March 20, 2006 – Researchers at Oregon State U. have developed a completely transparent IC from inorganic compounds, which by the end of this decade could replace organic or polymer materials in applications such as solar cells or liquid crystal displays.
The IC, a five-stage “ring oscillator” commonly used in electronics for testing and new technology demonstrations, is based on indium gallium oxide (OSU’s earlier efforts focused on zinc-tin-oxide). Both compounds offer high electron mobility, chemical stability, physical durability, and ease of manufacture at low temperatures, the researchers noted, and are relatively cheap and environmentally friendly vs. alternative heavy metals such as gold and silver, mercury, lead, or arsenic.
The research has been supported by the National Science Foundation, Army Research Office, and HP, which has licensed the rights to market new products based on the technology, providing a partner to help scale and commercialize it. Potential uses range from transparent displays in cars to cell phones, televisions, copiers, and “smart” glass, as well as more efficient solar cells and LCDs.
In a statement, John Wager, prof. of electrical engineering at OSU, noted that several difficult milestones need to be addressed and overcome, including scaling the technology to larger sizes, making all process steps manufacturing-ready, and finding ways to physically protect the new circuits, as well as identify specific new markets and products. Work will continue toward a “P-channel” device that would offer lower power consumption, simple electronic architecture, and ability to do both analog and digital processing.
“What’s exciting is that all of the remaining work seems very feasible,” Wager said. “It will take some time, but we just don’t see any major obstacles that are going to preclude the commercial use of transparent electronics with these compounds.”
The project is affiliated with the Oregon Nanoscience and Microtechnologies Institute, an R&D collaboration involving Oregon’s three public research universities: OSU, Portland State U., and the U. of Oregon, as well as other regional labs and state and business support.