A built-in cavity type radiating antenna unit and preparation method thereof

Abstract

The present invention relates to a built-in cavity type radiating antenna unit and a preparation method thereof, wherein the built-in cavity type radiating antenna unit comprises an antenna unit body formed by laminating and sintering multiple layers of ceramic sheets, wherein the antenna unit body comprises a top radiating unit structure layer, an intermediate cavity layer and a base feed network structure layer; the intermediate cavity layer is provided with a plurality of built-in cavities that are connected from top to bottom, the top radiating unit structure layer is provided with a plurality of exhaust ports, and each built-in cavity is connected to a corresponding exhaust port through an exhaust channel; a plurality of interconnected metallized holes are provided in the intermediate cavity layer and the base feed network structure layer, and the plurality of interconnected metallized holes are interconnected through conductor printed patterns preset in the antenna unit body; a portion of the top radiating unit structure layer located in the built-in cavity is provided with a radiating patch conductor pattern. The present invention can also replace a larger plane with a small space to meet the requirements of high-density integration and high assembly consistency in the current TR component production.

Description

Technical Field

[0001] The present invention relates to the technical field of radiating antennas, and in particular to a built-in cavity type radiating antenna unit and a preparation method thereof. Background Art

[0002] Low temperature co-fired ceramics (LTCC) have become the preferred technology for composite, integrated and modular electronic components due to their diverse designs, excellent high-frequency performance, and comprehensive physical, chemical and mechanical properties such as co-firing with high-conductivity metals, as well as process performance suitable for mass production. They are the key technology for designing and manufacturing RF microwave integrated components, modules and realizing high-density integrated subsystems or systems. In recent years, the rapid development of three-dimensional assembly technology in the production of TR components in phased array radars has put forward higher requirements for the integration and assembly consistency of LTCC devices. Summary of the invention

[0003] In order to avoid the deficiencies of the prior art radiating antenna unit, the present invention provides a built-in cavity type radiating antenna unit and a preparation method thereof.

[0004] The technical solution of the present invention to solve the above technical problems is as follows: a built-in cavity type radiating antenna unit, including an antenna unit body formed by laminating and sintering multiple layers of ceramic sheets, the antenna unit body including a top radiating unit structure layer, an intermediate cavity layer and a base feeding network structure layer; the intermediate cavity layer is provided with a plurality of built-in cavities penetrating from top to bottom, the top radiating unit structure layer is provided with a plurality of exhaust ports, each of the built-in cavities is connected to the corresponding exhaust port through an exhaust channel; a plurality of interconnected metallized holes are provided in the intermediate cavity layer and the base feeding network structure layer, and the plurality of interconnected metallized holes are interconnected by internal conductor printed patterns arranged in the intermediate cavity layer and the base feeding network structure layer; the portion of the top radiating unit structure layer located in the built-in cavity is provided with a radiating patch conductor pattern.

[0005] The beneficial effects of the present invention are as follows: the present invention has a built-in cavity-type radiating antenna unit, which can realize the signal transmission requirements in a certain frequency band. The present invention can also replace a larger plane with a small space to meet the requirements of high-density integration and high assembly consistency in the current TR component production.

[0006] Based on the above technical solution, the present invention can also be improved as follows.

[0007] Furthermore, the top radiation unit structure layer comprises two layers of ceramic sheets, the middle cavity layer comprises eight layers of ceramic sheets, and the base feed network structure layer comprises ten layers of ceramic sheets.

[0008] Furthermore, a plurality of external cavities are opened on the top of the antenna unit body, and the opening depth of the external cavities is the same as the built-in depth of the built-in cavity.

[0009] Furthermore, an outer cavity is provided in the middle and around the edges of the antenna unit body.

