Vertical group III-V nanowires on si, heterostructures, flexible arrays and fabrication

A method for direct heteroepitaxial growth of vertical III-V arsenide, phosphide or nitride semiconductor nanowires on a silicon substrate having a native oxide, the method comprising:

• etching the silicon substrate to remove the native oxide;
• promptly placing the silicon substrate in a reaction chamber after said etching and without any pre-deposited material on a surface of the silicon substrate but with some native oxide reformation to create a non-uniform native oxide on the silicon substrate;
• raising the temperature of the substrate without any pre-deposited material on the surface to a III-V arsenide, phosphide or nitride growth temperature;
• introducing Group III-V precursors of the arsenide, phosphide or nitride for a growth time to form the vertical III-V arsenide, phosphide or nitride semiconductor nanowires on the surface of the silicon substrate without any pre-deposited material on the surface by allowing self-assembled Group III-V arsenide, phosphide or nitride islands to nucleate confined by the non-uniform native oxide and then continue to grow into the vertical III-V arsenide, phosphide or nitride semiconductor nanowires;
• terminating the flow of the Group III precursor after the growth time;
• and
• retaining flow of the Group V precursors of the arsenide, phosphide or nitride during a cool down period.

A method for direct heteroepitaxial growth of vertical III-V arsenide, phosphide or nitride semiconductor nanowires on a silicon substrate having a native oxide, the method comprising:

• etching a surface of the silicon substrate with a buffered oxide etcher to produce a hydrogen terminated clean surface on the silicon wafer;
• rinsing the hydrogen terminated clean surface with de-ionized water;
• drying the hydrogen terminated clean surface in nitrogen;
• maintaining the clean surface and placing the silicon substrate with the hydrogen terminated clean surface promptly in a Metal-Organic Chemical Vapor Deposition (MOCVD) reactor, wherein the hydrogen terminated clean surface includes reformed non-uniform native oxide;
• heating the silicon substrate with the hydrogen terminated clean surface to a Group III-V arsenide, phosphide or nitride growth temperature and maintaining the silicon substrate at the Group III-V arsenide, phosphide or nitride growth temperature;
• introducing Group III-V precursors of the arsenide, phosphide or nitride separately into the MOCVD reactor over the clean surface via a showerhead port proximate the clean surface while maintaining a constant pressure in the MOCVD reactor and the silicon substrate at the Group III-V arsenide, phosphide or nitride growth temperature, and continuing the introduction for nucleation confined by the non-uniform native oxide and subsequent growth of vertical Group III-V arsenide, phosphide or nitride semiconductor nanowires for a period of a few seconds for the nucleation followed by growth time of the Group III-V arsenide, phosphide or nitride semiconductor nanowires up to about 5 minutes, wherein the showerhead port vertically introduces the Group III-V precursors of the arsenide, phosphide or nitride separately and uniformly through a plurality of ports over a deposition area on the silicon substrate.