Experimental study and theoretical analysis of photoelectric characteristics of AlxGa₁₋xAs–p-GaAs–n-GaAs-based photoconverters with relief interfaces

Abstract

We studied experimentally the photoelectric characteristics of the AlxGa₁₋xAs–p-GaAs–n-GaAs structures with relief interfaces. A theoretical analysis of spectral dependences of internal quantum efficiency of short-circuit current in the above solar cells (SC) was performed. In particular, the low-energy spectral region (where absorption is weak) was considered. A comparison was made between the experimental and theoretical photocurrent spectral curves. From it, we determined a number of parameters of the AlxGa1–xAs and GaAs р-layers, as well as of the n-GaAs layers. Some recommendations concerning the ways to increase photocurrent and extend photosensitivity spectral region were developed for technologists. A theoretical analysis of a “spotty” model for open-circuit voltage formation in relief AlxGa₁₋xAs–p-GaAs–n-GaAs-based SC was made. This model enables one to give a qualitative explanation for decrease of open-circuit voltage in relief SC as compared to the case of flat interface.