Influence of Contaminations and Cleaning Sequences on Alkaline Texturisation

In this paper, the influences of contaminations and cleaning sequences on the alkaline texturisation were investigated. The silicon surface was specifically exposed to organic and metallic contaminations to study their influences on the alkaline texturisation process. Contaminations can occur as particles, films or gases, which can be deposited on the surface e.g. by the multi-wire slurry sawing, wafer storage or transport. Possible contaminations are organic compounds like slurry, glue, synthetics or etch resist and metals. The different influences on the alkaline texturisation and their were investigated. The results are quantified by confocal microscopy images, weighted reflection, surface roughness and surface enlargement. Therefore, it could be shown that the inorganic contamination has only a samll influence on the pyramid density, but no influence on macroscopic parameters, while organic contamination like glue residuals or etch resist showed critical problems and can inhibit the alkaline texturisation process.