Selective etching of thin films
AssigneeAgere Systems Guardian Corp.
InventorsLinus Albert Fetter, John Z. Pastalan
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Abstract
The invention removes a portion(s) of a material of interest, while leaving an adjacent or underlying electrode(s) intact. The material is exposed to a plasma containing at least two-halogen-containing gases. At least a portion of the material, for example a piezoelectric material, an oxygen-containing material, or a nitrogen-containing material, is etched by the plasma. By removing desired portions of this material, the device can have alternative or complex architecture. In addition, the propagation of shear waves is limited in the device.
Claims29
A method of removing a portion of a material layer comprising the steps of:
- a) providing a first electrode layer and a material layer adjacent to said first electrode layer;
- b) exposing a portion of said material layer to a plasma comprising at least two halogen-containing gases differing by at least their halogen content such that the combination of said halogen-containing gases effectively etches said portion of said material layer;
- and
- c) removing at least one of the halogen-containing gases from said plasma such that the resultant plasma has a substantially negligible etch rate on said first electrode layer.
Dependencies are inferred from the claim text.