Micromechanical switch and antenna

Abstract

The invention relates to the technical field of communication, and discloses a micromechanical switch and an antenna. The micromechanical switch comprises a dielectric substrate; the first reference electrode, the second reference electrode and the signal electrode are arranged on the dielectric substrate, and the first reference electrode comprises a plurality of first sub-reference electrodes which are arranged in the extending direction of the first reference electrode in a disconnected mode; the film bridge is arranged on one side, deviating from the dielectric substrate, of a layer where the signal electrode, the first reference electrode and the second reference electrode are located; the first sub reference electrode comprises a main body structure and a contact structure connected to the main body structure, the orthographic projection of the bridge surface structure of the film bridge and the orthographic projection of the contact structure on the dielectric substrate are at least partially overlapped, and the orthographic projection of the bridge surface structure of the film bridge and the orthographic projection of the main body structure on the dielectric substrate are not overlapped. Through the scheme of the invention, the contact area of the membrane bridge and the first sub reference electrode is reduced, the problem of collapse of the bridge floor structure of the membrane bridge caused by large contact area is solved, the deformation of the bridge floor structure of the membrane bridge is effectively weakened, and the working stability of the micro mechanical switch is improved.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to a micromechanical switch and an antenna. Background Art

[0002] With the development of communication technology, more and more frequency bands are used in communication technology. In order to meet the needs of each frequency band at the same time, the number of antennas in smart terminals has also increased. For this reason, frequency-reconfigurable antennas have attracted attention. Based on micromechanical RF switches, frequency-reconfigurable antennas can be constructed. When no voltage is applied, the cantilever beam of the micromechanical RF switch is in a suspended state. When voltage is applied, the cantilever beam collapses to connect the separated metal sheets of the micromechanical RF switch. However, during operation, the micromechanical RF switch has problems such as high driving voltage, easy collapse of the cantilever beam, or failure of the micromechanical switch due to local abnormal contact. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art and provides a micromechanical switch and an antenna.

[0004] An aspect of an embodiment of the present invention provides a micromechanical switch, specifically comprising:

[0005] dielectric substrate;

[0006] A first reference electrode and a second reference electrode are arranged on the dielectric substrate, and the first reference electrode includes a plurality of first sub-reference electrodes that are arranged in a disconnected manner along an extending direction thereof;

[0007] A signal electrode is disposed on the dielectric substrate, and an orthographic projection of at least a portion of the signal electrode on the dielectric substrate is located between the orthographic projections of the first reference electrode and the second reference electrode on the dielectric substrate;

[0008] A membrane bridge is arranged on a side of the layer where the signal electrode, the first reference electrode and the second reference electrode are located away from the dielectric substrate, and there is a certain distance between the bridge surface structure of the membrane bridge and the signal electrode, and the orthographic projections of the two on the dielectric substrate at least partially overlap; wherein,

[0009] The first sub-reference electrode includes a main structure and a contact structure connected to the main structure, and the bridge deck structure of the membrane bridge and the orthographic projection of the contact structure on the dielectric substrate at least partially overlap, and the bridge deck structure of the membrane bridge and the orthographic projection of the main structure on the dielectric substrate do not overlap.

[0010] In some embodiments, the main structure has a notch facing the second reference electrode, and the contact structure is connected in the notch and extends toward the second reference electrode;

[0011] The signal electrode has a plurality of grooves, and an orthographic projection of one of the contact structures on the dielectric substrate is located within an orthographic projection of one of the grooves on the dielectric substrate.

[0012] In some embodiments, for any adjacent first sub-reference electrodes, the contact structure is located between the areas defined by two of the main structures;

[0013] The signal electrode has a plurality of grooves, and an orthographic projection of one of the contact structures on the dielectric substrate is located within an orthographic projection of one of the grooves on the dielectric substrate.

[0014] In some embodiments, the first sub-reference electrode includes at least one of the contact structures.

[0015] In some embodiments, the bridge deck structure has a hollow pattern; the hollow pattern has no overlap with the orthographic projection of the first sub-reference electrode on the dielectric substrate.

[0016] In some implementations, the hollowed-out image has no overlap with an orthographic projection of the signal electrode on the dielectric substrate.

[0017] In some embodiments, the bridge deck structure includes a first part and a second part that are relatively connected, and the second part is connected to the support arm of the membrane bridge; the orthographic projection of the first part on the dielectric substrate covers the orthographic projection of the signal electrode on the dielectric substrate, and the second part has no overlap with the orthographic projection of the signal electrode on the dielectric substrate; wherein the width of the second part along the extension direction of the second reference electrode is smaller than the width of the first part along the extension direction of the second reference electrode.

