The a-c domain boundary of a PZT thin film was measured. It was found that high resolution image of a-c boundary was obtained.
following is the PZT thin film image which is scanned at tiny area after polarization reversal voltage is applied. It turned out that the width of a c-c domain boundary is 1.87nm in the minimum, and it is said that resolution of SNDM is less than 1.87nm at a maximum.
PZT thin film, which is observed in smaller area, is exhibited here. It is said that a SNDM has a subnanometer order resolution.
The resolution of SNDM is depend on the linear dielectric constant.
For example, in case of ε=1000, the resolution of SNDM is about 0.01 times of the tip radius. This implies that if the electroconductive cantilever with tip radius is 10nm, the resolution of SNDM becomes 0.1nm.
And now, we are developing the SNDM technique with atomic resolution.
