KR20170031885A

KR20170031885A - Ingot grower

Info

Publication number: KR20170031885A
Application number: KR1020150129405A
Authority: KR
Inventors: 이창윤; 성진규
Original assignee: 주식회사 엘지실트론
Priority date: 2015-09-14
Filing date: 2015-09-14
Publication date: 2017-03-22
Also published as: KR101723740B1

Abstract

The present invention relates to an ingot growing apparatus capable of precisely measuring a moment when a measuring rod and a silicon melt contact with each other.
The present invention relates to a crucible comprising an electric conductor containing a silicon melt; A measuring rod provided on the upper side of the crucible so as to be able to move up and down and made of an electric conductor in contact with the silicon melt surface; And a sensing circuit connected to the measuring rod and sensing an instantaneous current as the measuring rod comes into contact with the silicon melt surface.

Description

Ingot grower

The present invention relates to an ingot growing apparatus capable of precisely measuring a moment when a measuring rod and a silicon melt contact with each other.

In general, in order to manufacture a silicon wafer, monocrystalline silicon must be grown in an ingot form, and a czochralski (CZ) method can be applied.

Such a silicon single crystal growth apparatus includes a surface of a silicon melt and a heat shield member so that heat radiated from the heater can not be transmitted to the silicon single crystal ingot.

In the case of installing a heat shield member, a gap is maintained between the lower end of the heat shield member and the surface of the silicon melt. This gap is called a melt gap, and the quality and productivity of the silicon single crystal ingot are increased The melt gap must be kept constant for the purpose of

Accordingly, when the melting process of the silicon melt is completed, the lower end (e.g., the measuring rod) of the heat shield member and the surface of the silicon melt are brought into contact with each other to set the melt gap or measure the melt gap, Can be measured.

Korean Patent Laid-Open Publication No. 2014-0035625 discloses scale loading in a reflector of an ingot growing apparatus which is filled with a colored filler on the inside of a quartz tube in order to improve the accuracy of melt-gap measurement.

Korean Patent Laid-Open Publication No. 2014-0097834 discloses a measuring rod for a single crystal ingot growing apparatus including a negative or embossed indication portion on the lower surface.

However, when the operator directly contacts the above-mentioned measuring rod with the silicon melt surface at the initial stage of the process, the initial melt gap is set by adjusting the height of the crucible containing the silicon melt, Measure the melt gap.

According to the conventional technology, the depth at which the measuring rod and the silicon melt surface are in contact with each other can be varied, thereby causing an error of 1 to 2 mm in the initial gap set for each worker. Further, have.

It is an object of the present invention to provide an ingot growing apparatus capable of precisely measuring a moment when a measuring rod and a silicon melt are in contact with each other.

The present invention relates to a crucible comprising an electric conductor containing a silicon melt; A measuring rod provided on the upper side of the crucible so as to be able to move up and down and made of an electric conductor in contact with the silicon melt surface; And a sensing circuit connected to the measuring rod and sensing an instantaneous current as the measuring rod comes into contact with the silicon melt surface.

The ingot growing apparatus according to the present invention can precisely measure the moment when the measuring rod and the silicon melt contact with each other by applying a sensing circuit for sensing the instantaneous current as the measuring rod comes into contact with the silicon melt surface.

Therefore, the position of the measuring rod and the silicon melt can be precisely measured at the moment of contact, thereby adjusting the height of the crucible to accurately set the initial gap and also improving the quality of the ingot.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view showing an example of an ingot growing apparatus of the present invention. Fig.
Fig. 2 shows an example of a sensing circuit applied to Fig. 1; Fig.

Hereinafter, the present embodiment will be described in detail with reference to the accompanying drawings. It should be understood, however, that the scope of the inventive concept of the present embodiment can be determined from the matters disclosed in the present embodiment, and the spirit of the present invention possessed by the present embodiment is not limited to the embodiments in which addition, Variations.

FIG. 1 is a view showing an example of an ingot growing apparatus of the present invention, and FIG. 2 is a diagram showing an example of a sensing circuit applied to FIG.

1 and 2, the ingot growing apparatus of the present invention includes a chamber 110, a crucible 120, a crucible supporting portion 130, a heater 140, a heat insulating member 150, A member 170, a heat shield member 180, a measuring rod 190, and a sensing circuit 200. [

The chamber 110 provides an enclosed space for growing the ingot as well as for growing the ingot and includes a body chamber 111, a dome chamber 112, a pull chamber 113 And a view port (not shown) for observing the inside of the chamber 110 is provided on the upper side.

Further, a camera such as a CCD or the like will measure the melt gap, which is the distance between the measuring rod and the silicon melt, which will be described later, through the view port.

The crucible 120 is disposed inside the chamber 110 and is composed of a quartz inner peripheral portion 121 that does not affect the purity even when the silicon melt is contained therein and an outer peripheral portion 122 made of graphite on the outer side thereof.

The crucible supporting part 130 is provided at the lower center of the crucible 120 and can drive the crucible 120 to be able to rotate and elevate.

