Research On A New Type "n～+-SnO₂/n-p-p～+-Si Solar Cell"

The development of the solar cells draw much attention on increasingly improving the efficiency and reducing the product cost. Based on the solar cell work principle , tandem solar cells that consist of a homojunction and a heterojunction are important solutions to this problem, which can achieve higher efficiency by relatively lower cost with different energy band materials and be designed well-matched according to semiconductor energy band engineering theory. The "n⁺-SnO₂/n-p-p⁺-Si solar cell" is a new type tandem solar cell which based on this idea.Firstly, theoretic design of "n⁺-SnO₂/n-p-p⁺-Si solar cell" energy band structure is strictly calculated and presented in this paper. Our conclusion is that the homeotypic heteroj unction energy band structure of n⁺-SnO₂/n-Si can achieve "slick" linking when light phosphorus doping concentration N_A=2×10¹⁷cm^-3 in n-Si region and SnO₂ is heavily doped. Secondly, we acqurie n-p-p⁺-Si chip according to our theoretic design by "spin-on" source diffusion technique, so light phosphorus doping concentration N_A≈5×10¹⁷cm^-3 in n-Si region is achieved . Thirdly, we prepare n⁺-SnO₂:F(Sb) transparenrt conductive thin films as cell's window layer and photovoltaic working layer. The films' thickness is approximately 100 nm and the film square resistance is 10 Ω /â–¡ .In the end, we make electrode system by vacuum evaporation technique and accomplish the integrated "n -SnO₂/n-p-p⁺-Si " solar cell.It should be emphasized that we accomplish the integrated "n⁺-SnO₂/n-p-p⁺-Si" solar cell all by traditional methods, such as thermal diffusion, alloying process, printed contact and spray pyrolysis etc. So, it is a integrated innovation of lower cost manufacture technique, and also can be esily achieved in mass production..