLATED HEREBY. The
     [ ]contained in this Section 8 is separate and independent from the [ ]
     contained in Section 14, and the amount of liability imposed under one of
     these Sections does not limit or restrict the amount of liability imposed
     under another Section. NOTHING IN THIS SECTION IS INTENDED TO PLACE A
     LIMITATION ON EITHER PARTY'S LIABILITY IN TORT FOR PERSONAL INJURY.

D.   Freight charges for returned non-conforming Items shall be paid by Supplier
     with the understanding that returns must be authorized in accordance with
     Supplier's return authorization procedures. Returns must be authorized by
     Supplier within 10 days of Buyer's request. Credit for returned Items will
     be issued within 30 days of notification by Buyer.

E.   Notwithstanding anything to the contrary contained in this Agreement,
     Supplier represents and warrants to Buyer that there will be no disruption
     in the supply of those goods and/or services which are under the direct
     control of the Supplier as a result of or due to the date change from and
     between December, 1999, and January, 2000, nor due to the year 2000 being a
     leap year. Supplier does not provide any such warranty for disruptions
     caused by those goods and/or services which are not under the Supplier's
     direct control. As used herein, "direct control" refers to goods and/or
     services which the Supplier actively manages by contract and/or owns.
     Furthermore, in no event shall


                                      -5-
<PAGE>   6

     Seller's total and aggregate liability under such warranty exceed $500,000
     over the term of this Agreement

9.   PRODUCT SPECIFICATIONS/IDENTIFICATION/ ERRATA

A.   Supplier shall not modify the specifications for Items without Buyer's
     written consent. Supplier shall notify FMO and all Site Chemical buyers
     immediately in writing of any change in Supplier's part number, in the
     manufacturing process, packaging or description for any Item sold to Buyer
     at least ninety (90) days in advance of any changes. Such notice shall also
     be included in the quarterly update mentioned in Section 3 (I).

B.   Supplier shall cooperate with Buyer to provide configuration control and
     traceability systems for Items supplied hereunder.

C.   Items must comply with Buyer's raw material specifications (Intel
     Specification 07-400).

D.   As long as Buyer is purchasing a particular Item, Supplier shall notify FMO
     and all Site Chemical buyers at least one year in advance of expected
     discontinuance of that Item. Exception: In the event of changes or
     discontinuation required by governmental order or requirement, Supplier
     shall notify Buyer in writing immediately. Notification of any change in
     product specification must follow Intel's " Materials Change Control
     Procedure." (Intel Specification 07-120).

E.   Where an existing agreed-to Intel Specification (Addendum C) is updated,
     the updated Specification must be agreed to by Buyer and Supplier before it
     will be in effect.

10.  CONTAINERS AND DIPTUBES

A.   All necessary chemical containers, packaging and diptubes will be provided
     by Supplier and included in the cost of the Item.

B.   All containers and diptubes shall be inspected by Supplier before each use
     and repaired or replaced as necessary.

C.   At all times, ownership and title of containers and diptubes will remain
     with the Supplier.

D.   Buyer will not be responsible for any additional charges for acquisition,
     termination or disposal of containers or diptubes.

E.   In the event that containers or diptubes become damaged through neglect or
     misuse by Buyer, Buyer will reimburse Supplier an amount agreed upon and
     pro-rated based upon useful life.

F.   All packaging including quartz, stainless steel, bottles, drums and ICBs,
     shall be equipped with tamper evident seals.

11   PACKING AND SHIPMENT

A.   Shipments to Israel: Delivery terms for Israel will be DDP Intel,
     Jerusalem. Supplier fulfills its obligation to deliver when Items are made
     available at Buyer's dock or designated warehouse. Supplier will bear all
     risks, liabilities and costs involved in bringing the Items thereto. Buyer
     will ship empty containers to the point of manufacture in a timely manner.

B.   Shipments to Ireland: Delivery terms for Ireland will be DDU Intel,
     Leixlip. Supplier fulfills its obligation to deliver when Items are made
     available at Buyer's dock or designated warehouse. Supplier will bear all
     risks, liabilities and costs involved in bringing the Items thereto,
     excluding duties, taxes and other official charges payable upon
     importation. Buyer will ship empty containers to the point of manufacture
     in a timely manner.

