Light-emission heat treatment apparatus
AssigneeSCREEN Holdings Co., Ltd.
InventorsRyuta TOBE, Naoto MORI, Takahiro KITAZAWA
Life of this patent
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Abstract
A flash lamp emits a flash of light to a front surface of a semiconductor wafer held in a chamber to heat the semiconductor wafer. A GCT thyristor is connected in parallel with the flash lamp. After a lapse of a predetermined time period since a current starts to flow through the flash lamp, the GCT thyristor enters an ON state. This allows a discharge current to flow through the GCT thyristor with a smaller impedance, and prevents any current from flowing through the flash lamp. Consequently, a tail current flowing through the flash lamp can be suppressed. Furthermore, reduction in a voltage charged into a capacitor can prevent the life of the flash lamp from being shortened.
Claims6
A heat treatment apparatus that heats a substrate by emitting a flash of light to the substrate, the apparatus comprising:
- a chamber housing the substrate;
- a holder holding the substrate in the chamber;
- a flash lamp emitting the flash of light to the substrate, the substrate being held by the holder;
- a discharge circuit allowing a current to flow through the flash lamp and causing the flash lamp to emit the flash of light;
- and
- a controller controlling the discharge circuit,
- wherein the discharge circuit includes a first switching element connected in parallel with the flash lamp, and
- the controller is configured to render the first switching element conductive to stop the emission of the flash lamp.
A heat treatment apparatus that heats a substrate by emitting a flash of light to the substrate, the apparatus comprising:
- a chamber housing the substrate;
- a holder holding the substrate in the chamber;
- a flash lamp emitting the flash of light to the substrate, the substrate being held by the holder;
- a discharge circuit allowing a current to flow through the flash lamp and causing the flash lamp to emit the flash of light;
- and
- a controller controlling the discharge circuit,
- wherein the discharge circuit includes a gate commutated turn-off thyristor connected in series with the flash lamp, and
- the controller is configured to set the gate commutated turn-off thyristor in a blocking state to stop the emission of the flash lamp.
Dependencies are inferred from the claim text.