A crystal growth visualisation monitoring system

Abstract

The utility model discloses a kind of crystal growth visual monitoring systems, belong to crystal growth technical field, for solving the technical problem that crystal growth process cannot be real-time visual monitoring. The visual monitoring system of the utility model, including visible light monitoring unit, X ray monitoring unit and crystal growth furnace;Visible light monitoring unit includes camera and visible light source;X ray monitoring unit includes X ray flat panel detector;Crystal growth furnace is symmetrically provided with observation window on both sides, camera and visible light source are oppositely arranged on both sides of crystal growth furnace and respectively align two observation windows. The visual monitoring system of the utility model can be real-time visual observation crystal macroscopic morphology and crystal growth microscopic interface, can greatly improve research and development efficiency.

Description

Technical Field

[0001] This utility model belongs to the field of crystal growth technology and relates to a crystal growth visualization monitoring system. Background Technology

[0002] The crucible lowering method is the most important method for preparing large-size single crystals. Scintillation crystals such as cesium iodide (CsI), sodium iodide (NaI), and lanthanum bromide (LaBr3) are all prepared using this method. However, during crystal growth using the crucible lowering method, the interface shape inside the crucible cannot be observed due to the shielding effect of the insulation layer and heating element. Therefore, it is impossible to adjust the growth conditions in real time according to the evolution of the crystallization interface. Currently, it is only possible to know whether a single crystal has been formed after the crystal growth is completed and the crystal is cooled and removed. Real-time monitoring of the growth process is not possible, which affects the cost and efficiency of crystal growth. Utility Model Content

[0003] Based on the above analysis, the present invention aims to provide a crystal growth visualization monitoring system to solve the technical problem that the crystal growth process cannot be visualized and monitored in real time.

[0004] The purpose of this utility model is mainly achieved through the following technical solutions.

[0005] This invention provides a crystal growth visualization monitoring system, including a visible light monitoring unit, an X-ray monitoring unit, and a crystal growth furnace; the visible light monitoring unit includes a camera and a visible light source; the X-ray monitoring unit includes an X-ray flat panel detector; observation windows are symmetrically arranged on both sides of the crystal growth furnace, and the camera and visible light source are arranged opposite each other on both sides of the crystal growth furnace and are respectively aligned with the two observation windows.

[0006] Furthermore, the observation window comprises double-layered hollow high-temperature resistant optical glass.

[0007] Furthermore, the visible light monitoring unit also includes a lifting rail, along which the camera can slide up and down.

[0008] Furthermore, the crystal growth furnace also includes a connection port, one end of which is connected to the quartz furnace tube inside the crystal growth furnace and the other end is connected to the inert gas tank and the vacuum pump.

[0009] Furthermore, the X-ray monitoring unit also includes a detector ground rail and an X-ray source ground rail, which are located on both sides of the crystal growth furnace, allowing the X-ray flat panel detector and the X-ray source to move in the vertical plane respectively.

[0010] Furthermore, the thickness of a single layer of double-layer hollow high-temperature resistant optical glass is 4-7mm.

[0011] Furthermore, the double-layered hollow high-temperature resistant optical glass is made of quartz or sapphire.

[0012] Furthermore, the direction of the beam emitted by the visible light source is perpendicular to the direction of the X-rays.

[0013] Furthermore, the crystal growth furnace includes multiple crucibles, and the direction of the beam emitted by the visible light source is parallel to the direction of the X-rays.

[0014] Furthermore, the crystal growth furnace also includes a crucible drive device, which can drive the crucible to rotate and descend.

[0015] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects: 1. The crystal growth visualization monitoring system of this utility model, by setting up a visible light monitoring unit and an observation window, can visualize and observe the macroscopic morphology of the crystal in real time, reflecting whether there are defects such as bubbles and cracks in the grown crystal; and combined with the X-ray monitoring unit for three-dimensional imaging monitoring of the crystal growth micro interface, it can effectively correlate the crystal micro growth interface with the crystal macroscopic morphology, establish the connection between growth conditions and interface in real time, achieve the goal of obtaining the ideal interface, and transform the crystal growth process from a "black box" to a visible and controllable one, greatly improving R&D efficiency.

