Laser irradiation method

摘要

In processing an object by irradiating it with laser light, a laser irradiation chamber is evacuated to a pressure value suitable for the intended laser light processing and the laser light processing is performed with the pressure in the chamber kept constant at the above value. Further, electrodes are provided in the laser irradiation chamber, and the inside of the chamber is cleaned by introducing an etching gas into the chamber during or immediately before the laser light irradiation and rendering the etching gas active.