Ultrafast laser direct hard-mask writing for high performance inverted-pyramidal texturing of silicon

We demonstrate a simple and versatile laser assisted technique to produce an inverted pyramid texture in monocrystalline silicon to reduce surface reflectance. With this method the inverted pyramid size, distribution, spacing, and hence the spectral reflection of the textured surface can be tailored. The process removes minimal amounts of silicon during the texturing process, thus making it compatible with ultra-thin silicon photovoltaics. Surfaces with the fabricated inverted pyramid texture and an antireflection coating reflect 4% of incident light.