Diamond substrate, processing method of diamond substrate, diamond load and preparation method of diamond load

Abstract

The invention relates to a diamond substrate and a processing method thereof, and a diamond load and a manufacturing method thereof, and the processing method of the diamond substrate comprises the following steps: providing a diamond sheet with a first surface and a second surface which are opposite to each other; a laser cutting method is adopted for forming a through groove in a predefined shape in the diamond sheet, the through groove penetrates through the diamond sheet from the first face to the second face, and a grooved substrate is obtained; and a carborundum grinding tool is adopted to extend into the through groove, so that at least one grinding surface of the carborundum grinding tool is in close contact with the side wall of the through groove, the side wall of the through groove is ground, and the diamond substrate is obtained. The graphite slag attached to the side wall of the diamond through groove can be efficiently removed, the process is simple and convenient, use is easy, the cost is low, popularization is easy, then the adhesive force of a diamond side face film layer can be effectively improved, and the stability of a rear-end product (such as a diamond load) is improved; the production is not limited by environmental evaluation, the universality is high, and the economic value and the popularization value are very good.

Description

Technical Field

[0001] The present application relates to the technical field of diamond-based thin film circuits, and in particular to a diamond substrate and a processing method thereof, a diamond load and a preparation method thereof. Background Art

[0002] Diamond is the best material for making high-power, high-frequency RF devices due to its low dielectric constant (3.5), ultra-high thermal conductivity (5 times that of copper, 8 times that of aluminum, and 10 times that of aluminum nitride), high temperature resistance, and high breakdown electric field. It has great application prospects in microwave communications, 5G communication base stations, radars, and other equipment. The load is a passive device that is mainly used to absorb the power of the RF or microwave system and reduce the damage of the reflected wave to the equipment. The reliability of the load is mainly reflected in its ability to withstand power. Due to the above advantages, the diamond load has a larger power capacity and higher frequency under the same test conditions compared with the power load of the traditional AlN and BeO substrate materials.

[0003] The structure of the diamond load is composed of a front metal layer, a front resistor layer, a back metal layer and a side metal layer. The side metal layer is used to conduct the metal on the back and front to ensure good grounding. The method of forming a metal layer on the side is to cut a groove in the diamond substrate, expose the side and then sputter the film. However, diamond is extremely hard and cannot be cut by traditional grinding wheels. Only laser cutting methods can be used. However, laser cutting will convert SP3 phase diamond into SP2 phase graphite, thereby producing graphite slag. This type of slag remains on the side wall and has strong water vapor adsorption, strong adhesion and is extremely difficult to remove. Graphite has no adhesion to the sputtered metal layer, and water vapor will overflow at high temperatures. This causes the diamond side to be sputtered and then bubbled and removed after thermal testing, which seriously affects the reliability and service life of the diamond load. How to effectively clean the diamond laser grooved side and improve the adhesion of the side film layer has become a technical difficulty for current diamond edge products (such as diamond loads and diamond attenuators). Summary of the invention

[0004] The main purpose of the present application is to provide a diamond substrate and a processing method thereof, a diamond load and a preparation method thereof, so as to solve the problem that the graphite slag on the diamond substrate is difficult to clean during the traditional diamond substrate manufacturing process.

[0005] To achieve the above object, the first aspect of the present application provides a method for processing a diamond substrate, comprising the following steps:

[0006] providing a diamond sheet having opposing first and second faces;

[0007] A through groove of a predefined shape is formed on the diamond sheet by a laser cutting method, wherein the through groove penetrates the diamond sheet from the first surface to the second surface, thereby obtaining a grooved substrate;

[0008] A diamond grinding tool is used to probe into the through groove, so that at least one grinding surface of the diamond grinding tool is in close contact with the side wall of the through groove, so as to grind the side wall of the through groove to obtain the diamond substrate.

[0009] Further, the step of using a diamond grinding tool to probe into the through groove so that at least one grinding surface of the diamond grinding tool is in close contact with the side wall of the through groove to grind the side wall of the through groove to obtain the diamond substrate includes:

[0010] Selecting a diamond grinding tool that matches the size of the through groove, wherein the diamond grinding tool comprises a diamond saw blade, and the diamond saw blade comprises two opposite grinding surfaces, on which diamond particles are arranged;

[0011] Connecting the diamond saw blade to a grinder, and vertically placing the diamond saw blade into the through slot from the first surface, so that at least one of the grinding surfaces is in close contact with the side wall of the through slot;

[0012] The grinding machine is started, and the diamond saw blade is driven to rotate. The grinding surface is used to grind the side wall of the through groove. After the grinding is completed, the diamond substrate is obtained.

[0013] Furthermore, the step of starting the grinder, driving the diamond saw blade to rotate, and grinding the side wall of the through groove on the grinding surface until the grinding is completed to obtain the diamond substrate includes:

[0014] Starting the grinder, and controlling the no-load speed of the grinder to be no higher than 800 r / min;

[0015] Grinding the side wall of the through groove back and forth several times by at least one grinding surface of the diamond saw blade until the side wall of the through groove is completely ground;

[0016] The operation of the grinding machine is stopped, the slotted substrate is turned over, and the diamond saw blade is vertically placed into the through slot from the second surface so that at least one grinding surface is in close contact with the side wall of the through slot;

[0017] Restart the grinder and control the no-load speed of the grinder to be no higher than 800 r / min;

[0018] The diamond substrate is obtained by grinding the sidewalls of the through-slots reciprocatingly for several times with at least one grinding surface of the diamond saw blade until the sidewalls of the through-slots are completely ground.

[0019] Further, the predefined shape of the through groove includes that the projection of a single through groove on the first surface or the second surface is a closed pattern, the closed pattern includes a middle portion and end portions arranged at both ends of the middle portion, the middle portion is rectangular, and the end portions are arc-shaped; wherein,

[0020] The middle portion is a straight line segment. At the intersection of the circular arc and the straight line segment, the angle between the tangent of the circular arc and the straight line segment is α, and the angle α satisfies the following condition: 0°≤α<90°; preferably, the angle α satisfies the following condition: 30°≤α≤60°.

[0021] Furthermore, the predefined shape of the through groove includes: a cross-sectional shape of the through groove is a trapezoid, and the cross-sectional shape of the through groove is a surface perpendicular to the first surface or the second surface.

[0022] Furthermore, the diamond grinding tool includes a diamond saw blade, which includes two conical or truncated cone grinding surfaces symmetrically arranged along the central axis of the diamond saw blade, and diamond particles are arranged on the grinding surfaces; the main line of the cone or the truncated cone forms a first angle with the central axis, and when the diamond saw blade penetrates into the through groove, the waistline of the trapezoid forms a second angle with the central axis, and the first angle is equal to the second angle.

[0023] Furthermore, after the step of using a laser cutting method to open a through groove of a predefined shape on the diamond sheet, wherein the through groove penetrates the diamond sheet from the first surface to the second surface to obtain a grooved substrate, the step further includes:

[0024] performing a first cleaning on the slotted substrate to remove powder particles;

[0025] Cleaning the grooved substrate for a second time to remove organic oil stains;

[0026] performing a third cleaning on the grooved substrate to dehydrate;

[0027] The dehydrated grooved substrate is blown dry by inert gas.

[0028] Furthermore, after the step of drying the dehydrated grooved substrate by blowing an inert gas, the process further comprises:

[0029] The dried grooved substrate is placed in an oven for drying to obtain the diamond substrate.

