Screen printed phosphorus diffusion for low-cost and simplified industrial mono-crystalline silicon solar cells

Screen-printing is considered to be the most efficient technique for large-scale Si solar cell production. Doping technique currently in use, such as POCl3 diffusion furnace, H3PO4 spray doping and spin-on-doping (SOD) tend to be time-consuming and wasteful of source materials. printing technology can be used for the application of doping substance for diffusion. Diffusion paste doping by the support of screen printing has enough potential to overcome the disadvantages of other doping techniques. This paper demonstrates a simple method for creation of P–N junction, with efficiency above 16.1%, using a screen printable phosphorus diffusion paste. To optimize the doping process using screen printing, we varied several experimental conditions, including firing temperatures and time. A fill factor above 77% has been reached, with an efficiency of 16.1% in a 10.0 cm×10.0 cm. The high fill factor with paste doping is mainly due to a contact resistance (3.53 Ω) lower than that for POCl3 (5.64 Ω). These results could be applied to the manufacturing of low cost, simplified and high efficiency Si solar cells.