Forming submicron in micron texture on the diamond‐wire‐sawn mc‐Si wafer by introducing artificial defects

Abstract Based on a traditional acid etch system (i.e., HNO 3 /HF), a complex texture comprising microscale and submicroscale structures was produced on the surface of a diamond‐wire‐sawn (DWS) multicrystalline Si (mc‐Si) wafer, upon whose surface it is typically difficult to form an effective texture for suppressing the reflection of incident light. Immersing the as‐cut wafer into an HF/HNO 3 /AgNO 3 solution introduced a large number of artificial defects onto the wafer surface. A subsequent HNO 3 /HF etch induced a micron texture expanded from the original DWS‐induced damage as well as a submicron texture converted from the artificial defects. The multiscale textured DWS exhibited a reflectivity of ~19%, which is much lower than the reflectivity after only an HNO 3 /HF etch (~28%). Therefore, the solar cell performance was improved owing primarily to improved optical antireflection and surface passivation. The method is simple and can be easily scaled up into the in‐line texture process.