A DBC substrate surface treatment system and method based on plasma jet array

Abstract

The application discloses a kind of DBC substrate surface treatment system and method based on plasma jet array, belong to surface treatment field, system includes plasma jet array, power device and gas source device;Plasma jet array includes three jet units arranged in sequence;Each jet unit is connected with gas source device and power device;Gas source device includes inert gas storage tank, air storage tank and reaction medium storage tank respectively connected with three jet units, three jet units generate jet body for cleaning, oxidation modification and film deposition on the surface of DBC substrate respectively when working;Reaction medium is methoxysilane, titanium tetrachloride or carbon tetrafluoride, so that the dielectric parameters of the deposited film on the surface of DBC substrate are optimized to improve electrical strength.The application not only can improve the electrical strength of DBC substrate surface, but also has the characteristics of low waste discharge, low energy loss, suitable for flow line operation.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a DBC substrate surface treatment system and method based on a plasma jet array. Background Art

[0002] High-voltage power semiconductor devices are the core of various high-voltage, large-capacity power conversion and control equipment. They have become the foundational components supporting the development of high-voltage direct current (HVDC) grids, high-speed railways, and avionics power supply units. However, due to limitations in packaging and insulation technology, the operating voltage and operating temperature of high-voltage power semiconductor devices are far below the limit parameters of wide-bandgap semiconductor materials. In particular, the insulation structure of the copper-clad ceramic substrate (DBC) of high-voltage power modules, where the metal electrode, ceramic substrate, and potted insulation form a typical "three-solid" insulation structure, can cause local electric field concentration due to the mismatch of interface dielectric parameters. This can easily trigger partial discharge, which in turn causes insulation aging and insulation breakdown, leading to power device failure.

[0003] To address the problem of electric field concentration at the inner interface of the insulation of high-voltage power module packaging, scholars and industry practitioners have tried to improve the electric field distribution by regulating the insulation geometry, but the improvement effect is limited by the constraints of the device structure size. Some have also tried to obtain nonlinear insulating materials through filler modification to achieve flexible equalization of the electric field, but this "interference" material modification method faces problems such as complex process and high cost.

[0004] Therefore, in order to address the typical interface problem of "triple junctions", a surface treatment method is currently needed to homogenize the electric field on the surface of the DBC substrate and improve its electrical insulation performance; at the same time, the surface treatment method also needs to have high processing efficiency and low resource and energy consumption to meet the high requirements of semiconductor chip assembly line production on processing efficiency and production costs.

[0005] As a new material surface treatment method, atmospheric pressure low-temperature plasma technology can use plasma to induce physical and chemical reactions on the material surface under mild conditions without destroying the properties of the substrate, thereby achieving the polymerization, grafting copolymerization and modification of target monomer molecules, thereby controllably changing the physical and chemical properties of the material surface. In particular, the plasma-enhanced chemical vapor deposition method for depositing passivation layer films to improve the physical, chemical, mechanical and electrical properties of insulation has received widespread attention. For example, some researchers have used plasma to construct a dense network film on the surface of epoxy resin to improve its hydrophobicity, or used plasma to treat organic glass insulation to introduce fluorine-containing groups (-CFn, -CHnF) to increase the flashover voltage of the material surface. It can be seen that low-temperature plasma technology has unique advantages in terms of physical morphology and structure of material surfaces, chemical grafting and bonding, and surface performance optimization.

[0006] Plasma jets, as a typical form of plasma generation, are very suitable for treating the surfaces of complex structural materials because their discharge space is separated from the plasma space. However, plasma jets generally have a needle-like or tubular structure and are only suitable for treating special locations with extremely small areas. Currently, multiple jet units are often used to form a plasma jet array mode to achieve the treatment of large-area material surfaces. For example, some scholars have used dozens of single jet units arranged in parallel and honeycomb to form one-dimensional and two-dimensional jet arrays, generating large-area plasma discharges with a width of 3.2 cm and an area of ​​18.6 cm2, respectively.

