High-strength and high-thermal-conductivity silicon nitride ceramic substrate and preparation process thereof
By adding carbon black to the silicon nitride ceramic substrate preparation process and adopting a two-step heating and sintering process, the thermal conductivity and bending strength of the ceramic substrate are improved, and the cutting path is adjusted by dividing the adsorption tube, the rear edge of the ceramic substrate is solved. The problem of intactness achieves one-step laser cutting and efficient segmentation.
Patent Information
- Application Number
- CN202411361836.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-27
- Publication Date
- 2024-12-13
AI Technical Summary
In the existing ceramic substrate cutting process, the edges of the substrate are uneven after cutting, which requires secondary separation and grinding, resulting in rough cross-sections and reserved cutting depth, resulting in complex segmentation processes.
The preparation process of silicon nitride ceramic substrates with high strength and high heat conductivity is adopted. By adding carbon black to the raw materials and adopting a two-step heating and sintering process, the lattice oxygen content of silicon nitride ceramics is reduced, and the thermal conductivity and bending strength are improved; , divide the vacuum adsorption platform into movable adsorption tubes, adjust the cutting path to avoid reserved depth, and simplify the segmentation process.
A one-step laser cutting is achieved to avoid secondary separation, improve the flatness and thermal conductivity of the edge of the substrate, and simplify the segmentation process.
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Figure CN119115247A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of ceramic substrate processing, and in particular to a high-strength and high-thermal-conductivity silicon nitride ceramic substrate and a preparation process thereof. Background Art
[0002] The ceramic substrate cutting process is a complex and sophisticated technology that is widely used in industries such as electronics, optoelectronics, and semiconductors. The following are the general steps of the ceramic substrate cutting process: First, you need to select the appropriate ceramic material, common ones are aluminum oxide (Al2O3), aluminum nitride (AlN), and silicon nitride (Si3N4); clean the ceramic substrate to ensure that there are no impurities or contaminants. Then perform a quality check to ensure that the substrate meets the cutting requirements; use a laser scriber or a mechanical scriber to scribe the surface of the ceramic substrate; use a high-power laser beam for cutting, laser cutting can achieve high precision and low damage, especially suitable for thin ceramic substrates; after cutting, there may be burrs or debris on the edge of the substrate. It is necessary to remove burrs through processes such as edge grinding or polishing to ensure smooth edges; clean the cut substrate again to remove the cutting fluid and debris remaining during the processing, and then dry it.
[0003] The patent publication number CN106891094A discloses a laser cutting machine workbench for copper-clad ceramic substrates, including: a workbench and a workbench bottom plate, the workbench bottom plate is provided on the workbench, and the workbench bottom plate is provided with a bottom plate air suction hole; and also includes a cover plate, the cover plate is provided on the surface of the workbench bottom plate, the workbench bottom plate is provided with a bottom plate countersunk hole, the cover plate is provided with cover plate air suction holes arranged in the same manner as the bottom plate air suction holes and cover plate countersunk holes connected to the bottom plate countersunk holes. The present invention arranges a layer of cover plate on the surface of the lightweight work platform bottom plate so that the alumina ceramic only contacts the cover plate. Since the cover plate has high hardness and is not easy to wear, it ensures that the flatness of the work platform bottom plate does not change, thereby improving the yield of the cutting product.
[0004] The prior art has the following defects: The existing technology usually uses an integral adsorption platform to fix the ceramic substrate, and then uses laser cutting to retain a certain cutting depth, and then puts the cut set substrate into a slicer for slices, and grinds to remove burrs after slices. In this way, the uncut parts are separated by breaking, which is easy to cause uneven cut surfaces, and secondary grinding is required to achieve smooth edges of the separated ceramic substrates. Summary of the invention
[0005] In view of the above problems in the prior art, a high-strength and high-thermal-conductivity silicon nitride ceramic substrate and a preparation process thereof are proposed.
