Investigation of a solid-state photodetector

We present results on the operation and performance characteristics of the MRS (metal/resistor/semiconductor) photodiode. These include measurements of threshold characteristics, noise frequency, dependence of signal amplitude on the applied voltage and temperature, and stability as a function of time and radiation dose. The single photoelectron separation for this photosensor is demonstrated with a light emitting diode. The response of the photodetector to light produced in a scintillator is studied with cosmic ray muons and a 106Ru source. In addition, fiber-sensor alignment issues were evaluated. The results are promising and illustrate the potential use of MRS as photosensors in high-energy physics detectors.