Impurity removing device for semiconductor silicon crystal smelting

Abstract

The utility model discloses an impurity removal device for semiconductor silicon crystal smelting, which comprises a pretreatment shell capable of reciprocating along the transverse direction, the pretreatment shell is positioned above a fixedly arranged smelting furnace shell, the front side and the rear side of the pretreatment shell are respectively and fixedly provided with a sliding block, and the sliding blocks are arranged on a linear sliding rail in a sliding manner; a spraying head is arranged at the upper part of the inner cavity of the pretreatment shell and is mounted at the tail end of the pickling inlet pipe; a tee joint communicated with an inner cavity of the pretreatment shell is mounted at the bottom of the pretreatment shell, a gate valve is mounted at a bottom port of the tee joint, a side port of the tee joint is connected with a drain pipe, and a drain valve is mounted at the joint; and the bottom of the gate valve is connected with a feeding hole in the top of the smelting furnace shell through a flange. According to the impurity removing device for semiconductor silicon crystal smelting, the impurity removing effect can be improved, and the problem that the material utilization rate is low is solved.

Description

Technical Field

[0001] This utility model relates to an impurity removal device for semiconductor silicon crystal melting, belonging to the field of silicon crystal melting technology. Background Technology

[0002] Melting and impurity removal of semiconductor silicon crystals are key steps in manufacturing high-purity silicon materials, directly affecting the performance of semiconductor devices.

[0003] The smelting and purification of polycrystalline silicon raw materials often employs directional solidification purification. Directional solidification utilizes the significant difference in segregation coefficients between silicon and metallic impurities in polycrystalline silicon raw materials. During solidification, the molten silicon at the bottom of the quartz crucible begins to solidify first. To achieve segregation equilibrium, impurities with lower segregation coefficients diffuse and separate from the solidified silicon into the liquid state and accumulate there. As solidification continues, the concentration of metallic impurities in the liquid state increases, eventually solidifying at the top of the ingot. Finally, the end with higher metallic impurity content is removed, resulting in a purified polycrystalline silicon ingot.

[0004] However, based on practical experience, the directional solidification purification method still has the following technical problems:

[0005] Due to the limitations of the segregation coefficient, impurities with a segregation coefficient close to 1 (such as boron) are difficult to be effectively removed during the solidification process, resulting in limited impurity removal and low purification efficiency.

[0006] During directional solidification, a large area containing many impurities needs to be removed, which reduces the overall material utilization rate and increases waste and production costs.

[0007] In conclusion, the existing technology obviously has inconveniences and defects in practical use, so it is necessary to improve it. Utility Model Content

[0008] This invention addresses the shortcomings of the prior art by providing an impurity removal device for semiconductor silicon crystal melting, which not only improves the impurity removal effect but also solves the problem of low material utilization.

[0009] To solve the above technical problems, the present invention adopts the following technical solution:

[0010] An impurity removal device for semiconductor silicon crystal melting includes a pretreatment shell that can reciprocate laterally. The pretreatment shell is located above a fixed melting furnace shell. Slider blocks are fixedly installed on the front and rear sides of the pretreatment shell, and the sliders are slidably mounted on linear guide rails. A spray head is installed in the upper part of the inner cavity of the pretreatment shell, and the spray head is installed at the end of the pickling inlet pipe. A tee is installed at the bottom of the pretreatment shell and communicates with its inner cavity. A gate valve is installed at the bottom port of the tee, and a drain valve is installed at the side port of the tee. The bottom of the gate valve is connected to the feed inlet at the top of the melting furnace shell through a flange.

[0011] Furthermore, the top of the pretreatment shell is equipped with an openable top cover.

[0012] Furthermore, the linear guide rails are arranged side by side along the horizontal direction.

[0013] Furthermore, the side of the slider is connected to a telescopic cylinder, which provides power for the lateral reciprocating movement of the pretreatment shell along the linear slide rail.

[0014] Furthermore, the pickling inlet pipe is installed horizontally through the side wall of the pretreatment shell.

