Subthreshold voltage-induced transferred charge measurements of evaporated ZnS:Mn alternating-current thin-film electroluminescent devices

TitleSubthreshold voltage-induced transferred charge measurements of evaporated ZnS:Mn alternating-current thin-film electroluminescent devices
Publication TypeJournal Article
Year of Publication2002
AuthorsCleary, B. A., P. D. Keir, J. C. Hitt, T. K. Plant, J. F. Wager, B. Aitchison, R. T. Tuenge, and S. S. Sun
JournalJournal of the Society for Information Display
Volume10
Issue3
Pagination271
Date Published09/2002
ISSN10710922
Keywordselectro-optic characterization, electroluminescence, ZnS
Abstract

Subthreshold voltage-induced transferred charge (VIQ) analysis is proposed as a novel method for assessing the nature of aging in alternating-current thin-film electroluminescent (ACTFEL) devices. VIQ analysis involves the application of 20,000 bipolar voltage pulses of variable amplitude and measurement of the subthreshold charge transferred in the phosphor for voltage amplitudes from 0 V to threshold. VIQ experiments provide information related to the physical location, density, energy depth, and capture cross-section of phosphor traps responsible for ACTFEL device aging. VIQ aging experiments were performed on ZnS:Mn ACTFEL devices whose phosphor layers were deposited by thermal evaporation, atomic layer epitaxy using chlorine as a constituent of the precursor gas [ALE (Cl)], and atomic layer epitaxy with diethyl zinc as a precursor gas [ALE (DEZ)]. The depth of the traps responsible for VIQ in evaporated, ALE (Cl), and ALE (DEZ) ZnS:Mn are estimated to be ~1.0–1.2, ~0.3, and ~0.7–0.9 eV, respectively. It is speculated that the traps responsible for VIQ are due to sulfur vacancies, chlorine, and oxygen, for evaporated, ALE (Cl), and ALE (DEZ), respectively.

DOI10.1889/1.1827879
Short TitleJ. Soc. Inf. Display