Polarization-Engineered InGaN/GaN Solar Cells: Realistic Expectations for Single Heterojunctions

The photovoltaic properties of (0001) n-InGaN/p-GaN single heterojunctions were investigated numerically and compared with those of conventional p-GaN/i-InGaN/n-GaN structures, employing realistic material parameters. This alternative device architecture exploits the large polarization fields, and high efficiency modules are achieved for In-rich, partially relaxed and coherently strained InGaN films. Conversion efficiencies up to 14% under AM1.5G illumination can be reached, revealing the true potential of InGaN single junction solar cells with proper design.