Skip to Content
Find More Like This
Return to Search

High Quality Transparent Conducting Oxide Thin Films

National Renewable Energy Laboratory

Contact NREL About This Technology

Technology Marketing Summary

Transparent conducting oxides (TCO) are thin films that are both electrically conductive and optically transparent, and therefore used in a wide variety of devices including flat-panel displays and photovoltaic systems. Zinc oxide (ZnO) films, specifically, are commonly used due to the abundance and low toxicity of zinc. Despite their wide adoption, there are problems with these TCOs. Electron mobility, a measure of how quickly charge carriers can move through a conductor, is an important consideration for photovoltaic systems and a limitation of current ZnO TCOs. A ZnO film that allows higher electron mobility while maintaining high current density (these two parameters determine overall conductivity) could enable the creation of more efficient photovoltaic systems.


Researchers at NREL have created a ZnO film doped with Group 5A materials that exhibits both a high electron mobility of 42 cm2/(V·s) while simultaneously maintaining a high carrier concentration of 4.4×1020 cm-3. The TCO also demonstrates optical transparency and a greater resistance to chemical corrosion than current ZnO films. The invention will allow high reliability at high throughput by utilizing deposition attributes consistent with current industrial production processes such as radio-frequency controlled magnetron sputtering, press-powder ceramic targets, and a sputter ambient in which the hydrogen partial pressure is controlled carefully.

  • Increased electron mobility
  • High optical transparency
  • Resistance to chemical corrosion
  • Compatible with current production processes
Applications and Industries
  • Photovoltaics
  • Flat-panel displays
  • Touchscreens
Patents and Patent Applications
ID Number
Title and Abstract
Primary Lab
Patent 8,253,012
High quality transparent conducting oxide thin films
A transparent conducting oxide (TCO) film comprising: a TCO layer, and dopants selected from the elements consisting of Vanadium, Molybdenum, Tantalum, Niobium, Antimony, Titanium, Zirconium, and Hafnium, wherein the elements are n-type dopants; and wherein the transparent conducting oxide is characterized by an improved electron mobility of about 42 cm.sup.2/V-sec while simultaneously maintaining a high carrier density of .about.4.4e.times.10.sup.20 cm.sup.-3.
National Renewable Energy Laboratory 08/28/2012
Technology Status
Technology IDDevelopment StageAvailabilityPublishedLast Updated
NREL ROI 07-42PrototypeAvailable09/07/201709/07/2017

Contact NREL About This Technology

To: Bill Hadley<>