[0030] Furthermore, the step of using a diamond grinding tool to probe into the through groove so that at least one grinding surface of the diamond grinding tool is in close contact with the side wall of the through groove to grind the side wall of the through groove to obtain the diamond substrate further includes:

[0031] Using a diamond grinding tool to probe into the through groove, so that at least one grinding surface of the diamond grinding tool is in close contact with the side wall of the through groove, so as to grind the side wall of the through groove;

[0032] Soak the polished grooved substrate in an acid solution at 100-110°C for tens of minutes;

[0033] The grooved substrate is taken out, rinsed with deionized water, and blown dry with inert gas to obtain the diamond substrate.

[0034] Further, the step of using a diamond grinding tool to probe into the through groove so that at least one grinding surface of the diamond grinding tool is in close contact with the side wall of the through groove to grind the side wall of the through groove to obtain the diamond substrate includes:

[0035] Using a diamond grinding tool to probe into the through groove, so that at least one grinding surface of the diamond grinding tool is in close contact with the side wall of the through groove, so as to grind the side wall of the through groove;

[0036] Using a toothbrush dipped in toothpaste, place the polished grooved substrate on a flat surface, and repeatedly wipe the areas of the first surface and the second surface of the polished grooved substrate close to the through groove;

[0037] After wiping, the grooved substrate is placed in deionized water and repeatedly cleaned with a toothbrush without toothpaste to obtain the diamond substrate.

[0038] A second aspect of the present application provides a diamond substrate, which is prepared by the above-mentioned diamond substrate processing method.

[0039] The third aspect of the present application provides a method for preparing a diamond support, wherein the diamond support is prepared using the above-mentioned diamond substrate, and the method comprises the following steps:

[0040] The second surface of the diamond substrate faces upwards, and a first film layer is sputtered onto the second surface, wherein the first film layer includes a metal film layer, as a first substrate;

[0041] The first substrate is placed with the first surface facing upwards, and a second film layer is sputtered onto the first surface, wherein the second film layer includes a resistance film layer and a metal film layer, to serve as a second substrate;

[0042] Electroplating the first film layer and the second film layer to thicken the metal film layer to serve as a third substrate;

[0043] Performing photolithography and etching on the third substrate to pattern the resistance film layer to form a fourth substrate;

[0044] The resistance film layer of the fourth substrate is subjected to thermal oxidation resistance adjustment, and thermal testing is performed at a preset temperature for several minutes to tens of minutes to obtain a fifth substrate;

[0045] The fifth substrate is laser scribing and cutting to obtain the diamond loading.

[0046] The fourth aspect of the present application provides a diamond support, characterized in that it is prepared using the above-mentioned diamond support preparation method.

[0047] The diamond substrate and its processing method, diamond load and its preparation method provided by the present application are to open a through groove of a predefined shape on the diamond sheet to be processed by a laser cutting method, and use a diamond sand grinding tool to probe into the through groove and grind the side wall of the through groove to obtain a diamond substrate. The physical grinding method can efficiently remove the graphite slag attached to the side wall of the diamond through groove, and the process is simple, simple to use, low cost, and easy to popularize, thereby effectively improving the adhesion of the film layer on the side of the diamond substrate through groove and improving the stability of the back-end product (such as diamond load); and the production is not restricted by environmental impact assessment, and the popularity is high, with good economic value and promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 A flow chart of a method for processing a diamond substrate provided in one embodiment of the present application;

[0049] Figure 2 A schematic diagram of the shape of a through groove of a diamond substrate provided in one embodiment of the present application;

[0050] Figure 3 A schematic diagram of the cross-sectional structure of a diamond saw blade provided in an embodiment of the present application after being placed in a through groove of a diamond substrate;

[0051] Figure 4 A schematic diagram of the cross-sectional structure of a diamond saw blade provided in another embodiment of the present application after being placed in a through groove of a diamond substrate;

[0052] Figure 5 A flow chart of a method for preparing a diamond support provided in one embodiment of the present application;

[0053] Figure 6 A schematic diagram of the cross-sectional structure of a diamond load provided in one embodiment of the present application.

[0054] Figure 7 The image comparison of the through groove sidewall of the diamond substrate before and after polishing in Example 1 of the present application, wherein (a) is before polishing, and (b) is after polishing;

[0055] Figure 8 The image comparison of the diamond loading of Example 1 and Comparative Example 1 of the present application after thermal testing, wherein (a) is a plan view of the diamond loading of Comparative Example 1, (b) is a partial enlarged view of the diamond loading of Comparative Example 1, (c) is a plan view of the diamond loading of Example 1, and (d) is a partial enlarged view of the diamond loading of Example 1.

[0056] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0057] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by technicians in the technical field of the present application; the terms used in the specification of the application herein are only for the purpose of describing specific embodiments and are not intended to limit the present application; the terms "including" and "having" and any variations thereof in the specification and claims of the present application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of the present application or the above-mentioned drawings are used to distinguish different objects, not to describe a specific order.

[0058] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0059] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings.

[0060] Reference Figure 1 The present application discloses a method for processing a diamond substrate, comprising the following steps:

[0061] S1: providing a diamond sheet having a first surface and a second surface opposite to each other;

[0062] S2: using a laser cutting method to open a through groove of a predefined shape on the diamond sheet, wherein the through groove penetrates the diamond sheet from the first surface to the second surface, thereby obtaining a grooved substrate;

[0063] S3: using a diamond grinding tool to probe into the through groove and grind the side wall of the through groove so that at least one grinding surface of the diamond grinding tool is in close contact with the side wall of the through groove to obtain a diamond substrate.

[0064] In the present embodiment, the diamond sheet is prepared by CVD (chemical vapor deposition), and the thickness of the diamond sheet can be selected according to the needs of the specific use scenario, and the present application does not impose any special restrictions on this. Taking the use of a diamond substrate to make a diamond load as an example, the thickness of the diamond sheet can be selected to be 0.2-0.5mm, etc., and conventional ones are 0.254mm or 0.381mm, etc. It can be understood that the first side of the diamond sheet corresponds to the first side of the slotted substrate, and also corresponds to the first side of the diamond substrate, and the second side of the diamond sheet corresponds to the second side of the slotted substrate, and also corresponds to the second side of the diamond substrate. And other substrates or loads named for the convenience of description in the specification of this application, in the description of the first side or the second side, all correspond to the first side or the second side of the diamond sheet (substrate) respectively.

[0065] In the above step S2, the shape of the through groove can be adjusted according to the needs of the specific use scenario. For example, it is a straight groove with a width of 0.2-0.25 mm. If the through groove is too wide, it will affect the coating area of ​​the diamond substrate and reduce its utilization rate. If the through groove is too narrow, it will easily lead to difficulty in laser cutting, and it is not easy to deposit a metal film layer on the side during sputtering, resulting in poor contact between the first surface and the second surface. Therefore, the width of the through groove is limited to 0.2-0.25 mm, which is convenient for laser cutting and conducive to the deposition of a metal film layer on the side wall of the through groove, and can also improve the utilization rate of the diamond substrate and save the manufacturing cost of subsequent diamond loads. The number of through grooves can be multiple, and the specific number and the spacing width between adjacent through grooves are determined according to different product sizes.

[0066] In some embodiments, the horizontal distance between the two ends of the through groove and the edge of the diamond substrate is greater than or equal to 3.5 mm. Because the groove is too close to the edge, it is easy to cause cracks in the diamond substrate. By making the horizontal distance between the two ends of the through groove and the edge of the diamond substrate greater than or equal to 3.5 mm, such as 3.5 mm or 4 mm or 4.5 mm, during or after laser cutting, cracks can be effectively prevented from occurring at the edge of the diamond substrate. Among them, laser cutting uses a laser cutting machine, such as an ultraviolet nanosecond laser cutting machine, an infrared laser cutting machine, etc.

