Electron wave-packet transport through nanoscale semiconductor device in time domain

• Future low-power downscaled metal-oxide-semiconductor (MOS) devices are in a size regime that requires a quantum-mechanical approach. Two theoretical approaches, the steady-state single plane-wave transport model and the time-dependent wave-packet transport model, have been discussed to study the electron transport through model nanoscale potential profiles. It has been shown that the single plane-wave transport model at steady state neglects the coupling among different plane waves induced by the potential profile variation induced by the external bias. Thus, the model is only valid when the external bias is rather small. The electron wave-packet transport theory models the electrons by wave packets consisting of all available plane waves in the contact from where the electrons originate. The couplings among different plane waves are included in the temporal evolution of the time-dependent Schrodinger equation. This model is thus more proper when studying nanoscale devices at normal device working configurations. The effects of gate bias and the device geometry on the wave-packet transport are then studied by model potentials of future downscaled devices, which explains the experimentally reported conventional I-V characteristics of nanoscale MOS field-effect transistors (MOSFETs) at room temperature, while the normal MOSFET functioning is expected to be impossible by the single plane-wave transport model due to the independent tunneling effects of individual plane waves.

Subject headings

NATURVETENSKAP  -- Fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences (hsv//eng)

Keyword

TECHNOLOGY

TEKNIKVETENSKAP

Publication and Content Type

ref (subject category)

art (subject category)