Secondary feeding system and secondary feeding method

Abstract

The present invention relates to a secondary feeding system, which includes a single crystal furnace and a secondary feeding device. The secondary feeding device includes a feeding cylinder, a lifting rod and a quartz cone. A convex ring is provided on the outer peripheral surface of the feeding cylinder. The single crystal furnace includes a main furnace chamber and a secondary furnace chamber. A stop block matched with the convex ring is provided on the inner side wall of the secondary furnace chamber. The secondary feeding system further includes a first moving structure, which is used to control the lifting movement of the stop block. The present invention also relates to a secondary feeding method. Through the arrangement of the first moving structure, the lifting of the stop block can be realized, so as to realize the independent lifting of the feeding cylinder, increase the distance between the feeding cylinder and the quartz cone, solve the problem of material jamming, and will not cause damage to the feeding cylinder.

Description

Technical Field

[0001] The present invention relates to the technical field of secondary feeding, and particularly to a secondary feeding system and a secondary feeding method. Background Art

[0002] In the semiconductor field, during the pulling process of a silicon single crystal rod, initial charging is required, and silicon materials of different sizes are loaded into a quartz crucible. The weight of the initial charging is not sufficient to pull the length of the silicon rod required. Therefore, it is necessary to melt the initial silicon materials to reduce the space and then perform secondary feeding in order to reach the weight corresponding to the crystal rod of the required length for crystal pulling. During secondary feeding, the secondary feeding tube filled with silicon materials is integrally lifted into the secondary furnace chamber by a traction device. After the lifting is completed, the stopper is pushed out, the secondary furnace chamber is closed, and the isolation valve is opened. During secondary feeding, the whole secondary feeding tube descends. When it descends to a certain height, the stopper in the secondary furnace chamber will block the retaining ring of the feeding tube, causing the quartz cone to separate from the secondary feeding tube. Then, the silicon materials slide down from around the quartz cone into the silicon solution. A large amount of silicon materials falling into the silicon solution results in un-melted materials piling up under the quartz cone. When continuing to feed, silicon materials with slightly larger sizes are stuck between the quartz cone and the feeding tube. The quartz cone is close to the liquid surface and is blocked by the un-melted silicon materials and cannot descend. Moreover, the stopper is fixed on the secondary furnace chamber and cannot move, and the secondary feeding tube cannot rise either. In production, in order to increase production capacity and reduce the melting time, the whole secondary feeding tube is lifted by the traction device to adjust the position. During the lifting process, the retaining ring of the feeding tube separates from the stopper in the secondary furnace chamber, and the weight of the quartz tube is all pressed on the silicon materials stuck between the quartz cone and the feeding tube. The silicon materials fall off, causing the feeding tube to quickly descend and hit the stopper in the secondary furnace chamber, breaking the retaining ring of the secondary feeding tube and affecting the quality of the crystal rod. Summary of the Invention

[0003] In order to solve the above technical problems, the present invention provides a secondary feeding system and a secondary feeding method to solve the problem of material jamming during secondary feeding.

[0004] To achieve the above object, the technical solution adopted in the embodiment of the present invention is: a secondary feeding system, including a single crystal furnace and a secondary feeding device. The secondary feeding device includes a feeding cylinder, a lifting rod, and a quartz cone. A convex ring is provided on the outer peripheral surface of the feeding cylinder. The single crystal furnace includes a main furnace chamber and a secondary furnace chamber. A stopper matched with the convex ring is provided on the inner side wall of the secondary furnace chamber.

[0005] The secondary feeding system further includes a first moving structure for controlling the lifting movement of the stopper.

[0006] Optionally, the first moving structure includes a lead screw, and the stopper is spirally arranged on the lead screw.

[0007] Optionally, a track is provided on the inner side wall of the secondary furnace chamber, and the stopper is movably arranged on the track.

[0008] Optionally, a clamping groove serving as the track is provided on the inner side wall of the auxiliary furnace chamber. The extending direction of the clamping groove is parallel to the axial direction of the single crystal furnace. A protrusion is provided on the side surface of the stopper for connecting to the inner side wall, and the protrusion is slidably connected in the clamping groove.

[0009] Optionally, a second moving structure is further included, which is used to control the lifting movement of the charging cylinder.

[0010] Optionally, the second moving structure includes a driving part and a transmission connecting part, and the transmission connecting part is connected between the driving part and the charging cylinder.

[0011] Optionally, the transmission connecting part includes at least two oppositely arranged transmission connecting rods. The transmission connecting rods are connected to the outer peripheral surface of the charging cylinder, and the transmission connecting rods are connected to the side of the convex ring away from the quartz cone.

