Sievert, W.; Zimmermann, K.-U.; Hartmann, B.; Klimm, C.; Jacob, K.; Angermann, H.: Surface texturization and interface passivation of mono-crystalline silicon substrates by wet chemical treatments. Solid State Phenomena 145-146 (2009), p. 223-226
10.4028/www.scientific.net/SSP.145-146.223
Abstract:
The photovoltaic process requires a surface modification of the Si substrate in a way that the reflec-tion of light is reduced to a minimum and the generation of electrical energy is maximized. Wet chemical treatment is still state-of-the-art to texturize the surface of silicon. This paper reports on investigations of alternative wet etching processes [ ] developed at the Honeywell TSD lab in Seelze in order to improve the economics in manufacturing of mono-crystalline solar cells. The resulting surface properties were compared to the parameters obtained on randomly distributed up-side pyra¬mids, textured by a standard anisotropic etching treatment in alkaline solution [ ], carried out in the lab of the department of Siliziumphotovoltaik of Helmholtz-Zentrum Berlin für Materi-alien und Energie. The relations between structural imperfections at Si surfaces, light trapping be-haviour and interface state densities were investigated by scanning electron microscopy (SEM), surface photovoltage (SPV) [ ] and total hemispherical UV-NIR-reflectance measurements.