Sharp Corp. is starting volume production this month of system LCD products that integrate logic into display panels at a facility in Tenri, Japan, that has seen an investment of 46 billion ($370 million) since August last year.
The plant can produce 2.5 million 2-inch equivalent displays a month. But according to Staffan Kordina, LCD product marketing manager at Sharp in Europe, this will only meet the demands of two major customers, so another facility is being built at Mie, Japan.
This will cost another 50 billion ($402 million) and be capable of producing four million 2-inch-equivalent LCDs per month when it opens in October next year. The Tenri facility will be capable of handling mother glass sizes of 620 x 750 mm while Mie facility will handle 730 x 920-mm panels.
System LCDs have IC circuitry built into the display panel, and use a continuous grain silicon (CGS) technology that was developed by Sharp in collaboration with the Japanese Semiconductor Energy Laboratories. CGS uses a thin layer of bonded silicon crystals on a glass substrate, and will enable large displays to be made.
The design allows processors and graphics chips to be built directly on to the glass substrate together with the crystals, an integration that's not possible with amorphous silicon.
In the Sharp substrate, there is a steady transition between the individual polysilicon crystals. Electronics in the CGS layer move around 600 times faster than in amorphous silicon crystals.
The technology will enable ultrathin mini displays to be built into chip cards, Sharp said. This could lead to video phones the size of a credit card, the company said. Replacement of the glass with plastic could produce a flexible LCD.