Shin-etsu Handotai Co., Ltd.

Shin-etsu Chemical Co., Ltd.

Kenji Araki

Atsushi Iwasaki

Masahiko Baba

Hideto Kato

Izumi Fusegawa

Eiichi Iino

Takafumi Ueda

Susumu Sonokawa

Masahiko Urano

Kouji Mizuishi

Toshiharu Uesugi

Kouji Kitagawa

Akiho Maeda

Hideo Okamoto

A desolvation unit performs desolvation by heating after a sample solution is turned to sample mist by a nebulizer. A sample gas that contains the desolvated sample mist and a carrier gas is introduced through a sample introduction tube to a plasma torch. An addition unit for adding, to the sample introduction tube, a water-containing gas is provided. The addition unit includes a container that contains ultrapure water, a gas tube for introducing the carrier gas into the ultrapure water to cause bubbling, and a gas tube for adding the water-containing gas, to the sample introduction tube. The plasma torch generates an inductively coupled plasma under the condition that supplied power is set to a range of 550 W to 700 W. Generation of interfering molecule ions due to an element having a high ionization potential is inhibited when an element in a sample ionized by the plasma is analyzed.

Sample analysis method and sample introduction device

From a heat-curable photosensitive composition comprising a cresol and/or xylenol novolac resin which has been partially 1,2-naphthoquinonediazido-4- or 5-sulfonate esterified and having a weight average molecular weight of 1,000-10,000, an epoxy compound, and a solvent therefor, a pattern featuring improved solvent resistance and heat resistance can be formed at a high sensitivity and resolution by a simple process. The pattern is suitable as an interlayer insulating film for use in thin-film magnetic heads.

Heat-curable photosensitive compositions

A method of producing a single crystal by Czochralski method by contacting a seed crystal with a melt in a crucible, and then pulling it slowly to grow a single crystal ingot, wherein a pulling condition is controlled according to a cumulative time of use of a heater surrounding the crucible. The pulling conditions to be controlled may induce the relative position of the heater and the crucible, the number of rotations of the crucible, the number of rotations of the crystal, or an atmosphere pressure in the furnace and a gas volume of flowing. Also described is a method of producing a silicon single crystal by CZ method wherein a dispersion of impurity concentration in the crystal can be reduced, and a single crystal can be produced stably.

Method for producing a silicon single crystal

A novel device for producing a single crystal by the CZ or MCZ method is provided, which comprising a crucible for containing silicon melt therein, a wire reel and a wire for pulling a single crystal, a motor and a rotation shaft for rotating the crucible, a speed change device being inserted between the motor and the rotation shaft, and, if necessary, a magnetic field generator, by which the magnetic field is applied to the melt. According to the device for producing a single crystal, the rotation accuracy of a crucible can be improved, so that the concentrations of impurities in the pulled single crystal can be highly precisely controlled.

Device for producing a single crystal

The method automatically controls the growing of a single-crystal neck portion by the CZ method. The speed of pulling up the crystal is adjusted so that the crystal diameter control deviation becomes closer to zero. Combinations of the crystal diameter control deviation .DELTA.D being large or small and the pulling-up speed V being high or low are employed as fuzzy inference conditions. According to such conditions, a correction value for the power supplied to a melt heater 18 is calculated, based on the fuzzy inference.

Automatic control method for growing single-crystal neck portions

Used in a Si crystal pulling apparatus using the Czochralski method, to lower the concentration of oxygen in the Si single crystal without increasing the production cost and to make the concentration substantially even all over the Si single crystal. The crystal 36 is produced by disposing a straightening tube 40 concentrically with and above a quartz crucible 22, letting inert gas flow down through the tube, dipping a seed crystal in Si molten liquid 28 in the quartz crucible and then pulling the seed crystal up. The concentration of oxygen in the Si single crystal is adjusted by controlling the distance H between the surface of the Si molten liquid and the bottom end of the straightening tube in accordance with the pull-up length Y or the pull-up time from a certain growth point of the crystal.

Method of adjusting concentration of oxygen in silicon single crystal

Used in an apparatus for pulling a Si single crystal 36 up from Si molten liquid 35 by using the Czochralski method. In order to produce a Si single crystal having a desired quality, the diameter of the Si single crystal is controlled by controlling the pull-up speed of the Si single crystal, the sum of a reference temperature set value T.sub.B (X), which is a function of a pull-up distance X of the Si single crystal from a certain growth point, and a value proportional to a diameter deviation .DELTA.D is regarded as a reference temperature, and electric power supplied to a heater (24) for heating the Si molten liquid is controlled so that the temperature of the vicinity of the heater is equal to the reference temperature. In order to easily and quickly set the temperature pattern, various operational data in producing a Si single crystal is automatically collected and stored in a magnetic memory disk (82) corresponding to quality data of the Si single crystals which have been produced, data similar to the quality of a Si single crystal to be produced is retrieved from the stored data, an operator selects the most similar data, the selected operational data is displayed in a display unit (80), and the operator sets the reference temperature pattern T.sub.B (X) on a screen of the display unit by using a mouse (78).

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Annaka, Japan

Kenji Araki