Light Source Position Measurement Technique Applicable in SOI Technology

Abstract

Integrated optical sensors make use of a p-n-junction for light intensity detection, typically. Because of the costs, additional optical components are not available in standard integration processes. Therefore, in higher level optical sensors extra optical components are not part of an integration. In this paper a concept for integration is proposed, which especially allows to measure the angles of a far distance light source relative to the surface of the chip and the coordinate system of the integrated structure. The invention makes use of the stack topology and the light opacity of metal layers in the monolithic integration, the light translucency of , and the electrical light sensitivity of diodes. Because of perfect device isolation the implementation can be done most advantageously in SOI CMOS technology. With minor modifications it is applicable in other integration technologies as well. But leakage currents and device mismatching will limit the obtainable performance additionally.