A wide spectral band photodetector with PtSi/p-Si Schottky-barrier

The photoresponse of a front-illuminated PtSi Schottky-barrier detector is measured in the wavelength range between 0.4 and 5.2m. In the wavelength range longer than 1.1m, the detection mechanism is the internal photoemission. On the other hand, the intrinsic mechanism becomes dominant in the wavelength range shorter than 1.1m. The measured data are in good agreement with values calculated from these two detection mechanisms. The photoresponse depends on the PtSi thickness in both wavelength ranges. For getting a high responsivity, it is important to make a thin uniform metal film. The visible and the thermal image with a PtSi Schottky-barrier wide spectral band imager are also demonstrated.