Abstract

This investigation elucidates the influence of standalone-bias stress and standalone-illumination stress, and their combinatory effect on indium-gallium-zinc oxide (IGZO) thin-film transistors (TFTs). Each phenomenon associated with illumination (wavelengths of 410, 467, 532 and 632 nm) and bias (Vg = ±20 V; Vd = 0, 20 V) stresses is categorized individually. Wavelengths below 532 nm are responsible for ionized vacancy creation, carrier generation and interface state creation while only gate stresses of +20 V create excessive charge trap states. Failure conditions are identified as gate stresses of -20 V with 410 nm illumination. An improvement in the Ion/Ioff ratio from 106 to 107 is due to increased charge contribution for on currents, and trapping of holes at the intermetallic dielectric near the source-channel junction in the off region. Upon stress removal TFTs exhibit incomplete recovery due to slow trapping of excited carriers from dielectric layers and inability created by the passivation layer to absorb oxygen for vacancy regeneration. The low-temperature fabrication and optimized post-fabrication anneal have created reduced defect and vacancy densities that make the IGZO TFTs more stable than the previous generation TFTs.

Original languageEnglish (US)
Article number045101
JournalJournal of Physics D: Applied Physics
Volume46
Issue number4
DOIs
StatePublished - Jan 30 2013

Fingerprint

Zinc Oxide
gallium oxides
Gallium
Indium
Thin film transistors
Zinc oxide
zinc oxides
Oxide films
indium
transistors
Lighting
illumination
Defects
defects
thin films
Vacancies
trapping
Fabrication
Wavelength
fabrication

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Electronic, Optical and Magnetic Materials
  • Acoustics and Ultrasonics
  • Surfaces, Coatings and Films

Cite this

Investigation of defect generation and annihilation in IGZO TFTs during practical stress conditions : Illumination and electrical bias. / Vemuri, Rajitha N P; Mathews, Winnie P.; Marrs, Michael; Alford, Terry.

In: Journal of Physics D: Applied Physics, Vol. 46, No. 4, 045101, 30.01.2013.

Research output: Contribution to journalArticle

@article{d8a3ef6943ef4a67ab71444355c910bd,
title = "Investigation of defect generation and annihilation in IGZO TFTs during practical stress conditions: Illumination and electrical bias",
abstract = "This investigation elucidates the influence of standalone-bias stress and standalone-illumination stress, and their combinatory effect on indium-gallium-zinc oxide (IGZO) thin-film transistors (TFTs). Each phenomenon associated with illumination (wavelengths of 410, 467, 532 and 632 nm) and bias (Vg = ±20 V; Vd = 0, 20 V) stresses is categorized individually. Wavelengths below 532 nm are responsible for ionized vacancy creation, carrier generation and interface state creation while only gate stresses of +20 V create excessive charge trap states. Failure conditions are identified as gate stresses of -20 V with 410 nm illumination. An improvement in the Ion/Ioff ratio from 106 to 107 is due to increased charge contribution for on currents, and trapping of holes at the intermetallic dielectric near the source-channel junction in the off region. Upon stress removal TFTs exhibit incomplete recovery due to slow trapping of excited carriers from dielectric layers and inability created by the passivation layer to absorb oxygen for vacancy regeneration. The low-temperature fabrication and optimized post-fabrication anneal have created reduced defect and vacancy densities that make the IGZO TFTs more stable than the previous generation TFTs.",
author = "Vemuri, {Rajitha N P} and Mathews, {Winnie P.} and Michael Marrs and Terry Alford",
year = "2013",
month = "1",
day = "30",
doi = "10.1088/0022-3727/46/4/045101",
language = "English (US)",
volume = "46",
journal = "Journal Physics D: Applied Physics",
issn = "0022-3727",
publisher = "IOP Publishing Ltd.",
number = "4",

}

TY - JOUR

T1 - Investigation of defect generation and annihilation in IGZO TFTs during practical stress conditions

T2 - Illumination and electrical bias

AU - Vemuri, Rajitha N P

AU - Mathews, Winnie P.

AU - Marrs, Michael

AU - Alford, Terry

PY - 2013/1/30

Y1 - 2013/1/30

N2 - This investigation elucidates the influence of standalone-bias stress and standalone-illumination stress, and their combinatory effect on indium-gallium-zinc oxide (IGZO) thin-film transistors (TFTs). Each phenomenon associated with illumination (wavelengths of 410, 467, 532 and 632 nm) and bias (Vg = ±20 V; Vd = 0, 20 V) stresses is categorized individually. Wavelengths below 532 nm are responsible for ionized vacancy creation, carrier generation and interface state creation while only gate stresses of +20 V create excessive charge trap states. Failure conditions are identified as gate stresses of -20 V with 410 nm illumination. An improvement in the Ion/Ioff ratio from 106 to 107 is due to increased charge contribution for on currents, and trapping of holes at the intermetallic dielectric near the source-channel junction in the off region. Upon stress removal TFTs exhibit incomplete recovery due to slow trapping of excited carriers from dielectric layers and inability created by the passivation layer to absorb oxygen for vacancy regeneration. The low-temperature fabrication and optimized post-fabrication anneal have created reduced defect and vacancy densities that make the IGZO TFTs more stable than the previous generation TFTs.

AB - This investigation elucidates the influence of standalone-bias stress and standalone-illumination stress, and their combinatory effect on indium-gallium-zinc oxide (IGZO) thin-film transistors (TFTs). Each phenomenon associated with illumination (wavelengths of 410, 467, 532 and 632 nm) and bias (Vg = ±20 V; Vd = 0, 20 V) stresses is categorized individually. Wavelengths below 532 nm are responsible for ionized vacancy creation, carrier generation and interface state creation while only gate stresses of +20 V create excessive charge trap states. Failure conditions are identified as gate stresses of -20 V with 410 nm illumination. An improvement in the Ion/Ioff ratio from 106 to 107 is due to increased charge contribution for on currents, and trapping of holes at the intermetallic dielectric near the source-channel junction in the off region. Upon stress removal TFTs exhibit incomplete recovery due to slow trapping of excited carriers from dielectric layers and inability created by the passivation layer to absorb oxygen for vacancy regeneration. The low-temperature fabrication and optimized post-fabrication anneal have created reduced defect and vacancy densities that make the IGZO TFTs more stable than the previous generation TFTs.

UR - http://www.scopus.com/inward/record.url?scp=84872400984&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84872400984&partnerID=8YFLogxK

U2 - 10.1088/0022-3727/46/4/045101

DO - 10.1088/0022-3727/46/4/045101

M3 - Article

AN - SCOPUS:84872400984

VL - 46

JO - Journal Physics D: Applied Physics

JF - Journal Physics D: Applied Physics

SN - 0022-3727

IS - 4

M1 - 045101

ER -