An integrated magnetoelectric antenna

Abstract

The utility model provides a kind of integrated magnetoelectric antenna, with two or more resonance regions, comprising: substrate;Seed layer;Bottom electrode layer;Piezoelectric layer;Magnetostrictive layer, located part piezoelectric layer surface, including connecting part and two or more mutually spaced resonant parts, the resonant part is linear type arrangement or matrix type arrangement, each resonant part corresponds a resonance region.Two or more resonance regions are equivalent to increase electromagnetic radiation source in antenna unit, and antenna gain can be improved;At the same time, since input power is apportioned to multiple resonance regions, the power capacity of antenna is also improved.

Description

Technical Field

[0001] This utility model relates to the field of radio frequency antennas, specifically to an integrated magnetoelectric antenna. Background Technology

[0002] With the rapid development of mobile communication technology, the demand for antenna miniaturization and integration is becoming increasingly prominent. Most current traditional antennas are based on the principle of electromagnetic wave resonance, and their size is limited by the free-space wavelength corresponding to the operating frequency. Ultra-miniature magnetoelectric antennas based on magnetoelectric heterostructures achieve efficient transmission and reception of electromagnetic waves by utilizing the positive and inverse magnetoelectric effects during acoustic wave resonance, thus potentially reducing the size of traditional antennas by orders of magnitude. Therefore, fabricating integrated magnetoelectric antennas with good compatibility with current processes and high gain and power capacity is a technical problem that needs to be solved. Utility Model Content

[0003] The technical problem solved by this invention is to provide an integrated magnetoelectric antenna that, while maintaining good compatibility with existing processes, can improve antenna gain and power capacity.

[0004] To solve the above-mentioned technical problems, the present invention provides an integrated magnetoelectric antenna, comprising: a substrate having an opening therein; a seed layer located on the surface of the substrate and on the opening to enclose the opening and form a cavity; a bottom electrode layer located on the surface of the seed layer; a piezoelectric layer located on the surface of the bottom electrode layer; a magnetostrictive layer located on a portion of the surface of the piezoelectric layer, the magnetostrictive layer including a connecting portion and two or more resonant portions spaced apart from each other, the projection of the connecting portion on the surface of the substrate being located outside the cavity, the projection of the resonant portion on the surface of the substrate being located inside the cavity, each resonant portion being connected to the connecting portion, each resonant portion corresponding to a resonant region located between the upper surface of the resonant portion and the bottom of the cavity; and a top electrode layer located on the surface of the connecting portion.

[0005] Optionally, the two or more resonant sections are arranged in a linear or matrix configuration.

[0006] Optionally, two or more resonant sections are arranged in a linear pattern, and the number of cavities is one, with the projections of all the resonant sections onto the substrate surface located within the cavity.

[0007] Optionally, the projection of the linearly arranged resonant portion onto the substrate surface is a superior arc shape, the radius of which ranges from 80μm to 150μm, and the projection of the chord of the superior arc shape onto the substrate surface coincides with the partial projection of one side of the cavity onto the substrate surface.

[0008] Optionally, the minimum distance between the linearly arranged resonant sections is 80μm~130μm.

[0009] Optionally, two or more resonant sections are arranged in a matrix, and the number of cavities is the same as the number of resonant sections and corresponds one-to-one, with the projection of each resonant section on the substrate surface located in the corresponding cavity.

[0010] Optionally, the projection of the matrix-arranged resonant portion onto the substrate surface is a superior arc shape, the radius of which ranges from 80μm to 140μm, and the projection of the chord of the superior arc shape onto the substrate surface coincides with the partial projection of one side of the corresponding cavity onto the substrate surface.

[0011] Optionally, the projected length of the arc-shaped chord on the substrate surface ranges from 85 μm to 115 μm.

[0012] Optionally, the integrated magnetoelectric antenna further includes: a through-hole penetrating the piezoelectric layer, the bottom electrode layer, and the seed layer, the through-hole communicating with the cavity, the cavity being formed using a sacrificial layer process.

