Room temperature operated single electron transistor made by a scanning tunnelling microscopy/atomic force microscopy nano-oxidation process

Application of scanning tunnelling microscopy (STM) and atomic force microscopy (AFM) to an electron device is introduced in this paper. Using a STM tip/AFM cantilever as a cathode, the surface of a metal is oxidized to form a few tens of nanometre wide oxidized metal line, which works as an energy barrier for an electron. A single electron transistor (SET) is fabricated using this fabrication process. As a STM/AFM, nano-oxidation process could fabricate the device size of the order of 10 nm, the fabricated SET operates even at a higher temperature than room temperature and shows the large Coulomb gap and staircase of 200 mV periods. An atomically Aat alpha-Al2O3 substrate is proposed for improving the uniformity and reproducibility of the oxidized line made by a STM/AFM nano-oxidation process.