[0007] For example, Chinese invention patent publication number CN110831343A discloses a surface treatment method for selective electroless silver deposition on DBC substrates. This patent utilizes a secondary dry film to reveal areas where silver deposition is required. By opening windows during secondary dry film exposure, controlling the thickness of the deposited silver, and performing post-electroless silver cleaning, the patent addresses issues such as DBC surface contamination, copper surface oxidation, and silver layer shedding. While this patented method deposits metallic silver and improves the intrinsic structure of the DBC, enhancing its material stability, it fails to address the issue of electric field concentration at the interface between the metal and ceramic substrate.

[0008] For example, Chinese invention patent publication number CN102560488A discloses a surface treatment process for ceramic-copper bonded substrates using nanosilver solder paste to connect chips. The process involves pre-cleaning the DBC substrate, electroplating it with nickel, and then magnetron sputtering it with silver to prevent copper from seeping out of the silver layer and ensure good bonding strength. This method improves the material properties of DBC substrates through chemical process optimization, but the large amount of chemicals used results in significant environmental and resource waste, and it also fails to meet the demand for improved surface properties of DBC substrates.

[0009] For example, Chinese invention patent publication number CN104624138A discloses a device and method for uniformly treating aqueous solutions with a plasma jet array. The device utilizes four plasma jets to form a jet array, achieving large-area aqueous solution treatment. While the patent utilizes the plasma jet array solely to increase the plasma treatment area, the four plasma jets have identical structures and operating conditions and lack the ability to functionally couple the material surface.

[0010] For example, Chinese invention patent publication number CN110054181A discloses a method and apparatus for surface modification of graphene oxide. The method utilizes a honeycomb array of seven essentially atmospheric-pressure plasma jet units to generate a room-temperature, large-area, non-equilibrium discharge plasma, effectively treating the surface of large graphene oxide surfaces. However, the jet unit structure is identical, and neither possesses the functional coupling capability for treating the material surface. Furthermore, the method is unsuitable for efficient and multifunctional sample processing on an assembly line.

[0011] In summary, current surface treatments for DBC substrates primarily address inherent issues such as unstable material properties and weak interfacial bonding. Surface treatment of DBC materials, particularly at the "triple junctions," has not been addressed, and there is a lack of research focused on improving DBC electrical insulation performance. Furthermore, most surface treatment methods rely on chemical reagents, which present disadvantages such as harsh reaction conditions, wastewater contamination, and resource loss, making them difficult to directly incorporate into DBC substrate production lines. While plasma jet arrays have been used in material surface modification, current efforts primarily focus on improving discharge area and uniformity, failing to achieve functional coupling with the material and making them unsuitable for industrial, continuous processing of large quantities of DBC substrates. Summary of the Invention

[0012] In view of the problem that the existing systems and methods in the prior art cannot achieve high-efficiency, low-pollution, multifunctional and continuous surface treatment of DBC substrates, the purpose of the present invention is to provide a DBC substrate surface treatment system and method based on a plasma jet array, so as to at least partially solve the above problems.

[0013] To achieve the above object, the technical solution of the present invention is:

[0014] In a first aspect, the present invention provides a DBC substrate surface treatment system based on a plasma jet array, comprising a plasma jet array, a power supply device, and a gas source device; the plasma jet array comprises three jet units arranged in sequence; each of the jet units is connected to the gas source device and the power supply device;

[0015] The gas source device includes an inert gas storage tank, an air storage tank and a reaction medium storage tank respectively connected to the three jet units, so that when the three jet units are in operation, they respectively generate jet plumes for cleaning, oxidative modification and thin film deposition on the surface of the DBC substrate; the reaction medium is methoxysilane, titanium tetrachloride or carbon tetrafluoride, so that the dielectric parameters of the DBC substrate surface are optimized through the deposited thin film to improve the electrical strength.

