Mr Yucheng Hu

Cu(In,Ga)S2 (CIGS) is a chalcopyrite material that is ideal for next generation thin film solar cells. Because of its direct and tunable bandgap, it can achieve a high absorption efficiency and light conversion efficiency. One particularly interesting observation about the material is that polycrystalline CIGS can achieve a higher energy conversion efficiency than the single-crystalline form. These interesting properties may be attributed to the special grain boundaries in CIGS, which are not present in sigle-crystaline CIGS. Further research on the structural, electrical, and opto-electrical properties of grain boundaries is required to reveal the physics behind the material.

The aim of my PhD project is to develop methods to understand the interplay between structural and opto-electrical material properties. My work will primarily focus on the correlation of cathodoluminescence and electron backscatter diffraction, which allows for investigating the influence of grain boundaries on the charge carrier recombination in CIGS. Further analysis techniques, such as scanning probe microscopy techniques, may also be used to enhance the understanding of grain boundaries' electronic properties.