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 AJAC  Vol.5 No.3 , February 2014
Online Process Control of Alkaline Texturing Baths: Determination of the Chemical Concentrations
Abstract: Almost every monocrystalline silicon solar cell design includes a wet chemical process step for the alkaline texturing of the wafer surface in order to reduce the reflection of the front side. The alkaline texturing solution contains hydroxide, an organic additive usually 2-propanol and as a reaction product silicate. The hydroxide is consumed due to the reaction whereas 2-propanol evaporates during the process. Therefore, the correct replenishment for both components is required in order to achieve constant processing conditions. This may be simplified by using analytical methods for controlling the main components of the alkaline bath. This study gives an overview for a successful analytical method of the main components of an alkaline texturing bath by titration, HPLC, surface tension and NIR spectrometry.
Cite this paper: M. Zimmer, K. Krieg and J. Rentsch, "Online Process Control of Alkaline Texturing Baths: Determination of the Chemical Concentrations," American Journal of Analytical Chemistry, Vol. 5 No. 3, 2014, pp. 205-210. doi: 10.4236/ajac.2014.53025.
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