Abstract: Four wafer pins are fixed in a chamber and spaced at intervals of 90 degrees. Four support pins are provided in a wafer pocket of a susceptor and spaced at intervals of 90 degrees. The four wafer pins and the four support pins are disposed concyclically in an alternating manner at intervals of 45 degrees. When halogen lamps irradiate a semiconductor wafer with light to heat the semiconductor wafer, the susceptor is moved upwardly and downwardly, so that the semiconductor wafer is shifted between the wafer pins and the support pins. This eliminates the occurrence of a problem such that the quartz pins which are relatively low in temperature are continuously kept in contact with particular places of the semiconductor wafer to improve the uniformity of the in-plane temperature distribution of the semiconductor wafer.

Abstract: First flash irradiation from flash lamps is performed on an upper surface of a semiconductor wafer supported on a temperature equalizing ring of a holder to cause the semiconductor wafer to jump up from the temperature equalizing ring into midair. While the semiconductor wafer is in midair above the temperature equalizing ring, second flash irradiation from the flash lamps is performed on the upper surface of the semiconductor wafer to increase the temperature of the upper surface of the semiconductor wafer to a treatment temperature. Cracking in the semiconductor wafer is prevented because the second flash irradiation is performed while the semiconductor wafer is in midair and subject to no restraints.

Abstract: A susceptor that holds a semiconductor wafer placed thereon is capable of moving up and down inside a chamber. For preheating with a halogen lamp, the susceptor moves to a preheating position. The preheating position is a height of the susceptor that achieves the most uniform in-plane illumination distribution of light emitted from the halogen lamp and applied to the semiconductor wafer. After the preheating is finished, the susceptor moves to a flash heating position for irradiation with a flash from a flash lamp. The flash heating position is a height of the susceptor that achieves the most uniform in-plane illumination distribution of a flash emitted from the flash lamp and applied to the semiconductor wafer.

Abstract: Flash lamps connected to short-pulse circuits and flash lamps connected to long-pulse circuits are alternately arranged in a line. The duration of light emission from the flash lamps connected to the long-pulse circuits is longer than the duration of light emission from the flash lamps connected to the short-pulse circuits. A superimposing of a flash of light with a high peak intensity from the flash lamps that emit light for a short time and a flash of light with a gentle peak from the flash lamps that emit light for a long time can increase the temperature of even a deep portion of a substrate to an activation temperature or more without heating a shallow portion near the substrate surface more than necessary. This achieves the activation of deep junctions without causing substrate warpage or cracking.

Abstract: Flash lamps connected to short-pulse circuits and flash lamps connected to long-pulse circuits are alternately arranged in a line. The duration of light emission from the flash lamps connected to the long-pulse circuits is longer than the duration of light emission from the flash lamps connected to the short-pulse circuits. A superimposing of a flash of light with a high peak intensity from the flash lamps that emit light for a short time and a flash of light with a gentle peak from the flash lamps that emit light for a long time can increase the temperature of even a deep portion of a substrate to an activation temperature or more without heating a shallow portion near the substrate surface more than necessary. This achieves the activation of deep junctions without causing substrate warpage or cracking.

Abstract: Flash lamps connected to short-pulse circuits and flash lamps connected to long-pulse circuits are alternately arranged in a line. The duration of light emission from the flash lamps connected to the long-pulse circuits is longer than the duration of light emission from the flash lamps connected to the short-pulse circuits. A superimposing of a flash of light with a high peak intensity from the flash lamps that emit light for a short time and a flash of light with a gentle peak from the flash lamps that emit light for a long time can increase the temperature of even a deep portion of a substrate to an activation temperature or more without heating a shallow portion near the substrate surface more than necessary. This achieves the activation of deep junctions without causing substrate warpage or cracking.

Abstract: After the completion of the transport of a semiconductor wafer into a chamber, the flow rate of nitrogen gas supplied into the chamber is decreased. In this state, a preheating treatment and flash irradiation are performed. The flow rate of nitrogen gas supplied into the chamber is increased when the temperature of the front surface of the semiconductor wafer is decreased to become equal to the temperature of the back surface thereof after reaching its maximum temperature by the irradiation of the substrate with a flash of light. Thereafter, the supply flow rate of nitrogen gas is maintained at a constant value until the semiconductor wafer is transported out of the chamber. This achieves the reduction in particles deposited on the semiconductor wafer while suppressing adverse effects resulting from the nonuniform in-plane temperature distribution of the semiconductor wafer.

