Zinc oxide thin film electroluminescent devices
AssigneeGroup IV Semiconductor Inc.
InventorJean-Paul Noel
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Abstract
A thin film electro-luminescent device (TFEL) includes an active layer made of a direct bandgap semiconductor material, e.g. zinc oxide, doped with exciton binding centers, such as aluminum, in small amounts, e.g. 0.001 at % to 30.0 at %. The exciton binding centers prevent free excitons, created by impact ionization, from diffusing toward and recombining at native defect centers. To provide a columnar structure, a polycrystalline seed layer is deposited first to provide a template, followed by the deposition of an overlying layer forming columns in accordance with the template.
Claims20
A method of fabricating a thin film electro-luminescent (TFEL) device comprising:
- a) providing a substrate;
- b) depositing an active layer of zinc oxide doped with exciton binding centers on the substrate;
- and
- c) mounting electrodes on either side of the active layer for applying an electric field thereto;
- wherein step b) comprises:
- depositing a seed layer comprised of zinc oxide doped with exciton binding centers forming hexagonal grains;
- and depositing an overlying layer comprised of zinc oxide doped with exciton binding centers that grows in a columnar structure using the underlying seed layer as a template.
Dependencies are inferred from the claim text.