Au/GaAs photovoltaic structures with single-wall carbon nanotubes on the microrelief interface

Abstract

The effect of single-wall carbon nanotubes nanolayer on photoelectric properties of Au/n-GaAs photovoltaic structure with a microrelief interface has been investigated. Microrelief interfaces of dendrite-like and quasi-grating type aimed at enhancement of photocurrent have been prepared by the wet chemical anisotropic etching of GaAs. Carbon nanotubes obtained using the arc-discharge method were deposited on GaAs surface modified with poly(vinylpyridine) by dip-coating repeated several times. Optical, photoelectric and electrical properties of Au/GaAs structures have been studied in dependence on the averaged thickness of nanotubes nanolayer. Considerable photocurrent enhancement has been determined for structures with both the flat and textured interface but with a different optimal thickness of nanotubes layer. The effect was concluded to be caused by increasing the lateral photocurrent component due to enlargement of the current collection area and increase of the light trapping.