TWI732376B - Growth apparatus for continuous czochralski - Google Patents

Abstract

A growth apparatus for Continuous Czochralski includes a crucible, a feeding module, a rotating shaft, a thermal-insulating module, and a heating module, wherein the rotating shaft has an axis and drives the crucible to rotate around the axis. The thermal-insulating module includes a first thermal-insulating layer and a second thermal-insulating layer, wherein the first thermal-insulating layer has a first thickness in an axial direction of the axis, and the second thermal-insulating layer has a second thickness in the axial direction of the axis. The crucible is disposed between the first thermal-insulating layer and the second thermal-insulating layer. The first thermal-insulating layer and the second thermal-insulating layer are spaced apart by a minimum distance in the axial direction. A ratio of the minimum distance to the first thickness is between 1:0.2 and 1:0.35, and a ratio of the minimum distance to the second thickness is between 1:0.6 and 1:0.75. The heating module is disposed between the crucible and the thermal-insulating module.

Description

Continuous Czochralski single crystal growth equipment

The present invention is related to crystal pulling equipment; in particular, it refers to a crystal pulling equipment suitable for Continuous Czocharlski (CCz).

It is known that in a typical CZ (Czochralski) process, a silicon material is placed in a crucible, and the silicon material is melted into liquid silicon at a temperature of about 1416°C, and then a silicon seed crystal with a predetermined crystal orientation is lowered to contact On the surface of the liquid silicon, under proper temperature control, the liquid silicon forms a single crystal on the silicon seed crystal with a predetermined crystalline orientation with the silicon seed crystal, and then rotates and slowly pulls the silicon seed crystal and the crucible to A silicon crystal rod is formed under the silicon seed crystal.

Under the traditional CZ method, a crucible can only be used once, and only one ingot can be produced at a time. In order to improve the aforementioned problems, the industry has begun to use the Continuous Czocharlski (CCz) method to produce ingots. During the single crystal drawing process, the silicon material is continuously or periodically replenished in the crucible, so that the drawing of several crystal rods can be completed within the life cycle allowed by a single crucible.

In the above-mentioned single crystal silicon manufacturing process, a heater must be used to provide the temperature required to melt the silicon material. When the heat is dissipated from the continuous Czochralski single crystal growth equipment to the outside, in order to maintain a sufficient high temperature, it is necessary to increase the temperature. The power of the heater causes a large amount of waste of heat energy. Therefore, how to improve the heat dissipation from the continuous Czochralski single crystal growth equipment to the outside is an urgent problem to be solved.

In view of this, the object of the present invention is to provide a continuous Czochralski single crystal growth equipment with a thermal insulation module to improve the problem of heat escaping from the continuous Czochralski single crystal growth equipment to the outside.

In order to achieve the above objective, the present invention provides a continuous Czochralski single crystal growth equipment including a crucible, a feeding module, a rotating shaft, a heat insulation module and a heating module, the crucible has a partition wall, The dividing wall divides the internal accommodating space of the crucible into a feeding area and a growth area, the dividing wall has at least one through hole communicating the feeding area and the growth area; the feeding module is used to provide solid raw materials to The feeding area; the rotating shaft has an axis, and the rotating shaft drives the crucible to rotate about the axis; the thermal insulation module includes a first thermal insulation layer and a second thermal insulation layer, the first partition The thermal layer has a first thickness in the axial direction, the second thermal insulation layer has a second thickness in the axial direction, and the crucible is disposed between the first thermal insulation layer and the second thermal insulation layer, There is a minimum distance between the first heat insulation layer and the second heat insulation layer in the axial direction, and the ratio of the distance between the minimum distance and the first thickness is between 1:0.2 and 0.35, and the minimum distance is between 1:0.2 and 0.35. The thickness distance ratio is between 1:0.6 and 1:0.75; the heating module is arranged between the crucible and the heat insulation module.

