Rise Time and Charge Collection Efficiency of Graphene-Optimized 4H-SiC PIN Detector

TL;DR

This paper reports on a graphene-optimized 4H-SiC PIN detector with improved rise time, high charge collection efficiency, and radiation resistance, expanding its potential applications in various detection fields.

Contribution

The study introduces a graphene-optimized 4H-SiC detector that reduces rise time and enhances charge collection efficiency while demonstrating radiation resistance, broadening application prospects.

Findings

Rise time reduced by 24% at 200 V

Charge collection efficiency of 99.22%

Radiation dose has minimal impact on performance

Abstract

Silicon carbide detectors exhibit good detection performance and are being considered for detection applications. However, the presence of surface electrode of detector limits the application of low-penetration particle detectors, photodetectors and heavy-ion detection. A graphene-optimized 4H-SiC detector has been fabricated to expand the application of SiC detectors.Its electrical properties and the charge collection performance of {\alpha} particles are reported. The effective doping concentration of lightly doped 4H-SiC epitaxial layer is about 4.5\times10^{13}cm^{-3}, approaching the limit of the lowest doping level by the SiC epitaxial growth technique. The rise time of the graphene-optimized ring electrode detector is reduced by 24% at 200 V, compared to ring electrode detector. The charge collection efficiency (CCE) of graphene-optimized 4H-SiC PIN is 99.22%. When the irradiation dose is 2\times10^{11} n_{eq}/cm^2, the irradiation has no significant impact on the rise time and uniformity of the rise time for the graphene-optimized 4H-SiC detectors. This study proves that graphene has a certain radiation resistance. Graphene-optimized 4H-SiC detectors can not only reduce the signal rise time, but also improve uniformity of signal rise time and stability of charge collection. This research will expand the application of graphene-based 4H-SiC detectors in fields such as low energy ions, X-ray, UV light detection, particle physics, medical dosimetry and heavy-ion detection.