[0016] In a preferred embodiment, the jet units each include a metal shell and a metal electrode fixed in the metal shell by an insulating support, the metal electrodes are connected to the power supply device, and the metal shells are grounded; one end of the metal shell is closed and provided with a gas inlet, and the other end is open to form a jet outlet, and the insulating support is also provided with a vent hole. The gas inlets of the three jet units are respectively connected to the inert gas, the air, and the reaction medium through gas supply pipes.

[0017] In a preferred embodiment, the three jet units are jet unit A, jet unit B and jet unit C, which are arranged in sequence; wherein, the jet outlets of the jet unit A and the jet unit C are both installed with an annular blocking medium made of insulating material for isolating the metal electrode from the metal shell.

[0018] In a preferred embodiment, in the jet unit B and the jet unit C, a metal needle tip for enhancing the plasma discharge intensity is installed at one end of the metal electrode close to the jet outlet.

[0019] In a preferred embodiment, a blocking block made of insulating material is installed at the jet outlet of the jet unit B and the jet unit C, and a flow microhole for controlling the shape of the jet plume is opened in the blocking block, and the flow microhole is opposite to the metal needle tip.

[0020] In a preferred embodiment, in the jet unit C, the blocking block is fixedly installed in the annular blocking medium.

[0021] In a preferred embodiment, the power supply device is a high-frequency AC power supply device, a microsecond pulse power supply device, or a nanosecond pulse power supply device.

[0022] In a preferred embodiment, a power switch is connected between the power supply device and each of the jet units, and the power switch is electrically connected to a switch controller. The switch controller selectively connects the power supply device and each of the jet units by controlling the state of the power switch; a flow switch is provided on the gas supply pipe connected to the gas inlet in each of the jet units, and each of the flow switches is electrically connected to the flow controller.

[0023] In a preferred embodiment, a conveying device is further included, which is used to convey the DBC substrate. The conveying direction of the conveying device is consistent with the arrangement direction of each jet unit in the plasma jet array, and the conveying device is located on the jet outlet side of each jet unit; wherein, the plasma jet array is also equipped with a position detection device for detecting the position of the DBC substrate, and the position detection device is electrically connected to the switch controller and the flow controller.

[0024] In a second aspect, the present invention further provides a method applied to the above system, comprising the following steps:

[0025] S1. When the position detection device detects that the DBC substrate passes through the jet unit A, the switch controller and the flow controller are activated to connect the jet unit A to the power supply device and the gas source device, causing the jet unit A to generate a jet plume under an inert gas atmosphere, thereby cleaning the surface of the DBC substrate;

[0026] S2. When the position detection device detects that the DBC substrate passes through jet unit B, the switch controller and the flow controller are activated to connect jet unit B to the power supply device and the air source device, causing jet unit B to generate a jet plume in an air atmosphere, thereby oxidizing and modifying the surface of the DBC substrate to improve surface adhesion;

[0027] S3. When the position detection device detects that the DBC substrate passes through the jet unit C, the switch controller and the flow controller are activated to connect the jet unit C to the power supply device and the gas source device separately, so that the jet plume generated by the jet unit C deposits a thin film on the surface of the DBC substrate to optimize the dielectric parameters and improve the electrical strength.

[0028] The beneficial effects of the present invention, employing the above-described technical solution, lie in the following: By employing an array of plasma jet units with distinct functions, the present invention can rapidly and efficiently perform plasma treatment on the surface of DBC substrates in inert gas atmospheres, air atmospheres, and reaction medium atmospheres, respectively, achieving cleaning, oxidation modification, and thin film deposition on the DBC substrate surface. This improves the electric field distribution and dielectric parameters on the DBC substrate surface, thereby increasing its electrical strength and ultimately ensuring the stable operation of the high-voltage power module. Compared to conventional technologies, the present invention not only reduces waste emissions and energy loss but is also suitable for assembly line operations, enabling industrial continuous processing of large quantities of DBC substrates. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 The figure is a schematic structural diagram of a DBC substrate surface treatment system based on a plasma jet array according to the present invention.

