Hot wire framework and device and method for automatically controlling wire distance to deposit diamond

Abstract

The embodiment of the invention provides a hot wire framework and a device and method for automatically controlling wire distance to deposit diamond. The hot wire framework comprises a plurality of hot wires, a supporting assembly and at least one adjusting mechanism. The supporting assembly comprises a first metal rod, a second metal rod, a plurality of first metal blocks and a plurality of second metal blocks, the first metal rod and the second metal rod are oppositely arranged in the extending direction of the hot wire, the first metal blocks are arranged on the first metal rod in a sliding mode, the second metal blocks are arranged on the second metal rod in a sliding mode, one end of the hot wire is connected with the first metal blocks, and the other end of the hot wire is connected with the second metal blocks. The adjusting mechanism is connected with the first metal block and the second metal block so as to adjust the distance between the adjacent hot wires. The hot wire framework can solve the problem that the grain size is not uniform along with the increase of the deposition time and the thin film thickness.

Description

Technical Field

[0001] The present application relates to the technical field of hot wire chemical vapor deposition, and in particular to a hot wire architecture, a device and a method for automatically controlling wire distance to deposit diamond. Background Art

[0002] Hot Filament Chemical Vapor Deposition (HFCVD) is a process that uses a high-temperature hot wire (tungsten wire, tantalum wire) to cleave and excite the deposition gas into a large number of particles, which are then deposited on the substrate surface through a chemical reaction. Hot Filament Chemical Vapor Deposition is a technology used to prepare diamond films, which has the advantages of high deposition rate, high quality of deposited films and a wide range of applications. Therefore, the temperature of the hot wire and the surface temperature of the substrate are one of the keys to determining the diamond deposition rate and deposition quality. At present, in the process of preparing diamond films with hot filament chemical vapor deposition equipment, as the diamond film thickens, the distance between the hot wire and the film gradually decreases, the nucleation rate decreases, and the growth rate increases, resulting in the diamond film The grain size gradually increases with the increase of deposition time and film thickness, that is, the grain size at different positions of the same diamond film is different, which affects the quality of the diamond film. Summary of the invention

[0003] The purpose of the embodiment of the present application is to provide a hot wire structure, an apparatus and method for depositing diamonds with automatic control of wire distance, so as to solve the problem that the grain size gradually increases with the increase of deposition time and film thickness. The specific technical solution is as follows:

[0004] The first aspect of the present application provides a hot wire architecture, comprising: a plurality of hot wires; a supporting assembly, comprising a first metal rod and a second metal rod relatively arranged along the extension direction of the hot wires, and a plurality of first metal blocks slidably arranged on the first metal rod, and a plurality of second metal blocks slidably arranged on the second metal rod, one end of the hot wire is connected to the first metal block, and the other end of the hot wire is connected to the second metal block; at least one adjustment mechanism, the adjustment mechanism is connected to the first metal block and the second metal block to adjust the distance between adjacent hot wires.

[0005] In some embodiments, the hot wire structure includes two adjustment mechanisms, which are arranged at intervals along the extension direction of the hot wire and are respectively arranged on the outside of the first metal rod and the second metal rod, and the adjustment mechanisms are respectively connected to the first metal block and the second metal block.

[0006] In some embodiments, the adjustment mechanism includes: a driving assembly; a moving member, on which a plurality of slideways are provided, and one end of the moving member is connected to the driving assembly; a plurality of connecting members, which correspond one-to-one to the slideways, and one end of the connecting member is inserted into the slideway, and the other end of the connecting member is respectively connected to the first metal block or the second metal block; the driving assembly is used to drive the moving member to move in a first direction so that the moving member slides along the slideway relative to the connecting member, and can drive the connecting member to move in a second direction, thereby driving the hot wire to move in the second direction, wherein the first direction is parallel to the extension direction of the hot wire, and the second direction is coplanar and perpendicular to the first direction.

[0007] In some embodiments, the slideway penetrates or does not penetrate the moving member along a thickness direction of the moving member, and the thickness direction is perpendicular to the first direction and the second direction.

[0008] In some embodiments, the end of the slide away from the hot wire is the first end, and the end close to the hot wire is the second end. The first distances between adjacent slides at the first end are equal, and the second distances between adjacent slides at the second end are equal, and the second distance is greater than the first distance. Along the direction from the first end to the second end, the first distance gradually changes to the second distance.

[0009] In some embodiments, one of the slides located at the center or close to the center is recorded as a first slide, and the extension direction of the first slide is parallel to the first direction. The remaining slides located on both sides of the first slide are recorded as second slides, and the second slides are symmetrically distributed about the first slide. Along the direction away from the first slide, the angle between the second slide and the first direction increases successively.

[0010] In some embodiments, the second slide is a straight slide or a curved slide.

[0011] In some embodiments, the curved slide includes a first section and a second section, the first section is a straight section, and the second section is a curved section.

[0012] In some embodiments, the first metal rod, the second metal rod, the first metal block and the second metal block are made of the same material as the hot wire, and the first metal rod and the second metal rod are used to be electrically connected to the electrode assembly.