[0018] In some embodiments, the support arm of the membrane bridge is located on a side of the second reference electrode facing away from the dielectric substrate, and is directly connected to the second reference electrode.

[0019] In some embodiments, the second reference electrode includes: a second sub-reference electrode and a third sub-reference electrode which are stacked, and the third sub-reference electrode is located on a side of the second sub-reference electrode away from the dielectric substrate;

[0020] The supporting arm of the membrane bridge is located at a side of the third sub-reference electrode away from the dielectric substrate.

[0021] In some embodiments, an interlayer insulating layer is disposed on a side of the signal electrode facing away from the dielectric substrate, and the first reference electrode and the second reference electrode are disposed on a side of the interlayer insulating layer facing away from the dielectric substrate.

[0022] In some embodiments, a first contact structure is provided on a side of the first reference electrode close to the membrane bridge, and a second contact structure is provided on a side of the bridge deck structure close to the first reference electrode, and the first contact structure and the second contact structure are provided correspondingly.

[0023] Another aspect of the embodiments of the present invention further provides an antenna, comprising: a micromechanical switch as described in any of the above embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other embodiments can be obtained based on these drawings without paying creative work.

[0025] Figure 1 A schematic diagram of the structure of a micromechanical switch provided by the present invention;

[0026] Figure 2 A schematic diagram of the structure of a micromechanical switch provided by the present invention, in which the membrane bridge is not shown;

[0027] Figure 3 for Figure 1 A cross-sectional view of a micromechanical switch;

[0028] Figure 4 for Figure 1 A cross-sectional view of a micromechanical switch;

[0029] Figure 5 A schematic diagram of the structure of a membrane bridge provided by the present invention;

[0030] Figure 6 A schematic diagram of the structure of a micromechanical switch provided by the present invention;

[0031] Figure 7 A schematic diagram of the structure of a micromechanical switch provided by the present invention, in which the membrane bridge is not shown;

[0032] Figure 8 for Figure 6 A cross-sectional view of a micromechanical switch;

[0033] FIG. 9A to FIG. 9D A schematic diagram of the structure of a signal electrode of a micromechanical switch provided by the present invention;

[0034] Figure 10A to Figure 10C A schematic structural diagram of a bridge deck structure of a micromechanical switch provided by the present invention. DETAILED DESCRIPTION

[0035] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the embodiments of the present invention are further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0036] It should be noted that all expressions using "first" and "second" in the embodiments of the present invention are for distinguishing two non-identical entities with the same name or non-identical parameters. It can be seen that "first" and "second" are only for the convenience of expression and should not be understood as limitations on the embodiments of the present invention. The subsequent embodiments will not explain this one by one.

[0037] According to a first aspect of an embodiment of the present invention, a micromechanical switch is provided.

[0038] Figure 1 Schematic diagram of the structure of a micromechanical switch. Figure 4 It is a schematic diagram of the structure of a micromechanical switch whose membrane bridge is not shown. Figure 2 for Figure 1 A cross-sectional view of a micromechanical switch. Figure 3 for Figure 1 A cross-sectional view of a micromechanical switch. Specifically, Figure 2 The cross-sectional view is Figure 1 The cross-sectional view of the micromechanical switch along the A-A' direction, Figure 3 The cross-sectional view is Figure 1 Cross-sectional view of the micromechanical switch along the BB' direction.

[0039] Reference Figure 1 to Figure 4 The micromechanical switch specifically comprises: a dielectric substrate 10, a first reference electrode 20, a second reference electrode 30, a signal electrode 40 and a membrane bridge 50; the first reference electrode 20 and the second reference electrode 30 are arranged on the dielectric substrate 10, and the first reference electrode 20 comprises a plurality of first sub-reference electrodes 21 which are arranged in a disconnected manner along the extension direction thereof; the signal electrode 40 is arranged on the dielectric substrate 10, and at least a part of the signal electrode 40 is located between the orthographic projections of the first reference electrode 20 and the second reference electrode 30 on the dielectric substrate 10; the membrane bridge 50 is arranged on the signal electrode The layer where the electrode 40, the first reference electrode 20 and the second reference electrode 30 are located is away from the side of the dielectric substrate, and there is a certain distance between the bridge deck structure 51 of the membrane bridge 50 and the signal electrode 40, and the orthographic projections of the two on the dielectric substrate 10 at least partially overlap; the first sub-reference electrode 21 includes a main structure 210, and a contact structure 220 connected to the main structure 210, and the orthographic projections of the bridge deck structure 51 of the membrane bridge 50 and the contact structure 220 on the dielectric substrate 10 at least partially overlap, and the orthographic projections of the bridge deck structure 51 of the membrane bridge 50 and the main structure 210 on the dielectric substrate 10 do not overlap.

