Logo
ScienceStack
Table of Contents
Fetching ...
Sign In

Stability of Charge Collection Efficiency and Time Resolution in 4H-SiC PIN Diodes Under X-ray Irradiation

Jiaqi Zhou, Sen Zhao, Xiyuan Zhang, Suyu Xiao, Chenxi Fu, Congcong Wang, Yanpeng Li, Weimin Song, Xin Shi

Abstract

This study evaluates the radiation tolerance of a 4H-SiC PIN detector under X-ray irradiation up to \SI{2}{MGy} (Si) at \SI{160}{keV}. The detector features a fully epitaxial vertical PIN structure with mesa terminations and field plates. Comprehensive pre- and post-irradiation characterization includes I-V/C-V measurements, charge collection efficiency (CCE) and timing resolution tests using $β$-particles ($^{90}$Sr). After \SI{2}{MGy} irradiation, the reverse leakage current remains at an ultralow level of $\sim 10^{-11}$ \si{A/cm^2} at \SI{-300}{V} with negligible degradation. C-V characteristics are basically consistent, with full depletion at \SI{~130}{V}. CCE for $β$-particles decreases by less than 5\%. The detector maintains good timing resolution: \SI{21}{ps} before and \SI{31}{ps} after irradiation, with jitter increasing moderately. These results demonstrate stable performance under extreme X-ray exposure, highlighting the detector's potential for radiation-hard applications in high-energy physics, space missions, and nuclear reactor monitoring.

Stability of Charge Collection Efficiency and Time Resolution in 4H-SiC PIN Diodes Under X-ray Irradiation

Abstract

This study evaluates the radiation tolerance of a 4H-SiC PIN detector under X-ray irradiation up to \SI{2}{MGy} (Si) at \SI{160}{keV}. The detector features a fully epitaxial vertical PIN structure with mesa terminations and field plates. Comprehensive pre- and post-irradiation characterization includes I-V/C-V measurements, charge collection efficiency (CCE) and timing resolution tests using -particles (Sr). After \SI{2}{MGy} irradiation, the reverse leakage current remains at an ultralow level of \si{A/cm^2} at \SI{-300}{V} with negligible degradation. C-V characteristics are basically consistent, with full depletion at \SI{~130}{V}. CCE for -particles decreases by less than 5\%. The detector maintains good timing resolution: \SI{21}{ps} before and \SI{31}{ps} after irradiation, with jitter increasing moderately. These results demonstrate stable performance under extreme X-ray exposure, highlighting the detector's potential for radiation-hard applications in high-energy physics, space missions, and nuclear reactor monitoring.
Paper Structure (10 sections, 3 equations, 5 figures)

This paper contains 10 sections, 3 equations, 5 figures.

Table of Contents

  1. INTRODUCTION
  2. Device Configuration and Processing Technology
  3. Irradiation and Characterization Setup
  4. Results and Discussion
  5. Current-Voltage Characteristics
  6. Capacitance-Voltage Characteristics
  7. Charge Collection Efficiency
  8. Timing Resolution
  9. Discussion
  10. Conclusion

Figures (5)

  • Figure 1: (a) Schematic diagram of the 4H-SiC PIN detector. (b) Detailed cross-sectional structure.
  • Figure 2: (a) Reverse I-V characteristics of 4H-SiC PIN detectors before and after X-ray irradiation at different doses. (b) Reverse C-V characteristics of 4H-SiC PIN detectors before and after X-ray irradiation at different doses.
  • Figure 3: Charge collection performance of 4H-SiC PIN detectors: (a) Experimental setup; (b) Landau fit of the collected charge spectrum, with MPV indicating characteristic charge; (c) CCE versus reverse bias for different irradiation doses.
  • Figure 4: Timing performance of the unirradiated 4H-SiC PIN detector at 300V bias: (a) Experimental setup; (b) Signal waveforms; (c) Time difference distribution fitted with Gaussian.
  • Figure 5: (a) Jitter distribution extracted from noise analysis; (b) Timing resolution as a function of X‑ray irradiation dose.