Treatment method of cleaved film for the manufacture of substrates

• US 6,171,965 B1
• Filed: 04/21/1999
• Issued: 01/09/2001
• Est. Priority Date: 04/21/1999
• Status: Expired due to Term

• Current Assignee: Silicon Genesis
• Original Assignee: Silicon Genesis
• Inventors: Kang, Sien G., Malik, Igor J.
• Primary Examiner(s): Monin, Jr., Donald L.
• Assistant Examiner(s): RAO, SHRINIVAS H
• Application Number:
  US09/295,858
• Time in Patent Office: 629 Days
• Field of Search: 438/458, 438/977, 438/734, 438/766, 438/795, 438/715, 438/711, 438/695, 438/706, 216/63, 216/94-109, 216/83, 216/38, 216/52, 216/56, 216/67, 216/69, 148/DIG.12
• US Class Current: 438/695
• CPC Class Codes: H01L 21/304 Mechanical treatment, e.g. grinding, polishing, cutting H01L21/30625 takes precedence
• CPC Class Codes: H01L 21/3065 Plasma etching; Reactive-ion etching
• CPC Class Codes: H01L 21/76254 with separation/delamination along an ion implanted layer, e.g. Smart-cut, Unibond
• CPC Class Codes: H01L 21/76259 with separation/delamination along a porous layer
• CPC Class Codes: Y10S 148/012 Bonding, e.g. electrostatic for strain gauges

Abstract

A method for treating a film of material, which can be defined on a substrate, e.g., silicon. The method includes providing a substrate comprising a cleaved surface, which is characterized by a predetermined surface roughness value. The substrate also has a distribution of hydrogen bearing particles defined from the cleaved surface to a region underlying said cleaved surface. The method also includes increasing a temperature of the cleaved surface to greater than about 1,000 Degrees Celsius while maintaining the cleaved surface in a etchant bearing environment to reduce the predetermined surface roughness value by about fifty percent and greater. Preferably, the value can be reduced by about eighty or ninety percent and greater, depending upon the embodiment.

Claims

1. A method of fabricating a substrate, said method comprising:

providing a donor substrate comprising an upper surface;

introducing a plurality of particles through said upper surface and into said donor substrate to a selected depth beneath said upper surface to form a thickness of material of said donor substrate from said upper surface to said selected depth, said plurality of particles being defined by a distribution along said selected depth;

introducing energy to said donor substrate to initiate a cleaving action to free said thickness of material from said donor substrate to form a cleaved surface from said donor substrate, said cleaved surface comprising a surface roughness of a predetermined value and comprising a portion of said distribution of said plurality of particles; and

applying a combination of thermal treatment and an etchant to said cleaved surface after forming said cleaved surface and said portion of said distribution of said plurality of particles to reduce said surface roughness of said predetermined value, wherein said etchant comprises a halogen bearing compound selected from at least any one of Cl₂, HCl, HBr, HI, and HF.

2. The method of claim 1 wherein said thermal treatment increases a temperature of said cleaved surface to about 1,000 Degrees Celsius and greater.

3. The method of claim 2 wherein said temperature increases is about 10 Degrees Celsius per second and greater.

4. The method of claim 2 wherein said temperature increases is about 20 Degrees Celsius per second and greater.

5. The method of claim 1 wherein said plurality of particles comprise a hydrogen bearing species.

6. The method of claim 1 wherein said plurality of particles are derived from hydrogen gas.

7. The method of claim 1 wherein said predetermined value is greater than about two nanometers root mean square.

8. The method of claim 1 wherein said reduced predetermined value is less than about 1 nanometers root mean square.

9. The method of claim 1 wherein said reduced predetermined value is less than about 0.1 nanometer root mean square.

10. The method of claim 1 wherein said etchant comprises a hydrogen bearing compound.

16. The method of claim 1, further comprising

depositing a material over said surface of said substrate, wherein said thermal-treatment step, said etching step, and said depositing step are performed simultaneously for a particular time.

11. A method of fabricating a substrate, said method comprising:

providing a silicon substrate comprising an upper surface;

introducing a plurality of particles through said upper surface and into said donor substrate to a selected depth beneath said upper surface to form a thickness of material of said donor substrate from said upper surface to said selected depth, said plurality of particles being defined by a distribution along said selected depth;

introducing energy to said donor substrate to initiate a cleaving action to free said thickness of material from said donor substrate to form a cleaved surface from said donor substrate, said cleaved surface comprising a surface roughness of a predetermined value and comprising a portion of said distribution of said plurality of particles; and

applying a combination of thermal treatment using rapid thermal processing and an etchant comprising a hydrogen bearing compound to said cleaved surface formed by said introducing-energy step and said portion of said distribution of said plurality of particles to reduce said surface roughness of said predetermined value, said etchant comprises a halogen hewing compound selected from at least any one of Cl₂, HCl, HBr, HI, and HF.

12. The method of claim 11 wherein the energy is provided by a pressurized fluid.

13. The method of claim 11 wherein said applying further comprising applying a film to said cleaved surface.

14. The method of claim 13 wherein said film is provided by chemical vapor deposition.

15. The method of claim 11 wherein said thermal treatment increases a temperature of said surface at a rate of greater than 10 Degrees Celsius/second and greater.

17. A method of fabricating a substrate, said method comprising:

providing a donor substrate;

introducing a plurality of particles of first type into said donor substrate to a selected depth beneath a surface of said donor substrate to define a thickness of material of said donor substrate from said surface to said selected depth, said plurality of particles being defined by a distribution along said selected depth;

introducing energy to said donor substrate to initiate a cleaving action to free said thickness of material from said donor substrate to define a cleaved surface from said donor substrate, said cleaved surface comprising a surface roughness of a particular value and comprising a portion of said distribution of said plurality of particles;

treating said thickness of material to introduce a plurality of particles of second type into said thickness of material; and

applying a thermal treatment and contacting an etchant to said cleaved surface and said portion of said distribution of said plurality of particles to reduce said surface roughness of said particular value, wherein said etchant is a halogen bearing compound selected from at least any one of Cl₂, HCl, HBr, HI, and HF.

18. The method of claim 17 wherein said plurality of particles of first type and said plurality of particles of second type are the same.

19. The method of claim 18 wherein said plurality of particles of first type and said plurality of particles of second type both include hydrogen.

20. The method of claim 18 wherein said treating step is performed to increase the concentration of said plurality of particles in said thickness of material.