Curve Tracing Program for Virtual Instrumentation

Stephen Beebe's research is in the area of TCAD known as virtual instrumentation. To date his major accomplishment is a curve-tracing program which automatically guides PISCES and other device simulators through complex I-V traces. Since the curve tracer is a C program which externally controls a device simulator via its input and output, it is capable of working with any simulator in which lumped resistance elements can be placed on a contact. Stephen's work now focuses on integrating the tracing program into a more general virtual failure-analysis tool. This tool will provide a user interface to facilitate the creation, execution, and analysis of device-failure simulations.

The curve-tracing program is ideal for virtual failure-analysis experiments such as latchup, BVceo, and electrostatic discharge (ESD) breakdown, phenomena distinguished by sharp turns in the I-V curve which are numerically unstable in conventional device simulation. Using a dynamic load line to adapt the bias conditions, the curve tracer keeps the simulation stable throughout the I-V trace. Development of the failure-analysis tool will be driven by Stephen's continued research and modeling of ESD at Advanced Micro Devices. The completed tool will allow a user to define a stimulus (test) for a device, run a dc or transient simulation, and then extract parameters from the resulting I-V curve (e.g., the trigger and hold voltages of a latchup curve).