Conductive atomic force microscopy C-AFM

A. Alexeev and J. Loos, Conductive atomic force microscopy (C-AFM) analysis of photoactive layers in inert atmosphere. Org. Electron., 9, 149 (2008). 

Diblock copolymers PEO-fo-PS have been prepared using PEO macroinitiator and ATRP techniques [125]. The macroinitiator was synthesized by the reaction of monohydroxy-functionalized PEO with 2-chloro-2-phenylacetyl-chloride. MALDI-TOF revealed the successful synthesis of the macroinitiators. The ATRP of styrene was conducted in bulk at 130 °C with CuCl as the catalyst and 2,2 bipyridine, bipy, as the ligand. Yields higher than 80% and rather narrow molecular weight distributions (Mw/Mn < 1.3) were obtained. The surface morphology of these samples was investigated by atomic force microscopy, AFM. 

FIGURE 8.16 Atomic force microscopy (AFM) images of the surfaces of PPy-DBSA films cast from solutions in (a) NMP, (b) DBSA/chloroform, and (c) prepared electrochemically. (From Song, K.T., Synthesis of electrically conducting soluble polypyrrole and its characterization. Ph.D. thesis, 2000. With permission.)... 

Atomic Force Microscopy (AFM) image acquisition AFM measurements were conducted on films cast on mica slides. The films were coated with selfassembling substances by immersion in the respective solutions at room temperature and stored at 4 C. AFM measurements were conducted in tapping mode on a Digital Instruments Dimension 3000 Scope, with a Nanoscope Ilia... 

A comparative study of ultrathin dielectric (an azo-compound) and ferroelectric (copolymer P(VDF-TrFE)) Langmuir-Blodgett (LB) films has been carried out by Electrostatic Force Microscopy (EFM). Films were poled locally by a strong d.c. field applied between a conductive tip of an Atomic Force Microscope (AFM) and the bottom A1 electrode. The electrically poled domain was studied by EFM using a weak a.c. electric field and a lock-in amplifier technique. Two modes, a contact and non-contact ones, allowed for the measurement of field a in the air gap between the film and the tip and the piezoelectric distortion of the film due to the d.c. field aligned spontaneous polarization. Simultaneously the topographic relief of the same area was imaged. The results confirm unequivocally a possibility to switch ferroelectric LB film locally by an AFM tip. 

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