Sputter deposition process for electroluminescent phosphors
AssigneeiFire Technology Inc.
InventorAlexander Kosyachkov
Life of this patent
Estimating the term…
Abstract
The invention is a novel sputter deposition process for thin film phosphors that provide high luminance and colors required for TV applications.
Claims50
A dual source sputtering method for the deposition of a thin film phosphor composition onto a substrate, said method comprising the steps of:
- providing a metal as a first source;
- providing a sulfur bearing compound as a second source;
- doping said first or second source with a rare earth activator;
- and
- applying sufficient current to the first and second sources in a sulfur containing atmosphere to effect sputtering of said first and second targets and deposition of said phosphor composition on said substrate.
A method for depositing a film onto a substrate, said method comprising the steps of:
- a) providing a substrate having a substrate surface,
- b) depositing a rare earth activated alkaline earth thioaluminate phosphor composition over the substrate surface, the composition being a laminated film with a periodic composition alternatively rich and poor in aluminum.
A dual source sputtering method for the deposition of a thin film phosphor composition onto a substrate, said method comprising the steps of:
- placing a metal as a first source and a sulfur bearing compound as a second source within a chamber having an atmosphere of hydrogen sulfide or sulfur vapours;
- doping said first or second source with a rare earth activator;
- and
- applying sufficient energy to said first and second target to cause sputtering thereof and a flux of atomic species of said first and second targets onto said substrate.
A thin film laminated phosphor comprising;
- alternate layers of metal sulfide and rate earth doped alkaline earth sulfide.
A thick dielectric electroluminescent display comprising;
- a rigid substrate;
- a lower electrode layer directly adjacent said substrate, said lower electrode layer comprising an electrically conductive metallic film;
- a thick film dielectric layer provided on an upper surface of said electrode layer;
- a phosphor film deposited on said thick film dielectric layer, said phosphor film comprising an alkaline earth thioaluminate phosphor film:
- and
- an upper electrode layer comprising an optically transparent electrically conductive film.
A method for preparing a thin film phosphor composition, said method comprising the steps of;
- placing a substrate with a reactive chamber;
- supplying a sputtering gas mixture of hydrogen sulfide at a pressure of about 5×10−3 torr to the reactive chamber;
- applying power in a ratio of about 1:1 to 5:1 to a first source of elemental aluminum and
- a second source of alkaline earth sulfide;
- aid first or second source additionally comprising an activator species of selected from the group consisting of cerium and europium;
- wherein applying said power to said first and second sources causes sputtering thereof and a flux of atomic species of said first and second targets onto said substrate to form a thin film alkaline earth thioaluminate phosphor composition.
Dependencies are inferred from the claim text.