Withering Mode Micromechanical Filter

Abstract

The present invention provides a micromechanical filter with a decay mode structure, belonging to the field of semiconductor packaging technology, comprising an upper dielectric layer and a lower dielectric layer, wherein the upper dielectric layer is provided with an upper grounding metallized through hole, a signal feed-in part and a signal feed-out part; the lower dielectric layer is bonded to the bottom of the upper dielectric layer, and the lower dielectric layer is provided with a lower grounding metallized through hole and a lower electromagnetic shielding metallized through hole, and the lower electromagnetic shielding metallized through hole serves as a decay mode resonant column; the signal feed-in part and the signal feed-out part are not physically connected to the decay mode resonant column; the upper dielectric layer and the lower dielectric layer are grounded together through the upper grounding metallized through hole and the lower grounding metallized through hole. The present invention combines the decay mode structure with a micromechanical filter, applies the MEMS process to the decay mode structure, and deforms and reconstructs the resonant coupling structure, and has the characteristics of narrow bandwidth and ultra-wideband comprehensive coverage, small size, high phase consistency, far harmonic suppression, and high Q value.

Description

Technical Field

[0001] The invention belongs to the technical field of semiconductor packaging, and in particular relates to a withering mode structure micromechanical filter. Background Art

[0002] With the development of 5G communication technology, the system has higher and higher requirements for microwave filters (because the filter plays the role of frequency selection filtering as a core device), so a structural form is needed that can achieve both narrow bandwidth and ultra-wide bandwidth when necessary, and it has the advantages of small size, high Q value, high phase consistency, and long harmonic suppression. As a mass application product, it must be easy to produce and low in cost. The traditional dielectric cavity filters, LC filters, metal cavity filters, MEMS microstrip filters, LTCC filters and bulk acoustic filters that are currently widely used are difficult to meet the requirements, so filters that achieve the above characteristics will be the focus of future communication technology development.

[0003] Semiconductor technology has the advantages of high precision and good repeatability, but the microstrip line filters made with it have always had disadvantages such as low Q value, simple structure, and low rectangularity, which limit its scope of use and fail to give full play to the advantages of semiconductor technology. Summary of the invention

[0004] The embodiment of the present invention provides a withering mode structure micromechanical filter, aiming to solve the defects proposed by the prior art and achieve the characteristics of narrow bandwidth and ultra-wideband comprehensive coverage, small size, high phase consistency, far harmonic suppression, and high Q value.

[0005] To achieve the above object, the technical solution adopted by the present invention is: to provide a decay mode structure micromechanical filter, comprising:

[0006] An upper dielectric layer, provided with an upper grounding metallized through hole, a signal feed-in portion, and a signal feed-out portion; and

[0007] A lower dielectric layer is stacked and bonded to the bottom of the upper dielectric layer, the lower dielectric layer is provided with a lower grounding metallized through hole and a lower electromagnetic shielding metallized through hole, and the lower electromagnetic shielding metallized through hole serves as a decay mode resonant column; the signal feeding part and the signal feeding part are not physically connected to the decay mode resonant column;

[0008] The upper dielectric layer and the lower dielectric layer are grounded together through the upper grounding metallization through hole and the lower grounding metallization through hole;

[0009] The microwave signal is input along the signal feeding portion located in the upper dielectric layer, resonated and filtered by the withering mode resonant column of the lower dielectric layer, and then transmitted from the signal feeding portion of the upper dielectric layer.