[0013] A second aspect of the present application provides a device for automatically controlling wire pitch for depositing diamond, comprising a deposition chamber, a control system, a temperature measurement system, an electrode assembly and at least one hot wire structure as described above; the hot wire and the support assembly are placed in the deposition chamber, and a portion of the adjustment mechanism is placed in the deposition chamber; the control system and the temperature measurement system are electrically connected, and the control system is electrically connected to the adjustment mechanism; a portion of the electrode assembly is placed in the deposition chamber and is electrically connected to the first metal rod and the second metal rod, respectively.

[0014] In some embodiments, the adjustment mechanism includes: a driving assembly; a moving member, a plurality of slideways are provided on the moving member, one end of the moving member is connected to the driving assembly; a plurality of connecting members, corresponding to the slideways one by one, and one end of the connecting member is inserted in the slideway, and the other end of the connecting member is respectively connected to the first metal block or the second metal block; the device for automatically controlling the wire pitch to deposit diamond includes: an upper cover; a workbench, the upper cover is covered on the workbench to form the deposition chamber; a mounting frame, fixed on the workbench, including a first bracket and a second bracket, the first metal rod is connected to the first bracket, the second metal rod is connected to the second bracket, the moving member is mounted on the mounting frame, and the driving assembly is located outside the deposition chamber.

[0015] The third aspect of the present application provides a method for automatically controlling wire pitch to deposit diamonds, using the above-mentioned device for automatically controlling wire pitch to deposit diamonds, comprising at least the following steps:

[0016] In the deposition chamber, a substrate is placed below the hot wire;

[0017] The initial spacing of the hot wires is adjusted to 4 mm to 10 mm by means of an adjustment mechanism;

[0018] The deposition chamber is evacuated, and hydrogen gas is introduced at a flow rate of 2000 ml / min-4000 ml / min until the pressure in the deposition chamber is constant;

[0019] The introduction of methane (CH 4 ), wherein the volume content of methane in the mixed gas of methane and hydrogen accounts for 2% to 5%, and the pressure in the deposition chamber is maintained at 6000Pa-8000Pa;

[0020] The electrode assembly is powered to heat the hot wire, and the temperature of the hot wire is controlled to be between 1500° C. and 2000° C. by a control system;

[0021] When the temperature of the hot wire rises to 1500°C-2000°C, the temperature measuring system detects the surface temperature of the substrate in real time and feeds back to the control system. When it meets the set temperature in the control system, the hydrogen flow rate is adjusted to 4000ml / min-8000ml / min to deposit diamond on the surface of the substrate;

[0022] The diamond deposition thickness increases continuously, the temperature measuring system detects the temperature of the diamond surface in real time, and feeds back to the control system, the control system compares the detected temperature of the diamond surface with the program set temperature, if the difference between the two exceeds the preset threshold, the control system controls the regulating mechanism to adjust the hot wire spacing, and detects the temperature of the diamond surface again through the temperature measuring system, until the difference between the detected diamond surface temperature and the program set temperature is within the preset threshold;

[0023] When the deposition time reaches the set value, the control system controls the temperature in the deposition chamber to drop to room temperature at a set rate.

[0024] The hot wire architecture, the device and method for automatically controlling the wire distance for depositing diamonds provided in the embodiments of the present application achieve the purpose of adjusting the distance between adjacent hot wires by setting an adjustment mechanism for adjusting the distance between adjacent first metal blocks and adjacent second metal blocks. In this way, as the thickness of the deposited diamond film increases, the distance between adjacent hot wires increases. By increasing the distance between adjacent hot wires, the temperature between adjacent hot wires can be reduced, thereby compensating for the excessively high surface temperature of the diamond film caused by the increase in the thickness of the diamond film, thereby maintaining a sufficient nucleation rate, reducing the crystal growth rate, and ensuring the uniformity of the grain size. In addition, as the distance between the hot wires increases, it is beneficial to reduce the radiant heat between adjacent hot wires, reduce the temperature of the hot wires, reduce the risk of carbonization of the hot wire surface, and further reduce the risk of hot wire adhesion or even breakage.

[0025] Of course, implementing any product or method of the present application does not necessarily require achieving all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other embodiments can also be obtained based on these drawings.

[0027] Figure 1 A simplified schematic diagram of the structure of a device for automatically controlling wire pitch for depositing diamond provided in an embodiment of the present application;

[0028] Figure 2A schematic diagram of a partial structure of a device for automatically controlling wire pitch for depositing diamonds provided in an embodiment of the present application;

[0029] Figure 3 A top view of a hot wire structure provided in an embodiment of the present application in one embodiment;

[0030] Figure 4 A bottom view of a hot wire structure provided in an embodiment of the present application in one embodiment;

[0031] Figure 5 A schematic diagram of the structure of a moving part of the system of an embodiment of the present application in one embodiment;

[0032] Figure 6 This is a schematic diagram of the structure of the moving parts and the dynamic parts of the system of the embodiment of the present application in one embodiment.

