Solar Cells

Among the promising candidates for the top solar cell are perovskite, organic PV, copper indium gallium selenide (CIGS), copper zinc tin sulfide (CZTS) and III-nitride semiconductors. III-nitride semiconductors possess wide band gap, are stable and exhibit superior light absorption. Indium gallium nitride (InGaN) alloys exhibit unique and promising properties such as high absorption coefficient (105 cm-1), direct band gap with energy spanning across 0.65 eV (InN) up to 3.42 eV (GaN) which covers the entire solar spectrum. Besides, the alloys demonstrate high thermal, high chemical stability as well as high radiation resistance. Furthermore, InGaN alloys have also been investigated intensively for applications in high-performance light emitting diodes (LEDs). These properties render InGaN alloys as a promising candidate as the top cell in high-efficiency InGaN-on-silicon solar cells. 

Institute of Nano Optoelectronics Research and Technology (INOR), Universiti Sains Malaysia, has been working on InGaN-based solar cells via INSOL project (PHC Hibiscus Grant #43850PK), which involves a research collaboration between LMOPS-UL/France and INOR-USM/Malaysia, which started in 2019. From the INSOL project, a novel Schottky structure has been developed based on a thick InGaN/GaN heterostructure with In% of up to 18% without phase separation or composition inhomogeneities. This structure paves the way to realise efficient InGaN p-n junction solar cell in the future.