[20p-E314-1~14] 16.3 Bulk, thin-film and other silicon-based solar cells

▲ [20p-E314-8] Microparticle-Assisted Texturing (MPAT) Process: Almost One Order Cost-Reduction, and Toward Mass Production of Low-Cost and High-Performance Crystalline-Silicon Solar Cells

〇(PC)Cong Thanh Nguyen¹, Keisuke Ohdaira¹, Hideki Matsumura¹ (1.Japan Advanced Institute of Science and Technology (JAIST))

Keywords:MPAT, Silicon, Surface cleaning

We aim to clarify whether the Microparticle-Assisted Texturing (MPAT) process is realistic in the mass-production of low-cost and high-performance thin crystalline silicon (c-Si) solar cells. Note that the MPAT process can quickly (<a few minutes) produce textured c-Si with reflectivity as low as 7%, a near record value for random textures. For such purpose, we developed the followings: high-yield MPAT process for multiple full-size as-cut n-type c-Si wafers, low-cost surface cleaning for multiple c-Si wafers, high-quality surface passivation, and effective anti-reflection coating. A low-cost dedicated MPAT machine for the multiple wafers processing was designed and fabricated, giving high-yield texturing (almost 100%), and a small standard deviation of the optical reflectivity <0.1% from wafer-to-wafer, and also from position-to-position in the same wafer. Surface cleaning of multiple wafers was also possible, and after surface passivation, the record effective minority carrier lifetimes of 7.2 ms, corresponding to the surface recombination velocity (SRV) of 0.38 cm/s. After anti-reflection coating (ARC), the reflectivity is as low as 0.5% at 600 nm wavelength, and <2% in a wide range of 450−950 nm. Therefore, the MPAT process is promising for mass-production.