Millions of Nanocantilevers for Atomic Force Microscopy

Hideki Kawakatsu

Institute of Industrial Science, University of Tokyo

We have fabricated millions of single crystal silicon cantilevers with tips on a centimeter square chip by anisotropic etching of silicon by KOH. Small triangular cantilevers measuring 2 to 8ｵm in length and 30 nm to 100 nm in thickness were fabricated with a 5 to10ｵm spacing. Since the tips and the cantilevers are formed by anisotropic etching, the method is scalable, and cantilevers measuring from 100 nm to a few ｵm can be fabricated with high uniformity, well-defined shape and size. The Q factor of the cantilever was 10000 in vacuum and 5 in air. Its spring constant was 8 N/m. The natural frequency of the cantilever was 1.3 MHz and 5 MHz, depending on their size and thickness. The natural frequencies of the cantilevers within the same row differed only by 0.01 %. A wide range of cantilevers with different mechanical properties can be fabricated depending on the target application.