[0013] Optionally, the material of the bottom electrode layer includes at least one of aluminum, titanium, molybdenum, tungsten, copper, silver, platinum, and gold; the material of the piezoelectric layer includes at least one of quartz, aluminum nitride, scandium aluminum nitride, gallium nitride, zinc oxide, lithium niobate, lithium tantalate, and lead zirconate titanate; the material of the magnetostrictive layer includes at least one of nickel, iron-gallium alloy, iron-gallium / iron-cobalt heterojunction, iron-gallium-boron alloy, iron-cobalt-silicon-boron alloy, and iron-silicon-boron-carbon alloy; and the material of the top electrode layer includes at least one of aluminum, titanium, copper, silver, platinum, and gold.

[0014] Compared with the prior art, the technical solution of this utility model has the following beneficial effects: The integrated magnetoelectric antenna provided by this invention features two or more spaced-apart resonant sections in a magnetostrictive layer. These spaced-apart resonant sections can be matched with corresponding anchor support structures, thereby achieving efficient impedance matching. Due to the design of two or more spaced-apart resonant sections, and the fact that the projection of each resonant section onto the substrate surface is located within a cavity, two or more resonant regions are formed between the upper surface of the resonant section and the bottom of the cavity. These two or more resonant regions are equivalent to adding electromagnetic radiation sources to the antenna element, which can improve the antenna gain. Simultaneously, the two or more resonant regions distribute the input power among the various resonant regions, further enhancing the power capacity. Furthermore, because the resonant sections are spaced apart, the problem of thin-film collapse caused by an excessively large single resonant region is overcome, enhancing the mechanical robustness of the antenna.

[0015] Furthermore, the cavity structure is formed using a sacrificial layer process, eliminating the need for substrate thinning or etching, thus exhibiting good compatibility with existing processes and facilitating mass production. Simultaneously, since substrate thickness is related to resonant frequency and input impedance, the cavity formation allows for better impedance matching of the magnetoelectric antenna within the specified operating frequency band. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the integrated magnetoelectric antenna according to an embodiment of the present invention; Figure 2 This is a top view of the integrated magnetoelectric antenna of Embodiment 1 of this utility model; Figure 3 This is a top view of the integrated magnetoelectric antenna of Embodiment 2 of this utility model; Figure 4 This is a top view of the integrated magnetoelectric antenna of Embodiment 3 of this utility model; Figure 5 This is a top view of the integrated magnetoelectric antenna of Embodiment 4 of this utility model; Figure 6 Impedance matching diagrams for the integrated magnetoelectric antenna and the single-resonant region magnetoelectric antenna according to embodiments of this utility model; Figure 7 The diagram shows the actual gain improvement of the integrated magnetoelectric antenna and the single-resonant region magnetoelectric antenna according to embodiments of this utility model.

[0017] Explanation of reference numerals in the attached figures: 100 - Substrate; 120 - Cavity; 130 - Through-hole; 200 - Seed layer; 300 - Bottom electrode layer; 400 - Piezoelectric layer; 500 - Magnetostrictive layer; 510, 520, 530, 540 - Resonant section; 511, 521, 531, 541 - Curved string; 512 - Connector; 600-Top electrode layer; The length of the L1-1×2 type cavity; the width of the W1-1×2 type cavity; the minimum distance between the gap1-1×2 type resonators; the length of the L2-1×3 type cavity; the width of the W2-1×3 type cavity; the minimum distance between the gap2-1×3 type resonators; the length of the L3-1×4 type cavity; the width of the W3-1×4 type cavity; the minimum distance between the gap3-1×4 type resonators; the length of the L4-2×2 type cavity; the width of the W4-2×2 type cavity; the minimum distance between the gap4-2×2 type resonators; the distance between the gap5-2×2 type resonators. Detailed Implementation

[0018] As described in the background section, the development of integrated magnetoelectric antennas with good compatibility with existing processes and high gain and power capacity is a technical problem that needs to be solved. This will be explained in detail below.