[0010] A method for preparing a built-in cavity type radiating antenna unit comprises the following steps:

[0011] Processing electrical connection holes on the green porcelain tape forming the middle cavity layer and the base feed network structure layer, filling the electrical connection holes on the green porcelain tape with gold paste, forming interconnection metallized holes after drying, and then printing conductor printed patterns on part of the green porcelain tape and drying;

[0012] Processing exhaust holes and radiation patch conductor patterns on the raw porcelain tape forming the top radiation unit structure layer, processing exhaust channel holes on part of the raw porcelain tape forming the middle cavity layer, processing built-in cavity holes on the raw porcelain tape forming the middle cavity layer, processing outer cavity holes on the raw porcelain tape forming the middle cavity layer and the base feed network structure layer;

[0013] laminating the raw ceramic tapes forming the base feed network structure layer to form a base blank;

[0014] Prepare sacrificial materials and inlay molds; laminate raw porcelain tapes with built-in cavity holes and interconnected metallized holes on the base blank layer by layer, fill sacrificial materials in each layer of built-in cavity holes layer by layer, and then laminate raw porcelain tapes with exhaust channel holes layer by layer; then place the inlay mold into the outer cavity formed by the outer cavity holes to form the antenna unit blank;

[0015] The antenna unit blank is sealed and isostatically laminated, and the laminated antenna unit blank is co-sintered to obtain a built-in cavity type radiation antenna unit.

[0016] The beneficial effect of the present invention is that the preparation method of the built-in cavity type radiating antenna unit of the present invention, by selecting sacrificial materials as the preparation process and lamination method of the inlay, can achieve good consistency in the flatness of the prepared antenna unit, thereby ensuring the assembly efficiency and assembly quality of the antenna unit in subsequent assembly.

[0017] Furthermore, the sacrificial material is first prepared into a filling blank and then filled into the built-in cavity hole layer by layer.

[0018] The beneficial effect of adopting the above further solution is: the filling effect is better.

[0019] Furthermore, the sacrificial material is propylene carbonate, and the propylene carbonate is prepared into a filling blank by hot pressing, the temperature of the hot pressing is 60-90° C., and the pressure of the hot pressing is 12-20 MPa.

[0020] Furthermore, the exhaust holes, exhaust channel holes, built-in cavity holes and outer cavity holes are laser processed by ultraviolet laser, the power of laser processing is 4.2-5W, the pulse frequency of laser processing is 60-80KHz, and the laser cutting speed of laser processing is 800mm / s.

[0021] Furthermore, the green ceramic tape forming the base feed network structure layer is laminated at a lamination temperature of 50 to 80° C., a pressure of 2000 to 2500 psi, and a pressure holding time of 8 to 15 minutes.

[0022] Furthermore, the single piece thickness of all raw ceramic sheets is 114um and the size is 8 inches. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the top view of the structure of the built-in cavity type radiating antenna unit of the present invention;

[0024] Figure 2 for Figure 1 Schematic diagram of the cross-sectional structure of AA;

[0025] Figure 3 for Figure 1 Schematic diagram of the cross-sectional structure of the middle BB;

[0026] Figure 4 The process flow of the method for preparing the built-in cavity type radiating antenna unit of the present invention is as follows Figure 1 ;

[0027] Figure 5 The process flow of the method for preparing the built-in cavity type radiating antenna unit of the present invention is as follows Figure 2 .

[0028] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0029] 1. Top radiation unit structure layer; 2. Middle cavity layer; 3. Base feed network structure layer; 4. Built-in cavity; 5. Exhaust channel; 6. Exhaust port; 7. Interconnection metallized hole; 8. Conductor printing pattern; 9. External cavity; 10. Radiating patch conductor pattern. DETAILED DESCRIPTION

[0030] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0031] like Figure 1 to Figure 3As shown, a built-in cavity type radiating antenna unit of the present embodiment includes an antenna unit body formed by laminating and sintering multiple layers of ceramic sheets, the antenna unit body includes a top radiating unit structure layer 1, an intermediate cavity layer 2 and a base feed network structure layer 3; the intermediate cavity layer 2 is provided with a plurality of built-in cavities 4 which pass through from top to bottom, the top radiating unit structure layer 1 is provided with a plurality of exhaust ports 6, each of the built-in cavities 4 is connected to the corresponding exhaust port 6 through an exhaust channel 5; a plurality of interconnected metallized holes 7 are provided in the intermediate cavity layer 2 and the base feed network structure layer 3, and the plurality of interconnected metallized holes 7 are interconnected by internal conductor printed patterns arranged in the intermediate cavity layer 2 and the base feed network structure layer 3; the portion of the top radiating unit structure layer 1 located in the built-in cavity 4 is provided with a radiating patch conductor pattern 10.

