High-performance Si microwire photovoltaics

作者：Kelzenberg Michael D^*; Turner Evans Daniel B; Putnam Morgan C; Boettcher Shannon W; Briggs Ryan M; Baek Jae Yeon; Lewis Nathan S; Atwater Harry A

来源：Energy & Environmental Science, 2011, 4(3): 866-871.

DOI：10.1039/c0ee00549e

Crystalline Si wires, grown by the vapor-liquid-solid (VLS) process, have emerged as promising candidate materials for low-cost, thin-film photovoltaics. Here, we demonstrate VLS-grown Si microwires that have suitable electrical properties for high-performance photovoltaic applications, including long minority-carrier diffusion lengths (L(n) >> 30 mm) and low surface recombination velocities (S << 70 cm.s(-1)). Single-wire radial p-n junction solar cells were fabricated with amorphous silicon and silicon nitride surface coatings, achieving up to 9.0% apparent photovoltaic efficiency, and exhibiting up to similar to 600 mV open-circuit voltage with over 80% fill factor. Projective single-wire measurements and optoelectronic simulations suggest that large-area Si wire-array solar cells have the potential to exceed 17% energy-conversion efficiency, offering a promising route toward cost-effective crystalline Si photovoltaics.

• 出版日期2011-3