CN211036174U

CN211036174U - Crystal growth device

Info

Publication number: CN211036174U
Application number: CN201920645452.3U
Authority: CN
Inventors: 沈伟民
Original assignee: Zing Semiconductor Corp
Current assignee: Zing Semiconductor Corp
Priority date: 2019-04-30
Filing date: 2019-04-30
Publication date: 2020-07-17
Anticipated expiration: 2029-04-30

Abstract

The utility model provides a crystal growth device, include: the crucible furnace comprises a furnace body, wherein a crucible is arranged in the furnace body, and a melt is contained in the crucible; a pulling device disposed above the crucible and configured to pull the crystal during crystal growth; a melting lid secured to a lower end of the pulling device configured to reduce heat loss from the melt. According to the utility model provides a crystal growth device sets up the melting lid through the top at the crucible, has reduced the heat loss of fuse-element, has shortened the raw materials time of heating melting in the crucible, has reduced the energy consumption of heater, and then has improved production efficiency, has reduced manufacturing cost.

Description

Crystal growth device

Technical Field

The utility model relates to a crystal growth technical field particularly relates to a crystal growth device.

Background

With the rapid development of the Integrated Circuit (IC) industry, device manufacturers have placed more stringent requirements on IC-grade silicon single crystal materials, which are the substrate materials necessary for device fabrication. Czochralski (CZ) is the most important method for growing single crystals from a melt in the prior art, and is characterized in that raw materials for forming the crystal are placed in a crucible to be heated and melted, the melt is pulled by contacting a seed crystal on the surface of the melt, the seed crystal and the melt are continuously rearranged into atoms or molecules on an interface under controlled conditions, and the single crystal is grown by solidification gradually along with temperature reduction.

However, during the crystal growth, heat of the melt is transferred to the furnace body in the form of heat radiation or the like, resulting in heat loss. The time for putting the raw materials in the crucible for heating and melting is prolonged, the energy consumption of the heater is increased, the production efficiency is reduced, and the production cost is increased.

Therefore, it is necessary to provide a new crystal growth apparatus to solve the above problems.

SUMMERY OF THE UTILITY MODEL

In the summary section a series of concepts in a simplified form is introduced, which will be described in further detail in the detailed description section. The inventive content does not imply any attempt to define the essential features and essential features of the claimed solution, nor is it implied to be intended to define the scope of the claimed solution.

The utility model provides a crystal growth device, include:

the crucible furnace comprises a furnace body, wherein a crucible is arranged in the furnace body, and a melt is contained in the crucible;

a pulling device disposed above the crucible and configured to pull the crystal during crystal growth;

a melting lid secured to a lower end of the pulling device configured to reduce heat loss from the melt.

Further, the melting lid is made of a heat insulating material.

Further, the melt lid includes an outer housing portion comprising a rigid plastic material and an inner filling portion comprising a flexible porous material and/or a rigid porous material.

Further, the material of the outer shell portion comprises graphite, continuous fiber composite, or molybdenum.

Further, the inner filling part comprises graphite felt and/or graphite felt.

Further, the melt cap comprises a cylindrical shape, a spherical shape, an ellipsoidal shape, or a combination thereof.

Further, the pulling device comprises a pulling rope and/or a pulling hard rod.

Further, the diameter range of the melting lid includes 150mm to 750 mm.

Further, the diameter of the melting cover is smaller than the distance between the reflecting screens.

According to the utility model provides a crystal growth device sets up the melting lid through the top at the crucible, has reduced the heat loss of fuse-element, has shortened the raw materials time of heating melting in the crucible, has reduced the energy consumption of heater, and then has improved production efficiency, has reduced manufacturing cost.

Drawings

The following drawings of the present invention are used herein as part of the present invention for understanding the present invention. There are shown in the drawings, embodiments and descriptions of the invention, which are used to explain the principles and devices of the invention. In the drawings, there is shown in the drawings,

FIG. 1 is a schematic view of a crystal growing apparatus of the present invention;

fig. 2 is a top view of the melting lid of the present invention.

