TW202328510A - Single crystal furnace and secondary charging method which can flexibly adjust the height of the feeding tube during the charging process of the feeding tube - Google Patents

Abstract

The present invention provides a single crystal furnace and a secondary charging method. The single crystal furnace includes: a furnace body including a furnace chamber; and at least one stopper mechanism. Each of the stopper mechanisms includes a stopper and a lifting unit, wherein the stopper is arranged on the inner peripheral wall of the furnace chamber, and the stopper is connected to the lifting unit and can be driven by the lifting unit to move axially along the furnace chamber.

Description

A kind of single crystal furnace and secondary feeding method

The invention belongs to the technical field of crystal pulling, in particular to a single crystal furnace and a secondary feeding method.

Single crystal furnace is a professional equipment for producing single crystal silicon rods. In the traditional production process, the polysilicon raw material is put into a quartz crucible once and melted for production. The effective quality of single crystal silicon ingots is limited by the maximum feeding amount, which is determined by the size of the quartz crucible, and the weight of the bulk silicon material filled in the quartz crucible is the maximum feeding amount. During the melting process of the silicon material, the bulk solid silicon becomes liquid, and the space occupied by the gaps between the material blocks is released. The one-time feeding cannot achieve a sufficient amount of feeding, which reduces the maximum feeding amount to a certain extent, and the utilization rate of the crucible is not high. . Therefore, the secondary charging technology is widely used, which can improve the utilization rate of the crucible and reduce the cost.

In the related art, a typical secondary feeding system through a feeding pipe is widely used. The feeding tube is mainly composed of a guide device, a tube body, a central molybdenum rod and a conical base; the top of the central molybdenum rod can be connected to the lifting head of the single crystal furnace, the bottom is connected to the conical base through screws, and the central molybdenum rod passes through the tube body and The guide device, the bottom of the tube body and the conical base are closed to form a space for storing silicon materials. The feeding tube needs to be positioned and limited by the stopper at the corresponding position in the single crystal furnace, and then the lifting head is lowered, the tapered base and the tube body are gradually separated, and the silicon material falls to realize feeding.

However, the conventional feeding method has certain limitations: the stopper used to position and limit the feeding tube cannot be moved. As the feeding progresses, the silicon liquid level will rise and get closer to the feeding tube, causing splashing The high temperature will damage the feeding pipe, so the feeding amount can only be reduced; if the feeding amount needs to be increased, the height of the stopper should be increased, so that it is inevitable that the solution splash will be more serious at the initial stage of feeding, and the heater and heat will be damaged. The risk of the field will also reduce the service life of the guide tube.

In some technologies, a telescopic quartz feeding device is designed, which can realize the movement of the feeding pipe, but this solution needs to redesign the feeding pipe, the structure of the feeding pipe is more complicated, the cost of replacement and maintenance is higher, and the radial dimension of the overall structure is too large , it is not easy to implement in the slender furnace chamber, and it cannot be adjusted in real time. It is necessary to take out the feeding pipe to adjust, and there are certain limitations.

Embodiments of the present invention provide a single crystal furnace and a secondary charging method, which can flexibly adjust the height of the feeding tube during the charging process of the feeding tube.

The technical scheme provided by the present invention is as follows: A single crystal furnace, comprising: the furnace body, which includes the furnace chamber; and At least one set of stopper mechanisms, each set of stopper mechanisms includes a stopper and a lifting unit, the stopper is arranged on the inner peripheral wall of the furnace chamber, and the stopper is connected to the lifting unit, and driven by the lifting unit The bottom can move axially along the furnace chamber.

Exemplarily, there are at least two groups of the stopper mechanisms, and at least two groups of the stopper mechanisms are circumferentially distributed along the inner peripheral wall of the furnace chamber.

Exemplarily, a chute extending along the axial direction of the furnace chamber is provided on the inner peripheral wall of the furnace chamber, an installation cavity communicating with the chute is provided inside the side wall of the furnace chamber, and a a radial channel radially penetrating the mounting cavity and the outer peripheral wall of the furnace chamber; Wherein, the lifting unit includes a transmission element and a drive element, the stopper is arranged corresponding to the chute, the drive element is at least partly exposed to the furnace chamber, and is connected to the transmission element through the radial channel, and the transmission element is installed on the The stopper is installed in the cavity and connected to the stopper through the sliding slot, and the driving element drives the stopper to move axially along the furnace chamber through the transmission element.

