JP2608728B2 - Silicon single crystal pulling equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Object of the Invention [Industrial Application Field] The present invention relates to a silicon single crystal pulling apparatus, and in particular, by supplying a preheated inert gas to a heat treatment furnace. The present invention relates to a silicon single crystal pulling apparatus which saves electric power consumed in a heat treatment furnace and shortens a time required for melting a silicon material.

[Prior Art] Conventionally, as this kind of silicon single crystal pulling apparatus, one that supplies an inert gas at normal temperature to a heat treatment furnace in a reduced pressure state has been proposed.

[Problems to be Solved] However, in the conventional silicon single crystal pulling apparatus, since the inert gas removes heat from the silicon material melted in the heat treatment furnace, power consumption in the heater for heating the silicon material is consumed. There is also a disadvantage that the melting of the silicon material requires a long time.

In order to eliminate these drawbacks, the present invention raises the temperature of the inert gas supplied to the heat treatment furnace in advance, thereby reducing power consumption in the heating heater and reducing the time required for melting the silicon material. In order to provide a silicon single crystal pulling apparatus in which the length is shortened.

(2) Configuration of the Invention [Means for Solving the Problems] A solution for the problems provided by the present invention is as follows: a heater for heating is provided around a crucible device in a heat treatment furnace, and silicon is used in the crucible device. In a silicon single crystal pulling apparatus obtained by melting a material and pulling up a silicon single crystal, an inert gas that has been heated in advance is supplied from above the crucible apparatus inside the heating heater to the crucible apparatus, and A silicon single crystal, characterized in that the supplied inert gas is exhausted from an exhaust pipe provided outside the heating heater, and the silicon material is melted by the crucible device by the heating heater. Lifting device ".

[Operation] The silicon single crystal pulling apparatus according to the present invention supplies an inert gas, which has been heated in advance, from above the crucible device inside the heating heater toward the crucible device, and supplies the supplied inert gas. Since the gas is exhausted from an exhaust pipe arranged outside the heater for heating and the silicon material is melted in the crucible device by the heater for heating, as a result, the power consumption in the heater for heating is reduced. It saves energy and shortens the time required to melt the silicon material.

EXAMPLES Next, the present invention will be specifically described with reference to the accompanying drawings.

FIG. 1 is a sectional view showing one embodiment of a silicon single crystal pulling apparatus of the present invention.

First, the configuration of an embodiment of the silicon single crystal pulling apparatus of the present invention will be described in detail.

10 is a silicon single crystal pulling apparatus of the present invention, heat treatment furnace 20
The heater 30 for heating is arranged inside the. The heating heater 30 is provided around a crucible device 50 described later. The heat-treating furnace 20 has a pull-up hole 22 formed at the upper bottom thereof and communicated with the pull-up chamber 21, and the pull-up hole 22 is formed above the crucible device. An exhaust pipe connected to a vacuum pump (not shown) serving as an exhaust means is provided at the lower bottom of the heat treatment furnace 20 and outside the heater for heating.
23 are arranged. The heating heater 30 has a cylindrical shape and is connected to an appropriate power supply (not shown), and the inside thereof is extended toward a rotary elevating device (not shown) below and outside the heat treatment furnace 20. A crucible device 50 fixed to one end of the connected rotary shaft 51 is arranged. The crucible device 50 includes a carbon crucible 52 fixed to a rotating shaft 51.
And a quartz crucible 54 disposed in the carbon crucible 52 and containing the silicon material 53. With respect to the silicon material 53 housed in the quartz crucible 54 and melted, a pull-up wire member 55 having a seed crystal (not shown) attached at the tip is provided through the pull-up hole 22 of the heat treatment furnace 20. It is hung from the lifting chamber 21.

Reference numeral 60 denotes an inert gas supply device, which is an inert gas supply pipe 62 that communicates between an inert gas source 61 and the upper end of the lifting chamber 21.
Is included. A heat exchange device 63 is provided around the inert gas supply pipe 62. Upstream opening 63 of heat exchange device 63
The high-temperature medium supplied to A gives heat to the inert gas in the inert gas supply pipe 62 while passing around the inert gas supply pipe 62 in the direction of arrow C, and then discharges from the downstream opening 63B. Is done.

Further, the operation of one embodiment of the silicon single crystal pulling apparatus of the present invention will be described in detail.

