Mitsubishi Materials Corporation

Mitsubishi Materials Silicon Corporation

Sumco Corporation

Research Development Corporation of Japan

Zaidan Hojin Handotai Kenkyu Shinkokai

Zag Ltd.

Mitsubishi Materials Quartz Corporation

Mitsubishi Materials Sillcon Corporation

Takashi Atami

Hisashi Furuya

Hiroaki Taguchi

Michio Kida

Masakazu Yamazaki

Michio Yanaba

Masanori Fukui

Ken Hamada

Shuichi Inami

Koichi Sassa

Keiji Shirata

Takuya Yotsui

Daisuke Wakabayashi

Masao Saitoh

A single crystal pulling apparatus comprises: a chamber; a crucible disposed within the chamber for containing a melt; a water-cooling means disposed within the chamber in such a manner as surrounding a single crystal pulled up from the melt in the crucible; water piping for feeding cooling water to and discharging the same from the water-cooling means; and supporting arms connected to the chamber for supporting the water-cooling means, wherein the supporting arms are disposed between the single crystal and the water piping. According to this configuration, the supporting arms can prevent the water piping from being damaged in the event of fall and collapse of the single crystal due to failure of the seed neck portion or in the event of rupture of the single crystal due to thermal stress, for instance.

Single crystal pulling apparatus

An improvement in the safety, ease and speed with which the operation of attaching a crucible 1 to a support base 10 of a single crystal pulling apparatus can be completed is provided. With the method of attaching the crucible 1 to the support base 10, the support base 10 is divided into a support base bottom portion 11 and a support base drum portion 12 which is fitted to the bottom portion 11, and the crucible 1 is mounted on the support base bottom portion 11. The support base 10 is then assembled by fitting the support base drum portion 12 to the support base bottom portion 11.

Methods for crucible attachment to support base of single crystal

The invention relates to a single crystal pulling apparatus comprising; an outer crucible 11 positioned inside a chamber (gas tight container) 2, for storing a semiconductor melt 21, and an inner crucible 30 comprising a cylindrical partition body, mounted inside the outer crucible 11 to form a double crucible, and wherein a single crystal of semiconductor 26 is pulled from the semiconductor melt 21 stored inside the inner crucible 30. With this arrangement, the inner crucible 30 is made from quartz and comprises an inside layer A, an outside layer C, and an intermediate layer B which lies between the inside layer A and the outside layer C, and the intermediate layer B is made from quartz with a larger gas bubble content than the quartz which makes up the inside layer A and the outside layer C of the inner crucible 30.

A single crystal pulling method employing; a gas tight container, a double crucible for storing a semiconductor melt inside the gas tight container comprising an inter-connected outer crucible and inner crucible, and a source material supply tube suspended from an upper portion of the gas tight container and positioned so that a granulated or powdered source material can be added from a lower end opening thereof to the semiconductor melt inside the outer crucible, with the source material being injected into the source material supply tube together with an inert gas flowing towards the enclosed container, characterized in that said source material is injected under conditions where the flow rate N (1/min.multidot.cm.sup.2) of the inert gas is within the range 0.0048P+0.0264&lt;N&lt;0.07P, where P (Torr) is the internal pressure inside said gas tight container.

Single crystal pulling method and apparatus for its implementation

A single crystal pulling apparatus wherein a semiconductor melt is stored in an outer crucible, and a cylindrical inner crucible which acts as a partition body, is mounted inside the outer crucible to thus form a double crucible, and a single crystal of semiconductor is pulled from the semiconductor melt inside the inner crucible. The inner crucible contains a communicating portion, which is formed when the double crucible is formed, for allowing flow of the semiconductor melt into the inner crucible, and the communicating portion incorporates an arrangement for removal of gas bubbles which have adhered to the communicating portion.

A single crystal pulling apparatus comprising: a gas tight container, a double crucible for storing a semiconductor melt inside the gas tight container comprising an outer crucible and an inner crucible which are connected at a lower edge, and source material supply means for adding source material to the semiconductor melt at a position between the outer crucible and the inner crucible, characterized in that a flow restriction member is provided inside the semiconductor melt region between the outer crucible and the inner crucible for restricting the flow of the semiconductor melt.

