Fabrication, Microstructural Characterization, and Internal Photoresponse ofPlatinum Silicide/P-Type Silicon and Iridium Silicide/P-Type Silicon Schottky Barrier Photodetectors for Infrared Focal Plane Arrays

摘要

Two dimensional staring arrays of PtSi/p-Si Schottky barrier photodiodes haveproven their effectiveness in high-resolution infrared imaging applications over the past decade. The ease with which highly uniform arrays can be fabricated using standard silicon planar processing techniques provides a definite advantage over competing technologies. However, the maximum quantum efficiency which these detectors have achieved is at best a few per cent in the region of interest. This fact has motivated studies of both fundamental limitations governing Schottky detector performance and the potential for increasing the quantum efficiency through process optimization. In this dissertation, the basic concepts, merits, and problems associated with the use of Schottky photodetectors for infrared imaging are outlined. The mechanisms which determine the photoresponse of an array element are discussed with the aid of a model developed during the course of this work. The model resembles that used to describe thermal diffusion yet incorporates the effects of energy losses due to phonon emission and the energy dependence of both the barrier transmission function and the scattering parameters.