C.   For all other Intel Factories, both U.S. and non-U.S., Items shall be DDP
     Buyer's dock or as otherwise specified in the Release. Buyer will ship
     empty containers to the point of manufacture in a timely manner. All Items
     shall be prepared for shipment in a manner which: (i) follows good
     commercial practice; (ii) is acceptable to common carriers for shipment at
     the lowest rate; and (iii) is adequate to ensure safe arrival. Supplier
     shall mark all containers with necessary lifting, handling and shipping
     information, purchase order number, date of shipment and the names of the
     Buyer and Supplier. Buyer shall


                                      -6-
<PAGE>   7

     notify Supplier of the method of shipment and expected delivery date. If no
     instructions are given, Supplier shall select the most cost effective
     carrier, given the time constraints known to Supplier. Supplier shall ship
     only the quantity of Items specified in the Release. Buyer may return at
     Supplier's expense any Items in excess of the quantity stated in the
     Release.

D.   Supplier shall be responsible for all Supplier's activities through
     manufacture, storage, transport, and delivery of Items to Buyer. In the
     event that Buyer must deploy emergency, safety, or materials personnel in
     response to an emergency or non-compliance with Intel or regulatory
     procedure involving Items supplied hereunder, Buyer and Supplier will
     review the incident. If Buyer and Supplier agree that (i) such deployment
     was necessary, and (ii)Supplier's negligent act or failure to act was the
     proximate cause of such emergency or non-compliance, then Supplier agrees
     to reimburse Buyer for the out-of-pocket cost incurred by Buyer in
     deploying its personnel to respond to such incident. Supplier will not be
     responsible for costs incurred by such deployment due to Buyer's negligent
     act or failure to act. International shipments: Supplier will provide
     Buyer's representative with shipping documents as requested. Buyer's
     purchase orders will contain detailed shipping instructions. E. Shipment of
     all Items qualified for Buyer's Preship or Direct Ship Programs will be
     done in accordance with latest mutually accepted Intel Specification 07-402
     (Intel Chemical and Gas Quality Program.).

12.  OWNERSHIP AND BAILMENT RESPONSIBILITIES

A.   Any specifications, drawings, schematics, technical information, data,
     tools, dies, patterns, masks, gauges, test equipment, and other materials
     furnished or paid for by Buyer shall: (i) be kept confidential; (ii) remain
     Buyer's property; (iii) be used by Supplier exclusively for Buyer's orders;
     (iv) be clearly marked as Buyer's property and segregated when not in use;
     (v) be kept in good working condition at Supplier's expense; and (vi) be
     shipped to Buyer promptly on demand.

B.   Supplier shall insure Buyer's property and be liable for loss or damage
     while in Supplier's possession or control, ordinary wear and tear excepted.

13.  CONFIDENTIALITY AND PUBLICITY

A.   During the course of this Agreement, either party may have or may be
     provided access to the other's confidential information and materials.
     Provided such are marked in a manner reasonably intended to make the
     recipient aware, or the recipient is sent written notice within forty-eight
     (48) hours of disclosure, that the information or materials are
     "Confidential", each party agrees to maintain such information in
     accordance with the terms of this Agreement and the CNDA referenced on the
     signature page of this Agreement or any applicable separate nondisclosure
     agreement between Buyer and Supplier. In the absence of a CNDA or other
     written agreement, at a minimum each party agrees to maintain such
     information in confidence and limit disclosure on a need to know basis, to
     take all reasonable precautions to prevent unauthorized disclosure, and to
     treat such information as it treats it's own information of a similar
     nature, until the information becomes publicly available through no fault
     of the non disclosing party. Supplier's employees who access Buyer's
     facilities may be required to sign a separate non-disclosure agreement
     prior to admittance to Buyer's facilities.

B.   The parties agree that neither will disclose the existence of this
     Agreement, nor any of its details or the existence of the relationship
     created by this Agreement, to any third party without the specific, written
     consent of the other. If disclosure of this Agreement or any of the terms
     hereof is required by applicable law, rule or regulation, or is compelled
     by a court or governmental agency, authority or body: (i) the parties shall
     use all legitimate and legal means available to minimize the disclosure to
     third parties of the content of the Agreement, including without limitation
     seeking a confidential


                                      -7-
<PAGE>   8

     treatment request or protective order; (ii) the disclosing party shall
     inform the other party at least ten (10) business days (i.e., not a
     Saturday, Sunday or a day on which banks are not open for business in the
     geographic area in which the non-disclosing party's principal office is
     located) in advance of the disclosure; and (iii) the disclosing party shall
     give the other party a reasonable opportunity to review and comment upon
     the disclosure, and any request for confidential treatment or a protective
     order pertaining thereto, prior to making such disclosure. The parties may
     disclose this Agreement in confidence to their respective legal counsel,
     accountants, bankers and financing sources as necessary in connection with
     obtaining services from such third parties. The obligations stated in this
     section shall survive the expiration or termination of this Agreement.

