Reference: L Gourdeas, DA James, NP Davey, A Home-baked Temperature-Compensated Integrated Light Sensor on Silicon, Proceedings of SPIE 5274, 523
Abstract: Integrated smart sensors are quickly becoming an industry norm and often require multi-stage, multi-skilled design. This paper describes the fabrication of a temperature compensated light sensor using only a basic fabrication laboratory. A complete description of how to build the sensing elements, support electronics and communications is described and test results are presented. The construction of a light sensor using a shottkey barrier diode between the nickel and n-type silicon has been previously described by the authors. In this two such sensors are used as active and passive sensor elements to compensate for temperature effects. The outputs from each are differentially amplified, conditioned and buffered using an LM324 die to provide a temperature compensated output. Further reduction in size is possible when the temperature sensors are mounted front to back on a single silicon substrate and coupled directly to the LM324 die. External communications are only power, ground and an analogue signal.