[0040] In the disclosed embodiment, the second reference electrode is in direct contact with the membrane bridge, and the structures of the two may be integrated.

[0041] In the disclosed embodiment, when the micromechanical switch is working, by applying driving voltages of different magnitudes to the second reference electrode and the signal electrode respectively, the membrane bridge directly in contact with the second reference electrode has a driving voltage close to that of the second reference electrode, thereby generating an electrostatic force between the signal electrode and the bridge surface structure of the membrane bridge. Under the action of the electrostatic force, the bridge surface structure moves toward the direction of the signal electrode until it contacts the contact structure of the multiple first sub-reference electrodes in the first reference electrode, thereby achieving conduction of the multiple first sub-reference electrodes.

[0042] In some examples, the voltage applied to the signal electrode is greater than the voltage applied to the second reference electrode, thereby ensuring that the bridge structure can move toward the signal electrode under the action of electrostatic force and eventually contact the contact structure of the first sub-reference electrode.

[0043] The disclosed embodiment reduces the contact area between the membrane bridge and the first sub-reference electrode by making the bridge deck structure of the membrane bridge contact with the contact structure of the first sub-reference electrode, thereby helping to solve the problem of collapse of the bridge deck structure of the membrane bridge caused by the large contact area between the membrane bridge and the first sub-reference electrode, effectively weakening the deformation of the bridge deck structure of the membrane bridge and improving the stability of the operation of the micromechanical switch.

[0044] In some embodiments, the signal electrode is connected to a first driving signal line, which runs through the adjacent first sub-reference electrode. The second reference electrode is connected to a second driving signal line, which extends toward the first sub-reference electrode.

[0045] In some embodiments, Figure 4 As shown, Figure 1 The schematic diagram of the structure of the first sub-reference electrode, the signal electrode and the second reference electrode of the micromechanical switch shown. The main structure 210 of the first sub-reference electrode 21 has a notch 211 facing the second reference electrode 30. The contact structure 220 of the first sub-reference electrode 21 is connected in the notch 211 and extends toward the second reference electrode 30. The signal electrode 40 has a plurality of grooves 410, and the orthographic projection of one contact structure 220 on the dielectric substrate 10 is located within the orthographic projection of one groove 410 on the dielectric substrate 10.

[0046] In some examples, the signal electrode includes an extension portion at an end facing away from the second reference electrode, the extension portion of the signal electrode includes a first portion and a second portion that are relatively connected, the orthographic projection of the first portion of the extension portion on the dielectric substrate overlaps with the first sub-reference electrode, and the orthographic projection of the second portion of the extension portion on the dielectric substrate does not overlap with the first sub-reference electrode; the groove 410 is located in the first portion of the extension portion, and the orthographic projection of a contact structure 220 of the first sub-reference electrode 21 on the dielectric substrate is located within the orthographic projection of a groove 410 on the dielectric substrate.

[0047] In the embodiment of the present disclosure, the first sub-reference electrode is obtained by patterning the metal film layer where the first sub-reference electrode is located, the sidewall of the groove portion formed by patterning is the contact structure of the first sub-reference electrode, and the opening of the groove portion is the notch of the main structure. The signal electrode is obtained by patterning the metal film layer where the signal electrode is located, the opening of the groove portion formed by patterning is the groove of the signal electrode, and the groove corresponds to the shape and position of the contact structure.

[0048] In some examples, the first sub-reference electrode and the signal electrode may be located in the same metal film layer, or may be located in different metal film layers.

[0049] In the embodiments of the present disclosure, by patterning the metal film layer where the first sub-reference electrode and the signal electrode are located, the contact area between the first sub-reference electrode and the bridge deck structure of the membrane bridge is reduced when the micromechanical switch is working, thereby helping to solve the problem of collapse of the bridge deck structure of the membrane bridge caused by the large contact area between the membrane bridge and the first sub-reference electrode; by patterning the metal film layer where the signal electrode is located, the overlapping area between the signal electrode and the bridge deck structure of the membrane bridge is increased, thereby reducing the driving voltage; the above scheme effectively reduces the deformation of the bridge deck structure of the membrane bridge and improves the working stability of the micromechanical switch.

