Heterogeneous annealing method and device

• US 8,735,219 B2
• Filed: 08/30/2012
• Issued: 05/27/2014
• Est. Priority Date: 08/30/2012
• Status: Active Grant

• Current Assignee: Invensas Bonding Technologies, Inc. (Adeia Inc.)
• Original Assignee: Ziptronix Incorporated (Adeia Inc.)
• Inventors: Enquist, Paul M., Fountain, Gaius Gillman
• Primary Examiner(s): Maldonado, Julio J
• Assistant Examiner(s): FORTICH, RODOLFO D
• Application Number:
  US13/599,023
• Publication Number:
  US 20140061949A1
• Time in Patent Office: 635 Days
• Field of Search: 438/107, 438/109, 438/406, 438/455, 438/459, 438/618, 438/974
• US Class Current: 438/107
• CPC Class Codes: H01L 21/2007 Bonding of semiconductor wafers to insulating substrates or to semiconducting substrates using an intermediate insulating layer H01L21/2011 takes precedence; bonding of semiconductor wafers to semiconductor wafers for junction formation H01L21/187
• CPC Class Codes: H01L 21/6835 using temporarily an auxiliary support
• CPC Class Codes: H01L 21/76898 formed through a semiconductor substrate
• CPC Class Codes: H01L 2221/68359 used as a support during manufacture of interconnect decals or build up layers
• CPC Class Codes: H01L 2224/29147 Copper [Cu] as principal constituent
• CPC Class Codes: H01L 2224/29155 Nickel [Ni] as principal constituent
• CPC Class Codes: H01L 2224/83053 Bonding environment
• CPC Class Codes: H01L 2224/83201 Compression bonding
• CPC Class Codes: H01L 2225/06541 Conductive via connections through the device, e.g. vertical interconnects, through silicon via [TSV] manufacturing via connections per se H01L21/76898
• CPC Class Codes: H01L 23/49866 characterised by the materials materials of the substrates H01L23/14, of the lead-frames H01L23/49579
• CPC Class Codes: H01L 24/32 of an individual layer connector
• CPC Class Codes: H01L 24/83 using a layer connector
• CPC Class Codes: H01L 25/0657 Stacked arrangements of devices
• CPC Class Codes: H01L 25/50 Multistep manufacturing processes of assemblies consisting of devices, each device being of a type provided for in group H01L27/00 or H01L29/00 H01L21/50 takes precedence
• CPC Class Codes: H01L 27/0688 Integrated circuits having a three-dimensional layout
• CPC Class Codes: H01L 28/26 with an active material comprising an organic conducting material, e.g. conducting polymers
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

A method of integrating a first substrate having a first surface with a first insulating material and a first contact structure with a second substrate having a second surface with a second insulating material and a second contact structure. The first insulating material is directly bonded to the second insulating material. A portion of the first substrate is removed to leave a remaining portion. A third substrate having a coefficient of thermal expansion (CTE) substantially the same as a CTE of the first substrate is bonded to the remaining portion. The bonded substrates are heated to facilitate electrical contact between the first and second contact structures. The third substrate is removed after heating to provided a bonded structure with reliable electrical contacts.

Claims

1. A method of integrating a first element having a first contact structure with a second element having a second contact structure, comprising:

bonding a first element with a first metal bonding structure directly to a second element with a second metal bonding structure;

thinning said first element to a thickness that would result in distortion of said first element if heated to a temperature to facilitate direct connections between the first and second direct metal bonding structure; and

attaching a third element having a thickness to reduce said distortion to the thinned first element;

heating bonded first, second, and third elements; and

forming electrical connections between said first and second metal bonding structures.