Exemplarily, the transmission element includes a lead screw set, and the lead screw set includes: a lead screw disposed axially along the furnace chamber, the lead screw having first and second ends axially opposite to each other; and a slider, the slider is connected to the lead screw and can move along the lead screw as the lead screw rotates; Wherein, the driving element is directly or indirectly connected to the lead screw to drive the lead screw to rotate, and the stopper is connected to the slider to move synchronously with the slider.

Exemplarily, the driving element includes a rotating shaft and a driving member, the rotating shaft extends radially along the furnace chamber and passes through the radial channel, the rotating shaft has a third end and a fourth end opposite to each other along its axial direction, The third end is placed in the installation cavity, the fourth end extends to the outside of the outer peripheral wall of the furnace body, and the fourth end is connected to the driving member; The transmission element also includes: a bevel gear transmission group, the bevel gear transmission group connects the second end of the lead screw and the third end of the rotating shaft, and is used to convert the rotating motion of the rotating shaft around its own axis into the rotation of the lead screw rotation around its own axis.

Exemplarily, the driving member includes a handwheel or a driving motor.

Exemplarily, the bevel gear transmission group includes: a first bevel gear coaxially connected to the second end of the lead screw; a second bevel gear coaxially connected to the third end of the rotating shaft; Wherein, the bevel gears of the first bevel gear and the second bevel gear mesh with each other.

Exemplarily, the gear outer diameter of the first bevel gear is smaller than or equal to the gear outer diameter of the second bevel gear.

Exemplarily, the installation chamber includes a first chamber extending axially along the furnace chamber and a second chamber separated from the first chamber, wherein the first chamber communicates with the chute, and the wire The rod group is installed in the chute, the second end of the lead screw extends from the first chamber to the second chamber, the third end of the rotating shaft extends from the furnace chamber to the second chamber, and the cone A gear train is mounted to the second chamber.

A secondary charging method for a single crystal furnace, applied to the above single crystal furnace, the method comprises the following steps: During the secondary charging process through the feeding pipe into the single crystal furnace, the feeding pipe is positioned and limited by the stopper, and the stopper is moved along the axial direction of the furnace chamber according to predetermined rules to adjust The relative distance between the feeding pipe and the crucible in the furnace chamber in the axial direction of the furnace chamber.

The beneficial effects brought by the embodiments of the present invention are as follows: In the above scheme, the stopper used for positioning and limiting the feeding tube in the single crystal furnace is designed as a structure that can move freely along the furnace chamber axis. In this way, since the stopper can move freely along the furnace chamber axis, Therefore, the distance between the feeding pipe and the liquid surface of the crucible can be adjusted, so as to ensure that the feeding amount is sufficient each time, and also ensure the safety of the heater, thermal field and feeding pipe; moreover, since the distance between the feeding pipe and the liquid surface can be adjusted according to the actual situation, It can better cope with various emergencies and ensure the safety of the equipment; in addition, it only needs to improve the structure of the stopper to achieve its lifting purpose, the structure is simple, and the operation is convenient; in addition, when pulling multiple ingots, the height of the stopper can be directly adjusted , Pulling single and multiple free switching, not restricted by other external factors. Based on the above, macroscopically, the output of single crystal furnace in a single cycle and the utilization rate of quartz crucible are improved, and the manufacturing cost of preparing single crystal is reduced.

In order for Ligui examiners to understand the technical characteristics, content and advantages of the present invention and the effects it can achieve, the present invention is hereby combined with the accompanying drawings and appendices, and is described in detail in the form of embodiments as follows, and the drawings used therein , the purpose of which is only for illustration and auxiliary instructions, and not necessarily the true proportion and precise configuration of the present invention after implementation, so it should not be interpreted based on the proportion and configuration relationship of the attached drawings, and limit the application of the present invention in actual implementation The scope is described first.

In the description of the embodiments of the present invention, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical" , "horizontal", "top", "bottom", "inner", "outer" and other indicated orientations or positional relationships are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description , rather than indicating or implying that the device or element referred to must have a particular orientation, be constructed and operate in a particular orientation, and thus should not be construed as limiting the invention.

In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be interpreted as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of said features. In the description of the embodiments of the present invention, "plurality" means two or more, unless otherwise specifically defined. The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention.

