Height (a) and phase (a') images of the blended film. Taken with a softer tip cantilever with a spring constant of 3 N/m at A0 = 60 nm and rsp = 0.5. The scanning size is 500 nm × 500 nm.
Li et al. Nanoscale Research Letters 2012 7:153 doi:10.1186/1556-276X-7-153