Manufacturing method of processed resin substrate and laser processing apparatus

Abstract

A manufacturing method of a processed resin substrate includes: preparing a resin substrate including a resin layer and a metal layer that covers at least a part of one surface of the resin layer; and forming a through hole in the resin substrate by irradiating the resin substrate with pulsed laser light. In the forming of the through hole, an interval of irradiation of the pulsed laser light at each point on the resin substrate is 5 msec or more.

1 . A laser processing apparatus that forms a through hole by irradiating a resin substrate with pulsed laser light, the laser processing apparatus comprising:
 a laser light source that emits pulsed laser light;   a stage on which to place a resin substrate including a resin layer and a metal layer that covers at least a part of one surface of the resin layer;   an optical system that guides the pulsed laser light emitted from the laser light source to the resin substrate placed on the stage;   a scanning section that moves at least one of the stage and a condensing point of the pulsed laser light guided by the optical system to relatively move the resin substrate placed on the stage and the condensing point of the pulsed laser light; and   a control section that controls an operation of the scanning section, wherein:   the control section controls the scanning section to perform a plurality of laps of scanning with the pulsed laser light along a predetermined circumference of the through hole, wherein an interval of irradiation of the pulsed laser light at each point on the predetermined circumference between each lap is 5 msec or more.   
     
     
         2 . The laser processing apparatus according to  claim 1 , wherein:
 a scanning time of one lap of the predetermined circumference with the pulsed laser light is less than 5 msec; and   irradiation of the pulsed laser light is intermittently stopped such that the interval of irradiation of the pulsed laser light at each point on the predetermined circumference between each lap is 5 msec or more.   
     
     
         3 . The laser processing apparatus according to  claim 1 , wherein the pulsed laser light includes a pulse width of 10 psec to 100 nsec. 
     
     
         4 . The laser processing apparatus according to  claim 1 , wherein the pulsed laser light includes a repetition frequency of 100 kHz or greater. 
     
     
         5 . The laser processing apparatus according to  claim 1 , wherein:
 the interval of irradiation including:   an interval of the pulsed laser light at a given point along the predetermined circumference of the through hole on the resin substrate, and   an interval between irradiation with the pulsed laser light of an nth-round and irradiation with the pulsed laser light of an (n+1)th-round.   
     
     
         6 . The laser processing apparatus according to  claim 1 , wherein:
 a scanning speed of the pulsed laser light to the resin substrate is 200 mm/sec or more; and   an output of the pulsed laser light is 10 W or greater.   
     
     
         7 . The laser processing apparatus according to  claim 1 , wherein:
 a wavelength of the pulsed laser light is 250 to 2000 nm; and   an output of the pulsed laser light is 10 W or greater.   
     
     
         8 . The laser processing apparatus according to  claim 1 , wherein:
 the condensing point of the pulsed laser light is located in the resin layer;   a wavelength of the pulsed laser light is 355 nm;   a pulse energy of the pulsed laser light is 3 μJ or greater;   a fluence of the pulsed laser light on the surface of the resin substrate is 3 J/cm 2  or greater; and   a fluence of the pulsed laser light at the condensing point is 10 J/cm 2  or greater.