Conversion efficiency and process stability improvement of electron beam crystallized thin film silicon solar cells on glass

Abstract Liquid phase crystallization (LPC) using e-beam or CW-laser line sources of amorphous or nanocrystalline silicon films has emerged as new method to form high quality absorbers on cheap substrates. A disadvantage of electron beam crystallization was the necessity to use amorphous SiC x layers in contact with the silicon to maintain a stable crystallization process, resulting in high surface recombination. In this work we investigate capping layers to enable e-beam induced LPC on alternative interlayer materials especially SiO 2 and characterize the morphological and electrical properties of these layer stacks. Photoluminescence measurements of LPC absorbers on SiO 2 layers exhibit significantly increased radiative recombination compared to SiC x . Fabricated hetero-junction cells achieved a new emitter area efficiency record for electron beam induced LPC solar cells of 9% using the FrontERA contact system and H passivation.

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