4H-SiC p-i-n Low-Energy X-Ray Detectors With P-Layer Formed by Al Implantation

The results of electrical characterization and X-ray detection measurement of 4H-SiC p-i-n diodes with the p-layer formed by Al implantation are reported. From the capacitance-voltage measurement, the effective doping concentration of the 4H-SiC epitaxial layer is determined to be $1.88\times 10^{14}$ cm ⁻³ . The detectors exhibited a consistently low leakage current of $\sim 6$ pA at −150 V, indicating excellent reverse blocking properties of the p-n junction formed by Al implantation. The measured full width at half maximum (FWHM) of the 59.5 keV gamma-ray peak is ~4.2 keV, corresponding to an energy resolution of 7%. In addition, the characteristic X-rays emitted from the V, Mn, Fe, Ni, Ge, Y, and Mo targets are detected by reducing the noise limit in the preamplifier. The linearity error between the peak channel and the featured $K\alpha $ line energy is within 0.02%. The detector demonstrates an FWHM of 1.76 ± 0.1 keV at 4.9 keV and 1.67 ± 0.05 keV at 17.5 keV. The obtained results show that the SiC p-i-n diodes with p-layer formed by Al implantation can be used as promising low-energy X-ray detectors with reasonable resolution.