Screen‐printed epitaxial silicon thin‐film solar cells with 13·8% efficiency

Abstract

Amidst the different silicon thin-film systems, the epitaxial thin-film solar cell represents an approach with interesting potential. Consisting of a thin active c-Si layer grown epitaxially on top of a low-quality c-Si substrate, it can be implemented into solar cell production lines without major changes in the current industrial process sequences. Within this work, $ 30-m-thick epitaxial layers on non-textured and highly doped monocrystalline Czochralski (Cz) and multicrystalline (mc) Si substrates have been prepared by CVD. Confirmed efficiencies of 13Á8% on Cz and 12Á3% on mc-Si substrates have been achieved by applying an industrial process scheme based on tube and in-line phosphorus diffusion, as well as screen-printed front and back contacts fired through a SiN x anti-reflection coating. An extensive solar cell characterisation, including infrared lock-in thermography and spectral response measurements is presented.

Epitaxial Thin Film Crystalline Silicon Solar Cells on Low Cost Silicon Carriers

“…Efficiencies up to nearly 14 % on Czochralski-silicon (Cz-Si) and 13 % on highly doped multicrystalline Si substrates have been achieved by applying an industrial process scheme based on tube or in-line P diffusion, as well as screen-printed front and back contacts fired through a SiN x anti-reflection coating [81,82]. Light-beam induced current measurements show that the diffusion length distribution is quite inhomogeneous over the whole cell area.…”

n‐Type emitter epitaxy for crystalline silicon thin‐film solar cells

“…For example, the screen-printing of the contact grids and the antireflection coating (ARC) can be transferred without significant modifications. 2 Only a few changes to the cell process, such as the adjustment of the firing temperature, are needed in order to introduce this concept in an industrial application. In addition, there are even procedures to simplify the solar cell process.…”