Proton radiation damage tolerance of wide dynamic range SOI pixel detectors

TL;DR

This study evaluates the radiation tolerance of the INTPIX SOI pixel detector for space applications, demonstrating its resilience to proton radiation with minimal performance degradation after typical satellite doses.

Contribution

It provides the first assessment of proton radiation damage tolerance for the INTPIX SOI pixel detector in space-relevant conditions.

Findings

Energy resolution degrades less than 10% after 500 rad irradiation.

Gain and noise uniformity remain within 0.1% after irradiation.

INTPIX shows promising radiation tolerance for space X-ray detection.

Abstract

We have been developing the SOI pixel detector ``INTPIX'' for space use and general purpose applications such as the residual stress measurement of a rail and high energy physics experiments. INTPIX is a monolithic pixel detector composed of a high-resistivity Si sensor, a SiO2 insulator, and CMOS pixel circuits utilizing Silicon-On-Insulator (SOI) technology. We have considered the possibility of using INTPIX to observe X-ray polarization in space. When the semiconductor detector is used in space, it is subject to radiation damage resulting from high-energy protons. Therefore, it is necessary to investigate whether INTPIX has high radiation tolerance for use in space. The INTPIX8 was irradiated with 6 MeV protons up to a total dose of 2 krad at HIMAC, National Institute of Quantum Science in Japan, and evaluated the degradation of the performance, such as energy resolution and non-uniformity of gain and readout noise between pixels. After 500 rad irradiation, which is the typical lifetime of an X-ray astronomy satellite, the degradation of energy resolution at 14.4 keV is less than 10%, and the non-uniformity of readout noise and gain between pixels is constant within 0.1%.