Method and apparatus for cutting a semiconductor wafer

• US 20010040152A1
• Filed: 05/02/2001
• Published: 11/15/2001
• Est. Priority Date: 05/09/2000
• Status: Active Grant

• Current Assignee: Shinko Electric Industries Company Limited (Fujitsu Limited)
• Original Assignee: Shinko Electric Industries Company Limited (Fujitsu Limited)
• Inventors: Higashi, Mitsutoshi, Sakaguchi, Hideaki
• Granted Patent: US 6,583,383 B2
• Time in Patent Office: Days
• US Class Current: 219/121.72
• CPC Class Codes: B23K 26/146 the fluid stream containing a liquid
• CPC Class Codes: B23K 26/18 using absorbing layers on the workpiece, e.g. for marking or protecting purposes
• 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

Abstract

A method for cutting a semiconductor wafer is provided. A mount tape is adhered to a back surface of the semiconductor wafer. The mount tape comprises a resin base and a mesh-like member made of a material harder than that of the resin base and embedded in the resin base. A beam-like liquid jet is ejected toward a front surface of the semiconductor wafer and, simultaneously, a laser beam is transmitted axially through said beam-like liquid jet, so that the semiconductor wafer is cut into individual pieces, by said laser beam, together with the resin base of the mount tape, while the mesh-like member is not cut, but remains in its connected state.

Claims

1. A method for cutting a semiconductor wafer, said method comprising the following steps of:

adhering a mount tape on a back surface of said semiconductor wafer, said mount tape comprising a resin base and a mesh-like member made of a material harder than that of said resin base and embedded in said resin base; and

ejecting a beam-like liquid jet toward a front surface of said semiconductor wafer and simultaneously transmitting a laser beam axially through said beam-like liquid jet, so that said semiconductor wafer is cut into individual pieces by said laser beam together with said resin base of the mount tape, while said mesh-like member remains in its connected state.

2. A method as set forth in

claim 1

, wherein said beam-like liquid jet is a pressurized pure water jet and is focused so as to have a diameter in a range of 30 to 50 μ

m, so that said semiconductor wafer is cut along a slit having a corresponding width.

3. A method as set forth in

claim 1

, wherein said mesh-like member is a glass cloth made of glass filaments.

4. A method as set forth in

claim 3

, wherein said glass cloth comprises a plurality of lateral filaments and a plurality of transverse filaments extending substantially perpendicularly to the lateral filaments, so that said semiconductor wafer is cut along a slit which extends so as not to be in parallel to said lateral and said transverse filaments.

5. A method as set forth in

claim 4

, wherein said semiconductor wafer is cut along a slit which extends at an angle of 30 to 60 degree to said lateral and said transverse filaments.

6. A method as set forth in

claim 2

, wherein a total thickness of said mount tape is in a range from 80 to 100 μ

m and a diameter of said glass fiber is in a range from 20 to 90 μ

m.

7. A method as set forth in

claim 1

, wherein a pressure of said beam-like liquid jet and an output of said laser beam is determined in such a manner that said semiconductor wafer is sufficiently cut, while the mesh-like member of the mount tape is not cut, but remains in its connected state.

8. An apparatus for cutting a semiconductor wafer comprising:

a mount tape comprising a resin base and a mesh-like member made of a material harder than that of said resin base and embedded in said resin base;

first means for holding said mount tape, to which a back surface of said the semiconductor wafer is adhered,

second means for ejecting a beam-like liquid jet toward a front surface of said semiconductor wafer and simultaneously transmitting a laser beam axially through said beam-like liquid jet;

means for moving at least one of said first and second means, so that said semiconductor wafer is cut into individual pieces by said laser beam, together with said resin base of the mount tape, while said mesh-like member remains in its connected state.