Method of producing laser-processed product and adhesive sheet, for laser processing used therefor

Abstract

A manufacturing method of laser processed parts is characterized in that at least a pressure-sensitive adhesive layer is provided on a base material as a pressure-sensitive adhesive sheet ( 2 ) for laser processing, using a material having specified physical properties, and this method comprises a step of adhering the pressure-sensitive adhesive sheet ( 2 ) for laser processing to the laser beam exit side of the work ( 1 ) by way of the pressure-sensitive adhesive layer, a step of processing the work by irradiating the work with a laser beam ( 6 ) of within 2 times of the irradiation intensity for forming a through-hole in the work ( 1 ), at higher than the irradiation intensity of threshold for inducing ablation of the work ( 1 ), and a step of peeling the pressure-sensitive adhesive sheet ( 2 ) for laser processing from the work ( 1 ) after the machining. Therefore, contamination of the work surface by decomposition products can be effectively suppressed, and laser processed parts can be manufactured easily and at high production efficiency.

1 . The manufacturing method according to  claim 30 , 
 wherein the sheet (i) is selected as the pressure-sensitive adhesive sheet.    
   
   
       2 . The manufacturing method according to  claim 31 , 
 wherein the sheet (I) is selected as the pressure-sensitive adhesive sheet.    
   
   
       3 . The manufacturing method according to  claim 30 , 
 wherein the sheet (ii) is selected as the pressure-sensitive adhesive sheet.    
   
   
       4 . The manufacturing method according to  claim 31 , 
 wherein the sheet (II) is selected as the pressure-sensitive adhesive sheet.    
   
   
       5 . The manufacturing method according to  claim 30 , 
 wherein the sheet (iii) is selected as the pressure-sensitive adhesive sheet.    
   
   
       6 . The manufacturing method according to  claim 31 , 
 wherein the sheet (III) is selected as the pressure-sensitive adhesive sheet.    
   
   
       7 . The manufacturing method according to  claim 30 , 
 wherein the sheet (iv) is selected as the pressure-sensitive adhesive sheet.    
   
   
       8 . The manufacturing method according to  claim 31 , 
 wherein the sheet (IV) is selected as the pressure-sensitive adhesive sheet.    
   
   
       9 . The manufacturing method according to  claim 30 , 
 wherein the sheet (v) is selected as the pressure-sensitive adhesive sheet.    
   
   
       10 . The manufacturing method according to  claim 31 , 
 wherein the sheet (V) is selected as the pressure-sensitive adhesive sheet.    
   
   
       11 . The manufacturing method according to  claim 30 , 
 wherein the sheet (vi) is selected as the pressure-sensitive adhesive sheet.    
   
   
       12 . The manufacturing method according to  claim 30 , 
 wherein the sheet (vii) is selected as the pressure-sensitive adhesive sheet.    
   
   
       13 . The manufacturing method according to  claim 3 , wherein said work is any one of sheet materials, circuit boards, semiconductor wafers, glass substrates, ceramic substrates, metal substrates, semiconductor laser or other light emitting or receiving element substrates, MEMS substrates, semiconductor packages, cloth, leather, or paper.  
   
   
       14 . The manufacturing method according to  claim 2 , wherein said work is either semiconductor wafer or metal substrate.  
   
   
       15 . The manufacturing method according to  claim 5 , wherein said base material contains polyolefin resin.  
   
   
       16 . The manufacturing method according to  claim 9 , wherein said work is a sheet material.  
   
   
       17 . The manufacturing method according to  claim 1 , wherein the step of processing the work comprising cutting or piercing the work.  
   
   
       18 . (canceled)  
   
   
       19 . A pressure-sensitive adhesive sheet for laser processing a work, comprising: 
 a base material; and    at least a pressure-sensitive adhesive layer provided on the base material, wherein the pressure-sensitive adhesive sheet has a ratio of etching (etching rate/energy fluence) of the base material which is 0.4 [(μm/pulse)/(J/cm 2 )] or less.    
   
   
       20 . The pressure-sensitive adhesive sheet for laser processing according to  claim 19 , wherein said base material contains polyolefin resin.  
   
   
       21 . The pressure-sensitive adhesive sheet for laser processing according to  claim 20 , wherein said polyolefin resin is polyethylene.  
   
   
       22 . The pressure-sensitive adhesive sheet for laser processing according to  claim 20 , wherein said a functional group of the side chain of the polyolefin resin has connected with the main chain by methylene combination.  
   
   
       23 . The pressure-sensitive adhesive sheet for laser processing according to  claim 20 , wherein said a functional group of the side chain of the polyolefin resin has connected with the main chain by ether combination.  
   
   
       24 . The pressure-sensitive adhesive sheet for laser processing according to  claim 19 , wherein said base material contains polynorbornene resin.  
   
   
       25 . The pressure-sensitive adhesive sheet for laser processing according to  claim 19 , wherein said base material contains polyurethane resin.  
   
