Investigation on growth and electronic characteristics of vertical carbon nanotubes

Abstract

Carbon nanotubes (CNTs) as interconnects in integrated circuits (ICs) which are vertically aligned in growth with high tube density and long tube length are required. In this paper, we present a method to improve the height of CNTs. High-resolution transmission electron microscopic (TEM) images confirm CNTs top growth mode. By cutting and modifying the top of CNTs, the influences of different radii of apertures on interconnect resistance were studied. According to the analysis, we proposed a novel growth mechanism to improve growth height of CNTs interconnection structure and the top contact resistances of pre-cutting and post-cutting CNTs interconnection structure were forecasted. The result demonstrates that the electronic performances of the post-cutting CNTs interconnection structure with platinum (Pt)-protected layer are better than the ones of pre-cutting CNTs interconnection structure. The resistivity of the post-cutting CNTs interconnection structure with Pt-protected layer is [Formula: see text], which is much less than that of post-cutting CNTs interconnect structure [Formula: see text]. In what follows, the resistance of the contacted area of pre-cutting CNTs interconnection structure is 31 [Formula: see text], which is much less than that of post-cutting CNTs interconnection structure 439 [Formula: see text]. This constitutes a significant step to realize longer CNTs interconnects with complementary metal oxide semiconductor (CMOS) contact modules.