IEEE Transactions on Electron Devices, Vol. 47, No. 1, pp. 113-120, January 2000.

(Manuscript received September 8, 1998; revised May 4, 1999.)

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The novel characteristics of a new type of MOSFET, the hetero-material gate field-effect transistor (HMGFET), are explored theoretically and compared with those of the compatible MOSFET.  Two conceptual processes for realizing the HMG structure are proposed for integration into the existing silicon technology.  The 2-D numerical simulations reveal that the HMGFET demonstrates extended threshold voltage roll-off to much smaller length and shows simultaneous transconductance enhancement and suppression of short-channel effects (drain-induced barrier-lowering and channel-length modulation) and, more importantly, these unique features could be controlled by engineering the material and length of the gate.  This work demonstrates a new way of engineering ultra-small transistors and provides the incentive and guide for experimental exploration.

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