TOKYO -- Toshiba Corporation today announced the world's first 12.1-inch TFT liquid crystal display utilizing low-temperature polysilicon technology. This next-generation technology increases display reliability by cutting the number of peripheral components, and has the potential to realize higher levels of resolution for display panels. Toshiba's new display, which achieves XGA-level high resolution of 1,024 x 768 pixels, demonstrates for the first time the commercial viability of large-size polysilicon TFT LCDs.

The advantages offered by low-temperature polysilicon is expected to establish it as a mainstream display technology for displays for computers and other information equipment. As driver LCDs can be formed directly on the LCD substrate, the overall component count can be reduced to as much as 40% that of a typical amorphous silicon TFT LCD, and the number of connection pins can be reduced to 1/20th, contributing to product reliability. Polysilicon technology also supports higher resolution levels, in line with the trend in the industry, and does so without the physical limitations imposed on LCDs requiring peripheral driver circuits.

Toshiba also announced that it will construct a mass-production line for large-size polysilicon TFT LCDs at its Fukaya Display Devices Works in Saitama Prefecture, north of Tokyo. Construction of a new clean room for the mass production line will begin next month, with production slated to start by the end of 1998.

Fukaya Works is the obvious site for the new mass-production line. It is home to Toshiba's LCD Research & Development Center, established in April 1997, and also has a prototyping and production line for low-temperature polysilicon displays, which has been used to develop manufacturing technology for polysilicon TFT LCDs since July this year. The proximity of these operations will facilitate transfer of the technological and manufacturing know-how to the new line.

Low-temperature polysilicon TFT LCD
The substrate is composed of polycrystal silicon, which obtains much higher electron mobility than the amorphous silicon found in active matrix and other LCDs. Polycrystal silicon allows each pixel cell to be more easily controlled by smaller peripheral circuits, including driver ICs. This makes it possible to bring the peripheral driver circuits that control the LCD display directly onto the substrate, with no need for external mounting around the display panel, thus reducing the overall component count and the number of connection pins required.

Major Specifications of 12.1" XGA Low-temp Polysilicon TFT LCD