Radiation-Induced Current Leakage Between Two n-MOSFET’s

Introduction

The Simulation Standard article “Simulating Radiation-Induced Shifts in MOSFET Threshold Voltage”1 gives a brief overview of the ways that ionizing radiation can affect semiconductor devices, and considers insulator charging in particular. In the Victory Device User’s Manual2 there is a more extensive discussion of radiation effects. Here we look at how insulator charging due to ionizing radiation can induce a leakage current between two MOSFET’s separated by a trench.

Simulation

To demonstrate how exposure to high-energy radiation can lead to a breakdown of the isolation between separate devices, we shall use Victory Device to simulate a pair of n-MOSFET’s, separated by a trench, that are bombarded by x-rays. The structure and doping of these MOSFET’s are shown in Figure 1.