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Title: Negative charge trapping effects in Al{sub 2}O{sub 3} films grown by atomic layer deposition onto thermally oxidized 4H-SiC

Abstract

This letter reports on the negative charge trapping in Al{sub 2}O{sub 3} thin films grown by atomic layer deposition onto oxidized silicon carbide (4H-SiC). The films exhibited a permittivity of 8.4, a breakdown field of 9.2 MV/cm and small hysteresis under moderate bias cycles. However, severe electron trapping inside the Al{sub 2}O{sub 3} film (1 × 10{sup 12} cm{sup −2}) occurs upon high positive bias stress (>10 V). Capacitance-voltage measurements at different temperatures and stress conditions have been used to determine an activation energy of 0.1 eV. The results provide indications on the possible nature of the trapping defects and, hence, on the strategies to improve this technology for 4H-SiC devices.

Authors:
 [1];  [2]; ; ;  [1]
  1. Consiglio Nazionale delle Ricerche - Istituto per la Microelettronica e Microsistemi (CNR-IMM), Strada VIII 5, Zona industriale – 95121 Catania (Italy)
  2. (Italy)
Publication Date:
OSTI Identifier:
22611422
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Advances; Journal Volume: 6; Journal Issue: 7; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ACTIVATION ENERGY; ALUMINIUM OXIDES; BREAKDOWN; CAPACITANCE; DEFECTS; DEPOSITION; HYSTERESIS; LAYERS; PERMITTIVITY; SILICON; SILICON CARBIDES; STRESSES; THIN FILMS; TRAPPING

Citation Formats

Schilirò, Emanuela, E-mail: emanuela.schiliro@imm.cnr.it, Dipartimento di Scienze Chimiche, Università degli Studi di Catania, and INSTM udr Catania, viale Andrea Doria 6, 95125, Catania, Lo Nigro, Raffaella, Fiorenza, Patrick, and Roccaforte, Fabrizio. Negative charge trapping effects in Al{sub 2}O{sub 3} films grown by atomic layer deposition onto thermally oxidized 4H-SiC. United States: N. p., 2016. Web. doi:10.1063/1.4960213.
Schilirò, Emanuela, E-mail: emanuela.schiliro@imm.cnr.it, Dipartimento di Scienze Chimiche, Università degli Studi di Catania, and INSTM udr Catania, viale Andrea Doria 6, 95125, Catania, Lo Nigro, Raffaella, Fiorenza, Patrick, & Roccaforte, Fabrizio. Negative charge trapping effects in Al{sub 2}O{sub 3} films grown by atomic layer deposition onto thermally oxidized 4H-SiC. United States. doi:10.1063/1.4960213.
Schilirò, Emanuela, E-mail: emanuela.schiliro@imm.cnr.it, Dipartimento di Scienze Chimiche, Università degli Studi di Catania, and INSTM udr Catania, viale Andrea Doria 6, 95125, Catania, Lo Nigro, Raffaella, Fiorenza, Patrick, and Roccaforte, Fabrizio. 2016. "Negative charge trapping effects in Al{sub 2}O{sub 3} films grown by atomic layer deposition onto thermally oxidized 4H-SiC". United States. doi:10.1063/1.4960213.
@article{osti_22611422,
title = {Negative charge trapping effects in Al{sub 2}O{sub 3} films grown by atomic layer deposition onto thermally oxidized 4H-SiC},
author = {Schilirò, Emanuela, E-mail: emanuela.schiliro@imm.cnr.it and Dipartimento di Scienze Chimiche, Università degli Studi di Catania, and INSTM udr Catania, viale Andrea Doria 6, 95125, Catania and Lo Nigro, Raffaella and Fiorenza, Patrick and Roccaforte, Fabrizio},
abstractNote = {This letter reports on the negative charge trapping in Al{sub 2}O{sub 3} thin films grown by atomic layer deposition onto oxidized silicon carbide (4H-SiC). The films exhibited a permittivity of 8.4, a breakdown field of 9.2 MV/cm and small hysteresis under moderate bias cycles. However, severe electron trapping inside the Al{sub 2}O{sub 3} film (1 × 10{sup 12} cm{sup −2}) occurs upon high positive bias stress (>10 V). Capacitance-voltage measurements at different temperatures and stress conditions have been used to determine an activation energy of 0.1 eV. The results provide indications on the possible nature of the trapping defects and, hence, on the strategies to improve this technology for 4H-SiC devices.},
doi = {10.1063/1.4960213},
journal = {AIP Advances},
number = 7,
volume = 6,
place = {United States},
year = 2016,
month = 7
}
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