Method of separating two layers of material from one another

• US 20030104678A1
• Filed: 12/20/2002
• Published: 06/05/2003
• Est. Priority Date: 10/01/1996
• Status: Active Grant

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Kelly, Michael, Stutzmann, Martin, Dimitrov, Roman, Handschuh, Robert, Ambacher, Oliver, Brandt, Martin
• Granted Patent: US 6,740,604 B2
• Time in Patent Office: Days
• US Class Current: 438/458
• CPC Class Codes: H01L 21/6835 using temporarily an auxiliary support
• CPC Class Codes: H01L 21/78 with subsequent division of the substrate into plural individual devices cutting to change the surface-physical characteristics or shape of semiconductor bodies H01L21/304
• CPC Class Codes: H01L 2221/68331 of passive members, e.g. die mounting substrate
• 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 2224/81801 Soldering or alloying
• CPC Class Codes: H01L 24/81 using a bump connector
• 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 2924/01004 Beryllium [Be]
• CPC Class Codes: H01L 2924/01005 Boron [B]
• CPC Class Codes: H01L 2924/01006 Carbon [C]
• CPC Class Codes: H01L 2924/01013 Aluminum [Al]
• CPC Class Codes: H01L 2924/01023 Vanadium [V]
• CPC Class Codes: H01L 2924/01033 Arsenic [As]
• CPC Class Codes: H01L 2924/01049 Indium [In]
• CPC Class Codes: H01L 2924/0106 Neodymium [Nd]
• CPC Class Codes: H01L 2924/01082 Lead [Pb]
• CPC Class Codes: H01L 2924/10329 Gallium arsenide [GaAs]
• CPC Class Codes: H01L 2924/12041 LED
• CPC Class Codes: H01L 2924/12042 LASER
• CPC Class Codes: H01L 2924/14 Integrated circuits
• CPC Class Codes: Y10S 438/977 : Thinning or removal of substrate

Abstract

A method of separating two layers of material from one another in such a way that the two separated layers of material are essentially fully preserved. An interface between the two layers of material at which the layers of material are to be separated, or a region in the vicinity of the interface, is exposed to electromagnetic radiation through one of the two layers of material. The electromagnetic radiation is absorbed at the interface or in the region in the vicinity of the interface and the absorbed radiation energy induces a decomposition of material at the interface.

Claims

1. A method of separating two layers of material from one another and substantially completely preserving each of the two layers of material, the method which comprises:

providing two layers of material having an interface boundary between the two layers, one of the two layers of material being a substrate and the other of the two layers of material being a semiconductor body having a layer of group III nitride material or a layer system of group III nitride materials;

irradiating the interface boundary between the two layers or a region in vicinity of the interface boundary with electromagnetic radiation through the substrate;

absorbing the electromagnetic radiation at the interface or in the region in the vicinity of the interface and initiating decomposition of group III nitride material of the layer or of the layer system and the formation of nitrogen gas.

2. The method according to claim 1, wherein the absorbing step comprises inducing the decomposition by converting an energy of the absorbed radiation into heat.

3. The method according to claim 1, wherein the absorbing step comprises inducing a decomposition of the interface boundary by generating nitrogen gas at the interface boundary with energy of the absorbed radiation.

4. The method according to claim 3, wherein the step of generating the nitrogen gas comprises inducing a method selected from the group consisting of chemical reactions and sublimation.

5. The method according to claim 1, wherein the irradiating step comprises radiating the electromagnetic radiation through the substrate.

6. The method according to claim 1, which comprises applying the semiconductor body for mechanical stabilization on a support material.

7. The method according to claim 1, wherein the irradiating step comprises exposing the material to one or more light pulses.

8. The method according to claim 1, wherein the irradiating step comprises irradiating with two or more coherent laser beams, producing an interference pattern in the exposure, and increasing a local light intensity.

9. The method according to claim 1, wherein the semiconductor body consists at least partially of a material selected from the group consisting of GaN, AlN, InN, mixed crystals thereof, layer sequences, layer structures, and component structures thereof.

10. The method according to claim 9, wherein the substrate consists essentially of a material selected from the group consisting of sapphire, LiAlO₂, LiGaO₂, MgAl₂O₄, ScAlMgO₄, and sic.