[0033] Reference numerals:

[0034] Hot wire structure 100; hot wire 110; support assembly 120; first metal rod 121; second metal rod 122; first metal block 123; second metal block 124; adjustment mechanism 130; moving part 131; slide 1311; first end 1311a; second end 1311b; first slide 13111; second slide 13112; first section 131121; second section 131122; connecting part 132; driving assembly 133; control system 200; temperature measurement system 300; deposition chamber 400; upper cover 410; workbench 420; electrode assembly 500; first electrode 510; second electrode 520; jet pipeline 600; jet hole 610; gas source 700; substrate 800; first distance L1; second distance L2. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field based on this application belong to the scope of protection of the present invention.

[0036] In the process of preparing diamond film using hot wire chemical vapor deposition, as the thickness of the diamond film increases, the distance between the surface of the diamond film and the hot wire 110 gradually decreases, the surface temperature of the diamond increases, and the supercooling decreases, which reduces the nucleation rate, increases the growth rate, and gradually increases the grain size, resulting in different grain sizes at different thickness positions of the final diamond film, which seriously affects the quality of the diamond film.

[0037] In order to solve the above technical problems, Figure 1, Figure 2 As shown, the embodiment of the present application provides a hot wire architecture 100, which includes: a plurality of hot wires 110, a support assembly 120 and at least one adjustment mechanism 130. The support assembly 120 includes a first metal rod 121 and a second metal rod 122 arranged relatively along the extension direction of the hot wire 110, and a plurality of first metal blocks 123 slidably arranged on the first metal rod 121, and a plurality of second metal blocks 124 slidably arranged on the second metal rod 122. One end of the hot wire 110 is connected to the first metal block 123, and the other end of the hot wire 110 is connected to the second metal block 124. The adjustment mechanism 130 is connected to the first metal block 123 and the second metal block 124 to adjust the distance between adjacent hot wires 110.

[0038] In the embodiment of the present application, an adjustment mechanism 130 is provided to adjust the distance between adjacent first metal blocks 123 and adjacent second metal blocks 124, so as to achieve the purpose of adjusting the distance between adjacent hot wires 110. In this way, as the thickness of the diamond film deposition increases, the distance between adjacent hot wires 110 increases. By increasing the distance between adjacent hot wires 110, the temperature between adjacent hot wires 110 can be reduced, thereby compensating for the excessively high surface temperature of the diamond film caused by the increase in the thickness of the diamond film, thereby maintaining a sufficient nucleation rate, reducing the crystal growth rate, and ensuring the uniformity of the grain size. In addition, as the distance between the hot wires 110 increases, it is beneficial to reduce the radiant heat between adjacent hot wires 110, reduce the temperature of the hot wire 110, reduce the risk of carbonization of the surface of the hot wire 110, and further reduce the risk of adhesion or even breakage of the hot wire 110.

[0039] The support component 120 is made of metal, so it can be electrically connected to the metal rod through the electrode to achieve electrical connection with the hot wire 110. In this way, the support component 120 can play both a supporting role and an electrical connection role, which is conducive to simplifying the structure of the hot wire architecture 100.

[0040] Optionally, the hot wires 110 are arranged parallel to each other.

[0041] In some embodiments of the present application, the adjustment mechanism 130 may include one, and the positions of the first metal block 123 and the second metal block 124 are adjusted by the same adjustment mechanism 130. Driven by the first metal block 123 and the second metal block 124, the distance between the hot wires 110 can be adjusted.

[0042] In some embodiments of the present application, Figure 1 , Figure 2As shown, the hot wire structure 100 includes two adjustment mechanisms 130, which are arranged at intervals along the extension direction of the hot wire 110 and are respectively arranged on the outside of the first metal rod 121 and the second metal rod 122. The adjustment mechanisms 130 are respectively connected to the first metal block 123 and the second metal block 124.

[0043] In this embodiment, the adjustment mechanism 130 is respectively arranged on the outer side of the first metal rod 121 and the second metal rod 122, where the outer side can be understood as: along the extension direction of the hot wire 110, the first metal rod 121 and the second metal rod 122 are away from the hot wire 110. Each adjustment mechanism 130 is used to adjust the position of the nearest metal block. Providing two adjustment mechanisms 130 can simplify the structure of the adjustment mechanism 130.

[0044] In some embodiments of the present application, Figure 1 , Figure 3 and Figure 4 As shown, the adjustment mechanism 130 includes: a driving assembly 133, a moving member 131 and a plurality of connecting members 132. The moving member 131 is provided with a plurality of slideways 1311, and one end of the moving member 131 is connected to the driving assembly 133. The plurality of connecting members 132 correspond to the slideways 1311 one by one, and one end of the connecting member 132 is inserted into the slideway 1311, and the other end of the connecting member 132 is respectively connected to the first metal block 123 or the second metal block 124. The driving assembly 133 is used to drive the moving member 131 to move along a first direction, so that the moving member 131 slides along the slideway 1311 relative to the connecting member 132, and can drive the connecting member 132 to move along a second direction, thereby driving the hot wire 110 to move along the second direction, wherein the first direction is parallel to the extension direction of the hot wire 110, and the second direction is coplanar and perpendicular to the first direction.