[0006] In one aspect of the present application, a process for preparing a high-strength and high-thermal-conductivity silicon nitride ceramic substrate is provided, the purpose of which is to enable laser cutting of the ceramic substrate in one step, penetrate the ceramic substrate, and completely separate the ceramic substrate to avoid secondary separation and rough cross-section.
[0007] The technical solution of the present invention is: a process for preparing a high-strength and high-thermal-conductivity silicon nitride ceramic substrate, comprising the following steps: In the first step, silicon nitride powder, sintering aid, carbon black, triethyl phosphate and solvent are mixed for the first time by ball milling; In the second step, after the first mixing, polyvinyl butyral and polyethylene glycol are added, and the mixture is mixed for the second time by ball milling to obtain a slurry; The third step is to pour the slurry into a container and place it in a vacuum degassing machine for degassing; The fourth step is to prepare a thin sheet green blank by tape casting method from the deaerated slurry; the fifth step is to place the thin sheet green blank in a debinding furnace for debinding treatment; Step 6: Place the debinding green blank in a high-temperature sintering furnace for sintering to obtain a silicon nitride ceramic substrate; Step 7: placing the cooled ceramic substrate on a cutting device to cut the ceramic substrate into blocks; In the eighth step, the cut ceramic substrate is placed in a grinding device for grinding to remove burrs and broken edges after cutting.
[0008] By adopting the above scheme, carbon black is added to the raw material ratio and a two-step heating and sintering process is used to allow the carbon black and the oxygen impurities in silicon nitride to fully react chemically under appropriate temperature and atmosphere conditions, effectively reducing the lattice oxygen content of the silicon nitride ceramic, thereby improving its thermal conductivity, and making the prepared silicon nitride ceramic substrate have excellent properties of high thermal conductivity and high bending strength.
[0009] Furthermore, the cutting device includes a bracket, a movable component arranged on the bracket, a laser cutting head arranged on the movable component, a plurality of adsorption tubes arrayed in the bracket, through hole 1 and through hole 2 respectively arranged on the plurality of adsorption tubes, the through hole 1 being arranged along the front-to-back direction, the through hole 2 being arranged along the left-to-right direction, and also includes a plurality of sliding rods 1 penetrating the plurality of through holes 1 and a plurality of sliding rods 2 penetrating the plurality of through holes 2, the plurality of sliding rods 1 being provided with left-right sliding components for controlling the plurality of sliding rods 1 to slide in the left-to-right direction, the plurality of sliding rods 2 being provided with front-to-back sliding components for controlling the plurality of sliding rods 2 to slide in the front-to-back direction, the hole walls of the through hole 1 and the through hole 2 are not connected to the inner cavity of the adsorption tube, the upper end of the adsorption tube is provided with an adsorption hole, and the lower ends of the plurality of adsorption tubes are connected to the vacuum pump through flexible pipes.
[0010] By adopting the above scheme, the vacuum adsorption platform is divided into several movable adsorption tubes, and the position of the adsorption tube is adjusted by sliding the adsorption tube on slide bar 1 and slide bar 2, so that the cutting path corresponds to the gap between the several adsorption tubes, so that the laser cutting head can completely penetrate the substrate when cutting the substrate, avoiding reserving depth during cutting, and then splitting by a splitting device, which simplifies the splitting process and improves the flatness of the edge of the substrate after splitting.
[0011] Furthermore, the left and right sliding components include a support plate symmetrically arranged on the front and rear sides of the bracket, a slide groove 1 horizontally arranged on the support plate 1, a connecting rod 1 cross-arranged on one side of a slide rod 1, and the connecting rods on multiple slide rods 1 are hinged to each other to form a retractable connecting rod mechanism, and also include a connecting plate 1 arranged at the hinge point at the rightmost end of the connecting rod 1, a motor 1 arranged on the support plate 1 on the same side as the connecting rod, and a threaded shaft 1 arranged on the main shaft of the motor 1, the threaded shaft 1 is threadedly connected to the connecting plate 1, the slide rod 1 located in the middle is fixedly connected to the support plate 1, and the two ends of the remaining slide rods slide in the slide groove 1.
