Alumina insulation for coating implantable components and other microminiature devices
First Claim
1. A method of selectively applying a ceramic coating to an object, comprising:
- (a) forming a layer of metal over the object;
(b) forming a layer of photosensitive polyamide over the metal layer;
(c) applying a mask over the object for exposing areas of the polyamide layer that are formed over portions of the metal layer where the ceramic layer is not to be applied;
(d) exposing the object to radiation through the mask such that exposed areas of the polyamide layer are polymerized and unexposed areas of the polyamide layer remain unpolymerized;
(e) removing the unpolymerized areas of the polyamide layer;
(f) forming a layer of ceramic material over the object such that first portions of the ceramic layer are formed over the polymerized areas of the polyamide layer and second portions of the ceramic layer are formed over the metal layer;
(g) scribing the first portions of the ceramic layer;
(h) soaking the object in a solution for removing the first portions of the ceramic layer and the polymerized areas of the polyamide layer; and
(i) removing the first portions of the ceramic layer and the polymerized areas of the polyamide layer.
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Accused Products
Abstract
A protective, biocompatible coating or encapsulation material protects and insulates a component or device intended to be implanted in living tissue. The coating or encapsulation material comprises a thin layer or layers of alumina, zerconia, or other ceramic, less than 25 microns thick, e.g., 5–10 microns thick. The alumina layer(s) may be applied at relatively low temperature. Once applied, the layer provides excellent hermeticity, and prevents electrical leakage. Even though very thin, the alumina layer retains excellent insulating characteristics. In one embodiment, an alumina layer less than about 6 microns thick provides an insulative coating that exhibits less than 10 pA of leakage current over an area 75 mils by 25 mils area while soaking in a saline solution at temperatures up to 80° C. over a three month period.
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Citations
18 Claims
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1. A method of selectively applying a ceramic coating to an object, comprising:
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(a) forming a layer of metal over the object; (b) forming a layer of photosensitive polyamide over the metal layer; (c) applying a mask over the object for exposing areas of the polyamide layer that are formed over portions of the metal layer where the ceramic layer is not to be applied; (d) exposing the object to radiation through the mask such that exposed areas of the polyamide layer are polymerized and unexposed areas of the polyamide layer remain unpolymerized; (e) removing the unpolymerized areas of the polyamide layer; (f) forming a layer of ceramic material over the object such that first portions of the ceramic layer are formed over the polymerized areas of the polyamide layer and second portions of the ceramic layer are formed over the metal layer; (g) scribing the first portions of the ceramic layer; (h) soaking the object in a solution for removing the first portions of the ceramic layer and the polymerized areas of the polyamide layer; and (i) removing the first portions of the ceramic layer and the polymerized areas of the polyamide layer. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18)
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Specification