Abstract: Three support members made of silicon carbide are provided fixedly on an inner periphery of the support ring. The support members are inclined at an angle in the range of 15 to 30 degrees with respect to a horizontal plane. With an outer peripheral edge of a semiconductor wafer supported by the three support members, a heating treatment is performed by irradiating the semiconductor wafer with halogen light from halogen lamps. Silicon carbide absorbs the halogen light better than quartz. The support members support the outer peripheral edge of the semiconductor wafer in point contacting relationship, so that the contact between a holder and the semiconductor wafer is minimized. This minimizes the disorder of the temperature distribution of the semiconductor wafer due to the support members to achieve the uniform heating of the semiconductor wafer.

Abstract: Flash lamps connected to short-pulse circuits and flash lamps connected to long-pulse circuits are alternately arranged in a line. The duration of light emission from the flash lamps connected to the long-pulse circuits is longer than the duration of light emission from the flash lamps connected to the short-pulse circuits. A superimposing of a flash of light with a high peak intensity from the flash lamps that emit light for a short time and a flash of light with a gentle peak from the flash lamps that emit light for a long time can increase the temperature of even a deep portion of a substrate to an activation temperature or more without heating a shallow portion near the substrate surface more than necessary. This achieves the activation of deep junctions without causing substrate warpage or cracking.

Abstract: In light-irradiation heating with a total irradiation time of one second or less, two-stage irradiation is performed, including a first stage of light irradiation of a semiconductor wafer, which irradiation produces an output waveform that reaches a peak at a given emission output; and a second stage of supplemental light irradiation of the semiconductor wafer, which irradiation is started after the peak, producing an emission output smaller than the above given emission output. The emission output in the second stage is two thirds or less than the above given emission output at the peak. The first-stage light-irradiation time is between 0.1 and 10 milliseconds, and the second-stage light-irradiation time is 5 milliseconds or more.

Abstract: First flash irradiation from flash lamps is performed on an upper surface of a semiconductor wafer supported on a temperature equalizing ring of a holder to cause the semiconductor wafer to jump up from the temperature equalizing ring into midair. While the semiconductor wafer is in midair above the temperature equalizing ring, second flash irradiation from the flash lamps is performed on the upper surface of the semiconductor wafer to increase the temperature of the upper surface of the semiconductor wafer to a treatment temperature. Cracking in the semiconductor wafer is prevented because the second flash irradiation is performed while the semiconductor wafer is in midair and subject to no restraints.

Abstract: A susceptor for holding a semiconductor wafer to be flash-heated by a flash of light emitted from flash lamps is formed of transparent quartz. The susceptor has a backside surface only which is roughened by shot blasting to provide a ground-glass-like surface. When a flash of light is emitted, part of the flash of light emitted from the flash lamps and passing by a peripheral portion of the semiconductor wafer held by the susceptor into the susceptor reaches the ground-glass-like backside surface and is diffusely reflected therefrom. Part of the diffusely reflected light impinges on the peripheral portion of the semiconductor wafer held by the susceptor to thereby heat the low temperature regions which have appeared in the peripheral portion of the semiconductor wafer.

Abstract: First irradiation which causes an emission output from a flash lamp to reach its maximum value over a time period in the range of 1 to 20 milliseconds is performed to increase the temperature of a front surface of a semiconductor wafer from a preheating temperature to a target temperature for a time period in the range of 1 to 20 milliseconds. This achieves the activation of the impurities. Subsequently, second irradiation which gradually decreases the emission output from the maximum value over a time period in the range of 3 to 50 milliseconds is performed to maintain the temperature of the front surface within a ±25° C. range around the target temperature for a time period in the range of 3 to 50 milliseconds. This prevents the occurrence of process-induced damage while suppressing the diffusion of the impurities.

