Rotary lifting shaft of rotary lifting system of Czochralski single crystal furnace

Abstract

The utility model belongs to the field of photovoltaic solar energy and semiconductors, and particularly relates to a rotary lifting shaft of a rotary lifting system of a czochralski single crystal furnace. The rotary lifting shaft of the rotary lifting system of the Czochralski single crystal furnace comprises a lifting shaft body and is characterized in that thermal barrier coatings are arranged at the upper end and the outer surface of the lifting shaft body; according to the utility model, the rotary lifting shaft is improved, and the upper end and the surface of the lifting shaft body are provided with the thermal barrier coatings, so that the thermal insulation capacity of the joint of the lifting shaft body and the graphite support rod is improved, the service life of the rotary lifting shaft is prolonged, the later maintenance frequency is reduced, and the maintenance cost of equipment is reduced.

Description

Technical Field

[0001] The utility model belongs to the field of photovoltaic solar energy and semiconductors, and particularly relates to a rotary lifting shaft of a rotary lifting system of a CZ single crystal furnace. Background Art

[0002] In many applications of CZ silicon single crystal growth furnaces, in order to meet the needs of crystal growth, the temperature of the main furnace chamber and the part in contact with the main furnace chamber is relatively high; the upper end of the rotary lifting shaft is directly in contact with the graphite support rod in the main furnace chamber, and the temperature of the contact area is relatively high, while the lower end of the shaft is directly in contact with the air and cooling water circuit, and the temperature is relatively low. Therefore, the rotary lifting shaft is subjected to relatively large thermal stress, and often fails due to thermal stress cracks.

[0003] Moreover, due to long-term high-temperature contact, the hot end of the rotating lifting shaft and the graphite support rod are prone to surface adhesion, making maintenance and replacement difficult. Summary of the invention

[0004] In view of the shortcomings of the prior art, the utility model improves the rotary lifting shaft by providing a thermal barrier coating on the upper end and surface of the lifting shaft body, thereby improving the thermal insulation capacity of the connection between the lifting shaft body and the graphite support rod, thereby extending the service life of the rotary lifting shaft, reducing the number of subsequent maintenance, and reducing the maintenance cost of the equipment.

[0005] The technical solution of the utility model is as follows:

[0006] The rotary lifting shaft of the rotary lifting system of the CZ single crystal furnace comprises a lifting shaft body, which is characterized in that a thermal barrier coating is provided on the upper end and the outer surface of the lifting shaft body.

[0007] Furthermore, a tapered hole is provided at the upper end of the lifting shaft, and a thermal barrier coating is also provided on the inner wall of the tapered hole.

[0008] Furthermore, a cooling water channel hole is provided on the lower end surface of the lifting shaft.

[0009] Furthermore, the end of the cooling water channel hole located inside the lifting shaft body is spherical.

[0010] Furthermore, the thermal barrier coating is an oxide coating, a nitride coating, a carbide coating or a boride coating.

[0011] Furthermore, the oxide coating is a zirconium oxide coating, a yttrium oxide coating, an aluminum oxide coating, or a tin oxide coating.

[0012] Furthermore, the nitride coating is a boron nitride coating, a silicon nitride coating or a titanium nitride coating.

[0013] Furthermore, the carbide coating is a titanium carbide coating.

[0014] Furthermore, the boride coating is a zirconium boride coating.

[0015] Furthermore, the thickness of the thermal barrier coating is 100-800 μm.

[0016] In summary, the utility model has the following beneficial effects:

[0017] The utility model improves the structure of the rotating lifting shaft, and the thermal barrier coating arranged effectively isolates the high temperature of the graphite support rod, thereby avoiding the problem of cracking of the rotating lifting shaft due to thermal stress, extending the service life after rotation and lifting, and reducing the later maintenance cost; further, the thermal barrier coating avoids the adhesion between the rotating lifting shaft and the graphite support rod, and can be easily removed for replacement, reducing the difficulty and maintenance cost of equipment maintenance; further, the thermal barrier coating effectively reduces the temperature difference between the high temperature and low temperature ends, thereby reducing the thermal stress of the rotating lifting shaft, avoiding crack failure inside the material, and also significantly reducing the temperature of the high temperature end of the rotating lifting shaft, effectively reducing the heat carried away by the circulating cooling water, and having a significant energy-saving effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the structure of the rotating lifting system of the CZ single crystal furnace;

[0019] Figure 2 It is a structural schematic diagram of a rotating lifting shaft;

[0020] In the figure, 1 is the lifting shaft.

