Randomly oriented indium phosphide nanowires for optoelectronics

The concept of randomly-oriented semiconductor nanowires formed on non-single-crystal substrates is introduced and compared with semiconductor nanowires synthesized on single-crystal-substrates in the framework of epitaxial growth. In principle, epitaxial growth of semiconductor nanowires with the presence of metal-catalysts requires no single-crystal substrates owing to the small size of nanowires. A segment on a substrate from which crystallographic information is transferred to a single nanowire would only need to be as larger as the cross-section of a nanowire if a specific geometrical alignment for a group of nanowires is not required, suggesting that randomly-oriented semiconductor nanowires be formed on a surface that is characterized with short-range atomic order in contrast to long-range atomic order that exists on the surface of single-crystal substrates. The surfaces exhibiting short-range atomic order can be prepared on non-single-crystal substrates, further suggesting functional devices that utilize randomly-oriented semiconductor nanowires be fabricated on non-single-crystal substrates. Design, fabrication and characteristics of a photoconductor that utilizes an ensemble of randomly-oriented indium phosphide nanowires are described.