PDF Solutions, Inc. Acquires AISS, GmbH.

Business Editors/High-Tech Writers

SAN JOSE, Calif.--(BUSINESS WIRE)--June 5, 2000

The Acquisition Will Substantially Improve PDF's Capability

to Optimize IC Product Layout for Its Customers,

Greatly Increasing Yield and Performance

PDF Solutions, Inc., the leading independent provider of yield ramp and performance solutions to the IC industry, today announced completion of its acquisition of AISS, GmbH. AISS provides software (including SiCat-Core, OPTISSIMO, and PROXECCO) to model and compensate for the physical effects involved in IC mask making and lithography.

The integration of PDF's characterization vehicles and analysis software with AISS' mask and lithography technology will dramatically improve the company's ability to diagnose and correct yield inhibitors for deep-submicron manufacturing process technologies through both process and layout modifications.

"This merger brings a host of complementary technologies to PDF that help bridge the gap between design, layout, and manufacturing to accelerate yield ramp. Integrating AISS' layout pattern characterization capabilities with PDF's process characterization vehicles provides the most accurate model of layout and process interactions. With these models, we will be able to identify product-based yield loss by design block and process module to create a wider process window and more manufacturable designs. Working with our customers, we can now more quickly ramp yield, improve performance, and overcome the design process interaction issues that are becoming more prevalent as companies move further into the deep submicron world," said Dave Joseph, PDF's V.P. of Products and Methods.

AISS has developed advanced software solutions that seamlessly integrate with PDF's existing yield ramp products and services. Its SiCat-Core tool provides an engine for analyzing and verifying the manufacturability of ICs. Already tightly integrated with PDF's pdEx, this software provides the underlying capability to support pdEx's prediction of the yield impact of random and systematic yield loss mechanisms.

Developed in close collaboration with Infineon Technologies (NYSE:IFX), AISS' OPTISSIMO software provides the only field-proven model-based OPC solution. This software complements existing rule-based schemes with an additional verification step that identifies violations where the uncorrected error exceeds a specified tolerance. The model-based approach is then applied to those selected areas. Moreover, OPTISSIMO provides the capability to apply OPC to phase shift designs for 0.13 (micron)m technologies and below.

"We are pleased that AISS and PDF Solutions decided to join forces as we expect it to increase the market presence of AISS' excellent software IP, in particular, OPTISSIMO," said Wilhelm Maurer, Sen. Project Manager at Infineon. We look forward to continuing our collaboration with PDF's AISS Division.

AISS' PROXECCO provides market-leading capability to correct proximity effects for E-beam lithography. Along with related technologies, this tool helps PDF further bridge the gap between design and manufacturing by ensuring the integrity of photomasks used in production. Using PDF technology, critical E-beam corrections and reticle quality metrics are validated statistically through electrical measurements at the wafer level. PROXECCO is currently sold to all major mask makers in conjunction with Numerical Technologies (Nasdaq:NMTC) CATS software.

"To get the best results from layout characterization and optimization software, you need to take into account process characteristics. Now, we can provide customers with the most physically accurate solution by complementing our own layout expertise with PDF's process characterization and optimization solutions," said Thomas Waas, AISS co-founder. "Moreover, as our technical capabilities have been proven through extensive testing with select world-class manufacturers, we are very pleased to have global access to all top-tier manufacturers though PDF."

Under terms of the agreement, AISS will become a wholly owned subsidiary of PDF Solutions, Inc., operating under the name of PDF GmbH, AISS Division. PDF GmbH, AISS Division will continue all collaborations with existing AISS customers.

About AISS, GmbH

Based in Munich, Germany, AISS was founded with the mission to combine the world of physical modeling with advanced semiconductor layout. Building on that concept, AISS has achieved a world-class expertise in hierarchical data processing and high-speed, accurate modeling of physical effects. Working in close collaboration with customers and partners worldwide, AISS has demonstrated its capability to solve some of today's most challenging lithography problems, both in production and in R&D. Among its flagship products, PROXECCO provides the most accurate method for e-beam proximity correction combined with the highest throughput. OPTISSIMO is the optical proximity correction tool (OPC) with the highest precision available today, and AISS' tailored algorithms for layout analysis and extraction are unrivaled.

About PDF Solutions, Inc.

PDF Solutions, Inc. provides the IC industry's leading yield and performance improvement systems and software. PDF's results-driven approach combines manufacturability simulation and analysis software, supported by proven yield enhancement methodologies to increase product yield, performance, and profitability. By helping companies integrate the most advanced products and processes into their manufacturing facilities, PDF dramatically shortens the time to ramped production, giving clients the ability to capture maximum value from their products.

Established in 1991 as a spin-off from Carnegie Mellon's SEMATECH Center for Rapid Yield Learning, PDF is headquartered in San Jose, California. Major investors are U.S. Venture Partners and Telos Venture Partners, whose limited partners include Cadence Design Systems, Inc. (NYSE:CDN). Among current PDF clients are several of the top ten largest semiconductor companies in the U.S., Asia, and Europe.