Modeling direct band-to-band tunneling: From bulk to quantum-confined semiconductor devices

Journal Article · Sun Jun 21 00:00:00 EDT 2015 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4922427· OSTI ID:22412947

Carrillo-Nuñez, H.; Ziegler, A.; Luisier, M.; Schenk, A. ^[1]

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1. Integrated Systems Laboratory ETH Zürich, Gloriastrasse 35, 8092 Zürich (Switzerland)

A rigorous framework to study direct band-to-band tunneling (BTBT) in homo- and hetero-junction semiconductor nanodevices is introduced. An interaction Hamiltonian coupling conduction and valence bands (CVBs) is derived using a multiband envelope method. A general form of the BTBT probability is then obtained from the linear response to the “CVBs interaction” that drives the system out of equilibrium. Simple expressions in terms of the one-electron spectral function are developed to compute the BTBT current in two- and three-dimensional semiconductor structures. Additionally, a two-band envelope equation based on the Flietner model of imaginary dispersion is proposed for the same purpose. In order to characterize their accuracy and differences, both approaches are compared with full-band, atomistic quantum transport simulations of Ge, InAs, and InAs-Si Esaki diodes. As another numerical application, the BTBT current in InAs-Si nanowire tunnel field-effect transistors is computed. It is found that both approaches agree with high accuracy. The first one is considerably easier to conceive and could be implemented straightforwardly in existing quantum transport tools based on the effective mass approximation to account for BTBT in nanodevices.

• OSTI ID: 22412947
• Journal Information: Journal of Applied Physics, Vol. 117, Issue 23; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
APPROXIMATIONS
COMPARATIVE EVALUATIONS
COUPLING
EFFECTIVE MASS
ELECTRIC CONTACTS
ELECTRONIC STRUCTURE
FIELD EFFECT TRANSISTORS
GERMANIUM
HAMILTONIANS
INDIUM ARSENIDES
SEMICONDUCTOR JUNCTIONS
SEMICONDUCTOR MATERIALS
SILICON
THREE-DIMENSIONAL LATTICES
TUNNEL EFFECT
VALENCE