As shown in FIGS. 1 to 3 , the single crystal furnace provided by the embodiment of the present invention includes a furnace body 10 and at least one set of stop mechanisms 20 . The furnace body 10 includes a furnace chamber, which can be provided with a crucible, a crucible shaft, a heater, etc.; Each group of the stopper mechanism 20 includes a stopper 21 and a lifting unit 22, the stopper 21 is arranged on the inner peripheral wall of the furnace chamber, and the stopper 21 is connected to the lifting unit 22, and driven by the lifting unit 22 The bottom can move axially along the furnace chamber.

In the above scheme, the stopper 21 used for positioning and limiting the feeding tube in the single crystal furnace is designed to be a structure that can move freely along the axial direction of the furnace chamber. In this way, the stopper 21 can freely move along the axial direction of the furnace chamber. Therefore, the distance between the feeding pipe and the liquid surface of the crucible can be adjusted, so as to ensure that the feeding amount is sufficient each time, and also ensure the safety of the heater, thermal field and feeding pipe; and, because the distance between the feeding pipe and the liquid surface can be adjusted according to the actual situation Adjustment can better deal with various emergencies and ensure the safety of the equipment; in addition, it only needs to improve the structure of the stopper 21 to achieve its lifting purpose, the structure is simple, and the operation is convenient; in addition, when pulling multiple ingots, it can be directly adjusted The height of the stopper 21 is free to switch between drawing single and multiple wires, and is not limited by other external factors. Based on the above, macroscopically, the output of single crystal furnace in a single cycle and the utilization rate of quartz crucible are improved, and the manufacturing cost of preparing single crystal is reduced.

As an exemplary embodiment, as shown in FIG. 1 and FIG. 2 , there may be at least two groups of the stop mechanism 20 , and at least two groups of the stop mechanism 20 are distributed along the inner peripheral wall of the furnace chamber. In a more specific embodiment, as shown in Fig. 1 and Fig. 2, there may be two groups of the stop mechanism 20, and the two groups of the stop mechanism 20 are symmetrically arranged on two radially opposite side walls of the furnace chamber. Of course, it can be understood that the specific number of the stop mechanism 20 is not limited, and there may be two or more groups.

As some exemplary embodiments, as shown in Figure 3, a chute 11 extending along the axial direction of the furnace chamber is provided on the inner peripheral wall of the furnace chamber, and a chute 11 communicating with the chute 11 is provided inside the side wall of the furnace chamber. The installation chamber 12, the side wall of the furnace chamber is also provided with a radial channel 13 radially through the installation chamber 12 and the outer peripheral wall of the furnace chamber; wherein, the lifting unit 22 includes a transmission element 221 and a drive element 222, the stop The block 21 is arranged corresponding to the chute 11, the driving element 222 is at least partly exposed to the furnace chamber, and is connected to the transmission element 221 through the radial channel 13, and the transmission element 221 is installed in the installation cavity 12, and through the The chute 11 is connected to the block 21 , and the driving element 222 drives the block 21 to move axially along the furnace chamber through the transmission element 221 .

In the above solution, the transmission element 221 is used as a power transmission component between the driving element 222 and the block 21 , and it is responsible for driving the block 21 up and down when driven by the power of the driving element 222 . The driving element 222 is at least partly exposed to the oven chamber, so that the operator can control its operation to change the position of the stopper 21 at any time.

Exemplarily, as shown in FIG. 3 , the transmission element 221 includes a lead screw set, and the lead screw set includes: A lead screw 2211 arranged axially along the furnace chamber, the lead screw 2211 has a first end and a second end opposite to its own axial direction; and A slider 2212, the slider 2212 is connected to the lead screw 2211, and can move along the lead screw 2211 as the lead screw 2211 rotates; Wherein, the driving element 222 is directly or indirectly connected to the lead screw 2211 to drive the lead screw 2211 to rotate, and the stopper 21 is connected to the slider 2212 to move synchronously with the slider 2212 .

In the above-mentioned solution, the transmission element 221 adopts the lead screw 2211 group, and the movement of the slider 2212 on the lead screw 2211 drives the movement of the stopper 21. In this way, the structure is simple, and the movement accuracy of the stopper 21 is higher.

What needs to be explained here is that the lead screw 2211 screw drives the movement of the slider 2212 , and the threaded rubber of the lead screw 2211 needs to meet the self-locking condition, so that the slider 2212 can be locked to a desired position.

Of course, it can be understood that the transmission element 221 is not limited to the lead screw 2211 group, but can also be any other structure that can drive the stopper 21 up and down.

