STATS Expands Unique Thermal Simulation Service; Simplified Package Modeling Now Available Worldwide.

Business Editors/High-Tech Writers

SINGAPORE & MILPITAS, Calif.--(BUSINESS WIRE)--June 25, 2001

Continuing its commitment to provide innovative solutions to customers worldwide, ST Assembly Test Services Ltd ("STATS")(Nasdaq:STTS)(SGX:ST Assembly) has expanded its Simplified Package Modeling (SPM) services to customers in Europe and Asia.

SPM offers a unique approach to how thermal simulation is performed in the industry today. Traditional thermal simulation methods analyze semiconductor devices based on final package design drawings and finite analysis calculations. Rather than waiting for the completion of the final substrate or leadframe design, SPM can occur as soon as a customer identifies the basic package design requirements such as package type, die size, number of solder balls, and copper layers.

As demand for complex, non-symmetrical, stacked die, and other multi-chip packages continues to grow, conventional simulation techniques are limited to a small symmetrical section of the package as opposed to the package being modeled in its entirety with SPM. SPM also takes thermal simulation one step further by analyzing not only the package itself, but also elements such as the underlying printed circuit board and heat sinks. This translates into a distinct advantage for customers who have very large and/or complex package designs.

"The SPM methodology delivers unparalleled advantages to our customers through cycle time reduction, increased design flexibility, and a focus on complex design issues," said Dr. Roger Emigh, Manager of Package Characterization. "Building on the success of SPM with customers in the US, STATS is now extending its unique service offering to customers in Europe and Asia."

SPM provides customers a new level of flexibility and capability through the combination of STATS' package design expertise, its extensive thermal test database, and Flomerics FLOTHERM simulation tool. Customers receive SPM information at multiple points in the design process, which provides an opportunity to make necessary changes before final package design and reduces subsequent design changes or delays. As a result, design cycle time can be dramatically decreased.

Since introducing the SPM approach last year in the US, STATS' North American customers have enjoyed measurable benefits. In addition to the ability to access accurate thermal resistance data without waiting for final design drawings, customers also receive unmatched design flexibility, design cycle time reduction, and full package simulation irrespective of complexity and package symmetry.

About ST Assembly Test Services Ltd. (STATS)

ST Assembly Test Services ("STATS")(Nasdaq NM:STTS)(SGX:ST Assembly), is a leading semiconductor test and assembly service provider to fabless companies, integrated device manufacturers and wafer foundries. With its principal operations in Singapore and global operations in the United States, United Kingdom, Japan and Taiwan, STATS offers full back-end turnkey solutions to customers worldwide. STATS' expertise is in testing mixed-signal semiconductors, which are extensively used in fast growing communications applications such as data networking, broadband and mobile communications. STATS also offers advanced assembly services and has developed a wide array of traditional and advanced leadframe and laminate based products, including various ball grid array packages to serve some of the world's technological leaders. STATS was listed on the Nasdaq National Market and The Singapore Exchange in January 2000. Further information is available at www.stts.com.

Certain of the statements in this press release are forward-looking statements that involve a number of risks and uncertainties which could cause actual results to differ materially. Factors that could cause actual results to differ include : general business and economic conditions and the state of the semiconductor industry; demand for end-use applications products such as communications equipment and personal computers; decisions by customers to discontinue outsourcing of test and assembly services; changes in customer order patterns; rescheduling or cancellation of customer orders; changes in product mix; capacity utilization; level of competition; pricing pressures; continued success in technological innovation; delays in acquiring or installing new equipment; litigation and other risks described from time-to-time in the Company's SEC filings, including its annual report on Form 20-F dated March 30, 2001. The Company undertakes no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events, or otherwise.