[0021] 2 is the cooling water hole,

[0022] 3 is thermal barrier coating,

[0023] 4 is a tapered hole. DETAILED DESCRIPTION

[0024] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0025] It should be noted that when an element is referred to as being "disposed on" or "fixed on" another element, it may be directly on the other element or there may be a central element. When an element is referred to as being "fixed on" another element, or "fixedly connected" to another element, they may be fixed in a detachable manner or in a non-detachable manner. When an element is considered to be "connected" or "rotatably connected" to another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right", "upper", "lower" and similar expressions used are for illustrative purposes only and do not represent the only implementation method.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to restrict the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0027] The terms “first”, “second”, “third” and the like in the present invention do not represent specific quantities and orders, but are merely used to distinguish names.

[0028] like Figure 1 The rotary lifting system of the vertical pulling single crystal furnace shown in the figure has various components supported by a base, the lifting motor drives the lead screw to rotate, and the support frame is driven by the lead screw to move up and down along the guide rail. A rotary motor and a magnetic fluid are provided on the support frame, and the rotary lifting shaft is connected in the magnetic fluid and rotates under the action of the rotary motor.

[0029] See also Figure 2 As shown, the rotary lifting shaft of the rotary lifting system of the CZ single crystal furnace comprises a lifting shaft body 1, and the upper end and outer surface of the lifting shaft body 1 are provided with a thermal barrier coating 3.

[0030] The utility model improves the rotary lifting shaft used in a Czochralski single crystal furnace. The lifting shaft body is used to carry a graphite support rod, and drives a crucible containing silicon melt to move up and down under the action of a rotary lifting system. A thermal barrier coating is provided on the upper end and outer surface of the lifting shaft body. The thermal barrier coating plays a role of heat insulation, and prevents the graphite support rod from transferring the high heat of the crucible to the lifting shaft body, thereby preventing the lifting shaft body from cracking and failing due to thermal stress, and prolonging the service life of the lifting shaft body. In order to facilitate connection with a rotating magnetic fluid, the lower end of the lifting shaft body is also extended to form a connecting section, and the connecting section cooperates with the rotating magnetic fluid.

[0031] Furthermore, a tapered hole 4 is provided at the upper end of the lifting shaft body 1 in this embodiment, and the tapered hole 4 is used to be plugged in with the lower end of the graphite support rod, thereby improving the connection reliability between the lifting shaft body and the graphite support rod. At the same time, the inner wall of the tapered hole is also provided with a thermal barrier coating 3, which ensures the connection reliability while also ensuring the heat insulation capacity.

[0032] A cooling water channel hole 2 is provided on the lower end surface of the lifting shaft body 1. The cooling water channel hole is used to pass cooling water into the lifting shaft body to reduce the temperature of the lifting shaft body through heat exchange, thereby further avoiding the problem of cracking of the lifting shaft body due to thermal stress.

[0033] Furthermore, the end of the cooling water channel hole 2 located inside the lifting shaft 1 is spherical. Since the end of the cooling water channel hole is close to the heated end of the lifting shaft, the spherical design can avoid the existence of sharp corners in the cooling water channel hole, thereby avoiding the occurrence of concentrated areas of thermal stress and is also beneficial to extending the service life of the lifting shaft.

[0034] The thermal barrier coating 3 is an oxide coating, a nitride coating, a carbide coating or a boride coating.

[0035] The oxide coating is a zirconium oxide coating, a yttrium oxide coating, an aluminum oxide coating, or a tin oxide coating.

