PURPOSE: To improve the evenness of irradiated light as well as the energy efficiency by a method wherein non light emitting parts of multiple annular light source concentri cally arranged centered around the normal to the surface of an element to be irradiated are combined with one another so as not to be positioned within the same radius passing the concentric center.
CONSTITUTION: A wafer 5 to be processed is arranged in a chamber 2 transmitting irradiated light for heating. For example, four each of annular heating light sources 1aW1d are provide on the surface in parallel with the upper and lower surfaces of chamber 2 as if holding the chamber 2. Said light sources 1aW1d are arranged at almost equivalent intervals concentrically centered around a straight line corresponding to the normal at the central position of the wafer 5. As for the circular light sources, e.g., halogen lamps with resistance wire or flash discharge lamps are applicable. In such a constitution, multiple circular light sources concentrically arranged are combined with one another so that non light emitting parts may not be positioned in the same radius direction passing the concentric with the exception of the non light emitting part of only one annular light source. Through these procedures, the distribution of evenness with the illumination intensity on the surface of an element to be irradiated can be improved.
ICHIKAWA HAJIME
YOMOTO MASAHIKO
KATO SHIGERU
