ZnO/c-Si Heterojunction Interface Tuning by Interlayers

Abstract

The junction properties of isotype and anisotype n+-ZnO/c-Si heterostructures have been studied by electrical and photoelectrical methods. We present evidence that the junction properties are strongly affected by a 10–30 nm thick ZnO layer closest to the heterointerface with distinctively different properties than those of the ZnO film bulk. This layer supports a dominant current flow via multistep tunnelling-recombination. When a 10 nm thin ZnS or ZnSe interlayer is inserted charge transport is controlled by thermionic emission. The interlayer acts as spacer and increases the band bending in the silicon absorber. However, there is still a too high trap density at the interlayer/c-Si interface, so that Voc does not exceed 0.25–0.32 V.

Preparation and Optoelectronic Characteristics of ZnO/CuO-Cu2O Complex Inverse Heterostructure with GaP Buffer for Solar Cell Applications

“…The buffer layer is a layer situated the absorber and the transparent conductive oxide. It should satisfy the following conditions: (1) a thin layer; (2) energy gap between the absorber and the transparent conductive oxide; and (3) lattice constant between the absorber and the transparent conductive oxide [ 16 ].…”

Electrical properties and carrier transport mechanisms of n-ZnO/SiOx/n-Si isotype heterojunctions with native or thermal oxide interlayers

“…It has been found that growth of a thin Si-oxide interlayer in SnO 2 /Si HJs or indium tin oxide (ITO)/Si HJs played an important role in improving the device performance [9][10][11]. For the ZnO/Si HJ system, ZnS and ZnSe have been introduced as an interlayer material for photovoltaic application [12]. ZnO/SiO x /c-Si HJs have been reported for light-emitting diodes [13], but experimental investigations on the influence of a thin Si-oxide interlayer on ZnO/SiO x /Si HJ properties are few [14].…”