11. The method according to claim 9, wherein the substrate is a sapphire substrate and the semiconductor body includes a layer of a Ga compound selected from the group consisting of GaN and In_xGa_1-xN, and the irradiating step comprises separating the semiconductor from the sapphire substrate by exposing through the substrate with a third harmonic of a Nd:

YAG laser at a wavelength of 355 nm.

12. A method of producing a freestanding component structure, which comprises separating, in accordance with the method according to claim 5, a component structure from a substrate during or after a manufacture thereof.

13. The method according to claim 12, wherein the component structure is a component selected from the group consisting of diodes, light-emitting diodes, semiconductor lasers, transistors, and detectors.

14. The method according to claim 12, wherein the component is a semiconductor laser, and the method further comprises producing an optical resonator of the semiconductor laser by cleaving a freestanding component structure along crystallographic lattice planes of epitaxial layers.

15. A method of producing an optical component, which comprises, separating, in accordance with the method according to claim 1, an optical component from a substrate during or after a manufacture thereof.

16. The method according to claim 15, wherein the optical component is a component selected from the group consisting of diffraction gratings, thin film filters, optical couplers, and waveguides.

17. A method of separating two layers of material from one another and substantially completely preserving each of the two layers of material, the method which comprises:

providing two layers of material having an interface boundary between the two layers, one of the two layers of material being a substrate and the other of the two layers of material being a semiconductor body having a layer of group III nitride material or a layer system of group III nitride materials;

providing a sacrificial layer at the interface boundary, the sacrificial layer being formed of a group III nitride material or a layer system of group III nitride materials having an optical band gap smaller than a band gap of one of the two layers;

irradiating the interface boundary between the two layers or a region in vicinity of the interface boundary with electromagnetic radiation through one of the two layers;

absorbing the electromagnetic radiation at the interface or in the region in the vicinity of the interface with the sacrificial layer and initiating decomposition of group III nitride material of the layer or of the layer system and the formation of nitrogen gas.

18. The method according to claim 17, wherein the sacrificial layer consists at least partially of a nitride material selected from the group consisting of GaN, AlN, InN, and mixed crystals thereof.

19. The method according to claim 17, wherein the absorbing step comprises inducing the decomposition by converting an energy of the absorbed radiation into heat.

20. The method according to claim 17, wherein the irradiating step comprises radiating the electromagnetic radiation through the substrate.

21. The method according to claim 17, which comprises applying the semiconductor body for mechanical stabilization on a support material.

22. The method according to claim 17, wherein the irradiating step comprises exposing the material to one or more light pulses.

23. The method according to claim 17, wherein the irradiating step comprises irradiating with two or more coherent laser beams, producing an interference pattern in the exposure, and increasing a local light intensity.

24. The method according to claim 17, wherein the semiconductor body consists at least partially of a material selected from the group consisting of GaN, AlN, InN, mixed crystals thereof, layer sequences, layer structures, and component structures thereof.

25. The method according to claim 24, wherein the substrate consists essentially of a material selected from the group consisting of sapphire, LiAlO₂, LiGaO₂, MgAl₂O₄, ScAlMgO₄, and SiC.

26. The method according to claim 24, wherein the substrate is a sapphire substrate and the semiconductor body includes a layer of a Ga compound selected from the group consisting of GaN and In_xGa_1-xN, and the irradiating step comprises separating the semiconductor from the sapphire substrate by exposing through the substrate with a third harmonic of a Nd:

YAG laser at a wavelength of 355 nm.

27. A method of producing a freestanding component structure, which comprises separating, in accordance with the method according to claim 20, a component structure from a substrate during or after a manufacture thereof.

28. The method according to claim 27, wherein the component structure is a component selected from the group consisting of diodes, light-emitting diodes, semiconductor lasers, transistors, and detectors.

29. The method according to claim 27, wherein the component is a semiconductor laser, and the method further comprises producing an optical resonator of the semiconductor laser by cleaving a freestanding component structure along crystallographic lattice planes of epitaxial layers.

30. A method of producing an optical component, which comprises, separating, in accordance with the method according to claim 17, an optical component from a substrate during or after a manufacture thereof.

31. The method according to claim 30, wherein the optical component is a component selected from the group consisting of diffraction gratings, thin film filters, optical couplers, and waveguides.