Development of an AC-coupled silicon pad array detector

Abstract

Large area silicon pad arrays are used in many applications such as high energy physics and cosmic ray experiments, and radiation monitoring/imaging. AC-coupled silicon pad arrays are designed and fabricated. The measured electrical characteristics show good results. The signal readout electronics and data acquisition systems for the electric signals and data analysis are developed. The analog signal from the array sensors is processed by a VATA analog chip. The signal-to-noise ratio is measured to be 20.1 on average after coherent noise subtraction. Phantoms of a copper thin foil with a cross-shaped hole and of a 3-mm thick lead plate with diamond and cross shapes are prepared for imaging measurements. The phantom image is taken by using a radioactive source and proton beam. Optimization analysis are performed to improve the image quality. The performance results show that the developed silicon pad array detector can be used for charge and energy profile measurements of incoming particles in physics applications and for a radiation imaging detector.