[0067] In some embodiments, as an optional step after step S2, after laser cutting the diamond sheet to obtain the slotted substrate, the slotted substrate can be wiped back and forth with a dust-free cloth dipped in alcohol for more than 2 times, and then placed in an alcohol tank for ultrasonic treatment for more than 10 minutes, and then taken out after being blown dry with nitrogen before entering step S3. In this way, part of the slag formed on the substrate during the laser cutting process can be initially scrubbed off to prevent part of the slag from interfering with the diamond sand grinding process, etc., thereby improving the grinding effect and saving the time of subsequent grinding.

[0068] In the above step S3, the diamond grinding tool has a grinding surface, and the grinding surface is placed in the through groove so that the grinding surface is close to the side of the through groove, thereby grinding the side of the through groove. Among them, the grinding surface can be one or more, for example, two. For a diamond grinding tool with one grinding surface, the grinding surface can be first pressed against one side of the through groove, and after the grinding is completed, the direction can be adjusted to grind the other side. For a diamond grinding tool with two relative grinding surfaces, a suitable diamond grinding tool thickness specification can be selected so that the two grinding surfaces are simultaneously pressed against the two sides of the through groove, so that the two sides can be polished at the same time. It can be understood that for a diamond grinding tool with two relative grinding surfaces, only one side can be polished at a time. Preferably, the thickness of the diamond grinding tool satisfies the following relationship: 1 / 2 of the width of the through groove ≤ thickness of the diamond grinding tool ≤ width of the through groove. More preferably, the thickness of the diamond grinding tool is equal to the width of the through groove, which can ensure full contact between the side wall of the through groove and the grinding surface and has a good grinding effect. Here, the thickness of the diamond grinding tool refers to the thickness corresponding to the partial area of ​​the diamond saw blade protruding into the through groove.

[0069] In the embodiment of the present application, for the slotted substrate after laser slotting, it is easy to have residual graphite slag at the slotting location. For the graphite slag remaining on the first side and / or the second side of the slotted substrate, the prior art discloses a variety of removal methods, such as whole-surface grinding, surface wiping, etc. However, it has not been found in the prior art that multiple residual graphite slags will actually be formed on the inner side wall of the through groove of the slotted substrate during the processing process, and the graphite slag in the through groove is difficult to remove by the existing method. In this embodiment, the graphite slag attached to the through groove is removed by grinding the inner side wall of the through groove. The process is simple, not only can the graphite slag adhered to the through groove after laser slotting be cleaned, but also it is simple to use, low in cost, and easy to popularize, thereby effectively improving the adhesion of the film layer on the side of the diamond through groove and improving the stability of the back-end product (such as diamond load).

[0070] In some embodiments, a diamond grinding tool is used to probe into the through groove so that at least one grinding surface of the diamond grinding tool is in close contact with the side wall of the through groove to grind the side wall of the through groove to obtain a diamond substrate in step S3, which specifically includes the following steps:

[0071] S301: selecting a diamond grinding tool that matches the size of the through groove, wherein the diamond grinding tool includes a diamond saw blade, and the diamond saw blade includes two opposite grinding surfaces, on which diamond particles are arranged;

[0072] S302: connecting the diamond saw blade to the grinder, and vertically placing the diamond saw blade into the through groove from the first surface, so that at least one grinding surface is in close contact with the side wall of the through groove;

[0073] S303: Start the grinder, drive the diamond saw blade to rotate, and grind the grinding surface to the side wall of the through groove. After the grinding is completed, a diamond substrate is obtained.

[0074] In the embodiment of the present application, in the above step S301, the corundum saw blade can adopt an existing mature commercial product or a customized product of specific specifications. For mature commercial products, the optional thicknesses are 0.15mm, 0.2mm, 0.25mm and 0.3mm, so as to match the size of the through groove with a width of 0.2-0.25mm. The surface of the corundum saw blade is electroplated with diamond particles, which can effectively remove the graphite slag on the side of the through groove by friction, while causing almost no wear to the diamond substrate itself. Optionally, the outer diameter of the diamond saw blade is controlled to be ≥ the depth of the through groove. For example, in a specific example, an existing corundum saw blade with a thickness of 0.2mm, an outer diameter of 16mm and an inner diameter of 3mm is selected. For customized products of specific specifications, the shape and specifications of the corundum saw blade are customized according to the shape of the through hole.

[0075] In the above step S302, the slotted substrate is placed on a soft protective pad, such as a sponge, or can be held or placed on two gaskets of equal height to hollow out the through slot, and then a hand-held grinder is used. The above grinder includes a conventional grinder and also includes a low-speed electric tool such as an electric screwdriver. Part of the diamond saw blade is placed in the through slot. Usually, the diamond saw blade is circular, and the diamond saw blade placed in the through slot is usually smaller than a semicircle.

[0076] In the above step S303, the side wall of the through groove is usually repeatedly ground back and forth for several times, for example, 3-10 times, until no more black matter falls off the protective pad (for example, white sponge), or the side wall of the through groove is observed to be white without black adhesion under a microscope.

[0077] In some embodiments, the grinding machine is started, the diamond saw blade is driven to rotate, and the grinding surface is ground against the side wall of the through groove. After the grinding is completed, the step S303 of obtaining the diamond substrate specifically includes the following steps:

[0078] S3031: Start the grinder and control the no-load speed of the grinder to be no higher than 800r / min;

[0079] S3032: grinding the side wall of the through groove back and forth for several times by at least one grinding surface of the diamond saw blade until the side wall of the through groove is completely ground;

[0080] S3033: Pause the operation of the grinder, turn over the slotted substrate, and vertically place the diamond saw blade into the through slot from the second surface, so that at least one grinding surface is in close contact with the side wall of the through slot;

[0081] S3034: Start the grinder again and control the no-load speed of the grinder to be no higher than 800r / min;

[0082] S3035: reciprocatingly grinding the side wall of the through groove by at least one grinding surface of the diamond saw blade for several times until the side wall of the through groove is completely ground to obtain a diamond substrate.

[0083] In the embodiment of the present application, in the above step S3031, the rotation speed of the grinder when idling is controlled to be no higher than 800r / min, that is, the rotation speed is less than or equal to 800r / min. Because too high a rotation speed can easily cause the diamond substrate to crack, one of the difficulties in grinding the side wall of the through groove is that careless operation during the grinding process may cause the diamond substrate to crack. Therefore, it is particularly important to choose a suitable grinding speed, that is, by controlling the rotation speed of the grinder to no more than 800r / min, it can effectively grind and remove graphite and other slag on the side wall of the through groove, and can also effectively prevent the diamond substrate from cracking during the grinding process, thereby improving the effectiveness and reliability of the processing method.

[0084] In some embodiments, in the above step S3032, the above number of times can be 3-10 times. In this step, the two side walls facing the through slot can be polished separately by one polishing surface, or the two side walls facing the through slot can be polished simultaneously by two polishing surfaces, depending on the matching degree between the selected diamond saw blade and the size of the through slot.

[0085] In the above steps S3033-S3035, the slotted substrate is turned over, and a diamond saw blade is inserted from the second side to grind again to ensure that the side wall of the through slot is fully grinded. The specific grinding process is the same as steps S3031-S3032, and will not be repeated here.

