Evaluating the performance of InGaN/GaN multi-quantum-well solar cells operated at elevated temperatures via DC and small-signal AC analysis

Abstract

InGaN/GaN multi-quantum-well (MQW) solar cells are investigated with temperature-dependent DC and AC analysis, and the effects of differing QW number and thickness are determined. The carrier transport is shown to be dominated by thermionic emission rather than tunneling at elevated temperature but limited by recombination outside the depletion region. Temperature-dependent AC parameters of the III-N MQW devices in high-level injection are determined through a refined AC circuit model of the device. It is shown that the use of AC small-signal analysis and its ability to extract stored charge in the QWs, the comparison of built-in potential to VOC, and other solar cell critical values allows a device designer insight not possible via DC analysis alone. This critical data suggests that the number of QWs and total depletion volume needs to be matched to the operational temperature of a given high temperature solar cell.

Boosting Photovoltaic Efficiency in Double Quantum Well Intermediate Band-Solar Cells through Impurity Positioning

“…It is important to mention that according to theoretical [28,29] and experimental studies [14,19,30], thin films immersed in a semiconductor material can generate discrete energy levels for electron and hole states. In the scope of this investigation, a novel system is conceptualized wherein these states are effectively confined by the presence of a double quantum well composed of InAs.…”