[0019] Magnetoelectric antennas with a single resonant region suffer from low gain, short communication distance, and poor signal quality, limiting their application scenarios. To address the low gain issue, one approach involves coupling multiple high-order harmonic bulk acoustic waves to co-excite the magnetoelectric antenna and generate broadband radiation. While this method is simple to fabricate and offers high power capacity, the resonant frequency and input impedance are strongly correlated with the substrate thickness, making impedance matching difficult to achieve within a specified operating frequency band. Another approach uses back-etched thin films to achieve broadband resonant coupling through thickness design, but this results in low power capacity and mechanical robustness, as well as poor process consistency, making it difficult to meet the demands of mass production.

[0020] To solve the above-mentioned technical problems, the present invention provides an integrated magnetoelectric antenna, which increases the electromagnetic radiation source by setting two or more resonant regions, thereby improving the antenna gain and power capacity.

[0021] To make the above-mentioned objectives, features, and beneficial effects of this utility model more apparent and understandable, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0022] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification, claims, and drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a particular order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the utility model described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus. Additionally, directional terms such as above, below, up, down, upward, downward, left, right, etc., are used relative to exemplary embodiments as they are shown in the figures, with upward or upper directions pointing towards the top of the corresponding figure and downward or lower directions pointing towards the bottom of the corresponding figure.

[0023] Figure 1This is a schematic diagram of the structure of the integrated magnetoelectric antenna according to an embodiment of the present invention.

[0024] Figure 2 This is a top view of the integrated magnetoelectric antenna of Embodiment 1 of this utility model.

[0025] in, Figure 1 yes Figure 2 A schematic diagram of the cross-sectional structure along the Y direction at section line Z. Figure 2 yes Figure 1 A top view along the X direction.

[0026] Please refer to Figure 1 and Figure 2 The integrated magnetoelectric antenna includes: a substrate 100 and a seed layer 200, a bottom electrode layer 300, a piezoelectric layer 400, a magnetostrictive layer 500 and a top electrode layer 600 stacked sequentially from bottom to top on the surface of the substrate 100.

[0027] The material of substrate 100 may include at least one of high-resistivity silicon, gallium arsenide, indium phosphide, and sapphire. Preferably, the material of substrate 100 may be high-resistivity silicon (100).

[0028] An opening is provided in the substrate 100.

[0029] The seed layer 200 is located on the surface of the substrate 100 and on the opening to enclose the opening and form a cavity 120.

[0030] Specifically, the seed layer 200 can be made of aluminum nitride with a thickness of 35 nm.

[0031] The cavity 120 is formed using a sacrificial layer process, thus eliminating the need for thinning and etching of the substrate 100, ensuring good compatibility with existing processes and facilitating mass production. Simultaneously, since the thickness of the substrate 100 is related to the resonant frequency and input impedance, the formation of the cavity 120 enables the magnetoelectric antenna to achieve better impedance matching within the specified operating frequency band.

[0032] Furthermore, the integrated magnetoelectric antenna also includes: through-hole 130.

[0033] Through-hole 130 is used to form cavity 120 through sacrificial layer process.

[0034] Specifically, the through hole 130 penetrates the seed layer 200, the bottom electrode layer 300, and the piezoelectric layer 400 to connect the cavity 120.

[0035] Specifically, the bottom electrode layer 300 is located on the surface of the seed layer 200.

[0036] The material of the bottom electrode layer 300 may include at least one of aluminum, titanium, molybdenum, tungsten, copper, silver, platinum and gold.

[0037] Preferably, the bottom electrode layer 300 can be made of molybdenum.

[0038] Preferably, the thickness of the bottom electrode layer 300 is 110 nm.

[0039] The piezoelectric layer 400 is located on the surface of the bottom electrode layer 300.

[0040] The material of the piezoelectric layer 400 may include at least one of quartz, aluminum nitride, scandium aluminum nitride, gallium nitride, zinc oxide, lithium niobate, lithium tantalate, and lead zirconate titanate.

