Fabrication of an ultrasharp and high-aspect-ratio microprobe with a silicon-on-insulator wafer for scanning force microscopy

Abstract

Articles you may be interested inHigh-stroke silicon-on-insulator MEMS nanopositioner: Control design for non-raster scan atomic force microscopy Rev. Sci. Instrum. 86, 023705 (2015); 10.1063/1.4907908High-aspect-ratio grooves fabricated in silicon by a single pass of femtosecond laser pulses J. Appl. Phys. 111, 093102 (2012); 10.1063/1.4709726 Fabrication of high-aspect-ratio lightpipesA microprobe having an ultrasharp and high-aspect-ratio stylus was made using a directly bonded silicon-on-insulator ͑SOI͒ wafer. The stylus and cantilever were made of 8 m-thick ͑100͒-Si film and 2 m-thick dioxide film of the SOI wafer with sufficient reproducibility. The cantilever is 100 m in length, 20 m in width, and 1.6 m in thickness; the stylus is 7 m in height with an aspect ratio exceeding 2. The stylus was formed first by reactive ion etching and sharpened by orientation dependent etching with KOH solution. The apex of the stylus is 10 nm in radius of curvature. The present microprobe was found adequate for atomic force microscopy ͑AFM͒ measurement with spatial resolution better than 10 nm in noncontact-mode topographic imaging. The mode of fabrication, mechanical properties of the microprobe, and results of AFM measurement are discussed.

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