Photocurrent and surface recombination mechanisms in the $In _xGa _{1-x}$N/GaN different-sized quantum dot solar cells

Abstract

We present a p-i-n structured solar cell with stacked layers of $In _xGa _{1-x}$ N Quantum Dots (QDs) with different indium composition. The photocurrent and surface recombination processes are investigated in the i-region. We have shown that the QDs in the i-region can play the role of both generation or recombination centers. The photocurrent has been calculated by self-consistent method to solve continuity equation of charge carriers in the layers of the i-region. By changing the Indium composition in Inx Ga1−x NQDs,the band gap of QDs varies and therefore provides a considerable overlapping with solar spectrum. Proposed SC with different-sized QDs and different Indium composition leads to absorption of a desirable wavelength range of solar spectrum and therefore a “rainbow” solar cell can be designed.