Light irradiation heat treatment method and light irradiation heat treatment apparatus

1. A light irradiation heat treatment method for a workpiece supported in a furnace, in which a plane-shaped light irradiation heating component faces one surface of the workpiece, the method comprising:

setting an intensity distribution for light irradiated from the light irradiation heating component in accordance with the resistivity of the workpiece; and

irradiating light having the set light intensity distribution toward the workpiece to raise the temperature of the workpiece.

2. The method of claim 1 , wherein the intensity distribution for the light is set for a flatly uniform intensity distribution when the resistivity of the workpiece is less than 1 ohm-cm.

3. The method of claim 1 , wherein the intensity distribution for the light is set such that the light intensity of a peripheral portion of the distribution is less than that of a central portion when the resistivity of the workpiece is not less than 1 ohm-cm.

4. The method of claim 1 , further comprising:

raising the temperature of the workpiece by setting the light intensity of a peripheral portion of the distribution less than that of a central portion and irradiating the workpiece with the set intensity distribution;

irradiating, after raising the temperature of the workpiece using the non-uniform intensity distribution, the workpiece with light having a flatly uniform intensity distribution; and

heat-treating the workpiece.

5. The method of claim 4 , wherein the flatly uniform light intensity distribution provided by the light irradiation heating component has the geometric form of a concentric circle-shaped distribution and this distribution is irradiated onto a circle-shaped workpiece having a resistivity that is not less than 1 ohm-cm.

6. A light irradiation heat treatment apparatus comprising:

a support element for supporting a workpiece provided in a furnace;

a plane-shaped light irradiation heating component that faces one surface of the workpiece;

a temperature measuring component that faces the surface on the other side with respect to the one surface of the workpiece; and

a light irradiation intensity control component that controls a light irradiation intensity distribution, in a plane of the light irradiation heating component, based on the resistivity of the workpiece, when raising the temperature of the workpiece.

7. A light irradiation heat treatment apparatus comprising:

a support element for supporting a workpiece provided in a furnace;

a plane-shaped light irradiation heating component that faces one surface of the workpiece;

a temperature measuring component that faces the surface on the other side with respect to the one surface of the workpiece;

a resistivity measurement component that measures the resistivity of the workpiece; and

a light irradiation intensity control component that controls a light irradiation intensity distribution, in a plane of the light irradiation heating component, based on the measured resistivity of the workpiece, when raising the temperature of the workpiece.

8. The light irradiation heat treatment apparatus according to any one of claims 6 or 7 , wherein the light irradiation heating component consists of a group of heat lamps that are flatly arranged, such that the group of the heat lamps is split into a plurality of flat areas and the light irradiation intensity for each area may be set independently of the other areas.

9. The light irradiation heat treatment apparatus according to any one of claims 6 or 7 , wherein the light irradiation intensity control component controls the intensity distribution for the light such that:

a flatly uniform intensity distribution is applied to raise the temperature of the workpiece when the resistivity of the workpiece is less than 1 ohm-cm, and

a varying intensity distribution is applied to raise the temperature of the workpiece when the resistivity is not less than 1 ohm-cm.

10. The light irradiation heat treatment apparatus of claim 8 , wherein the group of heat lamps is split into a plurality of areas that each have the shape of a flatly concentric circle and the light provided by the heat lamps is irradiated onto a semiconductor substrate workpiece.

11. The light irradiation heat treatment apparatus of claim 9 , wherein the group of heat lamps is split into a plurality of areas that each have the shape of a flatly concentric circle and the light provided by the heat lamps is irradiated onto a semiconductor substrate workpiece.

12. The method of claim 1 , further comprising raising the temperature of the workpiece by setting the light intensity of a peripheral portion of the distribution less than that of a central portion and irradiating the workpiece with the set intensity distribution; irradiating, after raising the temperature of the workpiece using the non-uniform intensity distribution, the workpiece with light having a flatly uniform intensity distribution; and heat-treating the workpiece, wherein the flatly uniform light intensity distribution provided by the light irradiation heating component has the geometric form of a concentric circle-shaped distribution and this distribution is irradiated onto a circleshaped workpiece having a resistivity that is not less than 1 ohm-cm.

13. The method of claim 3 , further comprising raising the temperature of the workpiece by setting the light intensity of a peripheral portion of the distribution less than that of a central portion and irradiating the workpiece with the set intensity distribution; irradiating, after raising the temperature of the workpiece using the non-uniform intensity distribution, the workpiece with light having a flatly uniform intensity distribution; and heat-treating the workpiece, wherein the flatly uniform light intensity distribution provided by the light irradiation heating component has the geometric form of a concentric circle-shaped distribution and this distribution is irradiated onto a circle-shaped workpiece having a resistivity that is not less than 1 ohm-cm.