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arXiv · 1501.00746

Tunnel field effect transistor on a quantum well formed by three layers of graphene derivatives (COH)n-(CF)n-(CH)n, with the drain from the middle layer - (CF)n

Abstract

In the paper the version of the field effect tunnel nano transistor on quantum well is researched, where the control voltage is applied to the barriers surrounding the quantum well, and electron drain comes from the quantum well. Electrons tunnel into the quantum well through the first half of the two-humped tunnel barrier (double heterojunction) formed by the sandwich of three layers of wide band 2D semiconductors (graphene derivatives: perhydrooxy grafen (COH)n, fluoro graphen (CF)n, grafan (CH)n) essentially differing in locations of the bottom level of the conduction band. The middle layer - fluoro graphen (CF)n has the lowest bottom of the conduction band, which forms the quantum well with depth of ~ 3 eV and a width of ~ 0.6 nm in the total tunnel potential barrier of 1.8 nm width, and serves as a channel for the flow of electrons. Metal electrode of source and metal electrode of gate adjacent to the outer layers of 2D semiconductor sandwich - perhydrooxy grafen (COH)n and grafan (CH)n, respectively, form the common "gate" of sandwich with size 22*22 nm^2. A metal drain electrode with a width of 10 nm and with the potential on 1 V higher than that of the first electrode (source) are in contact with the middle layer of fluoro graphen (CF)n, beyond of the sandwich having for this purpose the width of 35 nm greater than that of the outer semiconductor layers 2D internal three-layer sandwich. The potential of the gate opening is 0.62 V. The maximum operating current Isd is ~ 2*10^(-5) A. Current flowing in a closed state theoretically is equal to zero, and the parasitic current flowing through the gate electrode in the open state Ig = Ileak is ~ 10^(-10) A. Quantum capacitance of the transistor would allow the device to operate at a frequency of up to 10^12 Hz.

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Valery A. Zhukov, V. G. Maslov. 2015-01-05. Tunnel field effect transistor on a quantum well formed by three layers of graphene derivatives (COH)n-(CF)n-(CH)n, with the drain from the middle layer - (CF)n. https://arxiv.org/abs/1501.00746

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