In addition, for example, as shown in FIG. 3 , the lead screw assembly further includes a guide rod 2213 , and the slider 2212 can move along the guide rod 2213 to improve the stability of the movement of the block.

In addition, for example, as shown in FIG. 3 , the driving element 222 includes a rotating shaft 2221 and a driving member 2222 , the rotating shaft 2221 extends radially along the furnace chamber and passes through the radial channel 13 , the rotating shaft 2221 and the Bearings are arranged between the radial passages 13, so that the rotating shaft 2221 can rotate freely in the radial passage 13, and the gap between the rotating shaft 2221 and the radial passage 13 is sealed by a bearing cover; the rotating shaft 2221 has a The third end and the fourth end are axially opposite to each other, the third end is placed in the installation cavity 12, the fourth end extends to the outside of the outer peripheral wall of the furnace body 10, and the fourth end is connected to the driving member 2222; The transmission element 221 also includes: a bevel gear transmission group, the bevel gear transmission group connects the second end of the lead screw 2211 and the third end of the rotating shaft 2221, and is used to convert the rotating motion of the rotating shaft 2221 around its own axis is the rotation movement of the lead screw 2211 around its own axis.

In the above solution, the driving member 2222 can drive the rotating shaft 2221 to rotate, the rotating shaft 2221 is axially arranged to extend radially along the furnace chamber, and the lead screw 2211 axially extends along the axial direction of the furnace chamber, so the transmission element 221 A bevel gear transmission group that can transmit vertical rotation motion is also used to change the radial rotation of the shaft 2221 into the axial rotation of the screw 2211, and then convert the rotation of the screw 2211 into the axial straight line of the stopper 21. Movement, the bevel gear transmission group can also bear part of the axial force at the same time, and the speed at which the block 21 moves can be controlled by changing the transmission ratio of the bevel gear transmission group.

Exemplarily, the driving part 2222 can be selected as a handwheel to realize manual operation; the driving part 2222 can also be selected as a driving motor to realize automatic operation.

In addition, as an exemplary embodiment, as shown in FIG. 3, the bevel gear transmission group includes: The first bevel gear 223, the first bevel gear 223 is coaxially connected to the second end of the lead screw 2211; The second bevel gear 224, the second bevel gear 224 is coaxially connected to the third end of the rotating shaft 2221; Wherein, the bevel gears of the first bevel gear 223 and the second bevel gear 224 mesh with each other.

Exemplarily, the gear outer diameter of the first bevel gear 223 is smaller than or equal to the gear outer diameter of the second bevel gear 224 . With such a solution, the larger torque of the driving member 2222 can be converted into a smaller torque of the lead screw 2211 , so as to achieve the purpose of adjusting the height of the stopper 21 more precisely.

In addition, exemplary, the installation chamber 12 includes a first chamber 121 extending axially along the furnace chamber and a second chamber 122 separated from the first chamber 121, wherein the first chamber 121 and The chute 11 communicates, the lead screw 2211 is installed in the chute 11, the second end of the lead screw 2211 extends from the first chamber 121 to the second chamber 122, and the third end of the rotating shaft 2221 Extending from the furnace chamber to the second chamber 122 , the bevel gear transmission set is mounted to the second chamber 122 . With the above solution, the second chamber 122 can provide a relatively clean space for the bevel gear transmission group, so as to avoid contamination by impurities such as particles and improve its service life.

In addition, the embodiment of the present invention also provides a secondary charging method for the single crystal furnace, which is applied to the single crystal furnace in the embodiment of the present invention, and the method includes the following steps: During the secondary feeding process into the single crystal furnace through the feeding tube, the feeding tube is positioned and limited by the stopper 21, and the stopper 21 is moved along the axial direction of the furnace chamber according to predetermined rules, To adjust the relative distance between the feeding pipe and the crucible in the furnace chamber in the axial direction of the furnace chamber.

The above are only preferred embodiments of the present invention, and are not used to limit the implementation scope of the present invention. If the present invention is modified or equivalently replaced without departing from the spirit and scope of the present invention, it shall be covered by the protection of the patent scope of the present invention. in the range.