[0012] Optionally, the transmission connecting part includes at least two oppositely arranged transmission connecting rods, and the transmission connecting rods are connected to the side surface of the convex ring away from the quartz cone.

[0013] An embodiment of the present invention further provides a secondary charging method, which uses the above-mentioned secondary charging system for secondary charging, and includes the following steps:

[0014] Control the charging cylinder loaded with silicon material to enter the single crystal furnace until the convex ring on the charging cylinder contacts the stopper in the auxiliary furnace chamber;

[0015] Control the separation of the quartz cone from the charging cylinder so that the silicon material falls;

[0016] When the falling silicon material is stuck between the charging cylinder and the quartz cone and cannot be charged continuously, control the stopper to rise through the first moving structure to drive the charging cylinder to rise, so as to increase the distance between the quartz cone and the charging cylinder to continue charging.

[0017] An embodiment of the present invention further provides a secondary charging method, which uses the above-mentioned secondary charging system for secondary charging. The secondary charging system further includes a second moving structure for controlling the lifting movement of the charging cylinder.

[0018] The secondary charging method includes the following steps:

[0019] Control the charging cylinder loaded with silicon material to enter the single crystal furnace until the convex ring on the charging cylinder contacts the stopper in the auxiliary furnace chamber;

[0020] Control the separation of the quartz cone from the charging cylinder so that the silicon material falls;

[0021] When the falling silicon material is stuck between the feeding cylinder and the quartz cone and thus feeding cannot continue, the first moving structure is used to control the rising of the stopper to drive the feeding cylinder to rise, so as to increase the distance between the quartz cone and the feeding cylinder and continue feeding; or, when the falling silicon material is stuck between the feeding cylinder and the quartz cone and thus feeding cannot continue, the second moving structure is used to control the rising of the feeding cylinder to increase the distance between the quartz cone and the feeding cylinder and continue feeding.

[0022] The beneficial effect of the present invention is that through the arrangement of the first moving structure, the lifting of the stopper can be realized, so as to realize the independent lifting of the feeding cylinder, increase the distance between the feeding cylinder and the quartz cone, solve the problem of material jamming, and will not cause damage to the feeding cylinder. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram showing the secondary feeding system in an embodiment of the present invention Figure 1 ;

[0024] Figure 2 Schematic diagram showing the secondary feeding system in an embodiment of the present invention Figure 2 ;

[0025] Figure 3 Schematic flow chart showing the secondary feeding method in an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the drawings of the embodiments of the present invention. Obviously, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the described embodiments of the present invention fall within the scope of protection of the present invention.

[0027] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0028] Refer to Figure 1, this embodiment provides a secondary feeding system, including a single crystal furnace and a secondary feeding device. The secondary feeding device includes a feeding cylinder 1, a lifting rod 9, and a quartz cone 2. A convex ring 4 is provided on the outer peripheral surface of the feeding cylinder 1. The single crystal furnace includes a main furnace chamber and a secondary furnace chamber. A stopper 5 that cooperates with the convex ring 4 is provided on the inner side wall of the secondary furnace chamber.

[0029] The secondary feeding system further includes a first moving structure, which is used to control the lifting movement of the stopper 5.

[0030] Through the setting of the first moving structure, the lifting of the stopper 5 can be realized, thereby realizing the independent lifting of the feeding cylinder 1, increasing the distance between the feeding cylinder 1 and the quartz cone 2, solving the problem of material jamming, and not causing damage to the feeding cylinder 1.

[0031] In an exemplary embodiment, the first moving structure includes a lead screw 6, and the stopper 5 is helically arranged on the lead screw 6.

[0032] The first moving structure further includes a driving motor for controlling the rotation of the lead screw 6. When material jamming occurs, control the lead screw 6 to rotate so that the stopper 5 rises (i.e., moves away from the quartz cone 2). Since the feeding cylinder 1 is clamped by the convex ring 4 thereon and the stopper 5, the rising of the stopper 5 can drive the feeding cylinder 1 to rise, while the position of the quartz cone 2 remains unchanged. In this way, the distance between the feeding cylinder 1 and the quartz cone 2 can be increased, so that the silicon material can fall smoothly, solving the problem of material jamming, and not causing damage to the feeding cylinder 1.

[0033] Exemplarily, the first moving structure includes at least two lead screws 6 arranged oppositely to keep the stopper 5 always in a horizontal state (i.e., the direction perpendicular to the axial direction of the single crystal furnace) during the lifting process, so that the feeding cylinder 1 rises and falls along the axial direction of the single crystal furnace, avoiding the inclination of the feeding cylinder 1.

[0034] In an exemplary embodiment, a track is provided on the inner side wall of the secondary furnace chamber, and the stopper 5 is movably arranged on the track.

[0035] The setting of the track plays a guiding role and is beneficial to the movement of the stopper 5.

