Noise analysis of low noise, high count rate, PIN diode X-ray detectors

Abstract

In a noise analysis for a planned p-i-n diode X-ray detector array, we particularly included process dependent 1/f and 1/f/sup 2/ terms, and explored the effect of input transistor parameters and peaking time t/sub p/ on energy resolution /spl Delta/E. We find that, for t/sub p/<1 /spl mu/s and careful processing, both 1/f and 1/f/sup 2/ terms are negligible and the usual approaches for minimum noise (reduce capacitances and shorten gate lengths) remain valid. We present a concrete example to see just how good performance may be. Thus a 0.1 pF detector, at 300 K with 0.5 /spl mu/m gate length transistors, produces a /spl Delta/E of 52 eV for a t/sub p/ of 180 ns.