[0041] Aluminum nitride is preferred, with a layer thickness of 35 nm.

[0042] The magnetostrictive layer 500 is located on the surface of part of the piezoelectric layer 400.

[0043] The magnetostrictive layer 500 is made of at least one of nickel, iron gallium alloy, iron gallium / iron cobalt heterojunction, iron gallium boron alloy, iron cobalt silicon boron alloy and iron silicon boron carbon alloy, preferably iron gallium alloy, and has a layer thickness of 510 nm.

[0044] Specifically, the magnetostrictive layer 500 includes a connecting portion 512 and resonant portions 510 spaced apart from each other.

[0045] The number of resonant parts can be two or more, and the two or more resonant parts can be arranged in a linear or matrix manner.

[0046] The top electrode layer 600 is located on the surface of part of the magnetostrictive layer 500.

[0047] Furthermore, the top electrode layer 600 is located on the surface of the connection portion 512.

[0048] The material of the top electrode layer 600 includes at least one of aluminum, titanium, copper, silver, platinum and gold, preferably titanium and gold, with thicknesses of 30 nm and 250 nm, respectively.

[0049] Example 1 In this embodiment, there are two resonant sections 510, and the two resonant sections 510 are arranged in a straight line, which is simply referred to as the 1×2 type.

[0050] In this embodiment, the projection of the resonant part 510 onto the surface of the substrate 100 is a superior arc shape. The superior arc shape design can avoid the coupling between the transverse resonance and the longitudinal bulk acoustic wave resonance, thereby improving the antenna gain.

[0051] The projection of the arc-shaped chord 511 onto the surface of the substrate 100 is a straight line. The projection of the arc-shaped chord 511 onto the surface of the substrate 100 coincides with the partial projection of one side of the cavity 120 onto the surface of the substrate 100.

[0052] Specifically, the projection of the connecting portion 512 on the substrate surface is located outside the cavity 120, the projection of the resonant portion 510 on the substrate surface is located inside the cavity 120, and each resonant portion 510 is connected to the connecting portion 512.

[0053] Each resonant part 510 corresponds to a resonant region, which avoids the thin film from collapsing due to the excessive size of a single resonant part and enhances mechanical strength. The resonant region is located between the upper surface of the resonant part 510 and the bottom of the cavity 120.

[0054] Specifically, the radius of the arc-shaped 1×2 resonator 510 is 101 μm, the projected length of the chord 511 of the arc-shaped 1×2 resonator 510 on the surface of the substrate 100 is 100 μm, and the minimum distance gap1 between the 1×2 resonators 510 is 100 μm. The length L1 of the 1×2 cavity 120 is 580 μm, and the width W1 of the 1×2 cavity 120 is 227 μm. The area of ​​the cavity 120 is slightly larger than the total area of ​​the resonator 510, and part of the lower boundary of the cavity 120 overlaps with the projection of the chord 511 of the arc-shaped 1×2 resonator on the surface of the substrate 100. Due to the structural relationship of the device, the projected length of the chord 511 of the arc-shaped 1×2 resonator on the surface of the substrate 100 is consistent with the anchor width, and the 100 μm anchor width allows for better adjustment of the antenna impedance matching.

[0055] In the integrated magnetoelectric antenna of this embodiment, two or more mutually spaced resonant sections 510 are provided in the magnetostrictive layer. These mutually spaced resonant sections 510 can be matched with corresponding anchor support structures, thereby achieving efficient impedance matching. Due to the design of two or more mutually spaced resonant sections 510, and the projection of each resonant section 510 onto the surface of the substrate 100 located within the cavity 120, two or more resonant regions are formed between the upper surface of the resonant section 510 and the bottom of the cavity 120. These two or more resonant regions are equivalent to adding electromagnetic radiation sources to the antenna element, which can improve the antenna gain. Simultaneously, the two or more resonant regions distribute the input power among the various resonant regions, further enhancing the power capacity. Furthermore, since the resonant sections 510 are mutually spaced, the problem of thin film collapse caused by an excessively large single resonant region is overcome, enhancing the mechanical robustness of the antenna.

