Silvaco said it introduced the software to comply with customer requests for compatibility with TMA Technology Computer Aided Design (TCAD) software.

Silvaco originally said the demand was created by customers who told the company that Synopsys Inc. was planning to end-of-life the technology following its October 2004 acquisition of Swiss TCAD provider Integrated Systems Engineering (ISE).

However, Synopsys disputed this statement, causing Silvaco to retract it.

Synopsys issued a statement of its own Wednesday, in which Terry Ma, director of TCAD product marketing for the company's Silicon Engineering Group, said unequivocally that, "Synopsys does not have any plans to end-of-life its Stanford-based TMA software."

TCAD, pioneered at Stanford University under grants from the Defense Advanced Research Projects Agency (DARPA) in the 1970s and 1980s, was licensed to and commercialized exclusively by Technology Modeling Associates (TMA) and Silvaco starting in the late 1980s.

TMA was later acquired by Avanti Corp., which was then acquired by Synopsys in 2001.

In a statement issued by Silvaco Wednesday, Ivan Pesic, Silvaco CEO, said his company was asked by many companies to provide TMA TCAD compatibility.

A Silvaco spokesman said that the Silvaco and TMA versions of TCAD technology had diverged over the years, and, after seeing customer demand for the continuation of TMA TCAD, Silvaco spent the last six months making its products compatible.

"Silvaco has been aggressively improving the original Stanford software to meet all the needs of our worldwide customers who develop state-of-the-art technologies," Pesic said.

Silvaco (Santa Clara, Calif.) said it would continue to provide advanced TCAD technologies based on the latest physical models for process and device simulation. The company said it is now the only commercial supporter of the Stanford TCAD legacy.

The Silvaco spokesman said TCAD is used by, among other groups, designers who want to simulate the physics of the semiconductor industry's most advanced and upcoming technology nodes.