Substrate printing process of 200W high-frequency load sheet and 200W high-frequency load sheet

Abstract

The invention relates to a substrate printing process of a 200W high-frequency load sheet and the 200W high-frequency load sheet, and belongs to the technical field of printed circuits. The substrate printing process mainly comprises the following steps: printing a bonding pad, a first conductor, a second conductor and a grounding wire on the front surface of a substrate by using conductive paste; printing the whole back surface of the substrate with conductive paste to obtain a back conductor; printing the left side surface, the right side surface and the lower side surface of the substrate for three times by using conductive paste to obtain a conductor to communicate a grounding wire with a back conductor; printing resistance paste on the front surface of the substrate for at least three times; first printing and second printing are carried out at least once, a first resistive film of a group of series-parallel resistive film networks is obtained through the first printing, and a second resistive film and a third resistive film of a group of series-parallel resistive film networks are obtained through the second printing at the same time; and printing for the third time to obtain a single resistive film. According to the invention, the use frequency is improved while the load can bear high power.

Description

Technical Field

[0001] The present application relates to the technical field of printed circuits, and in particular to a substrate printing process for a 200W high-frequency load sheet and a 200W high-frequency load sheet. Background Art

[0002] At present, due to the limitation of printing process, the load slices with traditional single resistor film printed structure need laser resistance adjustment to have the set characteristics, such as frequency, impedance matching, etc. However, the implementation of laser resistance adjustment destroys the continuity of the whole resistor film, resulting in the following technical barriers in the preparation of current load slices that are difficult to break through: if it can withstand high power, it cannot reach high frequency, and if it can reach high frequency, it can only withstand lower power.

[0003] Therefore, it is urgent to improve the traditional single resistor film printing structure and avoid the use of laser resistance adjustment to overcome the technical barriers existing in the preparation of the above-mentioned load sheet. Summary of the invention

[0004] In view of this, the embodiments of the present application provide a substrate printing process for a 200W high-frequency load sheet and a 200W high-frequency load sheet to solve at least one problem existing in the background technology.

[0005] In a first aspect, an embodiment of the present application provides a substrate printing process for a 200W high-frequency load sheet, comprising: On the front side of the substrate, a conductive paste is used to print a pad, a first conductor, a second conductor and a ground wire; after printing, the conductive paste is dried at 100°C to 150°C, and then sintered at a high temperature of 830°C to 880°C to firmly bond the conductive paste to the substrate; On the reverse side of the substrate, the entire surface is printed with conductive paste to obtain a back conductor; after printing, it is dried at 100°C to 150°C, and then sintered at a high temperature of 830°C to 880°C to firmly bond the conductive paste to the substrate; Conductive paste is printed three times on the left side, right side and bottom side of the substrate, and one of the left side, right side and bottom side is printed each time to obtain a conductor to connect the ground wire and the back conductor; after each printing, it is dried at 100°C to 150°C, and then sintered at a high temperature of 830°C to 880°C to firmly bond the conductive paste to the substrate; On the front side of the substrate, the resistor paste is printed at least three times; at least one first printing and second printing are performed, the first printing obtains a first resistor film of a series-parallel resistor film network, the second printing simultaneously obtains a second resistor film and a third resistor film of a series-parallel resistor film network; the third printing obtains a single resistor film; after each printing, the resistor paste is dried at 100°C to 150°C, and then sintered at a high temperature of 830°C to 880°C to solidify the resistor paste and show resistance value characteristics; Among them, the load sheet includes a single resistor film, and at least one group of series-parallel resistor film networks connected in series at the front end of the single resistor film to form a series-parallel printed structure of multiple resistor films; the first end of the single resistor film is electrically connected to the input end of the load sheet through at least one group of series-parallel resistor film networks, and the first end of the single resistor film and the input end form a first connection direction between each other; the first resistor film and the second resistor film form a second connection direction between each other; the first resistor film and the third resistor film form a third connection direction between each other; the second connection direction and the third connection direction intersect with the first connection direction respectively.

[0006] In a second aspect, an embodiment of the present application provides a 200W high-frequency load sheet, the load sheet comprising: a single resistor film; and at least one group of series-parallel resistor film networks connected in series at the front end of the single resistor film to form a series-parallel printed structure of multiple resistor films; The first end of the single resistor film is electrically connected to the input end through at least one set of series-parallel resistor film networks, and the second end of the single resistor film is grounded to achieve load matching; the first end of the single resistor film and the input end form a first connection direction with each other; The printed series-parallel resistor film network includes a first resistor film, a second resistor film and a third resistor film that are electrically connected; the first resistor film is printed in the first connection direction and is electrically connected between the input end and the first end of the single resistor film, the second resistor film and the third resistor film are respectively printed on both sides of the first resistor film and are grounded respectively; the first resistor film and the second resistor film form a second connection direction between each other; the first resistor film and the third resistor film form a third connection direction between each other; the second connection direction and the third connection direction intersect with the first connection direction respectively; the series-parallel resistor film network is used to attenuate the input signal received by the input end.

[0007] In conjunction with the second aspect, in an optional implementation, The lengths of the connection points of the first resistance film, the second resistance film and the third resistance film along the first connection line direction are equal; And / or, the second connection direction and the third connection direction are parallel or overlapped, and the second resistance film and the third resistance film have the same area.

