By Chris Chinnock
ETOBICOKE, Ontario - Last fall, leaders of Image Quest Technologies in Fremont, Calif., closed the doors on their fabrication facility for liquid crystal displays (LCDs), leaving Optical Imaging Systems in Northville, Mich., dpiX in Palo Alto, Calif., and Litton Systems Canada in Etobicoke, Ontario, as the last remaining North American suppliers of active-matrix LCD glass.
That number has now dwindled to two, as executives of Litton Systems Canada recently confirmed they had shut down operations on their 15,000-square-foot production facility. Company scientists will continue some limited research and development, but officials have reassigned all of the production personnel.
The facility could soon reemerge in a new suit of clothes with a new buyer, however. "We are now negotiating with three bidders for the facility that want to use it to make solid-state X-ray detector modules, Litton`s John Wright says. "We anticipate new investment in the manufacturing operation and a reassignment of key personnel through this venture."
Litton Systems Canada`s main focus of development was on active-matrix displays using a CdSe material, instead of the more popular amorphous silicon, to fabricate the on-screen transistors. In fact, CdSe was the first material that Westinghouse designers used to make active-matrix displays back in the 1960s.
In 1986, Litton executives purchased Panelvision, the Westinghouse successor company, which held the CdSe process license. Most other active-matrix development work at this time was shifting to amorphous silicon, however.
Litton designers did enjoy some success in developing displays in their research facility - enough so that they won several military display contracts. As a result, Canadian government officials agreed to invest in the company to establish a manufacturing line. Their investment of about $40 million, represents about a quarter of the total committed to the facility since 1994, Wright says.
One of the advantages of CdSe was supposed to be its superior producibility. By having a semiconductor material with better electrical characteristics than amorphous silicon, designers could relax some fabrication tolerances. That in turn, should have led to higher yields and lower costs.
The reason the manufacturing operation was closed was a combination of technical problems and a changing economic environment. While the process worked well in research and development where attention to detail was high, switching to full production was problematic.
"CdSe is quite susceptible to contamination even from normal process materials like photoresist", Wright explains. "Maintaining cleanliness in a production environment with less trained personnel and longer cycle times, proved difficult. In addition, our customers became willing to compromise their display specs, making the use of COTS [commercial off-the-shelf] displays more acceptable to them. The market for customized displays just wasn`t there anymore."
The shutdown is affecting programs such as the U.S. Army FMC Bradley Fighting Vehicle, the Air Force C-130J turboprop aircraft, and the RAH-66 Comanche and Merlin EH-101 combat helicopters.
Each Merlin uses two 10-inch VGA displays in the cockpit and four 14-inch VGA displays for tactical use. Comanche uses 6-by-8-inch displays for flight instrumentation, map and sensor data, as well as 6.7-by-3.5-inch monochrome displays for warning and weapon status. The Bradley also uses the 6-by-8-inch color displays. The C-130J aircraft can use from four to six 8-by-10-inch portrait-mode displays for navigation, engine status, flight information, maps and forward-looking infrared sensors.
To maintain Litton`s commitment to these programs, experts have developed alternative solutions that steal a page from the play book of COTS supporters. "Some programs, like Merlin deliveries, will continue to receive displays from our existing CdSe R&D fab. Other programs are looking to use COTS displays, primarily with off-shore glass, to supply customer needs. This will have to be the solution for any volume program," notes Litton spokesman Peter Broadhurst.
Litton scientists had intentionally designed their CdSe displays to be pin compatible with alternative amorphous silicon displays so customers could source either type and have them both work interchangeably. Visually, displays made from either material are indistinguishable. That makes switching from CdSe to amorphous silicon COTS displays that much easier. "All the back-end electronics remain the same," Broadhurst explains.
With yet another military display system provider embracing the COTS approach, the spotlight now moves to OIS and dpiX. Can they still beat the odds and remain viable suppliers of active-matrix LCDs?
