Semiconductor device and method for manufacturing the same
AssigneeHitachi, Ltd.
InventorsMayu Aoki, Kenichi Takeda, Kazuyuki Hozawa
Life of this patent
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Abstract
A semiconductor device including two silicon wafers stacked and bonded together with bumps of one wafer electrically coupled with those of the other wafer, in which generation of voids on the junction surface between the silicon wafers is suppressed. Due to a recess made in the surface of a buried conductive film, a cavity is formed in the junction surface between the silicon wafers. The ends of the cavity extend to the periphery of the junction surface between the silicon wafers. This allows the air trapped on the junction surface between the silicon wafers to get out through the cavity, thereby reducing the possibility of generation of voids on the junction surface.
Claims20
A semiconductor device having a first substrate with a first electrode formed on one surface and a second substrate with a second electrode formed on one surface, the first electrode and the second electrode being electrically coupled by bonding of the one surface of the first substrate and the one surface of the second substrate,
- wherein a first insulating film is formed on the one surface of the first substrate;
- wherein the first electrode is formed inside a first bump hole, made in a first region of the first insulating film;
- wherein a first conductive film of the same material as the first electrode is formed inside a first channel made in a second region of the first insulating film;
- wherein a surface level of the first electrode is the same as a surface level of the first insulating film;
- wherein a recess having a surface level lower than the surface level of the first insulating film is made in a surface of the first conductive film;
- and
- wherein ends of the first channel extend to a periphery of the first substrate.
A method for manufacturing a semiconductor device having a first substrate with a first electrode formed on one surface and a second substrate with a second electrode formed on one surface, the first electrode and the second electrode being electrically coupled by bonding of the one surface of the first substrate and the one surface of the second substrate,
- in forming the first electrode on the one surface of the first substrate, comprising the steps of:
- (a) forming a first insulating film on the one surface of the first substrate;
- (b) making a first bump hole in a first region of the first insulating film and making a first channel in a second region of the first insulating film with ends extending to a periphery of the first substrate;
- (c) forming, on an upper surface of the first insulating film and inside the first bump hole and the first channel, a first conductive film having such a thickness to fill an inside of the first bump hole and not completely fill an inside of the first channel;
- and
- (d) polishing the first conductive film using a chemical mechanical polishing technique until there is no level difference between an upper surface of the first conductive film buried in the first bump hole and an upper surface of the first insulating film, thereby forming, inside the first bump hole, the first electrode including the first conductive film,
- wherein at the step (d), a recess having a surface level lower than the surface level of the first insulating film is made in a surface of the first conductive film buried in the first channel.
A semiconductor device having a first substrate with a first electrode formed on one surface and a second substrate with a second electrode formed on one surface, the first electrode and the second electrode being electrically coupled by bonding of the one surface of the first substrate and the one surface of the second substrate,
- wherein a first insulating film is formed on the one surface of the first substrate;
- wherein the first electrode is formed inside a first bump hole made in a first region of the first insulating film;
- wherein a first channel having no electrode therein is disposed in a second region of the first insulating film, and a surface of a material disposed in said first channel is recessed with respect to a surface of the first insulating film.
Dependencies are inferred from the claim text.