US Patent 7622000 Laser processing apparatus and laser processing method

A notch or the like of a wafer is detected via a guide member by means of a CCD camera provided so that an optical axis is coaxial to an optical axis of a laser beam, and alignment of the wafer is carried out. Next, in a state in which liquid ejected from a main nozzle or sub-nozzles is guided by means of the guide member, a laser beam whose optical axis is provided to be coaxial to the optical axis of the CCD camera is irradiated via the guide member. In addition, a predetermined processing operation is carried out with respect to the surface while an irradiation position of the laser beam is moved in a horizontal direction. The wafer is then transported from a chuck to the outside, and then, a purge gas is supplied to a bottom face of the guide member, and the bottom face is dried.