14.  PATENTS, COPYRIGHTS, TRADE SECRETS, TRADEMARKS AND MASKWORK RIGHTS

A.   Supplier makes no agreement to defend, indemnify or hold Buyer harmless
     from any costs, expenses, losses, damages or liabilities incurred because
     of actual or alleged infringement of any patent, trade secret or other
     intellectual property right by, or arising from use of, [ ] slurry or any
     other Items designated as custom by the parties. For all other Items,
     Supplier agrees to indemnify and hold Buyer harmless from any costs and
     expenses (including reasonable attorneys' fees) incurred in connection
     with, and damages awarded to a third party as a direct result of,
     adjudicated claims of infringement of any third party patent, trade secret,
     trademark or other intellectual property right arising out of the purchase
     of Items by Buyer or the use of Items by Buyer or Buyer's customers,
     provided, however, that Seller is not obligated to so indemnify Buyer, if
     (i) the sale of such Item by Supplier does not constitute contributory
     infringement or inducement to infringe; or (ii) Buyer modifies the Item; or
     (iii) Buyer uses the Item in a manner other than the specific use for which
     the Item is sold by Supplier. Buyer shall promptly notify Supplier of such
     claim or demand and shall permit Supplier to participate in the defense
     thereof.

B.   To the extent any settlement of a claim or demand is for an amount less
     than the [ ] set forth in this Section, Supplier shall have the right to
     settle said claim at its discretion.

C.   If an injunction issues as a result of any such claim or action or if
     Supplier determines in good faith that it is unable or unwilling to supply
     an Item because the Item itself or the use of the Item may infringe a
     patent or may constitute a misappropriation of a trade secret, Supplier
     agrees at its expense and Buyer's option to either: (i) procure for Buyer
     and Buyer's customers the right to continue using Items; (ii) replace them
     with non-infringing Items; or (iii) modify them so they become
     non-infringing. Buyer's sole remedy for Supplier's failure to supply or to
     obtain the remedy elected shall be [ ], and upon [ ] Supplier shall not be
     deemed in breach of this Agreement.

D.   In no event shall [ ]. The [ ] contained in this Section 14 is separate and
     independent from the [ ] contained in Section 8, and the amount of
     liability imposed under one of these Sections does not limit or restrict
     the amount of liability imposed under another Section.

15.  HAZARDOUS MATERIALS

A.   If Items or any services provided hereunder include hazardous materials as
     defined by relevant local, state, and national law, Supplier represents and
     warrants that Supplier and its personnel providing services to Buyer
     understand the nature of and hazards associated with the design and/or
     service of Items including handling, transportation, and use of such
     hazardous materials, as applicable to Supplier. Prior to causing hazardous
     materials to be on Buyer's property, Supplier shall obtain written approval
     from Buyer's Site Environmental/Health/Safety organization. Supplier will
     indemnify Buyer from any


                                      -8-
<PAGE>   9

     environmental liability incurred by Buyer which results from the shipment
     and delivery of hazardous Items to Buyer, provided Buyer's negligence was
     not a proximate cause of such liability.

B.   Supplier will timely provide Buyer with material safety data sheets and any
     other documentation reasonably necessary to enable Buyer to comply with
     applicable laws and regulations.

C.   Supplier hereby certifies that Items supplied to Buyer do not contain and
     are not manufactured with any ozone depleting substances, as those terms
     are defined by law.

16.  CUSTOMS CLEARANCE

     Upon Buyer's request, Supplier will promptly provide Buyer with a statement
     of origin for all Items and with applicable customs documentation for Items
     wholly or partially manufactured outside of the country of import.

17.  COMPLIANCE WITH LAWS

A.   Supplier shall comply with all national, state, and local laws and
     regulations governing the manufacture, transportation, and/or sale of Items
     and/or the performance of services in the course of this Agreement. In the
     United States, these may include, but are not limited to, Department of
     Commerce, Environmental Protection Agency, and Department of Transportation
     regulations applicable to hazardous materials.

B.   Supplier represents and agrees that it is in compliance with Executive
     Order 11246 and implementing Equal Employment Opportunity regulations and
     the Immigration Act of 1987, unless exempted or inapplicable.

