Planar processed APDs and APD arrays for scintillation detection

In this paper, performance characteristics of new, planar processed silicon avalanche photodiodes (APD) and arrays are discussed for scintillation spectroscopy as well as direct X-ray detection. We have successfully fabricated large area APDs with sizes ranging from 1 cm/sup 2/ to 13 cm/sup 2/ using a novel planar process. The devices have shown very high gain (10/sup 4/), low noise (60% for /spl lambda/>400 nm). Direct X-ray detection has been achieved with high energy resolution (1.5 keV FWHM for 5.9 keV X-rays for 1 cm/sup 2/ size) at room temperature.