Combined Effects of Transient Ionizing and Electromagnetic Pulse on Vertical NPN Bipolar Transistor

TL;DR

This study investigates how combined transient ionizing and electromagnetic pulses affect vertical NPN bipolar transistors, revealing nonlinear effects and mechanisms crucial for designing radiation-hardened circuits.

Contribution

It provides experimental and simulation insights into the combined effects of ionizing and electromagnetic pulses on transistors, highlighting nonlinear interactions and underlying physical mechanisms.

Findings

Combined effects exceed linear superposition in CEMP cases.

BEMP combined effects align with BEMP alone.

Mechanism analysis shows photocurrent variations under different pulses.

Abstract

Combined effects of transient ionizing and electromagnetic pulse on vertical NPN bipolar transistor were experimentally investigated under pulsed X-ray irradiation. Technology computer-aided design (TCAD) simulation method was also employed to explore the underlying physical mechanisms. The results demonstrate that the combined effect of a positive pulse injected into the collector (CEMP) and pulsed X-ray irradiation exceeds the linear superposition of their individual effects. Conversely, the combined effect of a positive pulse injected into the base (BEMP) and pulsed X-ray irradiation aligns closely with the results observed under BEMP acting alone. Mechanism analysis reveals that when CEMP and pulsed X-ray irradiation act simultaneously, there is a significant increase in both the drift photocurrent at the collector junction and the diffusion photocurrent near the collector junction. However, when BEMP and pulsed X-ray irradiation act simultaneously, these photocurrent components remain small, leading to a combined effect similar to the results observed when BEMP acts alone. These findings provide critical insights for the radiation-hardening design of bipolar circuits in harsh radiation environments.