Ultra-thin semiconductors bonded on glass substrates

• US 7,273,788 B2
• Filed: 05/21/2003
• Issued: 09/25/2007
• Est. Priority Date: 05/21/2003
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Forbes, Leonard
• Primary Examiner(s): Nhu; David
• Application Number:
  US10/443,340
• Publication Number:
  US 20040232487A1
• Time in Patent Office: 1,588 Days
• Field of Search: 438/311, 438/106, 438/113, 438/197, 438/198, 438/199, 438/200, 438/201, 438/381, 438/471, 438/473, 438/474, 438/475, 438/766, 438/767, 438/770, 257/347
• US Class Current: 438/311
• 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 21/84 the substrate being other than a semiconductor body, e.g. being an insulating body
• CPC Class Codes: H01L 27/1203 the substrate comprising an insulating body on a semiconductor body, e.g. SOI three-dimensional layout H01L27/0688
• CPC Class Codes: H01L 29/66772 Monocristalline silicon transistors on insulating substrates, e.g. quartz substrates H01L29/66666 takes precedence; thin film FinFETs H01L29/66795
• CPC Class Codes: H01L 29/78603 characterised by the insulating substrate or support H01L29/78657 takes precedence
• CPC Class Codes: H01L 29/78606 with supplementary region or layer in the thin film or in the insulated bulk substrate supporting it for controlling or increasing the safety of the device H01L29/78642, H01L29/78645 take precedence
• CPC Class Codes: H01L 29/78654 Monocrystalline silicon transistors
• CPC Class Codes: H01L 29/78657 SOS transistors

Abstract

A method for forming a semiconductor on insulator structure includes providing a glass substrate, providing a semiconductor wafer, and performing a bonding cut process on the semiconductor wafer and the glass substrate to provide a thin semiconductor layer bonded to the glass substrate. The thin semiconductor layer is formed to a thickness such that it does not yield due to temperature-induced strain at device processing temperatures. An ultra-thin silicon layer bonded to a glass substrate, selected from a group consisting of a fused silica substrate, a fused quartz substrate, and a borosilicate glass substrate, provides a silicon on insulator wafer in which circuitry for electronic devices is fabricated.

Claims

1. A method for forming an electronic device comprising:

bonding a semiconductor layer to a glass substrate, the semiconductor layer having a thickness of less than 0.1 μ

m such that the semiconductor layer does not yield due to temperature-induced strain at device processing temperatures; and

forming circuitry in the semiconductor layer.

2. The method of claim 1, wherein bonding a semiconductor layer to a glass substrate includes bonding a semiconductor layer to a fused silica substrate, a fused quartz substrate, or a borosilicate glass substrate.

3. The method of claim 1, wherein bonding a semiconductor layer to a glass substrate includes thermal processing using plasma enhanced bonding.

4. A method for forming an electronic device comprising:

implanting ions into a silicon wafer;

attaching the silicon wafer to a glass substrate forming an attached structure;

thermally processing the silicon wafer attached to the glass substrate to cut a portion of the silicon wafer from the attached structure;

processing the attached structure to provide a silicon layer having a thickness of less than 0.1 microns; and

forming circuitry in a silicon layer.

5. The method of claim 4, wherein attaching the silicon wafer to a glass substrate includes attaching the silicon wafer to a fused silica substrate, a fused quartz substrate, or a borosilicate glass substrate.

6. The method of claim 4, wherein forming circuitry in the silicon layer includes forming fully depleted devices using CMOS device technology.

7. The method of claim 4, wherein forming circuitry in the silicon layer includes patterning the silicon layer by trench isolation in a partially depleted CMOS process.

8. A method for forming an electronic device comprising:

performing a bonding cut process on a silicon wafer and a glass substrate to provide a silicon layer bonded to the glass substrate, the silicon layer having a thickness such that the silicon layer does not yield due to temperature-induced strain at device processing temperatures; and

forming circuitry in the silicon layer.

9. The method of claim 8, wherein performing a bonding cut process on a silicon wafer and a glass substrate includes performing a bonding cut process on a silicon wafer and a fused silica substrate, a fused quartz substrate, and a borosilicate glass substrate.

10. The method of claim 8, wherein performing a bonding cut process on a silicon wafer and a glass substrate includes providing a glass sheet that has been polished and cutting the glass sheet into a wafer size pattern to form the glass substrate.

11. The method of claim 8, wherein performing a bonding cut process on a silicon wafer and a glass substrate includes bonding the silicon wafer to the glass substrate by plasma enhanced bonding to cut the silicon wafer.

12. The method of claim 8, wherein performing a bonding cut process on a silicon wafer and a glass substrate includes bonding the silicon wafer to the glass substrate at a temperature ranging from about 400°

C. to 600°

C. to cut the silicon wafer providing an intermediate silicon layer bonded to the glass substrate.

13. The method of claim 8, wherein performing a bonding cut process on a silicon wafer and a glass substrate includes bonding the silicon wafer to the glass substrate to cut the silicon wafer providing an intermediate silicon layer bonded to the glass substrate and subjecting the intermediate silicon layer bonded to the glass substrate to temperatures ranging from 800°

C. to 1000°

C.

