On the Design and Optimization of Three-Terminal Light-Emitting Device in Silicon CMOS Technology

The fabrication and performance of a MOSFET-like silicon light source that is able to monolithically integrate with silicon photo-detector in standard 3-μm CMOS process technology is introduced. The relation between gate voltage V_g and the breakdown voltage BV of the p-n junction in the gate-controlled diode is simulated to show that the modulation of light intensity can be reasonably explained by the decrease in BV, since the reverse-bias of the junction is fixed and the relation between the reverse current flowing through the p-n junction and the light intensity is linear. Based on such linearity, the paper attempts to explain the physical mechanisms responsible for the light emission in Si as a function of hot-carrier distribution functions. In order to further investigate the optical properties, measurement of photon emission and reverse current in silicon gate-controlled diode in avalanche breakdown has been made using electrical and near-infrared microscopy.