KR102317425B1 - Silicon carbide grower having inner monitoring function - Google Patents

Abstract

A silicon carbide single crystal growth apparatus having an internal monitoring function is disclosed. In the silicon carbide single crystal growth apparatus having an internal monitoring function according to an embodiment of the present invention, a crucible filled with a deposition material for silicon carbide single crystal growth is disposed therein, and as the deposition material from the crucible is deposited, silicon a vacuum chamber forming a place where the carbide single crystal growth process is performed; and an internal monitoring unit coupled to the vacuum chamber from the outside of the vacuum chamber and monitoring a shape in which a silicon carbide single crystal grows.

Description

Silicon carbide single crystal growing device having an internal monitoring function {Silicon carbide grower having inner monitoring function}

The present invention relates to a silicon carbide single crystal growth apparatus having an internal monitoring function, and more specifically, because internal monitoring is possible, the shape of the silicon carbide single crystal growth without releasing the vacuum of the vacuum chamber or opening the crucible in the middle of the process It relates to a silicon carbide single crystal growing apparatus having an internal monitoring function, which can effectively check, thereby significantly reducing the occurrence of human, human, and material loss.

Silicon Carbide (SiC) is a wide-gap semiconductor having a wide forbidden gap in the range of 2.2 to 3.3 eV.

Since silicon carbide has excellent physical and chemical properties, it has been studied as an environment-resistant semiconductor material.

Silicon carbide wafers (SiC wafers), which are used in various fields such as power semiconductors, communication semiconductors, and LED products, have superior characteristics such as high temperature operation, high thermal conductivity, high dielectric breakdown field, and high band gap compared to normal silicon wafers. It is a material attracting attention as a next-generation semiconductor material with properties.

Such a silicon carbide wafer is manufactured by physical vapor deposition (PVT). That is, after making an ingot with silicon carbide, it is possible to make a silicon carbide wafer by slicing it.

The process temperature for growing silicon carbide by physical vapor deposition is approximately 2,100 to 2,400 °C. In order to provide such a temperature, an induction heater is mainly used.

In addition, a crucible (Graphite Crucible) is mainly used as a part in which the deposition material to which heat is applied is stored.

On the other hand, since the silicon carbide single crystal growth process according to the silicon carbide single crystal growth apparatus proceeds under vacuum conditions, a vacuum chamber is required to construct the apparatus.

Existing vacuum chambers include an upper chamber and a lower chamber, and a silicon carbide single crystal growth process is performed inside the upper chamber and the lower chamber.

However, in the case of the prior art, due to its structural limitations, the internal state of the crucible from the outside, that is, the shape (size, shape, etc.) in which the silicon carbide single crystal grows, etc. (size, shape, etc.) There is a problem that can cause a lot of time, human, and material loss in that it cannot be checked at all and can only be checked after growth is completed.

Korean Intellectual Property Office Application No. 10-2013-0097028

Therefore, the technical problem to be achieved by the present invention is that the shape of the silicon carbide single crystal growth can be effectively checked in the middle of the process without releasing the vacuum of the vacuum chamber or opening the crucible because internal monitoring is possible. It is to provide a silicon carbide single crystal growth apparatus having an internal monitoring function, which can significantly reduce the occurrence of human and material loss.

According to one aspect of the present invention, a crucible filled with a deposition material for silicon carbide single crystal growth is disposed therein, and a silicon carbide single crystal growth process is formed while the deposition material from the crucible is deposited. vacuum chamber; and an internal monitoring unit coupled to the vacuum chamber from the outside of the vacuum chamber and monitoring a shape in which the silicon carbide single crystal grows. can be

The vacuum chamber may be a plurality of vacuum chambers continuously connected to each other.

The internal monitoring unit may be a common internal monitoring unit that is commonly applied to the plurality of vacuum chambers and performs internal monitoring for all of the plurality of vacuum chambers.

The common internal monitoring unit may perform internal monitoring by the action of X-rays.

The common internal monitoring unit may include: an X-ray source disposed in one area of the vacuum chamber and transmitting X-rays into the vacuum chamber at the corresponding position; and a detector disposed on the opposite side of the X-ray source with the vacuum chamber interposed therebetween, and configured to receive and sense X-rays transmitted from the X-ray source.