18.  MERGER, MODIFICATION, WAIVER, AND REMEDIES

A.   This Agreement contains the entire understanding between Buyer and Supplier
     with respect to the subject matter hereof and merges and supersedes all
     prior and contemporaneous agreements, dealings and negotiations. No
     modification, alteration or amendment shall be effective unless made in
     writing, dated and signed by duly authorized representatives of both
     parties.

B.   No waiver of any breach hereof shall be held to be a waiver of any other or
     subsequent breach.

C.   Except as otherwise expressly limited herein, the parties' rights and
     remedies herein are in addition to any other rights and remedies provided
     by law or in equity.

D.   If any provision of this Agreement is determined by a court of competent
     jurisdiction to be invalid, illegal or unenforceable, such determination
     shall not affect the validity of the remaining provisions unless Buyer
     determines in its discretion that the court's determination causes this
     Agreement to fail in any of its essential purposes.

19.  ASSIGNMENT

     Neither party may assign or factor any rights in nor delegate any
     obligations under this Agreement or any portion thereof without the written
     consent of the other. However, Supplier may assign its rights and
     obligations hereunder to its direct and indirect subsidiaries, without such
     consent. Buyer may cancel this Agreement for cause should Supplier attempt
     to make an unauthorized assignment of any right or obligation arising
     hereunder.

20.  APPLICABLE LAW

     This Agreement is to be construed and interpreted according to the laws of
     the State of Delaware, excluding its conflict of laws provisions. This
     Agreement is not subject to the United Nations Convention on Contracts for
     the International Sale of Goods, in accordance with Article 6 thereof.


                                      -9-
<PAGE>   10

21.  HEADINGS

     The headings provided in this Agreement are for convenience only and shall
     not be used in interpreting or construing this Agreement.

22.  SPECIFIC PERFORMANCE

     Notwithstanding anything else contained in this Agreement, the parties
     hereto agree that failure to perform certain obligations undertaken in
     connection with this Agreement would cause irreparable damage, and that
     monetary damages would not provide an adequate remedy in such event. The
     parties further agree that failure to deliver against accepted Purchase
     Orders, or to deliver confirmed supply or pricing, are such obligations.
     Accordingly, it is agreed that, in addition to any other remedy to which
     the non breaching party may be entitled, at law or in equity, the non
     breaching party shall be entitled to injunctive relief to prevent breaches
     of the provisions of this Agreement, and an order of specific performance
     to compel performance of such obligations in any action instituted in any
     court of the United States or any state thereof having subject matter
     jurisdiction.

23.  SURVIVAL

     The provisions of Sections: 1, 8, 13, 14, 15, 20 will survive any
     termination or expiration of this Agreement. In addition, any license
     granted pursuant to Section 25 which is exercised prior to the Expiration
     Date shall remain in force and effect for a period of three (3) years
     following the Expiration Date, and Section 25 shall survive for this
     three-year time period following the Expiration Date.

24.  VOLUME COMMITMENTS

A.   Buyer's and Supplier's volume obligations and sales commitments for [ ] are
     set forth in Addendum D for the years set forth therein.

B.   Notwithstanding the volume obligations described above and set forth in
     detail in Addendum D of this Agreement, in the event that (i) Buyer is made
     a party to litigation arising from a claim of intellectual property
     infringement for which Buyer is indemnified, pursuant to Section 14 above,
     and (ii) Buyer determines, in good faith, after a thorough review of the
     claim, underlying patent, requested relief, Buyer's defenses and other
     relevant facts, that Supplier's indemnification obligation (which Supplier
     has the unilateral right to [ ]) would not be adequate with respect to the
     potential liability to such person, [ ], unless Supplier agrees in writing
     to increase [ ] set forth in Section 14 to a level which exceeds Buyer's
     good faith estimate of the amount of the likely damages to be incurred in
     such lawsuit.

C.   Notwithstanding the volume obligations described above and set forth in
     detail in Addendum D of this Agreement, in the event Supplier does not
     supply a particular Item for the reasons stated in Section 14C above,
     Supplier shall be released from its contractual obligation to supply the
     affected Item to Buyer.

25.  LICENSE

A.   Supplier agrees to grant to Buyer and/or its designee a contingent,
     royalty-free, fully-paid, worldwide, non-exclusive, irrevocable license,
     under those intellectual property rights that are owned by Supplier, or
     licensed to Supplier (which Supplier has the right to sublicense), that are
     necessary to make, use and import, and in the


                                      -10-
<PAGE>   11

     case of any such designee, to sell to Buyer or offer for sale to Buyer,
     those specific Items that Supplier is not able to supply under this
     Agreement for one of the following reasons:

     (i) Supplier is [ ] selling or delivering such specific Item(s) to Buyer,
     or

     (ii) Supplier determines in good faith that it is [ ].

