Patent ID: 7935913

Claim:
An apparatus for heating a substrate by irradiating said substrate with light, comprising: a chamber body forming a space in which a substrate is processed, said chamber body comprising an opening; a light emitting part for emitting light through a transparent plate to a substrate inside said chamber body, said transparent plate closing said opening, said light emitting part comprising a flash lamp; a light entrance portion provided inside said chamber body, wherein light emitted from said light emitting part enters said light entrance portion through said transparent plate; a measuring part for measuring energy of light entering said light entrance portion, a calculation part for calculating a surface temperature of a substrate irradiated with light from said light emitting part on the basis of an output of said measuring part, and a heater for preliminarily heating a substrate inside said chamber body; wherein a substrate is heated by irradiating said substrate with flash light emitted from said flash lamp, and energy of said flash light during the entire heating is measured by said measuring part; and said calculation part calculates a second energy density of light emitted to a center of a substrate from a first energy density of light entering said light entrance portion and calculates a surface temperature of said substrate on the basis of said second energy density and a heating temperature by said heater.