The application of InP and related low-bandgap, III-V alloys grown by atmospheric pressure metalorganic vapor phase epitaxy (APMOVPE) to photovoltaics is discussed. The work is presented in two parts: the first is aimed at increasing the performance of InP shallow-homojunction cells via improved emitter designs, and the second concerns the development of InP-related low-bandgap ternary and quaternary compounds, and fabrication of solar cells therein. The emitter design study focussed on the majority and minority carrier transport properties of S-doped InP epilayers. This study has resulted in InP shallow-homojunction cells exhibiting substantial improvements in blue response. However, compensating losses in open-circuit voltage and fill-factor prevented overall gains in cell conversion efficiency. The development of solar cells in epilayers of InAsyPi1-y, Ga0.47In0.53As and GaxIn1-xAsyP1-y as applied to tandem solar cells is also discussed. Low-bandgap cells with good performance have been fabricated and areas for futher improvement have been outlined.
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