[0012] By adopting the above scheme, by setting up left and right sliding components, the connecting rod mechanism drives multiple sliding rods to move symmetrically and equidistantly with the center sliding rod as the central axis, and then drives several adsorption tubes to move equidistantly in the left and right directions, so as to adapt to different cutting specifications and cutting paths.
[0013] Furthermore, the front and rear sliding components include two support plates symmetrically arranged on the left and right sides of the bracket, two slide grooves horizontally arranged on the two support plates, and two connecting rods cross-arranged on one side of the two slide rods. The two connecting rods on multiple two slide rods are hinged to each other to form a retractable connecting rod mechanism, and also include two connecting plates arranged at the hinge point at the rightmost end of the two connecting rods, two motors arranged on the two support plates on the same side as the two connecting rods, and two threaded shafts arranged on the main shaft of the two motors. The two threaded shafts are threadedly connected to the two connecting plates, the two slide rods located in the middle are fixedly connected to the two support plates, and the other two ends of the two slide rods slide in the two slide grooves.
[0014] By adopting the above scheme, by setting up front and rear sliding components, the connecting rod mechanism drives multiple sliding rods to move symmetrically and equidistantly with the center sliding rod as the central axis, and then drives several adsorption tubes to move equidistantly in the front and rear directions, so as to adapt to different cutting specifications and cutting paths.
[0015] Furthermore, the moving assembly includes a left-right moving assembly arranged on the bracket and a front-back moving assembly arranged on the left-right moving assembly, and the laser cutting head is arranged on the front-back moving assembly.
[0016] With the above solution, the cutting path of the laser cutting head is controlled by moving the components.
[0017] Furthermore, a dustproof net is provided at the adsorption hole.
[0018] By adopting the above solution, a dustproof net is provided to prevent dust from entering the adsorption tube.
[0019] Furthermore, a vacuum check valve is provided at the adsorption hole, and the vacuum check valve includes a first cavity, a second cavity provided below the first cavity, a valve shaft slidably provided in the second cavity, a valve cover provided at the upper end of the valve shaft, and a spring provided on the valve shaft, the diameter of the first cavity is greater than the diameter of the second cavity, and the length of the valve shaft is greater than the depth of the second cavity; when the adsorption hole does not contact the substrate, the valve cover moves downward under the action of vacuum suction to close the second cavity, thereby reducing the weakening of the adsorption force.
[0020] By adopting the above scheme, by setting a vacuum check valve, when some adsorption tubes are not covered with substrates, the vacuum check valve is closed to reduce the weakening of vacuum suction and avoid the situation where the substrate is not firmly adsorbed and fixed due to air pressure leakage.
[0021] Furthermore, a connecting pipe is provided at the lower end of the adsorption tube, and the connecting pipe is connected to the vacuum pipe.
[0022] By adopting the above scheme, a connecting pipe is provided, the connecting pipe is connected to a flexible vacuum pipe, and multiple vacuum pipes are connected to a main pipe, and the main pipe is connected to a vacuum pump to provide negative pressure for multiple adsorption tubes.
[0023] Another aspect of the present invention provides a high-strength and high-thermal-conductivity silicon nitride ceramic substrate, which is obtained by a preparation process of the high-strength and high-thermal-conductivity silicon nitride ceramic substrate.
[0024] Beneficial effects of the present invention: The vacuum adsorption platform is divided into several movable adsorption tubes, and the position of the adsorption tubes is adjusted by sliding the adsorption tubes on slide bars 1 and 2, so that the cutting path corresponds to the gaps between the several adsorption tubes. When cutting the substrate, the laser cutting head can completely penetrate the substrate, avoiding the reserved depth during cutting, and then the substrate is divided by a dividing device, which simplifies the dividing process, improves the flatness of the edge of the substrate after division, and avoids secondary separation processing to cause rough cross-section.