   
       26 . The pressure-sensitive adhesive sheet for laser processing according to  claim 19 , wherein said base material contains polyalkyleneglycol resin.  
   
   
       27 . A method of manufacturing laser processed parts comprising: 
 attaching the pressure-sensitive adhesive sheet of claims  19 , to a work on a laser beam exit side via the pressure-sensitive adhesive layer,    processing the work by irradiating the work with a laser beam, and    peeling the pressure-sensitive adhesive sheet from the processed work.    
   
   
       28 . The manufacturing method of laser processed parts according to  claim 27 , wherein said work is any one of sheet materials, circuit boards, semiconductor wafers, glass substrates, ceramic substrates, metal substrates, semiconductor laser or other light emitting or receiving element substrates, MEMS substrates, semiconductor packages, cloth, leather, or paper.  
   
   
       29 . The manufacturing method of laser processed parts according to  claim 27 , wherein the step of processing the work is a step of cutting or piercing the work.  
   
   
       30 . A method of manufacturing laser processed parts comprising: 
 providing a pressure-sensitive adhesive sheet for laser processing comprising a base material and a pressure-sensitive adhesive layer formed thereon, said pressure-sensitive adhesive sheet being selected from the group consisting of: 
 (i) a sheet having ratio of light absorption coefficient expressed in formula (1) which is less than 1:  
   Ratio of light absorption coefficient=(absorption coefficient of pressure-sensitive adhesive sheet for laser processing in light of wavelength of 355 nm)/(absorption coefficient of work in light of wavelength of 355 nm)  (1);  
 (ii) a sheet having a refractive index which is smaller than that of the work;  
 (iii) a sheet having a ratio of density expressed in formula (2) which is less than 1:  
   Ratio of density=(density of pressure-sensitive adhesive sheet for laser processing)/(density of work)  (2);  
 (iv) a sheet having a ratio of tensile strength expressed in formula (3) which is less than 1:  
   Ratio of tensile strength=(tensile strength of pressure-sensitive adhesive sheet for laser processing)/(tensile strength of work)  (3);  
 (v) a sheet having a ratio of total coupling energy expressed in formula (4) which is 1 or more:  
   Ratio of total coupling energy=(total coupling energy  A  of minimum value out of the total of coupling energy of one carbon atom in the resin component composing the base material and other atom coupling to this carbon atom/total coupling energy  B  of minimum value out of the total of coupling energy of one carbon atom in the material component composing the work to be used and other atom coupling to this carbon atom)  (4);  
 (vi) a sheet having a ratio of specific heat expressed in formula (5) which is 1 or more:  
   Ratio of specific heat=(specific heat of pressure-sensitive adhesive sheet for laser processing)/(specific heat of work)  (5); and  
 (vii) a sheet having transmissivity in an absorption region of laser beam of 50% or more;  
   attaching the pressure-sensitive adhesive sheet to a work on a laser beam exit side via the pressure-sensitive adhesive layer;    processing the work by irradiating the work with a laser beam of wavelength in ultraviolet region or a laser beam capable of absorbing the light in ultraviolet region passing through multiple-photon absorbing process, said laser beam having an irradiation intensity which is higher than that of threshold for inducing ablation of the work but no more than 2 times greater than that for forming a through-hole in the work; and    peeling the pressure-sensitive adhesive sheet from the processed work.    
   
   
       31 . A method of manufacturing laser processed parts comprising: 
 providing a pressure-sensitive adhesive sheet for laser processing comprising a base material and a pressure-sensitive adhesive layer formed thereon, said pressure-sensitive adhesive sheet being selected from the group consisting of: 
 (I) a sheet having an absorption coefficient of laser beam of wavelength of 355 nm which is less than 20 cm −1 ;  
 (II) a sheet having a refractive index which is less than 1.53;  
 (III) a sheet having a density which is less than 1.1 g/cm 3  and having a ratio of density expressed in formula (2) which is less than 1:  
   Ratio of density=(density of pressure-sensitive adhesive sheet for laser processing)/(density of the work)  (2);  
 (IV) a sheet having a tensile strength which is less than 100 MPa; and  
 (V) a sheet having a minimum value of group parameters of coupling energy for coupling carbon atoms composing the base material and directly coupling atoms, which is 800 kJ/mol or more;  
   attaching the pressure-sensitive adhesive sheet to a work made of a metal material on a laser beam exit side via the pressure-sensitive adhesive layer;    processing the work by irradiating the work with a laser beam of wavelength in ultraviolet region or a laser beam capable of absorbing the light in ultraviolet region passing through multiple-photon absorbing process, said laser beam having an irradiation intensity which is higher than that of threshold for inducing ablation of the work but no more than 2 times greater than that for forming a through-hole in the work; and    peeling the pressure-sensitive adhesive sheet from the processed work.    
   
   
       32 . The method according to  claim 6 , wherein said base material contains polyolefin resin.