[0008] In conjunction with the second aspect, in an optional implementation, The load sheet further comprises: a substrate; The single resistor film and at least one group of series-parallel resistor film networks are respectively printed on the front side of the substrate; The back side of the substrate is printed with a whole back conductor for grounding; The single resistor film, the second resistor film and the third resistor film are respectively connected to the back conductor to achieve grounding in a manner including at least one of the following: edge grounding; through-hole grounding; bonding grounding.

[0009] In conjunction with the second aspect, in an optional implementation, The substrate comprises a cube or a cuboid; Grounding wires are printed and connected at the left edge, right edge and lower edge of the front side of the substrate; Conductors are printed on the left side, right side and lower side of the substrate to connect the grounding wire and the back conductor for grounding; A solder pad is printed at the middle of the upper edge of the front side of the substrate, which is used as the input terminal.

[0010] In conjunction with the second aspect, in an optional implementation, The substrate includes a beryllium oxide ceramic substrate.

[0011] In conjunction with the second aspect, in an optional implementation, The second resistor film and the third resistor film are printed simultaneously and one end of each is partially overlapped on the printed first resistor film, and the other end is partially overlapped on the ground line, thereby realizing a series-parallel printing structure of multiple resistor films.

[0012] In conjunction with the second aspect, in an optional implementation, The width of the first end of the single resistor film is less than or equal to the width of the second end.

[0013] In conjunction with the second aspect, in an optional implementation, The load sheet includes: a first series-parallel resistor film network and a second series-parallel resistor film network; In the first connection direction, a pad, a first resistor film of the first series-parallel resistor film network, a first conductor, a first resistor film of the second series-parallel resistor film network, a second conductor, the single resistor film and a ground line are printed in sequence and in a continuous and stacked manner.

[0014] In conjunction with the second aspect, in an optional implementation, The pad, the first resistor film of the first series-parallel resistor film network, the first conductor, the first resistor film of the second series-parallel resistor film network, the second conductor, and the first end of the single resistor film have the same width.

[0015] The beneficial effects brought by the technical solution provided in the embodiments of the present application include: 1. By printing multiple grounded resistor films at the front end of a single resistor film, a series-parallel combination printing structure of the resistor film is formed. In this way, a matching load can be achieved through a single resistor film, and signal attenuation can be achieved through multiple cross-connected resistor film branches, thereby realizing the addition of an attenuation circuit to the load sheet, and finally forming a hybrid load sheet with an attenuation circuit and a matching load. Since the load sheet can simultaneously attenuate signals and match impedance, on the one hand, the structure of the original load sheet is structurally changed, and on the other hand, the resistance deviation tolerance of the attenuation resistor film can be improved. The current printing preparation process can fully meet the requirements of the resistance deviation tolerance in one printing, so that there is no need for laser resistance adjustment, and the integrity of the entire resistor film can be guaranteed and meet the requirements of simulation design, and the influence of the reduced power bearing caused by laser resistance adjustment is abandoned, and the load sheet power bearing is guaranteed not to be affected by laser resistance adjustment, so it can adapt to the use of higher power and higher frequency at the same time, and achieve the use of more than 200W of high power while the use frequency is increased to DC~9.2GHz, breaking through the current technical barriers that can withstand high power but cannot reach high frequency, and can reach high frequency but can only withstand low power, taking into account both power and frequency.

[0016] 2. By setting at least one group of series-parallel resistor film networks and forming the first connection direction, the second connection direction and the third connection direction, multiple resistor films can be printed in a dispersed manner, avoiding the use of a large-area resistor film, and improving the uniformity of thermal image distribution under high power and high frequency. And by at least one group of series-parallel resistor film networks for signal attenuation, the area of ​​a single resistor film can be reduced, avoiding the generation of large heat under high power and high frequency, which causes the temperature in the center area to be too high and the temperature distribution to be uneven, and further improving the uniformity of thermal image distribution, so that the printed circuit can reach a higher frequency of use while being able to withstand high power.

[0017] 3. By arranging printed resistors in multiple connection directions, it is also possible to better adapt to different substrate shapes, improve the rationality of printing arrangement and achieve the best utilization of substrate area, and also reduce the size of the substrate.

[0018] Additional aspects and advantages of the embodiments of the present application will be given in part in the description below and in part will become apparent from the description below or will be learned through the practice of the embodiments of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The drawings are not necessarily drawn to scale, and local features may be enlarged or reduced to more clearly show the details of the local features. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings: Figure 1 A schematic flow chart of a specific example of a substrate printing process for a 200W high-frequency load sheet in an embodiment of the present application; Figure 2 This is a schematic diagram of the printed structure of Example 1 of a 200W high-frequency load sheet according to an embodiment of the present application; Figure 3 This is a schematic diagram of the printed structure of Example 2 of a 200W high-frequency load sheet according to an embodiment of the present application; Figure 4 for Figure 2 The left side schematic diagram of the 200W high frequency load chip; Figure 5 This is a schematic diagram of the printed structure of Example 3 of a 200W high-frequency load sheet according to an embodiment of the present application; Figure 6 This is a schematic diagram of the layout of multiple resistor films of a 200W high-frequency load sheet in an embodiment of the present application; Figure 7 This is a schematic diagram of the printed structure of Example 4 of the 200W high-frequency load sheet of an embodiment of the present application. DETAILED DESCRIPTION

[0020] In order to make the technical solutions and beneficial effects of the present application more obvious and easy to understand, the following is a detailed description by listing specific embodiments. The drawings are not necessarily drawn to scale, and local features may be enlarged or reduced to more clearly show the details of the local features; unless otherwise defined, the technical and scientific terms used herein have the same meanings as those in the technical field to which the present application belongs.