[0086] This embodiment achieves sufficient grinding of the through grooves by setting appropriate grinding process parameters and facet grinding steps, reduces the problem of cracking of the diamond substrate, and improves product stability.

[0087] In some embodiments, the predefined shape of the through groove includes that the projection of a single through groove on the first surface or the second surface is a closed pattern, the closed pattern includes a middle portion and end portions arranged at both ends of the middle portion, the middle portion is rectangular, and the end portions are arc-shaped.

[0088] In some embodiments, reference Figure 2 , the end 101 of the through slot 1 is set to be an arc shape, and the middle part 102 is a rectangle, so that the structural strength of the through slot edge can be improved. Thereby, the risk of the diamond substrate cracking during the grinding of the through slot sidewall is further reduced. For conventional through slots with right-angled edges, the stress of the right-angled edges is concentrated, and the diamond substrate is prone to cracking at the right angle during the grinding process. The cross-sectional shape of the through slot can be a rectangle, and in other embodiments, it can also be other shapes.

[0089] In some embodiments, the middle portion is a straight line segment, and at the intersection of the arc and the straight line segment, the angle between the tangent of the arc and the straight line segment is α, and the angle α satisfies the following condition: 0°≤α<90°. In other embodiments, the angle α between the tangent of the arc and the straight line segment satisfies the following condition: 30°≤α≤60°. Therefore, by controlling the included angle α between the tangent of the arc and the straight line segment to meet the above conditions, especially when the condition range of 30°≤α≤60° is met, on the one hand, it is possible to prevent the arc from being too curved, that is, to prevent the depth of the arc from being too large, so that it is convenient for the diamond grinding tool (such as a diamond saw blade) to extend into the top of the arc for grinding, so as to clean the graphite and other slag on the side wall of the through groove at the arc; on the other hand, it is possible to prevent the arc from being too curved, that is, the depth of the arc is too small. When the depth of the arc is too small, it is easy to generate large internal stress at this place, which is easy to cause the diamond substrate to crack at this place. Therefore, controlling the included angle α between the tangent of the arc and the straight line segment to meet the above conditions can also effectively avoid the through groove cracking during the grinding process, that is, the occurrence of diamond substrate cracking, thereby improving the reliability of the processing method.

[0090] In some embodiments, the predefined shape of the through-channel includes: the cross-sectional shape of the through-channel is a trapezoid, and the cross-sectional shape of the through-channel is a surface perpendicular to the first surface or the second surface.

[0091] In this embodiment, the ends of the through grooves with the above-mentioned trapezoidal cross-section can also be arc-shaped with the characteristics of the above-mentioned embodiments. That is, the area of ​​the through grooves opened on the first surface is larger than the area opened on the second surface, or the area opened on the second surface is larger than the area opened on the first surface. Specifically, the diamond sheet and the laser can be adjusted to have a certain angle during laser grooving. Those skilled in the art can set it according to the specific trapezoidal size requirements. The embodiments of the present application do not specifically limit the angle. For through grooves set as trapezoidal cross-sections, on the one hand, it is convenient to observe the removal of graphite slag on the side walls of the through grooves, and on the other hand, it is also convenient to form a metal layer on the side walls of the through grooves by metal sputtering during the production process of subsequent products.

[0092] In some embodiments, the diamond grinding tool includes a diamond saw blade, which includes two conical or truncated cone grinding surfaces symmetrically arranged along the central axis of the diamond saw blade, and diamond particles are arranged on the grinding surfaces; the cone or truncated cone generatrix forms a first angle with the central axis, and when the diamond saw blade is inserted into the through groove, the waistline of the trapezoid forms a second angle with the central axis, and the first angle is equal to the second angle.

[0093] In the present embodiment, for the through groove with a trapezoidal cross section of the aforementioned embodiment, the shape of the diamond grinding tool is further specifically designed. The two grinding surfaces of a conventional diamond saw blade are planes, while the two grinding surfaces of the diamond saw blade in the present embodiment are conical or truncated cone-shaped. By setting the above-mentioned first angle and the second angle to be equal, the two grinding surfaces of the diamond saw blade can be very conveniently fitted with the two side surfaces of the through groove at the same time, thereby greatly improving the grinding efficiency, reducing the number of back and forth grinding, and thus greatly reducing the risk of cracking when grinding the through groove side of the diamond substrate. Specifically, for a through groove with a rectangular cross section, when selecting a diamond saw blade, it is necessary to match a diamond saw blade 22 of appropriate thickness so that the two side surfaces of the through groove can be fitted with the two grinding surfaces of the diamond saw blade at the same time. For through grooves of different widths, it may sometimes be difficult to match a diamond saw blade of appropriate thickness. In that case, it is necessary to grind each side separately, which increases the number of back and forth grinding. Each grinding has a certain probability of cracking of the diamond substrate. The increase in the number of grinding times undoubtedly increases the risk of cracking of the diamond substrate. Refer to Figure 3 In a specific embodiment, when the rectangular through slot 21 and the emery saw blade 22 are matched, one grinding surface 221 of the emery saw blade 22 contacts one side wall 211 of the through slot 21, while the other side wall does not contact the other grinding surface. Therefore, it is very important to select an emery saw blade of suitable matching thickness. In this embodiment, by setting the grinding surface of the emery saw blade to be conical or truncated cone, if it is cut from a plane perpendicular to the central axis, the cross-sectional shape corresponding to the grinding surface area of ​​the emery saw blade is also a trapezoid. Figure 4 In a specific embodiment, when the trapezoidal through slot 31 and the diamond saw blade 32 match, the grinding surface 321 of the diamond saw blade 32 is in contact with the side wall 311 of the through slot 31, and the other side wall 312 is also in contact with the other grinding surface 322. Since the radius of the diamond saw blade is much larger than the depth of the through slot (i.e., the distance from the first surface to the second surface), for through slots of different widths, it is only necessary to adjust the insertion depth of the diamond saw blade up and down, so that the two sides of the through slot and the two grinding surfaces of the diamond saw blade can be tightly fitted at the same time at different positions of the trapezoidal cross section of the diamond saw blade, thereby greatly improving the grinding efficiency and greatly reducing the risk of cracking when grinding the through slot side of the diamond substrate.

[0094] In some embodiments, after the step S2 of opening a through groove of a predefined shape on the diamond sheet by a laser cutting method, wherein the through groove penetrates the diamond sheet from the first surface to the second surface to obtain a grooved substrate, before the step S3 of using a diamond grinding tool to probe into the through groove so that at least one grinding surface of the diamond grinding tool is in close contact with the side wall of the through groove to grind the side wall of the through groove to obtain the diamond substrate, the method further includes:

[0095] S2021: Performing a first cleaning on the slotted substrate to remove powder particles;

[0096] S2022: cleaning the slotted substrate for a second time to remove organic oil stains;

[0097] S2023: washing the grooved substrate for a third time to dehydrate it;

[0098] S2024: Blowing the dehydrated grooved substrate dry with inert gas.

[0099] In this embodiment, in the above step S2021, the grooved substrate is ultrasonically cleaned in a first organic solvent for 10-30 minutes, and then ultrasonically cleaned in deionized water for 10-30 minutes to remove powder particles. Exemplarily, the first organic solvent used for cleaning powder particles includes organic acids, such as aliphatic monobasic, dibasic, and polybasic carboxylic acids (tartaric acid, oxalic acid, malic acid, citric acid, ascorbic acid, etc.); aromatic organic acids (benzoic acid, salicylic acid, caffeic acid, etc.); preferably, a saturated oxalic acid solution is used.