The effect of the present invention is that the heating module is arranged between the crucible and the heat insulation module, and through the arrangement of the first heat insulation layer, the second heat insulation layer and the third heat insulation layer, it can be effectively The thermal insulation can escape to the outside of the continuous Czochralski single crystal growth equipment, which can reduce the power of the heater, thereby achieving the effect of reducing the production cost.

〔this invention〕

1: Continuous Czochralski single crystal growth equipment

10: Cavity

20: Crucible

22: Partition wall

201: Feeding area

202: growth area

221: Through Hole

30: Feeding module

40: Rotation axis

401: Axis

50: Thermal insulation module

52: The first insulation layer

521: Feed Channel

522: open

54: second insulation layer

541: Upper insulation layer

542: Lower Insulation Layer

56: The third insulation layer

60: Heating module

62: The first heater

64: second heater

70: Hanging wire

S: solid raw material

T1: first thickness

T2: second thickness

D1: Minimum distance

D2: Maximum height

D3: Radial length

D4: Caliber

Dd: Difference

T3: third thickness

FIG. 1 is a schematic diagram of a continuous Czochralski single crystal growth device according to a preferred embodiment of the present invention.

Fig. 2 is a schematic diagram of the feeding of the continuous Czochralski single crystal growth equipment of the above preferred embodiment.

In order to explain the present invention more clearly, the preferred embodiments are described in detail in conjunction with the drawings as follows. Please refer to Figures 1 to 2, which is a preferred embodiment of the continuous Czochralski single crystal growth equipment 1 of the present invention. It includes a cavity 10, a crucible 20, a feed module 30, a rotating shaft 40, and a The heat insulation module 50 and a heating module 60, the crucible 20, the rotating shaft 40, the heat insulation module 50 and the heating module 60 are all arranged in the cavity 10.

The cavity 10 is in the shape of a barrel. The thermal insulation module 50 includes a first thermal insulation layer 52, a second thermal insulation layer 54 and a third thermal insulation layer 56, and the second thermal insulation layer 54 is filled in the At the bottom of the cavity, the first heat insulation layer 52 is disposed on the top of the cavity 10, and the third heat insulation layer 56 is disposed between the first heat insulation layer 52 and the second heat insulation layer 54, and The third heat-insulating layer 56 is arranged around the inner wall of the cavity 10, the crucible 20 is arranged between the first heat-insulating layer 52 and the second heat-insulating layer 54, and the crucible 20 is arranged on the first insulating layer. Below the thermal layer 52 and above the second heat insulation layer 54, and the outer side wall of the crucible 20 is surrounded by the third heat insulation layer 56.

The heating module 60 is arranged between the crucible 20 and the heat insulation module 50. The heating module 60 is used to provide the heat energy required for the melting of the raw material in the crucible 20 to melt the silicon raw material into a liquid. In terms of state, the temperature is about 1416°C. In this embodiment, the heating module 60 includes a first heater 62 and a second heater 64. The first heater 62 surrounds the outer side wall of the crucible 20 The first heater 62 is located between the crucible 20 and the third heat insulation layer 56, the second heater 64 is located near the bottom of the crucible 20, and the second heater 64 is located at the bottom of the crucible 20. Between the crucible 20 and the second heat insulation layer 54, That is, the first heat insulation layer 52, the second heat insulation layer 54 and the third heat insulation layer 56 together form a heat insulation shield, which can effectively prevent the heat energy provided by the heating module 60 from escaping to the cavity Body 10 outside.

In this embodiment, the crucible 20 is a quartz crucible or a graphite crucible containing a quartz lining. The crucible 20 has a partition wall 22 that divides the internal accommodating space of the crucible into a feeding area 201 and a In the growth area 202, the partition wall 22 has at least one through hole 221 that communicates with the feed area 201 and the growth area 202. The number of the at least one through hole 221 may be one or more. The first heat insulation layer 52 has a The feeding channel 521 penetrates the first heat insulation layer 52, the feeding module 30 is connected to the feeding channel 521, and the solid raw material S provided by the feeding module 30 passes through the feeding channel 521 enters the feeding area 201, whereby the solid raw material S enters the feeding area 201 through the feeding channel 521, is heated and melted by the heating module 60, and then flows to the at least one through hole 221 In the growth area 202, and the at least one through hole 221 can restrict the unmelted solid raw material S from entering the growth area. In practice, the feed module 30 can control the feed amount or feed rate, and continuously or periodically replenish the silicon solid during the single crystal drawing process of the Continuous Czocharlski (CCz) method. The raw materials are in the feeding area 201 of the crucible 20, so that several ingots can be drawn within the life cycle allowed by a single crucible.

