Lipseals and contact elements for semiconductor electroplating apparatuses
Disclosed herein are lipseal assemblies for use in electroplating clamshells which may include an elastomeric lipseal for excluding plating solution from a peripheral region of a semiconductor substrate and one or more electrical contact elements. The contact elements may be structurally integrated with the elastomeric lipseal. The lipseal assemblies may include one or more flexible contact elements at least a portion of which may be conformally positioned on an upper surface of the elastomeric lipseal, and may be configured to flex and form a conformal contact surface that interfaces with the substrate. Some elastomeric lipseals disclosed herein may support, align, and seal a substrate in a clamshell, and may include a flexible elastomeric upper portion located above a flexible elastomeric support edge, the upper portion having a top surface and an inner side surface, the later configured to move inward and align the substrate upon compression of the top surface.
1. A lipseal assembly for use in an electroplating clamshell for engaging and supplying electrical current to a semiconductor substrate during electroplating, the lipseal assembly comprising:
an elastomeric lipseal for engaging the semiconductor substrate during electroplating, wherein upon engagement the elastomeric lipseal substantially excludes plating solution from a peripheral region of the semiconductor substrate; and
one or more contact elements for supplying electrical current to the semiconductor substrate during electroplating, the one or more contact elements conformally positioned on an upper surface of the elastomeric lipseal and comprising a first exposed portion which contacts the peripheral region of the substrate upon engagement of the lipseal with the substrate;
wherein an engaging portion of the elastomeric lipseal which engages the substrate during electroplating is positioned relative to the first exposed portion of the electrical contact element such that during engagement said engaging portion of the lipseal compresses against the substrate prior to the first exposed portion of the electrical contact element making electrical contact with the substrate, wherein the one or more contact elements further comprise a second exposed portion for making an electrical connection with an electrical current source and a third exposed portion connecting the first and second exposed portions, the third exposed portion conformally positioned on the upper surface of the elastomeric lipseal; and
wherein the third exposed portion is pressed, glued, molded, or otherwise attached directly to a surface of the elastomeric lipseal.
2. The lipseal assembly of claim 1 , wherein the current source is a bus bar of the electroplating clamshell.
3. The lipseal assembly of claim 1 , wherein the engaging portion of the elastomeric lipseal includes a protrusion extending upwards and configured to be compressed by the semiconductor substrate and form a seal to substantially exclude the plating solution.
4. The lipseal assembly of claim 3 , wherein the first exposed portion of the electrical contact element is aligned with the protrusion of the elastomeric lipseal.
5. The lipseal assembly of claim 1 , wherein the elastomeric lipseal comprises a first inner diameter defining a substantially circular perimeter for excluding the plating solution from the peripheral region, and wherein the first exposed portion of the one or more contact elements defines a second inner diameter that is larger than the first inner diameter.
6. The lipseal assembly of claim 5 , wherein the magnitude of the difference between the first inner diameter and the second inner diameter is about or less than 0.5 mm.
7. The lipseal assembly of claim 6 , wherein the magnitude of the difference between the first inner diameter and the second inner diameter is about or less than 0.3 mm.