BASIC TECHNOLOGIES FOR HIGH-PERFORMANCE SOLID-STATE IMAGE SENSORS FOR CIM APPLICATIONS

The next generation of image sensors for use in industrial applications require high resolution, high signal speed, low noise, good sensitivity and high resistance to blooming at over-exposure. Automated functional testing of sensors as well as image processing are important. ESPRIT Project 1572 has addressed the most limiting areas of the available technology with the aim of creating better solutions for advanced designs. With transparent conductive electrodes made of Indium-Tin-Oxide in exchange with polycrystalline silicon the overall sensitivity can he increased by a factor of two. A prototype of an automated functional test system for important operating parameters of sensors has been developed. By optimizing the peripheral electronic and output stage of the sensor, output amplifiers on chip were achieved functioning at a frequency of 20 MHz with a temporal noise of lower than 70 electrons. Antiblooming structures for smaller pixel dimensions have been simulated and realized for the horizontal structure. Blooming is suppressed up to 60 times the saturation light level. The study of image processing resulted in the proposal for preprocessing methods within the camera head, to relieve the main image processing host of significant computational load. © 1990 Taylor & Francis Group, LLC.