[0010] In a possible implementation, the upper dielectric layer includes an upper silicon wafer and an upper upper surface metallization pattern and an upper lower surface metallization pattern arranged on the upper surface and the lower surface thereof, the upper upper surface metallization pattern includes the signal feed-in portion, the shielding metal layer and the signal feed-out portion, and the shielding metal layer is connected between the signal feed-in portion and the signal feed-out portion; the upper lower surface metallization pattern includes an upper lower surface electromagnetic shielding metallization frame and an upper lower surface capacitive loading plate isolated from the upper lower surface electromagnetic shielding metallization frame; the upper grounding metallization through hole penetrates the upper silicon wafer, the upper upper surface metallization pattern and the upper lower surface metallization pattern;

[0011] The lower dielectric layer includes a lower wafer silicon wafer and a lower upper surface metallization pattern and a lower lower surface metallization pattern arranged on the upper surface and lower surface thereof, the lower upper surface metallization pattern includes a lower upper surface electromagnetic shielding metallization frame and a lower upper surface capacitive loading plate isolated from the lower upper surface electromagnetic shielding metallization frame; the upper lower surface electromagnetic shielding metallization frame matches the lower upper surface electromagnetic shielding metallization frame, the upper lower surface capacitive loading plate matches the lower upper surface capacitive loading plate, the lower upper surface metallization pattern is bonded to the upper lower surface metallization pattern, so that the upper dielectric layer is bonded to the lower dielectric layer; the lower grounding metallization through hole and the decay mode resonant column both penetrate the lower wafer silicon wafer, the lower upper surface metallization pattern and the lower lower surface metallization pattern.

[0012] In a possible implementation, the upper surface metallization pattern of the upper layer further includes matching branches respectively matching the signal feeding part and the signal feeding part;

[0013] The signal feeding part comprises a signal feeding line and a first grounding line part symmetrically arranged on both sides of the signal feeding line along a first direction;

[0014] The signal feeding portion comprises a signal feeding line and a second grounding line portion symmetrically arranged on both sides of the signal feeding line along the first direction;

[0015] The microwave signal is input from the signal feed line, passes through the corresponding matching branch and the shielding metal layer, is electromagnetically coupled through the decay mode resonant column of the lower dielectric layer, is matched through the matching branch on the opposite side, and is output from the signal feed line.

[0016] In a possible implementation, the lower dielectric layer is provided with a plurality of groups of resonance units, the plurality of groups of resonance units are symmetrical along the second direction of the lower dielectric layer, each group of the resonance units includes a plurality of decay mode resonance columns, wherein each group of the resonance units corresponds to a capacitive loading plate on the upper surface of the lower layer.

[0017] In a possible implementation, the spacing between the groups of resonance units can be adjusted according to port matching and bandwidth requirements.

[0018] In a possible implementation manner, the number of the withering mode resonant columns in each group of the resonant units is the same.

[0019] In a possible implementation, the number of withering mode resonant columns in at least one group of the resonant units is different from that in the other groups.

[0020] In a possible implementation, in each group of the resonance units, the intervals between the withering mode resonance columns are different, and the number and layout of the withering mode resonance columns in the symmetrically arranged resonance units are the same.

[0021] In a possible implementation, each group of the resonance units has a 360° rotational freedom within a horizontal plane where the lower dielectric layer is located.

[0022] In a possible implementation, the size of each of the capacitive loading sheets on the upper surface of the lower layer has different outer dimensions according to the different spacings and quantities of the corresponding different groups of the withering mode resonant columns.

[0023] Compared with the prior art, the extinction mode structure micromechanical filter provided by the present invention has the beneficial effect that there is no physical connection between the upper feeding part and the lower extinction mode resonant column, that is, it is not directly connected through the structure, but through the resonance principle of the electromagnetic extinction mode, the transmission path of the upper microwave signal is changed and transmitted to the lower electromagnetic extinction mode resonant column. After resonance filtering, the transmission path is changed again and uploaded to the upper feeding part, thereby completing the filtering function.

[0024] Among them, by adjusting the number of depletion mode resonant columns, the spacing between them, the arrangement direction, etc., the coupling amount between the depletion mode resonant columns is adjusted, so as to achieve extremely narrow and extremely wide performance of the filter, which can realize high-performance microwave, especially micromechanical filters, and is conducive to the miniaturization and modularization of 5G communication systems, reducing system costs.