[0030] Figure 2 It is a structural schematic diagram of the power supply device in the present invention.

[0031] Figure 3 Schematic diagram of the structure of the gas source device in the present invention.

[0032] In the figure: 1-metal shell, 2-metal electrode, 3-insulating joint, 4-insulating support, 5-annular blocking medium, 6-metal needle tip, 7-blocking block, 8-conveying device, 9-DBC substrate, 10-plasma jet array, 11-support frame, 12-position detection device A, 13-position detection device B, 14-position detection device C, 15-position detection device D, 20-power supply device, 21-excitation source, 22-power switch, 23-switch controller, 30-gas source device, 31-inert gas storage tank, 32-air storage tank, 33-reaction medium storage tank, 34-flow controller, 35-flow switch A, 36-flow switch B, 37-flow switch D. DETAILED DESCRIPTION

[0033] The following is a further description of specific embodiments of the present invention in conjunction with the accompanying drawings. It should be noted that the description of these embodiments is intended to facilitate understanding of the present invention and does not constitute a limitation of the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0034] It should be noted that, in the description of the present invention, the terms "up", "down", "left", "right", "front", "back", etc. indicating directions or positional relationships are based on the description of the structure of the present invention shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, it cannot be understood as a limitation on the present invention.

[0035] The "first" and "second" in this technical solution are only used to distinguish the same or similar structures, or corresponding structures with similar functions, and are not an arrangement of the importance of these structures, nor do they have any ranking, size comparison, or other meanings.

[0036] In addition, unless otherwise expressly specified or limited, the terms "installed" and "connected" should be understood broadly. For example, a connection can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be internal communication between two structures. Those skilled in the art can understand the specific meanings of the above terms in the present invention based on the overall principles of the present invention and the specific context of this solution.

[0037] Example 1

[0038] A DBC substrate surface treatment system based on plasma jet array, such as Figure 1 As shown, it includes a plasma jet array 10 , a power supply device 20 and a gas source device 30 .

[0039] Among them, the plasma jet array 10 includes a support frame 11 and three jet units installed on the support frame 11. The three jet units are arranged vertically and linearly along the first horizontal direction, and are respectively recorded as jet unit A (P1 in the figure), jet unit B (P2 in the figure) and jet unit C (P3 in the figure), and the plasma outlet of each jet unit is arranged downward.

[0040] In this embodiment, fluidic units A, B, and C all share the same basic structure, comprising a metal housing 1 and a metal electrode 2 positioned within the housing. The metal housing 1 is grounded, with a closed top and a central gas inlet, and an open bottom to form a jet outlet. The metal electrode 2 is made of a conductive metal such as copper, aluminum, or stainless steel. The length of the metal electrode 2 is shorter than that of the metal housing 1 and the metal electrode 2 is coaxially arranged in the center of the metal housing 1.

[0041] In addition, an insulating joint 3 is installed on the upper side wall of the metal shell 1, so that the upper end of the metal electrode 2 can be connected to the insulating joint 3 through a wire and then connected to the power supply device 20 through a wire. The power supply device 20 includes an excitation source 21. The excitation source 21 can be specifically configured as a high-frequency AC power supply, a microsecond pulse power supply, or a nanosecond pulse power supply. Usually, a power switch 22 for controlling the on-off state of the current is installed on the wires (H1, H2, and H3 in the figure) connecting the excitation source 21 to each jet unit. In this embodiment, the power switch 22 is specifically configured as a single-pole three-throw switch. The power switch 22 is electrically connected to the switch controller 23. The power switch 22 is controlled by the switch controller 23, thereby respectively realizing the connection between the three wires (H1, H2, and H3) and the power supply device 20; of course, in other preferred embodiments, the power switch 22 can also be a single-pole single-throw switch and one is arranged on each wire (H1, H2, and H3), so as to achieve the same control effect, such as Figure 2 shown.

