Investigation of the Cleaning Effects Regarding Organic Contaminants on the Alkaline Texturisation

In this paper the influence of organic contaminations on the alkaline textured surface is discussed. Furthermore, different cleaning sequences are investigated for their cleaning efficiency in the removal of organic contaminants. The common organic contaminations are particles, films or gas emission from plastics, which can be deposited on the surface during wafer storage, transportation, wafer handling or solar cell processing. Wafer surfaces were analysed first by thermal desorption followed by gas chromatography with mass spectroscopy (TD-GC-MS) to determine the organic contamination from the storage and transportation. The fingerprint as human organic residues on the silicon surface is additionally investigated. The silicon surface is exposed with specific estimated organic contaminations to analyse their influences on the alkaline texturisation process. The results are quantified by weighted reflection, confocal microscopy and flatbed images. It could be shown that organic contaminations like the analysed gas emissions from plastics have no influence on the homogeneity of the texture, while fingerprint residues show problems and can influence the alkaline texturisation process.