[0032] A further solution of this embodiment is as follows: Figure 2 As shown, the top radiation unit structure layer 1 includes two layers of ceramic sheets, the middle cavity layer 2 includes eight layers of ceramic sheets, and the base feed network structure layer 3 includes ten layers of ceramic sheets.

[0033] A further solution of this embodiment is as follows: Figure 2 As shown, a plurality of outer cavities 9 are opened on the top of the antenna unit body, and the opening depth of the outer cavities 9 is the same as the built-in depth of the built-in cavity 4.

[0034] like Figure 1 and Figure 3 As shown, in this embodiment, the middle position and the four edges of the antenna unit body are provided with an outer cavity 9.

[0035] The built-in cavity radiating antenna unit of this embodiment can realize the signal transmission requirements in a specific frequency band. The built-in cavity radiating antenna unit of this embodiment can also replace a larger plane with a small space to meet the requirements of high-density integration and high assembly consistency in the current TR component production.

[0036] The method for preparing the above-mentioned internal cavity type radiating antenna unit of this embodiment comprises the following steps:

[0037] Electrical connection holes are processed on the green porcelain tape forming the intermediate cavity layer 2 and the base feed network structure layer 3, and the electrical connection holes on the green porcelain tape are filled with gold paste, and after drying, interconnection metallization holes 7 are formed, and then conductor printing patterns 8 and radiation patch conductor patterns 10 are printed on part of the green porcelain tape and dried;

[0038] Process exhaust holes on the raw porcelain tape forming the top radiation unit structure layer 1, process exhaust channel holes on part of the raw porcelain tape forming the middle cavity layer 2, process built-in cavity holes on the raw porcelain tape forming the middle cavity layer 2, and process outer cavity holes on the raw porcelain tape forming the middle cavity layer 2 and the base feed network structure layer 3;

[0039] Laminating the raw ceramic tapes forming the base feed network structure layer 3 to form a base blank;

[0040] Prepare sacrificial materials and inlay molds; laminate raw porcelain tapes with built-in cavity holes and interconnected metallized holes 7 on the base blank layer by layer, fill each layer of built-in cavity holes with sacrificial materials layer by layer, and then laminate raw porcelain tapes with exhaust channel holes layer by layer; then put the inlay mold into the outer cavity 9 formed by the outer cavity holes to form the antenna unit blank; wherein the inlay mold can be prepared by using silicone rubber.

[0041] The antenna unit blank is sealed and isostatically laminated, and the laminated antenna unit blank is co-sintered to obtain a built-in cavity type radiation antenna unit.

[0042] Specifically, the sacrificial material is first prepared into a filling blank and then filled into the built-in cavity hole layer by layer, so that the filling effect is better. The sacrificial material is propylene carbonate, and the propylene carbonate is prepared into a filling blank by hot pressing, and the temperature of the hot pressing is 60-90°C and the pressure of the hot pressing is 12-20MPa.

[0043] The exhaust holes, exhaust channel holes, built-in cavity holes and outer cavity holes are laser processed by ultraviolet laser, the power of laser processing is 4.2-5W, the pulse frequency of laser processing is 60-80KHz, and the laser cutting speed of laser processing is 800mm / s.

[0044] Specifically, the lamination temperature of the green ceramic tape forming the base feed network structure layer 3 is 50-80° C., the pressure is 2000-2500 psi, and the pressure holding time is 8-15 minutes. The single piece thickness of all green ceramic sheets in this embodiment is 114 um and the size is 8 inches.