[0025] By setting the vacuum check valve, when some adsorption tubes are not covered with substrates, the vacuum check valve is closed, reducing the weakening of vacuum suction and avoiding the situation where the substrate is not firmly adsorbed and fixed due to air pressure leakage. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Figure 1 A three-dimensional diagram of a cutting device in the process for preparing a high-strength and high-thermal-conductivity silicon nitride ceramic substrate according to the present invention; Figure 2 A top view of a cutting device in the process for preparing a high-strength and high-thermal-conductivity silicon nitride ceramic substrate according to the present invention; Figure 3 for Figure 1 A stereogram without moving components; Figure 4 for Figure 2 A top view without moving components; Figure 5 It is a stereoscopic diagram of the left and right sliding components and the front and rear sliding components of the cutting device in the process for preparing the high-strength and high-thermal-conductivity silicon nitride ceramic substrate of the present invention; Figure 6 It is a plan view of the front and rear sliding components of the cutting device in the process for preparing the high-strength and high-thermal-conductivity silicon nitride ceramic substrate of the present invention; Figure 7 It is a plan view of the left and right sliding components of the cutting device in the process for preparing the high-strength and high-thermal-conductivity silicon nitride ceramic substrate of the present invention; Figure 8 A stereoscopic diagram of an adsorption tube of a cutting device in the process for preparing a high-strength and high-thermal-conductivity silicon nitride ceramic substrate of the present invention; Fig. 9 For the present invention Figure 8 Top view; Fig.10 For the present invention Fig. 9 Sectional view at AA; Fig.11 This is a diagram showing the position change of the adsorption tube of the cutting device in the process for preparing the high-strength and high-thermal-conductivity silicon nitride ceramic substrate of the present invention.
[0027] In the figure: 1. Bracket; 2. Moving assembly; 3. Laser cutting head; 4. Adsorption tube; 5. Through hole 1; 6. Through hole 2; 7. Slide rod 1; 8. Slide rod 2; 9. Left and right sliding assembly; 10. Front and back sliding assembly; 11. Support plate 1; 12. Slide groove 1; 13. Connecting rod 1; 14. Connecting plate 1; 15. Motor 1; 16. Threaded shaft 1; 17. Support plate 2; 18. Slide groove 2; 19. Connecting rod 2; 20. Connecting plate 2; 21. Motor 2; 22. Threaded shaft 2; 23. Left and right moving assembly; 24. Front and back moving assembly; 25. Dustproof net; 26. Vacuum check valve; 27. First cavity; 28. Second cavity; 29. Valve shaft; 30. Valve cover; 31. Spring; 32. Connecting pipe. DETAILED DESCRIPTION
[0028] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.
[0029] Reference Figure 1-11, which is an embodiment of the present invention, provides a process for preparing a high-strength and high-thermal-conductivity silicon nitride ceramic substrate, comprising a first step of mixing silicon nitride powder, a sintering aid, carbon black, triethyl phosphate and a solvent by ball milling; a second step of adding polyvinyl butyral and polyethylene glycol after the first mixing, and mixing them for a second time by ball milling to obtain a slurry; The third step is to pour the slurry into a container and place it in a vacuum degassing machine for degassing treatment; the fourth step is to prepare a thin sheet of green blank by a tape casting method using the degassing slurry; the fifth step is to place the thin sheet of green blank in a debinding furnace for debinding treatment; the sixth step is to place the debinding green blank in a high-temperature sintering furnace for sintering to obtain a silicon nitride ceramic substrate; the seventh step is to place the cooled ceramic substrate on a cutting device to cut the ceramic substrate into blocks; the eighth step is to place the cut ceramic substrate in a grinding device for grinding to remove burrs and broken edges after cutting.
[0030] By adding carbon black to the raw material ratio and adopting a two-step heating and sintering process, the carbon black and the oxygen impurities in silicon nitride can fully react chemically under appropriate temperature and atmosphere conditions, effectively reducing the lattice oxygen content of the silicon nitride ceramic, thereby improving its thermal conductivity, and making the prepared silicon nitride ceramic substrate have excellent properties of high thermal conductivity and high bending strength.
