Application of Amorphous Silicon Thin-Film Position-Sensitive Detector to Optical Rules

Lateral photovoltage measurements in hydrogenated amorphous silicon and silicon-oxygen thin films

“…If the diffusion lengths of minority and majority carriers are very different much in the case of hydrogenated amorphous silicon (a-Si:H) and its related alloys, individual charge profiles are created and high LPV is observed. First LPV measurements in intrinsic a-Si:H was reported in [1], later in hydrogenated amorphous germanium by Srivastava et al [2], in a-Si:H and lc-Si p-i-n devices [3][4][5][6] and other device structures [7,8]. Diffusion lengths deduced from other experiments help in elucidating observed position dependence of LPV [1,2].…”

Large Lateral Photovoltaic Effect in Metal-(Oxide-)Semiconductor Structures

“…Due to the fact its output of lateral photovoltage (LPV) changes linearly with light spot position, this effect can be used in position-sensitive detectors (PSDs) which can detect very small displacements [22–35]. The main area of application of PSDs is in precision optical alignment, such as biomedical applications, robotics, process control, medical instrumentation, and position information systems [36–39].…”