[0100] In the above step S2022, the grooved substrate is ultrasonically cleaned in a second organic solvent for 10-30 minutes, and then ultrasonically cleaned in deionized water for 10-30 minutes to remove organic oil stains. Exemplarily, the second organic solvent used for cleaning the organic oil stains includes acetone, ethyl acetate, methanol, isopropanol, chloroform, dichloromethane, dimethylformamide (DMF), dimethyl sulfoxide (DMSO), acetonitrile, etc.; preferably, acetone is used.

[0101] In the above step S2023, the grooved substrate is ultrasonically cleaned in a third organic solvent for 10-30 minutes to dehydrate without residual water stains, and oil / fingerprints and other substances can also be removed. Exemplarily, the third organic solvent used for dehydration includes ethanol, ethylene glycol, isopropanol, acetone, cyclohexanone, etc.; preferably, ethanol is used.

[0102] In the above step S2024, the dehydrated grooved substrate is blown dry by an inert gas, for example, the inert gas may include nitrogen, helium, etc.

[0103] In some embodiments, a diamond grinding tool is used to probe into the through groove so that at least one grinding surface of the diamond grinding tool is in close contact with the side wall of the through groove to grind the side wall of the through groove to obtain a diamond substrate in step S3, which specifically includes the following steps:

[0104] S30: using a diamond grinding tool to probe into the through groove, so that at least one grinding surface of the diamond grinding tool is in close contact with the side wall of the through groove, so as to grind the side wall of the through groove;

[0105] S31: soaking the polished grooved substrate in an acid solution at 100-110° C. for tens of minutes;

[0106] S32: taking out the grooved substrate, rinsing it with deionized water, and drying it with an inert gas to obtain a diamond substrate.

[0107] In some embodiments, step S31 may be to immerse the end of the through groove on the polished grooved substrate in an acid solution at 100-110° C. for tens of minutes.

[0108] In this embodiment, the acid solution in the above step S31 can be strong sulfuric acid, aqua regia (a highly corrosive mixed acid prepared by mixing concentrated hydrochloric acid and concentrated nitric acid in a ratio of 3:1), piranha solution (a mixture of concentrated sulfuric acid and 30% hydrogen peroxide (7:3)), permanganic acid, chromic acid, etc. For a diamond substrate that has been polished, the amount of the acid solution in step S31 can be very small, just enough to submerge the diamond substrate. For example, for the case of neutral cleaning in a fixture, the solution height is at least more than the substrate diameter + the fixture height, for example, 300mL to 500mL, and the acid solution can be reused. The temperature of the acid solution can be heated to 100 to 110°C in an oil bath, and after soaking for, for example, 10-30 minutes, it is rinsed with a large amount of deionized water for 5-10 minutes, and then blown dry with an inert gas, such as nitrogen. This embodiment combines physical grinding with chemical dissolution cleaning, and adopts the method of first grinding and then chemical dissolution cleaning. On the one hand, the graphite and other slags attached to the side walls of the non-end areas of the through groove can be completely removed by physical grinding, and the slags attached to the arc side walls of the end areas of the through groove can be completely or partially removed; on the other hand, the substrate after grinding is supplemented by chemical solvents, and the areas not polished by the diamond grinding tool (especially the arc-shaped through groove end areas) are further cleaned to achieve comprehensive and effective cleaning of all areas of the through groove side walls, making the cleaning more thorough, thereby further improving the reliability and stability of the use of diamond loads and other products prepared by the diamond substrate processed by the method, and can effectively improve the yield of diamond loads and other products, and reduce the production cost of diamond loads and other products. However, the method of simply using chemical dissolution cleaning requires the use of a large amount of chemical solvents with strong oxidants (such as strong acids, etc.), which often requires the use of multiple strong acids, and requires repeated immersion cleaning for many times, the cleaning efficiency is low, and the amount of chemical solvents used is large, which is not friendly to the environment.

[0109] In some embodiments, a diamond grinding tool is used to probe into the through groove so that at least one grinding surface of the diamond grinding tool is in close contact with the side wall of the through groove to grind the side wall of the through groove to obtain a diamond substrate step S3, which specifically includes:

[0110] S30: using a diamond grinding tool to probe into the through groove, so that at least one grinding surface of the diamond grinding tool is in close contact with the side wall of the through groove, so as to grind the side wall of the through groove;

[0111] S33: using a toothbrush dipped in toothpaste, placing the polished grooved substrate on a flat surface, and repeatedly wiping the areas near the through grooves on the first surface and the second surface of the polished grooved substrate;

[0112] S34: After wiping, the grooved substrate is placed in deionized water and repeatedly cleaned with a toothbrush without toothpaste to obtain a diamond substrate.

[0113] In this embodiment, during the laser cutting process, in addition to graphite slag attached to the side of the through groove, there may also be a small amount of attached sedimentary material on the edge of the first side / second side of the diamond substrate near the through groove. In order to ensure that the graphite slag near the groove on the first side / second side is removed cleanly, further cleaning is performed through the above steps S33-S34 after polishing. Specifically, use a fine-bristled hard toothbrush dipped in baking soda toothpaste, place the diamond substrate in a culture dish or a flat place, and repeatedly wipe the grooves, 3-10 times back and forth for each groove. After wiping, put deionized water in the culture dish, and repeatedly clean it with a toothbrush without toothpaste until no foam is generated. After wiping, put it in an alcohol tank for ultrasonic treatment for 10 minutes, and blow it dry with nitrogen and take it out. Brushing with a toothbrush can be more gentle and sufficient to remove attachments. When cleaning the graphite slag on the surface, there is no through groove limit, so it is difficult to control the grinding range if diamond grinding is used, which can easily cause the diamond substrate to shift and damage the surface of the diamond substrate, thereby affecting the film-forming performance in subsequent product manufacturing.

[0114] In some other embodiments, the above steps S31-S32 may also be arranged after S33-S34.

[0115] In some other embodiments, after the step S2 of using a laser cutting method to open a through groove of a predefined shape on the diamond sheet, wherein the through groove penetrates the diamond sheet from the first surface to the second surface to obtain a grooved substrate, the step further includes:

[0116] S2025: performing a first cleaning of the slotted substrate to remove powder particles;

[0117] S2026: The slotted substrate is cleaned for a second time to remove organic oil stains;

[0118] S2027: The slotted substrate is cleaned for a third time to dehydrate;

[0119] S2028: Blowing the dehydrated grooved substrate dry with an inert gas;

[0120] S2029: Put the dried slotted substrate into an oven for drying to obtain a diamond substrate.

[0121] The steps of cleaning and drying with inert gas in the above steps S2025-S2028 are basically the same as the above steps S2021-S2024. The implementation of the specific process refers to the above steps S2021-S2024, which will not be repeated here. The difference here is that the slotted substrate that is repeatedly cleaned and dried in steps S2025-S2028 refers to the slotted substrate that has been polished in step S30, while the slotted substrate that is repeatedly cleaned and dried in steps S2021-S2024 refers to the slotted substrate that has been laser slotted in step S2.

[0122] In the above step S2029, the grooved substrate after being blown dry by the inert gas is placed in a clean oven and baked at 150-200° C. for 0.5-2 hours to fully dry out the moisture, thereby obtaining a diamond substrate.

[0123] In some other embodiments, the above steps S2025-S2028 can also be arranged after the grooved substrate is cleaned with a toothbrush in step S34.

[0124] Some embodiments of the present application further disclose a diamond substrate, which is prepared by the processing method of the diamond substrate of any of the aforementioned embodiments.

