Positive and negative patterning on a palmitic acid Langmuir–Blodgett monolayer on Si surface using bias-dependent atomic force microscopy lithography

Abstract

It is well known that the anodization lithography using an atomic force microscope (AFM) can produce only a positive pattern under a tip negative bias. This study revealed that a negative pattern was generated due to the degradation of a resist under the positive bias. In order to maximize this polarity effect, a Langmuir–Blodgett monolayer of palmitic acid was used as a resist since the degraded molecules would be removed from the negatively biased substrate. This study enables the AFM lithography on a designed resist to generate a negative or positive pattern clearly by changing only one parameter, polarity of the bias. The complete degradation process was confirmed by lateral force microscopy.