Reference numerals

1. Furnace body 2, carry and draw brilliant rope

3. Melting cover 4 and single crystal silicon rod

5. Reflecting screen 6, silicon melt

7. Crucible 8 and heater

9. Crucible lifting mechanism

Detailed Description

In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. It will be apparent, however, to one skilled in the art, that the present invention may be practiced without one or more of these specific details. In other instances, well-known features have not been described in order to avoid obscuring the present invention.

In order to provide a thorough understanding of the present invention, detailed steps will be set forth in the following description in order to explain the crystal growth apparatus of the present invention. It is apparent that the practice of the invention is not limited to the specific details known to those skilled in the art. The preferred embodiments of the present invention are described in detail below, however, other embodiments of the present invention are possible in addition to these detailed descriptions.

It will be understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

Czochralski (CZ) is the most important method for growing single crystals from a melt in the prior art, and is characterized in that raw materials for forming the crystal are placed in a crucible to be heated and melted, the melt is pulled by contacting a seed crystal on the surface of the melt, the seed crystal and the melt are continuously rearranged into atoms or molecules on an interface under controlled conditions, and the single crystal is grown by solidification gradually along with temperature reduction. However, during the crystal growth, heat of the melt is transferred to the furnace body in the form of heat radiation or the like, resulting in heat loss. The time for putting the raw materials in the crucible for heating and melting is prolonged, the energy consumption of the heater is increased, the production efficiency is reduced, and the production cost is increased.

To the above problem, the utility model provides a crystal growth device, as shown in fig. 1, include:

the furnace comprises a furnace body 1, wherein a crucible 7 is arranged in the furnace body 1, and a melt is contained in the crucible 7;

a pulling device disposed above the crucible 7 and configured to pull the crystal during crystal growth;

a melting lid 3, the melting lid 3 being fixed to a lower end of the pulling device and configured to reduce heat loss of the melt.

As shown in figure 1, the crystal growing device provided by the utility model comprises a furnace body 1, a crucible 7 is arranged in the furnace body 1, and a melt is contained in the crucible 7.

Illustratively, the furnace body 1 is a stainless steel cavity, and the furnace body 1 is vacuum or filled with protective gas. As an example, the shielding gas is argon, the purity of the shielding gas is more than 97%, the pressure is 5mbar-100mbar, and the flow rate is 70slpm-200 slpm.

Illustratively, the crucible 7 is made of a high temperature and corrosion resistant material, and the crucible 7 contains a melt for crystal growth. In one embodiment, crucible 7 comprises a quartz crucible and/or a graphite crucible, and crucible 7 contains a silicon material, such as polysilicon. The silicon material is heated in crucible 7 to form silicon melt 6 for growing single crystal silicon rod 4, and specifically, a seed crystal is immersed in silicon melt 6, rotated by a seed crystal shaft and slowly pulled, so that silicon atoms grow along the seed crystal to form single crystal silicon rod 4. The seed crystal is formed by cutting or drilling a silicon single crystal with a certain crystal orientation, the common crystal orientation is <100>, <111>, <110> and the like, and the seed crystal is generally a cylinder.

Illustratively, a heater 8 is disposed on the periphery of the crucible 7, and the heater 8 includes a graphite heater, and may be disposed on a side surface of the crucible 7, or disposed on a side surface and a bottom surface of the crucible 7, and configured to heat the crucible 7. Further, the heaters 8 may be disposed on both sides of the crucible 7, or may be disposed around the crucible 7 to make the thermal field distribution of the crucible 7 uniform. Further, the heater 8 is turned on, and the silicon material is heated to a melting temperature of 1420 ℃ or higher, so that the silicon material is completely melted into the silicon melt 6, and the melting time is about 12 hours.

Illustratively, a reflecting screen 5 is also arranged in the furnace body 1, is positioned above the crucible 7 and is positioned at the periphery of the monocrystalline silicon rod 4. Further, the material of the reflecting screen 5 includes, but is not limited to, molybdenum. The radial cross-sectional shape of the reflecting screen 5 includes, but is not limited to, circular, rectangular, hexagonal, etc.

Further, the crystal growth apparatus of the present invention further includes a crucible elevating mechanism 9 configured to support and rotate the crucible shaft to effect elevation of the crucible 7.

As shown in FIG. 1, the crystal growing apparatus provided by the present invention further comprises a pulling device disposed above the crucible 7 and configured to pull the crystal during the crystal growing process.