The common internal monitoring unit may further include a unit moving part connected to the X-ray source and the detector, and moving the X-ray source and the detector to a plurality of the vacuum chambers.

The unit moving unit may include: a moving gantry disposed above the plurality of vacuum chambers in a direction in which the plurality of vacuum chambers are connected; and a mover that connects the X-ray source and the detector, but has one side connected to the moving gantry and moves along the longitudinal direction of the moving gantry.

The internal monitoring unit may further include a position detection unit for detecting the position of the mover.

The internal monitoring unit may further include a controller for controlling the movement operation of the mover based on the detection signal of the position detection unit.

The controller may control operations of the X-ray source and the detector to monitor the plurality of vacuum chambers in real time while the mover moves at a predetermined time interval.

The vacuum chamber may include an upper chamber; and a lower chamber disposed under the upper chamber and coupled to the upper chamber while moving up/down.

The crucible may be a graphite crucible, and an induction heater for induction heating the graphite crucible may be provided on an outer wall of the graphite crucible.

Heater lines constituting the induction heating heater may be arranged on the same line.

According to the present invention, since internal monitoring is possible, it is possible to effectively check the shape of the silicon carbide single crystal growth in the middle of the process without releasing the vacuum in the vacuum chamber or opening the crucible. loss) can be significantly reduced.

1 is a perspective view of a silicon carbide single crystal growth apparatus having an internal monitoring function according to an embodiment of the present invention.
FIG. 2 is an interior projection plan view of FIG. 1 ;
Fig. 3 is an interior projection front view of Fig. 1;
4 is a view for explaining the arrangement of the induction heating heater.
5 is a layout view of the X-ray source, the induction heating heater and the detector.
6 is a perspective view of an induction heating heater.
7 is a control block diagram of a silicon carbide single crystal growth apparatus having an internal monitoring function according to an embodiment of the present invention.

In order to fully understand the present invention, the operational advantages of the present invention, and the objects achieved by the practice of the present invention, reference should be made to the accompanying drawings illustrating preferred embodiments of the present invention and the contents described in the accompanying drawings.

Hereinafter, the present invention will be described in detail by describing preferred embodiments of the present invention with reference to the accompanying drawings. Like reference numerals in each figure indicate like elements.

1 is a perspective view of a silicon carbide single crystal growing apparatus having an internal monitoring function according to an embodiment of the present invention, FIG. 2 is an internal projection plan view of FIG. 1 , FIG. 3 is an internal projection front view of FIG. 1 , FIG. 4 is It is a view for explaining the arrangement of the induction heating heater, FIG. 5 is a layout view of the X-ray source, the induction heating heater and the detector, FIG. 6 is a perspective view of the induction heating heater, and FIG. 7 is an internal monitoring according to an embodiment of the present invention It is a control block diagram of a silicon carbide single crystal growth apparatus having a function.

Referring to these drawings, since it is possible to monitor the inside of the silicon carbide single crystal growth apparatus according to the present embodiment, the shape of the silicon carbide single crystal growth is effectively checked in the middle of the process even if the vacuum of the vacuum chamber 100 is released or the crucible is not opened. ), which can significantly reduce the occurrence of personal, human, and material losses.

A vacuum chamber 100 that forms a place where a silicon carbide single crystal growth process that can provide such an effect is performed, and the vacuum chamber 100 from the outside of the vacuum chamber 100 are coupled to the vacuum chamber 100, and a silicon carbide single crystal is grown It may include an internal monitoring unit 200 for monitoring (monitoring).

The vacuum chamber 100 provides a place for silicon carbide single crystals to grow. To this end, a crucible 110 in which a deposition material for silicon carbide single crystal growth is filled is disposed in the vacuum chamber 100 .

Although not necessarily, in the present embodiment, the crucible 110 may be a graphite crucible 110 (Graphite Crucible). The graphite crucible 110 is less affected by impurities, and can guarantee strong durability without cracking even at a high temperature.

In this embodiment, the silicon carbide single crystal may be grown by physical vapor deposition (PVT). That is, a silicon carbide single crystal may be grown to finally form an ingot through a method in which the material in the graphite crucible 110 is evaporated, that is, the deposition material is evaporated.