[0045] In this embodiment, the driving assembly 133 is used to drive the moving member 131 to move in a first direction, that is, the extension direction of the hot wire 110. Since one end of the connecting member 132 is inserted in the slideway 1311 of the moving member 131, when the moving member 131 slides relative to the slideway 1311, the one end inserted in the slideway 1311 can move in a second direction according to the change in the shape of the slideway 1311, that is, move horizontally perpendicular to the extension direction of the hot wire 110. In this way, the metal block connected to the connecting member 132 will also move horizontally under the action of the connecting member 132, thereby achieving the purpose of changing the distance between adjacent hot wires 110.

[0046] It should be noted that when there is only one adjustment mechanism 130, the connector 132 needs to connect the first metal block 123 and the second metal block 124 at the same time. The connector 132 can be a special-shaped structure to avoid the position corresponding to the hot wire 110 and reduce the impact on the temperature field around the hot wire 110. For example, the hot wire 110 includes a first horizontal section, the first horizontal section is connected to the first metal block 123, the end of the first horizontal section is connected to the first vertical section, the second horizontal section, and the second vertical section in sequence, the end of the second vertical section is connected to the second metal block 124, and the length of the second horizontal section is substantially equal to the length of the hot wire 110. Of course, a third horizontal section can also be set at the end of the second vertical section, and the third horizontal section is used to connect to the second metal block 124.

[0047] Optionally, the driving assembly 133 may be a lead screw motor, or a combination of a motor and a transmission assembly, such as a combination of a motor and a synchronous belt, a combination of a motor and a gear rack, etc. Taking the lead screw motor as an example, the moving member 131 is connected to the nut of the lead screw motor, and when the screw of the lead screw motor rotates forward or reversely, the nut is driven to move in a direction away from the first metal rod 121 or the second metal rod 122, or in a direction close to the first metal rod 121 or the second metal rod 122, so that the hot wires 110 are moved closer to or away from each other.

[0048] The slideway 1311 may or may not penetrate the moving member 131 along the thickness direction of the moving member 131 , and the thickness direction is perpendicular to the first direction and the second direction.

[0049] When the slide 1311 penetrates the moving part 131 along the thickness direction of the moving part 131, that is, the slide 1311 is a through-hole type slide 1311, the connecting part 132 can be inserted deeper, thereby improving the connection reliability between the connecting part 132 and the moving part 131. In addition, the bottoms of the connecting part 132 and the moving part 131 do not contact each other during the relative sliding process, thereby reducing the sliding friction.

[0050] When the slideway 1311 does not penetrate the moving member 131 along the thickness direction of the moving member 131, that is, the slideway 1311 is a groove type slideway 1311. The slideway 1311 does not penetrate the moving member 131, which is beneficial to improving the continuous strength of the moving member 131 and extending the service life of the moving member 131.

[0051] In order to change the distance between adjacent hot wires 110, the slideway 1311 on the moving member 131 satisfies the following conditions: the end of the slideway 1311 away from the hot wire 110 is the first end 1311a, the end close to the hot wire 110 is the second end 1311b, the first distance L1 between adjacent slideways 1311 at the first end 1311a is equal, the second distance L2 between adjacent slideways 1311 at the second end 1311b is equal, and the second distance L2 is greater than the first distance L1, and the first distance L1 gradually changes to the second distance L2 along the direction from the first end 1311a to the second end 1311b, as shown in FIG. Figure 5 , Figure 6 shown.

[0052] It should be noted that when the distance between the first ends 1311a of two adjacent slideways 1311 is the first distance L1, the initial position of the connecting member 132 is located at the first end 1311a, and the moving member 131 moves in a direction away from the hot wire 110. Of course, the second distance L2 can also be smaller than the first distance L1, so that the initial position of the connecting member 132 is located at the second end 1311b, and the moving member 131 moves in a direction close to the hot wire 110. Both of the above methods are within the protection scope of the present application.

[0053] The second distance L2 is greater than the first distance L1 as an example for explanation. Figure 5 , Figure 6 As shown, when the movable member 131 moves relative to the connecting member 132 from being close to the hot wire 110 to being away from the hot wire 110, the connecting member 132 moves from the first end 1311a of the slide 1311 to the second end 1311b. Since the distance of the slide 1311 at the second end 1311b is greater than the distance at the first end 1311a, when the connecting member 132 moves to the second end 1311b, the distance between adjacent connecting members 132 increases, and the distance between the adjacent first metal block 123 and the adjacent second metal block 124 connected to the connecting member 132 naturally increases, thereby the distance between the adjacent hot wires 110 connected to the first metal block 123 and the second metal block 124 also increases.

[0054] As a feasible embodiment, Figure 5 , Figure 6 As shown, one of the slides 1311 located at the center or close to the center is recorded as the first slide 13111, and the extension direction of the first slide 13111 is parallel to the first direction. The remaining slides 13111 located on both sides of the first slide 13111 are recorded as second slides 13112, and the second slides 13112 are symmetrically distributed about the first slide 13111, and the angles between the second slides 13112 and the first direction increase successively in the direction away from the first slide 13111.

