Screen Holdings Co., Ltd.

Hikaru Kawarazaki

Hideaki Tanimura

Masashi Furukawa

Kazuhiko Fuse

Shinichi Kato

Takayuki Aoyama

Makoto Abe

Akitsugu Ueda

Takahiro Yamada

Yoshihide Nozaki

Shinji Miyawaki

Yasuaki Kondo

A semiconductor wafer held by a holding part in a chamber is irradiated and heated with halogen light emitted from a plurality of halogen lamps. A cylindrical louver and an annular light-shielding member, both made of opaque quartz, are provided between the halogen lamps and the semiconductor wafer. The outer diameter of the light-shielding member is smaller than the inner diameter of the louver. Light emitted from the halogen lamps and passing through a clearance between the inner wall surface of the louver and the outer circumference of the light-shielding member is applied to a peripheral portion of the semiconductor wafer where a temperature drop is likely to occur. On the other hand, light travelling toward an overheat region that has a higher temperature than the other region and appears in the surface of the semiconductor wafer when only a louver is installed is blocked off by the light-shielding member.

Light-irradiation heat treatment apparatus

A semiconductor wafer to be treated is heated at a first preheating temperature ranging from 100 to 200&#xb0; C. while a pressure in a chamber housing the semiconductor wafer is reduced to a pressure lower than an atmospheric pressure. After the semiconductor wafer is preheated to increase the temperature into a second preheating temperature ranging from 500 to 700&#xb0; C. while the pressure in the chamber is restored to a pressure higher than the reduced pressure, a flash lamp emits a flashlight to a surface of the semiconductor wafer. Heating the semiconductor wafer at the first preheating temperature that is a relatively low temperature enables, for example, the moisture absorbed on the surface of the semiconductor wafer in trace amounts to be desorbed from the surface, and also enables the flash heating treatment to be performed with oxygen derived from such absorption removed as much as possible.

Heat treatment method including low temperature degassing before flash lamp anneal and heat treatment apparatus thereof

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

Over a front surface of a silicon semiconductor wafer is deposited a high dielectric constant film with a silicon oxide film, serving as an interface layer, provided between the semiconductor wafer and the high dielectric constant film. After a chamber houses the semiconductor wafer, a chamber's pressure is reduced to be lower than atmospheric pressure. Subsequently, a gaseous mixture of ammonia and nitrogen gas is supplied into the chamber to return the pressure to ordinary pressure, and the front surface is irradiated with a flash light, thereby performing post deposition annealing (PDA) on the high dielectric constant film. Since the pressure is reduced once to be lower than atmospheric pressure and then returned to ordinary pressure, a chamber's oxygen concentration is lowered remarkably during the PDA. This restricts an increase in thickness of the silicon oxide film underlying the high dielectric constant film by oxygen taken in during the PDA.

Light-irradiation heat treatment method and heat treatment apparatus

A front surface of a semiconductor wafer is momentarily heated by irradiation with a flash of light from flash lamps. An upper radiation thermometer and a high-speed radiation thermometer unit measure a temperature of the front surface of the semiconductor wafer after the irradiation with the flash of light. The temperature data are sequentially accumulated, so that a temperature profile is acquired. An analyzer determines the highest measurement temperature of the semiconductor wafer subjected to the flash irradiation from the temperature profile to calculate a jump distance of the semiconductor wafer from a susceptor, based on the highest measurement temperature. If the calculated jump distance is greater than a predetermined threshold value, there is a high probability that the semiconductor wafer is significantly out of position, so that the transport of the semiconductor wafer to the outside is stopped.

