Method for polymer-assisted chip transfer

• US 10,559,486 B1
• Filed: 01/10/2018
• Issued: 02/11/2020
• Est. Priority Date: 01/10/2018
• Status: Active Grant

• Current Assignee: META Platforms Technologies LLC (Meta Platforms, Inc. (f/k/a Facebook, Inc.))
• Original Assignee: Facebook Technologies, LLC (Meta Platforms, Inc. (f/k/a Facebook, Inc.))
• Inventors: Brodoceanu, Daniel, Saketi, Pooya, Torrents Abad, Oscar, Pourchet, Allan, Hughes, Patrick Joseph, Moh, Karsten
• Primary Examiner(s): Chan, Sing P
• Application Number:
  US15/867,400
• Time in Patent Office: 762 Days
• Field of Search: 156247, 156 29, 156289, 1563071, 1563073, 1563075, 1563082, 1563096, 1563099, 156310, 156314, 156315, 156320, 156323, 156714, 156715, 156719, 156249
• CPC Class Codes: B32B 2457/14 Semiconductor wafers
• CPC Class Codes: B32B 37/12 characterised by using adhesives
• CPC Class Codes: B32B 38/10 Removing layers, or parts of layers, mechanically or chemically
• CPC Class Codes: H01L 21/6835 using temporarily an auxiliary support
• CPC Class Codes: H01L 2221/68363 used in a transfer process involving transfer directly from an origin substrate to a target substrate without use of an intermediate handle substrate
• CPC Class Codes: H01L 2221/68368 used in a transfer process involving at least two transfer steps, i.e. including an intermediate handle substrate
• CPC Class Codes: H01L 2221/68381 Details of chemical or physical process used for separating the auxiliary support from a device or wafer
• CPC Class Codes: H01L 33/007 comprising nitride compounds
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/32 containing nitrogen

Abstract

One or more chips are transferred from one substrate to another by using one or more polymer layers to secure the one or more chips to an intermediate carrier substrate. While secured to the intermediate carrier substrate, the one or more chips may be transported or put through further processing or fabrication steps. To release the one or more chips, the adhesion strength of the one or more polymer layers is gradually reduced to minimize potential damage to the one or more chips.

Claims

1. A method comprising:

depositing a first adhesive layer on a first substrate, the first adhesive layer comprises a first material;

drying the first adhesive layer;

providing a second substrate with one or more chips attached;

placing the one or more chips on the first substrate through the first adhesive layer, the one or more chips attached to the second substrate;

depositing a second adhesive layer on the first substrate, the second adhesive layer covering edges of the second substrate and an edge portion of at least one of the one or more chips, the second adhesive layer not covering other portions of the one or more chips, the second adhesive layer made of a second material that is different from the first material, at least one of the first and second materials being a polymer material;

performing laser lift-off on an interface of the one or more chips and the second substrate;

removing at least the portions of the second adhesive layer covering the edges of the second substrate after performing the laser lift-off;

removing the second substrate from the one or more chips after performing the laser lift-off;

softening the first adhesive layer after removing the second substrate; and

removing the one or more chips from the first substrate.

2. The method of claim 1, wherein the one or more chips are weighted during the placement.

3. The method of claim 1, wherein the second adhesive layer is deposited via injection.

4. The method of claim 1, wherein softening the first adhesive layer comprises heating the first substrate to at least a first glass transition temperature of the first adhesive material.

5. The method of claim 1, wherein removing the second adhesive layer comprises dissolving the second adhesive layer in a solvent in which the second adhesive material is soluble, the first adhesive material not being soluble in the solvent.

6. The method of claim 5, wherein the solvent is water.

7. The method of claim 1, wherein the first adhesive material is polyvinyl acetate, and the second adhesive material is polyvinyl alcohol.

8. The method of claim 1, wherein the first adhesive material is polyvinyl pyrrolidone, and the second adhesive material is polyvinyl butyral.

9. The method of claim 1, wherein the first substrate is made of is a hard material.

10. The method of claim 9, wherein the first substrate is made of glass.

11. The method of claim 1, wherein the second substrate is made of sapphire.

12. The method of claim 1, wherein the first adhesive layer is approximately 1 micrometer thick.

13. A method comprising:

securing one or more chips to a first substrate by;

depositing a first adhesive layer on the first substrate, the first adhesive layer comprising a first material;

providing a second substrate with one or more chips attached;

placing one or more chips on the first substrate through the first adhesive layer, the one or more chips attached to the second substrate; and

depositing a second adhesive layer on the first substrate, the second adhesive layer covering edges of the second substrate and an edge portion of at least one of the one or more chips, the second adhesive layer not covering other portions of the one or more chips, the second adhesive layer made of a second material that is different from the first material, at least one of the first and second materials being a polymer material; and

detaching the one or more chips from the first substrate by;

removing the second adhesive layer from the first substrate;

softening the first adhesive layer after removing the second adhesive layer; and

removing the one or more chips from the first substrate after softening the first adhesive layer.

14. The method of claim 13, further comprising:

transporting the one or more chips while the one or more chips are secured to the first substrate.

15. The method of claim 13, further comprising:

performing one or more fabrication steps on the one or more chips while secured to the first substrate.

16. The method of claim 13, wherein the second adhesive layer is deposited via injection.

17. The method of claim 13, wherein removing the second adhesive layer comprises dissolving the second adhesive layer in a solvent in which the second adhesive material is soluble, the first adhesive material not being soluble in the solvent.

18. The method of claim 13, wherein the first material and the second material are different materials each selected from a group consisting of polyvinyl acetate, polyvinyl pyrrolidone, polyvinyl alcohol, and polyvinyl butyral.

19. The method of claim 13, wherein the first adhesive layer is approximately 1 micrometer thick.

20. The method of claim 13, wherein one of the first material and the second material is a wax.