[0025] The present invention combines the extinction mode structure with a micromechanical filter, applies the MEMS process to the extinction mode structure, and deforms and reconstructs the resonant coupling structure, which can improve the performance of the product; the micromechanical filter of the extinction mode structure has the characteristics of narrow bandwidth and ultra-wideband comprehensive coverage, small size, high phase consistency, far harmonic suppression, and high Q value. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of the exploded structure of a withering mode structure micromechanical filter provided by an embodiment of the present invention;

[0027] Figure 2 A schematic diagram of the three-dimensional structure of a withering mode structure micromechanical filter provided by an embodiment of the present invention;

[0028] Figure 3 for Figure 2 A schematic diagram of the local structure of a withering mode structure micromechanical filter is provided;

[0029] Figure 4 A schematic diagram of the structure of the upper surface metallization pattern provided by an embodiment of the present invention;

[0030] Figure 5 A schematic diagram of the structure of an upper silicon wafer used in an embodiment of the present invention;

[0031] Figure 6 A schematic diagram of the structure of the upper layer lower surface metallization pattern used in an embodiment of the present invention;

[0032] Figure 7 A schematic diagram of the structure of the metallization pattern on the upper surface of the lower layer used in an embodiment of the present invention;

[0033] Figure 8 A schematic diagram of the structure of a lower silicon wafer used in an embodiment of the present invention;

[0034] Fig. 9 A schematic diagram of the structure of the lower surface metallization pattern of the lower layer adopted in an embodiment of the present invention;

[0035] Description of reference numerals:

[0036] 1. Upper dielectric layer;

[0037] 11. upper surface metallization pattern of the upper layer; 111. signal feed part; 1111. signal feed line; 1112. first ground line part; 112. shielding metal layer; 113. signal feed part; 1131. signal feed line; 1132. second ground line part; 114. matching branch;

[0038] 12. Upper silicon wafer;

[0039] 13. Metallized pattern on the lower surface of the upper layer; 131. Electromagnetic shielding metallized frame on the lower surface of the upper layer; 132. Capacitive loading sheet on the lower surface of the upper layer;

[0040] 14. Upper ground metallization through hole;

[0041] 2. Lower dielectric layer;

[0042] 21. Metallized pattern on the upper surface of the lower layer; 211. Electromagnetic shielding metallized frame on the upper surface of the lower layer; 212. Capacitive loading sheet on the upper surface of the lower layer;

[0043] 22. Lower layer wafer silicon wafer; 23. Lower layer lower surface metallization pattern; 24. Lower layer grounding metallization through hole; 25. Withering mode resonant column; 26. Resonant unit. DETAILED DESCRIPTION

[0044] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0045] In the description of the present invention, it should be noted that if terms such as "front", "rear", "left" and "right" appear to indicate directions or positional relationships, they are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description. They 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, they cannot be understood as limitations on the present invention.

[0046] Please also read Figures 1 to 9 , the extinction mode structure micromechanical filter provided by the present invention is now described. The extinction mode structure micromechanical filter comprises: an upper dielectric layer 1 and a lower dielectric layer 2, wherein the upper dielectric layer 1 is provided with an upper grounding metallized through hole 14, a signal feeding part 111 and a signal feeding part 113; the lower dielectric layer 2 is stacked and bonded to the bottom of the upper dielectric layer 1, and the lower dielectric layer 2 is provided with a lower grounding metallized through hole 24 and a lower electromagnetic shielding metallized through hole, and the lower electromagnetic shielding metallized through hole serves as a extinction mode resonant column 25; the signal feeding part 111 and the signal feeding part 113 are not physically connected to the extinction mode resonant column 25; the upper dielectric layer 1 and the lower dielectric layer 2 are grounded together through the upper grounding metallized through hole 14 and the lower grounding metallized through hole 24; the microwave signal is input along the signal feeding part 111 located in the upper dielectric layer 1, resonated and filtered through the extinction mode resonant column 25 of the lower dielectric layer, and then transmitted from the signal feeding part 113 of the upper dielectric layer 1.

