Tuneable dielectric films having low electrical losses

Details Tuneable dielectric films having low electrical losses Tuneable dielectric films having low electrical losses

1997-02-28

2000-08-01

Utech, Benjamin

Single-crystal, oriented-crystal, and epitaxy growth processes;

Processes of growth from solid or gel state

Using heat

427554, 427566, 4271263, 4272553, 4273762, 4273764, 20419222, C30B 100

Patent

active

060961279

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.

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