TWI587959B

PROBLEM TO BE SOLVED: To provide a substrate processing method and a processing apparatus for concurrently processing an upside substrate and a downside substrate of a laminated substrate.SOLUTION: A substrate processing method for performing scribe groove processing by irradiating a laminated substrate W placed on a table 12 with a laser beam, includes the steps of: emitting a short pulse laser beam having a pulse width of 10seconds or less from a laser source 20; branching the laser beam into two beams and transmitting two laser beams Land Lat different divergence angles through a focus-forming convex lens 37 to form two focal points P' and S' with different focal positions; and making the focal point S' of one of the laser beams arrive in an upside substrate Wof the laminated substrate W, whereas making the focal point P' of the other laser beam arrive in a downside substrate Wof the laminated substrate W, thereby concurrently processing the upside substrate Wand the downside substrate Wby the focal points