Electric lamp or space discharge component or device manufacturi – Process – With assembly or disassembly
Reexamination Certificate
2000-05-17
2004-04-06
Ramsey, Kenneth J. (Department: 2879)
Electric lamp or space discharge component or device manufacturi
Process
With assembly or disassembly
C445S025000, C430S312000, C430S313000, C430S320000, C430S325000
Reexamination Certificate
active
06716077
ABSTRACT:
BACKGROUND OF THE INVENTION
Flat panel displays, particularly those utilizing field emission display (FED) technology, employ a matrix-addressable array of cold, pointed field emission cathodes in combination with a luminescent phosphor screen. Individual field emission structures are sometimes referred to as vacuum microelectronic triodes. Each triode has the following elements: a cathode (emitter tip), a grid (also referred to as the “gate”), and an anode (typically, the phosphor-coated element to which emitted electrons are directed).
In order for proper display operation, which requires emission of electrons from the cathodes and acceleration of those electrons to a phosphor-coated screen, an operational voltage differential between the cathode array and the screen on the order of 1,000 volts is required. In order to prevent shorting between the cathode array and the screen, as well as to achieve distortion-free image resolution and uniform brightness over the entire expanse of the screen, highly uniform spacing between the cathode array and the screen is to be maintained.
As disclosed in U.S. Pat. No. 6,004,179, entitled, “Methods of Fabricating Flat Panel Evacuated Displays,” assigned to Micron Technology, Inc., which is incorporated herein by reference in its entirety, in a particular evacuated flat-panel field emission display utilizing glass spacer columns to maintain a separation of 250 microns (about 0.010 inches), electrical breakdown occurred within a range of 1,100 to 1,400 volts. All other parameters remaining constant, breakdown voltage will rise as the separation between screen and cathode array is increased. However, maintaining uniform separation between the screen and the cathode array is complicated by the need to evacuate the cavity between the screen and the cathode array to a pressure of less than 10
−6
Torr to enable field emission.
Small area displays (for example, those which have a diagonal measurement of less than 3 centimeters) can be cantilevered from edge to edge, relying on the strength of a glass screen having a thickness of about 1.25 millimeters to maintain separation between the screen and the cathode array. Since the displays are small, there is no significant screen deflection in spite of the atmospheric load. However, as display size is increased, the thickness of a cantilevered flat glass screen must be increased exponentially. For example, a large rectangular television screen measuring 45.72 centimeters (18 inches) by 60.96 centimeters (24 inches) and having a diagonal measurement of 76.2 centimeters (30 inches), must support an atmospheric load of at least 28,149 Newtons (6,350 pounds) without significant deflection. A glass screen (also known as a “faceplate”) having a thickness of at least 7.5 centimeters (about 3 inches) might well be required for such an application. Moreover, the cathode array structure must also withstand a like force without deflection.
A solution to cantilevered screens and cantilevered cathode array structures in the use of closely spaced, load-bearing, dielectric for very slightly conductive, e.g., resistance greater than 10 mega-ohm spacer structures. Each of the load-bearing structures bears against both the screen and the cathode array plate and thus maintains the two plates at a uniform distance between one another. By using load-bearing spacers, large area evacuated displays might be manufactured with little or no increase in the thickness of the cathode array plate and the screen plate.
SUMMARY OF THE INVENTION
A preferred embodiment of the invention is directed to support structures such as spacers or other layers of fixed geometry used to provide a uniform distance between two layers of a device. In accordance with a preferred embodiment, the spacers may be formed utilizing flow-fill deposition of a wet film in the form of a precursor such as silicon dioxide. Formation of spacers in this manner provides a homogeneous amorphous support structure that may be used to provide necessary spacing between layers of a device such as a flat panel display.
REFERENCES:
patent: 5314724 (1994-05-01), Tsukune et al.
patent: 5509840 (1996-04-01), Huang et al.
patent: 5587623 (1996-12-01), Jones
patent: 5614353 (1997-03-01), Kumar et al.
patent: 5619097 (1997-04-01), Jones
patent: 5658832 (1997-08-01), Bernhardt et al.
patent: 5808410 (1998-09-01), Pinker et al.
patent: 5840465 (1998-11-01), Kakinuma et al.
patent: 5851133 (1998-12-01), Hofmann
patent: 6004179 (1999-12-01), Alwan
patent: 6097097 (2000-08-01), Hirose
patent: 6159065 (2000-12-01), Jung et al.
Dobson et al., “Advanced SiO2Planarization Using Silane and H2O2”,Semiconductor International, Dec. 1994.
Gaillard et al., “Silicon dioxide chemical vapor deposition using silane and hydrogen peroxide”,J. Vac Sci. Technol., B 14(4), Jul./Aug. 1996.
Dickstein , Shapiro, Morin & Oshinsky, LLP
Micro)n Technology, Inc.
Ramsey Kenneth J.
Santiago Mariceli
LandOfFree
Method of forming flow-fill structures does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method of forming flow-fill structures, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of forming flow-fill structures will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3255274