Electrophysical Properties of GaAs P–I–N Structures for Concentrator Solar Cell Applications

Abstract

This paper is dedicated to electro-physical characterisation of a GaAs p-i-n structure grown for solar cell applications, which was carried out by light and dark current-voltage ( I-V ) and Deep Level Transient Fourier Spectroscopy (DLTFS) methods. The conversion efficiency and open-circuit voltage were determined from I-V measurement at 1 and 20× sun light concentrations. Three electron like defects TA n1 , TA n2 , TD n and one hole like defect TBp obtained by DLTFS measurements were confirmed. The origin of these defect states was stated as native GaAs impurities.

Analysis of Current Transport Mechanism in AP-MOVPE Grown GaAsN p-i-n Solar Cell

“…The sign of each peak indicates whether the observed defect acts as a trap for minority or majority carriers, while the measured capacitance is proportional to defect concentration. DLTS-based methods are very efficient in defect determination in different semiconductor materials and devices, such as diodes [85,86], Schottky diodes [68,69] and rectifiers [87,88], solar cells [5,89,90], bipolar [91] and HEMT transistors [92] or laser structures [93,94]. A digital modification of DLTS, the deep level transient Fourier spectroscopy (DLTSFS) method measures the complete capacitance transient as a C(t) array and transfers the data into a computer system.…”