Crystal lifting and rotating structure with weight checking function for fluorination furnace

Abstract

The invention provides a crystal lifting and rotating structure with a weight checking function for a fluorination furnace, which comprises a seed crystal lifting structure, a seed crystal rotating structure and a seed crystal weighing structure, the seed crystal lifting structure is mounted on a seed crystal base, and a lifting power output shaft of the seed crystal lifting structure is connected with a lifting screw rod through a coupler; a nut of the lifting screw rod is connected with a seed crystal lifting seat, and lifting guide rails are mounted on two sides of the seed crystal lifting seat and are mounted on a seed crystal base; the seed crystal rotating structure is located on the seed crystal lifting seat and comprises an outer rotating shaft, and a movable flange, a driven belt wheel, a spacer sleeve, an upper bearing, a bearing seat, a lower bearing, a bearing pressing block, a lower screwing sleeve, a locking nut and a hoop are sequentially and coaxially mounted on the outer side of the outer rotating shaft from top to bottom; wherein the upper end face of the movable flange and the upper end face of the driven belt wheel abut against two steps on the outer rotating shaft respectively, a flat key is installed between the driven belt wheel and the outer rotating shaft, and the bearing seat is coaxially installed in two coaxial holes in the seed crystal lifting seat.

Description

Technical Field

[0001] The invention relates to the field of semiconductors, and in particular to a crystal lifting and rotating structure with a weight checking function for a fluorination furnace. Background Art

[0002] The existing Czochralski method for crystal growth usually involves a rotating seed crystal rod directly connected to the seed crystal, which makes it difficult to measure the quality of the growing crystal alone, and also makes it impossible to include changes in crystal growth quality in the crystal growth process control. Even if the existing crystal is weighed, it is outside the cavity and is greatly affected by the external environment, making it difficult to achieve accurate quality measurement. Summary of the invention

[0003] In view of the problems existing in the prior art, the present invention provides a crystal lifting and rotating structure with a weight checking function for a fluorination furnace to solve at least one of the above technical problems.

[0004] The technical solution of the present invention is: a crystal lifting and rotating structure with a weight checking function for a fluorination furnace, characterized in that it comprises a seed crystal pulling structure, a seed crystal rotating structure and a seed crystal weighing structure, the seed crystal pulling structure is installed on a seed crystal base, the output shaft of the pulling power of the seed crystal pulling structure is connected to the pulling screw rod through a coupling, the nut of the pulling screw rod is connected to the seed crystal lifting seat, and lifting guide rails are installed on both sides of the seed crystal lifting seat, and the lifting guide rails are installed on the seed crystal base;

[0005] The seed crystal rotating structure is located on the seed crystal lifting seat, and the seed crystal rotating structure includes an outer rotating shaft, and a movable flange, a driven pulley, a spacer sleeve, an upper bearing, a bearing seat, a lower bearing, a bearing block, a lower tightening sleeve, a locking nut and a clamp are coaxially installed on the outer side of the outer rotating shaft from top to bottom, wherein the upper end faces of the movable flange and the driven pulley are respectively against two steps on the outer rotating shaft, a flat key is installed between the driven pulley and the outer rotating shaft, and the bearing seat is coaxially installed in two coaxial holes on the seed crystal lifting seat and is locked and fixed by screws;

[0006] The seed crystal weighing structure includes a weighing instrument and a constant temperature chamber. The weighing instrument is coaxially installed on the outer rotating shaft through a sealing ring and is fixedly connected to a movable flange. The side of the movable flange is locked with a top screw to ensure that there is no relative rotation between it and the outer rotating shaft. The constant temperature chamber is fixed on the seed crystal lifting seat. The upper end of the weighing instrument leads out through a sliding wire ring, and the outlet end of the weighing instrument and the constant temperature chamber are relatively fixed.

[0007] The present invention uses the synchronous rotation of the weighing instrument and the external rotating shaft; through this connection, the internal sensor of the weighing instrument is placed in the vacuum chamber, and the constant temperature chamber provides a constant temperature environment for the weighing instrument to ensure high weighing accuracy. The present invention improves the weighing accuracy and realizes the process requirements of controlling crystal growth through multiple weighing.

