Shin-etsu Handotai Co., Ltd.

Shin-estu Handotai Co., Ltd.

Masahiko Urano

Atsushi Ozaki

Eiichi Iino

Ryoji Hoshi

Tomohiro Kakegawa

Hideki Nakano

Izumi Fusegawa

Michiaki Oda

Yoshihiro Hirano

Isamu Harada

Yasushi Nakamura

Masanori Kimura

Makoto Iida

Kiyotaka Takano

Shozo Muraoka

Susumu Sonokawa

Koji Mizuishi

Kouji Mizuishi

Kosei Sugawara

Kenji Araki

Kouji Kitagawa

Seiichiro Ohtsuka

Seiichiro Otsuka

Naoki Masuda

Katsuyuki Kitagawa

Katsuhiro Yoshida

A single crystal pulling apparatus including: a remelting detection apparatus which detects that remelting of a lower end portion of the semiconductor single crystal is completed from a change in weight of the semiconductor single crystal when the lower end portion of the semiconductor single crystal is immersed in the melt to be remolten by using the wire; and a lowermost end detection apparatus which detects a lowermost end of the semiconductor single crystal from a position where no current flows between the semiconductor single crystal and the melt when the semiconductor single crystal is taken up with the use of the wire while applying a voltage between the semiconductor single crystal and the melt by applying a voltage between the crucible and the wire.

Semiconductor single crystal pulling apparatus and method for remelting semiconductor single crystal using this

A method of charging raw material, includes: storing the material in a recharge tube including a quartz cylinder for storing the material and a conical valve for opening or closing an opening at a lower end of the cylinder; installing the recharge tube storing the raw material in a chamber; and feeding the raw material stored in the recharge tube into the crucible by locating the recharge tube and crucible such that a distance between the lower end of the recharge tube and raw material or melt in the crucible ranges from 200 to 250 mm, and lowering the conical valve to open the opening while simultaneously lowering the crucible such that a ratio CL/SL of the lowering speed of the crucible to the lowering speed of the conical valve ranges from 1.3 to 1.45. The method can inhibit damage of the quartz crucible and recharge tube.

Method of charging raw material, method of manufacturing single crystals, and single crystal manufacturing apparatus

A method for measuring a distance between a lower end surface of a heat insulating member and a surface of a raw material melt with a reference reflector provided at a lower end of the heat insulating member which is located above the surface of the raw material melt when a silicon single crystal is pulled up by a Czochralski method while a magnetic field is applied to the raw material melt in a crucible is disclosed. The method comprises the steps of contacting a projection made of quartz, silicon or carbon with the surface of the raw material melt, the projection being longer that the reference reflector and having a length corresponding to an initial distance; electrically detecting the contact between the projection and the melt surface, and observing an initial location of a mirror image of the reference reflector by a camera when the distance between the lower end surface of the heat insulating member and the surface of the raw material melt has been adjusted so as to be the initial distance, the mirror image being reflected on the surface of the raw material melt; and while pulling the silicon single crystal, measuring a travel distance of the mirror image from the initial location by the camera and calculating the distance between the lower end surface of the heat insulating member and the surface of the raw material melt from the initial travel distance of the mirror image.

Method for measuring distance between lower end surface of heat insulating member and surface of raw material melt and method for controlling thereof

A method for measuring a distance between a lower end surface of a heat shielding member including a criterion reflector inside a concavity on the lower end surface and a surface of a raw material melt includes: a silicon single crystal is pulled by the Czochralski method while a magnetic field is applied to the raw material melt in a crucible, measuring the distance between the lower end surface of the heat shielding member and the surface of the raw material melt and observing a position of a mirror image of the criterion reflector with a fixed point observation apparatus; and measuring a movement distance of the mirror image with the apparatus and calculating the distance between the lower end surface of the heat shielding member and the surface of the raw material melt from the movement distance of the image and the measured distance.

Method for measuring and controlling distance between lower end surface of heat shielding member and surface of raw material melt and method for manufacturing silicon single crystal

The present invention provides an apparatus for producing single crystals according to the Czochralski method, the apparatus including a chamber that can be divided into a plurality of chambers; at least one of the plurality of divided chambers having a circulating coolant passage in which a circulating coolant for cooling the chamber circulates; and measuring means that respectively measure an inlet temperature, an outlet temperature, and a circulating coolant flow rate of the circulating coolant in the circulating coolant passage; the apparatus further including a calculating means that calculates a quantity of heat removed from the chamber and/or a proportion of the quantity of removed heat, from the measured values of the inlet temperature, outlet temperature, and circulating coolant flow rate; and a pulling rate control means that controls a pulling rate of the single crystal based on the resulting quantity of removed heat and/or the resulting proportion of the quantity of removed heat. The invention also provides a method for producing single crystals using the apparatus. Thus, an apparatus and a method for producing single crystals are provided for producing single crystals while easily stabilizing the crystal quality.

Apparatus and method for producing single crystals

The present invention is a method for determining a relative distance between a reference member placed above a melt surface and the melt surface upon pulling a silicon single crystal out of a raw material melt in a crucible by a CZ method characterized by at least: pulling the silicon single crystal applying a magnetic field; taking a picture of a real image of the reference member and a mirror image of the reference member reflected on the melt surface with a detector; processing the picture taken of the real image and the mirror image of the reference member as different pictures by separating the picture taken; and calculating the relative distance between the real image and the mirror image of the reference member from the processed pictures to determine the relative distance between the reference member and the melt surface.

