The team's goal was to design a hardware system that combines an ultrasound medical imaging device with additional imaging modalities. This new system will simplify the current procedure for more effective diagnosis, decrease preparation and cleaning times, and improve the experience for the patients.
We present a generalized study of light emission from reverse biased p–n junctions under avalanche breakdown conditions. A model is developed based on direct and indirect interband processes including self-absorption to describe measured electroluminescence spectra. This model was used to analyze experimental data for silicon (Si) and gallium arsenide p–njunctions and can be extended to several types of semiconductors regardless of their band gaps. This model can be used as a noninvasive technique for the determination of the junction depth. It has also been used to explain the observed changes of the Si p–n junction electroluminescence spectra after fast neutron irradiation. In particular, it is demonstrated that the neutron irradiation affects both the semiconductor and the overlying passivation oxide layer.