[0036] The nitride coating is a boron nitride coating, a silicon nitride coating or a titanium nitride coating.

[0037] The carbide coating is a titanium carbide coating.

[0038] The boride coating is a zirconium boride coating.

[0039] The thermal barrier coating adopts one of the above-mentioned oxide coating, nitride coating, carbide coating or boride coating.

[0040] The following is an introduction to the processing of thermal barrier coatings:

[0041] S1: Pre-treat the surface of the shaft to be sprayed, clean the oil and other debris on the surface with acetone and alcohol, and then sandblast the surface to be sprayed. The sandblasting pressure is 0.1-1MPa, and the sandblasting material is 30-100 mesh white jade corundum grains;

[0042] S2: Before spraying, the substrate surface is preheated with plasma flame flow to make the surface temperature reach 100-300°C, and the intermediate layer is sprayed with NiCrAlY metal powder with a thickness of 50-200μm;

[0043] S3: This embodiment uses zirconium oxide coating, using ZrO 2 -8wt%Y 2 O3 Nano-agglomerated zirconium oxide powder, spraying thickness is 100-800μm; spraying process parameters are set as current 300-800A, power 20-60KW, spray gun distance 50-120mm, gun speed 200-800mm / s, powder feeding rate 15-60g / min, main gas flow 30-50L / min.

[0044] After spraying, quality inspection is carried out to ensure that the appearance is continuous and complete, without cracks, splits and other defects. It can be used only after passing the inspection.

[0045] In summary, the utility model has the following beneficial effects:

[0046] The utility model improves the structure of the rotating lifting shaft, and the thermal barrier coating arranged effectively isolates the high temperature of the graphite support rod, thereby avoiding the problem of cracking of the rotating lifting shaft due to thermal stress, extending the service life after rotation and lifting, and reducing the later maintenance cost; further, the thermal barrier coating avoids the adhesion between the rotating lifting shaft and the graphite support rod, and can be easily removed for replacement, reducing the difficulty and maintenance cost of equipment maintenance; further, the thermal barrier coating effectively reduces the temperature difference between the high temperature and low temperature ends, thereby reducing the thermal stress of the rotating lifting shaft, avoiding crack failure inside the material, and also significantly reducing the temperature of the high temperature end of the rotating lifting shaft, effectively reducing the heat carried away by the circulating cooling water, and having a significant energy-saving effect.

[0047] Based on the described embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

Claims

1. The rotary lifting shaft of the rotary lifting system of the CZC single crystal furnace comprises a lifting shaft body, characterized in that: The upper end and outer surface of the lifting shaft body are provided with a thermal barrier coating, the upper end of the lifting shaft body is provided with a tapered hole, the inner wall of the tapered hole is also provided with a thermal barrier coating, and the lower end surface of the lifting shaft body is provided with a cooling water channel hole, and the end of the cooling water channel hole located inside the lifting shaft body is spherical.

2. The rotary lifting shaft of the rotary lifting system of the CZC single crystal furnace according to claim 1, characterized in that: The thermal barrier coating is an oxide coating, a nitride coating, a carbide coating or a boride coating.

3. The rotary lifting shaft of the rotary lifting system of the CZ single crystal pulling furnace according to claim 2, characterized in that: The oxide coating is a zirconium oxide coating, a yttrium oxide coating, an aluminum oxide coating, or a tin oxide coating.

4. The rotary lifting shaft of the rotary lifting system of the CZC single crystal furnace according to claim 2, characterized in that: The nitride coating is a boron nitride coating, a silicon nitride coating or a titanium nitride coating.

5. The rotary lifting shaft of the rotary lifting system of the CZ single crystal pulling furnace according to claim 2, characterized in that: The carbide coating is a titanium carbide coating.

6. The rotary lifting shaft of the rotary lifting system of the CZC single crystal furnace according to claim 2, characterized in that: The boride coating is a zirconium boride coating.

7. The rotary lifting shaft of the rotary lifting system of the CZ single crystal pulling furnace according to claim 2, characterized in that: The thickness of the thermal barrier coating is 100-800 μm.

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