[0015] Furthermore, an openable sealing cover is installed on the top of the smelting furnace shell, and a feed inlet is provided at the center of the top of the sealing cover.

[0016] Furthermore, a quartz crucible is installed inside the furnace shell, and an induction coil is installed around the quartz crucible.

[0017] Furthermore, the bottom of the quartz crucible is connected to a liftable water-cooled ingot pulling mechanism, which is internally circulated with cooling water.

[0018] Compared with the prior art, the present invention, by adopting the above technical solution, has the following advantages:

[0019] This invention combines pickling with directional solidification technology. First, pickling is used to remove impurities from the surface of the silicon material, and then directional solidification is performed. After solidification, the area containing impurities needs to be removed, thus improving the utilization rate of the material. This invention, by combining pickling with directional solidification technology, can significantly improve the removal effect of impurities.

[0020] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of this utility model;

[0022] Figure 2 This is a schematic diagram of the pre-processed shell driven laterally.

[0023] In the figure, 1-pretreatment shell, 2-slider, 3-telescopic cylinder, 4-linear slide rail, 5-spray head, 6-pickling inlet pipe, 7-top cover, 8-teet, 9-gate valve, 10-drain pipe, 11-drain valve, 12-melting furnace shell, 13-sealing cover, 14-quartz crucible, 15-water-cooled ingot pulling mechanism. Detailed Implementation

[0024] To provide a clearer understanding of the technical features, objectives, and effects of this utility model, the specific embodiments of this utility model are now described with reference to the accompanying drawings.

[0025] like Figure 1 and Figure 2 As shown in the figure, this utility model provides an impurity removal device for semiconductor silicon crystal melting, including a pretreatment shell 1 that can move laterally back and forth, and an openable top cover 7 on the top of the pretreatment shell 1 to facilitate the introduction of silicon material.

[0026] The pretreatment shell 1 is located above the fixedly installed smelting furnace shell 12. Slider 2 is fixedly installed on the front and rear sides of the pretreatment shell 1, and the slider 2 is slidably mounted on the linear slide rail 4. The linear slide rail 4 is arranged side by side in the horizontal direction, and the side of the slider 2 is connected to the telescopic cylinder 3. The telescopic cylinder 3 provides power for the lateral reciprocating movement of the pretreatment shell 1 along the linear slide rail 4.

[0027] The upper part of the inner cavity of the pretreatment shell 1 is provided with a spray head 5, which is installed at the end of the pickling inlet pipe 6. The pickling inlet pipe 6 is arranged to penetrate the side wall of the pretreatment shell 1 in a horizontal direction. The spray head 5 is used to pickle impurities on the surface of the silicon material.

[0028] The bottom of the pretreatment shell 1 is equipped with a tee 8 that communicates with its inner cavity. The top port of the tee 8 is connected to the bottom of the pretreatment shell 1, and a gate valve 9 is installed at the bottom port of the tee 8. The side port of the tee 8 is connected to the drain pipe 10, and a drain valve 11 is installed at the connection. The drain valve 11 is used for the output of pickling waste liquid.

[0029] The bottom of the gate valve 9 is connected to the feed inlet at the top of the smelting furnace shell 12 via a flange.

[0030] The top of the smelting furnace shell 12 is equipped with an openable sealing cover 13. A feed inlet is provided at the center of the top of the sealing cover 13. The feed inlet is used to introduce the pickled silicon material into the smelting furnace shell 12.

[0031] A quartz crucible 14 is installed inside the furnace shell 12. An induction coil is installed around the quartz crucible 14. When the induction coil is energized, heat is transferred to the quartz crucible 14 to melt the silicon material.

[0032] The bottom of the quartz crucible 14 is connected to a liftable water-cooled ingot pulling mechanism 15, which is equipped with circulating cooling water. During its descent, the water-cooled ingot pulling mechanism 15 gradually pulls the quartz crucible 14 out of the hot zone, causing the polycrystalline silicon inside the quartz crucible 14 to solidify in a directional manner.