[0031] Reference Figure 1-8 The cutting device includes a bracket 1, a moving component 2 arranged on the bracket 1, a laser cutting head 3 arranged on the moving component 2, a plurality of adsorption tubes 4 arrayed in the bracket 1, through holes 1 5 and through holes 2 6 respectively arranged on the plurality of adsorption tubes 4, the through holes 1 5 are arranged along the front-to-back direction, and the through holes 2 6 are arranged along the left-to-right direction, and also includes a plurality of sliding rods 1 7 penetrating the plurality of through holes 1 5 and a plurality of sliding rods 2 8 penetrating the plurality of through holes 2 6, the plurality of sliding rods 1 7 are provided with left-right sliding components 9 for controlling the plurality of sliding rods 1 7 to slide in the left-to-right direction, the plurality of sliding rods 2 8 are provided with front-to-back sliding components 10 for controlling the plurality of sliding rods 2 8 to slide in the front-to-back direction, the hole walls of the through holes 1 5 and the through holes 2 6 are not connected to the inner cavity of the adsorption tube 4, the upper end of the adsorption tube 4 is provided with an adsorption hole, and the lower ends of the plurality of adsorption tubes 4 are connected to the vacuum pump through a flexible pipe.
[0032] Specifically, the adsorption tube 4 is arranged in a 5x7 array. The adsorption tube 4 is a completely closed cavity and is not connected to the through hole 1 5 and the through hole 2 6. An adsorption hole is opened above the adsorption tube 4 to adsorb the substrate, and a flexible vacuum pipeline is connected below. This arrangement is to adapt to the changing position of the adsorption tube 4; further, a laser scribing device can be arranged above the adsorption tube 4 to display the cutting path of the laser, and the cutting path can be placed in the gaps between the adsorption tubes 4 by adjusting the positions of several adsorption tubes 4; at the same time, the cross-section of the adsorption tube 4 can also be circular, triangular, etc. The number and cross-sectional size of the adsorption tube 4 are not fixed and can be adjusted according to the number of substrates to be cut.
[0033] By dividing the vacuum adsorption platform into several movable adsorption tubes 4, the position of the adsorption tube 4 is adjusted by sliding the adsorption tube 4 on the slide bar 1 7 and the slide bar 2 8, so that the cutting path corresponds to the gap between the several adsorption tubes 4, the laser cutting head 3 can completely penetrate the substrate when cutting the substrate, avoiding reserving depth during cutting, and then dividing by a dividing device, which simplifies the dividing process and improves the flatness of the edge of the substrate after dividing.
[0034] Reference Figure 3 and Figure 7 The left and right sliding components 9 include support plates 11 symmetrically arranged on the front and rear sides of the bracket 1, a slide groove 12 horizontally arranged on the support plate 11, and a connecting rod 13 cross-arranged on one side of the slide rod 7. The connecting rods 13 on multiple slide rods 7 are hinged to each other to form a retractable connecting rod mechanism, and also include a connecting plate 14 arranged at the rightmost hinge point of the connecting rod 13, a motor 15 arranged on the support plate 11 on the same side as the connecting rod 13, and a threaded shaft 16 arranged on the main shaft of the motor 15. The threaded shaft 16 is threadedly connected to the connecting plate 14, and the slide rod 7 located in the middle is fixedly connected to the support plate 11, and the other two ends of the slide rod 7 slide in the slide groove 12.
[0035] Specifically, each slide bar 7 is cross-hinged with a pair of connecting rods 13, the centers of the pair of connecting rods 13 are hinged to the slide bar 7, and the pair of slide bars 7 are arranged in an "X" shape. The connecting rods 13 on multiple adjacent slide bars 7 are hinged to each other to form a diamond-shaped telescopic connecting rod mechanism. Since the slide bar 7 located in the middle is fixedly connected to the support plate 11, the motor 15 is started, and the threaded shaft 16 on the motor 15 rotates to push the connecting plate 14 to move. The connecting plate 14 pushes the hinge point of the slide bar 7. When pushing the hinge point at the edge, the slide bars 7 on both sides of the center slide bar 7 will move closer to or away from the center.
