ATOMIC-FORCE MEASUREMENT OF LOW-FREQUENCY DIELECTRIC NOISE

Using noncontact scanning probe microscopy techniques, dielectric prop erties were studied on 50-nm-length scales in poly-vinyl-acetate (PVAc ) and poly-methyl-methacrylate films. Low-frequency (1/f) fluctuations observed in the measurements, peaked in intensity near the glass tran sition temperature in PVAc. The noise is shown to arise from thermal d ielectric polarization fluctuations. Analysis of this noise provides a noninvasive method of probing equilibrium nanometer-scale dynamical p rocesses in dielectric materials and devices. (C) 1998 American Instit ute of Physics.