Fabrication method for icoriented si singleelectron transistors

A new fabrication method for Si singleelectron transistors (SET's) is proposed. The method applies thermal oxidation to a Si wire with a fine trench across it on a silicononinsulator substrate. During the oxidation the Si wire with the fine trench is converted in a selforganized manner into a twin SET structure with two singleelectron islands one along each edge of the trench due to positiondependent oxidationrate modulation caused by stress accumulation. Test devices demonstrated at 40K that the twin SET structure can operate as two individual SET's. Since the present method produces two SET's at the same time in a tiny area it is suitable for integrating logic circuits based on passtransistortype logic and CMOStype logic which promises to lead to the fabrication of singleelectron logic LSI's.