14. The method of claim 8, wherein performing a bonding cut process on a silicon wafer and a glass substrate includes bonding the silicon wafer to the glass substrate to cut the silicon wafer providing an intermediate silicon layer bonded to the glass substrate and annealing the intermediate silicon layer bonded to the glass substrate by laser assisted annealing.

15. The method of claim 8, wherein performing a bonding cut process on a silicon wafer and a glass substrate to provide a silicon layer includes polishing an intermediate silicon layer formed by the bonding cut process.

16. The method of claim 15, wherein polishing an intermediate silicon layer formed by the bonding cut process includes polishing the intermediate silicon layer to provide the silicon layer having a thickness of about 0.1 microns.

17. The method of claim 15, wherein polishing an intermediate silicon formed by the bonding cut process includes polishing the intermediate silicon layer to provide the silicon layer having a thickness of less than 0.1 microns.

18. The method of claim 8, wherein forming circuitry in the silicon layer includes forming fully depleted devices using CMOS device technology.

19. The method of claim 8, wherein forming circuitry in the silicon layer includes patterning the silicon layer by trench isolation in a partially depleted CMOS process.

20. The method of claim 19, wherein patterning the silicon layer by trench isolation in a partially depleted CMOS process includes performing the partially depleted CMOS process for devices with floating bodies.

21. A method for fabricating a transistor comprising:

providing a semiconductor on insulator structure formed by a method including;

conditioning a semiconductor wafer; and

performing a bonding cut process on a semiconductor wafer and a glass substrate to provide a semiconductor layer, from the semiconductor wafer, bonded to the glass substrate, the semiconductor layer having a thickness such that the semiconductor layer does not yield due to temperature-induced strain at device processing temperatures; and

forming a transistor in the semiconductor on insulator structure.

22. The method of claim 21, wherein performing a bonding cut process on a semiconductor wafer and a glass substrate to provide a semiconductor layer bonded to the glass substrate includes performing a bonding cut process on a semiconductor wafer and a fused silica substrate, a fused quartz substrate, or a borosilicate glass substrate.

23. The method of claim 21, wherein performing a bonding cut process on a semiconductor wafer and a glass substrate to provide a semiconductor layer bonded to the glass substrate includes polishing an intermediate semiconductor layer provided by the bonding cut to thin the intermediate semiconductor layer.

24. The method of claim 21, wherein conditioning a semiconductor wafer includes forming an insulator layer on a surface of the semiconductor wafer.

25. A method for fabricating a memory device comprising:

providing a silicon on insulator structure formed by a method including;

conditioning a silicon wafer; and

performing a bonding cut process on the silicon wafer and a glass substrate to provide a silicon layer bonded to the glass substrate, the silicon layer having a thickness of about 0.1 microns; and

forming a memory circuit in the silicon on insulator structure.

26. The method of claim 25, wherein performing a bonding cut process on the silicon wafer and a glass substrate includes performing a bonding cut process on the silicon wafer and a glass substrate, the glass substrate selected from a group consisting of fused silica, fused quartz, and a borosilicate glass.

27. The method of claim 25, wherein performing a bonding cut process on the silicon wafer and a glass substrate to provide a silicon layer bonded to the glass substrate includes polishing an intermediate semiconductor layer provided by the bonding cut to thin the intermediate semiconductor layer.

28. The method of claim 25, wherein conditioning a silicon wafer includes providing a silicon wafer having a silicon oxide layer on a surface of the silicon wafer.

29. The method of claim 25, wherein conditioning a silicon wafer includes providing implanting hydrogen ions into the silicon wafer.

30. A method for manufacturing an electronic system comprising:

providing a processor; and

coupling a memory device to the processor, the memory device formed by a method including;

providing a silicon on insulator structure formed by a method including;

providing a glass substrate;

performing a bonding cut process on a silicon wafer and the glass substrate to provide a silicon layer bonded to the glass substrate, the silicon layer having a thickness such that the silicon layer does not yield due to temperature-induced strain at device processing temperatures; and

forming a memory circuit in the silicon on insulator structure.

31. The method of claim 30, wherein providing a glass substrate includes providing a substrate of glass material selected from a group consisting of fused silica, fused quartz, and a borosilicate glass.

32. The method of claim 30, wherein performing a bonding cut process on a silicon wafer and the glass substrate includes performing a bonding cut process on a silicon wafer having an insulator formed on a surface of the silicon wafer.

33. The method of claim 30, wherein performing a bonding cut process on the silicon wafer and the glass substrate to provide a silicon layer bonded to the glass substrate includes polishing an intermediate silicon layer provided by the bonding cut to provide the silicon layer having a thickness of about 0.1 microns.

34. The method of claim 30, wherein performing a bonding cut process on the silicon wafer and the glass substrate to provide a silicon layer bonded to the glass substrate includes polishing an intermediate silicon layer provided by the bonding cut to provide the silicon layer having a thickness of less than 0.1 microns.