Crystalline silicon solar cells with micro/nano texture

Crystalline silicon solar cells with two-scale texture consisting of random upright pyramids and surface nanotextured layer directly onto the pyramids are prepared and reflectance properties and I-V characteristics measured. Random pyramids texture is produced by etching in an alkaline solution. On top of the pyramids texture, a nanotexture is developed using an electroless oxidation/etching process. Solar cells with two-scale surface texturization are prepared following the standard screen-printing technology sequence. The micro/nano surface is found to lower considerably the light reflectance of silicon. The short wavelengths spectral response (blue response) improvement is observed in micro/nano textured solar cells compared to standard upright pyramids textured cells. An efficiency of 17.5% is measured for the best micro/nano textured c-Si solar cell. The efficiency improvement is found to be due to the gain in both Jsc and Voc.

► Combined micro/nano scale texture was produced on crystalline silicon surface ► The micro/nano scale texture features antireflection properties ► Solar cells with this texture are shown improved blue-response and conversion efficiency.