[0042] The metal electrode 2 is specifically fixed in the metal shell 1 by an insulating support 4, wherein the insulating support 4 is a block structure made of insulating material, for example, a cylindrical structure made of polytetrafluoroethylene, whose outer wall is fixed to the inner wall of the metal shell 1, and a center hole for mounting the metal electrode 2 is provided at the center thereof. At the same time, a vent hole for gas passage is also provided on the insulating support 4. Usually, two insulating supports 4 are configured and symmetrically arranged at the upper and lower positions of the metal electrode 2.

[0043] In this embodiment, the gas source device 30 includes an inert gas storage tank 31 for storing inert gas (such as argon or helium), an air storage tank 32 for storing air, and a reaction medium storage tank 33 for storing a reaction medium. The inert gas storage tank 31, the air storage tank 32, and the reaction medium storage tank 33 are respectively connected to the gas inlet of the jet unit A, the jet unit B, and the jet unit C through gas supply pipes (G1, G2, and G3 in the figure, respectively), and each gas supply pipe is installed with a flow switch (which can be a flow meter or a mass flow meter) for controlling the fluid flow state. That is, there are three flow switches (i.e., flow switch A35, flow switch B36, and flow switch C in the figure) and are respectively installed on the three gas supply pipes (G1, G2, and G3). The flow switches A35, B36, and C are all electrically connected to the flow controller 34 so that the flow (including the on-off state) of the flow switches A35, B36, and C (not shown in the figure) can be controlled by the flow controller 34. Figure 3 shown.

[0044] With this arrangement, the states of the power switch 22 and the flow switches 35 are controlled by the switch controller 23 and the flow controller 34, respectively, so that the jet unit A, jet unit B, and jet unit C operate sequentially. When in operation, jet units A, B, and C respectively generate jet plumes for cleaning, oxidative modification (improving the adhesion of the DBC substrate 9), and thin film deposition on the surface of the DBC substrate 9. The reaction medium can be methoxysilane, titanium tetrachloride, or carbon tetrafluoride. The deposited thin film optimizes the dielectric parameters of the DBC substrate 9 surface to enhance electrical strength. Specifically, under the action of the plasma, the reaction medium fragments and deposits on the DBC substrate 9, forming a thin film. This thin film increases the surface roughness of the material and increases the surface creepage distance of the charge. Furthermore, the thin film changes the surface dielectric parameters of the material, achieving electric field homogenization, thereby enhancing the electrical insulation strength of the DBC substrate 9.

[0045] It can be understood that the gas supply pipe (G3) connected to the jet unit C is also connected to the inert gas storage tank 31, that is, the inert gas storage tank 31 is connected to two gas supply pipes (G1, G3), one of which is connected in series with the reaction medium storage tank 33. The flow switch C is installed downstream of the reaction medium storage tank 33 to control the on-off and flow rate of the reaction medium. In addition, a flow switch D37 is installed between the reaction medium storage tank 33 and the inert gas storage tank 31, which is used to control the flow rate of the inert gas when the jet unit C (P3) is working. Figure 3 shown.

[0046] Example 2

[0047] In this embodiment, an annular blocking medium 5 made of an insulating material, such as quartz glass, resin, polytetrafluoroethylene, etc., is installed at the jet outlet of jet unit A and jet unit C. The annular blocking medium 5 is fixed on the inner wall of the lower end of the metal shell 1, thereby isolating the metal electrode 2 and the metal shell 1 at the jet outlet, thereby preventing the arc that may be generated by plasma discharge from damaging the DBC substrate.

[0048] Example 3

[0049] In this embodiment, in the jet unit B and the jet unit C, a metal needle tip 6 for enhancing the plasma discharge intensity is installed at one end of the metal electrode 2 close to the jet outlet, wherein the metal needle tip 6 is installed in a threaded connection manner.

