US5141148A
Expired / Lapsed
US
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Method of anodic bonding a semiconductor wafer to an insulator
Assignee: Mitsubishi Electric Corp
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Filing: 1990-10-12
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Granted: 1992-08-25
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Expires: 2010-10-12
Abstract
Abstract An anodic bonding method in which a semiconductor wafer and an inorganic insulating material are bonded together includes the steps of forming a first metallic thin film having a strong contact with the inorganic insulating material on one surface of the inorganic insulating material. Then, a second metallic thin film which is stable in air is formed on the first metallic thin film. The inorganic insulating material is placed on the semiconductor wafer so that a surface of the inorganic insulating material opposite the first metallic film is brought into contact with the semiconductor wafer. Then, a DC voltage is applied across the first and second metallic thin films as a cathode and the semiconductor wafer as an anode while the inorganic insulating material and semiconductor wafer are heated. Since the first metallic thin film contacts with the inorganic insulating material strongly and fills all fine gaps, voids can be prevented from occurring in bonded layers. Further, since the second metallic thin film uniformly provides an electric field, uniform bonding can be obtained with high reproducibility.
Inventors
- 👤 Hideyuki Ichiyawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 05:52
CPC Classifications
H; H10; H10W; H10W72/00; H10W72/071; H10W72/073; H10W72/30; H10W72/07331; H10W72/07337; H10W72/351; H10W72/353; H10W72/354
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
110 words
An anodic bonding method in which a semiconductor wafer and an inorganic insulating material are bonded together consisting of: forming a film consisting of a single metal layer on the entire area of a surface of an inorganic insulating material; placing said inorganic insulating material on a semiconductor wafer so that a surface of the inorganic insulating material opposite the film is brought into contact with the semiconductor wafer; and apply a DC voltage across said film as a cathode and said semiconductor wafer as an anode while said semiconductor wafer and said inorganic insulating material are heated whereby the inorganic insulating material and the semiconductor wafer are bonded together.
Claim 2
Dependent Claim
110 words
An anodic bonding method in which a semiconductor wafer and an inorganic insulating material are bonded together consisting of: forming a film consisting of a single metal layer on the entire area of a surface of an inorganic insulating material; placing said inorganic insulating material on a semiconductor wafer so that a surface of the inorganic insulating material opposite the film is brought into contact with the semiconductor wafer; and apply a DC voltage across said film as a cathode and said semiconductor wafer as an anode while said semiconductor wafer and said inorganic insulating material are heated whereby the inorganic insulating material and the semiconductor wafer are bonded together.
Claim 3
Dependent Claim
22 words
The anodic bonding method as claimed in claim 1, wherein said film is selected from the group consisting of chromium and gold.
Claim 4
Dependent Claim
17 words
An anodic bonding method as claimed in claim 1, wherein said inorganic insulating material is Pyrex glass.
Claim 5
Dependent Claim
134 words
An anodic bonding method in which a semiconductor wafer and an inorganic insulating material are bonded together consisting of: forming a first film consisting of a first metal layer on the entire are of a surface of an inorganic insulating material; forming a second film consisting of a second metal layer which is stable in air on the first film; placing said inorganic insulating material on a semiconductor wafer so that a surface of the inorganic insulating material opposite the first film is brought into contact with the semiconductor wafer; and apply a DC voltage across said first and second films as a cathode and said semiconductor wafer as an anode while said semiconductor wafer and said inorganic insulating material are heated whereby the inorganic insulating material and the semiconductor wafer are bonded together.
Claim 6
Dependent Claim
134 words
An anodic bonding method in which a semiconductor wafer and an inorganic insulating material are bonded together consisting of: forming a first film consisting of a first metal layer on the entire are of a surface of an inorganic insulating material; forming a second film consisting of a second metal layer which is stable in air on the first film; placing said inorganic insulating material on a semiconductor wafer so that a surface of the inorganic insulating material opposite the first film is brought into contact with the semiconductor wafer; and apply a DC voltage across said first and second films as a cathode and said semiconductor wafer as an anode while said semiconductor wafer and said inorganic insulating material are heated whereby the inorganic insulating material and the semiconductor wafer are bonded together.
Claim 7
Dependent Claim
24 words
An anodic bonding method as claimed in claim 4, wherein said first film is selected from the group consisting of titanium, chromium, and zirconium.
Claim 8
Dependent Claim
27 words
An anodic bonding method as claimed in claim 4, wherein said second film is selected from the group consisting of nickel, cobalt, molybdenum, gold, silver, and platinum.
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