Light irradiation type heat treatment method and heat treatment apparatus

Hydrogen annealing for heating a semiconductor wafer on which a thin film containing a dopant is deposited to an annealing temperature under an atmosphere containing hydrogen is performed. A native oxide film is inevitably formed between the thin film containing the dopant and the semiconductor wafer, however, by performing hydrogen annealing, the dopant atoms diffuse relatively easily in the native oxide film and accumulate at the interface between the front surface of the semiconductor wafer and the native oxide film. Subsequently, the semiconductor wafer is preheated to a preheating temperature under a nitrogen atmosphere, and then, flash heating treatment in which the front surface of the semiconductor wafer is heated to a peak temperature for less than one second is performed. The dopant atoms are diffused and activated in a shallow manner from the front surface of the semiconductor wafer, thus, the low-resistance and extremely shallow junction is obtained.

Heat treatment method for dopant introduction

A heat treatment apparatus is provided with two cool chambers, that is, a first cool chamber and a second cool chamber. A semiconductor wafer before treatment is alternately carried into the first cool chamber or the second cool chamber and then transported to a heat treatment part by a transport robot after a nitrogen purge is performed. The semiconductor wafer after being heat-treated in the heat treatment part is alternately transported to the first cool chamber or the second cool chamber to be cooled. A sufficient cooling time is secured for the independent semiconductor wafer, and a reduction in throughput as the whole heat treatment apparatus can be suppressed.

A substrate in a chamber is preheated through light irradiation by a halogen lamp and then heated through irradiation with flash light from a flash lamp. Ammonia is supplied to the chamber from an ammonia supply mechanism to form ammonia atmosphere. The temperature of the substrate at heating processing is measured by a radiation thermometer. When the measurement wavelength band of the radiation thermometer overlaps with the absorption wavelength band of ammonia, the set emissivity of the radiation thermometer is changed and set to be lower than the actual emissivity of the substrate. When radiation light emitted from the substrate is absorbed by the ammonia atmosphere, the radiation thermometer can accurately output the temperature of the substrate as a measured value by reducing the set emissivity of the radiation thermometer.

Thermal processing apparatus and thermal processing method through light irradiation

When an insulated gate bipolar transistor is incorporated in a drive circuit of a flash lamp, so that a light emission pattern of the flash lamp is freely defined, a temperature change pattern of a surface of a semiconductor wafer that receives the emission of flash light can be adjusted. The length of diffusion of impurities can be controlled by rising a surface temperature of the semiconductor wafer from a preheating temperature to a diffusion temperature through emission of flash light and maintaining the surface temperature at the diffusion temperature for a time period not shorter than 1 millisecond and not longer than 10 milliseconds. Subsequently, the impurities can be activated by rising the surface temperature of the semiconductor wafer from the diffusion temperature to an activation temperature.

Thermal processing method through light irradiation

A metal film is deposited on a front surface of a semiconductor wafer of silicon. After the semiconductor wafer is received in a chamber, the pressure in the chamber is reduced to a pressure lower than atmospheric pressure. Thereafter, nitrogen gas is supplied into the chamber to return the pressure in the chamber to ordinary pressure, and the front surface of the semiconductor wafer is irradiated with a flash of light, so that a silicide that is a compound of the metal film and silicon is formed. The oxygen concentration in the chamber is significantly lowered during the formation of the silicide because the pressure in the chamber is reduced once to the pressure lower than atmospheric pressure and then returned to the ordinary pressure. This suppresses the increase in resistance of the silicide resulting from the entry of oxygen in the atmosphere in the chamber into defects near the interface between the metal film and a base material.

A semiconductor wafer held by a holder within a chamber is irradiated and heated with halogen light emitted from multiple halogen lamps. Cylindrical outer and inner louvers made of opaque quartz are provided between the halogen lamps and the semiconductor wafer. A reflector is provided in an area of tube walls of the halogen lamps that faces the spacing between the inner wall surface of the outer louver and the outer wall surface of the inner louver. The spacing between the two louvers is located immediately below and faces the peripheral portion of the semiconductor wafer. Thus, the illuminance of light that reaches the peripheral portion of the semiconductor wafer where a temperature drop is likely to occur will be higher than the illuminance of light that travels toward the central portion from the halogen lamps. This configuration will help make uniform the in-plane temperature distribution of the semiconductor wafer.

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Kyoto, Japan

Hikaru Kawarazaki