Optoelectric properties of gainp p-i-n solar cells with different i-layer thicknesses.

Abstract

The optoelectric properties of GalnP p-i-n solar cells with different intrinsic layer (i-layer) thicknesses from 0.25 to 1 um werestudied. Both emission intensity and full width at half maximum features of the photoluminescence spectrum indicate that the optimum i-layer thickness would be between 0.5 and 0.75 um. The integrated current results of photocurrent experiment also point out that the samples with 0.5 to 0.75 um i-layer thicknesses have optimum value around 156 nA. Electroreflectance measurements reveal that the built-in electric field strength of the sample gradually deviates fromthe theoretical value largerwhen i-layer thickness of the sample is thicker than0.75 um. I-Vmeasurements also confirmcrystal quality forwhole samples by obtaining the information about short currents of photovoltaic performances. A series of experiments reflect that thicker i-layer structure would induce more defects generation lowering crystal quality.