Monocrystalline Silicon Solar Cell Diffusion Process And The Electrical Properties Of Simulation

With the rapid development of the crystalline silicon solar cell industry, process simulation of the crystalline silicon solar cells and device simulation of silicon solar cell electrical characteristics on PC computer are very important to explore new process technology, optimize process onsite and guide the industry production. The research demonstrates theoretical as well as practical values.Based on the silicon semiconductor theory, this paper studied the crystalline silicon solar cells model, and researched the effect on crystalline silicon solar cell electrical characteristics of each step sequence (oxidation, pre-diffusion and redistribution) of the crystalline silicon solar cell diffusion process,the main parameters (junction depth and surface concentration) of p-n junction and so on. This paper carried out the process simulation and device simulation of crystalline silicon solar cells on PC computer, set up the diffusion process simulation platform. By using the simulation platform, this paper simulated and optimized two typical silicon solar cell diffusion processes, and obtained electrical properties of the optimized structure and process.The results show that crystalline silicon solar cells produced by the diffusion process condition 1 get open circuit voltage of 0.6215V, short-circuit current of 3.545A, conversion efficiency of 18.15%; crystalline silicon solar cells produced by the diffusion process condition 2 get open circuit voltage obtained for the 0.6208V, short-circuit current is 3.489A conversion efficiency of 17.88%. The results which were basically consistent with the measured results verified the simulation method.After repeatedly optimizing on the verified simulation platform, we got the best process parameters. In this process parameter, monocrystalline silicon solar cell get open circuit voltage of 0.622V, short-circuit current up to 3.545A, conversion efficiency of 18.16%; and compared with the original process condition 1 could shorten the diffusion process time of 24 minutes. So it can significantly improve productivity. The specific optimized process parameters are as follows:With oxidation temperature 880℃and oxidation time 10 min, the flow rate of not carrying source N2 is 20000 ml/min, and the flow rate of O2 is 2000 ml/min; With pre-diffusion temperature 880℃and pre-diffusion time 19 min, the flow rate of not carrying source N2 is 2200 ml/min, and the flow rate of carrying source N2 is 2400 ml/min, the flow rate of O2 is 3000 ml/min;With re-distribution temperature 880℃and re-distribution time 8 min, the flow rate of not carrying source N2 is 20000 ml/min, and the flow rate of O2 is 3000 ml/min.