[0021] The embodiments of the present application are not exhaustive, but are only illustrative of some embodiments, and are not intended to be a specific limitation on the scope of protection of the present application. In the absence of contradiction, each step in a certain embodiment can be implemented as an independent embodiment, and the steps can be arbitrarily combined. For example, in a certain embodiment, the solution after removing some steps can also be implemented as an independent embodiment, and the order of the steps in a certain embodiment can be arbitrarily exchanged. In addition, the optional implementations in a certain embodiment can be arbitrarily combined; in addition, the embodiments can be arbitrarily combined, for example, some or all of the steps of different embodiments can be arbitrarily combined, and a certain embodiment can be arbitrarily combined with the optional implementations of other embodiments.

[0022] In each embodiment of the present application, unless otherwise specified or there is a logical conflict, the terms and / or descriptions between the embodiments are consistent and can be referenced to each other. The technical features in different embodiments can be combined to form a new embodiment based on their internal logical relationships.

[0023] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application.

[0024] In the embodiments of the present application, unless otherwise specified, elements expressed in the singular form, such as "a", "an", "the", "above", "said", "aforementioned", "this", etc., may mean "one and only one", or "one or more", "at least one", etc. For example, when using articles such as "a", "an", "the" in English in translation, the noun after the article may be understood as a singular expression or a plural expression.

[0025] In the embodiments of the present application, "plurality" refers to two or more.

[0026] In some embodiments, the terms “at least one”, “one or more”, “a plurality of”, “multiple”, etc. can be used interchangeably.

[0027] The prefixes such as "first" and "second" in the embodiments of the present application are only used to distinguish different description objects, and do not constitute restrictions on the position, order, priority, value or content of the description objects. For the statement of the description object, please refer to the description of the context in the embodiments, and no unnecessary restrictions should be constituted due to the use of prefixes. For example, the value of the description object is not limited by the ordinal number, and can be one or more. Taking "first device" as an example, the value of "device" can be one or more. In addition, the objects modified by different prefixes can be the same or different. For example, if the description object is "device", the "first device" and the "second device" can be the same device or different devices, and their types can be the same or different.

[0028] In some embodiments, the term "connection" may indicate that an electrical signal or data is transmitted between a connected end and a connected end, and may be understood as "electrical connection", "communication connection", etc. "Connection" may be a direct connection between two components, an indirect connection established through other components, internal communication between two components, or any other possible connection form.

[0029] This specification provides method operation steps such as embodiments or flow charts, but more or fewer operation steps may be included based on conventional or non-creative work. The order of steps listed in the embodiments is only one way of executing the order of many steps and does not represent the only execution order. When the actual device, system or server product is executed, it can be executed in the order of the method shown in the embodiments or the drawings or in parallel (for example, in a parallel processor or multi-threaded processing environment).

[0030] The present application embodiment provides a substrate printing process for a 200W high-frequency load sheet. Figure 1 A schematic flow chart of a specific example of a substrate printing process for a 200W high-frequency load sheet in an embodiment of the present application is shown. As shown in the figure, the substrate printing process for a 200W high-frequency load sheet includes: S1: On the front side of the substrate, a conductive paste is used to print a pad, a first conductor, a second conductor and a ground wire; after printing, the conductive paste is dried at 100°C to 150°C, and then sintered at a high temperature of 830°C to 880°C to firmly bond the conductive paste to the substrate; S2: On the reverse side of the substrate, the entire surface is printed with a conductive paste to obtain a back conductor; after printing, the conductive paste is dried at 100°C to 150°C, and then sintered at a high temperature of 830°C to 880°C to firmly bond the conductive paste to the substrate; S3: Printing conductive paste three times on the left side, right side and bottom side of the substrate, printing one of the left side, right side and bottom side each time, to obtain a conductor to connect the ground wire and the back conductor; drying at 100°C to 150°C after each printing, and then sintering at a high temperature of 830°C to 880°C to firmly bond the conductive paste to the substrate; S4: Printing the resistor paste at least three times on the front side of the substrate; performing at least one first printing and a second printing, wherein the first printing obtains a first resistor film of a series-parallel resistor film network, and the second printing simultaneously obtains a second resistor film and a third resistor film of a series-parallel resistor film network; the third printing obtains a single resistor film; drying at 100°C to 150°C after each printing, and then sintering at a high temperature of 830°C to 880°C to solidify the resistor paste and display the resistance value characteristics; Among them, the load sheet includes a single resistor film, and at least one group of series-parallel resistor film networks connected in series at the front end of the single resistor film to form a series-parallel printed structure of multiple resistor films; the first end of the single resistor film is electrically connected to the input end of the load sheet through at least one group of series-parallel resistor film networks, and the first end of the single resistor film and the input end form a first connection direction between each other; the first resistor film and the second resistor film form a second connection direction between each other; the first resistor film and the third resistor film form a third connection direction between each other; the second connection direction and the third connection direction intersect with the first connection direction respectively.

