VLSI: linking design and manufacturing

A set of computer-aided design (CAD) tools that predict the effects of various manufacturing steps along with the chip´s internal dimensions is described. Called the Process Engineer´s Workbench, the system predicts the chip´s characteristics, their statistical distribution, and the manufacturing yield likely from any one fabrication process. The tools are even sensitive to the small random variations that increase in significance as devices shrink in size. Workbench can be used to compare its programs´ predictions and those of other software tools with actual measurements of devices and processes. Some existing CAD tools are reviewed to highlight the Workbench´s advantages, and the features of the latter are examined. Written in C language for a Digital Equipment VAXstation, Workbench was designed to be portable and runs on several other popular workstations. It contains two basic libraries, namely, one of device models, the other of process step models.<>