The bottom of the crucible 20 is connected with the rotating shaft 40. The rotating shaft has an axis 401. The rotating shaft 40 can be controlled to drive the crucible 20 to rotate around the axis 401 and control the rotation speed of the crucible 20. The first insulation layer 52 has a first thickness T1 in the direction of the axis 401, the second insulation layer 54 has a second thickness T2 in the direction of the axis 401, and the crucible 20 is disposed on the first insulation Between the layer 52 and the second thermal insulation layer 54, the first thermal insulation layer 52 to the second thermal insulation layer 54 are separated by a minimum distance in the direction of the axis 401 From D1, the distance ratio between the minimum distance D1 and the first thickness T1 is between 1:0.2 and 1:0.35, and the distance ratio between the minimum distance D1 and the second thickness T2 is between 1:0.6 and 1:0.75 Preferably, the ratio of the first thickness T1 to the second thickness T2 is between 1:1.6 and 1:2.5, the crucible 20 has a maximum height D2 in the direction of the axis 401, and the maximum height D2 is The length ratio of the minimum distance D1 is between 1:1.5 and 1:2.3, whereby the first heat insulation layer 52 and the second heat insulation layer 54 can be provided on the first heat insulation layer 52 and the second heat insulation layer 52 The heating module 60 between the heat insulation layers 54 is well shielded to prevent the heat generated by the heating module 60 from escaping to the outside of the cavity 10.

The continuous Czochralski single crystal growth apparatus 1 further includes a suspension wire 70, the suspension wire 70 passes through an opening 522 of the first heat insulation layer 52, and the suspension wire 70 is connected with a seed crystal to lower the seed crystal to the growth The area 202 contains the surface of liquid silicon, and the seed crystal is slowly raised with an appropriate pull-off rate to continue the crystallization process. The first heat insulation layer 52 has a radial length D3, a diameter D4 of the opening 522 and the radial length The length ratio of D3 is between 1:1.5 and 1:2. By limiting the length ratio between the diameter D4 of the opening 522 and the radial length D3, the heat energy generated by the heating module 60 can be effectively prevented from the opening 522. Escape to the outside of the cavity 10.

In this embodiment, the first insulation layer 52 and the second insulation layer 54 are made of carbon fiber material, and the third insulation layer 56 is made of graphite material. Preferably, the third insulation layer The thermal layer 56 is a graphite blanket, which is made of graphite or carbon fiber material with thermal insulation and heat resistance, which can improve the first thermal insulation layer 52, the second thermal insulation layer 54 and the third thermal insulation layer 56. Insulation effect, it is worth mentioning that in this embodiment, the top of the third thermal insulation layer 56 is connected to the first thermal insulation layer 52, and the bottom of the third thermal insulation layer 56 is connected to the second thermal insulation layer. The layers 54 are connected, so as to improve the degree of adhesion between the first heat insulation layer 52, the second heat insulation layer 54 and the third heat insulation layer 56, so as to reduce the heat energy from the first heat insulation layer 52, the first heat insulation layer 52, the third heat insulation layer 56 The gap between the second insulation layer 54 and the third insulation layer 56 escapes. In addition, in this embodiment, the second insulation layer The thermal layer 54 includes an upper insulating layer 541 and a lower insulating layer 542. The lower insulating layer 542 is disposed at the bottom of the cavity 10, and the upper insulating layer 541 is disposed at the top center of the lower insulating layer 542 , The upper heat insulation layer 541 and the lower heat insulation layer 542 are both cylindrical, and the radial length of the upper heat insulation layer 541 is smaller than the radial length of the lower heat insulation layer 542, and the third heat insulation layer 56 has A third thickness T3 is the difference Dd between the radial length of the upper insulating layer 541 and the radial length of the lower insulating layer 542, the bottom of the third insulating layer 56 and the top of the lower insulating layer 542 Connecting and surrounding the outer periphery of the upper heat insulation layer 541, in other embodiments, the upper heat insulation layer 541 and the lower heat insulation layer 542 may also be integrally formed, and are not limited to the above.