The heater 140 is disposed around the crucible 120 at a predetermined interval to heat the crucible 120.

The heat insulating member 150 is provided on the inner wall of the chamber 110 so as to maintain a predetermined gap around the heater 140 so that the heat provided from the heater 140 flows out through the chamber 110 .

The elevating member 170 is installed to pass the upper surface of the chamber 110 so as to raise and lower the heat shielding member 180.

The elevating member 170 is made of a graphite material which is an electrical conductor and is provided with a predetermined insulating member 171 capable of blocking an electrical connection between the chamber 110 and the elevating member 170 .

The heat shielding member 180 is positioned so as to surround the ingot which is pulled up from the silicon melt contained in the crucible 120. The upper end of the heat shielding member 180 is located above the heat insulating member 150 And can be lifted up and down by the elevating member 170. The elevating member 170 is disposed to hang on the crucible 120.

At this time, the heat shielding member 180 may be formed in a cylindrical shape having a smaller diameter from the upper side to the lower side, and may have a fixed sealed space between the inner and outer circumferential portions, or may be configured to circulate the cooling water. .

The heat shielding member 180 is also made of a graphite material that is an electrical conductor and has a predetermined insulating member 181 that can block the electrical connection between the heat insulating member 150 and the heat shield member 180. [ .

The measuring rod 190 is coupled to the lower end of the heat shield member 180 and is located in proximity to the silicon melt contained in the crucible 120. Of course, the measuring rod 190 is made of quartz (SiO ₂ ) material so as not to affect the yield because it is close to a high temperature silicon melt.

The measuring rod 190 may serve as a reference when measuring the melt gap, which is a distance between the heat shield member 180 and the silicon melt, and may be referred to as a scale rod do.

The sensing circuit 200 is configured to allow an instantaneous current to flow as the measuring rod 190 contacts the silicon melt surface. The sensing circuit 200 senses an instantaneous current flowing in the sensing circuit 200, It is judged that it is in contact with the melt surface.

The sensing circuit 200 may include a voltage 210 and a resistor 220 connected in series to connect the crucible supporter 130 and the elevation member 170, A sensing unit 230 connected to a line / rear end to sense a potential difference and an operation switch 240 provided between the voltage 210 and the resistor 220 to turn on / off.

Of course, the crucible 120, the crucible supporter 130, and the silicon melt are electrically connected to each other, and the elevation member 170, the heat shield member 180, and the measurement rod 190 are also electrically connected to each other And the sensing circuit 200 is installed so as to electrically connect the crucible supporter 130 and the elevator member 170 to each other.

Accordingly, when the measuring rod 190 comes into contact with the silicon melt surface at the initial stage of the process, an instantaneous current flows along the sensing circuit 200, and the sensing unit 230 senses The initial gap can be set by controlling the height of the crucible 120 on the basis of the sensed contact of the measuring rod 190 with the silicon melt surface by detecting the potential difference, The quality of the ingot can be improved by controlling the gap accurately.

However, when the measuring rod 190 contacts the silicon melt surface during the ingot growing step, an instantaneous current flows in the silicon melt, and the ionized elements in the silicon melt affect the quality of the ingot Lt; / RTI >

Accordingly, the operation switch 240 is turned on so that the sensing circuit 200 can be operated only at the initial stage of the process, while the operation switch 240 is not operated during the process, It is preferable to be turned off.

110: chamber 120: crucible
130: crucible supporting part 140: heater
150: Insulation 170: Lift member
180: heat shield member 190: measuring stick
200: sensing circuit

Claims

A crucible consisting of an electric conductor containing a silicon melt;
A measuring rod provided on the upper side of the crucible so as to be able to move up and down and made of an electric conductor in contact with the silicon melt surface; And
And a sensing circuit connected to the measuring rod and sensing an instantaneous current as the measuring rod comes into contact with the silicon melt surface.

The method according to claim 1,
A heat shield member made of an electric conductor provided to hang above the crucible and cooling a single crystal ingot grown from the silicon melt;
An elevating member connected to the upper side of the heat shielding member and composed of an electric conductor for elevating and lowering the heat shielding member; And
And a crucible supporting member provided below the crucible and supporting the crucible so that the crucible can be raised and lowered,
The measuring rod is fixed to the lower end of the heat shield member,
Wherein the sensing circuit is configured to connect the elevation member and the crucible supporting member.

3. The method of claim 2,
A heat insulating member provided between the chamber and the heater, the heat insulating member being capable of receiving the upper end of the heat shielding member; And
And an insulating member for cutting off electrical connection between the heat shield member and the heat insulating member.

3. The method of claim 2,
And an insulating member for disconnecting an electrical connection between the elevating member and the chamber.

3. The method of claim 2,
The heat shielding member, the elevating member and the crucible supporting member are made of graphite,
Wherein the measuring rod is made of quartz (SiO ₂ ) material.

6. The method according to any one of claims 1 to 5,
Wherein the sensing circuit comprises:
And an operation switch for turning on / off the instantaneous current.