2. The method recited in claim 1, further comprising removing the third element.

3. The method recited in claim 1, wherein the bonding comprises applying pressure using a clamp.

4. The method recited in claim 3, comprising placing the first and second elements in a flexible container.

5. The method recited in claim 4, comprising evacuating the flexible container.

6. The method recited in claim 4, comprising applying pressure to the container.

7. A method of integrating a first element having a first surface with a first insulating material and a first contact structure with a second element having a second surface with a second insulating material and a second contact structure, comprising:

directly bonding the first insulating material to the second insulating material;

removing a portion of the second element to leave a remaining portion having a first thickness;

directly bonding a third element having a coefficient of thermal expansion (CTE) substantially the same as a CTE of the first element to the said remaining portion; and

heating the first and third elements and remaining portion to directly contact the first and second contact structures.

8. The method recited in claim 7, further comprising removing the third element.

9. The method recited in claim 7, wherein the first and second contact structures comprise nickel, the first element comprises a GaN/sapphire substrate, the second element comprises a silicon CMOS substrate, and the third element comprises a silicon substrate, the method comprising:

heating to a temperature in a range of 300-350°

C.

10. The method recited in claim 7, wherein the first element comprises a GaN/sapphire structure with sapphire substrate in the range of approximately 500-1000 micron thickness, the second element comprises a silicon CMOS substrate of 500-750 micron thickness, the method comprising:

heating to a temperature in a range of 75-150°

C.

11. The method recited in claim 7, wherein the first and second contact structures comprise copper, the first element comprises silicon oxide, the second element comprises silicon oxide, the method comprising:

heating to a temperature about 100°

C.

12. The method recited in claim 7, wherein the first element and the second element have a difference in coefficient of thermal expansion of less than 0.5 ppm/°

C.

13. The method recited in claim 7, wherein the first and third elements have substantially the same coefficient of thermal expansion.

14. The method recited in claim 13, wherein the second element has a coefficient of thermal expansion different from the first and third elements.

15. The method recited in claim 7, wherein the first thickness is in a range of 1-10 microns.

16. The method recited in claim 7, comprising:

directly bonding the third element having a coefficient of thermal expansion different from the CTE of the first element in a range of 0.3 to 1.0 ppm/°

C.

17. The method recited in claim 7, comprising:

directly bonding the third element having a coefficient of thermal expansion different from the CTE of the first element by less than about 0.3 ppm/°

C.

18. The method recited in claim 7, comprising:

directly bonding the third element having a coefficient of thermal expansion different from the CTE of the first element by less than about 0.5 ppm/°

C.

19. The method recited in claim 7, comprising:

directly bonding the third element having a coefficient of thermal expansion different from the CTE of the first element by less than about 1.0 ppm/°

C.

20. The method recited in claim 7, wherein at least one of the first and second contact structures is copper, comprising:

heating to a temperature in a range of 150-250°

C.

21. The method recited in claim 20, comprising:

forming at least one of the first and second contact structures to have a surface 0-10 nm below a surface of the respective first and second insulating material.

22. The method recited in claim 7, wherein at least one of the first and second contact structures is nickel, comprising:

heating to a temperature in a range of 250-350°

C.

23. The method recited in claim 22, comprising:

forming at least one of the first and second contact structures from to have a surface 0-10 nm below a surface of the respective first and second insulating material.

24. The method recited in claim 7, comprising:

thinning the third material to a thickness in a range of about 0.1-1 nm.

25. The method recited in claim 7, comprising:

thinning the third material to a thickness in a range of about 1-10 nm.

26. The method recited in claim 7, comprising:

thinning the third material to a thickness in a range of about 10-100 nm.

27. The method recited in claim 7, comprising:

thinning the third material to a thickness in a range of about 2-20 nm; and

heating to a temperature of at least 350°

C.

28. The method recited in claim 7, comprising:

forming a via filled with conductive material connected to at least one of the first and second contact structures.

29. The method recited in claim 7, wherein at least one of said first and second contact structures comprises a direct metal bonding structure.

30. The method recited in claim 7, wherein the bonding comprises applying pressure using a clamp.

31. The method recited in claim 30, comprising placing the first and second elements in a flexible container.

32. The method recited in claim 31, comprising evacuating the flexible container.

33. The method recited in claim 31, comprising applying pressure to the container.