[0031] In the present application embodiment, Figure 2 As shown, through Figure 1 The substrate printing process shown can obtain a load sheet 100 including a single resistor film 11 and at least one group of series-parallel resistor film networks 12 connected in series to the front end of the single resistor film 11 to form a series-parallel printed structure of multiple resistor films.

[0032] Thus, the embodiment of the present application forms a series-parallel combination printing structure of multiple resistor films by printing multiple grounded resistor films at the front end of a single resistor film, so that a matching load can be achieved through a single resistor film, and signal attenuation can be achieved through multiple cross-connected resistor film branches, thereby realizing the addition of an attenuation circuit to the load sheet, and finally forming a hybrid load sheet with an attenuation circuit and a matching load. Since the load sheet can simultaneously attenuate signals and match impedance, on the one hand, the structure of the original load sheet is structurally changed, and on the other hand, the resistance deviation tolerance of the attenuation resistor film can be improved. The current printing preparation process can fully meet the requirements of the resistance deviation tolerance in one printing, so that there is no need for laser resistance adjustment, and the integrity of the entire resistor film can be guaranteed and meet the requirements of simulation design, and the influence of the reduced power bearing caused by laser resistance adjustment is abandoned, and the load sheet power bearing is guaranteed not to be affected by laser resistance adjustment, so it can adapt to the use of higher power and higher frequency at the same time, and achieve the use frequency of DC~9.2GHz while bearing high power of more than 200W, breaking through the current technical barriers that can withstand high power but cannot reach high frequency, and can reach high frequency but can only withstand low power, taking into account both power and frequency.

[0033] Furthermore, by setting at least one group of series-parallel resistor film networks and forming the first connection direction, the second connection direction and the third connection direction, multiple resistor films can be printed in a dispersed manner, avoiding the use of a large-area resistor film, thereby improving the uniformity of thermal image distribution under high power and high frequency. Furthermore, by performing signal attenuation through at least one group of series-parallel resistor film networks, the area of ​​a single resistor film can be reduced, avoiding the generation of large amounts of heat under high power and high frequency, thereby causing the temperature in the center area to be too high and the temperature distribution to be uneven, thereby further improving the uniformity of thermal image distribution, thereby enabling the printed circuit to achieve a higher frequency of use while being able to withstand high power.

[0034] Furthermore, by arranging printed resistors in multiple connection directions, it is also possible to better adapt to different substrate shapes, improve the rationality of printing arrangement and achieve the best utilization of substrate area, and also reduce the size of the substrate.

[0035] Exemplarily, the substrate printing process of a 200W high frequency load sheet may include the following steps: S11: Printing a conductive paste on the front side of the substrate to obtain a pad, a first conductor, a second conductor and a ground wire; drying at 100°C to 150°C after printing, and then sintering at a high temperature of 830°C to 880°C to firmly bond the conductive paste to the substrate; S12: Printing a conductive paste on the entire back side of the substrate to obtain a back conductor; drying at 100° C. to 150° C. after printing, and then sintering at a high temperature of 830° C. to 880° C. to firmly bond the conductive paste to the substrate; S13: Printing a conductive paste on the left side, right side and bottom side of the substrate three times, printing one of the left side, right side and bottom side each time, to obtain a conductor to connect the ground wire and the back conductor; drying at 100° C. to 150° C. after each printing, and then sintering at a high temperature of 830° C. to 880° C. to firmly bond the conductive paste to the substrate; S14: Print five times with resistor paste on the front side of the substrate; the first printing obtains the first resistor film of the first series parallel resistor film network; the second printing obtains the second resistor film and the third resistor film of the first series parallel resistor film network at the same time; the third printing obtains the first resistor film of the second series parallel resistor film network; the fourth printing obtains the second resistor film and the third resistor film of the second series parallel resistor film network; the fifth printing obtains a single resistor film; after each printing, dry at 100℃~150℃, and then sinter at a high temperature of 830℃~880℃ to solidify the resistor paste and show the resistance value characteristics.

[0036] In this way, the embodiment of the present application obtains the second resistor film and the third resistor film by printing simultaneously, which can ensure the consistency of the printing environment and avoid the resistance value difference caused by different printings, so that the resistance values ​​of the second resistor film and the third resistor film can be more accurately consistent, thereby improving the symmetry and thermal image uniformity.

[0037] In the embodiment of the present application, the conductive paste may be made of silver paste, or may be made of other high conductivity materials such as gold.

[0038] A first protective film can be printed on top of each group of series-parallel resistor film networks, and a second protective film can be printed on top of a single resistor film, which can improve the isolation between different resistor films. Then a third protective film is printed on top of the first and second protective films, and the third protective film can cover the first and second protective films, thereby further improving the safety and stability of the entire circuit. Then, a marking layer with the same thickness is evenly printed around the edge of the third protective film, while the traditional marking point is directly printed on one place of a layer of protective film, resulting in an uneven surface of the product and unable to be stacked flatly; the present application changes the traditional marking method to form an edge mark, thereby improving the surface flatness of the product, allowing the product to be stacked, facilitating subsequent processing, while also improving the marking ability and recognizability, so that the products can not only have the same spacing, but also maintain the consistency of the upper and lower alignment. For example, each layer of protective film can be a black protective film.

