Researchers develop low-cost transparent conducting film

The new coatings were developed as part of a programme to investigate low-cost, earth abundant materials and inexpensive deposition routes that could be used for large-area transparent conducting oxide coatings.

Transparent conducting oxides are used in a wide range of optoelectronic devices, including PV, LEDs and LCD touch screens. These materials are unique in that they can conduct electricity while being transparent to visible light. For optoelectronic devices to be able to emit or absorb light, it is important that the electrical contacts at the top of the device are optically transparent. Opaque metals and most transparent materials lack the balance between these two characteristics to be functional for use in such technology.

Currently, indium tin oxide (ITO) is used by more than 97 per cent of the transparent conducting oxide market as it possesses a near-ideal combination of high visible-light transparency and high electrical conductivity. However, indium metal is relatively scarce, expensive and has a highly volatile price. China produces more than half of the world’s indium and has recently significantly reduced its export quotas.