[0033] The specific working principle of this utility model is as follows:

[0034] Silicon material is placed inside the pretreatment shell 1. Pickling solution enters the spray head 5 from the pickling inlet pipe 6. The spray head 5 sprays impurities on the surface of the silicon material to pickle it. The pickling waste liquid is collected in the tee 8 and discharged through the drain pipe 10. After pickling, the gate valve 9 is opened, and the silicon material enters the quartz crucible 14 from the top feed port of the melting furnace shell 12. The induction coil is energized to transfer heat to the quartz crucible 14 to melt the silicon material. After melting, the water-cooled ingot pulling mechanism 15 gradually pulls the quartz crucible 14 out of the hot zone, so that the polycrystalline silicon in the quartz crucible 14 is directionally solidified. During the directional solidification process, metal impurities are collected at the top of the ingot. Finally, the flange between the bottom of the gate valve 9 and the feed port of the melting furnace shell 12 is disassembled, and the telescopic cylinder 3 drives the pretreatment shell 1 to move along the linear slide rail 4 to avoid the opening of the sealing cover 13, so that the polycrystalline silicon ingot in the quartz crucible 14 can be taken out from the sealing cover 13.

[0035] The above description provides examples of the preferred embodiments of this utility model. Any aspects not detailed herein are common knowledge to those skilled in the art. The scope of protection of this utility model is determined by the claims. Any equivalent modifications based on the technical teachings of this utility model are also within the scope of protection of this utility model.

Claims

1. An impurity removal device for semiconductor silicon crystal melting, characterized in that: The application relates to a smelting furnace, which comprises a pre-treatment shell (1) capable of moving reciprocally along the transverse direction, wherein the pre-treatment shell (1) is arranged above a fixedly arranged smelting furnace shell (12), sliding blocks (2) are fixedly arranged on the front and back sides of the pre-treatment shell (1) respectively, the sliding blocks (2) are slidingly arranged on linear sliding rails (4), a spraying head (5) is arranged on the inner cavity of the upper portion of the pre-treatment shell (1), the spraying head (5) is arranged at the tail end of an acid pickling inlet pipe (6), a three-way pipe (8) is arranged at the bottom of the pre-treatment shell (1) and is connected with the inner cavity of the pre-treatment shell (1), a gate valve (9) is arranged at the bottom end of the three-way pipe (8), a side end of the three-way pipe (8) is connected with a liquid discharge pipe (10), a liquid discharge valve (11) is arranged at the connecting position, the bottom of the gate valve (9) is connected with the feed inlet of the top portion of the smelting furnace shell (12) through flanges.

2. The impurity removal apparatus for semiconductor silicon crystal melting according to claim 1, wherein: An openable top cover (7) is arranged at the top of the pre-treatment shell (1).

3. The impurity removal apparatus for semiconductor silicon crystal melting according to claim 1, wherein: The linear sliding rails (4) are arranged side by side along the horizontal direction.

4. The impurity removal apparatus for semiconductor silicon crystal melting according to claim 3, wherein: The side of the sliding block (2) is connected with a telescopic cylinder (3), the telescopic cylinder (3) provides power for the transverse reciprocating movement of the pre-treatment shell (1) along the linear sliding rails (4).

5. The impurity removal apparatus for semiconductor silicon crystal melting according to claim 1, wherein: The acid pickling inlet pipe (6) is arranged through the side wall of the pre-treatment shell (1) along the horizontal direction.

6. The impurity removal apparatus for semiconductor silicon crystal melting according to claim 1, wherein: An openable sealing cover (13) is arranged at the top of the smelting furnace shell (12), and a feed inlet is arranged at the central position of the top of the sealing cover (13).

7. The impurity removal apparatus for semiconductor silicon crystal melting according to claim 1, wherein: A quartz crucible (14) is arranged in the inner cavity of the smelting furnace shell (12), and an induction coil is arranged around the quartz crucible (14).

8. The impurity removal apparatus for semiconductor silicon crystal melting according to claim 7, wherein: The bottom of the quartz crucible (14) is connected with a water-cooled ingot pulling mechanism (15) capable of lifting, and circulating cooling water is arranged in the water-cooled ingot pulling mechanism (15).

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