Our "grow-in-place" approach to Si nanowire devices uses a silicon precursor gas (e.g., SiH 4 ) to directly produce self-assembled, electrically contacted, crystalline Si nanowires without any intervening silicon material formation or collection/positioning steps. The approach uses the vapor−liquid−solid (VLS) growth mechanism and lithographically fabricated, permanent, nanochannel growth templates to control the size, shape, orientation, and positioning of the nanowires and ribbons. These horizontal templates are an integral component of the final devices and provide contacts, interconnects, and passivation/encapsulation. The approach results in self-assembly of the Si nanowires (SiNWs) and nanoribbons (SiNRs) into interconnected devices without any "pick-and-place" or printing steps, thereby avoiding the most serious problems encountered in process control, assembly, contacting, and integration of SiNWs and SiNRs for IC applications. As an initial demonstration of our approach, we have fabricated SiNW and SiNR resistors with built-in electrical contacts and encapsulation and report conductivity measurements.

We describe the use of hard etching methods to create nanodimensional channels and their use as templates for the formation of polymer filament arrays with precise dimensional and orientational control in a single integrated step. The procedure is general as illustrated by the radical, coordination, and photochemical polymerizations that were performed in these nanochannels. The nanochannel templates (20 nm high, 20-200 nm wide, and 100 mum long) were fabricated by the combined use of electron-beam lithography and a sacrificial metal line etching technique. Radical polymerization of acrylates, metal-catalyzed polymerization of norbornene, and photochemical polymerization of 1,4-diiodothiophene were carried out in these nanochannels. The polymers grown follow the dimensions and orientation of the channels, and the polymer filaments can be released without breaking. The approach opens up the possibility of just-in-place manufacturing and processing of patterns and devices from nanostructured polymers using well-established polymer chemistry.