After the silicon material 53 is accommodated in the quartz crucible 54 of the crucible device 50 outside the heat treatment furnace 20 , the crucible device 50 is inserted into the inside of the heat treatment furnace 20 from below by a rotary elevating device (not shown). After that, exhaust means (not shown)
The heat treatment furnace 20 is evacuated in the direction of arrow A through the exhaust pipe 23 until the heat treatment furnace 20 reaches 10 to 25 Torr, and an inert gas such as argon is supplied from the inert gas supply device 60 through the pulling chamber 21 and the pulling hole 22. While supplying the gas in the direction of arrow B, an appropriate voltage is applied from an appropriate power supply (not shown) to the heating heater 30 while rotating the crucible device 50 by the rotary elevating device via the rotary shaft 51. Initially, the crucible device 50 is heated by the inert gas and the heater 30, and the temperature rises. And finally heater 30 for heating
However, the silicon material 53 contained in the quartz crucible 54 of the crucible device 50 is heated and melted. At this time, the inert gas is drawn from the inert gas source 61 by the inert gas supply pipe 62.
Since the silicon material 53 is heated to a desired temperature by the heat exchange device 63 when being transferred toward the upper end portion of the silicon material 53, the silicon material 53 is efficiently heated and melted.

When the silicon material 53 has been sufficiently melted, the lifting chamber
The pull-up wire member 55 is hung from the heat treatment furnace 20 through the pull-up hole 22 of the heat treatment furnace 20 , and the seed crystal attached to the tip thereof is immersed in the Siligon material 53, and then slowly pulled up. Along with this, a silicon single crystal 56 grows and is formed, and is pulled up to the pulling chamber 21 through the pulling hole 22.

In the silicon single crystal pulling apparatus 10 of the present invention, since the temperature of the inert gas (for example, argon gas) supplied from the pulling chamber 21 to the inside of the heat treatment furnace 20 is raised to a desired temperature, the heating heater 30 Can reduce power consumption.

In order to further understand the operation of the silicon single crystal pulling apparatus 10 of the present invention, specific numerical values will be described.

(Embodiment) In the silicon single crystal pulling apparatus 10 of the present invention shown in FIG. 1, the inside of the heating furnace 20 is depressurized through the exhaust pipe 23, and the pulling chamber 21 and the pulling chamber 21 are pulled from the inert gas supply apparatus 60. While supplying 150 ° C. argon gas at 15 Torr through the upper hole 22,
A voltage of 46 volts is applied to the heater 30 for heating to 1640
When an ampere current was applied, 30 kg of polysilicon or silicon material 53 contained in a quartz crucible 54 was removed.
Melting was possible in 2.5 hours.

After the silicon material 53 has been melted, the rotation speed of the rotary shaft 51 is appropriately selected while the supply of argon gas is continued, and the seed crystal is pulled up by the pulling wire member 55 to have a diameter of 5 inches (12.7 cm). ) Silicon single crystal 56 was grown.

At this time, the electric power consumed by the heating heater 30 is 75 kw.
It was time.

(Comparative example) The example was repeated except that the temperature of the argon gas supplied from the inert gas supply device 60 into the heat treatment furnace 20 was 25 ° C.

The time required from when the voltage was started to be applied to the heater 30 to when the polysilicon, that is, the silicon material 53 was melted, was 4 hours.

The electric power consumed by the heater 30 was 90 kw.

According to the present invention, in particular, the heater 30
And the melting time of the silicon material 53 can be shortened.

In the above description, the heat exchange device 63 is used as a means for raising the temperature of the inert gas.However, the present invention is not limited to this, and other appropriate heating devices may be used if desired. Good.

Further, the crucible device 50 is rotated by the rotating shaft 51, but the present invention is not limited to this,
If desired, the rotary shaft 51 may be removed.

(3) Effect of the Invention As is clear from the above description, the silicon single crystal pulling apparatus according to the present invention directs an inert gas, which has been heated in advance, from above the crucible apparatus inside the heating heater to the crucible apparatus. Supplying, and exhausting the supplied inert gas from an exhaust pipe arranged outside the heating heater,
Since the silicon material is melted by the crucible device by the heater for heating, there is an effect that (i) the heat taken from the molten silicon material can be reduced, and (ii) power consumption in the heater for heating (Iii) It has the effect of shortening the time required for melting the silicon material.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention. 10 Silicon single crystal pulling device 20 Heat treatment furnace 21 Pulling chamber 22 Pulling hole 23 Exhaust pipe 30 Heating heater 50 Crucible device 51 Rotating shaft 52 Carbon crucible 53 Silicon material 54 Quartz crucible 55 Pull-up wire member 60 Inert gas supply device 61 Inert gas source 62 Inert gas supply tube 63 Heat exchange device 63A …… Upstream opening 63B …… Downstream opening

 ──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-59-8694 (JP, A) JP-A-58-32100 (JP, A) JP-A-49-15366 (JP, A) JP-A 60-86 77115 (JP, A)

Claims (1)

(57) [Claims] 1. A silicon single crystal pulling apparatus comprising a heating heater disposed around a crucible device in a heat treatment furnace and melting a silicon material by the crucible device to pull up a silicon single crystal. Supplying a heated inert gas to the crucible device from above the crucible device inside the heating heater,
And an inert gas supplied is exhausted from an exhaust pipe provided outside the heater for heating, and the silicon material is melted in the crucible device by the heater for heating. Crystal pulling device.