Role of n-ZnO Layer on the Improvement of Interfacial Properties in ZnO/InGaN p-i-n Solar Cells

摘要

In GaN has been predicted to be an efficient photovoltaic material. However, the high-density polarization charges and large potential barrier at the i-In GaN/nGaN interface create an electric field that severely decreases the collection efficiency of p-In GaN/i-In GaN/nGaN heterostructure solar cells. We demonstrate that,according to numerical simulations, utilizing a p-In GaN/iIn GaN/n-ZnO heterostructure can greatly reduce the piezoelectric field in the absorption layer and reduce the potential barrier between the n-type layer and the absorption layer interface, thus improving the performances of the solar cell. Moreover, we studied the influence of the band alignment on the ZnO/In GaN interface on the performance of the solar cell. We found that the band alignment of the ZnO/In GaN interface can keep the solar cells at a very high efficiency over a wide scope.