The above are only the preferred and feasible embodiments of the present invention. Any equivalent changes made by applying the specification of the present invention and the scope of the patent application should be included in the patent scope of the present invention.

1...Continuous Czochralski single crystal growth equipment 10...cavity 20...Crucible 22...partition wall 201...feeding area 202...growth area 221...Through Hole 30...Feeding module 40...Rotation axis 401...axis 50...Insulation module 52...First insulation layer 521...Inlet channel 522...Opening 54...Second insulation layer 541...Upper insulation layer 542...Lower insulation layer 56...The third insulation layer 60...heating module 62...The first heater 64...The second heater 70...Suspended wire T1...First thickness T2...Second thickness D1...Minimum distance D2...Maximum height D3...radial length D4...caliber Dd...Difference T3...the third thickness

Claims (9)

A continuous Czochralski single crystal growth equipment, comprising: a crucible with a partition wall, the partition wall partitions the crucible internal accommodating space into a feed area and a growth area, the partition wall has at least one through hole communicating with the The feeding area and the growth area; a feeding module for supplying solid raw materials to the feeding area; a rotating shaft with an axis, and the rotating shaft drives the crucible to rotate with the axis as the axis; a heat insulation The module includes a first insulation layer and a second insulation layer, the first insulation layer has a first thickness in the axial direction, and the second insulation layer has a second insulation in the axial direction Thickness, the crucible is arranged between the first heat insulation layer and the second heat insulation layer, a minimum distance between the first heat insulation layer and the second heat insulation layer in the axial direction, the minimum distance and the The distance ratio of the first thickness is between 1:0.2 and 1:0.35, and the distance ratio between the minimum distance and the second thickness is between 1:0.6 and 1:0.75; and a heating module set between the crucible and Between the thermal insulation modules; wherein, the crucible is arranged below the first thermal insulation layer and above the second thermal insulation layer, the first thermal insulation layer and the second thermal insulation layer are made of carbon fiber material . The continuous Czochralski single crystal growth apparatus according to claim 1, comprising a suspension wire passing through an opening of the first heat insulation layer, the first heat insulation layer having a radial length, and the diameter of the opening is the same as the radial direction. The length to length ratio is between 1:1.5 and 1:2. The continuous Czochralski single crystal growth equipment according to claim 1, wherein the first heat insulation layer has a feed channel, the feed channel penetrates the first heat insulation layer, and the solid raw material provided by the feed module passes through The feed channel enters the feed zone. The continuous Czochralski single crystal growth equipment according to claim 1, wherein the ratio of the first thickness to the second thickness is between 1:1.6 and 1:2.5. The continuous Czochralski single crystal growth apparatus according to claim 1, wherein the crucible has a maximum height in the axial direction, and the ratio of the maximum height to the minimum distance is between 1:1.5 and 1:2.3. The continuous Czochralski single crystal growth equipment according to claim 1, wherein the thermal insulation module includes a third thermal insulation layer, and the third thermal insulation layer is disposed at a position surrounding the outer side wall of the crucible. The continuous Czochralski single crystal growth equipment according to claim 6, wherein the top of the third heat insulation layer is connected to the first heat insulation layer, and the bottom of the third heat insulation layer is connected to the second heat insulation layer. The continuous Czochralski single crystal growth device according to claim 6, wherein the third heat insulation layer is made of graphite material. The continuous Czochralski single crystal growth device according to claim 8, wherein the third heat insulation layer is a graphite blanket.

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