Paid report on ctkt that was found by raging bull ctkt board.
By: wmo767 $$$$
Reply To: 13527 by wallstreeterww $$$$
Saturday, 27 Jan 2001 at 10:48 PM EST
Post #13537 of 13562
Wall,
Here's that whole article from Northern Light.
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Base Materials for Large Area Displays.
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Two new ceramic materials have proven to be effective substrate materials for large area flat
panel displays. Cetek Technologies, Inc., has developed perovskite and cordierite substrates
in large area formats that have the proper flatness and other properties for several of the
emerging flat panel display designs. The company's technical efforts have focussed on large
area substrates, beginning with alumina, and has developed a variety of special finishes for
them.
The company can now make substrates up to a square foot, and is extending the process to
larger areas. The process of making large area substrates is also being developed to include
other materials, and now includes substrates of ceramics such as cordierite, perovskite,
quartz, and silicon carbide. The company claims the process can be used on a wide range of
ceramics, which promises to provide substrates suitable for a larger number of electronic
applications.
The difficulty in creating large area substrates is in curling during heat treatment, resulting
from non-uniform heating. Extremely flat substrates promise to open up a range of new
applications for ceramic structures. Cetek's large area substrates show the same flatness as
commonly used four inch substrates: caster and camber are 1 2 mils per inch.
The substrates are fabricated in thin, large-area structures. At the panel printing and other
fabrication steps, a square foot substrate yields nine times the usable area as the more
standard four inch substrate. The result is considerable savings in direct labor and capital
equipment, in much the same way that larger semiconductor wafers are used in electronics.
In display technology in particular, the large area substrate is needed, rather than a substrate
cut up into small components as in semiconductors. Ultimately, flat panel developers need
substrates as large as the displays that are built, relieving them of the need to attach separate
substrates together to make a single display.
The function of the substrates in displays is largely structural, acting as the base upon which
all other layers are built. Ceramics are preferable because they are strong, corrosion proof
and resistant to high temperature processes. In multilayer applications, the substrates acts
more like a multilayer circuit board, in that the wiring is embedded in the backplane, and
acquires an electrical function, not just structural.
The rigidity of the substrates also helps to improve performance. For example, in field
emission displays, the dimensions between layers must be maintained within tight
tolerances, and so rigidity helps to ensure optimum performance. Electroluminescent and
plasma displays use large energy densities, and polymeric materials may distort or react to
the heat generated. Ceramics therefore provide more reliable performance.
The process of making large, thin substrates involves tailoring the thermal expansion
coefficient, so that the substrates can be perimeter bonded to other materials such as display
glass--in the case of some displays. The next required evolutionary step will be to bring in
multilayering to the large area substrates, which means that the substrate manufacturer can
supply the entire backplane of a display, complete with wiring.
In liquid crystal displays all the layers must be transparent so as to not block backlighting.
However, in virtually all other flat panel designs, such as field emission, glow discharge,
electroluminescent, etc., the light is generated internally. Therefore, an opaque backplane is
acceptable, and the material can be chosen on the basis of structural and electrical
properties, rather than simple transparency. Based on desirable properties, ceramics are
greatly preferable to the more commonly used polymeric materials.
As part of its strategy to develop multilayer substrates, Cetek has acquired MultiLythics, Inc.
(Greenville, SC). MultiLythics had already focused on perovskite materials in capacitor
manufacture, and already had a capability in high resolution printing and formation of a large
number of thin layers, all complementary to Cetek's efforts in multilayer substrates. The
company's cordierite and perovskite substrates are the only such substrates available in
areas a foot square. Cetek is planning 20 in. square substrate production for December of
this year. Multilayer substrates should be available within the year.
Contact: Fayiz Hilal, President, Cetek Technologies, Inc., 19 Commerce St., Poughkeepsie,
NY 12603; Tel: 914/452-3510, Email: fayiz@cetektechnologies.com.
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