Mentor Graphics adds user defined fault models and cell-aware ATPG to improve IC test quality

INTERNATIONAL TEST CONFERENCE, ANAHEIM, USA: Mentor Graphics Corp. has announced new capabilities in the Tessent TestKompress and the Tessent FastScan tools that enable higher defect coverage and lower defect per million (DPM) levels for quality-critical applications like military, medical, automotive, and many others. User defined fault models (UDFM) and a new cell-aware ATPG flow together allow customers to target subtle shorts and open defects internal to standard cells that are not adequately detected with the standard stuck-at or transition fault models.

“Cell-aware testing based on UDFM allows us to increase the quality of our manufacturing test by catching defects that would have gone undetected using conventional fault models,” said Jeff Rearick, senior fellow at AMD.

“Traditional fault models ensure that the periphery of standard cells and the interconnections between them are fully tested, but can miss some bridging or open defects internal to the cells. With the UDFM and cell-aware capabilities, TestKompress can generate patterns to specifically target these additional defects, giving us higher confidence in our production testing with minimal impact to test time. This takes us a big step closer to true zero defect quality control.”

Cell-aware fault models are generated using a one-time cell library characterization flow, which uses the Calibre extraction tools and the Mentor Eldo product for transistor level fault simulation. Once characterization has been performed, the cell internal fault models are automatically incorporated into TestKompress pattern generation using the new UDFM syntax.

Cell library characterization is also available as a service from Mentor Consulting. Additionally, customers can use the UDFM capability to define any proprietary fault model that may be needed to improve quality levels for their specific process or application.

“As we move to more advanced process nodes, we see a variety of new failure modes that must be addressed by IC testing,” said Steve Pateras, product marketing director at Mentor Graphics. “UDFM allows customers to adapt to these new faults without waiting for commercial fault model libraries to catch up. Mentor continues to push the envelope on automated IC testing with new technology to maintain the highest test quality while reducing test development effort and, more importantly, the production cost of testing.”