Measurement of the electron–hole pair creation energy in a 4H-SiC p-n diode

Abstract

For 4H silicon carbide (4H-SiC), the values for the electron–hole pair creation energy ϵ i published in the literature vary significantly. This work presents an experimental determination of ϵ i using 50 μ m 4H-SiC p-n diodes designed for particle detection in high-energy physics. The detector response was measured for α particles between 4 . 2 MeV and 5 . 6 MeV for 4H-SiC and a silicon reference device. Different α energies were obtained by using multiple nuclides and varying the effective air gap between the α source and the detector. The energy deposited in the detectors was determined using a Monte Carlo simulation, taking into account the device cross-sections. A linear fit of the detector response to the deposited energy yields ϵ i = ( 7 . 83 ± 0 . 02 ) eV , which agrees well with the most recent literature. For the 4H-SiC detectors, a linewidth of 28 keV FWHM was achieved, corresponding to an energy resolution of 0.5 %.