[0050] Example 4

[0051] In this embodiment, a barrier block 7 made of an insulating material, such as quartz glass, resin, or polytetrafluoroethylene, is installed at the jet outlet of both jet unit B and jet unit C. Micropores are provided in barrier block 7 to control the shape and size of the jet plume, thereby aligning the shape and size of the jet plume with the area to be processed on the DBC substrate. Typically, the micropores are located at the center of barrier block 7 and face the metal needle tip 6 above it.

[0052] For the jet unit C, the blocking block 7 is fixedly mounted at the lower end of the annular blocking medium 5, and the two can be integrally formed. For the jet unit B, the blocking block 7 is fixedly mounted at the lower end of the metal shell 1.

[0053] Example 5

[0054] In this embodiment, a conveying device 8 is also included. The conveying device 8 can be a conveyor belt, which is used to convey the DBC substrate 9. The conveying direction of the conveying device 8 is consistent with the arrangement direction of each jet unit in the plasma jet array 10, and the conveying device 8 is located on one side of the jet outlet of each jet unit and has a certain spacing.

[0055] In addition, a position detection device (such as an industrial camera) for detecting the position of the DBC substrate 9 is also installed on the support frame 11 in the plasma jet array 10, namely, a position detection device A12 installed in front of the jet unit A, a position detection device B13 installed between the jet unit A and the jet unit B, and a position detection device C14 installed between the jet unit B and the jet unit C, and each position detection device is electrically connected to the above-mentioned switch controller 23 and the flow controller 34.

[0056] Such arrangement enables the DBC substrate 9 to pass through the plasma jet array 10 under the transmission action of the conveying device 8, and under the combined action of the position detection device, the power switch 22, the switch controller 23, the flow switch A35, the flow switch B36, the flow switch C, and the flow controller 34, so that the jet unit A, the jet unit B, and the jet unit C can respectively clean, oxidize and modify, and perform thin film deposition treatment on the DBC substrate 9 passing through its jet outlet in turn.

[0057] A position detection device D15 is further installed on the support frame 11 at the downstream side of the jet unit C, which is used to provide a position detection function when the DBC substrate leaves the working area of ​​the plasma jet array 10.

[0058] Example 6

[0059] A method applied to the above system comprises the following steps:

[0060] S1. When the position detection device detects that the DBC substrate passes through the jet unit A, the switch controller and the flow controller are activated, and the jet unit A is connected to the power supply device and the gas source device separately, so that the jet unit A generates a jet plume under an inert gas atmosphere, thereby cleaning the surface of the DBC substrate.

[0061] During the process of conveying the DBC substrate 9 by the conveying device 8, when the position detection device A12 captures the DBC substrate 9, the power supply device 20 begins to operate. Simultaneously, the switch controller 23 controls the power switch 22 to operate, turning on the high-voltage wire (H1), and the jet unit A (P1) begins to operate. Simultaneously, the flow controller 34 controls the flow switch A35 to turn on, and the flow switches B36 and C to turn off, thereby allowing the working gas in the inert gas tank 31 to enter the jet unit A (P1) through the gas supply pipe (G1). Plasma is blown out of its jet outlet to generate a jet plume, thereby cleaning the surface of the DBC substrate 9. The presence of the annular barrier medium 5 at the lower end of the jet unit A (P1) effectively prevents arc damage to the DBC substrate 9 caused by the plasma discharge.

[0062] S2. When the position detection device detects that the DBC substrate passes through jet unit B, the switch controller and flow controller are activated, and jet unit B is connected to the power supply device and air source device separately, so that jet unit B generates a jet plume in an air atmosphere, thereby oxidizing and modifying the surface of the DBC substrate to improve surface adhesion.