[0047] Compared with the prior art, the extinction mode structure micromechanical filter provided in the present embodiment has no physical connection between the upper feeding part and the lower extinction mode resonant column 25, that is, it is not directly connected through the structure, but through the resonance principle of the electromagnetic extinction mode, the transmission path of the upper microwave signal is changed and transmitted to the lower electromagnetic extinction mode resonant column 25. After resonance filtering, the transmission path is changed again and uploaded to the upper feeding part, thereby completing the filtering function.

[0048] Among them, by adjusting the number, spacing, arrangement direction, etc. of the withering mode resonant columns 25, the coupling amount between the withering mode resonant columns 25 is adjusted, so as to achieve extremely narrow and extremely wide performance of the filter, which can realize high-performance microwave, especially micromechanical filters, and is conducive to the miniaturization and modularization of 5G communication systems, reducing system costs.

[0049] The present invention combines the extinction mode structure with a micromechanical filter, applies the MEMS process to the extinction mode structure, and deforms and reconstructs the resonant coupling structure, which can improve the performance of the product; the micromechanical filter of the extinction mode structure has the characteristics of narrow bandwidth and ultra-wideband comprehensive coverage, small size, high phase consistency, far harmonic suppression, and high Q value.

[0050] As a specific implementation of the decay mode structure micromechanical filter provided in this embodiment, see Figures 1 to 6 The upper dielectric layer 1 includes an upper silicon wafer 12 and an upper upper surface metallization pattern 11 and an upper lower surface metallization pattern 13 arranged on the upper surface and the lower surface thereof, the upper upper surface metallization pattern 11 includes a signal feeding part 111, a shielding metal layer 112 and a signal feeding part 113, and the shielding metal layer 112 is connected between the signal feeding part 111 and the signal feeding part 113; the upper lower surface metallization pattern 13 includes an upper lower surface electromagnetic shielding metallization frame 131 and an upper lower surface capacitive loading sheet 132 isolated from the upper lower surface electromagnetic shielding metallization frame 131; the upper grounding metallization through hole 14 penetrates the upper silicon wafer 12, the upper upper surface metallization pattern 11 and the upper lower surface metallization pattern 13.

[0051] See also Figures 7 to 9The lower dielectric layer 2 includes a lower wafer silicon wafer 22 and a lower upper surface metallization pattern 21 and a lower lower surface metallization pattern 23 arranged on the upper surface and lower surface thereof, the lower upper surface metallization pattern 21 includes a lower upper surface electromagnetic shielding metallization frame 211 and a lower upper surface capacitive loading sheet 212 isolated from the lower upper surface electromagnetic shielding metallization frame 211; the upper lower surface electromagnetic shielding metallization frame 131 matches the lower upper surface electromagnetic shielding metallization frame 211, the upper lower surface capacitive loading sheet 132 matches the lower upper surface capacitive loading sheet 212, the lower upper surface metallization pattern 21 is bonded to the upper lower surface metallization pattern 13, so that the upper dielectric layer 1 and the lower dielectric layer 2 are bonded; the lower grounding metallization through hole 24 and the decay mode resonant column 25 all penetrate the lower wafer silicon wafer 22, the lower upper surface metallization pattern 21 and the lower lower surface metallization pattern 23.

[0052] In this embodiment, the upper dielectric layer 1 and the lower dielectric layer 2 are both high-resistance silicon dielectrics. The specific examples are as follows: the upper silicon wafer 12 is 100 μm thick and is made from a standard 250 μm thick silicon wafer through polishing, thinning and surface treatment; the lower silicon wafer 22 is 400 μm thick and is also made from a standard silicon wafer through polishing, thinning and surface treatment. The upper dielectric layer 1 and the lower dielectric layer 2 are packaged through the upper lower surface metallization pattern 13 and the lower upper surface metallization pattern 21 through gold-gold bonding technology, so that the product has the advantages of fully sealed box electromagnetic shielding.

