METHOD FOR MANUFACTURING THIN SUBSTRATE USING A LAMINATE BODY

• US 20090115075A1
• Filed: 12/17/2008
• Published: 05/07/2009
• Est. Priority Date: 07/14/2006
• Status: Active Grant

• Current Assignee: Carl R. Kessel, Larry D. Boardman, Richard J. Webb
• Original Assignee: Carl R. Kessel, Larry D. Boardman, Richard J. Webb
• Inventors: KESSEL, Carl R., Webb, Richard J., Boardman, Larry D.
• Granted Patent: US 7,759,050 B2
• Time in Patent Office: Days
• US Class Current: 257/787
• CPC Class Codes: B24B 7/228 for grinding thin, brittle parts, e.g. semiconductors, wafers grinding edges of thin, brittle parts B24B9/065
• CPC Class Codes: B32B 2310/0806 using electromagnetic radiation
• CPC Class Codes: B32B 2457/14 Semiconductor wafers
• CPC Class Codes: B32B 37/12 characterised by using adhesives
• CPC Class Codes: H01L 21/6835 using temporarily an auxiliary support
• CPC Class Codes: H01L 21/6836 Wafer tapes, e.g. grinding or dicing support tapes adhesive tapes in general C09J7/20
• CPC Class Codes: H01L 2221/68327 used during dicing or grinding
• CPC Class Codes: H01L 2221/68381 Details of chemical or physical process used for separating the auxiliary support from a device or wafer
• CPC Class Codes: H01L 2221/68386 Separation by peeling
• CPC Class Codes: Y10T 428/31663 As siloxane, silicone or silane

Abstract

Provided is a laminated body comprising a substrate to be ground and a support, where the substrate may be ground to a very small (thin) thickness and can then be separated from the support without damaging the substrate. One embodiment is a laminated body comprising a substrate to be ground, a curable silicone adhesive layer in contact with the substrate to be ground, a photothermal conversion layer comprising a light absorbing agent and a heat decomposable resin, and a light transmitting support. After grinding the substrate surface which is opposite that in contact with the adhesive layer, the laminated body is irradiated through the light transmitting layer and the photothermal conversion layer decomposes to separate the substrate and the light transmitting support.

Claims

1. A method of providing a thin substrate comprising:

providing a laminated body comprising

a substrate to be ground;

a joining layer comprising a cured silicone in contact with said substrate;

a photothermal conversion layer comprising a light absorbing agent and a heat decomposable resin disposed beneath the joining layer; and

a light transmitting support disposed beneath the photothermal conversion layer;

grinding the face of said substrate to a desired thickness to form a ground semiconductor wafer;

irradiating radiation energy through said light-transmitting support side to decompose said photothermal conversion layer, thereby causing separation into a thin substrate having said adhesive layer and a light-transmitting support; and

optionally

removing said cured silicone joining layer from said ground substrate.

2. A method according to claim 1, wherein providing a laminated body further comprises:

applying a photothermal conversion layer comprising a light-absorbing agent and a heat decomposable resin on a light-transmitting support;

preparing a semiconductor wafer having a circuit face with a circuit pattern and a non-circuit face on the side opposite of said circuit face;

laminating said semiconductor wafer and said light-transmitting support through a curable silicone adhesive by placing said circuit face and said photothermal conversion layer to face each other; and

irradiating light through said light-transmitting support side to cure the curable silicone adhesive layer, thereby forming a laminated body having a non-circuit face on the outside surface.

3. A method according to claim 2, wherein laminating said semiconductor wafer and said light-transmitting support through a curable silicone adhesive is performed in a vacuum.

4. A method according to claim 1, wherein the ground semiconductor wafer is ground to a thickness of 50 μ

m or less.

5. A method according to claim 1, wherein the ground semiconductor wafer has been partially sawn through on the circuit face.

6. A method according to claim 1, further comprising dicing the ground semiconductor wafer to cut it into a plurality of ground semiconductor chips.

7. A method according to claim 6, wherein a die bonding tape is affixed to the semiconductor wafer before dicing the ground semiconductor wafer.

8. A method according to claim 2, wherein the ground semiconductor wafer is ground to a thickness of 50 μ

m or less.

9. A method according to claim 2, wherein the ground semiconductor wafer has been partially sawn through on the circuit face.

10. A method according to claim 2, further comprising dicing the ground semiconductor wafer to cut it into a plurality of ground semiconductor chips.

11. A method according to claim 10, wherein a die bonding tape is affixed to the semiconductor wafer before dicing the ground semiconductor wafer.

12. A method according to claim 1, wherein the substrate to be ground comprises a semiconductor wafer, said wafer having a circuit face adjacent said joining layer and a non-circuit face.

13. A method according to claim 2, wherein the substrate to be ground comprises a semiconductor wafer, said wafer having a circuit face adjacent said joining layer and a non-circuit face.

14. A laminated body made according to the method of claim 2.

15. A laminated body comprising:

a substrate to be ground;

a curable silicone adhesive joining layer in contact with said substrate;

a photothermal conversion layer comprising a light absorbing agent and a heat decomposable resin disposed beneath the joining layer; and

a light transmitting support disposed beneath the photothermal conversion layer.