[0039] The resistor pastes used for the single resistor film, the first resistor film, the second resistor film and the third resistor film can be selected to be the same or different according to actual needs. For example, the single resistor film can use 65wt.% silver powder with an average diameter of 420nm, 6wt.% organic cellulose binder (mixture of nitrocellulose and rosin), 5wt.% glass powder with an average diameter of 250nm, 0.4wt.% fumed silica and the balance pine alcohol, wherein the glass powder includes 45wt.% silicon oxide and 55wt.% aluminum oxide, so as to improve the accuracy of the obtained resistance value and improve the impedance matching. The first resistor film, the second resistor film and the third resistor film can be made of 50wt.% silver powder with an average diameter of 550nm, 12wt.% organic cellulose binder (mixture of nitrocellulose and rosin), 8wt.% glass powder with an average diameter of 300nm, 0.6wt.% fumed silica and the balance pinene alcohol, wherein the glass powder includes 40wt.% silicon oxide and 60wt.% aluminum oxide to improve the stability of the obtained resistance value under high power and high frequency. All of them can be prepared by the technical solutions well known to those skilled in the art, which will not be repeated in this specific embodiment.

[0040] Thus, the embodiment of the present application provides a high-power, high-frequency load sheet that can be printed on a substrate and can be applied to many fields such as modern communications, radar, and electronic countermeasures. It can meet the needs of high-frequency use within the passband of DC to 9.2 GHz and power of more than 200 W.

[0041] The embodiment of the present application provides a 200W high frequency load sheet, Figure 2 The schematic diagram of the printed structure of Example 1 of the 200W high-frequency load sheet of the embodiment of the present application is shown. As shown in the figure, the load sheet 100 includes: a single resistor film 11; and at least one group of series-parallel resistor film networks 12 connected in series to the front end of the single resistor film 11 to form a series-parallel printed structure of multiple resistor films; The first end 111 of the single resistor film 11 is electrically connected to the input terminal IN through at least one set of series-parallel resistor film networks, and the second end 112 of the single resistor film 11 is grounded to achieve load matching; the first end 111 of the single resistor film 11 and the input terminal IN form a first connection direction S1 between each other; The series-parallel resistor film network 12 is printed to include a first resistor film 121, a second resistor film 122 and a third resistor film 123 that are electrically connected; the first resistor film 121 is printed on the first connection direction S1 and is electrically connected between the input terminal IN and the first end 111 of the single resistor film 11, the second resistor film 122 and the third resistor film 123 are respectively printed on both sides of the first resistor film 121 and are grounded respectively; the first resistor film 121 and the second resistor film 122 form a second connection direction S2 between each other; the first resistor film 121 and the third resistor film 123 form a third connection direction S3 between each other; the second connection direction S2 and the third connection direction S3 respectively intersect with the first connection direction S1; the series-parallel resistor film network 12 is used to attenuate the input signal received by the input terminal IN.

[0042] Thus, the embodiment of the present application forms a series-parallel combination printing structure of multiple resistor films by printing multiple grounded resistor films at the front end of a single resistor film, so that a matching load can be achieved through a single resistor film, and signal attenuation can be achieved through multiple cross-connected resistor film branches, thereby realizing the addition of an attenuation circuit to the load sheet, and finally forming a hybrid load sheet with an attenuation circuit and a matching load. Since the load sheet can simultaneously attenuate signals and match impedance, on the one hand, the structure of the original load sheet is structurally changed, and on the other hand, the resistance deviation tolerance of the attenuation resistor film can be improved. The current printing preparation process can fully meet the requirements of the resistance deviation tolerance in one printing, so that there is no need for laser resistance adjustment, and the integrity of the entire resistor film can be guaranteed and meet the requirements of simulation design, and the influence of the reduced power bearing caused by laser resistance adjustment is abandoned, and the load sheet power bearing is guaranteed not to be affected by laser resistance adjustment, so it can adapt to the use of higher power and higher frequency at the same time, and achieve the use frequency of DC~9.2GHz while bearing high power of more than 200W, breaking through the current technical barriers that can withstand high power but cannot reach high frequency, and can reach high frequency but can only withstand low power, taking into account both power and frequency.

[0043] Furthermore, by setting at least one group of series-parallel resistor film networks and forming the first connection direction, the second connection direction and the third connection direction, multiple resistor films can be printed in a dispersed manner, avoiding the use of a large-area resistor film, thereby improving the uniformity of thermal image distribution under high power and high frequency. Furthermore, by performing signal attenuation through at least one group of series-parallel resistor film networks, the area of ​​a single resistor film can be reduced, avoiding the generation of large amounts of heat under high power and high frequency, thereby causing the temperature in the center area to be too high and the temperature distribution to be uneven, thereby further improving the uniformity of thermal image distribution, thereby enabling the printed circuit to achieve a higher frequency of use while being able to withstand high power.

[0044] Furthermore, by arranging printed resistors in multiple connection directions, it is also possible to better adapt to different substrate shapes, improve the rationality of printing arrangement and achieve the best utilization of substrate area, and also reduce the size of the substrate.

