US 6,096,127 AGranted

Tuneable dielectric films having low electrical losses

AssigneeSuperconducting Core Technologies, Inc.

InventorsDuane Brian Dimos, Robert William Schwartz, Mark Victor Raymond, Husam Niman Al-Shareef, Carl Mueller, David Galt

Life of this patent

Estimating the term…

patentgrep

Loading patent…

Abstract

The present invention is directed to a method for forming dielectric thin films having substantially reduced electrical losses at microwave and millimeter wave frequencies relative to conventional dielectric thin films. The reduction in losses is realized by dramatically increasing the grain sizes of the dielectric films, thereby minimizing intergranular scattering of the microwave signal due to grain boundaries and point defects. The increase in grain size is realized by heating the film to a temperature at which the grains experience regrowth. The grain size of the films can be further increased by first depositing the films with an excess of one of the compoents, such that a highly mobile grain boundary phase is formed.

Claims19

Dependent claims

A method for forming a thin film dielectric material, comprising:

selecting a superstoichiometric ratio between two or more components of a selected thin film dielectric material to provide a superstoichiometric composition;
forming the two or more components in the superstoichiometric ratio into the superstoichiometric composition;
applying the superstoichiometric composition to a crystalline substrate to form a layer of the superstoichiometric composition having an initial mean grain size, wherein a lattice mismatch between the crystalline substrate and the layer of the superstoichiometric composition is sufficient to cause epitaxial growth of the superstoichiometric composition on the crystalline substrate;
and
heating the layer to a temperature below the eutectic temperature to form an annealed layer of the thin film dielectric material having a final mean grain size, wherein the final mean grain size is more than the initial mean grain size and wherein the temperature is at least about 70% of the eutectic temperature.

2 more elements

Dependencies are inferred from the claim text.