by Pawan Fangaria
We all know that Technology Computer Aided Design (TCAD) simulations are essential in developing processes for semiconductor manufacturing. From the very nature of these simulations (involving physical structure and corresponding electrical characteristics of a transistor or device), they are predominantly finite-element based simulations with complex set of equations to be solved which require large computation, thus increasing simulation time exponentially with the size of the device. It was okay for earlier generations of semiconductor technology nodes to rely on transistor or small cell level process and characterization to develop large designs which were then verified through several build-and-test cycles through actual foundries. However, for today’s nanometer technology nodes and large, complex, high-density designs with complex transistor structures like FinFET and others which exhibit excessive variability in manufacturing, it’s clear that the same old methodology will no longer be effective. . Along with the technology, the economics of chip manufacturing and marketing has become equally pressing, needing substantial reduction in P/Q ratio and very high TAT in order take advantage of ever shrinking windows of opportunity.