Sarnoff Corporation

Les Hozer

Ashok Narayan Prabhu

Attiganal Narayanaswamy Sreeram

Kalipada Palit

A plasma display device of the type having a composite back plate including a metal substrate and a ceramic barrier rib structure, is formed using a green ceramic tape which is a combination of two glasses, a primary glass which flows back during firing and a secondary glass that has a relatively high thermal coefficient of expansion. These glasses are combined in proportion to match the thermal coefficient of expansion of the metal substrate. Channels are formed on the inner surface of the back panel by laminating a green ceramic tape to the metal substrate and then soaking the laminated tape in a solvent before embossing the green tape to form the ribs. This soaking step enhances the flow of the green ceramic tape during the embossing process. The ceramic components of the green tape are formulated with a particle size 15 &mgr;m or more to enhance particle flow when the green tape is embossed. Electrodes are printed onto one or more of the green ceramic tape layers, by screen printing using a metal emulsion screen, prior to embossing such that the electrode layer covers all or substantially all of the green tape layer and the electrodes are separated by the embossing process. Alternatively, the electrodes are printed onto one or more of the green ceramic tape layers using a conductive ink which may be applied using an ink-jet printing technique. In another alternative, the electrodes are formed from sheets of conductive material and applied to the back panel either before or after the panel is embossed.

Method for making an embossed plasma display back panel

A plasma display device having a composite back panel including a metal substrate having a predetermined thermal coefficient of expansion (TCE) and a ceramic barrier rib structure which are co-fired at a pre-determined temperature, the ceramic barrier rib structure is composed from a first glass material having a TCE which is less than the TCE of the metal substrate, the first glass formulated to flow-back at the co-firing temperature; and a second glass material having a TCE which is greater than the TCE of the metal substrate, wherein the first and the second glass materials are mixed in a proportion to produce a composite ceramic material having a TCE which is substantially equal to the TCE of the metal substrate. The plasma display device having the ceramic barrier rib structure composed of the first and second glasses provides control of the TCE to minimize stresses in the final produce and assure panel flatness. A green ceramic tape defined by percentage weight formulation as: 40-70% glass 1, 1-15% glass 2, 10-30% solvent, 10-40% resin, wherein glass 1 is defined by percentage weight formulation as: 15-50% ZnO, 10-45% MgO, 5-30%, BaO, 10-45% SiO.sub.2, and glass 2 is defined by percentage weight formulation as: 10-80% SiO.sub.2, 5-60% B.sub.2 O.sub.3, 5-30% BaO, 0-60% Al.sub.2 O.sub.3. The green tape ceramic including the aforementioned glass 1 and glass 2 promotes solidification and densification.

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Lawrenceville, NJ, United States of America

Les Hozer