Screen Holdings Co., Ltd.

Takayuki Aoyama

Shinichi Kato

Hideaki Tanimura

Kazuhiko Fuse

Hikaru Kawarazaki

Masashi Furukawa

Akitsugu Ueda

Mao Omori

Takahiro Yamada

Takahiro Kitazawa

Tomohiro Ueno

Shinji Miyawaki

Katsuichi Akiyoshi

Yasuaki Kondo

Kazunori Amago

When pressure in a chamber is brought to atmospheric pressure and the chamber is filled with an inert gas atmosphere, the atmosphere in the chamber is sucked into an oxygen concentration analyzer through a sampling line such that oxygen concentration in the chamber is measured by the oxygen concentration analyzer. When the pressure in the chamber is reduced to less than atmospheric pressure, nitrogen gas is supplied to the oxygen concentration analyzer through an inert gas supply line simultaneously with suspending the measurement of oxygen concentration in the chamber. Even when the measurement of oxygen concentration in the chamber is suspended, reverse flow to the oxygen concentration analyzer from a gas exhaust pipe can be prevented, and the oxygen concentration analyzer can be prevented from being exposed to exhaust from the chamber. The configuration results in maintaining measurement accuracy of the oxygen concentration analyzer in a low oxygen concentration range.

Light irradiation type heat treatment apparatus including oxygen analyzer and heat treatment method thereof

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 carrier containing a plurality of semiconductor wafers in a lot is transported into a heat treatment apparatus. Thereafter, a recipe specifying treatment procedures and treatment conditions is set for each of the semiconductor wafers. Next, a reflectance of each of the semiconductor wafers stored in the carrier is measured. Based on the set recipe and the measured reflectance of each semiconductor wafer, a predicted attainable temperature of each semiconductor wafer at the time of flash heating treatment is calculated, and the calculated predicted attainable temperature is displayed. This allows the setting of the treatment conditions with reference to the displayed predicted attainable temperature, to thereby easily achieve the setting of the heat treatment conditions.

Light irradiation type heat treatment method and heat treatment apparatus that calculates a temperature of a substrate based on a treatment recipe applicable thereto

From a stage of preheating by a halogen lamp to irradiation with a flash by a flash lamp, a radiation thermometer is used for measuring the temperature of a back surface of a semiconductor wafer. A increased temperature &#x394;T is determined by which the back surface of the semiconductor wafer is increased in temperature from the preheating temperature by irradiation with a flash. The specific heat of the semiconductor wafer has a known value. Further, the increased temperature &#x394;T is proportionate to the magnitude of energy applied to a front surface of the semiconductor wafer by irradiation with a flash. Thus, a front surface attained temperature of the semiconductor wafer can be determined using the increased temperature &#x394;T of the back surface of the semiconductor wafer during irradiation with a flash.

Light-irradiation type thermal processing method and thermal processing apparatus

A gallium nitride (GaN) substrate is injected with magnesium as a p-type dopant. The GaN substrate undergoes preheating through irradiation with light from halogen lamps in an atmosphere containing nitrogen and hydrogen, and further undergoes heating to a high temperature for a super-short time through irradiation with flashes of light from flash lamps. Heating the GaN substrate in the atmosphere containing nitrogen and hydrogen complements removed nitrogen, thus preventing nitrogen shortage. Such a heating process also enables heat treatment while supplying hydrogen to the GaN substrate. The heating process further enables crystal defects in the GaN substrate to be recovered. With these effects, the p-type dopant injected into the GaN substrate is activated with high efficiency.

Method for fabricating p-type gallium nitride semiconductor and method of heat treatment

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 semiconductor wafer serving as a treatment target has a stack structure in which a high-dielectric-constant gate insulating film is formed on a silicon base material with an interface layer film of silicon dioxide sandwiched therebetween, and a metal gate electrode containing fluorine is further formed thereon. A heat treatment apparatus radiates flash light from a flash lamp to the semiconductor wafer in an atmosphere containing hydrogen to carry out heating treatment for an extremely short period of time of 100 milliseconds or less. As a result, diffusion of nitrogen contained in the metal gate electrode is inhibited, at the same time, only the fluorine is diffused from the high-dielectric-constant gate insulating film to an interface between the interface layer film and the silicon base material to reduce an interface state, and reliability of the gate stack structure can be improved.

Manufacturing method of high-dielectric-constant gate insulating film of semiconductor device

A PSG film, which is a silicon dioxide thin film containing phosphorus as a dopant, is formed on the surface of a semiconductor wafer. The semiconductor wafer having the PSG film formed thereon is kept at a predetermined heating temperature by light radiation from halogen lamps in the atmosphere containing hydrogen for 1 second or longer, so that the dopant is diffused from the PSG film into the surface of the semiconductor wafer. In addition, the flashing light is radiated to the semiconductor wafer for the radiation time shorter than 1 second to heat the surface of the semiconductor wafer to the target temperature so as to activate the dopant. When the PSG film is heated in the atmosphere containing hydrogen, a diffusion coefficient of the dopant contained in the PSG film becomes high; therefore, the dopant can be efficiently diffused from the PSG film into the semiconductor wafer.

Dopant introduction method and thermal treatment method

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.

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.

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Kyoto, Japan

Takayuki Aoyama