(a) SEM images of a NeedleProbe with simple cylindrical geometry. (b) Schematic o the AFM experimental setup for liquid probing using NeedleProbe. (c) Top: schematic of the meniscus formation between the NeedleProbe and the liquid surface. Bottom: Typical force vs. distance (F-D) curve of the NeedleProbe on a liquid surface. The red line is extension and the blue line is the retraction force curve.
Enhanced EFM subsurface imaging of 0.5% SWCNT (LA)–polyimide nanocomposite film using an HAR probe. EFM bias voltage
and lift height is 12 V and 50 nm, respectively. (a) SEM image of a conventional probe, (b) SEM image of an HAR probe. Inset: enlarged
image of circled area near tip apex. (c) and (d) EFM phase image of subsurface CNTs using a conventional and HAR probe, respectively.
(e) and (f) Cross-section analysis of segmented line at (c) and (d), respectively. EFM phase scale 20◦. The EFM phase signal at circled peak in
(f) is both stronger and sharper than that in (e).