[0056] Example 2 In this embodiment, please refer to Figure 3 There are three resonant sections 520, and the three resonant sections 520 are arranged in a straight line, which can be simply referred to as the 1×3 type.

[0057] The radius of the superior arc shape of the resonant part 520 ranges from 80μm to 150μm, the minimum distance between the resonant parts 520 is from 80μm to 130μm, and the projection length of the chord 521 of the superior arc shape on the surface of the substrate 100 ranges from 85μm to 115μm. The distance between adjacent resonant parts 520 is relatively close. To facilitate the etching of the sacrificial layer, there is only one cavity 120, and the projections of all the resonant parts 520 on the surface of the substrate 100 are located within the cavity 120.

[0058] Specifically, the radius of the arc-shaped 1×3 resonator 520 is 101 μm, and the projected length of the chord 521 of the arc-shaped 1×3 resonator on the surface of the substrate 100 is 90 μm. The 90 μm anchor width allows for better adjustment of the antenna's impedance matching. The minimum distance gap2 between the 1×3 resonators 520 is 100 μm. The length L2 of the 1×3 cavity 120 is 870 μm, and the width W2 of the 1×3 cavity 120 is 227 μm.

[0059] Example 3 In this embodiment, please refer to Figure 4 The resonant section 530 is arranged in a straight line and there are 4 of them, which can be simply referred to as the 1×4 type.

[0060] Specifically, the radius of the arc-shaped 1×4 resonator 530 is 101 μm, and the projected length of the chord 531 of the arc-shaped 1×4 resonator on the surface of the substrate 100 is 110 μm. The 110 μm anchor width allows for better adjustment of the antenna's impedance matching. The minimum distance gap3 between the 1×4 resonators 530 is 100 μm. The length L3 of the 1×4 cavity 120 is 1170 μm, and the width W3 of the 1×4 cavity 120 is 217 μm.

[0061] Example 4 In this embodiment, please refer to Figure 5 The resonant section 540 is arranged in a matrix and there are 4 of them, which can be simply referred to as the 2×2 type.

[0062] The radius of the superior arc shape of the resonant section 540 ranges from 80 μm to 140 μm, and the projection length of the chord 541 of the superior arc shape on the surface of the substrate 100 ranges from 85 μm to 115 μm. The number of cavities 120 is the same as the number of resonant sections 540, and the projection of each resonant section 540 on the surface of the substrate 100 is located within a cavity 120.

[0063] Specifically, the radius of the arc-shaped 2×2 resonator 540 is 101 μm, the projected length of the chord 541 of the arc-shaped 2×2 resonator 540 on the surface of the substrate 100 is 100 μm, the minimum distance gap4 between the 2×2 resonators 540 is 186.5 μm, the distance gap5 between the 2×2 resonators 540 is 320 μm, the length L4 of the 2×2 cavity 120 is 280 μm, the width W4 of the 2×2 cavity 120 is 228 μm, the area of ​​the cavity 120 is slightly larger than the area of ​​a single resonator 540, and the partial projection of any boundary of the cavity 120 on the surface of the substrate 100 overlaps with the projection of the chord 541 of the arc-shaped 2×2 resonator 540 on the surface of the substrate 100. Due to the structural relationship of the device, the projected length of the chord 541 of the arc-shaped 2×2 resonator 540 on the surface of the substrate 100 is consistent with the anchor point width, and the 100 μm anchor point width allows for better adjustment of the antenna impedance matching.

[0064] Please refer to Figure 6 In this invention, 1×1 represents the prior art, 1×2 represents Embodiment 1, 1×3 represents Embodiment 2, 1×4 represents Embodiment 3, and 2×2 represents Embodiment 4. Embodiments 1, 2, 3, and 4 all exhibit a reflection coefficient |S11| higher than -5dB at the resonant frequency within a specified frequency band (~2.35GHz), demonstrating good impedance matching compared to the prior art.