[0016] 2. The crystal growth visualization monitoring system of this invention, by employing a flat panel detector, can acquire a complete two-dimensional projection image of the solid-liquid interface of crystal growth in the observation direction with a single exposure. Compared with the traditional linear array detector, which requires one-dimensional mechanical scanning to stitch together a two-dimensional image, this shortens the data acquisition time for a single projection, thereby significantly improving the overall efficiency of CT scanning. It achieves near real-time and dynamic monitoring of the crystal growth process. When the solid-liquid interface is not an ideal convex or flat interface, the crystal growth environment can be adjusted more promptly, reducing errors. Secondly, it avoids the vibration and misalignment problems caused by mechanical scanning of linear array detectors, reducing image artifacts at the source. Furthermore, the flat panel detector has higher detection efficiency and lower readout noise, and the reconstructed image has clearer details and more accurate grayscale information, improving the identification ability and measurement accuracy of the crystal growth interface.

[0017] 3. The crystal growth visualization monitoring system of this utility model uses a connection port to connect the quartz furnace tube to the inert gas tank and vacuum pump, which can protect the crystal growth process with an inert atmosphere, avoid the material from oxidation and moisture absorption in the high-temperature growth environment, and improve the crystal growth quality.

[0018] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objectives and other advantages of this invention can be realized and obtained through the embodiments described and the accompanying drawings, which are particularly pointed out. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the crystal growth visualization monitoring system according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the visible light monitoring unit and crystal growth furnace according to an embodiment of the present invention.

[0020] Figure label: 1-Visible light monitoring unit; 11-Camera; 12-Visible light source; 13-Lifting slide rail; 2 - X-ray monitoring unit; 21 - X-ray flat panel detector; 23 - Detector ground rail; 24 - X-ray source ground rail; 3-Crystal growth furnace; 31-Observation window; 32-Crucible; 33-Connection port; 4-Electrical control cabinet; 5-UPS power supply. Detailed Implementation

[0021] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0022] Example 1 This embodiment discloses a crystal growth visualization monitoring system, such as Figure 1 and Figure 2 As shown, it includes a visible light monitoring unit 1, an X-ray monitoring unit 2, and a crystal growth furnace 3; the visible light monitoring unit 1 includes a camera 11 and a visible light source 12; the X-ray monitoring unit 2 includes an X-ray flat panel detector 21; the crystal growth furnace 3 has observation windows 31 symmetrically arranged on both sides, and the camera 11 and the visible light source 12 are arranged opposite to each other on both sides of the crystal growth furnace 3 and are respectively aligned with the two observation windows 31.

[0023] The crystal growth visualization monitoring system of this embodiment is used to monitor the crystal growth process online when preparing large-size single crystals using the crucible lowering method, for example, the growth process of scintillation crystals such as cesium iodide (CsI), sodium iodide (NaI), and lanthanum bromide (LaBr3) using the Bridgman process. The crystal growth furnace 3 typically includes a quartz furnace tube, a heating module, an insulation layer, and a support system, and is surrounded by a furnace cover, a furnace cylinder, and a furnace bottom cover. The crystal growth crucible 32 is located inside the cavity of the quartz furnace tube, and the cavity is surrounded by the heating module, insulation layer, and furnace cylinder in sequence. An observation window 31 is opened on the furnace wall of the crystal growth furnace 3, located at the crystal growth position. A visible light source 12 illuminates the crystal from one side of the crystal towards the camera 11, while the camera 11, on the other side of the crystal, can clearly observe the crystallization and growth of the transparent crystal during the growth process. Preferably, the camera 11 is a high-definition camera. The X-ray monitoring unit 2 includes a CT three-dimensional imaging device, capable of monitoring the position and changes of the growth interface. Visible light monitoring unit 1, X-ray monitoring unit 2 and crystal growth furnace 3 are installed in a specific lead room (not shown in the figure). An electrical control cabinet 4 and a UPS power supply 5 are installed outside the lead room to facilitate the operation of the visible light monitoring unit 1, X-ray monitoring unit 2 and crystal growth furnace 3, and to adjust process parameters such as temperature gradient, descent speed and crucible rotation speed in a timely manner according to the monitored crystal growth status.