[0063] The conveying device 8 continues to transport the DBC substrate 9, and when the position detection device B13 captures the DBC substrate 9, the switch controller 23 controls the power switch 22 to operate and turns on the high-voltage wire (H2), the jet unit B (P2) is powered on and starts working, and the jet unit A (P1) loses power and stops working; at the same time, the flow controller 34 controls the flow switch B36 to turn on, the flow switch A35 and the flow switch C to turn off, so that the working gas (air) in the air storage tank 32 is passed into the jet unit B (P2) through the gas supply pipe (G2), thereby blowing out plasma at its jet outlet to generate a jet plume, which is blown out after passing through the flow micropores on the blocking block 7, and can perform oxidation modification treatment on the surface of the DBC substrate 9.

[0064] The metal tip 6 mounted at the lower end of the metal electrode 2 in jet unit B (P2) enhances the plasma discharge intensity. Furthermore, the barrier block 7 and the micropores therethrough ensure strong plasma discharge while controlling the plasma morphology, generating a jet plume tailored to the dimensions of the DBC substrate 9 to be treated, achieving precise treatment of the DBC substrate 9. Because the gas stored in air tank 32 is air, jet unit B (P2) generates an air-atmosphere plasma, oxidatively modifying the surface of the DBC substrate 9 and improving the material's surface adhesion.

[0065] S3. When the position detection device detects that the DBC substrate passes through the jet unit C, the switch controller and the flow controller are activated, and the jet unit C is connected to the power supply device and the gas source device separately, so that the jet plume generated by the jet unit C deposits a thin film on the surface of the DBC substrate to optimize the dielectric parameters and improve the electrical strength.

[0066] The conveying device 8 continues to transport the DBC substrate 9, and when the position detection device C14 captures the DBC substrate 9, the switch controller 23 controls the power switch 22 to operate and turns on the high-voltage wire (H3), so that the jet unit C (P3) is powered on and starts working, while the jet unit B (P2) loses power and stops working. At the same time, the flow controller 34 controls the flow switch C to be turned on, and the flow switches A35 and B36 to be turned off, so that the reaction medium (silicon-containing medium methoxysilane or titanium-containing medium titanium tetrachloride) in the air storage tank 33 is introduced into the jet unit C (P3) through the air supply pipe (G3), thereby blowing out plasma from its jet outlet to generate a jet plume. The jet plume passes through the flow micropores on the blocking block 7 and is blown out, thereby being able to deposit a thin film on the surface of the DBC substrate 9. The deposited thin film can optimize the dielectric parameters of the surface of the DBC substrate 9, thereby improving the electrical strength.

[0067] Among them, since the metal electrode 2 in the jet unit C (P3) is equipped with a metal needle tip 6 at the lower end, the plasma discharge intensity can be enhanced; the presence of the annular blocking medium 5 at the lower end of the jet unit C (P3) can effectively prevent the arc generated by the plasma discharge from causing damage to the DBC substrate 9; the setting of the blocking block 7 at the lower end of the annular blocking medium 5 and the flow micropores thereon can control the morphology of the plasma while ensuring a strong plasma discharge, generate a jet plume that matches the size of the area to be processed of the DBC substrate 9, and realize precise processing of the DBC substrate 9.

[0068] S4. When the position detection device D15 detects the DBC substrate 9, the switch controller 23 and the flow controller 34 are activated to disconnect the jet unit C (P3) from the power supply device 20 and the air source device 30.

[0069] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the described embodiments. It is apparent to those skilled in the art that various changes, modifications, substitutions, and variations to these embodiments may be made without departing from the principles and spirit of the present invention, and these changes and modifications still fall within the scope of protection of the present invention.

