Two-dimensional single-crystal nanowire arrays

An extension of the superlattice nanowire pattern transfer (SNAP) that allows to construct arbitrary complex, two dimensional (2D) NW structures, templated on a sinle-crystal substrate at sublithographic dimensions is presented. The production of 2D Si NW logic and routing circuits at sublithographic dimensions involves combining of the SNAP process and other patterning techniques such as electron beam lithography (EBL). The monolithic 2D structure was employed to suspend ultra-high density NW arrays and to prepare regularly spaced nanometer-scale holes within in a single-crystal Si layer. The diameter of the nanohole arrays can be adjusted to the pitch of the templating superlattices and the spacing between holes can be tuned by adjusting the width of the NWs. Various alternative methods have been developed to avoid damage that include the formation of metal silicides at the NW S and D contacts.