[0125] The diamond substrate of this embodiment has the graphite slag adhered in the through groove cleaned up, which can effectively improve the adhesion of the diamond side film layer and enhance the stability of the back-end product (such as the diamond load sheet); and the product has a high yield rate and low cost, and has good economic value and market competitiveness.

[0126] Reference Figure 5 Some embodiments of the present application disclose a method for preparing a diamond load, using the aforementioned diamond substrate to prepare a diamond load, comprising the following steps:

[0127] T1: facing the second surface of the diamond substrate upward, sputtering a first film layer onto the second surface, the first film layer including a metal film layer, as a first substrate;

[0128] T2: placing the first surface of the first substrate upward, and sputtering a second film layer onto the first surface, the second film layer including a resistance film layer and a metal film layer, as a second substrate;

[0129] T3: Electroplating the first film layer and the second film layer to thicken the metal film layer as the third substrate;

[0130] T4: performing photolithography etching on the third substrate to pattern the resistance film layer to form a fourth substrate;

[0131] T5: thermally oxidizing the resistance film layer of the fourth substrate and performing a thermal test at a preset temperature for several minutes to tens of minutes to obtain a fifth substrate;

[0132] T6: Perform laser scribing and cutting on the fifth substrate to obtain diamond loading.

[0133] In this embodiment, in the above step T1, the second side of the diamond substrate is placed upward, and a first film layer is sputtered by a magnetron sputtering machine, wherein the first film layer includes at least a metal film layer, such as an Au film layer. In an exemplary embodiment, Ti, Ni, and Au film layers are sputtered respectively, and their thicknesses are 0.1um, 1.2um, and 0.1um, respectively. The diamond substrate after sputtering the first film layer is then cleaned, exemplarily, by ultrasonication in acetone for 10 minutes, overflow ultrasonication in deionized water for 10 minutes, and ultrasonication in anhydrous ethanol for 10 minutes, and then dried with nitrogen and placed in a clean oven at 150°C for 1 hour for standby use. During the sputtering process of the first film layer on the second side, the first film layer material will also be deposited on the sidewalls of the through grooves, thereby forming a metal layer on the sidewalls.

[0134] In the above step T2, the first surface of the diamond substrate is facing upward, and a second film layer is sputtered by a magnetron sputtering machine, wherein the resistance film layer includes, for example, TaN and WTi film layers, and the metal film layer includes, for example, Au film layers. In an exemplary embodiment, TaN, WTi, and Au film layers are sputtered respectively, and the TaN square resistance is designed to be 40-45 ohms / square, and the thicknesses of WTi and Au are 0.1um and 0.1um respectively. Similarly, in the process of sputtering the second film layer on the second surface, the metal film layer material in the second film layer can be controlled to be deposited in the direction of the through-groove side wall to further improve the metal layer forming the side wall.

[0135] In the above step T3, an electroplating system is used to thicken the film layers on the first and second surfaces by electroplating. In an exemplary embodiment, for example, a cyanide gold salt electroplating system is used to thicken the Au film layer to 3.5-4um on the front side and 0.5-1um on the back side to meet the requirements of back welding and front bonding. It is understandable that in this process, the metal layer on the side wall of the through groove is also thickened.

[0136] In the above step T4, the above photolithography etching may be performed once or multiple times. In an exemplary embodiment, the above photolithography etching includes two photolithography etchings, specifically:

[0137] Adopt the glue spraying process, first spray the photoresist on the second side, bake the hard film, then spray the glue on the second side, after the pre-baking is completed, perform the first exposure photolithography, after photolithography, develop, after deionization rinsing, blow dry with nitrogen, and bake the hard film;

[0138] Use Au and WTi etching solution to etch off the Au film first, then rinse it with deionized water, blow it dry with nitrogen, and then etch the WTi film. After etching, remove the glue in the degumming solution, rinse it with deionized water, and blow it dry with nitrogen.

[0139] Adopt the glue spraying process, first spray the photoresist on the first side, bake the hard film, then spray the glue on the first side, after the pre-baking is completed, perform the second exposure and overlay, develop after photolithography, blow dry with nitrogen after deionization rinsing, and bake the hard film;

[0140] Use TaN etching solution to etch away the TaN film layer. After completion, remove the glue in the glue removal solution, rinse with deionized water and blow dry with nitrogen.

[0141] In the above step T5, in a specific embodiment, the above thermal oxidation resistance adjustment process includes: in the hot plate atmosphere environment, the temperature is adjusted to 300°C, the TaN resistance accuracy requirement is 50Ω±5%, that is, 47.5-52.2Ω, the resistance adjustment time is 30-60min, and the resistance is tested with an 8-bit half-resistance tester to an average resistance of ≥47.5Ω. The above thermal assessment process includes: using a conventional metal electric heating plate that can be heated, first adjusting the temperature of the hot plate to a preset temperature (usually above 300°C, such as 300-350°C), after the temperature reaches the preset temperature, placing the fourth substrate after thermal oxidation resistance adjustment on the hot plate, and starting to time until the preset time is reached and heating is stopped (the thermal assessment time varies according to needs, generally 5-15min, such as 10min), removing the fifth substrate at this time (i.e. the fourth substrate after thermal oxidation resistance adjustment and thermal assessment) from the hot plate, and after it cools down, using a microscope to observe whether there are bubbling, demoulding, etc. on its side. Through thermal testing, the load effect of the metal film layer (especially the side metal layer at the through groove) can be tested.

[0142] In the above step T6, a UV nanosecond laser is used to cut a groove along the center of the unit size edge line, and a splitting machine is used to split the unit into individual load units; preferably, the groove depth is greater than 1 / 2 of the diamond substrate thickness.

[0143] In this embodiment, the diamond load is further prepared using the diamond substrate prepared by the aforementioned method. It can be clearly seen that the graphite black before cleaning is cleaned, and no bubbling or molten residue remains after a 320°C thermal test, and the product yield is greatly improved.

[0144] In some embodiments, after the above step T5, the following may also be included: T7: After the thermal test is completed, the surface and the through grooves of the diamond load are visually inspected under a microscope with a magnification of 50-200 times, and the diamond loads without bubbles or melts in the through grooves are sorted out.

[0145] In some embodiments, after the above step T6, it may also include: T8: Perform visual inspection of the appearance, size, film thickness, bonding strength, and side 3M tape pull test on a single load unit, and put qualified products into storage.

[0146] Some embodiments of the present application disclose a diamond support, which is prepared by the aforementioned method for preparing a diamond support. Figure 6 The diamond load includes a first surface 51 and a second surface 52 , and a plurality of through grooves 53 are provided on the diamond load. The first surface 51 includes a first metal film layer area 511 and a resistor film layer area 512 , and the second surface 52 includes a second metal film layer area 521 . The side walls of the through grooves 53 are covered with a side metal film layer 531 .

[0147] The diamond load of this embodiment does not produce bubbles or molten residue after a 320° C. thermal test, and the product yield is greatly improved.

[0148] The following is a comparative explanation through specific embodiments and comparative examples.

[0149] Embodiment 1

[0150] Grooving process:

[0151] (1) A circular diamond sheet with a thickness of 0.381 mm and a diameter of 65 mm was selected, and a through groove was cut on the diamond sheet using a UV nanosecond laser cutting machine. The width of the groove was 0.2 mm, the edge of the groove was semicircular, and the distance between the arc and the edge of the substrate was 3.5 mm. After laser cutting, the grooved substrate was wiped back and forth twice with a dust-free cloth dipped in alcohol. After wiping, it was placed in an alcohol tank for ultrasonic treatment for 10 min, and then dried with nitrogen to obtain the grooved substrate.