[0050] In some examples, in order to ensure that the bridge deck structure of the membrane bridge can overlap with the signal electrode and avoid lithography and process deviations when patterning the signal electrode, such as Figure 2 As shown, the signal electrode 40 also has an extension structure 420, which is located at one end of the signal electrode 40 away from the second reference electrode 30. More specifically, the extension structure 420 is located in the second part of the extension portion of the signal electrode, and the extension structure 420 has no overlap with the orthographic projection of the bridge deck structure of the membrane bridge on the dielectric substrate.

[0051] In some examples, the length of the extension structure in a direction away from the second reference electrode is 1-10 um, for example, 3 um.

[0052] In some examples, since the influence on the driving voltage is not obvious when the distance between the signal electrode and the second reference electrode is within 20 um, the distance between the signal electrode and the second reference electrode can be set to be greater than 20 um.

[0053] In such Figure 4 The illustrated embodiment is described by taking the case where the number of the first sub-reference electrodes 21 is two as an example. In the actual use of the micromechanical switch, different numbers of first sub-reference electrodes can be arranged on the dielectric substrate according to the actual application scenario.

[0054] In one embodiment, the shape of the outline of the contact structure can be any one of an arc, a semicircle, a bar, a square, etc., but is not limited thereto. Figure 4 In the embodiment shown, the outline shape of the contact structure is a strip shape. In one embodiment, the number of contact structures provided on each first sub-reference electrode is at least one. Figure 4 In the illustrated embodiment, an example is given in which the number of contact structures 220 disposed on each first sub-reference electrode 21 is two.

[0055] In one example, the number of contact structures disposed on each first sub-reference electrode can be determined according to the percentage of the orthographic projection area of ​​the contact structure on the dielectric substrate to the orthographic projection area of ​​the notch on the dielectric substrate.

[0056] Optionally, in order to reduce the driving voltage of the micromechanical switch during operation and improve the stability of the operation of the micromechanical switch, the percentage of the orthographic projection area of ​​the contact structure on the dielectric substrate to the orthographic projection area of ​​the notch on the dielectric substrate may be 10% to 50%.

[0057] Preferably, the percentage of the orthographic projection area of ​​the contact structure on the dielectric substrate to the orthographic projection area of ​​the notch on the dielectric substrate can be 20% to 30%. Under this percentage, the driving voltage of the micromechanical switch can be reduced during operation, and the firmness of the contact structure and the bridge structure can be ensured, thereby ensuring the stability of the micromechanical switch when operating in a complex environment.

[0058] In some embodiments, reference Figure 1 and Figure 3 The membrane bridge 50 includes a bridge deck structure 51 and a support arm 52. The support arm 52 is located on the side of the second reference electrode 30 away from the dielectric substrate 10 and is directly connected to the second reference electrode 30. The membrane bridge enhances the stability of the bridge deck structure through the support arm.

[0059] In some embodiments, reference Figure 1 The bridge deck structure 51 has a hollow pattern 510 , and the hollow pattern 510 has no overlap with the orthographic projection of the first sub-reference electrode 21 on the dielectric substrate 10 .

[0060] By providing a hollow pattern on the membrane bridge deck structure, the overlapping area between the membrane bridge deck structure and the signal electrode is increased, further reducing the driving voltage of the micromechanical switch during operation.

[0061] In some embodiments, Figure 5 As shown, the bridge deck structure 51 includes a first portion 520 and a second portion 530 connected to each other, and the second portion 530 is connected to the support arm 52 of the membrane bridge 50 .

[0062] The orthographic projection of the first part of the bridge deck structure on the dielectric substrate covers the orthographic projection of the signal electrode on the dielectric substrate, and the orthographic projection of the second part of the bridge deck structure and the signal electrode on the dielectric substrate do not overlap.

[0063] In some examples, in order to increase the overlapping area between the membrane bridge deck structure and the signal electrode and further reduce the driving voltage of the micromechanical switch during operation, the width of the second part 530 of the bridge deck structure in the extension direction can be made smaller than the width of the first part 520 of the bridge deck structure in the extension direction of the second reference electrode.

[0064] In some examples, in order to further increase the overlapping area between the membrane bridge deck structure and the signal electrode and reduce the driving voltage, a hollow pattern may be provided in the first portion and / or the second portion. Figure 5 In the illustrated embodiment, the first portion and the second portion of the bridge deck structure are both provided with hollow patterns for illustration.

