Generic layer transfer methodology by controlled cleavage process

• US 6,391,740 B1
• Filed: 04/28/1999
• Issued: 05/21/2002
• Est. Priority Date: 05/12/1997
• Status: Expired due to Term

• Current Assignee: Silicon Genesis
• Original Assignee: Silicon Genesis
• Inventors: Cheung, Nathan W., Henley, Francois J.
• Primary Examiner(s): Nelms, David
• Assistant Examiner(s): LE, DUNG ANH
• Application Number:
  US09/301,082
• Time in Patent Office: 1,119 Days
• Field of Search: 438/455, 438/456, 438/458, 438/691, 438/766, 438/798, 438/459, 438/977
• US Class Current: 438/455
• CPC Class Codes: B81C 1/0038 Processes for creating layers of materials not provided for in groups B81C1/00357 - B81C1/00373
• CPC Class Codes: B81C 2201/0191 Transfer of a layer from a carrier wafer to a device wafer
• CPC Class Codes: B81C 2201/0192 by cleaving the carrier wafer
• CPC Class Codes: H01L 21/187 by direct bonding
• 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 21/2236 from or into a plasma phase
• CPC Class Codes: H01L 21/26506 in group IV semiconductors
• CPC Class Codes: H01L 21/2658 of a molecular ion, e.g. decaborane
• CPC Class Codes: H01L 21/304 Mechanical treatment, e.g. grinding, polishing, cutting H01L21/30625 takes precedence
• CPC Class Codes: H01L 21/7624 using semiconductor on insulator [SOI] technology H01L21/76297 takes precedence; manufacture of integrated circuits on insulating substrates H01L21/84; silicon on sapphire [SOS] technology H01L21/86
• CPC Class Codes: H01L 21/76254 with separation/delamination along an ion implanted layer, e.g. Smart-cut, Unibond
• CPC Class Codes: H01L 21/7813 leaving a reusable substrate, e.g. epitaxial lift off
• CPC Class Codes: Y10S 117/915 Separating from substrate
• CPC Class Codes: Y10S 156/93 Semiconductive product delaminating, e.g. delaminating emiconductive wafer from underlayer
• CPC Class Codes: Y10S 438/974 Substrate surface preparation
• CPC Class Codes: Y10S 438/977 Thinning or removal of substrate
• CPC Class Codes: Y10T 156/11 Methods of delaminating, per se; i.e. , separating at bonding face
• CPC Class Codes: Y10T 156/1158 Electromagnetic radiation applied to work for delamination [e.g., microwave, uv, ir, etc.]
• CPC Class Codes: Y10T 156/19 Delaminating means
• CPC Class Codes: Y10T 428/21 Circular sheet or circular blank
• CPC Class Codes: Y10T 428/24893 : including particulate material
• CPC Class Codes: Y10T 428/249956 : Void-containing component is inorganic

Abstract

A technique for forming a film of material (12) from a donor substrate (10). The technique has a step of forming a weakened region in a selected manner at a selected depth (20) underneath the surface. An energy source is directed to a selected region of the donor substrate to initiate a controlled cleaving action of the substrate (10) at the selected depth (20), whereupon the cleaving action provides an expanding cleave front to free the donor material from a remaining portion of the donor substrate.

Claims

1. A process for forming a film of material from a substrate, said process comprising steps of:

forming a weakened region in a selected manner at a selected depth underneath said surface, to define a substrate material to be removed above said selected depth; and

providing energy to a selected region of said substrate to initiate a controlled cleaving action at said selected depth in said substrate by subjecting the substrate material to an initiation energy sufficient to fracture the material in the selected region but lower than a bulk material fracture energy of the substrate material to avoid uncontrolled cracking, whereupon said cleaving action is made using a propagating cleave front to free a portion of said material to be removed from said substrate.

2. The process of claim 1 wherein said step of providing energy comprises providing a propagation energy sufficient to sustain said controlled cleaving action after initiating the controlled cleaving action at the selected depth in the substrate to remove said material from said substrate to provide a film of material, the propagation energy being lower than the initiation energy.

3. The process of claim 1 wherein said step of providing energy increases a controlled stress in said material and sustains said controlled cleaving action to remove said material from said substrate to provide a film of material.

4. The process of claim 1 further comprising a step of providing additional energy to said substrate to sustain said controlled cleaving action to remove said material from said substrate to provide a film of material.

5. The process of claim 1 further comprising a step of providing additional energy to said substrate to increases a controlled stress in said material and sustains said controlled cleaving action to remove said material from said substrate to provide a film of material.

6. The process of claim 1 wherein said forming step creates damage selected from the group consisting of atomic bond damage, bond substitution, weakening, and breaking bonds of said substrate at said selected depth.

7. The process of claim 6 wherein said damage causes stress to said substrate material.

8. The process of claim 6 wherein said damage reduces an ability of said substrate material to withstand stress without a possibility of a cleaving of said substrate material.

9. The process of claim 1 wherein said propagating cleave front is selected from a single cleave front or multiple cleave fronts.

10. The process of claim 1 wherein said forming step causes stress of said material region at said selected depth by a presence of particles at said selected depth.

11. A process for forming a film of material from a substrate, the process comprising steps of:

forming a weakened region in a selected manner at a selected depth underneath the surface, to define a substrate material to be removed above the selected depth;

providing energy to a selected region of the substrate to initiate a controlled cleaving action at the selected depth in the substrate by subjecting the substrate material to a cleave front initiation energy sufficient to cause a cleave front of the material in the selected region; and

providing a cleave front propagation energy sufficient to sustain the controlled cleaving action after initiating the controlled cleaving action at the selected depth in the substrate to propagate the cleave front to free a portion of the material to be removed from the substrate, the cleave front propagation energy being lower than the cleave front initiation energy.

12. The process of claim 11 wherein the cleave front propagation energy is lower than the cleave front initiation energy by an amount equal to a cleave front stress energy.

13. The process of claim 11 wherein providing the cleave front propagation energy comprises directing the cleave front propagation energy in a selected direction which is higher than all other directions so as to propagate the cleave front along the selected direction.

14. The process of claim 11 wherein the propagating cleave front is selected from a single cleave front or multiple cleave fronts.

15. The process of claim 11 wherein forming the weakened region comprises causing stress of the material at the selected depth by a presence of particles at the selected depth.

16. A process for forming a film of material from a substrate, the process comprising steps of:

forming a weakened region in a selected manner at a selected depth underneath the surface, to define a substrate material to be removed above the selected depth;

providing energy to a selected region of the substrate to initiate a controlled cleaving action at the selected depth in the substrate by subjecting the substrate material to a cleave front initiation energy sufficient to cause a cleave front of the material in the selected region; and

providing a cleave front propagation energy sufficient to sustain the controlled cleaving action after initiating the controlled cleaving action at the selected depth in the substrate to propagate the cleave front to free a portion of the material to be removed from the substrate, wherein providing the cleave front propagation energy comprises directing the cleave front propagation energy in a selected direction which is higher than all other directions so as to propagate the cleave front along the selected direction.

17. The process of claim 16 wherein the cleave front propagation energy is lower than the cleave front initiation energy.

18. The process of claim 16 wherein the cleave front initiation energy is lower than a bulk material fracture energy of the substrate material to avoid uncontrolled cracking.

19. The process of claim 16 wherein the propagating cleave front is selected from a single cleave front or multiple cleave fronts.

20. The process of claim 16 wherein forming the weakened region comprises causing stress of the material at the selected depth by a presence of particles at the selected depth.