[0055] The number of slideways 1311 can be an odd number or an even number. When it is an odd number, Figure 6 As shown, the first slideway 13111 is the slideway 1311 located in the center. Figure 5 As shown, the first slideway 13111 is one of the slideways 1311 close to the center. The remaining slideways 1311 located on both sides of the first slideway 13111 are second slideways 13112, and the second slideways 13112 are symmetrically distributed about the first slideway 13111. Along the direction away from the first slideway 13111, the angle between the second slideway 13112 and the first direction increases successively, which means that the further away from the first slideway 13111, the greater the angle between the second slideway 13112 and the first direction, so as to ensure that the distance between adjacent hot wires 110 is increased after adjustment by the adjustment mechanism 130, and the increased distance is equal.

[0056] Alternatively, if Figure 5 , Figure 6 As shown, the second slide 13112 can be a straight slide or a curved slide.

[0057] The second slide 13112 is a linear slide, which has the advantage of a simple structure. The angle between the second slide 13112 and the first direction is an acute angle, and the range of variation can be 15°-60°. If the angle is too small, for example, less than 15°, the change in the distance between the hot wires 110 is small, the impact on the surrounding temperature field is small, and the impact on the grain size is also small. If the angle is too large, for example, greater than 60°, the relative sliding between the moving part 131 and the connecting part 132 is more difficult due to the large change in angle during relative sliding, which is easy to cause wear between the two.

[0058] Of course, the slideway 1311 may also be a curved slideway, which makes the relative sliding between the moving member 131 and the connecting member 132 smoother, and can reasonably utilize the arrangement space of the moving member 131, so that more slideways 1311 can be arranged in the same arrangement space.

[0059] The curved slideway can be an arc slideway with a constant radius of curvature, or a curved slideway with an inflection point. For example, the shape of the slideway 1311 can be related to the function Y=X 3 The geometric image on [0, +∞] is similar to or can be compared to the function Y=X 3 The geometric image on [-∞, 0] is similar.

[0060] Of course, the curved slide can also be set up in sections, such as Figure 6 As shown, the curved slide includes a first section 131121 and a second section 131122, the first section 131121 is a straight section, and the second section 131122 is a curved section.

[0061] In some embodiments of the present application, the first metal rod 121 , the second metal rod 122 , the first metal block 123 , and the second metal block 124 are made of the same material as the hot wire 110 , and the first metal rod 121 and the second metal rod 122 are used to be electrically connected to the electrode assembly 500 .

[0062] The electrode assembly 500 includes a first electrode 510 and a second electrode 520, wherein the first electrode 510 can be a positive electrode or a negative electrode, and the second electrode 520 can be a negative electrode or a positive electrode. The first metal rod 121 is electrically connected to the first electrode 510, and the second metal rod 122 is electrically connected to the second electrode 520, so that the two ends of the hot wire 110 are electrically connected to the positive electrode and the negative electrode respectively. The first metal rod 121, the second metal rod 122, the first metal block 123 and the second metal block 124 are made of the same material as the hot wire 110, so the contact resistance between the first metal rod 121 and the first metal block 123, the first metal block 123 and the hot wire 110, and the contact resistance between the second metal rod 122 and the second metal block 124, and the second metal block 124 and the hot wire 110 can be reduced. This is because the resistivity of the same material is lower, and the contact resistance will also be reduced accordingly. In addition, the contact surfaces of the same material are easier to achieve close contact, which reduces the generation of contact resistance and is conducive to improving the utilization rate of electric energy. ‌

[0063] Optionally, the hot wire 110 may be a tantalum wire. Metal tantalum has an extremely high melting point, which can reach 2996°C, which enables the tantalum wire to maintain stable performance in a high temperature environment and is not easy to melt or deform. Of course, in some embodiments, the hot wire 110 may also be made of tungsten wire, molybdenum wire, etc., which are all suitable for the hot wire architecture 100 provided in the embodiments of the present application.

[0064] Of course, the first metal rod 121, the second metal rod 122, the first metal block 123, the second metal block 124 and the hot wire 110 may also be made of similar materials. The similar materials of the metal rods, metal blocks and the hot wire 110 are also conducive to reducing the contact resistance between them.

[0065] A second aspect of the present application provides a device for automatically controlling wire pitch for depositing diamonds, such as Figure 1 , Figure 2As shown, the device for automatically controlling wire pitch for depositing diamond includes a deposition chamber 400, a control system 200, a temperature measurement system 300, at least two electrode assemblies 500 and at least one hot wire structure 100 as described above; the hot wire 110 and the support assembly 120 are placed in the deposition chamber 400, and a part of the adjustment mechanism 130 is placed in the deposition chamber 400; the control system 200 and the temperature measurement system 300 are electrically connected, and the control system 200 is electrically connected to the adjustment mechanism 130; a part of the electrode assembly 500 is placed in the deposition chamber 400, and is respectively connected to the first metal rod 121 and the second metal rod 122.