[0053] In this embodiment, the upper dielectric layer 1 and the lower dielectric layer 2 are realized by a gold-gold bonding process, so that the upper and lower dielectric layers are fused together. After the above process is completed, the wafer is cut into small pieces by a dicing process, and the withering mode structure micromechanical filter is completed.

[0054] The embodiment of the present invention is based on the decay mode structure and manufactures a micromechanical filter on a wafer. This method not only innovates the structure, but also takes into account the advantages of semiconductor technology. It can achieve full coverage of narrow bandwidth and ultra-wideband, and has the characteristics of small size, high phase consistency, far harmonic suppression, and high Q value.

[0055] The thickness of the upper layer upper surface metallization pattern 11, the upper layer lower surface metallization pattern 13, the lower layer upper surface metallization pattern 21 and the lower layer lower surface metallization pattern 23 are all 3.5 microns.

[0056] As a specific implementation of the upper surface metallization pattern 11 provided in this embodiment, see Figure 4As shown, the upper surface metallization pattern 11 of the upper layer also includes matching branches 114 that match the signal feed part 111 and the signal feed part 113 respectively; the signal feed part 111 includes a signal feed line 1111 and a first ground line part 1112 symmetrically arranged on both sides of the signal feed line 1111 along the first direction; the signal feed part 113 includes a signal feed line 1131 and a second ground line part 1132 symmetrically arranged on both sides of the signal feed line 1131 along the first direction. Both the signal feed part 111 and the signal feed part 113 adopt a coplanar wave form, consisting of a signal feed line 1111 part and two ground line parts, and the ground line is grounded to the lower dielectric layer 2 through a grounding metallization through hole to achieve a grounding effect. The matching branches 114 connected to the signal feed line 1111 and the signal feed line 1131 realize impedance matching of filters of different frequencies and bandwidths, and at the same time, the matching branches 114 and the lower layer of the decay mode resonant column 25 achieve an electromagnetic coupling effect to form energy transmission. The matching branch 114 is directly connected to the upper shielding metal layer 112 , and the shielding metal layer 112 is connected to the grounding layer of the lower dielectric layer 2 through the metallized through holes at the left and right ends of the upper dielectric layer 1 , so as to achieve a common ground effect.

[0057] The transmission process of the microwave signal is as follows: the microwave signal is input from the signal feed line 1111, passes through the corresponding matching branch 114 and the shielding metal layer 112, changes the transmission direction to transmit downward, is electromagnetically coupled through the decay mode resonant column 25 of the lower dielectric layer 2, then changes the transmission direction to transmit upward, is matched through the matching branch 114 on the opposite side of the upper dielectric layer 1, and is output from the signal feed line 1131. This completes the filtering function.

[0058] As a specific implementation of the lower dielectric layer 2 provided in this embodiment, see Figures 7 to 9 The lower dielectric layer 2 is provided with a plurality of groups of resonance units, which are symmetrical along the second direction of the lower dielectric layer 2, and each group of resonance units includes a plurality of decay mode resonance columns 25, wherein each group of resonance units corresponds to a capacitive loading sheet 212 on the upper surface of the lower layer.

[0059] This embodiment uses Figure 1 For example, the first direction is defined as the left-right direction of the upper dielectric layer 1 and the lower dielectric layer 2 , and the second direction is defined as the front-back direction of the upper dielectric layer 1 and the lower dielectric layer 2 .

[0060] The design concept of the decay mode structure micromechanical filter provided in this embodiment is as follows: Figures 7 to 9, a certain number of metallized through holes are arranged on the lower dielectric layer 2, and these through holes are divided into two types in electromagnetic applications, one is the metallized through hole for electromagnetic shielding, and the other is the through hole for the resonance function involved in product performance. The present application cleverly uses the metallized through hole as the decay mode resonant column 25, which is symmetrically distributed about the second direction, or the center line along the left and right direction of the lower dielectric layer 2, to control the number and position of the holes.