     The above described license is expressly limited to the right to make Items
     for Buyer's sole use, or in the case of a designee, to make, sell or offer
     for sale Items (not supplied for the reasons set forth above), in an amount
     not to exceed those set forth in Addendum D, for Buyer's sole use. In
     addition, the above described license shall not obligate Supplier to
     disclose any trade secrets to Buyer or its designee other than the
     formulation (i.e., the ingredients and proportions) of the Item which has
     not been supplied. Any disclosure of such Item's formulation to Buyer
     and/or its designee shall be subject to Buyer and/or its designee entering
     into appropriate obligations of confidentiality with respect to such
     formulation.

B.   In the event (i) Buyer is made a defendant in litigation by any person or
     entity other than [ ], arising from a claim of patent infringement for
     which Buyer is indemnified, pursuant to Section 14 above; and (ii) Supplier
     is willing to continue to supply the affected Items; and (iii) Supplier is
     unable to settle such litigation for an amount less than the [ ]; and (iv)
     Buyer determines, in good faith, after a thorough review of the claim,
     underlying patent, requested relief, Buyer's defenses and other relevant
     facts, that Supplier's indemnification obligation (which Supplier has the
     unilateral right [ ] with respect to the [ ] to such person, then Supplier
     shall be obligated to either:

          (i) Grant to Buyer and/or its designee a non-exclusive,
     royalty-bearing, irrevocable license, under those patent rights that are
     owned by Supplier, or licensed to Supplier (which Supplier has the right to
     sublicense), that are necessary to make, use and import, and in the case of
     any such designee, to make and sell to Buyer or offer for sale to Buyer,
     those specific Items (in an amount not to exceed that set forth in Addendum
     D) that are the subject of such litigation, provided, that Supplier
     receives a non-exclusive, royalty-bearing, perpetual, irrevocable license
     under the patent that is being asserted in the infringement litigation and
     any other such patents of such party that are necessary to make and use
     those specific Items. The [ ] in such case with respect to the
     cross-licenses granted shall be [ ] of the purchase price or fair market
     value (if produced by Buyer internally) of the Item that is [ ]; or

          (ii) Grant to Buyer and/or its designee a non-exclusive,
     royalty-bearing, irrevocable license, under those patents that are owned by
     Supplier, or licensed to Supplier (which Supplier has the right to
     sublicense), that are necessary to make, use and import, and in the case of
     any such designee, to make and sell to Buyer or offer for sale to Buyer,
     those specific Items that are the subject of such litigation. The [ ] in
     such case shall be [ ] of the purchase price or fair market value (if
     produced by Buyer internally) of the Item that is [ ]. The foregoing
     license grant is expressly limited to the right to make Items (in an amount
     not to exceed that set forth in Addendum D) for Buyer's sole use.

     In the event Buyer exercises its right to have a license granted to Buyer
     and/or its designee under this Section 25B, any such license grant shall
     not subsequently


                                      -11-
<PAGE>   12

     revert to a license grant under Section 25A, regardless of whether Supplier
     subsequently stops supplying the affected Item.


                                      -12-
<PAGE>   13

                                   ADDENDUM A

                     PRODUCT DESCRIPTION AND PRICE SCHEDULE

A. [   ]

TABLE A

     PRICES WHICH APPLY IF BUYER PURCHASES [ ]% SHARE OF BUYER'S TOTAL
REQUIREMENTS FOR CMP SLURRIES UTILIZED IN [ ] POLISHING ASSOCIATED WITH THE
FOLLOWING MANUFACTURING PROCESSES OF BUYER: [ ]


<TABLE>
<CAPTION>
   CABOT PART #        PKG         POINT OF           DESTINATION         PRICE PER GALLON
                                 MANUFACTURE
<S>                  <C>        <C>               <C>                     <C>
       [ ]             IBC      United States     United States (FOB            $[ ]
                                                   local Warehouse)

                                                     Ireland (DDU)              $[ ]

                                                     Israel (DDP)               $[ ]

       [ ]             IBC       Barry, Wales     United States (FOB            $[ ]
                                                   local Warehouse)

                                                     Ireland (DDU)              $[ ]

                                                     Israel (DDP)               $[ ]

       [ ]           IBC/DTA    United States     United States (FOB            $[ ]
                                                   local Warehouse)
</TABLE>