After the ingot is completely grown, the ingot can be sliced to make a silicon carbide wafer.

In order to evaporate the deposition material in the graphite crucible 110 , an induction heater 140 is coupled to the graphite crucible 110 .

The deposition material in the graphite crucible 110 may be evaporated by the action of the induction heating heater 140 to grow into a silicon carbide single crystal.

In this embodiment, the heater lines 140a constituting the induction heating heater 140 are arranged on the same line rather than a spiral. By doing so, the effect of internal monitoring can be doubled by eliminating cases where X-rays cannot penetrate. This will be described later.

Although not shown in detail, the graphite crucible 110 is provided in the vacuum chamber 100 in which the inside is formed in a vacuum during the process.

The vacuum chamber 100 includes an upper chamber 120 and a lower chamber 130 . In the present embodiment, a structure is provided in which the lower chamber 130 is coupled to the upper chamber 120 while moving up/down (dup/down).

In the present embodiment, the vacuum chamber 100 is applied as a plurality of vacuum chambers 100 that are continuously connected to each other. Considering that it takes a long time to manufacture the ingot, by applying the plurality of vacuum chambers 100 as described above, productivity can be increased.

Meanwhile, the internal monitoring unit 200 is applied to the plurality of vacuum chambers 100 . That is, the internal monitoring unit 200 is coupled to the vacuum chamber 100 from the outside of the plurality of vacuum chambers 100, and serves to monitor the shape of the silicon carbide single crystal growth. The shape in which the single crystal grows may include all sizes and sizes.

Of course, in addition to this, it is also possible to check the state of the graphite crucible 110 through the internal monitoring unit (200). That is, when silicon carbide single crystal growth is performed more than a certain number of times or after a certain period of time, cracks may occur on the surface of the graphite crucible 110 .

When cracks occur, problems such as a decrease in the purity of the produced single crystal and the occurrence of defects may occur. However, if the internal monitoring unit 200 of this embodiment is applied, there is an advantage in that the state of the graphite crucible 110 can be checked without releasing the vacuum of the vacuum chamber 100 .

In this embodiment, the internal monitoring unit 200 is commonly applied to a plurality of vacuum chambers 100 and is applied as a common internal monitoring unit 200 for internal monitoring of all of the plurality of vacuum chambers 100 .

As such, even if only one common internal monitoring unit 200 is installed, it can be applied to a plurality of vacuum chambers 100 in common, thereby reducing waste factors in facility management and maintenance.

In particular, since the common internal monitoring unit 200 applied to this embodiment performs internal monitoring by the action of X-rays, even though it has a simple structure, it has an excellent effect in monitoring the shape of the silicon carbide single crystal growth. can provide

The common internal monitoring unit 200 is disposed in one area of the vacuum chamber 100, and an X-ray source 210 (X-ray Source) that transmits X-rays into the vacuum chamber 100 at the corresponding position, and the vacuum chamber ( It is disposed on the opposite side of the X-ray source 210 with the 100) interposed therebetween, and may include a detector 220 (detector) that receives and senses X-rays transmitted from the X-ray source 210 .

For a plurality of vacuum chambers 100, the X-ray source 210 and the detector 220 are further provided with a unit moving unit 230 in the common internal monitoring unit 200 to be applied in common.

The unit moving unit 230 is connected to the X-ray source 210 and the detector 220 , and serves to move the X-ray source 210 and the detector 220 to the plurality of vacuum chambers 100 .

The pair of X-ray sources 210 and the detector 220 may interact with the plurality of vacuum chambers 100 while moving through the unit moving unit 230 .

The unit moving unit 230 includes a moving gantry 231 disposed above the plurality of vacuum chambers 100 along a direction in which the plurality of vacuum chambers 100 are connected, an X-ray source 210 and a detector 220 . ), but one side is connected to the moving gantry 231 and may include a mover (232, mover) that moves along the longitudinal direction of the moving gantry 231.

As such, in the present embodiment, by monitoring the internal situation using X-rays, the shape of the single crystal growth can be observed at regular time intervals to change or respond to process conditions.

In particular, since the X-ray source 210 and the detector 220 are commonly applied to a plurality of vacuum chambers 100 while moving, it is possible to lower the production cost of the ingot to be produced by lowering the equipment cost.