[0045] In some possible implementations, such as Figure 2 As shown, the second resistor film 122, the first resistor film 121 and the third resistor film 123 can be arranged in sequence from right to left to form a continuous resistor film strip. Then, the second connection direction S2 and the third connection direction S3 can overlap, that is, they are in the same direction, and can be perpendicular to the first connection direction S1. Then, a series-parallel printing structure can be formed, in which the second resistor film 122, the first resistor film 121 and the third resistor film 123 are separated by avoiding the use of conductors. Compared with the two resistor films connected by conductors in the symmetrical attenuation channel of the current π-type attenuation circuit for the convenience of laser resistance adjustment, the first resistor film 121 can increase the resistance of conducting power from the input end of the load sheet to the ground through the second resistor film 122 and the third resistor film 123, thereby improving the power consumption efficiency and increasing the power and use frequency that the load sheet can withstand.

[0046] In some possible implementations, Figure 3 FIG. 2 shows a schematic diagram of the printed structure of Example 2 of a 200W high frequency load sheet according to an embodiment of the present application. Figure 3 As shown, in any one or more groups of at least one group of series-parallel resistor film networks 22 included in the load sheet 200, the second resistor film 222 can be divided into a plurality of sub-resistance films 2221, 2222 with equal or unequal areas; the third resistor film 223 can be divided into a plurality of sub-resistance films 2231, 2232 with equal or unequal areas. Then, another series-parallel printing structure can be formed, which reduces the maximum area of ​​the second and third resistor films, and can further improve the uniformity of thermal image distribution and the performance and stability of the entire circuit.

[0047] In an optional implementation, the lengths of the connecting parts of the first resistor film 121, the second resistor film 122 and the third resistor film 123 along the first connection direction S1 are equal; And / or, the second connection direction S2 and the third connection direction S3 are parallel or overlapped, and the second resistance film 122 and the third resistance film 123 have the same area.

[0048] In some possible implementations, such as Figure 2 As shown, the first resistor film 121 , the second resistor film 122 and the third resistor film 123 may have the same width (the length dimension along the first connection direction S1 ) to make the edges continuous, thereby improving circuit performance and stability, such as being able to reduce undesired signal reflections.

[0049] The second resistor film 122 and the third resistor film 123 may have the same length (the length along the second connection direction S2 or the third connection direction S3), so that the second resistor film 122 and the third resistor film 123 have the same area. In this way, the load sheet can have a symmetrical printing structure, further improving the uniformity of the thermal image distribution and the performance and stability of the entire circuit.

[0050] Figure 4 Shows Figure 2 A left side schematic diagram of a 200W high frequency load sheet. As shown in the figure, in an optional embodiment, the load sheet 100 further includes: a substrate 14; The single resistor film 11 and at least one group of series-parallel resistor film networks 12 are respectively printed on the front surface of the substrate 14; The back side of the substrate 14 is printed with a whole back conductor 15 for grounding; The single resistor film 11 , the second resistor film 122 and the third resistor film 123 are respectively connected to the back conductor 14 to achieve grounding in a manner including at least one of the following: edge grounding; through-hole grounding; bonding grounding.

[0051] In this way, the embodiment of the present application prints the entire back conductor on the back of the substrate, which can be grounded after being welded, thereby improving the performance and stability of the entire circuit.

[0052] In an optional embodiment, the substrate 14 includes a cube or a cuboid; Grounding wires 13 are printed and connected at the left edge, right edge and bottom edge of the front side of the substrate 14; Conductors 16 are printed on the left side, right side and bottom side of the substrate 14 to connect the grounding wire 13 and the back conductor 15 for grounding; A pad 17 is printed at the middle of the upper edge of the front side of the substrate 14 and is used as the input terminal IN.

[0053] In the embodiment of the present application, the substrate 14 may also include a circle or an ellipse with a curved boundary, or an irregular shape with a curved boundary and a straight boundary, or the substrate may also be a polygon, etc., which can be set according to actual needs.

[0054] Figure 5 The printed structure diagram of Example 3 of the 200W high-frequency load sheet of the embodiment of the present application is shown. As shown in the figure, in some possible implementations, the load sheet 300 includes a circular substrate 34, thereby expanding the scope of application.

[0055] Then, the load sheet 300 includes: a single resistor film 31; and at least one group of series-parallel resistor film networks 32 connected in series to the front end of the single resistor film 31 to form a series-parallel printed structure of multiple resistor films; The first end 311 of the single resistor film 31 is electrically connected to the input terminal IN through at least one set of series-parallel resistor film networks, and the second end 312 of the single resistor film 31 is grounded to achieve load matching; the first end 311 of the single resistor film 31 and the input terminal IN form a first connection direction S1 between each other; The series-parallel resistor film network 32 is printed to include a first resistor film 321, a second resistor film 322 and a third resistor film 323; the first resistor film 321 is printed on the first connection direction S1 and is electrically connected between the input terminal IN and the first end 111 of the single resistor film 31, the second resistor film 322 and the third resistor film 323 are respectively printed on both sides of the first resistor film 321 and are respectively grounded; the first resistor film 321 and the second resistor film 322 form a second connection direction S2 between each other; the first resistor film 321 and the third resistor film 323 form a third connection direction S3 between each other; the second connection direction S2 and the third connection direction S3 respectively intersect with the first connection direction S1; the series-parallel resistor film network 32 is used to attenuate the input signal received by the input terminal IN.

[0056] Other features of the load sheet 300 of the embodiment of the present application may be the same as those of the load sheets 100 and 200, or the technical features of the above embodiments may be arbitrarily combined to form another embodiment of the present application that may not be explicitly described. For details, please refer to the above and the following, which will not be repeated here.

