The alternative is using thin film photovoltaics. They use thin layers of specific p-type and n-type materials sandwiched together and utilize the photovoltaic effect. This technology allows manufacturing more panels for a lower price.
The only problem with this technology is their use of toxic and rare materials. Hence, a Tokyo Institute of Technology research team tried to find alternative materials for producing cleaner and cheaper thin-film photovoltaics.
They found that copper nitride can act as an n-type semiconductor, and with fluoride doping, it can be used as a p-type semiconductor. Copper nitride is a simple binary compound that is composed of environmentally friendly elements. However, another challenge appeared: growing a nitride crystal in a high-quality form is very hard. Therefore, the research team found another way to produce the nitride: catalytic reaction route using ammonia and oxidant gas.
All existing thin film photovoltaics require a p-type or n-type partner to make a sandwich structure. Thus, finding the best combination requires huge efforts. The Tokyo Institute of Technology research team succeeded to design a highly efficient solar cell structure without such efforts.
They have not used any toxic materials in the production. Additionally, all of the materials are abundant, so the process will cost less. It is an ideal replacement for both conventional toxic thin film solar cells and crystalline silicon solar panels. With the development and massive production of these semiconductors, the benefits of thin film technology will further bring it into the light.