Process for lift off and handling of thin film materials

• US 6,214,733 B1
• Filed: 11/17/1999
• Issued: 04/10/2001
• Est. Priority Date: 11/17/1999
• Status: Expired due to Fees

• Current Assignee: Eloy Technology, LLC (Concert Technology Corporation)
• Original Assignee: Eloy Technology, LLC (Concert Technology Corporation)
• Inventors: Sickmiller, Mike E.
• Primary Examiner(s): Smith, Matthew
• Assistant Examiner(s): ROCCHEGIANI, RENZO
• Application Number:
  US09/442,030
• Time in Patent Office: 510 Days
• Field of Search: 438/458, 438/459, 438/479, 438/492, 438/977, 438/691, 117/915
• US Class Current: 438/691
• CPC Class Codes: H01L 21/6835 using temporarily an auxiliary support
• CPC Class Codes: H01L 2221/68309 Auxiliary support including alignment aids
• CPC Class Codes: H01L 2221/68359 used as a support during manufacture of interconnect decals or build up layers
• 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 2224/83192 wherein the layer connectors are disposed only on another item or body to be connected to the semiconductor or solid-state body
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/01322 Eutectic Alloys, i.e. obtained by a liquid transforming into two solid phases
• CPC Class Codes: H01L 2924/12041 LED
• CPC Class Codes: Y10S 438/915 Amphoteric doping
• CPC Class Codes: Y10S 438/977 Thinning or removal of substrate

Abstract

A process for lift-off of at least one thin film layer situated on a substrate is disclosed, including the steps of: depositing a support layer such as polymer on the thin film layer, wherein the support layer maintains the structural integrity of the thin film layer; attaching a rigid carrier superstrate to the support layer; and removing at least a portion of the substrate, wherein the thin film layer remains attached to the carrier superstrate via the support layer. After removing the substrate, the thin film layer is attached to a host substrate, and the carrier superstrate is removed from the thin film layer to leave the thin film layer attached to the host substrate. Removing the carrier superstrate from the thin film layer can include mechanically detaching the carrier superstrate from the thin film layer, such that only selected segments of the thin film layer remain attached to the host substrate. Attaching the thin film layer to the host substrate can include selectively attaching segments of the thin film layer to the host substrate, such that when the carrier superstrate is removed, the selected segments of the thin film layer remain attached to the host substrate. The selective attachment can be by selectively depositing bonding material on segments of the host substrate, and aligning the thin film layer with the host substrate such that the selected segments of the thin film material are aligned with said segments of the host substrate, respectively.

Claims

1. A method for lift-off of at least one thin film layer situated on a substrate, comprising the steps of:

(a) depositing a support layer on the thin film layer, wherein the support layer maintains the structural integrity of the thin film layer;

(b) attaching a carrier superstrate to the support layer; and

(c) removing at least a portion of the substrate, wherein the thin film layer remains attached to the carrier superstrate via the support layer.

2. The method of claim 1 wherein step (b) includes the steps of bonding the carrier superstrate to the support layer.

3. The method of claim 1, wherein step (b) includes the steps of using an adhesive layer between the carrier superstrate and the support layer to attach the carrier superstrate to the support layer.

4. The method of claim 1 further comprising the steps of processing the thin film layer after step (c).

5. The method of claim 4 further comprising the steps of processing the thin film layer after step (c) to form thin film devices.

6. The method of claim 1, wherein the carrier superstrate comprises a rigid superstrate.

7. The method of claim 1, wherein the support layer comprises a polymer layer.

8. The method of claim 1, wherein the thin film layer comprises thin film epitaxial materials.

9. The method of claim 1, wherein step (c) includes chemical processing of the substrate for removing said at least a portion of the substrate.

10. The method of claim 1 further comprising the steps of patterning the support layer to expose segments of the thin film layer before step (b), wherein after removing the substrate in step (c), unexposed segments of the thin film remain attached to the carrier superstrate via the support layer.

11. The method of claim 10 further comprising the steps of processing the exposed segments of the thin film layer to remove at least portions of said exposed segments of the thin film layer.

12. A method for lift-off of at least one thin film layer situated on a substrate, comprising the steps of:

(a) depositing a support layer on the thin film layer, wherein the support layer maintains the structural integrity of the thin film layer;

(b) attaching a carrier superstrate to the support layer;

(c) removing at least a portion of the substrate, wherein the thin film layer remains attached to the carrier superstrate via the support layer;

(d) attaching the thin film layer to a host substrate; and

(e) removing the carrier superstrate from the thin film layer to leave the thin film layer attached to the host substrate.

13. The method of claim 12, wherein the step of removing the carrier superstrate from the thin film layer further includes the steps of mechanically detaching the carrier superstrate from the thin film layer.

14. The method of claim 13, wherein the step of detaching the carrier superstrate from the thin film layer further includes the steps of pulling the carrier superstrate off the thin film layer by mechanical exertion.

15. The method of claim 12, wherein the step of attaching the thin film layer to the host substrate further includes the steps of bonding the thin film layer to the host substrate.

16. The method of claim 12 further comprising the steps of removing the support layer from the thin film layer after removing the carrier superstrate from the thin film layer.

17. The method of claim 12, wherein the steps of removing the carrier superstrate further includes the steps of removing the carrier superstrate from the thin film layer to leave only selected segments of the thin film layer attached to the host substrate.

18. The method of claim 12, wherein:

the steps of attaching the thin film layer to the host substrate further includes the steps of selectively attaching segments of the thin film layer to the host substrate; and

the steps of removing the carrier superstrate further includes the steps of removing the carrier superstrate from the thin film layer to leave said segments of the thin film layer attached to the host substrate.

19. The method of claim 18, wherein the steps of selectively attaching said segments of the thin film layer to the host substrate further includes the steps of:

selectively depositing bonding material on segments of the host substrate; and

aligning the thin film layer with the host substrate such that said segments of the thin film material are aligned with said segments of the host substrate, respectively.

20. A method for lift-off of thin film layers, comprising the steps of:

(a) depositing an epitaxial thin film layers over a sacrificial layer on a substrate;

(b) depositing a support layer on the thin film layers, wherein the support layer maintains the structural integrity of the thin film layers;

(c) attaching a carrier superstrate to the support layer; and

(d) removing at least a portion of the sacrificial layer to separate the thin film layers from the substrate, such that the thin film layers remains attached to the carrier superstrate via the support layer.

21. The method of claim 20 wherein step (c) includes the steps of bonding the carrier superstrate to the support layer.

22. The method of claim 20, wherein step (c) includes the steps of using an adhesive layer between the carrier superstrate and the support layer to attach the carrier superstrate to the support layer.

23. The method of claim 20 further comprising the steps of processing the thin film layers after step (d).

24. The method of claim 23 further comprising the steps of processing the thin film layers after step (d) to form thin film devices.

25. The method of claim 20 wherein the carrier superstrate comprises a rigid superstrate.

26. The method of claim 20 further comprising the steps of patterning the support layer to expose segments of one or more thin film layer before step (c), wherein after separating the substrate in step (d), unexposed segments of the thin film remain attached to the carrier superstrate via the support layer.

27. The method of claim 26 further comprising the steps of processing the exposed segments of the thin film layer to remove at least portions of said exposed segments of the thin film layer.