GaAs photovoltaics and optoelectronics using releasable multilayer epitaxial assemblies

Flexible GaAs semiconductors Although compound semiconductors like gallium arsenide have a substantial performance advantage over silicon in photovoltaic and optoelectronic applications, these do not outweigh the costly process of growing large, high-quality layers of these materials and transferring them to flexible or transparent substrates for use in devices such as solar cells, night vision cameras and wireless communication systems. But now John Rogers and his team demonstrate a new fabrication approach that may remove this disadvantage. They grow films of GaAs and AlGaAs in thick, multilayered assemblies in a single deposition sequence, then release the individual layers and distribute them over foreign substrates by printing. The technological potential of this strategy to large-area applications is illustrated with the fabrication of GaAs devices such as field-effect transistors on glass and photovoltaic modules on sheets of plastic.