Development of solution-derived diffusion barrier layer for back-contact crystalline silicon solar cell

In order to reduce the back-contact silicon solar cell manufacturing process cost, polysilazane solution is used to form SiO₂ diffusion barrier layer in this study. The thickness and refractive index of SiO₂ film is evaluated by spectroscopic ellipsometer measurement. Sheet resistance measurement and SIMS measurement revealed that polysilazane-derived SiO₂ layer presents excellent barrier effect for boron and phosphorous diffusion process, while SiO₂ deposited by plasma chemical vapor deposition is available for only phosphorous diffusion process.