Method of manufacturing semiconductor device

1. A method of manufacturing a semiconductor device, comprising the steps of:

raising a temperature of a sapphire substrate which is included in the semiconductor device from a room temperature to a preheat temperature of 150 degree C. to 450 degree C. and keeping the preheat temperature for a first predetermined time, thereby preheating the semiconductor device; and

subsequently raising a temperature of the sapphire substrate from the preheat temperature to a thermal reaction temperature of 500 degree C. or higher and keeping the thermal reaction temperature for a second predetermined time, thereby performing a thermal reaction treatment of the semiconductor device;

wherein the step for the preheating is performed by irradiating a susceptor facing the semiconductor device with light emitted from a lamp and subsequently turning off the lamp.

2. The method according to claim 1 , wherein the first predetermined time is 10 seconds or longer.

3. The method according to claim 1 , wherein the preheat temperature ranges from 250° C. to 350° C.

4. The method according to claim 3 , wherein the first predetermined time is 20 seconds or longer.

5. The method according to claim 1 , wherein the step for the thermal reaction treatment includes the steps of:

raising the temperature of the sapphire substrate from the preheat temperature to a pre-anneal temperature of 450° C. to 550° C. and keeping the pre-anneal temperature for a third predetermined time; and

raising the temperature of the sapphire substrate from the pre-anneal temperature to the thermal reaction temperature of 600° C. to 900° C. and keeping the thermal reaction temperature for a fourth predetermined time.

6. The method according to claim 1 , wherein the step for the thermal reaction treatment includes the steps of:

raising the temperature of the sapphire substrate from the preheat temperature to a pre-anneal temperature 200° C. to 550° C. lower than the thermal reaction temperature and keeping the pre-anneal temperature for a third predetermined time; and

raising the temperature of the sapphire substrate from the pre-anneal temperature to the thermal reaction temperature of 900° C. or higher and keeping the thermal reaction temperature for a fourth predetermined time.

7. The method according to claim 1 , wherein the semiconductor device includes:

the sapphire substrate; and

a semiconductor layer disposed on a surface of the sapphire substrate.

8. The method according to claim 7 , wherein the semiconductor layer is a silicon layer.

9. The method according to claim 7 , wherein the semiconductor device further includes at least one of a conductive thin film and an insulating thin film disposed on the semiconductor layer.