[0036] By setting up the left and right sliding components 9, the connecting rod mechanism drives multiple sliding rods 7 to move symmetrically and equidistantly with the central sliding rod 7 as the central axis, thereby driving multiple adsorption tubes 4 to move equidistantly in the left and right directions, so as to adapt to different cutting specifications and cutting paths.
[0037] Reference Figure 3 and Figure 6 The front and rear sliding components 10 include support plates 17 symmetrically arranged on the left and right sides of the bracket 1, slide grooves 18 horizontally arranged on the support plates 17, and connecting rods 19 cross-arranged on one side of the slide rods 8. The connecting rods 19 on multiple slide rods 8 are hinged to each other to form a retractable connecting rod mechanism, and also include a connecting plate 20 arranged at the rightmost hinge point of the connecting rods 19, a motor 21 arranged on the support plate 17 on the same side as the connecting rods 19, and a threaded shaft 22 arranged on the main shaft of the motor 21. The threaded shaft 22 is threadedly connected to the connecting plate 20, the slide rod 8 located in the middle is fixedly connected to the support plate 17, and the other two ends of the slide rods 8 slide in the slide grooves 18.
[0038] Specifically, similarly, the front and rear sliding components 10 and the left and right sliding components 9 are set in the same principle. The motor 21 is started, and the threaded shaft 22 on the motor 21 rotates, pushing the connecting plate 20 to move, and the connecting plate 20 pushes the hinge point of the slide bar 28. When the hinge point at the edge is pushed, the slide bars 28 on both sides of the center slide bar 28 will move closer to or away from the center. By setting the front and rear sliding components 10, the connecting rod mechanism drives multiple sliding rods 8 to move symmetrically and equidistantly with the center sliding rod 8 as the central axis, thereby driving multiple adsorption tubes 4 to move equidistantly in the front and rear directions, so as to adapt to different cutting specifications and cutting paths.
[0039] Reference Figure 1 The moving assembly 2 includes a left-right moving assembly 232 arranged on the bracket 1 and a front-back moving assembly 242 arranged on the left-right moving assembly 232 , and the laser cutting head 3 is arranged on the front-back moving assembly 242 .
[0040] The cutting path of the laser cutting head 3 is controlled by the moving assembly 2 .
[0041] Reference Figure 8 A dustproof net 25 is provided at the adsorption hole.
[0042] The dustproof net 25 is provided to prevent dust from entering the adsorption tube 4 .
[0043] Reference Figure 8-10A vacuum check valve 26 is provided at the adsorption hole, and the vacuum check valve 26 includes a first cavity 27, a second cavity 28 provided below the first cavity 27, a valve shaft 29 slidably provided in the second cavity 28, a valve cover 30 provided at the upper end of the valve shaft 29, and a spring 31 provided on the valve shaft 29. The diameter of the first cavity 27 is greater than the diameter of the second cavity 28, and the length of the valve shaft 29 is greater than the depth of the second cavity 28. When the adsorption hole does not contact the substrate, the valve cover 30 moves downward under the action of vacuum suction to close the second cavity 28, thereby reducing the weakening of the adsorption force.
[0044] Specifically, the vacuum check valve 26 is arranged at the adsorption hole of the adsorption tube 4 and is located below the dustproof net 25. The valve body is connected from top to bottom. There is a piston composed of a valve shaft 29, a valve cover 30 and a spring 31 in the valve body. When the adsorption hole is covered with a substrate, the adsorption force mainly acts on the bottom of the substrate, the valve cover 30 is not affected, and the piston is in an open state; when the adsorption hole is not covered with a substrate, the adsorption force mainly acts on the valve cover 30, and the piston is in a closed state, thereby reducing the weakening of the vacuum suction force.
[0045] By providing the vacuum check valve 26 , when some adsorption tubes 4 are not covered with substrates, the vacuum check valve 26 is closed, so as to reduce the weakening of vacuum suction and avoid the situation that the substrate is not firmly adsorbed and fixed due to air pressure leakage.