[0057] Among them, by arranging the first resistor film 321, the second resistor film 322 and the third resistor film 323 to have an arc-shaped boundary, the paths through the second resistor film 322 and the third resistor film 323 to the ground can be equal or approximately equal, thereby improving power consumption efficiency and increasing the power and usage frequency that the load sheet can withstand.

[0058] Furthermore, the arc-shaped connection surface between the second end 312 of the single resistor film 31 and the ground line 33 extends the length of the second end 312, so that the connection length is longer than that of a planar connection surface, thereby improving the impedance matching performance of the load sheet.

[0059] In an optional embodiment, the substrate comprises a beryllium oxide ceramic substrate. Thus, through the excellent heat dissipation capability of ceramics, it is possible to avoid excessive local temperature of the device when receiving power, thereby preventing the circuit from being burned.

[0060] In some possible implementations, the substrate may also be made of ceramic materials such as Al2O3, AlN, or high thermal conductivity materials such as SiC, diamond, etc.

[0061] In an optional embodiment, the second resistor film 122 and the third resistor film 123 are printed simultaneously and one end of both are printed partially overlapping on the printed first resistor film 121, and the other end is printed partially overlapping on the ground line 13, thereby realizing a series-parallel printing structure of multiple resistor films.

[0062] For example, Figure 6 The schematic diagram of the layout of multiple resistor films of a 200W high-frequency load sheet in an embodiment of the present application is shown. As shown in the figure, multiple series-parallel combinations are used, wherein in the first series-parallel resistor film network, the first resistor film 121 can be R1, and R1 is an independent resistance value. The second resistor film 122 is R2, and the third resistor film 123 is R3, and the resistance values ​​of R2 and R3 are equal. R2 and R3 are connected in parallel, and then connected in series and parallel with R1 to form a group of attenuation circuits. Similarly, in the second series-parallel resistor film network, the first resistor film can be R4, and R4 is an independent resistance value. The second resistor film is R5, and the third resistor film is R6, and the resistance values ​​of R5 and R6 are equal. R5 and R6 are connected in parallel, and then connected in series and parallel with R4 to form a group of attenuation circuits. The single resistor film 11 can be R7, which serves as the final matching load, so that the entire circuit is realized as a hybrid circuit with an attenuation circuit and a matching load. The input signal enters the load sheet 100 from the input terminal IN, and part of the signal is conducted to the ground through the pad 17, the first resistor film 121 of the first series-parallel resistor film network, the first conductor, the first resistor film of the second series-parallel resistor film network, the second conductor and the single resistor film 11; another part of the signal is conducted to the ground through the second resistor film 122 and the third resistor film 123 of the first series-parallel resistor film network; and another part of the signal is conducted to the ground through the second resistor film and the third resistor film of the second series-parallel resistor film network.

[0063] In an optional implementation, the width of the first end 111 of the single resistor film 11 is less than or equal to the width of the second end 112 .

[0064] In this way, if the width of the first end 111 of the single resistor film 11 is smaller than the width of the second end 112 , the single resistor film 11 is a trapezoidal printed structure, which can achieve better impedance matching and increase the operating frequency.

[0065] In an alternative embodiment, if Figure 2 As shown, the load sheet 100 includes: a first series-parallel resistor film network and a second series-parallel resistor film network; In the first connection direction S1, a pad 17, a first resistor film 121 of the first series-parallel resistor film network, a first conductor, a first resistor film of the second series-parallel resistor film network, a second conductor, the single resistor film 11 and a ground line 13 are printed in sequence in a continuous and stacked manner.

[0066] Thus, through continuous stacking or overlapping printing, the reliability of signal transmission can be improved, and the performance and stability of the entire circuit can be improved. It is also more conducive to ensuring width consistency, avoiding unnecessary signal reflections caused by intermittent connections using conductors of different widths, and thus avoiding affecting the circuit's power tolerance and characteristics.

[0067] In an optional embodiment, the pad 17, the first resistor film 121 of the first series-parallel resistor film network, the first conductor, the first resistor film of the second series-parallel resistor film network, the second conductor and the first end 111 of the single resistor film 11 are equal in width.

[0068] In this way, by making the width equal, a continuous boundary can be ensured, signal reflection can be reduced, and the performance and stability of the entire circuit can be improved.

[0069] Figure 7 The printed structure diagram of Example 4 of the 200W high-frequency load sheet of the embodiment of the present application is shown. As shown in the figure, in some possible implementations, the load sheet 400 can divide a single resistor film into multiple matching resistor films 411 and 412. In this way, through multiple matching resistor films, it can have multi-segment matching characteristics, further improve thermal image uniformity, and reduce load costs.

[0070] Other features of the load sheet 400 of the embodiment of the present application may be the same as those of the load sheets 100, 200, and 300, or the technical features of the above embodiments may be arbitrarily combined to form another embodiment of the present application that may not be explicitly described. For details, please refer to the above and will not be repeated here.

[0071] The load sheets of Example 1, Example 2, Example 3 or Example 4 of the embodiments of the present application can be printed by using the substrate printing process of the above-mentioned load sheet.

[0072] It should be understood that the above embodiments are exemplary and are not intended to include all possible implementations. Various modifications and changes may also be made on the basis of the above embodiments without departing from the scope of the present disclosure. Similarly, the various technical features of the above embodiments may also be combined arbitrarily to form other embodiments of the present application that may not be clearly described. Therefore, the above embodiments only express several implementations of the present application and do not limit the scope of protection of the patent of this application.

