Rapid thermal annealing of TFEL panels
AssigneePlanar Systems, Inc.
InventorsRichard T. Tuenge, Richard E. Coovert
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Abstract
A process for fabrication and annealing of TFEL panels includes the steps of depositing a laminar stack of thin films on a glass substrate containing a first set of electrodes, the laminar stack comprising at least one insulating layer and an EL phosphor layer and annealing the laminar stack under an array of high intensity flash lamps at a temperature exceeding 450.degree. C. for a period of between 15 and 240 seconds. The flash lamps bring the temperature of the laminar stack to the required high temperature very quickly and the stack is cooled very quickly at the end of the annealing period. This process conditions the EL phosphor layer but does not warp the glass substrate or damage the thin films.
Claims9
A rapid thermal annealing process for a thin-film electroluminescent panel, said panel having thin-film layers deposited on a glass substrate, said thin-film layers including a light emitting thin-film phosphor layer, comprising the steps of:
- (a) placing the thin-film electroluminescent panel on a support member, said support member having a high coefficient of energy absorption in the peak portion of the spectral energy range of a radiant heating element;
- (b) placing the panel on the support inside a radiant heating chamber utilizing said radiant heating element and uniformly radiantly heating the substrate and thin-film layers to a temperature which exceeds 500.degree. C. at a rate that exceeds 20.degree. per second;
- (c) maintaining the temperature achieved during step (b) for a time period of between 15 and 240 seconds;
- and
- (d) cooling the substrate and thin-film layers at a rate exceeding 10.degree. C. per second.
Dependencies are inferred from the claim text.