Apparatus for transforming semiconducting thin layer

An apparatus for transforming a semiconducting thin layer, comprising:

• a hermetically sealed container comprising a substrate mount section for mounting thereon a substrate with a semiconducting thin layer formed thereon, and a light transmissive window for introducing a laser beam;
• laser beam irradiation means which is provided outside the hermetically sealed container and applies a nonvibrating laser beam through the light transmissive window, for heat-melting the semiconducting thin layer;
• holding means for fixing and holding the substrate on the substrate mount section;
• and
• pressure control means which regulate the flow rate of gas fed into the hermetically sealed container to control the pressure of the atmosphere within the hermetically sealed container at the time of irradiation with the laser beam at a value above a vapor pressure specified by the temperature of the heat-melted semiconducting thin layer.