Fabrication of vertical nanopillar devices

Electron transport in silicon nanopillars has been investigated, with a view to developing vertical electron emission, electroluminescent and photoluminescent devices. Arrays of nanopillars were fabricated in highly-doped single crystal silicon and polysilcon materials. A ‘natural lithography’ technique utilising colloidal gold particles as an etch mask, in conjunction with standard microfabriction techniques, was used to fabricate the nanopillars in selected regions. The pillar height was 100 nm in single crystal silicon material and 40 nm in polysilicon material and the diameter of the pillars was 30 nm. A top contact was supported on a polyimide film, deposited by spin coating and curing, and then etching-back in oxygen plasma to expose the pillar tops. The current–voltage characteristics of these devices were measured at range of temperatures. 2007 Elsevier B.V. All rights reserved.