TABLE B

     PRICES WHICH APPLY IF BUYER PURCHASES [ ]% SHARE OF BUYER'S TOTAL
REQUIREMENTS FOR CMP SLURRIES UTILIZED IN [ ] POLISHING ASSOCIATED WITH THE
FOLLOWING MANUFACTURING PROCESSES OF BUYER: [ ]

<TABLE>
<CAPTION>
   CABOT PART #        PKG         POINT OF          DESTINATION          PRICE PER GALLON
                                 MANUFACTURE
<S>                  <C>        <C>               <C>                     <C>
       [ ]             IBC      United States     United States (FOB            $[ ]
                                                   local Warehouse)

                                                    Ireland (DDU)               $[ ]

                                                     Israel (DDP)               $[ ]

       [ ]             IBC       Barry, Wales     United States (FOB            $[ ]
                                                   local Warehouse)

                                                    Ireland (DDU)               $[ ]

                                                     Israel (DDP)               $[ ]

       [ ]           IBC/DTA    United States     United States (FOB            $[ ]
                                                   local Warehouse)
</TABLE>


                                      -13-
<PAGE>   14

TABLE C

     PRICES WHICH APPLY IF BUYER PURCHASES [ ]% SHARE OF BUYER'S TOTAL
REQUIREMENTS FOR CMP SLURRIES UTILIZED IN [ ] POLISHING ASSOCIATED WITH THE
FOLLOWING MANUFACTURING PROCESSES OF BUYER: [ ]

<TABLE>
<CAPTION>
   CABOT PART #        PKG         POINT OF          DESTINATION          PRICE PER GALLON
                                 MANUFACTURE
<S>                  <C>        <C>               <C>                     <C>

       [ ]             IBC      United States     United States (FOB            $[ ]
                                                   local Warehouse)

                                                    Ireland (DDU)               $[ ]

                                                     Israel (DDP)               $[ ]

       [ ]             IBC       Barry, Wales     United States (FOB            $[ ]
                                                   local Warehouse)

                                                    Ireland (DDU)               $[ ]

                                                     Israel (DDP)               $[ ]

       [ ]           IBC/DTA    United States     United States (FOB            $[ ]
                                                   local Warehouse)
</TABLE>

     Prices for purchases of requirements percentages between the requirements
     percentages shown in the above tables (i.e. quantities between [ ]%, [ ]%
     and [ ]%) shall be determined by a straight line extrapolation of the
     prices shown in the above tables.

     The price per gallon of [ ] shall be calculated based upon the percent
     share of Buyer's requirements for [ ] or its equivalent associated with
     Buyer's [ ] manufacturing processes which Buyer forecasts for the relevant
     calendar year. For example, if Buyer purchases [ ]% of its total
     requirements for [ ] or its equivalent associated with Buyer's [ ]
     manufacturing processes in the form of [ ] from Supplier in calendar year
     2000, the price will be determined using Table B. However, if Buyer
     purchases [ ]% of its total requirements for [ ] or its equivalent
     associated with Buyer's [ ] manufacturing processes in the form of [ ] from
     Supplier in calendar year 2000, the price will be determined using Table A.

B. [    ]

<TABLE>
<CAPTION>
CABOT PART #       PKG     POINT OF     DESTINATION    PRICE BASED ON CUMULATIVE VOLUMES OF [       ] PURCHASED
                         MANUFACTURE
<S>                <C>  <C>             <C>            <C>         <C>        <C>        <C>          <C>            <C>
                                            #            [ ]-[ ]   [ ]-[ ]    [ ]-[ ]    [ ]-[ ]      [ ]-[ ]        > [ ]*
[   ]              IBC  United States   United States     $[ ]      $[ ]       $[ ]        $[ ]         $[ ]          $[ ]
                                        (FOB local
                                         warehouse)
                        United States      Israel         $[ ]      $[ ]       $[ ]        $[ ]         $[ ]          $[ ]
                                           (DDP)
                        United States   Ireland (DDU)     $[ ]      $[ ]       $[ ]        $[ ]         $[ ]          $[ ]
</TABLE>

*    volumes in thousands of gallons

     The price per gallon of [ ] shall be calculated based upon the cumulative
     volume of gallons of [ ] purchased by Buyer from Supplier during the term
     of this Agreement. Adjustments to the price, based upon the cumulative
     gallons of [ ] purchased by


                                      -14-
<PAGE>   15

     Buyer from Supplier, shall take effect in the quarter following the quarter
     in which Buyer surpasses a volume threshold.