[0045] The method for preparing the above-mentioned built-in cavity type radiating antenna unit of this embodiment is as follows: Figure 4 and Figure 5 As shown, the specific steps include:

[0046] S1, through-hole processing: providing the first to twentieth green ceramic sheets, and processing electrical connection holes, subsequent process alignment holes and stacking alignment holes on each layer of green ceramic sheets by using a mechanical punching machine, wherein each green ceramic sheet has a thickness of 114um and a size of 8 inches;

[0047] S2, metal filling and conductor printing: gold paste is filled on each raw ceramic sheet to form interconnected metallized holes 7, and then conductor patterns 8 and radiation patch conductor patterns 10 are printed on some raw ceramic sheets, wherein a primary drying is performed after the holes are filled, and a secondary drying is performed after the conductors are printed. The drying temperature of the primary drying and the secondary drying is 70°C, and the drying time is 15 minutes;

[0048] S3, laser punching: using ultraviolet laser to process the first raw ceramic sheet and the second raw ceramic sheet to form the cavity hole and the exhaust port 6, the laser processing parameters are power 4.2-5W, pulse frequency 60-80KHz, laser cutting speed 800mm / s;

[0049] Ultraviolet laser is used to process the exhaust channel holes, the outer cavity holes and the built-in cavity holes of the third and fourth raw ceramic sheets. The laser processing parameters are power 4.2-5W, pulse frequency 60-80KHz, and laser cutting speed 800mm / s.

[0050] Ultraviolet laser is used to process the built-in cavity holes and the outer cavity holes of the fifth to tenth raw ceramic slices. The laser processing parameters are power 4.2-5W, pulse frequency 60-80KHz, and laser cutting speed 800mm / s.

[0051] S4, bottom structure lamination: using an aluminum laminate, laminating the eleventh raw ceramic sheet to the twentieth raw ceramic sheet, and then laminating to obtain a base blank; the laminating parameters are 70°C, pressure 2500psi, and pressure holding for 10 minutes, wherein the alignment between different raw ceramics is achieved by the positioning pins on the laminate and the lamination alignment holes on the raw ceramic sheets;

[0052] S5, preparing an organic sacrificial material for internal filling: the organic sacrificial material is propylene carbonate, and the sacrificial material-filled blank is prepared by combining hot pressing molding and stamping separation, with a hot pressing temperature of 80° C. and a pressure of 15 MPa;

[0053] Using organic glass tooling, prepare an inlay mold for the outer shape cavity during the lamination process, as a supporting material for the outer shape cavity 9 during the lamination process;

[0054] S6, sacrificial material filling: take the third to tenth green ceramic sheets, stack them layer by layer on the base blank laminated in S4, and fill the built-in cavity 5 with sacrificial materials in sequence;

[0055] S7, laminating the top layer: then laminating the first raw ceramic sheet and the second raw ceramic sheet on the uppermost layer, padding the outer cavity 9 with the processed Malan film, placing the inlay mold, and then sealing it with a vacuum sealing machine to obtain a sealed blank;

[0056] S8, lamination after mold filling: isostatically laminating the sealed blank completed in S7, with a lamination pressure of 17.5 MPa and a lamination temperature of 70°C, preheating for 5 minutes, holding the pressure for 10 minutes, and taking out the inlay mold after lamination;

[0057] S9, sintering: co-sinter the laminated green body in S8, add the gasification stage of organic matter in the sintering curve, exhaust temperature 500°C, and keep warm for 2 hours. Slice the whole green body after sintering with a grinding wheel to slice it into separate radiating antenna units, and remove the process border to obtain the built-in cavity type radiating antenna unit of this embodiment.

[0058] The preparation method of the built-in cavity-type radiating antenna unit of the present embodiment, by selecting sacrificial materials as the preparation process and lamination method of the inlay, can achieve good consistency in the flatness of the prepared antenna unit, thereby ensuring the assembly efficiency and quality of the antenna unit in subsequent assembly.

