Fabrication of nano-scale high aspect ratio ultra sharp tips for nano-mechanical structures at low thermal budget

In this paper, we demonstrate a novel approach to form ultra-sharp high-aspect-ratio and high density nanotips at low temperature suitable for integration with nano-electro-mechanical structures in CMOS compatible manner. For the first time, Cr thermally evaporated Spindt tips have been studied and achieved a tip radius as small as 3nm. An array of 250nm wide and 4μm tall nanotips have been fabricated with a high aspect ratio of 16 and high density of 1×10⁹ tips/cm². Furthermore, 250nm wide, 1.2μm tall tips have been integrated onto an array of 500nm wide silicon nanowires with high precision and yield. Potential application of the approach includes the development of high-speed parallel AFM on single chip.