Claims

1. A DBC substrate surface treatment system based on a plasma jet array, characterized by: It includes a plasma jet array, a power supply device and a gas source device; the plasma jet array includes three jet units arranged in sequence, namely, jet unit A, jet unit B and jet unit C; in; Each of the jet units is connected to the air source device and the power supply device; The gas source device includes an inert gas storage tank, an air storage tank and a reaction medium storage tank. The jet unit A is connected to the inert gas storage tank, the jet unit B is connected to the air storage tank, and the jet unit C is connected to the inert gas storage tank and the reaction medium storage tank, so that the jet unit A, the jet unit B and the jet unit C respectively generate jet plumes for cleaning, oxidative modification and thin film deposition on the surface of the DBC substrate when in operation; the reaction medium is methoxysilane, titanium tetrachloride or carbon tetrafluoride, so that the dielectric parameters of the DBC substrate surface are optimized by the deposited thin film to improve the electrical strength.

2. The system according to claim 1, wherein: Each of the jet units includes a metal shell and a metal electrode fixed in the metal shell by an insulating support. The metal electrodes are connected to the power supply device, and the metal shells are grounded. One end of the metal shell is closed and provided with a gas inlet, and the other end is open to form a jet outlet. The insulating support is also provided with a vent. The gas inlets of the three jet units are respectively connected to the inert gas, the air, and the reaction medium through gas supply pipes.

3. The system according to claim 2, characterized in that: An annular blocking medium made of insulating material is installed at the jet outlet of the jet unit A and the jet unit C for isolating the metal electrode from the metal shell.

4. The system according to claim 3, wherein: In the jet unit B and the jet unit C, a metal needle tip for enhancing the plasma discharge intensity is installed at one end of the metal electrode close to the jet outlet.

5. The system according to claim 4, characterized in that: The jet outlets of the jet unit B and the jet unit C are both equipped with blocking blocks made of insulating material, and the blocking blocks are provided with flow micropores for controlling the shape of the jet plume, and the flow micropores are directly facing the metal needle tip.

6. The system according to claim 5, characterized in that: In the jet unit C, the blocking block is fixedly installed in the annular blocking medium.

7. The system according to claim 1, wherein: The power supply device is a high-frequency AC power supply device, a microsecond pulse power supply device or a nanosecond pulse power supply device.

8. The system according to claim 1, wherein: A power switch is connected between the power supply device and each of the jet units, and the power switch is electrically connected to a switch controller. The switch controller selectively connects the power supply device and each of the jet units by controlling the state of the power switch; a flow switch is provided on the gas supply pipe connected to the gas inlet in each of the jet units, and each of the flow switches is electrically connected to the flow controller.

9. The system according to claim 8, characterized in that: It also includes a conveying device, which is used to convey the DBC substrate. The conveying direction of the conveying device is consistent with the arrangement direction of each jet unit in the plasma jet array, and the conveying device is located on one side of the jet outlet of each jet unit; wherein, the plasma jet array is also equipped with a position detection device for detecting the position of the DBC substrate, and the position detection device is electrically connected to the switch controller and the flow controller.

10. A method applied to the system according to claim 9, characterized in that: The following steps are involved: S1. When the position detection device detects that the DBC substrate passes through jet unit A, the switch controller and the flow controller are activated to connect jet unit A to the power supply device and the inert gas storage tank in the gas source device, causing jet unit A to generate a jet plume under an inert gas atmosphere, thereby cleaning the surface of the DBC substrate; S2. When the position detection device detects that the DBC substrate passes through the jet unit B, the switch controller and the flow controller are activated to connect the jet unit B to the power supply device and the air storage tank in the air source device, causing the jet unit B to generate a jet plume in an air atmosphere, thereby oxidizing and modifying the surface of the DBC substrate to improve surface adhesion; S3. When the position detection device detects that the DBC substrate passes through the jet unit C, the switch controller and the flow controller are activated to connect the jet unit C to the power supply device and the inert gas storage tank and the reaction medium storage tank in the gas source device separately, so that the jet plume generated by the jet unit C deposits a thin film on the surface of the DBC substrate to optimize the dielectric parameters and improve the electrical strength.

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