[0061] See also Figures 7 to 9 There are many ways to layout the resonance unit, and the embodiments are set as follows: for example, the change in quantity can be based on specific indicators to set at least two withering mode resonance columns 25 arranged in parallel in the front-to-back direction. No matter how many withering mode resonance columns 25 there are, they all play the role of a resonance unit in the same column; the change in distance, and the distance between equivalent withering mode resonance columns 25 in the same column is variable, that is, it can be adjusted according to port matching and bandwidth requirements, and it is more flexible; the change in the number and distance of different resonance units, the resonators in different rows are equivalent to resonance units, and the coupling between the resonance units can be adjusted by adjusting the number and arrangement direction of the withering mode resonance columns 25 at the same spacing. Based on this change, the performance of extremely narrow and extremely wide bandwidth of the filter can be achieved, and the overall size of the filter can also be unified, breaking the limitation of the limited volume of traditional filters in the past, and achieving product diversity under the condition of unified small size.

[0062] This embodiment sees Figures 7 to 9 , there are four groups of resonance units arranged along the first direction of the lower dielectric layer 2, each group of resonance units has two withering mode resonance columns 25 in parallel in front and back, and the resonance units are symmetrically distributed left and right. The microwave signal transmission process is as follows: the upper signal feeding line 1111 is not physically connected with the lower withering mode resonance rod, but through the resonance principle of the electromagnetic withering mode, the transmission path of the upper microwave signal is changed and transmitted to the lower electromagnetic withering mode resonance column 25, and after filtering through the 4-level resonance rod, the transmission path is changed again and uploaded to the upper signal feeding line 1131, thereby completing the filtering function.

[0063] As an implementation of the layout structure of the resonance unit, see Figures 7 to 9 The spacing between each group of resonant units can be adjusted according to port matching and bandwidth requirements. For example, the spacing between the two groups of resonant units on the left side of the lower dielectric layer 2 can be adjusted.

[0064] As another embodiment of the layout structure of the resonance unit, see Figures 7 to 9, the number of the decay mode resonant columns 25 in each group of resonant units is the same. Two decay mode resonant columns 25 are arranged in parallel in each group of resonant units. In other embodiments, a group of resonant units may have three, four, or the like decay mode resonant columns 25 arranged in parallel, wherein the number of the decay mode resonant columns 25 in each group of resonant units is the same, but the spacings may be the same or different.

[0065] As another embodiment of the layout structure of the resonance unit, see Figures 7 to 9 , the number of decay mode resonant columns 25 in each group of resonant units, at least one group has a number different from the number in other groups. For example, of the two groups of resonant units on the left, the number of decay mode resonant columns 25 in the leftmost group of resonant units is two, and the number of decay mode resonant columns 25 in the group of resonant units near the center is three; the resonant units are symmetrical on the left and right. In this embodiment, the filter can be designed in combination with the adjustment of the spacing between the resonant units.

[0066] As another embodiment of the layout structure of the resonance unit, see Figures 7 to 9 In each group of resonance units, the spacing between the decay mode resonance columns 25 is different, and the number and layout of the decay mode resonance columns 25 in the symmetrically arranged resonance units are the same.

[0067] As another embodiment of the layout structure of the resonance unit, each group of resonance units has a 360° rotational freedom in the horizontal plane where the lower dielectric layer 2 is located. For example, each group of resonance units rotates 90° counterclockwise or clockwise at the angle shown in the figure. For another example, it can also rotate 45° clockwise or counterclockwise.

[0068] The layout embodiments of the above-mentioned resonance units all have their own emphasis, and in actual design, they can be used separately or in combination.