C. [    ]

<TABLE>
<CAPTION>
       CABOT PART #               PKG          POINT OF MANUFACTURE            DESTINATION #          PRICE PER GALLON
<S>                               <C>          <C>                        <C>                         <C>
           [ ] *                  IBC              United States          United Sates (FOB local           $[ ]
                                                                                 warehouse)

           [ ] *                  IBC              United States               Ireland (DDU)                $[ ]

           [ ] *                  IBC              Barry, Wales                Ireland (DDU)                $[ ]

           [ ] *                  IBC              Barry, Wales           United Sates (FOB local           $[ ]
                                                                                 warehouse)
</TABLE>

*    [   ]

D. [   ]

<TABLE>
<CAPTION>
       CABOT PART #              PKG           POINT OF MANUFACTURE            DESTINATION #          PRICE PER GALLON
<S>                              <C>           <C>                        <C>                         <C>
            [ ]                  IBC              United States           United Sates (FOB local           $[ ]
                                                                                warehouse)
</TABLE>


                                      -15-
<PAGE>   16

                                   ADDENDUM B

KEY CONTACTS & INTEL FAB LOCATIONS


<TABLE>
<CAPTION>
DEPARTMENT/TITLE                            NAME                  PHONE

<S>                                         <C>                   <C>
OHKA:
Account Representative                      Brad Staley           630-375-5508
Accounts Receivable                                               630-585-9471
24-Hour Emergency Contact                   Brad Staley           630-375-5508
Schedule/Delivery Contact                   Soni Pahia            916-939-9364
General                                     Bruce Zwicker         630-375-5540


INTEL:
FMO
Commercial                                  Mumtaz Ahmed          408-765-88
Technical                                   Ara Philipossian      408-765-6256
                                            Joe Schoenholtz       408-765-2435
Buyers
        Ireland                             Caitriona Delaney     011-353-1-606-8630
        New Mexico                          Tami Freeman          505-893-3538
           Fab 6                            Oscar Ochoa           602-554-8417
           Fab 12                           Oscar Ochoa           602-554-8417
        Israel
  Fab 8                                     Anna Provad           011-972-2-5896357
           Fab 18                           Yaron Ozer            011-972-7-666-6953
        Santa Clara
        D2                                  Karen Ma              408-765-6152
                                            Ethel Swindall        408-765-2392
      Oregon                                Heather Holcomb       503-642-8693
      Massachusetts
         F17                                Tony Quarta
Accounts Payable:
        AZ/CA                               Linda Medill          503-696-3237
        OR                                  Jessica Ailshie       503-696-3046
        NM                                  Debbie Martin         503-696-3302
</TABLE>


                                      -16-
<PAGE>   17

                                   ADDENDUM C
                              QUALITY REQUIREMENTS


                     LIST OF GOVERNING INTEL SPECIFICATIONS

<TABLE>
<CAPTION>
SPEC. NO.           REV.                   TITLE                                                 ISSUE DATE

<S>                 <C>       <C>                                                                <C>
07-116              0         MATERIALS CHANGE CONTROL POLICY                                     05/22/98


07-123              2         SUPPLIER CORRECTIVE ACTION POLICY                                   02/25/98

07-124              4         FMO/ATMO-DISCREPANT RAW MATERIAL DISPOSITION POLICY                 06/09/98

07-400              7         CHEMICALS SPECIFICATION SYSTEM                                      06/05/97

07-401              6         PROCEDURE FOR SHIPPING & RECEIVING OF CHEMICALS                     12/05/97

07-402              5         INTEL CHEMICAL QUALITY PROGRAM                                      06/26/98

07-403              2         SHIPPING OF TEMP-SENSITIVE CHEMICALS                                12/05/97

07-411              4         PROCUREMENT SPEC FOR CHEMICALS                                      11/25/98
</TABLE>


                                      -17-
<PAGE>   18

                                   ADDENDUM D
                               VOLUME OBLIGATIONS

A. [    ]

         During the years set forth below, Buyer shall be obligated to purchase
from Supplier a [ ] volume of [ ] which is equal to the product of (i) Buyer's
total requirements for [ ] utilized in [ ] polishing associated with Buyer's [ ]
manufacturing processes ("[ ] Slurry Requirements"), multiplied by (ii) the [ ]
Percentage (set forth in the table below). During the years specified below,
Supplier shall be obligated to supply to Buyer a volume of [ ] which is equal to
the product of (i) Buyer's forecasted volume of [ ] Slurry Requirements for the
upcoming calendar year (which forecast shall be provided to Supplier 90 days
prior to the commencement of each calendar year), multiplied by (ii) the [ ]
Percentage (set forth in the table below).


