Over 98% Linearity 4H-SiC Ultraviolet Position Sensitive Detector

In this work, a 6.5 mm × 6.5 mm large-area pin-cushion 4H-SiC UV position-sensitive detector (PSD) has been designed and fabricated. The device exhibits a low dark current of 6 pA, a high responsivity of 0.115 A/W and a good linear response at 275 nm. By carefully optimizing ion implantation parameters both in the photosensitive area and the border resistor area, the interference of the device’s surface electrodes has been largely alleviated, thereby achieving a low position error of less than 59 μm and a superior linearity over 98%. The resulting PSD exhibits obvious independence of light spot size and light power during the position measurement. The dependence of the detector’s resolution and response speed on position is also preliminarily investigated.