The principal construction of a single crystal pulling apparatus involves a chamber (gas tight chamber) inside of which is a double crucible 3 for storing a semiconductor melt 21, comprising an outer crucible 11 and an inner crucible 12 communicated with each other, and a source material supply tube 5 suspended from an upper portion of the chamber, and positioned so that granular source material 8 can be introduced from a lower end opening 5a thereof into the semiconductor melt 21 between the outer crucible 11 and the inner crucible 12. An incline portion 13 is provided at a lower end of the source material supply tube 5 on the inner crucible 12 side, for introducing source material 8 discharging from the lower end opening 5a to the semiconductor melt 21 in the vicinity of the side wall of the outer crucible 11. The entry point of the source material 8 is as far as possible from the inner crucible 12, and close to the outer wall of the outer crucible 11, and hence the added source material 8 is melted rapidly by heat from a heater surrounding the outer crucible 11, and any gas bubbles generated as a result of the introduction of the source material 8, are unlikely infuse into the inner crucible 12.

The invention is directed to preventing meltdown of conductive metal electrodes 5, 5 used to supply current to a heater 104 of a crucible 103. A single crystal pulling apparatus comprises: the heater 104 which encircles the crucible 103, and the pair of electrodes 5, 5, respectively threaded to a pair of graphite intermediate electrodes 6 of the heater 104, and a voltage source 9 for supplying power to the pair of electrodes 5, 5. A switch 11 switches the power on and off. A watthour meter 10a, continuously measures the current flowing through the heater 104. Investigation by the present inventors showed that in the case of a crack 8 in a lower portion of the intermediate electrode 6, minute fluctuations occurred in the measured value of the current, arising from an electric discharge phenomena in the crack 8 prior to meltdown of the electrodes 5, 5. Therefore, if fluctuations in the electric current measured by the wattmeter 10a are outside of a tolerance range, the controller 12 switches off the switch 11, thus interrupting power to the electrodes 5, 5, and preventing meltdown of the electrodes 5, 5.

Apparatus for preventing heater electrode meltdown in single crystal

A method of growing a single crystal of semiconductor using a CZ growth technique, having a step (0&lt;t&lt;t1) wherein a single crystal of semiconductor is pulled while a source material is supplied continuously to maintain a constant amount of semiconductor melt, and a step (t2&lt;t&lt;t3) wherein the supply of source material is halted, and the single crystal of semiconductor is pulled using residual melt from the first step.

Single crystal growth method

An annular member hoist apparatus which lifts an annular member and carries and positions the annular member at a predetermined location by a carrier apparatus fitted with an elevator mechanism, including a suspension member suspended from the elevator mechanism, and a plurality of support arms which extend out radially in a horizontal plane from the suspension member. Each of the support arms has an engagement tip portion for supporting the annular member from inside the annular member.

Hoist apparatus for annular member

The present invention provides an improved single crystal pulling apparatus for pulling a single crystal semiconductor such as silicon or gallium arsenide. The apparatus of the present invention comprises a gas tight container, a crucible which is disposed inside the container, a heater, and a pair of coils to apply a cusp magnetic field in the semiconductor melt. The crucible is separated into two regions by a cylindrical partition body, and an outside region is used to supply source material and to melt the source material and an inside region is used for pulling up the single crystal. The inside and outside regions are communicated with the communication passage provided at the bottom of the partition body. Electrical currents in opposing directions are applied to a pair of coils for generating in the melt a cusp magnetic field which includes a vertical portion and a horizontal portion relative to the crucible. By positioning the vertical portion of the cusp magnetic field at the position of the communication passage and the horizontal portion below the semiconductor melt, the flow rate of the melt passing through the communication passage is reduced and the convection within the melt is suppressed. Consequently, high quality semiconductor single crystals can be obtained.

Growing community of inventors

Tokyo, Japan

Takashi Atami