Ambipolar coulomb blockade characteristics in a two-dimensional si multidot device

This article presented a new fabrication method of Si SET devices with a 2-D multidot channel and study their electrical characteristics. The multidots are formed using a nanometerscale local oxidation of Si (nano-LOCOS) process developed by the authors. A two-dimensional Si multidot channel field-effect transistor is fabricated from a silicon-on-insulator material and the electrical characteristics are studied. The multidots are formed using a nanometer-scale local oxidation of Si process developed in our laboratory. The device shows ambipolar characteristics because of Schottky source and drain, i.e., the carriers are electrons for positive gate voltage and holes for the negative one. It is shown that Coulomb blockade (CB) oscillations are clearly observed for both of the electrons and holes at measurement temperatures up to 60 K.Both CB characteristics show nonperiodic oscillation and an open Coulomb diamond. These features are ascribed to the single electron/hole tunneling in the Si multidot channel. It presented the fabrication method and carrier transport characteristics of a 2-D Si multidot SET device in SOI substrate. The multidots are formed by using nano-LOCOS process developed by the authors. It was demonstrated that our device has ambipolar CB characteristics, in which the single-electron and single-hole transport phenomena were clearly observed at temperatures up to 60 K. In both CB characteristics, the spacing between the current peaks in the CB oscillations is not constant and the rhombus-shaped structures in the current contour plot for Vds-Vbg show open diamond. These features are associated with the electron/hole transport through Si multidot structure. Moreover, it was confirmed that the single-charge transport are induced from the geometrical structures of the dots, indicating that the characteristics can be tuned up by nano-LOCOS process.(EMS2022)