Analysis of Trapping and Detrapping in Semi-Insulating GaAs Detectors

TL;DR

This paper investigates trapping and detrapping phenomena in semi-insulating GaAs detectors by analyzing alpha particle signals, determining trap activation energies, and identifying EL2+ as the dominant electron trap.

Contribution

It provides new insights into trap activation energies and the dominant electron trap in SI-GaAs through combined experimental and simulation analysis.

Findings

EL2+ is identified as the dominant electron trap.

Activation energies of two electron traps are determined.

Signal analysis reveals temperature and bias dependence of traps.

Abstract

To investigate the trapping and detrapping in SI-GaAs particle detectors we analyzed the signals caused by 5.48 MeV alpha particles with a charge sensitive preamplifier. From the bias and temperature dependence of these signals we determine the activation energies of two electron traps. Additional simulation and measurements of the lifetime as a function of resistivity have shown that the EL2+ is the dominant electron trap in semi-insulating GaAs.