4H-SiC PIN detector for alpha particles from room temperature to 90 °C

TL;DR

The paper addresses the need for radiation detectors that function reliably in high-temperature, high-radiation environments where cooling is costly. It presents the SICAR 4H-SiC PIN detector with a fully epitaxial structure, field-plate and ring-electrode design, and optimized ohmic contacts via TLM analysis, evaluated from room temperature up to 90 C using alpha spectroscopy. Key results show leakage currents below 10 nA at 300 V across the temperature range, a depletion capacitance around 4.5 pF with ~30 um depletion width, and a rise time near 333 ps at 90 C, with charge collection stable within ±10%. The findings demonstrate the practicality of 4H-SiC PIN detectors for extreme-environment radiation detection, potentially reducing cooling requirements for reactor monitoring, space applications, and high-energy experiments.

Abstract

In the field of high-energy particle detection, detectors operating in high-radiation environments primarily face high costs associated with power consumption and cooling systems. Therefore, the development of particle detectors capable of stable operation at room temperature or even elevated temperatures is of great significance. Silicon carbide (SiC) exhibits significant potential for particle detector applications due to its exceptional carrier mobility, radiation hardness, and thermal stability. Over the past decade, significant breakthroughs in silicon carbide epitaxial growth technology and device processing techniques have enabled the development of SiC-based particle detectors, providing a new technological pathway for particle detection in high-temperature environments. In this work, we fabricate a 4H-SiC PIN detector, named SIlicon CARbide (SICAR) and characterize its leakage current, capacitance, and charge collection across varying temperatures. The results indicate that the detector maintains a very low leakage current (< 10 nA) at 90 C, with no degradation in depletion capacitance or charge collection performance. Additionally, it achieves a fast rise time of 333 ps at 90 C, confirming its potential for high-temperature radiation detection applications.

Figures (7)

• Figure 1: SICAR v1.3 PIN (a) image and (b) epitaxial structure
• Figure 2: using TLM method get contact resistivity at 850 ℃ 5 min annealing conditions
• Figure 3: (a) leakage current and (b) capacitance with different temperature
• Figure 4: $\alpha$ source CCE setup
• Figure 5: 23 ℃, 300 V, $\alpha$ source test signal (a) waveform and (b) charge collection