[0065] Please refer to Figure 7 In this invention, 1×1 represents the prior art, 1×2 represents Embodiment 1, 1×3 represents Embodiment 2, 1×4 represents Embodiment 3, and 2×2 represents Embodiment 4. Embodiments 1, 2, 3, and 4 of this invention further improve the antenna gain compared to the prior art magnetoelectric antenna. With the increase in the number of resonant regions, in Embodiment 3, when the four resonant sections are arranged in a linear fashion, the actual antenna gain can be increased by 7.6 dB.

[0066] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. An integrated magnetoelectric antenna, characterized in that, include: A substrate having an opening therein; A seed layer is located on the substrate surface and the opening to enclose the opening and form a cavity; The bottom electrode layer is located on the surface of the seed layer; A piezoelectric layer is located on the surface of the bottom electrode layer; A magnetostrictive layer is located on a portion of the surface of the piezoelectric layer. The magnetostrictive layer includes a connecting portion and two or more resonant portions spaced apart from each other. The projection of the connecting portion on the substrate surface is located outside the cavity, and the projection of the resonant portion on the substrate surface is located inside the cavity. Each resonant portion is connected to the connecting portion, and each resonant portion corresponds to a resonant region. The resonant region is located between the upper surface of the resonant portion and the bottom of the cavity. The top electrode layer is located on the surface of the connection portion.

2. The integrated magnetoelectric antenna as described in claim 1, characterized in that, The two or more resonant sections are arranged in a linear or matrix configuration.

3. The integrated magnetoelectric antenna as described in claim 2, characterized in that, Two or more resonant sections are arranged in a linear pattern, and the number of cavities is one, with the projections of all the resonant sections onto the substrate surface located within the cavity.

4. The integrated magnetoelectric antenna as described in claim 3, characterized in that, The projection of the linearly arranged resonant section onto the substrate surface is a superior arc shape, the radius of which ranges from 80μm to 150μm, and the projection of the chord of the superior arc shape onto the substrate surface coincides with the partial projection of one side of the cavity onto the substrate surface.

5. The integrated magnetoelectric antenna as described in claim 4, characterized in that, The minimum distance between the linearly arranged resonant sections is 80μm~130μm.

6. The integrated magnetoelectric antenna as described in claim 2, characterized in that, Two or more resonant sections are arranged in a matrix, and the number of cavities is the same as the number of resonant sections and corresponds one-to-one. The projection of each resonant section on the substrate surface is located in the corresponding cavity.

7. The integrated magnetoelectric antenna as described in claim 6, characterized in that, The projection of the matrix-arranged resonant part onto the substrate surface is a superior arc shape, the radius of which ranges from 80μm to 140μm, and the projection of the chord of the superior arc shape onto the substrate surface coincides with the partial projection of one side of the corresponding cavity onto the substrate surface.

8. The integrated magnetoelectric antenna as described in claim 4 or 7, characterized in that, The projected length of the arc-shaped chord on the substrate surface ranges from 85 μm to 115 μm.

9. The integrated magnetoelectric antenna as described in claim 1, characterized in that, Also includes: A through-hole is formed through the piezoelectric layer, the bottom electrode layer, and the seed layer, and the through-hole connects to the cavity, which is formed using a sacrificial layer process.

10. The integrated magnetoelectric antenna as described in claim 1, characterized in that, The material of the bottom electrode layer includes at least one of aluminum, titanium, molybdenum, tungsten, copper, silver, platinum and gold; The material of the piezoelectric layer includes at least one of quartz, aluminum nitride, scandium aluminum nitride, gallium nitride, zinc oxide, lithium niobate, lithium tantalate, and lead zirconate titanate; The magnetostrictive layer is made of at least one of nickel, iron-gallium alloy, iron-gallium / iron-cobalt heterojunction, iron-gallium-boron alloy, iron-cobalt-silicon-boron alloy, and iron-silicon-boron-carbon alloy. The material of the top electrode layer includes at least one of aluminum, titanium, copper, silver, platinum, and gold.

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