[0066] The deposition chamber 400 is a reaction chamber for depositing a diamond film. The deposition chamber 400 is a closed cavity that can maintain the reaction gas atmosphere in the deposition chamber 400. Placing the hot wire 110 in the deposition chamber 400 can ensure the stability of the temperature field around the hot wire 110. During the deposition process, the change in the deposition thickness will cause the change in the superheat of the surface of the deposited film. The temperature of the surface of the deposited film is fed back in real time by the temperature measurement system 300. The control system 200 controls the adjustment mechanism 130 to adjust the distance between adjacent hot wires 110 according to the information fed back by the temperature measurement system 300, so as to reduce the superheat of the surface of the diamond film caused by the reduction in the distance between the surface of the diamond film and the hot wire 110, thereby ensuring the nucleation rate of the surface of the diamond film and reducing the growth rate of the crystal, so that the grain size is basically consistent with the grain size that has been formed, so that the grain size of the deposited diamond film is uniform, and the quality of the diamond film is improved. In addition, the distance between the hot wires 110 is adjusted by the adjustment mechanism 130 so that as the thickness of the diamond film deposition increases, the distance between the hot wires 110 also increases, which is beneficial to reducing the radiant heat between adjacent hot wires 110 and lowering the temperature of the hot wires 110, thereby reducing the risk of carbonization of the surface of the hot wires 110, and further reducing the risk of adhesion or even breakage of the hot wires 110, which is beneficial to extending the service life of the hot wire architecture 100.

[0067] The temperature measurement system 300 may be an infrared temperature measurement system 300. The infrared temperature measurement system 300 does not need to contact the surface of the substrate 800 or the surface of the diamond film. The installation position is flexible and it is convenient to measure the temperature of the substrate 800 or the surface of the diamond film. The substrate 800 is a carrier for depositing the diamond film and can be selected from Si, graphite, Mo, W, SiO 2 , tungsten carbide, silicon carbide, Si 3 N 4 For example, the substrate 800 is a Mo sheet.

[0068] In some embodiments of the present application, the device for automatically controlling the wire pitch for depositing diamond comprises: an upper cover 410, a workbench 420 and a mounting frame. The upper cover 410 covers the workbench 420 to form a deposition chamber 400. The mounting frame is fixed on the workbench 420, and the mounting frame comprises a first bracket and a second bracket, a first metal rod 121 is connected to the first bracket, a second metal rod 122 is connected to the second bracket, a moving member 131 is mounted on the mounting frame, and a driving assembly 133 is located outside the deposition chamber 400.

[0069] The upper cover 410 is covered on the workbench 420 to form a closed deposition chamber 400. During the deposition process, the deposition chamber 400 is in a reaction gas atmosphere to prevent air from entering, avoid oxidation of the hot wire 110 and the substrate 800 surface, and ensure the smooth progress of the deposition process. The moving part 131 is fixed on the workbench 420 by a mounting frame, wherein the mounting frame can be made of a high-temperature resistant insulating material. The driving assembly 133 is placed outside the deposition chamber 400, so that the driving assembly 133 does not need to be designed as a high-temperature resistant component, and the manufacturing cost of the device for automatically controlling the wire pitch deposition diamond can be reduced. One end of the moving part 131 can be connected to the driving assembly 133 by means of an intermediate connecting piece 132, and the middle piece connecting piece 132 passes through the side wall of the upper cover 410 and is connected to the driving assembly 133.

[0070] It can be understood that the device for automatically controlling the wire pitch for depositing diamond includes an air jet pipeline 600, which can extend from the top of the upper cover 410 into the deposition chamber 400, and has an air jet hole 610 on the side close to the hot wire 110. The gas in the air jet pipeline 600 is ejected toward the hot wire 110 through the air jet hole 610. One end of the air jet pipeline 600 is connected to the gas source 700, and the gas is cleaved and excited after passing through the surface of the hot wire 110. Taking the deposition of diamond film as an example, the gas source 700 is a carbon source and a hydrogen source gas, and the gas passing through the hot wire 110 is decomposed into active carbon atom groups and hydrogen ions. The decomposed active carbon atom groups and hydrogen ions reach the surface of the substrate 800 set on the workbench 420 just below the hot wire 110. By controlling the internal air pressure, temperature and hydrogen ion concentration of the deposition chamber 400, the diamond particles are reorganized and nucleated on the surface of the substrate 800, and then grow into a diamond film or thick film. The device for automatically controlling the wire pitch to deposit diamond also includes a vacuum pumping device for evacuating the deposition chamber 400 to ensure a vacuum atmosphere in the deposition chamber 400.

[0071] A third aspect of the embodiments of the present application provides a method for automatically controlling wire pitch to deposit diamonds, using the above-mentioned device for automatically controlling wire pitch to deposit diamonds, comprising at least the following steps:

[0072] S1: In the deposition chamber 400 , the substrate 800 is placed below the hot wire 110 .

[0073] S2: The initial spacing of the hot wires 110 is adjusted to 4 mm-10 mm through the adjustment mechanism 130 .

[0074] S3: Evacuate the deposition chamber 400 and introduce hydrogen at a flow rate of 2000ml / min-4000ml / min until the pressure in the deposition chamber 400 is constant.