[0008] Further preferably, the clamp is clamped in a groove on the outer rotating shaft, the outer side of the lower tightening sleeve is a threaded structure, and a flat key is installed between the inner side of the lower tightening sleeve and the outer rotating shaft.

[0009] Ensure relative stability.

[0010] Further preferably, the locking nut is matched with the thread of the lower rotating sleeve, and the outer rotating shaft is pulled down by tightening the thread, so that the spacer sleeve and the lower tightening sleeve respectively press the upper and lower bearings of the bearing seat.

[0011] Further preferably, the seed crystal rotating structure also includes a rotating power, and a driving pulley is installed on the output shaft of the rotating power, and the power is transmitted to the driven pulley through a belt, thereby driving the outer rotating shaft to rotate.

[0012] Further preferably, a magnetic fluid is coaxially sealed on the outer side of the outer rotating shaft, the magnetic fluid is fixed on the seed crystal lifting seat through a support and a magnetic fluid seat, the lower side of the magnetic fluid is fixed to the upper end surface of the bellows, the lower end surface of the bellows is fixed to the sealed cavity, and the two mounting surfaces are sealed by a sealing ring, thereby forming a sealed cavity.

[0013] Further preferably, a connecting hole for a protective gas introduction pipe is provided on the magnetic fluid seat.

[0014] Further preferably, the bearing of the bearing seat and the bearing of the magnetic fluid work together to expand the fixed length of the external rotating shaft, thereby ensuring that the external rotating shaft rotates more smoothly.

[0015] Preferably, a sensor is provided inside the weighing instrument, the lower end of the sensor is threadedly connected to the upper end of a seed crystal rod, the lower end of the seed crystal rod is connected to the seed crystal, the seed crystal rod is relatively fixed to the weighing instrument and is coaxial with the external rotating shaft, so that the seed crystal rod rotates synchronously.

[0016] Further preferably, the seed crystal weighing structure further comprises an end inner seal and an end seal, the outer side of the end inner seal is a threaded structure, and the outer side of the end inner seal and the inner threaded structure at the lower end of the outer rotating shaft are screwed together, and the end inner seal is drilled with evenly distributed small holes for ventilation.

[0017] Further preferably, a small gap is left between the end inner seal and the seed crystal rod to ensure the stability of the seed crystal rod rotation.

[0018] Further preferably, the end seal is coaxially mounted on the seed crystal rod through a top screw, and a micrometer-level gap is left between the end seal and the end inner seal, thereby reducing the airflow in the vacuum chamber flowing into the outer rotating shaft and reducing the contamination of the weighing sensor.

[0019] Further preferably, the weighing instrument is directly connected to the crystal through the seed crystal rod. Detection and crystal growth are in the same workspace, so that the real-time monitoring of the crystal weight change during the crystal growth process can be achieved, and the crystal growth process can be formulated according to the change in crystal quality.

[0020] The present invention improves weighing accuracy by connecting the lower end of the seed crystal rod to the seed crystal and the upper end to the screw rod extending from the weighing instrument, thereby realizing the process requirements of controlling crystal growth through multiple weighings; an outer rotating shaft is coaxially installed on the outer side of the seed crystal rod, a vacuum chamber is formed on the inner side of the outer rotating shaft, a pulley is coaxially installed on the outer rotating shaft, and the rotating structure and the weighing structure are relatively independent; the rotation is driven by a high-precision power mechanism, and a bearing seat and a magnetic fluid are coaxially installed with the outer rotating shaft to ensure stable rotation of the outer rotating shaft and provide vacuum sealing.

