Screen Holdings Co., Ltd.

Dainippon Screen Mfg. Co., Ltd.

Yoshihide Nozaki

Tomohiro Ueno

Hikaru Kawarazaki

Mao Omori

Yoshio Ito

Takahiro Kitazawa

Film information about a thin film formed on the front surface of a semiconductor wafer, substrate information about the semiconductor wafer, and an installation angle of an upper radiation thermometer are set and input. Emissivity of the front surface of the semiconductor wafer formed with a multilayer film is calculated based on the various kinds of information. Further, a weighted average efficiency of the emissivity of the front surface of the semiconductor wafer is determined based on a sensitivity distribution of the upper radiation thermometer. Front surface temperature of the semiconductor wafer at the time of heat treatment is measured using the determined weighted average efficiency of the emissivity. The emissivity is determined based on the film information and the like, so that the front surface temperature of the semiconductor wafer can be accurately measured even when thin films are formed in multiple layers.

Heat treatment method and heat treatment apparatus of light irradiation type

A semiconductor wafer is preheated with a halogen lamp, and then is heated by irradiation with a flash of light emitted from a flash lamp. The preheating with the halogen lamp is continued for a short time even after the flash lamp turns off. A radiation thermometer measures a front surface temperature and a back surface temperature of the semiconductor wafer. A temperature integrated value is calculated by integration of temperatures of the semiconductor wafer measured during a period from a start of the flash irradiation to an end of the heating of the semiconductor wafer. It is determined that the semiconductor wafer is cracked at the time of flash irradiation when the calculated temperature integrated value deviates from a preset range between an upper limit value and a lower limit value.

Light irradiation type heat treatment method and heat treatment apparatus

A semiconductor wafer is heated by a flash of light emitted from a flash lamp after being preheated by a halogen lamp. Temperature of the semiconductor wafer immediately before the flash of light is emitted is measured by a lower radiation thermometer. At the time of irradiation with a flash of light, an upper radiation thermometer measures temperature increase of a front surface of the semiconductor wafer. Front surface temperature of the semiconductor wafer is calculated by adding the temperature increase of the front surface of the semiconductor wafer at the time of irradiation with a flash of light measured by the upper radiation thermometer to the back surface temperature of the semiconductor wafer measured by the lower radiation thermometer.

Heat treatment method of light irradiation type

Multiple theoretical reflectances determined by simulation for a silicon substrate with thin films of multiple types and thicknesses formed thereon are registered in association with the types and the thicknesses in a database. A carrier storing semiconductor wafers in a lot is transported into a heat treatment apparatus. A reflectance of a semiconductor wafer is measured by applying light to a surface of the semiconductor wafer. The theoretical reflectance of the semiconductor wafer is calculated from the measured reflectance thereof. A theoretical reflectance closely resembling the theoretical reflectance of the semiconductor wafer is extracted from among the multiple theoretical reflectances registered in the database, whereby the type and thickness of the thin film formed on the surface of the semiconductor wafer are specified. Treatment conditions for the semiconductor wafer are determined based on the specified type and thickness of the thin film.

After the maintenance of a heat treatment apparatus, a susceptor and a heating plate are moved upwardly and a nitrogen gas flow from an inlet toward an outlet passage is produced prior to heat treating a semiconductor wafer. In this state, flash lamps are turned on to cause momentary expansion and contraction of the gas in a chamber, thereby scattering particles deposited on a bottom plate, etc. The scattered particles are removed by the nitrogen gas passing through a bottom portion of the chamber and discharged through the outlet passage. The particles are easily removed due to the flash lamps being turned on a predetermined number of times at fixed time intervals while folowing the nitrogen gas. The heat treatment apparatus has a light-emission characteristic and easily removes the particles in the chamber.

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Kyoto, Japan

Yoshihide Nozaki