[0046] Reference Figure 8 A connecting pipe 32 is provided at the lower end of the adsorption tube 4, and the connecting pipe 32 is connected to the vacuum pipeline.
[0047] By setting a connecting pipe 32 , the connecting pipe 32 is connected to a flexible vacuum pipe, and multiple vacuum pipes are connected to a main pipe, and the main pipe is connected to a vacuum pump to provide negative pressure for multiple adsorption tubes 4 .
[0048] The present invention also provides a high-strength and high-thermal-conductivity silicon nitride ceramic substrate, which is prepared by adopting a high-strength and high-thermal-conductivity silicon nitride ceramic substrate preparation process.
[0049] Working principle of the present invention: When it is necessary to cut the ceramic substrate, firstly, the cutting path is projected onto the adsorption tube 4 through the laser scribing device to display the cutting path of the laser, and the positions of several adsorption tubes 4 are adjusted to make the cutting path in the gaps of several adsorption tubes 4; then, the motor 15 is started, and the threaded shaft 16 on the motor 15 rotates to push the connecting plate 14 to move, and the connecting plate 14 pushes the hinge point of the slide bar 7. When pushing the hinge point of the edge, the slide bars 17 on both sides of the center slide bar 7 will move toward or away from the center, so that the slide bar 17 drives the adsorption tubes 4 on both sides of the center adsorption tube 4 to move toward or away from the center in the left and right directions, so that the gaps of the multiple adsorption tubes 4 in the front and back directions match the cutting path; similarly, through the motor 21, the gaps of the multiple adsorption tubes 4 in the left and right directions match the cutting path (such as Figure 4 and Fig.11 As shown, the position of the adsorption tube is changed); when the cutting path is completely in the gap between the adsorption tubes 4, the ceramic substrate is placed on the upper surface of the adsorption tube 4, the vacuum pump is started to adsorb the substrate, and then the laser cutting head 3 is started for cutting.
[0050] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.
Claims
1. A process for preparing a high-strength and high-thermal-conductivity silicon nitride ceramic substrate. It is characterized in that The following steps are involved: In the first step, silicon nitride powder, sintering aid, carbon black, triethyl phosphate and solvent are mixed for the first time by ball milling; In the second step, after the first mixing, polyvinyl butyral and polyethylene glycol are added, and the mixture is mixed for the second time by ball milling to obtain a slurry; The third step is to pour the slurry into a container and place it in a vacuum degassing machine for degassing; The fourth step is to prepare a thin sheet green blank by tape casting method from the deaerated slurry; the fifth step is to place the thin sheet green blank in a debinding furnace for debinding treatment; Step 6: Place the debinding green blank in a high-temperature sintering furnace for sintering to obtain a silicon nitride ceramic substrate; Step 7: placing the cooled ceramic substrate on a cutting device to cut the ceramic substrate into blocks; In the eighth step, the cut ceramic substrate is placed in a grinding device for grinding to remove burrs and broken edges after cutting.
2. The process for preparing a high-strength and high-thermal-conductivity silicon nitride ceramic substrate according to claim 1, Features: The cutting device comprises a support (1), a moving assembly (2) arranged on the support (1), a laser cutting head (3) arranged on the moving assembly (2), a plurality of adsorption tubes (4) arrayed in the support (1), through holes (5) and through holes (6) respectively arranged on the plurality of adsorption tubes (4), the through holes (5) being arranged along the front-back direction, the through holes (6) being arranged along the left-right direction, and further comprising a plurality of sliding rods (7) penetrating the plurality of through holes (5) and a plurality of sliding rods (7) penetrating the plurality of through holes (6). A plurality of slide bars (8) are provided on each of the slide bars (7), and a left-right sliding assembly (9) is provided on each of the slide bars (7) for controlling the slide bars (7) to slide in the left-right direction; a plurality of slide bars (8) are provided on each of the slide bars (8) for controlling the slide bars (8) to slide in the front-rear direction; the hole walls of the through hole (5) and the through hole (6) are not connected to the inner cavity of the adsorption tube (4); an adsorption hole is provided on the upper end of the adsorption tube (4); and the lower ends of the plurality of adsorption tubes (4) are connected to a vacuum pump via a flexible pipe.