[0065] In some examples, providing a hollow pattern on the bridge deck structure of the membrane bridge helps to release the sacrificial layer when making a micromechanical switch.

[0066] In some embodiments, Figure 2 As shown, an interlayer insulating layer 60 is disposed on the side of the signal electrode 40 away from the dielectric substrate 10, and the first reference electrode 20 and the second reference electrode 30 are disposed on the side of the interlayer insulating layer 60 away from the dielectric substrate. The insulation strength between the signal electrode and the first reference electrode and the second reference electrode can be improved by adding an insulating layer.

[0067] In some embodiments, Figure 2 As shown, in order to further enhance the durability of the micromechanical switch, a first contact structure 70 can be provided on the side of the first reference electrode 20 close to the membrane bridge 50, and a second contact structure 80 can be provided on the side of the bridge structure 51 of the membrane bridge 50 close to the first reference electrode 20, and the first contact structure 70 and the second contact structure 80 are provided correspondingly. The first contact structure 70 and the second contact structure 80 improve the stability of the contact between the first reference electrode 20 and the bridge structure 51.

[0068] In some examples, the thickness of the first contact structure 70 and the second contact structure 80 may be 0.1-2 um, preferably 0.1-0.3 um.

[0069] In some examples, the pattern of the mask used to make the first contact structure 70 can be consistent with the pattern of the mask used to make the first reference electrode 20, and the pattern of the mask used to make the second contact structure 80 can be consistent with the pattern of the mask used to make the bridge deck structure 51. Thus, the number of masks used in making micromechanical switches can be saved.

[0070] In some embodiments, Figure 2 As shown, the second reference electrode 30 includes: a second sub-reference electrode 31 and a third sub-reference electrode 32 which are stacked, and the third sub-reference electrode 31 is located on the side of the second sub-reference electrode 30 away from the dielectric substrate 10; the support arm 52 of the membrane bridge 50 is located on the side of the third sub-reference electrode 30 away from the dielectric substrate 10. The height of the second sub-reference electrode 31 away from the dielectric substrate 10 is consistent with the height of the first reference electrode 20 away from the dielectric substrate 10. This improves the flatness of the bridge deck structure and enhances the stability of the bridge deck structure.

[0071] In some examples, in order to facilitate processing and improve the flatness of the bridge deck structure of the membrane bridge, the third sub-reference electrode and the membrane bridge can be processed into an integrated structure, and the second sub-reference electrode and the first reference electrode can be placed in one layer for processing.

[0072] In some examples, a third contact structure may be provided at a layer of the second sub-reference electrode away from the dielectric substrate, the shape of the third contact structure corresponding to the second sub-reference electrode, and the thickness in a direction away from the dielectric substrate is the same as that of the first contact structure.

[0073] In some embodiments, the dielectric substrate may be a glass substrate, a flexible substrate or a printed circuit board. The signal electrode, the first reference electrode, the second reference electrode and the membrane bridge may be made of metals with good electrical conductivity, such as copper, aluminum, molybdenum, titanium, silver, gold, nickel, tungsten and the like, or alloys of several metals, and may also be composed of stacked layers of different metals. Figure 6 A schematic diagram of the structure of a micromechanical switch.

[0074] Figure 7 It is a schematic diagram of the structure of a micromechanical switch whose membrane bridge is not shown. Figure 8 for Figure 6 A cross-sectional view of a micromechanical switch, specifically, Figure 8 The cross-sectional view is Figure 6 Cross-sectional view of the micromechanical switch along the C-C' direction.