[0036] In an exemplary embodiment, a card slot serving as the track is provided on the inner side wall of the secondary furnace chamber. The extending direction of the card slot is parallel to the axial direction of the single crystal furnace. A protrusion protrudes from the side surface of the stopper 5 for connecting with the inner side wall, and the protrusion is slidably connected in the card slot.

[0037] Exemplarily, the cross-sectional shape of the protrusion in the axial direction of the single crystal furnace is T-shaped to cooperate with the card slot.

[0038] Exemplarily, in a state where no material jamming occurs, the stopper 5 is located at one end of the card slot away from the inlet of the single crystal furnace to ensure the connection stability of the charging cylinder 1.

[0039] Reference Figure 2 In an exemplary embodiment, the secondary charging system further includes a second moving structure for controlling the lifting movement of the charging cylinder 1.

[0040] The setting of the second moving structure can directly control the movement of the charging cylinder 1 and can be used alternately with the first moving structure to increase the service life of the secondary charging system.

[0041] By simultaneously providing the first moving structure and the second moving structure in the secondary charging system, one of the first moving structure and the second moving structure can be used as a spare part for the other. When one of the first moving structure and the second moving structure fails, the other moving structure can be used in time to realize the lifting movement of the charging cylinder 1 to solve the problem of material jamming.

[0042] In an exemplary embodiment, the second moving structure includes a driving part and a transmission connecting part, and the transmission connecting part is connected between the driving part and the charging cylinder 1.

[0043] In an exemplary embodiment, the transmission connecting part includes at least two oppositely arranged transmission connecting rods 8. The transmission connecting rods 8 are connected to the outer peripheral surface of the charging cylinder 1, and the transmission connecting rods 8 are connected to the side of the convex ring 4 away from the quartz cone 2.

[0044] In an exemplary embodiment, the transmission connecting part includes at least two oppositely arranged transmission connecting rods 8. The transmission connecting rods 8 are connected to the side surface of the convex ring 4 away from the quartz cone 2.

[0045] Exemplarily, the lifting rod 9 is inserted into the feeding cylinder 1. The quartz cone 2 is located at the discharging end of the feeding cylinder 1. The side surface of the quartz cone 2 contacts the feeding cylinder 1 to enclose a receiving area for the silicon material 10. A through hole is provided at the top of the quartz cone 2. The lifting rod 9 passes through the through hole and is fixed on both sides of the through hole by bolts, so that the lifting rod 9 and the quartz cone 2 are fixedly connected together. The secondary feeding system further includes a lifting structure 3 connected to the lifting rod 9. The lifting structure 3 controls the secondary feeding device to extend into the single crystal furnace. A quartz crucible 7 is arranged in the single crystal furnace, and a silicon solution is contained in the quartz crucible 7. When the convex ring 4 on the feeding cylinder 1 contacts the stop block 5 on the secondary furnace chamber, the lifting rod 9 is controlled to continue to descend, so that the quartz cone 2 is separated from the feeding cylinder 1, and the silicon material 10 contained in the feeding cylinder 1 falls into the silicon solution.

[0046] When there is a problem that a large piece of silicon material 10 is stuck between the quartz cone 2 and the feeding cylinder 1, the stop block 5 is controlled to rise by the first moving structure to drive the feeding cylinder 1 to rise alone (the position of the quartz cone 2 remains unchanged), or the feeding cylinder 1 is directly controlled to rise by the second moving structure, so as to increase the distance between the quartz cone 2 and the feeding cylinder 1, so that the silicon material 10 can fall smoothly, solving the problem of material jamming while avoiding damage to the feeding cylinder 1.

[0047] It should be noted that Figure 1 and Figure 2 are both schematic diagrams, and only part of the structure of the single crystal furnace is shown in Figure 1 and Figure 2

[0048] Referring to Figure 3 , an embodiment of the present invention further provides a secondary feeding method, which uses the above secondary feeding system for secondary feeding, including the following steps:

[0049] Control the feeding cylinder 1 loaded with silicon material to enter the single crystal furnace until the convex ring 4 on the feeding cylinder 1 contacts the stop block 5 in the secondary furnace chamber;

[0050] Control the quartz cone 2 to be separated from the feeding cylinder 1 so that the silicon material falls;

[0051] When the falling silicon material is stuck between the feeding cylinder 1 and the quartz cone 2 and cannot continue to be fed, the stop block 5 is controlled to rise by the first moving structure to drive the feeding cylinder 1 to rise, so as to increase the distance between the quartz cone 2 and the feeding cylinder 1 and continue to feed.

[0052] ​An embodiment of the present invention further provides a secondary feeding method, which uses the above-mentioned secondary feeding system for secondary feeding. The secondary feeding system further includes a second moving structure for controlling the lifting movement of the feeding cylinder 1.