[0021] Beneficial effects:

[0022] 1. The weighing module is built into the vacuum chamber to ensure weighing accuracy;

[0023] 2. The seed crystal rotation is divided into two layers, inner and outer, which separates the weighing structure from the outer rotating structure;

[0024] 3. The inner layer of the outer rotating shaft is a vacuum layer, with a built-in seed crystal lifting rod to connect the seed crystal. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the seed crystal lifting and rotating structure of the present invention;

[0026] Figure 2 This is a schematic diagram of the seed crystal rotation structure of the present invention;

[0027] Figure 3 This is a partial enlarged view of the seed crystal rotation structure of the present invention;

[0028] Figure 4 This is a schematic diagram of the seed crystal weighing structure of the present invention;

[0029] Figure 5 It is a schematic diagram of the overall structure of the present invention.

[0030] In the figure: 1. seed crystal base; 2. lifting power; 3. coupling; 4. lifting screw rod; 5. seed crystal lifting seat; 6. lifting guide rail; 7. external rotating shaft; 8. bearing seat; 8.1. upper bearing; 8.2. lower bearing; 9. flat key; 10. driven pulley; 11. spacer sleeve; 12. bearing block; 13. lower tightening sleeve; 14. locking nut; 15. clamp; 16. movable flange; 17. rotating power; 18. driving pulley; 19. belt; 20. magnetic fluid; 21. pillar; 22. magnetic fluid seat; 23. bellows; 24. weighing instrument; 25. constant temperature chamber; 26. seed crystal rod; 27. end inner seal; 28. end seal. DETAILED DESCRIPTION

[0031] The present invention will be further described below in conjunction with the accompanying drawings.

[0032] Reference Figure 1-Figure 5 As shown, a crystal lifting and rotating structure with a weight checking function for a fluorination furnace includes a seed crystal pulling structure, a seed crystal rotating structure and a seed crystal weighing structure. The seed crystal pulling structure is installed on a seed crystal base. The output shaft of the pulling power 2 of the seed crystal pulling structure is connected to the pulling screw 4 through a coupling 3. The nut of the pulling screw is connected to a seed crystal lifting seat 5. Lifting guide rails 6 are installed on both sides of the seed crystal lifting seat. The lifting guide rails are installed on the seed crystal base 1; the seed crystal rotating structure is located on the seed crystal lifting seat. The seed crystal rotating structure includes an outer rotating shaft 7. The outer side of the outer rotating shaft is coaxially installed with a movable flange 16, a driven pulley 10, a spacer sleeve 11, an upper bearing 8.1, a bearing seat 8, and a lower bearing 8.2 in sequence from top to bottom. , bearing block 12, lower tightening sleeve 13, locking nut 14 and clamp 15, wherein the upper end faces of the movable flange and the driven pulley are respectively against the two steps on the outer rotating shaft, a flat key 9 is installed between the driven pulley and the outer rotating shaft, the bearing seat is coaxially installed in two coaxial holes on the seed crystal lifting seat, and is locked and fixed by screws; the seed crystal weighing structure includes a weighing instrument 24 and a constant temperature chamber 25, the weighing instrument is coaxially installed on the outer rotating shaft through a sealing ring, and is connected and fixed with the movable flange, the side of the movable flange is locked with a top screw to ensure that there is no relative rotation between it and the outer rotating shaft, the constant temperature chamber is fixed on the seed crystal lifting seat, the upper end of the weighing instrument leads out through a sliding wire ring, and the outlet end of the weighing instrument and the constant temperature chamber are relatively fixed.

[0033] The present invention uses the synchronous rotation of the weighing instrument and the external rotating shaft; through this connection, the internal sensor of the weighing instrument is placed in the vacuum chamber, and the constant temperature chamber provides a constant temperature environment for the weighing instrument to ensure high weighing accuracy. The present invention improves the weighing accuracy and realizes the process requirements of controlling crystal growth through multiple weighing.

[0034] Further preferably, the clamp is clamped in the groove on the outer rotating shaft, the outer side of the lower tightening sleeve is a threaded structure, and a flat key is installed between the inner side of the lower tightening sleeve and the outer rotating shaft to ensure relative fixation.

[0035] Further preferably, the locking nut is matched with the thread of the lower rotating sleeve, and the outer rotating shaft is pulled down by tightening the thread, so that the spacer sleeve and the lower tightening sleeve respectively press the upper and lower bearings of the bearing seat.

