HERMETIC WAFER-TO-WAFER BONDING WITH ELECTRICAL INTERCONNECTION
First Claim
1. A method for forming an integrated circuit for an implantable medical device comprising:
- forming a first via in a first side of a first substrate;
forming a first conductive pad in the first via, wherein an exposed top surface of the first conductive pad is lower than a top surface of the first via;
forming a second via in a first side of a second substrate;
forming a second conductive pad in the second via, wherein an exposed top surface of the second conductive pad is lower than a top surface of the second via; and
reflowing the first and second conductive pads to form a single reflowed interconnect that completely fills a gap between the first and second vias.
1 Assignment
0 Petitions
Accused Products
Abstract
An implantable medical device (IMD) is disclosed. The IMD includes a first substrate having a front side and a backside. A first via is formed in the front side, the via extending from a bottom point in the front side to a first height located at a surface of the front side. A first conductive pad is formed in the first via, the first conductive pad having an exposed top surface lower than first height. A second substrate is coupled to the first substrate, the second substrate having a second via formed in the front side, the via extending from a bottom point in the front side to a second height located at a surface of the front side. A second conductive pad is formed in the second via, the second conductive pad having an exposed top surface lower than second height. The coupled substrates are heated until a portion of one or both conductive pads reflow, dewet, agglomerate, and merge to form an interconnect, hermetic seal, or both depending on the requirements of the device.
48 Citations
41 Claims
-
1. A method for forming an integrated circuit for an implantable medical device comprising:
-
forming a first via in a first side of a first substrate; forming a first conductive pad in the first via, wherein an exposed top surface of the first conductive pad is lower than a top surface of the first via; forming a second via in a first side of a second substrate; forming a second conductive pad in the second via, wherein an exposed top surface of the second conductive pad is lower than a top surface of the second via; and reflowing the first and second conductive pads to form a single reflowed interconnect that completely fills a gap between the first and second vias. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18)
-
-
19. An integrated circuit for an implantable medical device comprising:
-
means for forming a first via in a first side of a first substrate; means for forming a first conductive pad in the first via, wherein an exposed top surface of the first conductive pad is lower than a top surface of the first via; means for forming a second via in a first side of a second substrate; means for forming a second conductive pad in the second via, wherein an exposed top surface of the second conductive pad is lower than a top surface of the second via; and means for heating until at least a portion of first and second conductive pads reflow and form an interconnect that completely fills a gap between the first and second vias.
-
-
20. A method comprising:
-
forming a first wafer with a frontside and a backside; forming a second wafer with a frontside and a backside; coupling the frontside of the first wafer to the frontside of the second wafer; and polishing the frontside of either the first wafer or the second wafer such that only nonconductive material is contacted by a polishing device. - View Dependent Claims (21, 22, 24)
-
-
23. An integrated circuit for an implantable medical component comprising:
-
means for forming a first via in a first side of a first substrate; means for forming a first conductive pad in the first via, wherein an exposed top surface of the first conductive pad is lower than a top surface of the first via; means for forming a second via in a first side of a second substrate; means for forming a second conductive pad in the second via, wherein an exposed top surface of the second conductive pad is lower than a top surface of the second via; and means for heating until at least a portion of first and second conductive pads reflow and form an interconnect that completely fills a gap between the first and second vias. - View Dependent Claims (35, 36)
-
-
25. An implantable medical device comprising:
-
a first substrate having a front side and a backside; a first via formed in the front side, the via extending from a bottom point in the front side to a first height located at a surface of the front side; a first conductive pad formed in the first via, the first conductive pad having an exposed top surface lower than first height; a second substrate coupled to the first substrate, the second substrate having a second via formed in the front side, the via extending from a bottom point in the front side to a second height located at a surface of the front side; a second conductive pad formed in the second via, the second conductive pad having an exposed top surface lower than second height; and means for reflowing one of the first and second conductive pads to form a single reflowed interconnect. - View Dependent Claims (26, 27, 28, 29, 30, 31, 32, 33, 34, 37, 38, 39, 40, 41)
-
Specification