Fabrication of ZnInON/ZnO multi-quantum well solar cells

• We fabricated solar cells with ZnInON MQWs in the intrinsic region of pin structure.
• J–V characteristics were measured under green laser and solar simulator light.
• The efficiency is enhanced by superimposing green laser.
• The long carrier lifetime contributes to carrier extraction from the well layers.

We report on fabrication and photovoltaic characteristics of solar cells with ZnInON/ZnO multi-quantum wells (MQWs) in the intrinsic layer of p-i-n structure by RF magnetron sputtering. We employed two kinds of p layers: one is p-GaN and the other is p-Si. Under solar simulator light, the short-circuit current (Jsc) and the open-circuit voltage (Voc) of the solar cells on p-GaN templates are 1.9 μA/cm2 and 0.16 V, whereas Jsc and Voc are enhanced to 2.5 μA/cm2 and 0.19 V under simultaneous irradiation of green laser light (532 nm) and the solar simulator light. Solar cells on p-Si substrates do not show such enhancement. A possible origin of the enhancement is a large piezoelectric field generated in strained ZnInON wells coherently grown on p-GaN template.