Thursday, August 30, 2007

US Patent 7262501 - Thin film semiconductor formed from p-type and n-type nanowires

Nanosys is one of three companies leading the way in alternative approaches to electronics (the others being Nantero and Hewlett Packard). The approach of Nanosys is to premanufacture semiconductor nanowires which are predoped to be n-type or p-type and then align the nanowires on a substrate to form electronic devices. The advantage of this approach is that it opens the door to many different substrates other than silicon (such as flexible and/or biocompatible material) from which to form sensors, photovoltaics, electronics, etc. In addition, lower cost fabrication can be achieved using printing technologies rather than the high temperature/low pressure conditions of modern fabs. This patent is directed to methods of making such nanowire electronics. Claim 1 reads:

1. A method of making a thin film for use in one or more semiconductor devices, comprising: (A) forming a first plurality of nanowires that are p-type; (B) forming a second plurality of nanowires that are n-type, wherein said forming comprises doping said second plurality of nanowires with an n-type dopant; (C) depositing the first plurality of nanowires on a first region of a substrate and second plurality of nanowires onto a second separate, non-overlapping region of the substrate to form a thin film of nanowires that includes n-type and p-type nanowires; and (D) allowing the mixture of n-type and p-type nanowires to become immobilized on the substrate, whereby the thin film of nanowires exhibits characteristics of both n-type and p-type nanowires.