[0024] The crystal growth visualization monitoring system of this embodiment, by setting up a visible light monitoring unit 1 and an observation window 31, can observe the macroscopic morphology of the crystal in real time. It can reflect whether there are defects such as bubbles and cracks in the grown crystal, and promptly stop the growth process if the quality is obviously poor, reducing time costs. It solves the problem that the location and size of defects such as cracks cannot be observed during the growth of transparent crystals. At the same time, by setting up an X-ray monitoring unit 2 to monitor the three-dimensional imaging of the crystal growth micro-interface, it can effectively correlate the crystal micro-growth interface with the crystal macroscopic morphology, establish the connection between growth conditions and interface in real time, and achieve the goal of obtaining an ideal interface. This makes the crystal growth process a visible and controllable process, greatly improving R&D efficiency. In addition, by using an X-ray flat panel detector 21, A single exposure can acquire a complete two-dimensional projection image of the solid-liquid interface of crystal growth in the observation direction. Compared with the traditional linear array detector, which requires one-dimensional mechanical scanning to stitch together a two-dimensional image, this shortens the data acquisition time of a single projection, thus significantly improving the overall efficiency of CT scanning. It enables near real-time and dynamic monitoring of the crystal growth process. When the solid-liquid interface is not an ideal convex or flat interface, the crystal growth environment can be adjusted more promptly, reducing errors. It also avoids problems such as vibration and misalignment caused by mechanical scanning of linear array detectors, reducing image artifacts at the source. At the same time, the flat panel detector has higher detection efficiency and lower readout noise. The reconstructed image has clearer details and more accurate grayscale information, improving the identification ability and measurement accuracy of the crystal growth interface.

[0025] Considering the high-temperature environment inside the crystal growth furnace 3, the observation window 31 includes double-layered hollow high-temperature resistant optical glass to ensure good light transmittance and thermal stability while preventing the high temperature inside the furnace from spreading outwards. The inner layer of the double-layered hollow high-temperature resistant optical glass is close to the quartz furnace tube, while the outer layer is aligned with the outer surface of the furnace cylinder.

[0026] Optionally, the double-layer hollow high-temperature resistant optical glass can be made of quartz, sapphire, or other optical materials suitable for high-temperature applications, thereby providing better structural stability and good optical performance.

[0027] Preferably, the thickness of a single layer of the double-layer hollow high-temperature resistant optical glass is 4-7mm to enhance the heat preservation effect.

[0028] Considering that crystal growth is a continuous downward process, in order to achieve a comprehensive and clear observation of the grown crystal, such as... Figure 1 As shown, the visible light monitoring unit 1 also includes a lifting slide rail 13, and the camera 11 can slide up and down along the lifting slide rail 13 so as to dynamically follow the position changes of crystal growth, thereby obtaining reliable and accurate observation images.

[0029] Correspondingly, such as Figure 1 As shown, the X-ray monitoring unit 2 also includes a detector ground rail 23 and an X-ray source ground rail 24. The detector ground rail 23 and the X-ray source ground rail 24 are located on both sides of the crystal growth furnace 3, so that the X-ray flat panel detector 21 and the X-ray source can move in the vertical plane respectively, so that the positions of the X-ray flat panel detector 21 and the X-ray source correspond to the positions of the crystal growth interface.

[0030] In some embodiments, such as Figure 1 As shown, when a crucible is placed inside the crystal growth furnace 3, the direction of the beam emitted by the visible light source 12 is perpendicular to the direction of the X-ray, so that the camera 11, the visible light source 12, the X-ray flat panel detector 21 and the X-ray source can be installed on the four sides of the crystal growth furnace 3 respectively, thus providing sufficient space for the installation and observation of the visible light monitoring unit 1 and the X-ray monitoring unit 2, without interfering with each other.

[0031] The crystal growth furnace 3 also includes a crucible driving device, which can drive the crucible to rotate and descend. By driving the crucible 32 containing the melt and crystal to rotate around the axis, the sample is irradiated by an X-ray source during the rotation. Simultaneously, X-ray projection information passing through the crystal growth area at different angles is collected. Then, the multi-angle two-dimensional projection sequence is processed by a computer tomography image reconstruction algorithm to finally reconstruct a three-dimensional structural image reflecting the spatial distribution characteristics of the solid-liquid interface, thereby achieving the purpose of three-dimensional image monitoring of crystal growth.

