Isotropic plasma texturing of mc-Si for industrial solar cell fabrication

Plasma texturing has been an active area of research for many years mainly focussing on the optimization of the surface morphology to reduce overall reflection losses. Most of these studies have been carried out on laboratory-type etching systems suitable for single wafer treatment. Within this work, plasma texturing of multicrystalline (mc) silicon for industrial application with a dynamic plasma etching system is presented. For an evaluation of achievable surface morphologies, the influence of the oxygen content of a SF6/O2 etch gas mixture has been investigated. With an optimized process, the created surface textures result in weighted reflectance values on mc-Si below 15 %. First cell results show significantly higher short circuit currents and approximately 3 % relative higher conversion efficiencies compared to wet chemically etched non-textured standard industrial mc-Si solar cells.