Be a little more specific about this. As a method of understanding the situation in the crucible 110 , it may be considered to measure the upper and lower temperatures of the crucible 110 , and then monitor based on the data values thereof. However, it is not possible to know the shape in which the single crystal grows in the middle of the process only by this method.

On the other hand, since X-rays have excellent ability to penetrate materials and can be expressed in images, the monitoring effect is very good when such an X-ray method is applied. That is, by arranging the X-ray source 210 and the detector 220 on both sides of the crucible 110 with the crucible 110 therebetween, the single crystal growth form is checked (monitoring) in the middle of the process using the image transmitted through the X-ray, thereby reducing human and time , can reduce material loss.

On the other hand, in applying the induction heating heater 140 for heating the graphite crucible 110 to the graphite crucible 110 as described above, in other words, the method of wiring the induction heating heater 40 to the graphite crucible 110 As shown in FIG. 4 , it may be considered to apply the heater line 40a of a zigzag method or a spiral method.

However, if the induction heating heater 40 is disposed in the same manner as in FIG. 4 , the X-ray oscillated from the X-ray source 210 may not be received by the detector 220 because it collides with the heater line 40a. The effectiveness can be significantly reduced.

Accordingly, in the present embodiment, the heater lines 140a constituting the induction heating heater 140 are arranged on the same line as in FIGS. 6 and 7 .

As such, when the heater lines 140a constituting the induction heating heater 140 are arranged on the same line, the X-ray oscillated from the X-ray source 210 is transmitted to the heater line 140a as shown by the dotted arrow in FIG. 5 . Since it does not collide, there is no problem at all in monitoring the single crystal growth form.

This will be explained in more detail. Since the X-ray uses an energy region that can inspect the shape of the crucible 110, the growth shape of the silicon carbide single crystal, the shape remaining during the evaporation of the silicon carbide powder, etc. Since the penetration area of the heater line 40a is limited, it interferes with the inspection.

In addition, since the X-ray source 210 and the detector 220 must act as a pair, if the induction heating heater 40 forms a spiral as shown in FIG. 4, both the front and the rear of the induction heating heater 40 interfere, so it is difficult to inspect .

However, when the heater lines 140a constituting the induction heating heater 140 are arranged on the same line as in the present embodiment, the X-rays oscillated from the X-ray source 210 interfere as shown by the dotted line in FIG. 5 . Since it reaches the detector 220 without it, it is possible to accurately inspect the shape of the crucible 110 as well as the growth shape of the silicon carbide single crystal, the shape remaining during the evaporation of the silicon carbide powder, and the like.

On the other hand, in the present embodiment, the common internal monitoring unit 200 of the silicon carbide single crystal growth apparatus is further equipped with a position sensing unit 240 and a controller 250 .

The position detection unit 240 is a kind of sensor that detects the position of the mover 232 . In addition, the controller 250 serves to control the movement operation of the mover 232 based on the detection signal of the position detection unit 240 .

In particular, in this embodiment, the controller 250 controls the operation of the X-ray source 210 and the detector 220 to monitor the plurality of vacuum chambers 100 in real time while the mover 232 moves at a predetermined time interval. can In this way, if the internal situation is monitored in real time and reflected in the process, it is advantageous to produce high-quality ingots.

The controller 250 performing this role may include a central processing unit 251 (CPU), a memory 252 (MEMORY), and a support circuit (253, SUPPORT CIRCUIT).

The central processing unit 251 may be one of various computer processors that can be industrially applied to control the movement operation of the mover 232 based on the detection signal of the position detection unit 240 in the present embodiment.

The memory 252 , MEMORY is connected to the central processing unit 251 . The memory 252 may be installed locally or remotely as a computer-readable recording medium, and may be easily available such as, for example, random access memory (RAM), ROM, floppy disk, hard disk, or any digital storage form. It may be at least one memory.

The support circuit 253 (SUPPORT CIRCUIT) is coupled with the central processing unit 251 to support typical operations of the processor. The support circuit 253 may include a cache, a power supply, a clock circuit, an input/output circuit, a subsystem, and the like.