[0075] S4: Introduce methane CH 4 , wherein the volume content of methane in the mixed gas of methane and hydrogen accounts for 2%~5%, and the pressure in the deposition chamber 400 is maintained at 6000Pa-8000Pa.

[0076] S5: Power on the electrode assembly 500 to heat the hot wire 110, and control the temperature of the hot wire 110 to be between 1500°C and 2000°C through the control system 200.

[0077] S6: When the temperature of the hot wire 110 rises to 1500℃-2000℃, the temperature measurement system 300 detects the surface temperature of the substrate 800 in real time and feeds back to the control system 200. When it meets the set temperature in the control system 200, such as 800℃-1200℃, the hydrogen flow rate is adjusted to 4000ml / min-8000ml / min, and diamond is deposited on the surface of the substrate 800.

[0078] S7: The thickness of diamond deposition increases continuously, and the temperature measuring system 300 detects the temperature of the diamond surface in real time and feeds back to the control system 200. The control system 200 compares the detected temperature of the diamond surface with the program set temperature. If the difference between the two exceeds a preset threshold, such as 50°C, the control system 200 controls the adjustment mechanism 130 to adjust the spacing of the hot wires 110, and detects the temperature of the diamond surface again through the temperature measuring system 300 until the difference between the detected diamond surface temperature and the program set temperature is within the preset threshold.

[0079] S8: When the deposition time reaches a set value, for example, 150 hours to 200 hours, the control system 200 controls the temperature in the deposition chamber 400 to drop to room temperature at a set rate.

[0080] The temperature measuring system 300 detects the surface temperature of the deposited diamond film in real time, and compares the detected surface temperature with the program setting temperature. When the difference between the two exceeds the preset threshold, such as 50°C, the control system 200 will control the adjustment mechanism 130 to work and adjust the spacing of the hot wires 110. Since the diamond film is getting closer and closer to the hot wires 110, the temperature of the diamond surface is generally higher than the program setting temperature. Therefore, the distance between the hot wires 110 can be increased by the adjustment mechanism 130, thereby achieving the purpose of reducing the surface temperature of the diamond. That is to say, the initial spacing of the hot wires 110 during the deposition process is the minimum value, that is, the connecting member 132 is at the first end 1311a of the slideway 1311, so that the adjustment mechanism 130 has a larger adjustment space for the spacing of the hot wires 110 during the deposition process. Of course, according to actual conditions, the initial spacing of the hot wires 110 can also be an intermediate value, that is, the connecting member 132 is at the middle position of the slideway 1311, so that the spacing of the hot wires 110 can be increased or reduced by the adjustment mechanism 130. Since this method can control the surface temperature of the substrate 800 and the surface temperature of the diamond to always be within the programmed temperature range, it can ensure that the grain size of the deposited diamond film is uniform, thereby improving the quality of the diamond film.

[0081] It should be noted that step S2 can be performed before S1, or after S1, after S3 or even after S4, and this application does not limit this.

[0082] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0083] Each embodiment in this specification is described in a related manner, and the same or similar parts between the embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

[0084] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A hot wire structure, characterized in that: include: a plurality of hot wires (110); A support assembly (120), comprising a first metal rod (121) and a second metal rod (122) arranged opposite to each other along an extension direction of the hot wire (110), and a plurality of first metal blocks (123) slidably arranged on the first metal rod (121), and a plurality of second metal blocks (124) slidably arranged on the second metal rod (122), one end of the hot wire (110) being connected to the first metal block (123), and the other end of the hot wire (110) being connected to the second metal block (124); At least one adjustment mechanism (130), the adjustment mechanism (130) being connected to the first metal block (123) and the second metal block (124) to adjust the distance between adjacent hot wires (110).

2. The hot wire structure according to claim 1, characterized in that: The hot wire structure (100) comprises two adjustment mechanisms (130) which are arranged at intervals along the extension direction of the hot wire (110) and are respectively arranged on the outside of the first metal rod (121) and the second metal rod (122); the adjustment mechanisms (130) are respectively connected to the first metal block (123) and the second metal block (124).

3. The hot wire structure according to claim 2, characterized in that: The adjustment mechanism (130) comprises: Drive assembly (133); A moving member (131), wherein a plurality of slideways (1311) are provided on the moving member (131), and one end of the moving member (131) is connected to the driving assembly (133); a plurality of connecting members (132) corresponding one to the slideway (1311), one end of each connecting member (132) being inserted into the slideway (1311), and the other end of each connecting member (132) being connected to the first metal block (123) or the second metal block (124); The driving assembly (133) is used to drive the moving member (131) to move along a first direction, so that the moving member (131) slides along the slideway (1311) relative to the connecting member (132), and is capable of driving the connecting member (132) to move along a second direction, thereby driving the hot wire (110) to move along the second direction, wherein the first direction is parallel to the extension direction of the hot wire (110), and the second direction is coplanar with and perpendicular to the first direction.

4. The hot wire structure according to claim 3, characterized in that: The slideway (1311) passes through or does not pass through the moving member (131) along a thickness direction of the moving member (131), and the thickness direction is perpendicular to the first direction and the second direction.

