US Patent 7858965 - Ge/Si nanowires

http://www.freepatentsonline.com/7858965.html

One problem with semiconductor nanowires in electronics is the formation of Schottky barriers which inhibit conduction at the interface between metal contacts and the nanowires. This patent is based on research from Charles Lieber's group at Harvard and teaches using nanowire heterostructure with a germanium core and silicon shell to help eliminate Schottky barriers. Claim 1 reads:

1. An electronic device, comprising:

a nanoscale wire consisting essentially of a core consisting essentially of undoped germanium and a shell surrounding the core consisting essentially of undoped silicon, the shell in physical contact with a first contact consisting essentially of nickel metal and a second contact,

wherein the shell of the nanoscale wire and the nickel metal contact form a Schottky barrier of less than 0.5 eV, and

wherein the nanoscale wire exhibits ballistic transport when subjected to a voltage via the first and second contacts.