[0036] Further preferably, the seed crystal rotating structure also includes a rotating power 17, and a driving pulley 18 is installed on the output shaft of the rotating power, and the power is transmitted to the driven pulley through a belt 19, thereby driving the outer rotating shaft to rotate.

[0037] Further preferably, a magnetic fluid 20 is coaxially sealed and installed outside the outer rotating shaft, the magnetic fluid is fixed on the seed crystal lifting seat through a support 21 and a magnetic fluid seat 22, the lower part of the magnetic fluid is fixed to the upper end surface of the bellows 23, the lower end surface of the bellows is fixed to the sealing cavity, and the two mounting surfaces are sealed by a sealing ring, thereby forming a sealed cavity.

[0038] Further preferably, a connection hole for a protective gas introduction pipe is provided on the magnetic fluid seat.

[0039] Further preferably, the bearing of the bearing seat and the bearing of the magnetic fluid work together to increase the fixed length of the external rotating shaft, thereby ensuring that the external rotating shaft rotates more smoothly.

[0040] Preferably, a sensor is provided inside the weighing instrument, the lower end of the sensor is threadedly connected to the upper end of a seed crystal rod 26, the lower end of the seed crystal rod is connected to the seed crystal, the seed crystal rod is relatively fixed to the weighing instrument and is coaxial with the external rotating shaft, so that the seed crystal rod rotates synchronously.

[0041] Further preferably, the seed crystal weighing structure further includes an end inner seal 27 and an end seal 28, the outer side of the end inner seal is a threaded structure, and the outer side of the end inner seal and the inner thread structure at the lower end of the outer rotating shaft are screwed together, and uniformly distributed small holes are drilled on the end inner seal. The small holes are used for ventilation.

[0042] Further preferably, a small gap is left between the end inner seal and the seed crystal rod to ensure the stability of the rotation of the seed crystal rod.

[0043] Further preferably, the end seal is coaxially mounted on the seed crystal rod through a top screw, and a micrometer-level gap is left between the end seal and the end inner seal, thereby reducing the airflow in the vacuum chamber flowing into the outer rotating shaft and reducing the pollution of the weighing sensor.

[0044] Further preferably, the weighing instrument is directly connected to the crystal through the seed crystal rod. The detection and crystal growth are in the same workspace, so that the real-time monitoring of the crystal weight change during the crystal growth process can be achieved, and the crystal growth process can be formulated according to the change of crystal quality.

[0045] The present invention improves weighing accuracy by connecting the lower end of the seed crystal rod to the seed crystal and the upper end to the screw rod extending from the weighing instrument, thereby realizing the process requirements of controlling crystal growth through multiple weighings; an outer rotating shaft is coaxially installed on the outer side of the seed crystal rod, a vacuum chamber is formed on the inner side of the outer rotating shaft, a pulley is coaxially installed on the outer rotating shaft, and the rotating structure and the weighing structure are relatively independent; the rotation is driven by a high-precision power mechanism, and a bearing seat and a magnetic fluid are coaxially installed with the outer rotating shaft to ensure stable rotation of the outer rotating shaft and provide vacuum sealing.

[0046] Beneficial effects:

[0047] 4. The weighing module is built into the vacuum chamber to ensure weighing accuracy;

[0048] 5. The seed crystal rotation is divided into two layers, inner and outer, separating the weighing structure and the outer rotating structure;

[0049] The inner layer of the outer rotating shaft is a vacuum layer, with a built-in seed crystal lifting rod to connect the seed crystal.

