FABRICATION AND CHARACTERIZATION OF QUANTUM-WIRE TRANSISTORS WITH SCHOTTKY INPLANE GATES FORMED BY AN IN-SITU ELECTROCHEMICAL PROCESS

Novel Schottky in-plane gate (IPG) quantum wire transistors were fabri cated for the first time, and their transport properties were investig ated. For fabrication of transistors, an AlGaAs/GaAs quantum well wire (QWW) was produced by etching, and platinum LPG electrodes were direc tly formed on both edges of the QWW by a new in situ electrochemical p rocess. The current-voltage (I-V) characteristics of the fabricated lo ng-channel and short-channel devices exhibited good field effect trans istor operation at 3-300 K. Simple theoretical models assuming either a constant mobility or a constant velocity were developed. They provid e a reasonably good phenomenological description of the observed I-V c haracteristics. Limitations of the models are also discussed. At low t emperatures, the short-channel device exhibited sharp quantized conduc tance steps in the units of 2e(2)/h near pinch-off, indicating one-dim ensional ballistic quantum transport. The first plateau of the conduct ance step remained visible up to 40 K, which is the highest reported s o far for the AlGaAs/GaAs system. (C) 1995 American Vacuum Society.