[0069] Since the number, spacing, etc. of the decay mode resonant columns 25 in each resonant unit may be different, as a specific implementation method, see Figures 1 to 3 , Figure 6 and Figure 7 The size of the capacitive loading piece 212 on the upper surface of each lower layer has different outer dimensions according to the different spacings and numbers of the corresponding different groups of decay mode resonant columns 25. This embodiment corresponds to four groups of resonant units, and each corresponding layer is provided with four capacitive loading pieces. By bonding the corresponding metal frame and the corresponding capacitive loading piece, the reliability of the bonding of the upper and lower dielectric layers 2 is improved, and the risk of peeling is reduced.

[0070] As a specific implementation of the upper surface metallization pattern 11 provided in this embodiment, see Figures 1 to 9, multiple upper-layer grounding metallized through holes 14 are symmetrically arranged in the front and back and left and right of the upper dielectric layer 1, wherein the upper-layer grounding metallized through holes 14 arranged in the front and back penetrate the shielding metal layer 112, and the upper-layer grounding metallized through holes 14 arranged in the left and right correspondingly penetrate the first grounding wire part 1112 and the second grounding wire part 1132; multiple lower-layer grounding metallized through holes 24 are symmetrically arranged in the front and back of the lower dielectric layer 2, and the upper-layer grounding metallized through holes 14 and the lower-layer grounding metallized through holes 24 are not completely vertically interconnected. That is, some of the metallized through holes can be vertical, and some of the metallized through holes can be non-vertical.

[0071] The upper-layer grounding metallized through hole 14 is a circular hole, and the lower-layer grounding metallized through hole 24 and the lower-layer electromagnetic shielding metallized through hole serving as the resonant column are oblong holes.

[0072] In summary, this example uses two grounding holes as equivalent resonant units. By controlling the relative positions of the two grounding holes (i.e., the decay mode resonant column), the coupling between adjacent resonant units can be adjusted. The decay mode resonant column at the feed-in end and the decay mode resonant column at the feed-out end are spaced relatively large, and are located at the edges of the cavity surrounded by the metallized frame. In actual design, the direction of the decay mode resonant column can also be rotated by an angle, that is, rotated to 90° at the current angle, so that a wider bandwidth can be achieved.

[0073] The decay mode resonant column of this embodiment is realized by an etching process, and the size of the lower electromagnetic shielding metallized through hole is 250×120×400mm. This application utilizes standardized grounding holes to design electromagnetic shielding metallized through holes to reduce production costs and process difficulties; secondly, combined with micro-mechanical technology, it can accurately produce graphics, achieve stable product performance and phase consistency of batch products; thirdly, the flexible arrangement of the resonant unit makes it difficult to achieve coupling of the filter parasitic passband, and has the characteristics of ultra-long parasitics, which also has the characteristics of achieving long-range harmonic suppression.