10: furnace body 11: Chute 12: Installation cavity 13: radial channel 20: Block mechanism 21: Block 22: Lifting unit 121: First Chamber 122: second chamber 221: transmission element 222: drive element 223: First bevel gear 224: second bevel gear 2211: lead screw 2212: slider 2213: guide rod 2221: Shaft 2222: Driver

Fig. 1 shows the appearance diagram of the single crystal furnace in the embodiment of the present invention; Fig. 2 represents the sectional view of the single crystal furnace in the embodiment of the present invention; Fig. 3 shows an enlarged view of the partial structure of the dotted line frame A in Fig. 1 .

10: furnace body

11: Chute

12: Installation cavity

13: radial channel

21: Block

121: First Chamber

122: second chamber

221: transmission element

222: drive element

223: First bevel gear

224: second bevel gear

2211: lead screw

2212: slider

2213: guide rod

2221: Shaft

2222: Driver

Claims (10)

A single crystal furnace, comprising: the furnace body, which includes the furnace chamber; and At least one set of stopper mechanisms, each set of stopper mechanisms includes a stopper and a lifting unit, the stopper is arranged on the inner peripheral wall of the furnace chamber, and the stopper is connected to the lifting unit, and driven by the lifting unit The bottom can move axially along the furnace chamber. The single crystal furnace as described in Claim 1, wherein, There are at least two groups of the stopper mechanisms, and at least two groups of the stopper mechanisms are circumferentially distributed along the inner peripheral wall of the furnace chamber. The single crystal furnace as described in Claim 1, wherein, The inner peripheral wall of the furnace chamber is provided with a chute extending axially along the furnace chamber, the inside of the side wall of the furnace chamber is also provided with an installation cavity communicating with the chute, and the side wall of the furnace chamber is also provided with a Radial passages in the outer peripheral wall of the installation cavity and the furnace chamber; Wherein, the lifting unit includes a transmission element and a drive element, the stopper is arranged corresponding to the chute, the drive element is at least partly exposed to the furnace chamber, and is connected to the transmission element through the radial channel, and the transmission element is installed on the The stopper is installed in the cavity and connected to the stopper through the sliding slot, and the driving element drives the stopper to move axially along the furnace chamber through the transmission element. The single crystal furnace as described in claim 3, wherein, The transmission element includes a lead screw set including: a lead screw disposed axially along the furnace chamber, the lead screw having first and second ends axially opposite to each other; and a slider, the slider is connected to the lead screw and can move along the lead screw as the lead screw rotates; Wherein, the driving element is directly or indirectly connected to the lead screw to drive the lead screw to rotate, and the stopper is connected to the slider to move synchronously with the slider. The single crystal furnace as described in claim 4, wherein, The driving element includes a rotating shaft and a driving member. The rotating shaft extends radially along the furnace chamber and passes through the radial channel. The rotating shaft has a third end and a fourth end opposite to its own axial direction. The third end Placed in the installation cavity, the fourth end extends to the outside of the outer peripheral wall of the furnace body, and the fourth end is connected to the driving member; The transmission element also includes: a bevel gear transmission group, the bevel gear transmission group connects the second end of the lead screw and the third end of the rotating shaft, and is used to convert the rotating motion of the rotating shaft around its own axis into the rotation of the lead screw rotation around its own axis. The single crystal furnace as described in claim 5, wherein, The drive includes a handwheel or a drive motor. The single crystal furnace as described in claim 5, wherein, The bevel gear transmission group includes: a first bevel gear coaxially connected to the second end of the lead screw; a second bevel gear coaxially connected to the third end of the rotating shaft; Wherein, the bevel gears of the first bevel gear and the second bevel gear mesh with each other. The single crystal furnace as described in Claim 7, wherein, The gear outer diameter of the first bevel gear is smaller than or equal to the gear outer diameter of the second bevel gear. The single crystal furnace as described in claim 5, wherein, The installation chamber includes a first chamber extending axially along the furnace chamber and a second chamber separated from the first chamber, wherein the first chamber communicates with the chute, and the lead screw group is mounted on In the chute, the second end of the lead screw extends from the first chamber to the second chamber, the third end of the rotating shaft extends from the furnace chamber to the second chamber, and the bevel gear transmission set is installed to the second chamber. A secondary charging method for a single crystal furnace, applied to the single crystal furnace as described in any one of claims 1 to 8, the method includes the following steps: During the secondary charging process through the feeding pipe into the single crystal furnace, the feeding pipe is positioned and limited by the stopper, and the stopper is moved along the axial direction of the furnace chamber according to predetermined rules to adjust The relative distance between the feeding pipe and the crucible liquid level in the furnace chamber in the axial direction of the furnace chamber.

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