2008-09-19
Research from the van Dover group:
Researchers in the van Dover group are using a combinatorial technique of depositing thin film materials to study transparent conducting oxide (TCO) materials. An example of a TCO is indium tin oxide which is used in flat panel displays and photovoltaics. However, research into zinc oxide (ZnO), a replacement TCO, has shown a lot of promise due to the low cost and low toxicity of ZnO. The van Dover group is currently using the combinatorial technique to improve the electrical properties of ZnO.
The combinatorial technique uses co-sputtering with two or three off axis sputtering guns to deposit a film that has a large range of composition across a single 2-3 inch substrate. For example, on a single sample, the composition of two ZnO dopants such as (aluminum and indium) can vary from 1% to 7% each. Analyzing the substrate using a variety of high throughput techniques such as x-ray diffraction to elucidate the atomic structure and 4-point probe to measure conductivity, the van Dover group has demonstrated that co-doping with both aluminum and indium improves the electrical properties of ZnO in comparison to ZnO doped with either aluminum or indium alone.