Stack structure cutting method and stack structure

• US 7,838,796 B2
• Filed: 02/10/2005
• Issued: 11/23/2010
• Est. Priority Date: 11/29/2004
• Status: Expired due to Fees

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Furui, Toshikazu
• Primary Examiner(s): Heinrich; Samuel M
• Application Number:
  US11/053,888
• Publication Number:
  US 20060113286A1
• Time in Patent Office: 2,112 Days
• Field of Search: 21912167-12169, 219/121.72, 219/121.84, 438/113, 438/114, 438/463, 438/465, 156/257, 156/267, 156/344
• US Class Current: 219/121.72
• CPC Class Codes: B23K 2101/40 Semiconductor devices
• CPC Class Codes: B23K 2103/50 Inorganic material, e.g. metals, not provided for in B23K2103/02 – B23K2103/26
• CPC Class Codes: B23K 26/0853 Devices involving movement of the workpiece in at least in two axial directions, e.g. in a plane
• CPC Class Codes: B23K 26/123 in an atmosphere of particular gases
• CPC Class Codes: B23K 26/142 for the removal of by-products
• CPC Class Codes: B23K 26/18 using absorbing layers on the workpiece, e.g. for marking or protecting purposes
• CPC Class Codes: B23K 26/38 by boring or cutting
• CPC Class Codes: B23K 26/40 taking account of the properties of the material involved

Abstract

A method of cutting a stack structure and the stack structure are disclosed. In the stack structure comprising at least one laser absorbing member and at least one laser transmitting member, a plurality of grooves are formed on the surface of the laser transmitting member which is in contact with the laser absorbing member, which grooves correspond to a plurality off cutting lines. In order to cut this stack structure, a laser beam is emitted on the laser absorbing member along each of the cutting lines, while at the same time gas is injected at the laser irradiated spot.

Claims

1. A method of cutting a stack structure, comprising:

forming a stack structure by stacking at least first and second laser transmitting members and at least one laser absorbing member, each of the first and second laser transmitting members having a plurality of grooves on a surface, the laser absorbing member having two surfaces, each of the surfaces respectively contacting the surface of the first laser transmitting member and the surface of the second laser transmitting member, and covering the plurality of grooves;

emitting a laser beam on the surface of the laser absorbing member through the groove of the first laser transmitting member, the laser beam scattering material of the laser absorbing member in the groove;

injecting gas at a laser-irradiated spot on the first laser transmitting member;

cutting the laser absorbing member by the emitted laser beam and cutting the first laser transmitting member by the scattering material;

carrying the scattered material into the groove of the second laser transmitting member by the injected gas through gaps formed by cutting the first laser transmitting member and the laser absorbing member; and

cutting the second laser transmitting member by the scattered material in the groove of the second laser transmitting member.

2. A method of cutting a stack structure according to claim 1,

wherein the number of the laser transmitting members is larger than the number of the laser absorbing members by one.

3. A method of cutting a stack structure according to claim 1,

wherein the stack structure has not less than four members and the number of the laser transmitting members is the same as the number of the laser absorbing members.

4. A method of cutting a stack structure according to claim 1,

wherein the gas is selected such that the product formed by reacting the gas with the laser absorbing member is a laser absorbing material.

5. A method of cutting a stack structure according to claim 4,

wherein the gas is a selected one of N₂ gas and an inert gas.

6. A method of cutting a stack structure according to claim 1, further comprising moving the stack structure along cutting lines.

7. A method of cutting a stack structure, comprising:

stacking a first and a second laser transmitting member and a laser absorbing member, each of the first and second laser transmitting members having a groove on a surface, the laser absorbing member having two surfaces, each of the surfaces respectively contacting the two surface of the first laser transmitting member and the surface of the second laser transmitting member, and covering the groove;

emitting a laser beam on the surface of the absorbing member through the groove of the first laser transmitting member, the laser beam scattering material of the laser absorbing member in the groove contacting the surface of the first laser transmitting member;

injecting gas at a laser-irradiated spot on the first laser transmitting member;

cutting the laser absorbing member by the emitted laser beam and cutting the first laser transmitting member by the scattered material;

carrying the scattered material into the groove of the second laser transmitting member by the injected gas through gaps formed by cutting the first laser transmitting member and the laser absorbing member; and

cutting the second laser transmitting member by the scattered material in the groove of the second laser transmitting member.