STACK STRUCTURE AND METHOD OF MANUFACTURING THE SAME

• US 20080145970A1
• Filed: 02/14/2008
• Published: 06/19/2008
• Est. Priority Date: 03/23/2004
• Status: Active Grant

• Current Assignee: Casio Computer Company Limited
• Original Assignee: Casio Computer Company Limited
• Inventors: NOMURA, Masatoshi, TAKEYAMA, Keishi, TERAZAKI, Tsutomu, NAKAMURA, Osamu
• Granted Patent: US 8,133,338 B2
• Time in Patent Office: Days
• US Class Current: 438/109
• CPC Class Codes: B81B 2201/058 Microfluidics not provided for in B81B2201/051 - B81B2201/054
• CPC Class Codes: B81C 1/00119 Arrangement of basic structures like cavities or channels, e.g. suitable for microfluidic systems
• CPC Class Codes: B81C 2201/019 Bonding or gluing multiple substrate layers
• CPC Class Codes: B81C 2203/031 Anodic bondings
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

A stack structure is formed by stacking and bonding a plurality of substrates. The stack structure includes bonding films each of which is interposed in a bonding region between, adjacent glass substrates, and bonded to oxygen atoms in the glass of the substrate by anodic bonding.

Claims

1. A method of manufacturing a stack structure provided with a plurality of substrates including at least a first substrate, a second substrate including glass and a third substrate, comprising:

applying a first electric field acting in a direction between the first and second substrates to bond a first bonding film located between one of surfaces of the first substrate and one of surfaces of the second substrate to oxygen atoms in the glass in the second substrate, and also to effect anodic bonding of the first and second substrates to each other in such a manner as to incorporate alkali components in the glass in the second substrate into a buffer film provided on the other surface of the second substrate, and

applying a second electric field acting in the same direction as the first electric field, between the second substrate and the third substrate including glass to bond a second bonding film which is located between the other surface of the second substrate and one of the surfaces of the third substrate, to oxygen atoms in the glass of the second substrate, and also to effect anodic bonding of the second and third substrates in such a manner as to incorporate alkali components in the glass of the third substrate into a second buffer film provided on the other surface of the third substrate.

2. The method according to claim 1, wherein the anodic bonding between the first substrate and the second substrate and the anodic bonding between the second substrate and the third substrate are performed at different times.

3. The method according to claim 1, wherein the anodic bonding between the first substrate and the second substrate and the anodic bonding between the second substrate are performed at the same time.

4. The method according to claim 1, wherein at least one of the first and second bonding films comprises a material having at least one of a metal and an alloy each having a melting point of 2,000°

C. or higher, when said at least one of the first and second bonding films is not bonded to oxygen by anodic bonding.

5. The method according to claim 1, wherein at least one of the first and second bonding films has a material comprising at least one of Ta, W, Mo, TaSi2, WSi2 and MoSi2, when said at least one of the first and second bonding films is not bonded to oxygen by anodic bonding.

6. The method according to claim 1, wherein at least one of the first and second buffer films has a material having a resistivity lower than a resistivity of at least one of the first and second substrates.

7. The method according to claim 1, wherein at least one of the first and second buffer films comprises an amorphous oxide.

8. The method according to claim 1, wherein at least one of the first and second buffer films is formed of at least one of a compound comprising Ta, Si, and O, a compound comprising La, Sr, Mn, and O, and lead glass.

9. The method according to claim 1, wherein the alkali components in at least one of the glass in the second substrate and the glass in the third substrate comprises at least one of Na and Li.

10. A method of manufacturing a stack structure provided with a plurality of substrates, comprising:

manufacturing a plurality of stack structures according to the method recited in claim 1, and

applying an electric field acting in the same direction as the first and second electric fields between the stack structures, through a bonding film located therebetween to effect anodic bonding between the stack structures.

11. A method of manufacturing a stack structure provided with a plurality of structures, comprising:

bonding a first substrate, which is included in the plurality of substrates and which comprises one of silicon and glass, to oxygen atoms in glass in a second substrate included in the plurality of substrates, and also to effect anodic bonding between the first and second substrates in such a manner as to incorporate alkali components in the glass in the second substrate into a buffer film provided on a surface of the second substrate to which the first substrate is not bonded; and

bonding a bonding film provided between the second substrate and a third substrate, which is included in the plurality of substrates and which comprises glass, to oxygen atoms in the glass in the second substrate, by applying an electric field acting as in the anodic bonding between the first and second substrates, and effecting anodic bonding between the second and third substrates in such a manner as to incorporate alkali components in the glass in the third substrate into a buffer film provided on a surface of the third substrate to which the second substrate is bonded.