3. The process for preparing a high-strength and high-thermal-conductivity silicon nitride ceramic substrate according to claim 2, Features: The left and right sliding assembly (9) comprises a support plate (11) symmetrically arranged on the front and rear sides of the bracket (1), a slide groove (12) horizontally arranged on the support plate (11), and a connecting rod (13) cross-arranged on one side of the sliding rod (7). The connecting rods (13) on the plurality of sliding rods (7) are hinged to each other to form a retractable connecting rod mechanism, and also comprises a connecting plate (14) arranged at the rightmost hinge point of the connecting rod (13), a motor (15) arranged on the support plate (11) on the same side as the connecting rod (13), and a threaded shaft (16) arranged on the main shaft of the motor (15). The threaded shaft (16) is threadedly connected to the connecting plate (14), the sliding rod (7) located in the middle is fixedly connected to the support plate (11), and the two ends of the remaining sliding rods (7) slide in the slide groove (12).
4. The process for preparing a high-strength and high-thermal-conductivity silicon nitride ceramic substrate according to claim 3, Features: The front and rear sliding assembly (10) comprises a supporting plate (17) symmetrically arranged on the left and right sides of the bracket (1), a sliding groove (18) horizontally arranged on the supporting plate (17), and a connecting rod (19) cross-arranged on one side of the sliding rod (8). The connecting rods (19) on a plurality of sliding rods (8) are hinged to each other to form a retractable connecting rod mechanism. The front and rear sliding assembly (10) also comprises a connecting plate (20) arranged at the rightmost hinge point of the connecting rod (19), a motor (21) arranged on the supporting plate (17) on the same side as the connecting rod (19), and a threaded shaft (22) arranged on the main shaft of the motor (21). The threaded shaft (22) is threadedly connected to the connecting plate (20), the sliding rod (8) located in the middle is fixedly connected to the supporting plate (17), and the two ends of the other sliding rods (8) slide in the sliding groove (18).
5. The process for preparing a high-strength and high-thermal-conductivity silicon nitride ceramic substrate according to claim 4, Features: The moving assembly (2) comprises a left-right moving assembly (23) arranged on the bracket (1) and a front-back moving assembly (24) arranged on the left-right moving assembly (23); the laser cutting head (3) is arranged on the front-back moving assembly (24).
6. The process for preparing a high-strength and high-thermal-conductivity silicon nitride ceramic substrate according to claim 2, Features: A dustproof net (25) is provided at the adsorption hole.
7. The process for preparing a high-strength and high-thermal-conductivity silicon nitride ceramic substrate according to claim 2, Features: A vacuum check valve (26) is arranged at the adsorption hole, and the vacuum check valve (26) comprises a first cavity (27), a second cavity (28) arranged below the first cavity (27), a valve shaft (29) slidably arranged in the second cavity (28), a valve cover (30) arranged at the upper end of the valve shaft (29), and a spring (31) arranged on the valve shaft (29), wherein the diameter of the first cavity (27) is greater than the diameter of the second cavity (28), and the length of the valve shaft (29) is greater than the depth of the second cavity (28); when the adsorption hole does not contact the substrate, the valve cover (30) moves downward under the action of vacuum suction to close the second cavity (28), thereby reducing the weakening of the adsorption force.
8. The process for preparing a high-strength and high-thermal-conductivity silicon nitride ceramic substrate according to claim 2, Features: A connecting pipe (32) is provided at the lower end of the adsorption tube (4), and the connecting pipe (32) is connected to the vacuum pipeline.
9. A high-strength and high-thermal-conductivity silicon nitride ceramic substrate, prepared by the high-strength and high-thermal-conductivity silicon nitride ceramic substrate preparation process according to any one of claims 1 to 8.