In order to scan a surface with high-step micro-features non-destructively and accurately, a novel tapping-mode stylus fabricated with a strip of thin piezoelectric polyvinylidene fluoride (PVDF) film is proposed. Besides the flexible piezoelectric PVDF film, the stylus also consists of a piezo-actuator, which actuates the PVDF strip to vibrate near its resonant frequency, and a tungsten probe which adheres under the PVDF film. The vibrating PVDF film acts as both the cantilever and the vibrating deflection detector as used in a tapping-mode atomic force microscope. Operated with an X–Y scanner, the tapping stylus can scan the surface like a tapping-mode scanning probe microscope.

In this paper, the structure and mechanism of the stylus is explained and an evaluation of the stylus is estimated: the maximum error and standard deviation along the vertical direction are about 2.0 and 0.5 nm respectively; the spring constant of the PVDF is experimentally estimated to be about 183 N m⁻¹. Due to the flexibility of the PVDF film and the large aspect of the tungsten probe, the stylus can scan surfaces with high steps non-destructively. Compared with a tapping-mode AFM, the structure of the stylus is simpler because the PVDF strip acts as both the cantilever of the AFM and its vibration-detecting sensor, which is usually an optical lever and photodiodes. In addition, the tungsten tip is anti-wear and there is no optical error.