 |
03 Dec 2004
Transparent TFTs fabricated by Japanese scientists could accelerate the development of flexible displays.
Japanese scientists have found a way to fabricate flexible transparent thin-film transistors (TTFTs) at room temperature. The team believes its research could be useful for producing flexible displays and electronic devices such as electronic paper and wearable computers. (Nature 432 488)
Thin-film transistors are the building blocks for microelectronics such as flat-panel displays. The trouble is that producing flexible versions is very hard. The most popular based uses hydrogenated amorphous silicon (a-Si:H), but this does not perform to sufficient levels for use in flexible displays and computers.
"Fabricating high-performance devices is challenging owing to a trade-off between processing temperature and device performance," explains Hideo Hosono and his team from Toyko Institute of Technology. "We propose to solve this problem by using a transparent amorphous oxide semiconductor for the active channel in TTFTs."
The team used a material from the InGaZnO system called a-IGZO.
Hosono's flexible TTFTs are based on a 200 micron thick film of polyethylene terephthalate (PET). A 30 nm-thick active layer of a-IGZO sits on top of the PET followed by a 140 nm thick gate made from Y2O3 and a 40 nm thick ITO electrode.
The TTFT sheet was then bent to a radius of curvature of 30 mm. "The TTFT performance is almost unaffected by bending," say Hosono and colleagues. "After the initial bending, the TFT characteristics are stable and reproducible during and after bending."
"These achievements imply that transparent amorphous oxide semiconductors have the potential to overtake a-Si:H and a promising materials for transparent flexible electronics," concludes Hosono.
Author
Jacqueline Hewett is technology editor on Optics.org and Opto & Laser Europe magazine.
 |  |  |  |  |  |  |
| © 2024 SPIE Europe |
|
