Prior to heat treatment of a semiconductor wafer to be treated, a dummy wafer is placed on a susceptor made of quartz, and the susceptor is preheated by irradiation with light from halogen lamps. A controller controls an output from the halogen lamps, based on the temperature of the susceptor measured with a radiation thermometer. The radiation thermometer receives infrared radiation of a wavelength longer than 4 μm to measure the temperature of the susceptor. The radiation thermometer is able to receive only infrared radiation emitted from the susceptor to accurately measure the temperature of the susceptor, regardless of whether or not a wafer is held by the susceptor, because quartz is opaque in a wavelength range longer than 4 μm.

To provide a light irradiation device using a plurality of flash lamps in which a structure that can emit high intensity light as a whole and enables a flash lamp to be used for a practical lifetime without increasing an input current to each lamp is adopted.

A light emission surface is provided on a distal end on a second electrode introducing part side of a light-emitting tube of a flash lamp including a first electrode introducing part and the second electrode introducing part, and a plurality of flash lamps are arranged in a standing manner on a top plate of a processing chamber so that the light emission surface faces the inside of the processing chamber.

When pressure in a chamber is once reduced lower than that when a flash of light is emitted and is maintained, after a flash lamp irradiates a semiconductor wafer accommodated in the chamber with the flash of light, a portion in the chamber, where gas is liable to remain, is eliminated. Then, when a flow rate of nitrogen gas to be supplied into the chamber is increased to discharge gas in the chamber, particles flying in the chamber due to flash irradiation can be smoothly discharged. As a result, the particles flying in the chamber can be prevented from being attached to an additional semiconductor wafer.

When pressure in a chamber is once reduced lower than that when a flash of light is emitted and is maintained, after a flash lamp irradiates a semiconductor wafer accommodated in the chamber with the flash of light, a portion in the chamber, where gas is liable to remain, is eliminated. Then, when a flow rate of nitrogen gas to be supplied into the chamber is increased to discharge gas in the chamber, particles flying in the chamber due to flash irradiation can be smoothly discharged. As a result, the particles flying in the chamber can be prevented from being attached to an additional semiconductor wafer.

Prior to heat treatment of a semiconductor wafer to be treated, a dummy wafer is placed on a susceptor made of quartz, and the susceptor is preheated by irradiation with light from halogen lamps. A controller controls an output from the halogen lamps, based on the temperature of the susceptor measured with a radiation thermometer. The radiation thermometer receives infrared radiation of a wavelength longer than 4 m to measure the temperature of the susceptor. The radiation thermometer is able to receive only infrared radiation emitted from the susceptor to accurately measure the temperature of the susceptor, regardless of whether or not a wafer is held by the susceptor, because quartz is opaque in a wavelength range longer than 4 m.

Prior to heat treatment of a semiconductor wafer to be treated, a dummy wafer is placed on a susceptor made of quartz, and the susceptor is preheated by irradiation with light from halogen lamps. A controller controls an output from the halogen lamps, based on the temperature of the susceptor measured with a radiation thermometer. The radiation thermometer receives infrared radiation of a wavelength longer than 4 m to measure the temperature of the susceptor. The radiation thermometer is able to receive only infrared radiation emitted from the susceptor to accurately measure the temperature of the susceptor, regardless of whether or not a wafer is held by the susceptor, because quartz is opaque in a wavelength range longer than 4 m.

A flash light source device includes: a flash lamp; a wiring board that is provided with a circuit configured to cause the flash lamp to emit light; a housing that is formed of a conductive material and accommodates the flash lamp and the wiring board; and an electromagnetic shield cable that includes a wire directly connected to the wiring board, an electromagnetic shield layer that covers the wire, and an insulating protective layer that covers the electromagnetic shield layer, and extends to the inside and outside of the housing through an opening formed in the housing. The electromagnetic shield layer is exposed at least at a part corresponding to the opening. The part corresponding to the opening in the electromagnetic shield layer is electrically connected to a part defining the opening in the housing.

A flash light source device includes: a flash lamp; a wiring board that is provided with a circuit configured to cause the flash lamp to emit light; a housing that is formed of a conductive material and accommodates the flash lamp and the wiring board; and an electromagnetic shield cable that includes a wire directly connected to the wiring board, an electromagnetic shield layer that covers the wire, and an insulating protective layer that covers the electromagnetic shield layer, and extends to the inside and outside of the housing through an opening formed in the housing. The electromagnetic shield layer is exposed at least at a part corresponding to the opening. The part corresponding to the opening in the electromagnetic shield layer is electrically connected to a part defining the opening in the housing.

Flash tubes for photographic use, in particular, a flash tube is adapted to provide a light output adapted to FP-sync, Flat Peak. The flash tube includes a length of glass tubing enclosing a gas for use in the flash tube, a cathode inside a first end part of glass tubing and an anode inside a second end part of glass tubing. The cathode includes an element that helps to ionize the gas that is wound around the cathode, such that a spark stream starts from the upper part of the cathode and is prevented from spreading down wards on the cathode and changing the arc length during the light output adapted to FP-sync.

Flash tubes for photographic use, in particular, a flash tube is adapted to provide a light output adapted to FP-sync, Flat Peak. The flash tube includes a length of glass tubing enclosing a gas for use in the flash tube, a cathode inside a first end part of glass tubing and an anode inside a second end part of glass tubing. The cathode includes an element that helps to ionize the gas that is wound around the cathode, such that a spark stream starts from the upper part of the cathode and is prevented from spreading down wards on the cathode and changing the arc length during the light output adapted to FP-sync.