[0152] Graphite slag removal process:

[0153] (2) Place the slotted substrate on a sponge, and fix a diamond saw blade with a thickness of 0.2 mm, an outer diameter of 16 mm, and an inner diameter of 3 mm on a small grinder. Set the speed to 800 r / min, and grind along the length of the slot. After grinding back and forth 3-10 times, turn it over and continue grinding for 3-10 times until the side wall is white and free of black adhesion when observed under a microscope. Then, use a fine-bristled hard toothbrush dipped in baking soda toothpaste, place the slotted substrate in a plastic culture dish, and repeatedly wipe the slots. After wiping, replace the deionized water in the culture dish, and repeatedly clean it with a toothbrush without toothpaste until no foam is generated. After wiping, put it in an alcohol tank for ultrasonic treatment for 10 minutes, blow dry with nitrogen, and take it out.

[0154] (3) Place the polished slotted substrate flat in a Teflon fixture, soak it in a small amount of strong sulfuric acid, heat it in an oil bath at 100-110°C, soak it for 30 minutes, rinse it with a large amount of flowing deionized overflow for 5 minutes, and then blow it dry with nitrogen.

[0155] (4) The treated grooved substrate was ultrasonically cleaned in a saturated oxalic acid solution for 30 minutes, then overflowed in deionized water for 10 minutes, then ultrasonically cleaned in acetone for 10 minutes, overflowed in deionized water for 10 minutes, and ultrasonically cleaned in anhydrous ethanol for 10 minutes. After drying with nitrogen, the substrate was placed in a clean oven and baked at 150° C. for 1 hour to obtain a diamond substrate.

[0156] Diamond loading preparation process:

[0157] (5) With the second side of the diamond substrate facing upward, a magnetron sputtering machine was used to sputter Ti, Ni, and Au film layers, with thicknesses of 0.1 um, 1.2 um, and 0.1 um, respectively.

[0158] (6) The diamond substrate after sputtering Ti, Ni, and Au film layers was ultrasonically treated in acetone for 10 minutes, in deionized water overflow for 10 minutes, and in anhydrous ethanol for 10 minutes. After being blown dry with nitrogen, the substrate was placed in a clean oven and baked at 150° C. for 1 hour for use as the first substrate.

[0159] (7) With the first surface of the first substrate facing upward, TaN, WTi, and Au film layers are sputtered respectively using a magnetron sputtering machine, wherein the TaN square resistance is designed to be 40-45 ohms / square, and the thicknesses of the WTi film layer and the Au film layer are 0.1 um and 0.1 um respectively.

[0160] (8) Using a cyanide gold salt electroplating system, the double-sided film layer is electroplated to thicken to 3.5-4um on the front side and 0.5-1um on the back side to meet the requirements of back welding and front bonding.

[0161] (9) Using the spray glue process, first spray glue on the second side, bake the hard film, then spray glue on the first side, after the pre-bake is completed, perform the first exposure lithography, after lithography, develop, deionize and rinse, blow dry with nitrogen, and bake the hard film

[0162] (10) Use Au and WTi etching solutions to first etch off the Au film layer, then rinse it in deionized water, blow dry it with nitrogen, and then etch the WTi film layer. After etching, remove the glue in the degumming solution, rinse it with deionized water, and blow dry it with nitrogen.

[0163] (11) The glue spraying process is adopted. The back side is first sprayed with glue. After the hard film is baked, the glue is sprayed on the front side again. After the pre-baking is completed, the second exposure and overlay are performed. After photolithography, the development is performed, the deionized water is rinsed, and the nitrogen is blown dry, and the hard film is baked.

[0164] (12) Use TaN etching solution to etch away the TaN film layer. After completion, remove the glue in the glue removal solution, rinse with deionized water, and blow dry with nitrogen.

[0165] (13) The resistance on the front side of the etched diamond substrate is thermally oxidized and adjusted. In the hot plate atmosphere, the temperature is controlled at 300°C. The TaN resistance accuracy requirement is 50Ω±5%, i.e., 47.5-52.2Ω. The adjustment time is 30-60min. The resistance is tested with an 8-bit half-value resistance tester until the average resistance is ≥47.5Ω. Then, the hot plate temperature is adjusted to 320°C. The substrate is taken out after 5 minutes of thermal testing.

[0166] (14) After the thermal assessment is completed, the substrate surface and channels are visually inspected under a microscope at 50-200 times magnification.

[0167] (15) A UV nanosecond laser is used to cut a groove with a depth greater than 1 / 2 of the substrate thickness along the center of the edge line of the load unit, and a splitting machine is used to split the load units into individual load units.

[0168] (16) Conduct 100% visual inspection of appearance, size, film thickness, bonding strength, and side 3M tape pull-out test on each load unit, and qualified products will be put into storage.

[0169] Comparative Example 1

[0170] The groove opening process and diamond loading preparation process of Comparative Example 1 are the same as those of Example 1, except that the graphite slag removal process adopts the following steps:

[0171] Use chromic acid to heat to 70℃ and ultrasonicate for 10 minutes;

[0172] Use 20% hydrofluoric acid at room temperature and ultrasonic for 10 minutes;

[0173] Rinse with deionized water for 2 minutes;

[0174] Use 3% alkaline surfactant, heat to 80°C, and ultrasonicate for 20 minutes;

[0175] Rinse with deionized water 3 times;

[0176] Heat to 80°C with hot water and ultrasonicate for 20 minutes;

[0177] Rinse with deionized water 6 times;

[0178] Use anhydrous ethanol at room temperature and ultrasonicate for 10 minutes;

[0179] The substrate was baked at 100° C. for 1 hour.

[0180] The diamond substrate prepared in Example 1 after grooving and cleaning was observed under a microscope. The results are as follows: Figure 7 As shown, Figure 7 (a) is a picture of the side wall of the through slot before cleaning, showing that a lot of black graphite slag is attached to its surface; Figure 7 (b) is a picture of the side wall of the through slot after cleaning. Its surface is white without any black attachments, and it can be clearly seen that the graphite slag has been cleaned. Figure 7 (a) with Figure 7 By comparing with (b), it can be seen that the processing method of the diamond substrate provided in the embodiment of the present application has a good effect of removing graphite slag.

[0181] After the thermal test of the diamond load prepared in Example 1 and the diamond load prepared in Comparative Example 1 in step (14) was completed, the film adhesion effect at the diamond load groove was observed under a microscope as follows: Figure 8 shown. Figure 8 (a) and (b) are partial pictures of diamond loading prepared in Comparative Example 1. Figure 8 (c) and (d) are partial pictures of the diamond loading prepared in Example 1. Figure 8 As can be seen in (a), there is obvious bubbling in the direction indicated by the arrow. Figure 8 The oval area in (b) has obvious slag residue; Figure 8 The metal film layer attached to the through groove in (c) and (d) is intact, no bubbling phenomenon occurs, and no residual molten residue is observed. It can be seen that the diamond load provided in the embodiment of the present application has good adhesion on the diamond substrate, especially on the side wall of the diamond basic through groove after thermal assessment. Compared with the comparative example 1, the yield of the diamond load can be greatly improved from 50% to 85%, which has good economic value and promotion value. It is shown that compared with the prior art, the diamond substrate obtained by the processing method of the diamond substrate provided in the embodiment of the present application has a good cleaning effect on the slag such as graphite attached to the side wall of the through groove, which is conducive to metal coating thereon, etc., and can effectively improve the yield and reliability of products manufactured therefrom, such as diamond loads.

