US 6,551,916 B2Granted

Bond-pad with pad edge strengthening structure

AssigneeWinbond Electronics Corp.

InventorsShi-Tron Lin, Chin-Jong Chan

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Abstract

A bond pad structure for use in wire bonding application during the packaging operation of semiconductor devices which contains a bond frame structure for holding the bond pad in place to prevent bond pad peel-off problem. The bond pad structure is a laminated structure containing a metal bond pad layer, a middle dielectric layer, and an underlying layer formed above a wafer surface. A guard band structure is formed in a spaced apart relationship from the metal bond pad layer which is connected to the underlying layer by a hole-fill. The underlying layer can be a metal layer, a semiconductor layer such as a polysilicon layer, or any material layer which has good adhesion with the hole fill material. The guard band structure exerts a downward force against the middle dielectric layer to help keeping the middle dielectric layer in place. The guard band structure also creates a localized discontinuity in the middle dielectric layer to intercept cracks that may be formed in the middle layer around the edge of the metal bond pad which is believed a main cause of bond pad peel-off problem.

Claims9

Dependent claims

A method for fabricating a bond pad structure for use in an integrated circuit comprising the steps of:

(a) forming an underlying layer on a wafer surface;
(b) forming a middle dielectric layer on top of said underlying layer, said middle dielectric layer containing a first through-hole formed above said underlying layer;
(c) filling said first through-hole to form a hole fill;
(d) forming a top dielectric layer on top of said middle dielectric layer, said top dielectric layer containing a third through-hole immediately above said first through-hole, and a second through-hole which is spaced apart from said third through-hole, wherein said third through-hole is greater in cross-sectional area than said first through-hole and said second through-hole is substantially greater in cross-sectional area than said third through-hole;
(e) filling said second through-hole and said third through-hole to form a bond pad and a band element, respectively;
(f) where said band element is not connected to said bond pad, and said third through-hole is disposed in a close proximity to said second through-hole such that said band element is effective in intercepting crack that forms when said bond pad is under a stress.

3 more elements

Dependencies are inferred from the claim text.