Simulations, Practical Limitations, and Novel Growth Technology for InGaN-Based Solar Cells

Indium gallium nitride (InGaN) alloys exhibit substantial potential for high-efficiency photovoltaics. However, theoretical promise still needs to be experimentally realized. This paper presents a detailed theoretical study to provide guidelines to achieve high-efficiency InGaN solar cells. While the efficiency of heterojunction devices is limited to ~11%, homojunction devices can achieve suitable efficiencies, provided that highly p-type-doped InGaN layers and thick, single-phase InGaN films can be grown. Thus, we have developed a novel growth technology that facilitates growth of p-type nitride films with greatly improved hole concentration and growth of InGaN without phase separation, offering promise for future high-efficiency InGaN solar cells.