[0182] Obviously, the embodiments described above are only some embodiments of the present application, rather than all embodiments. The preferred embodiments of the present application are given in the accompanying drawings, but they do not limit the patent scope of the present application. The present application can be implemented in many different forms. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present application more thorough and comprehensive. Although the present application is described in detail with reference to the aforementioned embodiments, for those skilled in the art, it is still possible to modify the technical solutions recorded in the aforementioned specific implementation methods, or to perform equivalent replacement of some of the technical features therein. Any equivalent structure made using the contents of the specification and drawings of this application, directly or indirectly used in other related technical fields, is similarly within the scope of patent protection of this application.

Claims

1. A method for processing a diamond substrate, characterized in that: The steps include: providing a diamond sheet having opposing first and second faces; A through groove of a predefined shape is formed on the diamond sheet by a laser cutting method, wherein the through groove penetrates the diamond sheet from the first surface to the second surface, thereby obtaining a grooved substrate; A diamond grinding tool is used to probe into the through groove, so that at least one grinding surface of the diamond grinding tool is in close contact with the side wall of the through groove, so as to grind the side wall of the through groove to obtain the diamond substrate.

2. The method for processing a diamond substrate according to claim 1, wherein: The step of using a diamond grinding tool to probe into the through groove so that at least one grinding surface of the diamond grinding tool is in close contact with the side wall of the through groove to grind the side wall of the through groove to obtain the diamond substrate includes: Selecting a diamond grinding tool that matches the size of the through groove, wherein the diamond grinding tool comprises a diamond saw blade, and the diamond saw blade comprises two opposite grinding surfaces, on which diamond particles are arranged; Connecting the diamond saw blade to a grinder, and vertically placing the diamond saw blade into the through slot from the first surface, so that at least one of the grinding surfaces is in close contact with the side wall of the through slot; The grinding machine is started, and the diamond saw blade is driven to rotate, and the grinding surface is used to grind the side wall of the through groove. After the grinding is completed, the diamond substrate is obtained.

3. The method for processing a diamond substrate according to claim 2, wherein: The step of starting the grinder, driving the diamond saw blade to rotate, grinding the grinding surface to grind the side wall of the through groove, and obtaining the diamond substrate after the grinding is completed includes: Starting the grinder, and controlling the no-load speed of the grinder to be no higher than 800 r / min; Grinding the side wall of the through groove back and forth several times by at least one grinding surface of the diamond saw blade until the side wall of the through groove is completely ground; The operation of the grinding machine is stopped, the slotted substrate is turned over, and the diamond saw blade is vertically placed into the through slot from the second surface so that at least one grinding surface is in close contact with the side wall of the through slot; Restart the grinder and control the no-load speed of the grinder to be no higher than 800 r / min; The diamond substrate is obtained by grinding the sidewalls of the through-slots reciprocatingly for several times with at least one grinding surface of the diamond saw blade until the sidewalls of the through-slots are completely ground.

4. The method for processing a diamond substrate according to claim 1, wherein: The predefined shape of the through slot includes that the projection of a single through slot on the first surface or the second surface is a closed pattern, the closed pattern includes a middle portion and end portions arranged at both ends of the middle portion, the middle portion is rectangular, and the end portions are arc-shaped; wherein, The middle portion is a straight line segment. At the intersection of the circular arc and the straight line segment, the angle between the tangent of the circular arc and the straight line segment is α, and the angle α satisfies the following condition: 0°≤α<90°; preferably, the angle α satisfies the following condition: 30°≤α≤60°.

5. The method for processing a diamond substrate according to claim 1, wherein: The predefined shape of the through groove includes: the cross-section of the through groove is a trapezoid, and the cross-section of the through groove is a surface perpendicular to the first surface or the second surface.

6. The method for processing a diamond substrate according to claim 5, wherein: The diamond grinding tool includes a diamond saw blade, which includes two conical or truncated cone grinding surfaces symmetrically arranged along the central axis of the diamond saw blade, and diamond particles are arranged on the grinding surfaces; the generatrix of the cone or the truncated cone forms a first angle with the central axis, and when the diamond saw blade penetrates into the through groove, the waistline of the trapezoid forms a second angle with the central axis, and the first angle is equal to the second angle.

7. The method for processing a diamond substrate according to claim 1, wherein: After the step of using a laser cutting method to open a through groove of a predefined shape on the diamond sheet, wherein the through groove penetrates the diamond sheet from the first surface to the second surface to obtain a grooved substrate, the step further includes: performing a first cleaning on the slotted substrate to remove powder particles; Cleaning the grooved substrate for a second time to remove organic oil stains; washing the grooved substrate for a third time to dehydrate the substrate; The dehydrated grooved substrate is blown dry by inert gas.

8. The method for processing a diamond substrate according to claim 7, wherein: After the step of drying the dehydrated grooved substrate by blowing inert gas, the method further comprises: The dried grooved substrate is placed in an oven for drying to obtain the diamond substrate.

9. The method for processing a diamond substrate according to claim 1, wherein: The step of using a diamond grinding tool to probe into the through groove so that at least one grinding surface of the diamond grinding tool is in close contact with the side wall of the through groove to grind the side wall of the through groove to obtain the diamond substrate includes: Using a diamond grinding tool to probe into the through groove, so that at least one grinding surface of the diamond grinding tool is in close contact with the side wall of the through groove, so as to grind the side wall of the through groove; Soak the polished grooved substrate in an acid solution at 100-110°C for tens of minutes; The grooved substrate is taken out, rinsed with deionized water, and blown dry with inert gas to obtain the diamond substrate.

10. The method for processing a diamond substrate according to claim 1, wherein: The step of using a diamond grinding tool to probe into the through groove so that at least one grinding surface of the diamond grinding tool is in close contact with the side wall of the through groove to grind the side wall of the through groove to obtain the diamond substrate includes: Using a diamond grinding tool to probe into the through groove, so that at least one grinding surface of the diamond grinding tool is in close contact with the side wall of the through groove, so as to grind the side wall of the through groove; Using a toothbrush dipped in toothpaste, place the polished grooved substrate on a flat surface, and repeatedly wipe the areas of the first surface and the second surface of the polished grooved substrate close to the through groove; After wiping, the grooved substrate is placed in deionized water and repeatedly cleaned with a toothbrush without toothpaste to obtain the diamond substrate.

11. A diamond substrate, characterized in that: The diamond substrate is prepared by the processing method of the diamond substrate as described in any one of claims 1 to 10.

12. A method for preparing a diamond support, characterized in that: The preparation of the diamond support using the diamond substrate as claimed in claim 11 comprises the following steps: The second surface of the diamond substrate faces upwards, and a first film layer is sputtered onto the second surface, wherein the first film layer includes a metal film layer, as a first substrate; The first substrate is placed with the first surface facing upwards, and a second film layer is sputtered onto the first surface, wherein the second film layer includes a resistance film layer and a metal film layer, to serve as a second substrate; Electroplating the first film layer and the second film layer to thicken the metal film layer to serve as a third substrate; Performing photolithography and etching on the third substrate to pattern the resistance film layer to form a fourth substrate; The resistance film layer of the fourth substrate is subjected to thermal oxidation resistance adjustment, and thermal testing is performed at a preset temperature for several minutes to tens of minutes to obtain a fifth substrate; The fifth substrate is laser scribing and cutting to obtain the diamond loading.

13. A diamond support, characterized in that: The diamond-loaded material is prepared by the method for preparing the diamond-loaded material as claimed in claim 12.

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