3% absolute efficiency gain on multicrystalline silicon solar cells by TiO2 antireflection coatings derived by APCVD process

Abstract

This paper reports about the adaptation of the CVD thin films technology to the fabrication process of multicrystalline silicon (mc-Si) solar cells which is the key issue of modern method of photovoltaic power generation. In this contribution, the higher reflection of a mc-Si solar cell surface is strongly reduced by the deposition of TiO2 antireflection coating (ARC) on the front using CVD method at atmospheric pressure (APCVD). The surface morphology and elemental composition of the TiO2 antireflective layers were revealed using Scanning Electron Microscopy (SEM) in conjunction with Energy Dispersive X-ray Spectroscopy (EDS). The reflectivity was then reduced from 35% to 8.6% leading to the increase of the short circuit current Jsc which was about 33.86 mA/cm² with a benefit of 5.23 mA/cm² (surface area = 25 cm²) compared to reference cell (without ARC). This simple and low cost technology induces a 14.26% conversion efficiency which is a gain of + 3% absolute in comparison to reference cell. These results are encouraging and prove the effectiveness of the APCVD method for efficiency enhancement in silicon solar cells.