Bonding apparatus and bonding method

1. A bonding apparatus comprising:

a first holder configured to hold a first substrate;

a second holder configured to suck a second substrate, oppose the second substrate to the first substrate, and bond the second substrate to the first substrate;

a first ring stage provided on an outer circumference of the first holder and configured to allow a first ring member provided on an outer edge of the first substrate to be mounted thereon;

a second ring stage provided on an outer circumference of the second holder and configured to allow a second ring member provided on an outer edge of the second substrate to be mounted thereon;

a first heater provided in the first ring stage; and

a second heater provided in the second ring stage.

2. The apparatus of claim 1 , wherein

the first heater heats the first ring member when the first ring member is attached to and detached from the first substrate mounted on the first holder, and

the second heater heats the second ring member when the second ring member is attached to and detached from the second substrate mounted on the second holder.

3. The apparatus of claim 1 , further comprising a ring suction portion provided in the second ring stage and configured to suck the second ring member.

4. The apparatus of claim 3 , wherein

the second holder includes a plurality of suction portions configured to suck the second substrate, and

the ring suction portion stops suction of the second ring member after the suction portions stop suction of the second substrate, when the first and second substrates are bonded to each other.

5. The apparatus of claim 1 , wherein

a top surface of the first ring member, which is opposed to the second ring member, is substantially flush with a bonding surface of the first substrate, and

a top surface of the second ring member, which is opposed to the first ring member, is substantially flush with a bonding surface of the second substrate.

6. The apparatus of claim 1 , wherein the second ring stage is provided to be movable toward the first ring stage in such a manner that a mounting surface of the second ring stage for the second ring member comes close to the first ring stage with respect to a mounting surface of the second holder for the second substrate.

7. The apparatus of claim 1 , further comprising a pushing portion provided at a center of the second holder and configured to push out the second substrate from the second holder toward the first substrate.

8. A bonding apparatus comprising:

a first holder configured to hold a first substrate;

a second holder configured to suck a second substrate, oppose the second substrate to the first substrate, and bond the second substrate to the first substrate;

a first ring stage provided on an outer circumference of the first holder and configured to allow a first ring member provided on an outer edge of the first substrate to be mounted thereon;

a second ring stage provided on an outer circumference of the second holder and configured to allow a second ring member provided on an outer edge of the second substrate to be mounted thereon; and

a ring suction portion provided in the second ring stage and configured to suck the second ring member.

9. The apparatus of claim 8 , wherein

the second holder includes a plurality of suction portions configured to suck the second substrate, and

the ring suction portion stops suction of the second ring member after the suction portions stop suction of the second substrate, when the first and second substrates are bonded to each other.

10. The apparatus of claim 8 , wherein

the first holder has a first surface that allows the first substrate to be mounted thereon and a second surface that is depressed from the first surface and allows the first ring member to be mounted thereon, an inner-circumferential-side surface of the first ring member mounted on the second surface and the first ring stage and the first surface being substantially flush with each other as mounting surfaces that allow the first substrate to be mounted thereon, and

the second holder has a third surface that allows the second substrate to be mounted thereon and a fourth surface that is depressed from the third surface and allows the second ring member to be mounted thereon, an inner-circumferential-side surface of the second ring member mounted on the fourth surface and the second ring stage and the third surface being substantially flush with each other as mounting surfaces that allow the second substrate to be mounted thereon.

11. The apparatus of claim 10 , wherein

an outer-circumferential-side surface of the first ring member mounted on the second surface and the first ring stage is substantially flush with a bonding surface of the first substrate mounted on the first surface and the inner-circumferential-side surface of the first ring member, and

an outer-circumferential-side surface of the second ring member mounted on the fourth surface and the second ring stage is substantially flush with a bonding surface of the second substrate mounted on the third surface and the inner-circumferential-side surface of the second ring member.

12. The apparatus of claim 8 , wherein the second ring stage is provided to be movable toward the first ring stage in such a manner that a mounting surface of the second ring stage for the second ring member comes close to the first ring stage with respect to a mounting surface of the second holder for the second substrate.

13. The apparatus of claim 8 , further comprising a pushing portion provided at a center of the second holder and configured to push out the second substrate from the second holder toward the first substrate.

14. A bonding method using a bonding apparatus that includes a first holder configured to hold a first substrate, a second holder configured to suck a second substrate, oppose the second substrate to the first substrate, and bond the second substrate to the first substrate, a first ring stage configured to allow a first ring member provided on an outer edge of the first substrate to be mounted thereon, and a second ring stage configured to allow a second ring member provided on an outer edge of the second substrate to be mounted thereon, the method comprising:

placing the first ring member on the first ring stage, and mounting the first substrate on the first holder with the first ring member arranged on the outer edge of the first substrate;

placing the second ring member on the second ring stage, and mounting the second substrate on the second holder with the second ring member arranged on the outer edge of the second substrate;

opposing the second substrate mounted on the second holder to the first substrate mounted on the first holder, bonding the second substrate to the first substrate, and bringing the second ring member into contact with the first ring member; and

detaching the first and second ring members from the bonded first and second substrates.

15. The method of claim 14 , wherein bonding between the first and second substrates spreads from a center of the first and second substrates to the outer edges, followed by contact between the first and second ring members.

16. The method of claim 14 , wherein

when the first substrate is mounted on the first holder with the first ring member arranged on the outer edge of the first substrate,

the first ring member is caused to expand on the first ring stage,

the first substrate is placed inside the first ring member that has expanded on the first holder, and

the first ring member is caused to contract to be attached to the first substrate, and

when the second substrate is mounted on the second holder with the second ring member arranged on the outer edge of the second substrate,

the second ring member is caused to expand on the second ring stage,

the second substrate is placed inside the second ring member that has expanded on the second holder, and

the second ring member is caused to contract to be attached to the second substrate.

17. The method of claim 14 , wherein the first and second ring members are caused to expand on the first ring stage, when the first and second ring members are detached from the bonded first and second substrates.

18. The method of claim 16 , wherein the first and second ring members are caused to thermally expand or thermally contract.

19. The method of claim 14 , wherein

when the first substrate is mounted on the first holder with the first ring member arranged on the outer edge of the first substrate, the first ring member having a depression in its inner circumferential portion,

the first substrate is placed on the depression of the first ring member and the first holder, and

the first substrate and the first ring member are sucked onto the first holder and the first ring stage, and

when the second substrate is mounted on the second holder with the second ring member arranged on the outer edge of the second substrate, the second ring member having a depression in its inner circumferential portion,

the second substrate is placed on the depression of the second ring member and the second holder, and

the second substrate and the second ring member are sucked onto the second holder and the second ring stage.

20. The method of claim 14 , wherein

when the first and second ring members are detached from the bonded first and second substrates,

the second ring member is separated from the first ring member and the bonded first and second substrates by sucking the first ring member and the first substrate to which the second substrate is bonded onto the first holder side, and sucking the second ring member onto the second ring stage side.