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Title: Amorphous transparent conducting oxides in context: Work function survey, trends, and facile modification

Journal Article · · Applied Surface Science
 [1];  [2];  [2];  [3];  [2];  [2]
  1. Northwestern Univ., Evanston, IL (United States); Argonne National Lab. (ANL), Argonne, IL (United States)
  2. Northwestern Univ., Evanston, IL (United States)
  3. Argonne National Lab. (ANL), Argonne, IL (United States)
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We report the work functions of various amorphous and crystalline transparent conducting oxides (TCOs) were measured using Kelvin probe. The films, made by pulsed laser deposition, exhibited varying work functions dependent on the composition and deposition parameters. Tin oxide showed the largest work functions of the oxides measured, while zinc oxide showed the lowest. Binary and ternary combinations of the basis TCOs showed intermediate work functions dependent on the endpoint components. Amorphous TCOs, important in OPV and other technological applications, exhibited similar work functions to their crystalline counterparts. UV/ozone treatment of TCOs temporarily increased the work function, consistent with proposed defect mechanisms associated with near-surface changes in carrier content and Fermi level. Finally, a method for facile adjustment of the work function of commercial TCOs by atomic layer deposition (ALD) capping layers was presented, illustrated by the growth of zinc oxide layers on commercial crystalline ITO films.

Research Organization:
Energy Frontier Research Centers (EFRC) (United States). Argonne-Northwestern Solar Energy Research Center (ANSER) (ANSER)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES)
Grant/Contract Number:
SC0001059
OSTI ID:
1384732
Alternate ID(s):
OSTI ID: 1247213
Journal Information:
Applied Surface Science, Vol. 330, Issue C; Related Information: ANSER partners with Northwestern University (lead); Argonne National Laboratory; University of Chicago; University of Illinois, Urbana-Champaign; Yale University; ISSN 0169-4332
Publisher:
ElsevierCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 35 works
Citation information provided by
Web of Science

References (22)

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Cited By (4)

Transparent Electrodes for Efficient Optoelectronics journal March 2017
Recent Advances in Understanding the Structure and Properties of Amorphous Oxide Semiconductors journal August 2017
On the use of a charged tunnel layer as a hole collector to improve the efficiency of amorphous silicon thin-film solar cells journal June 2015
Suitability of Various Materials for Probes in Scanning Kelvin Probe Measurements journal December 2017

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Related Subjects

36 MATERIALS SCIENCE
Work function
Transparent conducting oxides
Amorphous
TCO
Kelvin probe
Catalysis (homogeneous)
Catalysis (heterogeneous)
Solar (photovoltaic)
Solar (fuels)
Photosynthesis (natural and artificial)
Bio-inspired
Hydrogen and fuel cells
Electrodes - solar
Defects
Charge transport
Spin dynamics
Membrane
Materials and chemistry by design
Optics
Synthesis (novel materials)
Synthesis (self-assembly)