In the present embodiment, the controller 250 controls the movement operation of the mover 232 based on the detection signal of the position detection unit 240 , and such a series of control processes may be stored in the memory 252 . Typically, software routines may be stored in memory 252 . Software routines may also be stored or executed by other central processing units (not shown).

Although the process according to the present invention has been described as being executed by a software routine, it is also possible that at least some of the processes of the present invention are performed by hardware.

As such, the processes of the present invention may be implemented in software executed on a computer system, implemented in hardware such as an integrated circuit, or implemented by a combination of software and hardware.

According to this embodiment, which operates in the structure as described above, since the internal monitoring of the vacuum chamber 100 is possible through the internal monitoring unit 200, silicon carbide even without releasing the vacuum of the vacuum chamber 100 or opening the crucible The shape in which the single crystal grows can be effectively checked in the middle of the process, thereby remarkably reducing the occurrence of personal, human, and material losses.

As such, the present invention is not limited to the described embodiments, and it is apparent to those skilled in the art that various modifications and variations can be made without departing from the spirit and scope of the present invention. Accordingly, it should be said that such modifications or variations fall within the scope of the claims of the present invention.

100: vacuum chamber 110: crucible
120: upper chamber 130: lower chamber
140: induction heating heater 200: internal monitoring unit
210: X-ray source 220: detector
230: unit moving unit 231: moving gantry
232: mover 240: position sensing unit
250: controller

Claims (13)

A crucible filled with a deposition material for silicon carbide single crystal growth is disposed inside, and as the deposition material from the crucible is deposited, a silicon carbide single crystal growth process is performed to form a place where adjacent ones are continuously connected a plurality of vacuum chambers; and
An internal monitoring unit coupled to the vacuum chamber from the outside of the vacuum chamber and monitoring a shape in which the silicon carbide single crystal grows,
The internal monitoring unit is a common internal monitoring unit that is commonly applied to a plurality of the vacuum chambers and performs internal monitoring for all of the plurality of the vacuum chambers, but the common internal monitoring unit is internal by the action of X-rays monitoring is carried out,
The common internal monitoring unit,
an X-ray source disposed in one region of the vacuum chamber and transmitting X-rays into the vacuum chamber at the corresponding position;
a detector disposed on the opposite side of the X-ray source with the vacuum chamber interposed therebetween and sensing X-rays transmitted from the X-ray source; and
A silicon carbide single crystal growing apparatus having an internal monitoring function, which is connected to the X-ray source and the detector, and comprises a unit moving unit for moving the X-ray source and the detector to the plurality of vacuum chambers. delete delete delete delete delete According to claim 1,
The unit moving unit,
a moving gantry disposed above the plurality of vacuum chambers in a direction in which the plurality of vacuum chambers are connected; and
A silicon carbide single crystal growing apparatus having an internal monitoring function, which connects the X-ray source and the detector, but one side is connected to the moving gantry and moves along the longitudinal direction of the moving gantry. 8. The method of claim 7,
The internal monitoring unit,
Silicon carbide single crystal growth apparatus having an internal monitoring function, characterized in that it further comprises a position sensing unit for detecting the position of the mover. 9. The method of claim 8,
The internal monitoring unit,
Silicon carbide single crystal growth apparatus having an internal monitoring function, characterized in that it further comprises a controller for controlling the movement operation of the mover based on the detection signal of the position detection unit. 10. The method of claim 9,
The controller is a silicon carbide single crystal growth apparatus having an internal monitoring function, characterized in that for controlling the operation of the X-ray source and the detector so as to monitor the plurality of vacuum chambers in real time while the mover moves at a predetermined time interval. According to claim 1,
The vacuum chamber,
upper chamber; and
A silicon carbide single crystal growth apparatus having an internal monitoring function, which is disposed under the upper chamber and includes a lower chamber coupled to the upper chamber while moving up/down. According to claim 1,
The crucible is a graphite crucible (Graphite Crucible),
A silicon carbide single crystal growth apparatus having an internal monitoring function, characterized in that an induction heater (Induction Heater) for induction heating the graphite crucible is provided on the outer wall of the graphite crucible. 13. The method of claim 12,
A silicon carbide single crystal growth apparatus having an internal monitoring function, characterized in that the heater lines constituting the induction heating heater are arranged on the same line.

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