Abstract: The first flash irradiation is performed on a semiconductor wafer preheated to 500° C. to heat a front surface of the semiconductor wafer. Thereafter, the second flash irradiation is performed to reheat the front surface of the semiconductor wafer before the temperature of the front surface of the semiconductor wafer becomes equal to the temperature of a back surface of the semiconductor wafer. Thus, the second flash irradiation is performed before the temperature of the front surface of the semiconductor wafer falls. Even if less energy is consumable by the second flash irradiation, the efficiency of heating of the front surface of the semiconductor wafer resulting from each iteration of the flash irradiation is improved.

Abstract: In light-irradiation heating with a total irradiation time of one second or less, two-stage irradiation is performed, including a first stage of light irradiation of a semiconductor wafer, which irradiation produces an output waveform that reaches a peak at a given emission output; and a second stage of supplemental light irradiation of the semiconductor wafer, which irradiation is started after the peak, producing an emission output smaller than the above given emission output. The emission output in the second stage is two thirds or less than the above given emission output at the peak. The first-stage light-irradiation time is between 0.1 and 10 milliseconds, and the second-stage light-irradiation time is 5 milliseconds or more.

Abstract: Flash lamps connected to short-pulse circuits and flash lamps connected to long-pulse circuits are alternately arranged in a line. The duration of light emission from the flash lamps connected to the long-pulse circuits is longer than the duration of light emission from the flash lamps connected to the short-pulse circuits. A superimposing of a flash of light with a high peak intensity from the flash lamps that emit light for a short time and a flash of light with a gentle peak from the flash lamps that emit light for a long time can increase the temperature of even a deep portion of a substrate to an activation temperature or more without heating a shallow portion near the substrate surface more than necessary. This achieves the activation of deep junctions without causing substrate warpage or cracking.

Abstract: In light-irradiation heating with a total irradiation time of one second or less, two-stage irradiation is performed, including a first stage of light irradiation of a semiconductor wafer, which irradiation produces an output waveform that reaches a peak at a given emission output; and a second stage of supplemental light irradiation of the semiconductor wafer, which irradiation is started after the peak, producing an emission output smaller than the above given emission output. The emission output in the second stage is two thirds or less than the above given emission output at the peak. The first-stage light-irradiation time is between 0.1 and 10 milliseconds, and the second-stage light-irradiation time is 5 milliseconds or more. This allows the temperature of the semiconductor wafer even at a somewhat greater depth below the surface to be raised to some extent while allowing the surface temperature to be maintained at a generally constant processing temperature.

Abstract: Flash lamps connected to short-pulse circuits and flash lamps connected to long-pulse circuits are alternately arranged in a line. The duration of light emission from the flash lamps connected to the long-pulse circuits is longer than the duration of light emission from the flash lamps connected to the short-pulse circuits. A superimposing of a flash of light with a high peak intensity from the flash lamps that emit light for a short time and a flash of light with a gentle peak from the flash lamps that emit light for a long time can increase the temperature of even a deep portion of a substrate to an activation temperature or more without heating a shallow portion near the substrate surface more than necessary. This achieves the activation of deep junctions without causing substrate warpage or cracking.

Abstract: Flash lamps connected to short-pulse circuits and flash lamps connected to long-pulse circuits are alternately arranged in a line. The duration of light emission from the flash lamps connected to the long-pulse circuits is longer than the duration of light emission from the flash lamps connected to the short-pulse circuits. A superimposing of a flash of light with a high peak intensity from the flash lamps that emit light for a short time and a flash of light with a gentle peak from the flash lamps that emit light for a long time can increase the temperature of even a deep portion of a substrate to an activation temperature or more without heating a shallow portion near the substrate surface more than necessary. This achieves the activation of deep junctions without causing substrate warpage or cracking.

Abstract: Flash lamps connected to short-pulse circuits and flash lamps connected to long-pulse circuits are alternately arranged in a line. The duration of light emission from the flash lamps connected to the long-pulse circuits is longer than the duration of light emission from the flash lamps connected to the short-pulse circuits. A superimposing of a flash of light with a high peak intensity from the flash lamps that emit light for a short time and a flash of light with a gentle peak from the flash lamps that emit light for a long time can increase the temperature of even a deep portion of a substrate to an activation temperature or more without heating a shallow portion near the substrate surface more than necessary. This achieves the activation of deep junctions without causing substrate warpage or cracking.