[0050] The above are only preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A crystal lifting and rotating structure with weight checking function for a fluorination furnace, characterized in that: It includes a seed crystal lifting structure, a seed crystal rotating structure and a seed crystal weighing structure, wherein the seed crystal lifting structure is installed on a seed crystal base, the output shaft of the pulling power of the seed crystal lifting structure is connected to a pulling screw rod through a coupling, the nut of the pulling screw rod is connected to a seed crystal lifting seat, and lifting guide rails are installed on both sides of the seed crystal lifting seat, and the lifting guide rails are installed on the seed crystal base; The seed crystal rotating structure is located on the seed crystal lifting seat, and the seed crystal rotating structure includes an outer rotating shaft, and a movable flange, a driven pulley, a spacer sleeve, an upper bearing, a bearing seat, a lower bearing, a bearing block, a lower tightening sleeve, a locking nut and a clamp are coaxially installed on the outer side of the outer rotating shaft from top to bottom, wherein the upper end faces of the movable flange and the driven pulley are respectively against two steps on the outer rotating shaft, a flat key is installed between the driven pulley and the outer rotating shaft, and the bearing seat is coaxially installed in two coaxial holes on the seed crystal lifting seat and is locked and fixed by screws; The seed crystal weighing structure includes a weighing instrument and a constant temperature chamber. The weighing instrument is coaxially installed on the outer rotating shaft through a sealing ring and is fixedly connected to a movable flange. The side of the movable flange is locked with a top screw to ensure that there is no relative rotation between it and the outer rotating shaft. The constant temperature chamber is fixed on the seed crystal lifting seat. The upper end of the weighing instrument leads out through a sliding wire ring, and the outlet end of the weighing instrument and the constant temperature chamber are relatively fixed.

2. The crystal lifting and rotating structure with weight checking function for a fluorination furnace according to claim 1, characterized in that: The clamp is clamped in the groove on the outer rotating shaft, the outer side of the lower tightening sleeve is a threaded structure, and a flat key is installed between the inner side of the lower tightening sleeve and the outer rotating shaft.

3. The crystal lifting and rotating structure with weight checking function for a fluorination furnace according to claim 1, characterized in that: The locking nut is matched with the thread of the lower rotating sleeve. By tightening the thread, the outer rotating shaft is pulled down, so that the spacing sleeve and the lower tightening sleeve respectively press the upper and lower bearings of the bearing seat.

4. The crystal lifting and rotating structure with weight checking function for a fluorination furnace according to claim 1, characterized in that: The seed crystal rotating structure also includes a rotating power, and a driving pulley is installed on the output shaft of the rotating power, and the power is transmitted to the driven pulley through a belt, thereby driving the outer rotating shaft to rotate.

5. The crystal lifting and rotating structure with weight checking function for a fluorination furnace according to claim 1, characterized in that: A magnetic fluid is coaxially sealed on the outer side of the outer rotating shaft, and the magnetic fluid is fixed on the seed crystal lifting seat through a support and a magnetic fluid seat. The lower side of the magnetic fluid is fixed to the upper end surface of the bellows, and the lower end surface of the bellows is fixed to the sealing cavity. The two mounting surfaces are sealed by a sealing ring.

6. The crystal lifting and rotating structure with weight checking function for a fluorination furnace according to claim 5, characterized in that: The magnetic fluid seat is provided with a connecting hole for a protective gas introduction pipe.

7. The crystal lifting and rotating structure with weight checking function for a fluorination furnace according to claim 1, characterized in that: A sensor is arranged inside the weighing instrument, the lower end of the sensor is threadedly connected to the upper end of a seed crystal rod, the lower end of the seed crystal rod is connected to the seed crystal, the seed crystal rod is relatively fixed to the weighing instrument and is coaxial with the external rotating shaft.

8. The crystal lifting and rotating structure with weight checking function for a fluorination furnace according to claim 7, characterized in that: The seed crystal weighing structure also includes an end inner seal and an end seal. The outer side of the end inner seal is a threaded structure, and the outer side of the end inner seal and the internal thread structure at the lower end of the external rotating shaft are screwed together, and evenly distributed small holes are drilled on the end inner seal.

9. The crystal lifting and rotating structure with weight checking function for a fluorination furnace according to claim 8, characterized in that: A small gap is left between the end inner seal and the seed crystal rod.

10. The crystal lifting and rotating structure with weight checking function for a fluorination furnace according to claim 8, characterized in that: The end seal is coaxially mounted on the seed crystal rod through a top screw, and a micrometer-level gap is left between the end seal and the end inner seal.

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