Principle of Nanolithography with SPM

SPM is widely used as research tool and industrial measuring instrument, and has drawn attraction as nanoscale processing tool at nanometer order from the initial stage of development. The atomic operation became possible by SPM [54], and scanning probe nanolithography (SPNL) was developed at ca. 10 nm level [55]. There are three major categories for SPNL as follows  

The method nearest to electronic device fabrication is the nanoscale processing based on the anodic oxidation of semiconductors and metals. The following electrochemical reactions proceed after applying voltage between the probe and the substrate in the column of adsorbed water generated at the region between them in the air as shown in Fig. 17. 

The oxide film of the substrate is formed at the front of the probe. It is, therefore, possible to form patterns to scan the probe. 

Other processing techniques, such as etching and metal plating, are also necessary to be developed when the nanopattern drawing by SPM is advanced 

The organic thin films used in lithography are polymer casting films, Langmuir-Blodgett (LB) films, SAMs and plasma-polymerized films. The molecular designs and syntheses of organic monolayer materials are studied for SPNL resists [89]. 

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