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Title: Can p-channel tunnel field-effect transistors perform as good as n-channel?

We show that bulk semiconductor materials do not allow perfectly complementary p- and n-channel tunnel field-effect transistors (TFETs), due to the presence of a heavy-hole band. When tunneling in p-TFETs is oriented towards the gate-dielectric, field-induced quantum confinement results in a highest-energy subband which is heavy-hole like. In direct-bandgap IIIV materials, the most promising TFET materials, phonon-assisted tunneling to this subband degrades the subthreshold swing and leads to at least 10× smaller on-current than the desired ballistic on-current. This is demonstrated with quantum-mechanical predictions for p-TFETs with tunneling orthogonal to the gate, made out of InP, In{sub 0.53}Ga{sub 0.47}As, InAs, and a modified version of In{sub 0.53}Ga{sub 0.47}As with an artificially increased conduction-band density-of-states. We further show that even if the phonon-assisted current would be negligible, the build-up of a heavy-hole-based inversion layer prevents efficient ballistic tunneling, especially at low supply voltages. For p-TFET, a strongly confined n-i-p or n-p-i-p configuration is therefore recommended, as well as a tensily strained line-tunneling configuration.
Authors:
; ; ;  [1] ; ; ;  [1] ;  [2] ;  [1] ;  [2]
  1. Imec, Kapeldreef 75, 3001 Leuven (Belgium)
  2. (Belgium)
Publication Date:
OSTI Identifier:
22311215
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 4; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CONFIGURATION; CONFINEMENT; CURRENTS; DENSITY; DIELECTRIC MATERIALS; ELECTRIC POTENTIAL; FIELD EFFECT TRANSISTORS; FORECASTING; INDIUM ARSENIDES; INDIUM PHOSPHIDES; LAYERS; PHONONS; QUANTUM MECHANICS; SEMICONDUCTOR MATERIALS; STRAINS; TUNNEL EFFECT