[   ] SLURRY VOLUME OBLIGATIONS

<TABLE>
<CAPTION>
    CALENDAR YEAR             BUYER'S [ ] PERCENTAGE                 SUPPLIER'S [ ] PERCENTAGE
    -------------             ----------------------                 -------------------------
<S>                           <C>                                    <C>
        1999                           [ ] %                                   [ ] %
        2000                           [ ] %                                   [ ] %
        2001                           [ ] %                                   [ ] %
</TABLE>

Ninety days prior to the commencement of each calendar year, Buyer shall commit
and obligate itself to purchase from Supplier a specific percentage of its [ ]
Slurry Requirements (which percentage shall be at least as large as the [ ]
Percentage) which it shall purchase from Supplier during the upcoming year. The
amount of [ ] which Buyer will purchase, above the [ ] Percentage, will be
determined according to whether Supplier meets requirements set by Buyer's
Supplier Score Card.

B. [   ]

     During the years set forth below, Buyer shall be obligated to purchase from
Supplier a [ ] volume of [ ] which is equal to the product of (i) Buyer's total
requirements for [ ] utilized in [ ] polishing applications associated with
Buyer's [ ] manufacturing processes ("[ ] Requirements"), multiplied by (ii) the
[ ] Percentage (set forth in the table below). During the years specified below,
Supplier shall be obligated to supply to Buyer a volume of [ ] which is equal to
the product of (i) Buyer's forecasted volume of [ ] Requirements for the
upcoming calendar year (which forecast shall be provided to Supplier 90 days
prior to the commencement of each calendar year), multiplied by (ii) the [ ]
Percentage (set forth in the table below). Notwithstanding the foregoing, during
the course of any


                                      -18-
<PAGE>   19

calendar year, Buyer may, by giving 4 months advance written notification to
Supplier, increase its forecasted [ ] requirements for the remainder of the year
(starting after the 4 month notice period), provided, however, such new
forecasted amount may not exceed a volume which is greater than the product of
the remaining volumes from the original forecasted amount, multiplied by [ ].


[     ] SLURRY VOLUME OBLIGATIONS

<TABLE>
<CAPTION>
    CALENDAR YEAR           BUYER'S [ ] PERCENTAGE               SUPPLIER'S [ ] PERCENTAGE
<S>                         <C>                                  <C>
        1999                         [ ] %                                 [ ] %
        2000                         [ ] %                                 [ ] %
        2001                         [ ] %                                 [ ] %
</TABLE>

90 days prior to the commencement of 2001, Buyer shall commit and obligate
itself to purchase from Supplier a specific percentage of its [ ] Requirements
(which percentage shall be at least as large as the [ ] Percentage) which it
shall purchase from Supplier during 2001. The amount of [ ] which Buyer will
purchase, above the [ ] Percentage, will be determined according to whether
Supplier meets requirements set by Buyer's Supplier Score Card.

C. [    ]

During the years set forth below, Buyer shall be obligated to purchase from
Supplier a [ ] volume of [ ] which is equal to the product of (i) Buyer's total
requirements for [ ] utilized in [ ] polishing applications associated with
Buyer's [ ] manufacturing processes ("[ ] Requirements"), multiplied by (ii) the
[ ] Percentage (set forth in the table below). For each month of this Agreement,
Supplier shall be obligated to supply to Buyer a volume of [ ] which is equal to
the product of (i) the volume of [ ] Buyer purchased from Supplier during the
preceding month, multiplied by (ii) the [ ] Percentage (set forth in the table
below).

[    ]  SLURRY VOLUME OBLIGATIONS

<TABLE>
<CAPTION>
    CALENDAR YEAR                  [ ] PERCENTAGE                                [ ] PERCENTAGE
<S>                                <C>                                           <C>
        1999                           [ ] %                                          [ ] %
        2000                           [ ] %                                          [ ] %
        2001                           [ ] %                                          [ ] %
</TABLE>

D. [    ]

     Neither Buyer nor Supplier have any volume obligations with respect to [ ]


                                      -19-
<PAGE>   20

With respect to all of the above describe Items, in the event Buyer does not
purchase a particular Item for use in its facilities in either [ ] for any [ ],
Supplier shall no longer be obligated to supply such Item to Buyer's facilities
in the relevant geographic region.


                                      -20-