Claims

1. A substrate printing process for a 200W high-frequency load sheet, characterized in that: include: On the front side of the substrate, a conductive paste is used for printing to obtain a pad, a first conductor, a second conductor and a ground line; After printing, it is dried at 100℃~150℃, and then sintered at 830℃~880℃ to make the conductive paste firmly bonded to the substrate; On the reverse side of the substrate, the entire surface is printed with conductive paste to obtain a back conductor; After printing, it is dried at 100℃~150℃, and then sintered at 830℃~880℃ to make the conductive paste firmly bonded to the substrate; Conductive paste is printed three times on the left side, right side and bottom side of the substrate, and one of the left side, right side and bottom side is printed each time to obtain a conductor to connect the ground wire and the back conductor; after each printing, it is dried at 100°C to 150°C, and then sintered at a high temperature of 830°C to 880°C to firmly bond the conductive paste to the substrate; Printing a resistor paste at least three times on the front side of the substrate; At least one first printing and a second printing are performed, wherein the first printing obtains a first resistor film of a series-parallel resistor film network, and the second printing simultaneously obtains a second resistor film and a third resistor film of a series-parallel resistor film network; The third printing obtains a single resistor film; after each printing, it is dried at 100°C to 150°C, and then sintered at a high temperature of 830°C to 880°C to solidify the resistor paste and show the resistance value characteristics; Wherein, the load sheet includes a single resistor film and at least one group of series-parallel resistor film networks connected in series to the front end of the single resistor film to form a series-parallel printed structure of multiple resistor films; The first end of the single resistor film is electrically connected to the input end of the load sheet through at least one group of series-parallel resistor film networks, and the first end of the single resistor film and the input end form a first connection direction with each other; the first resistor film and the second resistor film form a second connection direction with each other; the first resistor film and the third resistor film form a third connection direction with each other; the second connection direction and the third connection direction intersect with the first connection direction respectively.

2. A 200W high frequency load sheet, characterized in that: The load sheet includes: a single resistor film; and at least one group of series-parallel resistor film networks connected in series to the front end of the single resistor film to form a series-parallel printed structure of multiple resistor films; The first end of the single resistor film is electrically connected to the input end through at least one set of series-parallel resistor film networks, and the second end of the single resistor film is grounded to achieve load matching; the first end of the single resistor film and the input end form a first connection direction with each other; The printed series-parallel resistor film network includes a first resistor film, a second resistor film and a third resistor film that are electrically connected; the first resistor film is printed in the first connection direction and is electrically connected between the input end and the first end of the single resistor film, the second resistor film and the third resistor film are respectively printed on both sides of the first resistor film and are grounded respectively; the first resistor film and the second resistor film form a second connection direction between each other; the first resistor film and the third resistor film form a third connection direction between each other; the second connection direction and the third connection direction intersect with the first connection direction respectively; the series-parallel resistor film network is used to attenuate the input signal received by the input end.

3. The 200W high frequency load sheet according to claim 2, characterized in that: The lengths of the connection points of the first resistance film, the second resistance film and the third resistance film along the first connection line direction are equal; And / or, the second connection direction and the third connection direction are parallel or overlapped, and the second resistance film and the third resistance film have the same area.

4. The 200W high frequency load sheet according to claim 2, characterized in that: The load sheet further comprises: a substrate; The single resistor film and at least one group of series-parallel resistor film networks are respectively printed on the front side of the substrate; The back side of the substrate is printed with a whole back conductor for grounding; The single resistor film, the second resistor film and the third resistor film are respectively connected to the back conductor to achieve grounding in a manner including at least one of the following: edge grounding; through-hole grounding; bonding grounding.

5. The 200W high frequency load sheet according to claim 4, characterized in that: The substrate comprises a cube or a cuboid; Grounding wires are printed and connected at the left edge, right edge and lower edge of the front side of the substrate; Conductors are printed on the left side, right side and lower side of the substrate to connect the grounding wire and the back conductor for grounding; A solder pad is printed at the middle of the upper edge of the front side of the substrate, which is used as the input terminal.

6. The 200W high frequency load sheet according to claim 4, characterized in that: The substrate includes a beryllium oxide ceramic substrate.

7. The 200W high frequency load sheet according to claim 2, characterized in that: The second resistor film and the third resistor film are printed simultaneously and one end of each is partially overlapped on the printed first resistor film, and the other end is partially overlapped on the ground line, thereby realizing a series-parallel printing structure of multiple resistor films.

8. The 200W high frequency load sheet according to claim 2, characterized in that: The width of the first end of the single resistor film is less than or equal to the width of the second end.

9. The 200W high frequency load sheet according to any one of claims 2 to 8, characterized in that: The load sheet includes: a first series-parallel resistor film network and a second series-parallel resistor film network; In the first connection direction, a pad, a first resistor film of the first series-parallel resistor film network, a first conductor, a first resistor film of the second series-parallel resistor film network, a second conductor, the single resistor film and a ground line are printed in sequence and in a continuous and stacked manner.

10. The 200W high frequency load sheet according to claim 9, characterized in that: The pad, the first resistor film of the first series-parallel resistor film network, the first conductor, the first resistor film of the second series-parallel resistor film network, the second conductor, and the first end of the single resistor film have the same width.

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