A New Additive-free Industrial Chemical Texturing Process for Diamond Wire Sawn mc-Si Wafers
A novel low cost process for texturing the diamond wire sawn (DWS) multi-crystalline silicon (mc-Si) wafers is demonstrated. The proposed scheme does not use any additives or metals and can be integrated into any standard industrial acid texturing tool. This process can be carried out at temperature ranges from 13–17 °C, which is normally higher than the temperature used for the conventional acid texturization process and thus making the process energy efficient. In this work, authors use HF rich acid solution for the generation of the porous silicon (Por-Si) layer, it is then followed by Por-Si dilution in an alkali solution. Process generates less porous, inverted rounded structures on the mc-Si wafer surfaces with excellent light trapping properties. Textured surfaces yield weighted average reflectance of 22.5% combined with a minority carrier lifetime up to 60 μs.
This work was carried out at the National Centre for Photovoltaic Research and Education (funded by the Ministry of New and Renewable Energy, Government of India) under the project no. 16MNRE002 at IIT Bombay.
- 4.P.K. Basu, K.P. Sreejith, Indian patent application no. 201721022615Google Scholar