KINETICS OF ELECTRON CHARGING AND DISCHARGING ON EMBEDDED W-DISKS IN GAAS

Electron-capture and -emission processes in nanometer-sized Schottky c ontacts on a floating potential have been studied experimentally. Arra nged patterns of tungsten disks have been embedded in GaAs by epitaxia l overgrowth and a buried semi-insulating layer is created by overlapp ing depletion regions from the individual disks. We have investigated the embedded metal-semiconductor contacts by space-charge techniques. We demonstrate how these buried contacts can be characterized opticall y and electrically, and that the metal disks may be charged and discha rged in a controlled way. The data reveal the difference between singl e- and multiple-electron processes.