Suppression of interconnect stress migration by refractory metal plug
AssigneeWinbond Electronics Corp.
InventorChi-Fa Lin
Life of this patent
Estimating the term…
Abstract
An interconnect structure for use in semiconductor devices, comprising: (a) a thin and elongated aluminum wire connected to a first metal structure; and (b) a plurality of regularly spaced dummy tungsten plugs which are connected to the aluminum wire at one end and are buried in an underlying dielectric layer so that it is insulated at the other end. The dummy tungsten plugs absorb the mobile aluminum atoms generated through stress-induced migration when the interconnect structure is subject to a rapid temperature change, thus preventing the via bulging problem which could seriously damage the second metal structure above the first metal structure.
Claims16
An interconnect structure for use in semiconductor devices, comprising:
- (a) a thin and elongated aluminum wire connected to a first metal structure, said aluminum wire being also connected to at least one via which is formed in an overlying dielectric layer and is made of a first refractory metal, wherein said aluminum wire and said metal structure are buried in said overlying dielectric layer;
- and
- (b) at least one refractory plug which is connected to said aluminum wire at one end and is buried in an underlying dielectric layer so that it is insulated at the other end, said underlying dielectric being disposed below said overlying dielectric layer, and said refractory plug being made of a second refractory metal to absorb mobile aluminum atoms generated through stress-induced migration when said interconnect structure is subject to a rapid temperature change;
- (c) wherein said aluminum wire has a width less than about 0.6 μm.
An interconnect structure for use in semiconductor devices, comprising:
- (a) a thin and elongated aluminum wire connected to a first metal structure, said aluminum wire being also connected to at least one via which is formed in an overlying dielectric layer and is made of a first refractory metal, wherein said aluminum wire and said metal structure are buried in said overlying dielectric layer;
- and
- (b) at least one refractory plug which is connected to said aluminum wire at one end and is buried in an underlying dielectric layer so that it is insulated at the other end, said underlying dielectric being disposed below said overlying dielectric layer, and said refractory plug being made of a second refractory metal to absorb mobile aluminum atoms generated through stress-induced migration when said interconnect structure is subject to a rapid temperature change;
- (c) wherein said interconnect structure contains a plurality of said refractory plugs arranged in a regular spacing of about 5 μm.
An interconnect structure for use in semiconductor devices, comprising:
- (a) a thin and elongated aluminum wire connected to a first metal structure, said aluminum wire being also connected to at least one via which is formed in an overlying dielectric layer and is made of a first refractory metal, wherein said aluminum wire and said metal structure are buried in said overlying dielectric layer;
- and
- (b) at least one refractory plug which is connected to said aluminum wire at one end and is buried in an underlying dielectric layer so that it is insulated at the other end, said underlying dielectric being disposed below said overlying dielectric layer, and said refractory plug being made of a second refractory metal to absorb mobile aluminum atoms generated through stress-induced migration when said interconnect structure is subject to a rapid temperature change;
- (c) wherein said via contains at least a via hole which is void space not filled by said first refractory metal.
A semiconductor device containing an interconnect structure which prevents vias from being bulged under a stress-induced migration, said interconnect structure comprising:
- (a) a thin and elongated aluminum wire connected to a first metal structure, said aluminum wire being also connected to at least one via which is formed in an overlying dielectric layer and is made of a first refractory metal, wherein said aluminum wire and said metal structure are buried in said overlying dielectric layer;
- and
- (b) at least one refractory plug which is connected to said aluminum wire at one end and is buried in an underlying dielectric layer so that it is insulated at the other end, said underlying dielectric being disposed below said overlying dielectric layer, and said refractory plug being made of a second refractory metal to absorb mobile aluminum atoms generated through stress-induced migration when said interconnect structure is subject to a rapid temperature change;
- (c) wherein said aluminum wire has a width less than about 0.6 μm.
A semiconductor device containing an interconnect structure which prevents vias from being bulged under a stress-induced migration, said interconnect structure comprising:
- (a) a thin and elongated aluminum wire connected to a first metal structure, said aluminum wire being also connected to at least one via which is formed in an overlying dielectric layer and is made of a first refractory metal, wherein said aluminum wire and said metal structure are buried in said overlying dielectric layer;
- and
- (b) at least one refractory plug which is connected to said aluminum wire at one end and is buried in an underlying dielectric layer so that it is insulated at the other end, said underlying dielectric being disposed below said overlying dielectric layer, and said refractory plug being made of a second refractory metal to absorb mobile aluminum atoms generated through stress-induced migration when said interconnect structure is subject to a rapid temperature change;
- (c) wherein said interconnect structure contains a plurality of said refractory plugs arranged in a regular spacing of about 5 μm.
A semiconductor device containing an interconnect structure which prevents vias from being bulged under a stress-induced migration, said interconnect structure comprising:
- (a) a thin and elongated aluminum wire connected to a first metal structure, said aluminum wire being also connected to at least one via which is formed in an overlying dielectric layer and is made of a first refractory metal, wherein said aluminum wire and said metal structure are buried in said overlying dielectric layer;
- and
- (b) at least one refractory plug which is connected to said aluminum wire at one end and is buried in an underlying dielectric layer so that it is insulated at the other end, said underlying dielectric being disposed below said overlying dielectric layer, and said refractory plug being made of a second refractory metal to absorb mobile aluminum atoms generated through stress-induced migration when said interconnect structure is subject to a rapid temperature change;
- (c) wherein said via contains at least a via hole which is void space not filled by said first refractory metal.
Dependencies are inferred from the claim text.