Silicon surface texturization is required for high efficiency solar cells to reduce light reflectance. Anisotropic chemical etching utilizes a mixture of alkaline solutions and isopropyl alcohol (IPA) in typical pyramidal texture process. However, the volatile pollutant and the cost of IPA are important factors of overall texturization cost and environment reduction approach. In this paper, we investigate an alternative texture process by using a polytetrafluoro-ethylene (PTFE) grids-based texturization approach of monocrystalline silicon wafers with potassium hydroxide (KOH) is proposed. The suitable openings and separation between the close contact of the PTFE grids and silicon surface are used to capture hydrogen bubbles and breach them from the surface, which leads to form random pyramid structures in the silicon surface. Using an optimized conditions this etching process with free IPA provided a low weighted reflectance of 11.82% without any anti-reflectance coating.
Thipwan Fangsuwannarak, Suranaree University of Technology, Thailand
Stream: Energy: Renewable Energy and Environmental Solutions
This paper is part of the ACSEE2015 Conference Proceedings (View)
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