5. The hot wire structure according to claim 3, characterized in that: The end of the slideway (1311) away from the hot wire (110) is the first end (1311a), and the end close to the hot wire (110) is the second end (1311b); the first distances (L1) between adjacent slideways (1311) at the first end (1311a) are equal, and the second distances (L2) between adjacent slideways (1311) at the second end (1311b) are equal, and the second distance (L2) is greater than the first distance (L1); and along the direction from the first end (1311a) to the second end (1311b), the first distance (L1) gradually changes toward the second distance (L2).

6. The hot wire structure according to claim 5, characterized in that: One of the slides (1311) located at the center or close to the center is recorded as a first slide (13111), the extension direction of the first slide (13111) is parallel to the first direction, and the remaining slides (13111) located on both sides of the first slide (13111) are recorded as second slides (13112), the second slides (13112) are symmetrically distributed about the first slide (13111), and the angle between the second slide (13112) and the first direction increases successively along the direction away from the first slide (13111).

7. The hot wire structure according to claim 6, characterized in that: The second slide (13112) is a straight slide or a curved slide.

8. The hot wire structure according to claim 6, characterized in that: The curved slide comprises a first section (131121) and a second section (131122), wherein the first section (131121) is a straight section, and the second section (131122) is a curved section.

9. The hot wire structure according to claim 3, characterized in that: The first metal rod (121), the second metal rod (122), the first metal block (123) and the second metal block (124) are made of the same material as the hot wire (110); the first metal rod (121) and the second metal rod (122) are used to be electrically connected to the electrode assembly (500).

10. A device for automatically controlling wire pitch to deposit diamond, characterized in that: It comprises a deposition chamber (400), a control system (200), a temperature measurement system (300), an electrode assembly (500), and at least one hot wire structure (100) as claimed in any one of claims 1 to 9; The hot wire (110) and the support assembly (120) are placed in the deposition chamber (400), and a portion of the adjustment mechanism (130) is placed in the deposition chamber (400); The control system (200) is electrically connected to the temperature measurement system (300), and the control system (200) is electrically connected to the adjustment mechanism (130); A portion of the electrode assembly (500) is placed in the deposition chamber (400) and is electrically connected to the first metal rod (121) and the second metal rod (122), respectively.

11. The device for automatically controlling wire pitch for depositing diamond according to claim 10, characterized in that: The adjustment mechanism (130) comprises: Drive assembly (133); A moving member (131), wherein a plurality of slideways (1311) are provided on the moving member (131), and one end of the moving member (131) is connected to the driving assembly (133); a plurality of connecting members (132) corresponding one to the slideway (1311), one end of each connecting member (132) being inserted into the slideway (1311), and the other end of each connecting member (132) being connected to the first metal block (123) or the second metal block (124); The device for automatically controlling wire spacing to deposit diamonds comprises: Upper cover (410); A workbench (420), wherein the upper cover (410) covers the workbench (420) to form the deposition chamber (400); The mounting frame is fixed on the workbench (420), and includes a first bracket and a second bracket. The first metal rod (121) is connected to the first bracket, and the second metal rod (122) is connected to the second bracket. The moving part (131) is mounted on the mounting frame, and the driving component (133) is located outside the deposition chamber (400).

12. A method for automatically controlling wire pitch to deposit diamond, characterized in that: The device for automatically controlling wire distance for depositing diamond using any one of claims 10 or 11 comprises at least the following steps: In the deposition chamber (400), a substrate (800) is placed below the hot wire (110); The initial spacing of the hot wires (110) is adjusted to 4 mm-10 mm by means of an adjustment mechanism (130); The deposition chamber (400) is evacuated, and hydrogen gas is introduced at a flow rate of 2000 ml / min-4000 ml / min until the pressure in the deposition chamber (400) is constant; Passing methane (CH4), wherein the volume content of methane in the mixed gas of methane and hydrogen is 2% to 5%, and maintaining the pressure in the deposition chamber (400) at 6000Pa to 8000Pa; Powering the electrode assembly (500) to heat the hot wire (110), and controlling the temperature of the hot wire (110) to be between 1500° C. and 2000° C. through a control system (200); When the temperature of the hot wire (110) rises to 1500°C-2000°C, the temperature measuring system (300) detects the surface temperature of the substrate (800) in real time and feeds back to the control system (200); when the temperature meets the set temperature in the control system (200), the hydrogen flow rate is adjusted to 4000ml / min-8000ml / min, and diamond is deposited on the surface of the substrate (800); The diamond deposition thickness continues to increase, the temperature measurement system (300) detects the temperature of the diamond surface in real time, and feeds back to the control system (200), the control system (200) compares the detected diamond surface temperature with the program set temperature, and if the difference between the two exceeds a preset threshold, the control system (200) controls the adjustment mechanism (130) to adjust the spacing of the hot wires (110), and detects the diamond surface temperature again through the temperature measurement system (300), until it is detected that the difference between the diamond surface temperature and the program set temperature is within the preset threshold; When the deposition time reaches a set value, the control system (200) controls the temperature in the deposition chamber (400) to drop to room temperature at a set rate.

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