[0074] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A withering mode structure micromechanical filter, characterized in that: include: An upper dielectric layer (1) is provided with an upper grounding metallized through hole (14), a signal feed-in portion (111) and a signal feed-out portion (113); as well as A lower dielectric layer (2) is stacked and bonded below the upper dielectric layer (1), the lower dielectric layer (2) being provided with a lower grounding metallized through hole (24) and a lower electromagnetic shielding metallized through hole, the lower electromagnetic shielding metallized through hole serving as a decay mode resonant column (25); the signal feed-in portion (111) and the signal feed-out portion (113) are not physically connected to the decay mode resonant column (25); The upper dielectric layer (1) and the lower dielectric layer (2) are connected to a common ground via the upper grounding metallized through hole (14) and the lower grounding metallized through hole (24); The microwave signal is input along the signal feeding portion (111) located in the upper dielectric layer (1), resonated and filtered by the decay mode resonant column (25) of the lower dielectric layer, and then transmitted from the signal feeding portion (113) of the upper dielectric layer (1); The upper dielectric layer (1) comprises an upper silicon wafer (12) and an upper upper surface metallization pattern (11) and an upper lower surface metallization pattern (13) arranged on the upper surface and the lower surface thereof, the upper upper surface metallization pattern (11) comprising the signal feed-in portion (111), a shielding metal layer (112) and the signal feed-out portion (113), the shielding metal layer (112) being connected between the signal feed-in portion (111) and the signal feed-out portion (113); the upper lower surface metallization pattern (13) comprising an upper lower surface electromagnetic shielding metallization frame (131) and an upper lower surface capacitive loading plate (132) isolated from the upper lower surface electromagnetic shielding metallization frame (131); the upper grounding metallization through hole (14) passes through the upper silicon wafer (12), the upper upper surface metallization pattern (11) and the upper lower surface metallization pattern (13); The lower dielectric layer (2) comprises a lower silicon wafer (22) and a lower upper surface metallization pattern (21) and a lower lower surface metallization pattern (23) arranged on the upper surface and the lower surface thereof, wherein the lower upper surface metallization pattern (21) comprises a lower upper surface electromagnetic shielding metallization frame (211) and a lower upper surface capacitive loading sheet (212) isolated from the lower upper surface electromagnetic shielding metallization frame (211); the upper lower surface electromagnetic shielding metallization frame (131) matches the lower upper surface electromagnetic shielding metallization frame (2 11), the upper layer lower surface capacitive loading piece (132) matches the lower layer upper surface capacitive loading piece (212), the lower layer upper surface metallization pattern (21) is bonded to the upper layer lower surface metallization pattern (13), so that the upper dielectric layer (1) and the lower dielectric layer (2) are bonded; the lower layer grounding metallization through hole (24) and the decay mode resonant column (25) both penetrate the lower layer wafer silicon sheet (22), the lower layer upper surface metallization pattern (21) and the lower layer lower surface metallization pattern (23).

2. The withering mode structure micromechanical filter according to claim 1, characterized in that: The upper surface metallization pattern (11) further comprises matching branches (114) respectively matching the signal feeding portion (111) and the signal feeding portion (113); The signal feeding part (111) comprises a signal feeding line (1111) and a first grounding line part (1112) symmetrically arranged on both sides of the signal feeding line (1111) along a first direction; The signal feeding part (113) comprises a signal feeding line (1131) and a second grounding line part (1132) symmetrically arranged on both sides of the signal feeding line (1131) along the first direction; The microwave signal is input from the signal feed line (1111), passes through the corresponding matching branch (114) and the shielding metal layer (112), is electromagnetically coupled through the decay mode resonant column (25) of the lower dielectric layer (2), is matched through the matching branch (114) on the opposite side, and is output from the signal feed line (1131).

3. The withering mode structure micromechanical filter according to claim 1, characterized in that: The lower dielectric layer (2) is provided with a plurality of groups of resonance units, the plurality of groups of resonance units are symmetrical along the second direction of the lower dielectric layer (2), each group of the resonance units comprises a plurality of decay mode resonance columns (25), wherein each group of the resonance units corresponds to a capacitive loading plate (212) on the upper surface of the lower layer.

4. The withering mode structure micromechanical filter according to claim 3, characterized in that: The spacing between the resonant units in each group can be adjusted according to port matching and bandwidth requirements.

5. The withering mode structure micromechanical filter according to claim 3, characterized in that: The number of the decay mode resonance columns (25) in each group of the resonance units is the same.

6. The withering mode structure micromechanical filter according to claim 3, characterized in that: The number of the decay mode resonance columns (25) in each group of the resonance units is different from that in the other groups in at least one group.

7. The withering mode structure micromechanical filter according to claim 3, characterized in that: In each group of the resonance units, the spacings between the decay mode resonance columns (25) are different, and the number and layout of the decay mode resonance columns (25) in the symmetrically arranged resonance units are the same.

8. The withering mode structure micromechanical filter according to claim 3, characterized in that: Each group of the resonant units has a 360° rotational freedom within the horizontal plane where the lower dielectric layer (2) is located.

9. The withering mode structure micromechanical filter according to claim 3, characterized in that: The size of each of the capacitive loading sheets (212) on the upper surface of the lower layer has different outer dimensions according to the different spacings and quantities of the corresponding different groups of the decay mode resonant columns (25).

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