[0059] In the description of the present invention, it is necessary to understand that the orientations or positional relationships indicated by the terms "upper", "lower", "top", "bottom", "inside", "outside", etc. are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0060] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0061] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it 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, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0062] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0063] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0064] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A built-in cavity type radiating antenna unit, characterized in that: The antenna unit body is formed by laminating and sintering multiple layers of ceramic sheets, and the antenna unit body includes a top radiation unit structure layer, an intermediate cavity layer and a base feed network structure layer; the intermediate cavity layer is provided with a plurality of built-in cavities that penetrate from top to bottom, and the top radiation unit structure layer is provided with a plurality of exhaust ports, and each of the built-in cavities is connected to the corresponding exhaust port through an exhaust channel; a plurality of interconnected metallized holes are provided in the intermediate cavity layer and the base feed network structure layer, and the plurality of interconnected metallized holes are interconnected through internal conductor printed patterns arranged in the intermediate cavity layer and the base feed network structure layer; a portion of the top radiation unit structure layer located in the built-in cavity is provided with a radiation patch conductor pattern; The top radiation unit structure layer comprises two layers of ceramic sheets, the middle cavity layer comprises eight layers of ceramic sheets, and the base feed network structure layer comprises ten layers of ceramic sheets; A plurality of external cavities are provided on the top of the antenna unit body, and the depth of the external cavities is the same as the built-in depth of the built-in cavity; The middle position and surrounding edges of the antenna unit body are provided with an outer cavity.

2. A method for preparing the built-in cavity type radiating antenna unit according to claim 1, characterized in that: The following steps are involved: Processing electrical connection holes on the green porcelain tape forming the middle cavity layer and the base feed network structure layer, filling the electrical connection holes on the green porcelain tape with gold paste, forming interconnection metallized holes after drying, and then printing conductor printed patterns on part of the green porcelain tape and drying; Processing exhaust holes and radiation patch conductor patterns on the raw porcelain tape forming the top radiation unit structure layer, processing exhaust channel holes on part of the raw porcelain tape forming the middle cavity layer, processing built-in cavity holes on the raw porcelain tape forming the middle cavity layer, processing outer cavity holes on the raw porcelain tape forming the middle cavity layer and the base feed network structure layer; Laminating the raw porcelain tapes forming the base feed network structure layer to form a base blank; Prepare sacrificial materials and inlay molds; laminate raw porcelain tapes with built-in cavity holes and interconnected metallized holes on the base blank layer by layer, fill sacrificial materials in each layer of built-in cavity holes layer by layer, and then laminate raw porcelain tapes with exhaust channel holes layer by layer; then place the inlay mold into the outer cavity formed by the outer cavity holes to form the antenna unit blank; The antenna unit blank is sealed and isostatically laminated, and the laminated antenna unit blank is co-sintered to obtain a built-in cavity type radiation antenna unit.

3. The method for preparing a built-in cavity type radiating antenna unit according to claim 2, characterized in that: The sacrificial material is first prepared into a filling blank and then filled into the built-in cavity hole layer by layer.

4. The method for preparing a built-in cavity type radiating antenna unit according to claim 2, characterized in that: The sacrificial material is propylene carbonate, and the propylene carbonate is prepared into a filling blank by hot pressing. The temperature of the hot pressing is 60-90° C., and the pressure of the hot pressing is 12-20 MPa.

5. The method for preparing a built-in cavity type radiating antenna unit according to claim 2, characterized in that: The exhaust holes, exhaust channel holes, built-in cavity holes and outer cavity holes are laser processed by ultraviolet laser, the power of laser processing is 4.2-5W, the pulse frequency of laser processing is 60-80KHz, and the laser cutting speed of laser processing is 800mm / s.

6. The method for preparing a built-in cavity type radiating antenna unit according to claim 2, characterized in that: The lamination temperature for laminating the raw porcelain tape forming the base feed network structure layer is 50~80°C, the pressure is 2000~2500psi, and the pressure holding time is 8~15min.

7. The method for preparing a built-in cavity type radiating antenna unit according to claim 2, characterized in that: The single piece thickness of all raw ceramic tiles is 114um and the size is 8 inches.

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