[0075] In some embodiments, reference Figure 6 to Figure 8The micromechanical switch specifically includes: a dielectric substrate 10, a first reference electrode 20, a second reference electrode 30, a signal electrode 40 and a membrane bridge 50; the first reference electrode 20 and the second reference electrode 30 are arranged on the dielectric substrate 10, and the first reference electrode 20 includes a plurality of first sub-reference electrodes 21 that are disconnected and arranged along its extension direction; the signal electrode 40 is arranged on the dielectric substrate 10, and at least part of the signal electrode 40 is located between the orthographic projections of the first reference electrode 20 and the second reference electrode 30 on the dielectric substrate 10; the membrane bridge 50 is arranged on the signal electrode The layer where the first reference electrode 40, the first reference electrode 20 and the second reference electrode 30 are located is on the side away from the dielectric substrate, and there is a certain distance between the bridge surface structure 51 of the membrane bridge 50 and the signal electrode 40, and the orthographic projections of the two on the dielectric substrate 10 at least partially overlap; the first sub-reference electrode 21 includes a main structure 210, and a contact structure 220 connected to the main structure 210, and the orthographic projections of the bridge surface structure 51 of the membrane bridge 50 and the contact structure 220 on the dielectric substrate 10 at least partially overlap, and the orthographic projections of the bridge surface structure 51 of the membrane bridge 50 and the main structure 210 on the dielectric substrate 10 do not overlap. For any adjacent first sub-reference electrodes 21, the contact structure 220 is located between the areas defined by the two main structures 210; the signal electrode 40 has a groove 410 at a position corresponding to the contact structure 220, and the orthographic projection of one contact structure 220 on the dielectric substrate 10 is located within the orthographic projection of one groove 410 on the dielectric substrate 10.

[0076] In the disclosed embodiment, when the micromechanical switch is working, by applying driving voltages of different magnitudes to the second reference electrode and the signal electrode respectively, the membrane bridge directly in contact with the second reference electrode has a driving voltage close to that of the second reference electrode, thereby generating an electrostatic force between the signal electrode and the bridge surface structure of the membrane bridge. Under the action of the electrostatic force, the bridge surface structure moves toward the direction of the signal electrode until it contacts the contact structure of the multiple first sub-reference electrodes in the first reference electrode, thereby achieving conduction of the multiple first sub-reference electrodes.

[0077] The disclosed embodiment reduces the contact area between the membrane bridge and the first sub-reference electrode by making the bridge deck structure of the membrane bridge contact with the contact structure of the first sub-reference electrode, thereby helping to solve the problem of collapse of the bridge deck structure of the membrane bridge caused by the large contact area between the membrane bridge and the first sub-reference electrode, effectively weakening the deformation of the bridge deck structure of the membrane bridge and improving the stability of the operation of the micromechanical switch.

[0078] In some examples, such as Figures 9A to 9D The figure shows the structure of the signal electrode of the micromechanical switch. Figures 9A to 9DIn the embodiment, between any adjacent first sub-reference electrodes 21, the contact structure 220 is an area defined by the main structure 210 of two adjacent first sub-reference electrodes 21, and the position, shape and size of the groove 410 of the signal electrode 40 corresponds to the position, shape and size of the contact structure 220 of the adjacent first sub-reference electrode.

[0079] In some examples, the shape of the signal electrode may be adjusted without affecting the driving electrode, provided that the groove 410 of the signal electrode 40 corresponds to the contact structure 220 of the first sub-reference electrode adjacent to the signal electrode 40 . Fig. 9A The shape of the signal electrode is described by taking the example that the number of the contact structures of the first sub-reference electrode is 2. Figures 9B to 9D The shape of the signal electrode is described by taking the case where the number of the contact structure of the first sub-reference electrode is 1 as an example.

[0080] It should be understood that the embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0081] In some embodiments, Fig. 10A As shown, the bridge deck structure 51 includes a first portion 520 and a second portion 530 which are relatively connected, and the second portion 530 is connected to the support arm 52 of the membrane bridge 50; the orthographic projection of the first portion 520 on the dielectric substrate 10 covers the orthographic projection of the signal electrode 40 on the dielectric substrate 10, and the orthographic projection of the second portion 530 and the signal electrode 40 on the dielectric substrate 10 do not overlap. In order to further reduce the driving voltage when the micromechanical switch is working and increase the overlapping area between the membrane bridge deck structure and the signal electrode, the width of the second portion 530 in the extension direction of the second reference electrode can be made smaller than the width of the first portion 520 in the extension direction of the second reference electrode.

[0082] In some examples, in order to further reduce the driving voltage, a hollow pattern may be provided in the first portion and / or the second portion. Fig. 10A In the illustrated embodiment, description is made by taking an example that both the first part and the second part of the bridge deck structure have the hollow pattern 510 .

[0083] In some examples, such as Fig. 10B and 10C As shown, the shape of the hollow pattern and its position on the bridge deck structure can be varied.

[0084] It should be understood that the embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0085] In some embodiments, Figure 8As shown, an interlayer insulating layer 60 is disposed on the side of the signal electrode 40 away from the dielectric substrate 10, and the first reference electrode 20 and the second reference electrode 30 are disposed on the side of the interlayer insulating layer 60 away from the dielectric substrate. The insulation strength between the signal electrode and the first reference electrode and the second reference electrode can be improved by adding an insulating layer.

