Coulomb Blockade Effects in Edge Quantum Wire SOI MOSFETs

Abstract

Edge quantum wire MOSFETs were fabricated using the sidewall of an ultrathin SOI, and the electrical characteristics were investigated. In this device, current oscillations for gate voltage sweeping were clearly observed at 4.2 K. This effect is considered from the viewpoint of the Coulomb oscillations in the multijunction system on the edge quantum wire. Furthermore, we focus on two concerns regarding the application of the single electron tunneling (SET) devices. One concern is the phase instability of the Coulomb oscillations due to trapped or floating charges around the SET devices. To overcome this problem, we propose a double-gate edge SOI MOSFET. In fact, it is experimentally confirmed that the Coulomb oscillation phase is tunable. The other concern is the low driving capability of SET devices. To improve this, it has also been experimentally demonstrated that the direct transmission of SET signals to the conventional MOSFET current is possible. This means that the output impedance can be transformed locally or globally from high to low in the SET-device circuits hybridized with CMOS devices.