[0053] The secondary feeding method includes the following steps:

[0054] Control the feeding cylinder 1 loaded with silicon material to enter the single crystal furnace until the convex ring 4 on the feeding cylinder 1 contacts the stopper 5 in the auxiliary furnace chamber;

[0055] Control the separation of the quartz cone 2 from the feeding cylinder 1 so that the silicon material falls;

[0056] When the falling silicon material is stuck between the feeding cylinder 1 and the quartz cone 2 and cannot continue to be fed, control the stopper 5 to rise through the first moving structure to drive the feeding cylinder 1 to rise, so as to increase the distance between the quartz cone 2 and the feeding cylinder 1 and continue feeding; or, when the falling silicon material is stuck between the feeding cylinder 1 and the quartz cone 2 and cannot continue to be fed, control the feeding cylinder 1 to rise through the second moving structure to increase the distance between the quartz cone 2 and the feeding cylinder 1 and continue feeding.

[0057] It can be understood that the above embodiments are only exemplary embodiments adopted to illustrate the principle of the present invention. However, the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also regarded as the protection scope of the present invention.

Claims

1. A secondary feeding system, comprising a single crystal furnace and a secondary feeding device. The secondary feeding device includes a feeding cylinder, a lifting rod, and a quartz cone. A convex ring is provided on the outer peripheral surface of the feeding cylinder. The single crystal furnace includes a main furnace chamber and a secondary furnace chamber. A stop block is provided on the inner side wall of the secondary furnace chamber and is adapted to cooperate with the convex ring. Characterized in that, The secondary feeding system further includes a first moving structure for controlling the lifting movement of the stop block to drive the lifting movement of the feeding cylinder. The first moving structure includes a lead screw, and the stop block is helically arranged on the lead screw, or A track is provided on the inner side wall of the secondary furnace chamber, and the stop block is movably arranged on the track.

2. The secondary feeding system according to claim 1, Characterized in that, A card slot serving as the track is provided on the inner side wall of the secondary furnace chamber. The extending direction of the card slot is parallel to the axial direction of the single crystal furnace. A protrusion is provided on the side surface of the stop block for connecting to the inner side wall, and the protrusion is slidably connected in the card slot.

3. The secondary feeding system according to claim 1, Characterized in that, It further includes a second moving structure for controlling the lifting movement of the feeding cylinder. The second moving structure includes a driving part and a transmission connecting part, and the transmission connecting part is connected between the driving part and the feeding cylinder.

4. The secondary feeding system according to claim 3, Characterized in that, The transmission connecting part includes at least two oppositely arranged transmission connecting rods. The transmission connecting rods are connected to the outer peripheral surface of the feeding cylinder, and the transmission connecting rods are connected to the side of the convex ring away from the quartz cone.

5. The secondary feeding system according to claim 3, Characterized in that, The transmission connecting part includes at least two oppositely arranged transmission connecting rods, and the transmission connecting rods are connected to the side surface of the convex ring away from the quartz cone.

6. A secondary feeding method, Characterized in that, Using the secondary feeding system according to any one of claims 1-5 for secondary feeding, including the following steps: Controlling the feeding cylinder loaded with silicon material to enter the single crystal furnace until the convex ring on the feeding cylinder contacts the stop block in the secondary furnace chamber. Controlling the separation of the quartz cone from the feeding cylinder so that the silicon material falls. When the falling silicon material is stuck between the feeding cylinder and the quartz cone and cannot continue to be fed, controlling the stop block to rise through the first moving structure to drive the feeding cylinder to rise, so as to increase the distance between the quartz cone and the feeding cylinder and continue feeding.

7. A secondary feeding method, Characterized in that, Using the secondary feeding system according to any one of claims 1-5 for secondary feeding. The secondary feeding system further includes a second moving structure for controlling the lifting movement of the feeding cylinder. The secondary feeding method includes the following steps: Controlling the feeding cylinder loaded with silicon material to enter the single crystal furnace until the convex ring on the feeding cylinder contacts the stop block in the secondary furnace chamber. Controlling the separation of the quartz cone from the feeding cylinder so that the silicon material falls. When the falling silicon material is clamped between the feeding cylinder and the quartz cone and thus feeding cannot continue, the first moving structure is used to control the lifting of the stopper to drive the feeding cylinder to rise, so as to increase the distance between the quartz cone and the feeding cylinder and continue feeding; or, when the falling silicon material is clamped between the feeding cylinder and the quartz cone and thus feeding cannot continue, the second moving structure is used to control the lifting of the feeding cylinder to increase the distance between the quartz cone and the feeding cylinder and continue feeding.

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