Integrated Circuit Design for Radiation Environments

6 Device Modeling and Simulation Techniques

6.1 Introduction

While Chapter 5 provided guidance for radiation testing of devices and circuits, the focus of this chapter is to show how radiation affects devices, examine methods for modeling the effects of radiation on devices, and look at some ways to implement radiation models. The first section of this chapter provides an overview of device modeling. This includes discussion of analysis programs, circuit simulators, intrinsic models, and composite models. The second section provides examples of pre‐ and post‐radiation characteristic curves for the more common devices that a circuit designer is likely to encounter, with discussion of the reasons for changes to device operation. This is not meant to be an exhaustive “effects” section, but only to provide some guidance on likely model parameter changes needed to match post‐radiation characteristics. The final sections discuss implementing post radiation models and single‐event transients (SET) simulation.

Providing an accurate prediction of circuit response to radiation environments can substantially reduce the nonrecurring engineering (NRE) costs and timeline for circuit qualification. This is easiest to accomplish by taking careful measurements during device testing and developing accurate models. If designing for space applications, cosmic rays must be taken into account. Predicting single‐event effects (SEE) behavior can be much more difficult, but considering that ...