Tantalum resistors with gold contacts

Claim 2

AN ELECTRICAL DEVICE COMPRISING A RESISTIVE ELEMENT FORMED BY A THIN METAL STRIP BORNE BY A RIGID, ELECTRICALLY INSULATING SUBSTRATE, AND A PLURALITY OF CONTACT MEANS FOR SAID RESISTIVE ELEMENT, SAID RESISTIVE ELEMENT FORMED OF A TANTALUM STRIP AND A SUPERPOSITION OF A LAYER OF MOLYBDENUM AND A LAYER OF GOLD, WITH A GOLD DOME DISPOSED ON EACH OF SAID CONTACT MEANS.

Claim 3

An electrical device according to claim 1, further comprising an exterior protective cover layer and a second layer of molybdenum interposed between said cover layer and said gold layer.

Claim 4

An electrical device according to claim 2, in which said cover layer consists of glass.

Claim 5

An electrical device according to claim 3, further comprising a second gold layer between said second molybdenum layer and said cover layer.

Claim 6

An electrical device according to claim 1 in which said substrat is made of silicon covered by a layer of silica.

Claim 7

An electrical device according to claim 1 in which the thickness of said tantalum strip is between 500 and 1,000 A.

Claim 8

An electrical device according to claim 1 in which the thickness of said molybdenum layer is approximately 1,500 A.

Claim 9

An electrical device according to claim 1 in which the thickness of said gold layer is approximately 10,000 A.

Claim 10

An electrical device according to claim 1 in which the height of said gold domes is approximately 10 microns.

Claim 11

An electrical device according to claim 1 further comprising a gold interconnection layer superposed upon the bottom face of said substrate.

Claim 12

An electrical device comprising: a resistive element formed by a tantalum strip of between 500 and 1,000 A in thickness, borne by a rigid substrate formed by silicon covered by a layer of silica and superposed with a gold interconnection layer upon the bottom face thereof, said resistive element superposed with a first molybdenum layer of approximately 1,500 A in thickness, a first gold layer of approximately 10,000 A in thickness, a second molybdenum layer, a second gold layer, and an exterior protective cover layer of glass enclosing said resistive element; and a plurality of contact means for said resistive element, each comprising a gold dome of approximately 10 microns in height.

Claim 13

An electrical device comprising: a resistive element formed by a tantalum strip of between 500 and 1,000 A in thickness, borne by a rigid substrate formed by silicon covered by a layer of silica and superposed with a gold interconnection layer upon the bottom face thereof, said resistive element superposed with a first molybdenum layer of approximately 1,500 A in thickness, a first gold layer of approximately 10,000 A in thickness, a second molybdenum layer, a second gold layer, and an exterior protective cover layer of glass enclosing said resistive element; and a plurality of contact means for said resistive element, each comprising a gold dome of approximately 10 microns in height.

Claim 14

An electrical system comprising a plurality of subsystems, each subsystem comprising two end-to-end electrical devices according to claim 1, and arranged so that one end of each subsystem is connected to a common central contact, the other end of each subsystem is connected to a common contact forming a peripheral line surrounding the totality of subsystems, and points common to two resistive elements of a subsystem each comprise a subsystem contact, with the central contact, peripheral contact, and each subsystem contact being provided with a gold dome.