Light irradiation type heat treatment apparatus and heat treatment method

A heat treatment apparatus for heating a substrate by irradiating the substrate with light, comprising:

• a chamber for receiving a substrate therein;
• a plurality of first support pins for supporting the substrate in said chamber;
• a susceptor having a plurality of second support pins and for holding the substrate in said chamber;
• a continuously lighted lamp for irradiating the substrate received in said chamber with light to heat the substrate;
• a lifting drive for moving said susceptor upwardly and downwardly relative to said first support pins;
• and
• a controller configured to control said lifting drive so that a first state and a second state are alternately repeated when the substrate is heated by the irradiation with light from said continuously lighted lamp, said first state being such that said susceptor is in a relatively lowered position so that said first support pins protrude above said second support pins to support said substrate, said second state being such that said susceptor is in a relatively raised position so that said second support pins lie above said first support pins to support said substrate.