Illustratively, the pulling device comprises a pulling rope, a pulling hard rod or a combination thereof, and preferably, the pulling device comprises a pulling rope 2. Further, the pulling rope 2 is formed by twisting a plurality of groups of tungsten wires.

Illustratively, the fusion cover 3 may be secured to the lower end of the pulling apparatus by any suitable means, preferably, the fusion cover 3 is removably secured to the lower end of the pulling apparatus.

As shown in FIG. 1, the crystal growing apparatus provided by the present invention further comprises a melting cover 3, wherein the melting cover 3 is disposed at the lower end of the pulling apparatus and configured to reduce the heat loss of the melt.

Illustratively, the melting lid 3 is positioned above the melt and "covers" the melt to reduce the heat radiation of the melt. Therefore, the size of the melting lid 3 should be as large as possible to "cover" more melt, however, the diameter of the melting lid 3 should be smaller than the distance between the reflecting screens, as shown in fig. 1. Illustratively, the diameter range of the melting lid 3 includes 150mm to 750 mm.

Illustratively, the fused cover is made of a thermally insulating material.

As an example, the melting lid 3 is made of a hard insulating material including, but not limited to, graphite, Continuous Fiber Composite (CFC), molybdenum, or the like. Optionally, the surface of the melting lid 3 is formed with a coating.

Further, in order to achieve a better thermal insulation effect, the melting lid 3 is composed of an outer shell portion and an inner filling portion, wherein the outer shell portion comprises a hard plastic material, mainly for forming a support shell; the inner filling part comprises a flexible porous material and/or a hard porous material, and is mainly used for heat insulation.

As an example, the material of the outer housing portion includes, but is not limited to, a hard thermal insulating material such as graphite, CFC, or molybdenum. The inner filling part includes but is not limited to loose porous heat insulation materials such as graphite felt, graphite solid felt and the like. The heat preservation and insulation effect of the material of the internal filling part is superior to that of the material of the external shell part, so that a better heat insulation effect is realized.

Illustratively, the shape of the fusion lid 3 includes, but is not limited to, cylindrical, spherical, ellipsoidal, or a combination thereof. On the one hand, the shape can be filled with heat insulation material as much as possible; on the other hand, the above shape can also satisfy the requirement of direction control.

In one embodiment, before the crystal grows, for example, during the process of melting the silicon material into the silicon melt, the crystal does not grow between the melting cover 3 and the melt, the distance between the melting cover 3 and the upper surface of the crucible is shortest, the heat radiation can be effectively prevented, and the material melting time can be effectively shortened.

In another embodiment, the melting cover 3 is positioned above the melt during the crystal growth process, such as seeding, shouldering, shoulder rotating, diameter equalizing and ending, to effectively prevent heat radiation and thus reduce the energy consumption of the heater.

The present invention has been described in terms of the above embodiments, but it is to be understood that the above embodiments are for purposes of illustration and description only and are not intended to limit the invention to the described embodiments. Furthermore, it will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and that many more modifications and variations are possible in light of the teaching of the present invention and are within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. A crystal growth apparatus, comprising:

2. The crystal growth apparatus of claim 1, wherein the melt lid is made of a thermally insulating material.

3. The crystal growth apparatus of claim 2, wherein the melt lid comprises an outer housing portion and an inner fill portion, the outer housing portion comprising a hard molding material.

4. The crystal growth apparatus of claim 3, wherein the material of the outer shell portion comprises graphite, continuous fiber composite, or molybdenum.

5. The crystal growth apparatus of claim 3, wherein the inner fill portion comprises graphite felt and/or graphite felt.

6. The crystal growth apparatus of claim 1, wherein the melt lid comprises a cylindrical shape, a spherical shape, an ellipsoidal shape, or a combination thereof.

7. The crystal growth apparatus of claim 1, wherein the pulling device comprises a pulling rope and/or a pulling hard rod.

8. The crystal growth apparatus of claim 1, wherein the melting lid has a diameter in a range including 150mm to 750 mm.

9. The crystal growth apparatus of claim 8, wherein a diameter of the melt lid is less than a distance between the reflective screens.