17.6 Conversion efficiency multicrystalline silicon solar cells using the reactive ion etching with the damage removal etching

For lower reflectance, we applied a maskless plasma texturing technique using reactive ion etching (RIE) on acidic-textured multicrystalline silicon (mc-Si) wafer. RIE texturing had a deep and narrow textured surface and showed excellent low reflectance. Due to plasma-induced damage, unless the RIE-textured surfaces have the proper damage removal etching (DRE), they have a drop in V_ocand FF. RIE texturing with a proper DRE had sufficiently higher short circuit current (I _sc) than acidic-textured samples without a drop in open circuit voltage (V_oc). And in order to improve efficiency of mc-Si solar cell, we applied RIE texturing with optimized DRE condition to selective emitter structure. In comparison with the acidic-textured solar cells, RIE-textured solar cells have above 200mA absolute gain in Isc. And optimized RIE samples with a DRE by HNO₃/HF mixture showed 17.6% conversion efficiency, which were made using an industrial screen printing process with selective emitter structure.