Performance Improvement of Quantum Well Infrared Photodetectors Through Dark Current Reduction Factor

A device model for quantum well-infrared photodetectors (QWIPs) is studied. The developed model accounts for the self-consistent potential distribution. An analytical model for the calculation of dark current reduction factor (DCRF) and the signal to noise ratio (SNR) is presented using the Matlab environment. The aim is to reduce the dark current and improve the SNR by adjusting the device parameters such as spacing between the wells, bias voltage, and the operating temperature of these detectors. This model takes into account the donor concentration in the barriers and the concentration of electrons above the barriers that have little attention in the literature. In these devices, decreasing the amount of DCRF and increasing the SNR represents the main goal for the device improvements. From the proposed model, we concluded that the contact layer and space-charge slightly affect the dark current in QWIP with a large number of quantum wells (QWs). These effects are significant in the case of a moderate number of QWs.