[0086] In some embodiments, Figure 8 As shown, a first contact structure 70 is provided on a side of the first reference electrode 20 close to the membrane bridge 50, and a second contact structure 80 is provided on a side of the bridge surface structure 51 of the membrane bridge 50 close to the first reference electrode 20, and the first contact structure 70 and the second contact structure 80 are provided correspondingly. The first contact structure 70 and the second contact structure 80 improve the stability of the contact between the first reference electrode 20 and the bridge surface structure 51.

[0087] The present invention also provides a method for manufacturing a micromechanical switch, the method specifically comprising the following steps:

[0088] S1. Select a dielectric substrate. The dielectric substrate may be a glass substrate, a flexible substrate or a printed circuit board. This embodiment takes a glass substrate as an example.

[0089] S2, a signal electrode layer is manufactured on a glass substrate by magnetron sputtering, or a combination of magnetron sputtering and electroplating, and the signal electrode is patterned on the signal electrode layer by processes such as coating photoresist, exposing, developing, and etching to manufacture a Figure 7 and Figure 8 The signal electrode is shown.

[0090] The signal electrode can be made of metals with good electrical conductivity, such as copper, aluminum, molybdenum, titanium, silver, gold, nickel, tungsten, etc., or alloys composed of several metals. The signal electrode can also be a stacked combination of different metals.

[0091] The thickness of the signal electrode may be between 0.2-5 um, preferably between 0.3-2 um.

[0092] S3, forming an insulating layer on the side of the signal electrode layer away from the glass substrate, coating photoresist on the side of the insulating layer away from the glass substrate, exposing and developing, and etching away the insulating layer in the lower electrode lead area by dry etching.

[0093] The insulating layer may be made of inorganic materials, such as silicon nitride, silicon oxynitride, silicon oxide, or may be made of organic photoresist, or may be a stack of inorganic materials and organic photoresist.

[0094] In order to achieve a good insulation effect, the thickness of the insulation layer is controlled within the range of 0.1 to 1 um, preferably 0.3 to 0.5 um.

[0095] S4, depositing a first reference electrode layer on the side of the insulating layer away from the glass substrate by magnetron sputtering or electroplating, and patterning the reference electrode layer by a metal lift-off process to form a Figure 7 and Figure 8 The first reference electrode and the second sub-reference electrode are shown.

[0096] The thickness of the first reference electrode and the second sub-reference electrode in the direction away from the glass substrate can be controlled in the range of 0.2-5 um, preferably 0.3-2 um.

[0097] The material of the first reference electrode and the second sub-reference electrode can be selected from metals, such as copper, aluminum, molybdenum, titanium, silver, gold, nickel, tungsten, etc., or alloys composed of several metals. The first reference electrode and the second sub-reference electrode can also be a stacked combination of different metals.

[0098] S5. Making a sacrificial layer on the side of the reference electrode layer facing away from the glass substrate.

[0099] The sacrificial layer may be made of organic material or inorganic material, and the sacrificial layer can keep the glass substrate flat.

[0100] S6, depositing a second reference electrode layer on the side of the first reference electrode layer away from the glass substrate by magnetron sputtering, or a combination of magnetron sputtering and electroplating, and then patterning by coating photoresist, exposing, developing, and etching to form a second reference electrode layer. Figure 6 and Figure 8 The third sub-reference electrode and membrane bridge are shown.

[0101] The materials of the third sub-reference electrode and the membrane bridge can be selected from metals such as copper, aluminum, molybdenum, titanium, silver, gold, nickel, tungsten, or alloys of several metals. The second reference electrode layer can also be a stacked combination of different metals.

[0102] The thickness of the third sub-reference electrode and the membrane bridge in the direction away from the glass substrate can be controlled within the range of 0.1 to 10 um, preferably within the range of 0.5 to 5 um.

[0103] S7. Finally, the sacrificial layer is released through a wet etching process or a dry etching process, thereby completing the production of the entire micromechanical switch.

[0104] Based on the same inventive concept, a second aspect of an embodiment of the present invention provides an antenna, comprising: the micromechanical switch as described above.

[0105] The antenna may include multiple micromechanical switches. By applying a driving voltage to the micromechanical switches, multiple first sub-reference electrodes separated in the micromechanical switches are turned on. By adjusting the number of the turned-on first sub-reference electrodes, a frequency-reconfigurable antenna can be realized.