[0032] To address the issue of materials easily oxidizing and absorbing moisture during high-temperature growth environments, such as... Figure 2 As shown, the crystal growth furnace 3 also includes a connection port 33. One end of the connection port 33 is connected to the quartz furnace tube inside the crystal growth furnace 3, and the other end is connected to an inert gas tank and a vacuum pump to ensure that the crystal growth process is protected by an inert atmosphere. Optionally, the inert gas is argon, nitrogen, or other suitable inert gas. The outer periphery of the observation window 31 is fixedly connected to the furnace body of the crystal growth furnace 3. It should be noted that the structures of the lifting slide rail 13, the ground rail, and the crucible drive device can all adopt existing technologies, and will not be described in detail here.

[0033] Example 2 The crystal growth visualization monitoring system in this embodiment differs from that in Embodiment 1 in that the direction of the beam emitted by the visible light source 12 is parallel to the direction of the X-rays.

[0034] When the crystal growth furnace 3 includes multiple crucibles 32, in order to avoid overlapping observation images between crystals in different crucibles 32, the camera 11 and the X-ray flat panel detector 21 are installed on the same side of the crystal growth furnace 3. The direction of the beam emitted by the visible light source 12 and the direction of the X-rays are both perpendicular to the arrangement direction of the crucibles 32, so that both the visible light monitoring unit 1 and the X-ray monitoring unit 2 can obtain observation images of crystal growth in each crucible 32.

[0035] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present utility model should be included within the protection scope of the present utility model.

Claims

1. A crystal growth visualization monitoring system, characterized in that, It includes a visible light monitoring unit (1), an X-ray monitoring unit (2), and a crystal growth furnace (3); The visible light monitoring unit (1) includes a camera (11) and a visible light source (12); The X-ray monitoring unit (2) includes an X-ray flat panel detector (21); The crystal growth furnace (3) has observation windows (31) symmetrically arranged on both sides. The camera (11) and the visible light source (12) are arranged opposite to each other on both sides of the crystal growth furnace (3) and are respectively aligned with the two observation windows (31).

2. The crystal growth visualization monitoring system according to claim 1, characterized in that, The observation window (31) comprises double-layered hollow high-temperature resistant optical glass.

3. The crystal growth visualization monitoring system according to claim 2, characterized in that, The visible light monitoring unit (1) also includes a lifting slide rail (13), and the camera (11) can slide up and down along the lifting slide rail (13).

4. The crystal growth visualization monitoring system according to claim 1, characterized in that, The crystal growth furnace (3) also includes a connection port (33), one end of which is connected to the quartz furnace tube inside the crystal growth furnace (3) and the other end is connected to the inert gas tank and the vacuum pump.

5. The crystal growth visualization monitoring system according to claim 1, characterized in that, The X-ray monitoring unit (2) also includes a detector ground rail (23) and an X-ray source ground rail (24). The detector ground rail (23) and the X-ray source ground rail (24) are located on both sides of the crystal growth furnace (3), so that the X-ray flat panel detector (21) and the X-ray source can move in the vertical plane respectively.

6. The crystal growth visualization monitoring system according to claim 2, characterized in that, The thickness of a single layer of the double-layer hollow high-temperature resistant optical glass is 4-7 mm.

7. The crystal growth visualization monitoring system according to claim 6, characterized in that, The double-layer hollow high-temperature resistant optical glass is made of quartz or sapphire.

8. The crystal growth visualization monitoring system according to any one of claims 1 to 7, characterized in that, The direction of the beam emitted by the visible light source (12) is perpendicular to the direction of the X-ray.

9. The crystal growth visualization monitoring system according to any one of claims 1 to 7, characterized in that, The crystal growth furnace (3) includes multiple crucibles, and the direction of the beam emitted by the visible light source (12) is parallel to the direction of the X-rays.

10. The crystal growth visualization monitoring system according to any one of claims 1 to 7, characterized in that, The crystal growth furnace (3) also includes a crucible driving device, which can drive the crucible to rotate and descend.

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