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Title: Near interface traps in SiO{sub 2}/4H-SiC metal-oxide-semiconductor field effect transistors monitored by temperature dependent gate current transient measurements

Abstract

This letter reports on the impact of gate oxide trapping states on the conduction mechanisms in SiO{sub 2}/4H-SiC metal-oxide-semiconductor field effect transistors (MOSFETs). The phenomena were studied by gate current transient measurements, performed on n-channel MOSFETs operated in “gate-controlled-diode” configuration. The measurements revealed an anomalous non-steady conduction under negative bias (V{sub G} > |20 V|) through the SiO{sub 2}/4H-SiC interface. The phenomenon was explained by the coexistence of a electron variable range hopping and a hole Fowler-Nordheim (FN) tunnelling. A semi-empirical modified FN model with a time-depended electric field is used to estimate the near interface traps in the gate oxide (N{sub trap} ∼ 2 × 10{sup 11} cm{sup −2}).

Authors:
; ; ;  [1]
  1. Consiglio Nazionale delle Ricerche-Istituto per la Microelettronica e Microsistemi (CNR-IMM), Strada VIII 5, Zona Industriale 95121 Catania (Italy)
Publication Date:
OSTI Identifier:
22590578
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 1; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CURRENTS; ELECTRIC FIELDS; INTERFACES; MOSFET; SEMICONDUCTOR MATERIALS; SILICON CARBIDES; SILICON OXIDES; TEMPERATURE DEPENDENCE; TRANSIENTS; TUNNEL EFFECT

Citation Formats

Fiorenza, Patrick, La Magna, Antonino, Vivona, Marilena, and Roccaforte, Fabrizio. Near interface traps in SiO{sub 2}/4H-SiC metal-oxide-semiconductor field effect transistors monitored by temperature dependent gate current transient measurements. United States: N. p., 2016. Web. doi:10.1063/1.4955465.
Fiorenza, Patrick, La Magna, Antonino, Vivona, Marilena, & Roccaforte, Fabrizio. Near interface traps in SiO{sub 2}/4H-SiC metal-oxide-semiconductor field effect transistors monitored by temperature dependent gate current transient measurements. United States. doi:10.1063/1.4955465.
Fiorenza, Patrick, La Magna, Antonino, Vivona, Marilena, and Roccaforte, Fabrizio. 2016. "Near interface traps in SiO{sub 2}/4H-SiC metal-oxide-semiconductor field effect transistors monitored by temperature dependent gate current transient measurements". United States. doi:10.1063/1.4955465.
@article{osti_22590578,
title = {Near interface traps in SiO{sub 2}/4H-SiC metal-oxide-semiconductor field effect transistors monitored by temperature dependent gate current transient measurements},
author = {Fiorenza, Patrick and La Magna, Antonino and Vivona, Marilena and Roccaforte, Fabrizio},
abstractNote = {This letter reports on the impact of gate oxide trapping states on the conduction mechanisms in SiO{sub 2}/4H-SiC metal-oxide-semiconductor field effect transistors (MOSFETs). The phenomena were studied by gate current transient measurements, performed on n-channel MOSFETs operated in “gate-controlled-diode” configuration. The measurements revealed an anomalous non-steady conduction under negative bias (V{sub G} > |20 V|) through the SiO{sub 2}/4H-SiC interface. The phenomenon was explained by the coexistence of a electron variable range hopping and a hole Fowler-Nordheim (FN) tunnelling. A semi-empirical modified FN model with a time-depended electric field is used to estimate the near interface traps in the gate oxide (N{sub trap} ∼ 2 × 10{sup 11} cm{sup −2}).},
doi = {10.1063/1.4955465},
journal = {Applied Physics Letters},
number = 1,
volume = 109,
place = {United States},
year = 2016,
month = 7
}
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