[0106] The antenna can meet the requirements of communications in different frequency bands and can be applied to different smart terminals according to needs.

[0107] A person skilled in the art should understand that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope of the disclosure of the embodiments of the present invention (including the claims) is limited to these examples; under the concept of the embodiments of the present invention, the technical features in the above embodiments or different embodiments can also be combined, and there are many other changes in different aspects of the embodiments of the present invention as above, which are not provided in detail for the sake of simplicity. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present invention should be included in the protection scope of the embodiments of the present invention.

Claims

1. A micromechanical switch, characterized in that: include: dielectric substrate; A first reference electrode and a second reference electrode are arranged on the dielectric substrate, and the first reference electrode includes a plurality of first sub-reference electrodes that are arranged in a disconnected manner along an extending direction thereof; A signal electrode is disposed on the dielectric substrate, and an orthographic projection of at least a portion of the signal electrode on the dielectric substrate is located between the orthographic projections of the first reference electrode and the second reference electrode on the dielectric substrate; A membrane bridge is arranged on a side of the layer where the signal electrode, the first reference electrode and the second reference electrode are located away from the dielectric substrate, and there is a certain distance between the bridge surface structure of the membrane bridge and the signal electrode, and the orthographic projections of the two on the dielectric substrate at least partially overlap; wherein, The first sub-reference electrode includes a main structure and a contact structure connected to the main structure, and the bridge deck structure of the membrane bridge and the orthographic projection of the contact structure on the dielectric substrate at least partially overlap, and the bridge deck structure of the membrane bridge and the orthographic projection of the main structure on the dielectric substrate do not overlap.

2. The switch according to claim 1, characterized in that: The main structure has a notch facing the second reference electrode, and the contact structure is connected in the notch and extends toward the second reference electrode; The signal electrode has a plurality of grooves, and an orthographic projection of one of the contact structures on the dielectric substrate is located within an orthographic projection of one of the grooves on the dielectric substrate.

3. The switch according to claim 1, characterized in that: For any adjacent first sub-reference electrodes, the contact structure is located between the areas defined by the two main structures; The signal electrode has a plurality of grooves, and an orthographic projection of one of the contact structures on the dielectric substrate is located within an orthographic projection of one of the grooves on the dielectric substrate.

4. The switch according to claim 1, characterized in that: The first sub-reference electrode includes at least one of the contact structures.

5. The switch according to any one of claims 1, characterized in that: The bridge deck structure has a hollow pattern; the hollow pattern has no overlap with the orthographic projection of the first sub-reference electrode on the dielectric substrate.

6. The switch according to any one of claims 5, characterized in that: The hollowed-out image has no overlap with the orthographic projection of the signal electrode on the dielectric substrate.

7. The switch according to any one of claims 1 to 6, characterized in that: The bridge deck structure includes a first part and a second part that are relatively connected, and the second part is connected to the support arm of the membrane bridge; the orthographic projection of the first part on the dielectric substrate covers the orthographic projection of the signal electrode on the dielectric substrate, and the second part has no overlap with the orthographic projection of the signal electrode on the dielectric substrate; wherein the width of the second part along the extension direction of the second reference electrode is smaller than the width of the first part along the extension direction of the second reference electrode.

8. The switch according to any one of claims 1 to 6, characterized in that: The supporting arm of the membrane bridge is located on a side of the second reference electrode away from the dielectric substrate, and is directly connected to the second reference electrode.

9. The switch according to any one of claims 1 to 6, characterized in that: The second reference electrode comprises: a second sub-reference electrode and a third sub-reference electrode which are stacked, wherein the third sub-reference electrode is located on a side of the second sub-reference electrode away from the dielectric substrate; The supporting arm of the membrane bridge is located at a side of the third sub-reference electrode away from the dielectric substrate.

10. The switch according to any one of claims 1 to 6, characterized in that: An interlayer insulating layer is arranged on a side of the signal electrode away from the dielectric substrate, and the first reference electrode and the second reference electrode are arranged on a side of the interlayer insulating layer away from the dielectric substrate.

11. The switch according to any one of claims 1 to 6, characterized in that: A first contact structure is provided on a side of the first reference electrode close to the membrane bridge, and a second contact structure is provided on a side of the bridge surface structure close to the first reference electrode. The first contact structure and the second contact structure are provided correspondingly.

12. An antenna, characterized in that: include: A micromechanical switch as claimed in any one of claims 1 to 11.

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