Method for determining distance between reference member and melt surface, method for controlling location of melt surface using the same, and apparatus for production silicon single crystal

An apparatus and a method capable of automatically adjusting an initial position of the surface of a melt without an operator are provided. In a single crystal puller using a wire as a suspender for a seed crystal for growing a single crystal of silicon or the like according to the CZ method, a reference position of the seed crystal is detected, the wire is unwound to lower the end of the wire to a position higher by a distance W-X from the reference position and then pulled upward above said reference position to correct the wire for an extension due to the weight of a single crystal attached thereto. Also, the wire is left above a melt for about ten minutes to provide a constant amount of extension to the wire due to heat of the melt. These operations are automatically performed.

Method for adjusting initial position of melt surface

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

An apparatus and a method capable of automatically adjusting an initial position of the surface of a melt without an operator are provided. In a single crystal puller using a wire as a suspender for a seed crystal for growing a single crystal of silicon or the like according to the CZ method, a reference position of the seed crystal is detected, the wire is unwound to lower the end of the wire to a position higher by a distance W-X from the reference position and then pulled upward above said reference position to correct the wire for an extension due to the weight of a single crystal attached thereto. Also, the wire is left above a melt for about ten minutes to provide a constant amount of extension to the wire due to heat of the melt These operations are automatically performed.

Apparatus for adjusting initial position of melt surface

In a crystal pulling method in which a growing single crystal is initially pulled by a seed chuck and subsequently pulled by lifting jig in the middle of the pulling operation, the speed Va of the seed chuck relative to the lifting jig is decreased, while the rising speed Vb of the lifting jig increases, from a first point where switching of the pulling mechanism from the seed chuck to the lifting jig is started. The total speed Vt=Vb+Va is constantly maintained at a desired pulling speed V up to a third point where the shifting of the load from the seed chuck to the lifting jig is started. Subsequently, the total speed Vt is made less than the desired pulling speed V from the third point where the shifting of the load from the seed shuck to the lifting jig is started. This enables accurate growth of a crystal.

Crystal pulling method

A method and an apparatus for pulling a single crystal are disclosed. A first neck portion, a convex portion, and a second neck portion are formed in this order under a seed crystal held by a seed chuck, and subsequent to the second neck portion, a single crystal having a diameter-expanding portion and a straight cylindrical portion is formed. Lifting holders are brought around and in proximity to the second neck portion when the second neck portion rises to a predetermined position during the pulling by the seed chuck. The single crystal and the lifting holders are moved relative to each other in the vertical direction to thereby bring the convex portion into contact with the lifting holders in a resting manner, so that part of a load borne by the seed chuck is shifted to the lifting holders. Subsequently, the pulling operation is performed by the lifting holders. Accordingly, a single crystal having a larger weight can be pulled safely while maintaining high quality.

Crystal pulling methods and apparatus

A crystal pulling apparatus is disclosed which employs the Czochralski method. The crystal pulling apparatus is operated while a heater for heating a material melt in a crucible is controlled by the main controller of a main system. When maintenance of a heating state is disabled for some reason, a relay of a signal changeover circuit is switched so as to maintain the heating state under control of the backup controller of a backup system, thereby maintaining the material melt in a molten state. Thus, even when it becomes impossible for the main system to heat the material melt within the crucible, the material melt can be prevented from becoming solidified.

Crystal pulling apparatus

An apparatus for producing a semiconductor single-crystal grown by the Czochralski method includes a reference reflector disposed at the lower end of a gas rectifying tube, first and second optical systems disposed above the reference reflector for changing the direction of propagation of light from the horizontal to the vertical, and vice versa, a first position sensor composed of a first light source for emitting a light beam in a horizontal direction toward the first optical system, and a first photosensitive member which receives a reflection light reflected from the melt surface in a crucible, a second position sensor composed of a second light source for emitting a light beam in a horizontal direction toward the second optical system, and a second photosensitive member which receives a reflection light reflected from the reference reflector. With this construction, the distance between the gas rectifying tube and the melt surface can be detected and maintained constant throughout the crystal growth process with the result that the crystal quality, especially the concentration of dopant and impurities, such as oxygen and carbon, is uniform.

Method and apparatus for producing a Czochralski growth semiconductor

The present invention provides control of single crystal growth after the recovery from power failure when controlling crystal growth in an automatic mode. A source voltage is supplied to a controller 70 through a no-break power supply 62. At the time of recovery from power failure, the controller continues the automatic operation mode with the same control output as that stored when power failure is detected (84, 85) if the power failure time t is t .ltoreq.t.sub.1 (for example, 1 second), switches the control mode to the manual control mode with the same control output as that stored when the power failure is detected (86, 87) if t.sub.1 &lt;t.ltoreq.t.sub.2 (for example, 5 seconds), stops the crystal growth operation and switches the control mode to the manual control mode (88, 89) if t.sub.2 &lt;t.ltoreq.t.sub.3 (for example, 600 seconds), and separates the grown crystal from a melt 22 by upwardly moving the crystal and upwardly moves a crucible 16 (90) if t&gt;t.sub.3.

Single crystal rod pull-up growing apparatus

A single crystal pulling apparatus having a wire which is used to pull a crystal is provided with a novel wire vibration prevention mechanism. The wire vibration prevention mechanism includes wire restriction devices which restrict the movement of the wire to movement in the vertical direction. The wire restriction devices may be mechanically driven in the horizontal direction in order to center the pulled crystal. The wire restriction devices are driven by pneumatic air cylinders. Use of the wire vibration prevention mechanism avoids the formation of deformed growth of the pulled crystal and thus reduces the occurrence of dislocations in the pulled crystal.

Growing community of inventors

Takasaki, Japan

Masahiko Urano