阅读说明：本技术 声波滤波器装置 (Acoustic wave filter device ) 是由 朴润锡 郑原圭 朴朶焌 丁大勳 孙尚郁 于 2019-06-20 设计创作，主要内容包括：本发明提供一种声波滤波器装置,所述声波滤波器装置包括谐振部、第一金属焊盘和第二金属焊盘。谐振部中的每个包括设置在基板上的下电极、设置在所述下电极的至少一部分上的压电层以及设置在所述压电层的至少一部分上的上电极。第一金属焊盘连接到所述谐振部中的相应的谐振部的所述上电极和所述下电极中的一个。第二金属焊盘设置在所述下电极、所述压电层和所述上电极重叠的有效区外部,并连接到所述谐振部中的相邻的谐振部的所述上电极和所述下电极中的另一个。设置在所述有效区外部的环形部仅设置在所述第一金属焊盘和所述第二金属焊盘中的任意一者的一部分上。(An acoustic wave filter device includes a resonance portion, a first metal pad, and a second metal pad. Each of the resonance sections includes a lower electrode provided on a substrate, a piezoelectric layer provided on at least a part of the lower electrode, and an upper electrode provided on at least a part of the piezoelectric layer. The first metal pad is connected to one of the upper electrode and the lower electrode of a corresponding one of the resonance sections. A second metal pad is disposed outside an effective area where the lower electrode, the piezoelectric layer, and the upper electrode overlap, and is connected to the other of the upper electrode and the lower electrode of an adjacent one of the resonance sections. The ring portion disposed outside the active area is disposed only on a portion of either one of the first and second metal pads.)

1. An acoustic wave filter device comprising:

resonance sections each including a lower electrode provided on a substrate, a piezoelectric layer provided on at least a part of the lower electrode, and an upper electrode provided on at least a part of the piezoelectric layer;

a first metal pad connected to one of the upper electrode and the lower electrode of a corresponding one of the resonance sections; and

a second metal pad disposed outside an effective area where the lower electrode, the piezoelectric layer, and the upper electrode overlap and connected to the other of the upper electrode and the lower electrode of an adjacent one of the resonance sections,

wherein the ring portion disposed outside the active area is disposed only on a portion of any one of the first and second metal pads.

2. The acoustic wave filter device according to claim 1, wherein the annular portion is provided so as to surround a part of the active area.

3. The acoustic wave filter device according to claim 1, wherein the first metal pad is connected to the lower electrode, the second metal pad is connected to the upper electrode, and

the ring portion is provided only in a part of the first metal pad.

4. The acoustic wave filter device according to claim 3, wherein the second metal pad connects the upper electrodes of the adjacent resonance sections.

5. The acoustic wave filter device according to claim 4, wherein an interval between adjacent resonance sections connected to the first metal pad having the ring portion is larger than an interval between adjacent resonance sections connected to the first metal pad not having the ring portion.

6. The acoustic wave filter device according to claim 4, wherein the second metal pad disposed opposite the first metal pad without the annular portion has a size in which an imaginary band shape extending from the annular portion is removed from the second metal pad disposed opposite the first metal pad with the annular portion.

7. The acoustic wave filter device according to claim 1, wherein the first metal pad and the second metal pad are formed using any one of gold (Au), gold-tin (Au-Sn) alloy, copper (Cu), copper-tin (Cu-Sn) alloy, aluminum (Al), and aluminum alloy.

8. The acoustic wave filter device according to claim 1, wherein the resonance portion further includes a film layer with a cavity formed between the film layer and the substrate.

9. The acoustic wave filter device according to claim 8, wherein the resonance portion further includes a passivation layer provided in a region other than a region where the first metal pad and the second metal pad are formed.

10. The acoustic wave filter device according to claim 8, wherein the resonance section further comprises an etching prevention section provided between the substrate and the lower electrode and around the cavity.

11. The acoustic wave filter device according to claim 10, wherein the resonance section further comprises an insertion layer provided at a position lower than a position of a part of the piezoelectric layer.

12. The acoustic wave filter device according to claim 1, wherein the upper electrode includes a frame portion provided at an edge of the active area, and

the ring portion is disposed outside the frame portion.

13. An acoustic wave filter device comprising:

resonance sections each including a lower electrode provided on a substrate, a piezoelectric layer provided on at least a part of the lower electrode, and an upper electrode provided on at least a part of the piezoelectric layer;

first metal pads, wherein, for each of the resonance sections, one of the upper electrode and the lower electrode is connected to a corresponding one of the first metal pads;

a second metal pad, wherein, for each of the resonance sections, the other of the upper electrode and the lower electrode is connected to a corresponding one of the second metal pads,

wherein an outer peripheral portion provided outside an effective area where the lower electrode, the piezoelectric layer, and the upper electrode overlap is provided only on a part of any one of the first metal pad and the second metal pad.

14. The acoustic wave filter device according to claim 13, wherein the peripheral portion is provided so as to surround a part of the active area.

15. The acoustic wave filter device according to claim 13, wherein the first metal pad is connected to the lower electrode, the second metal pad is connected to the upper electrode, and

the peripheral portion partially surrounds the first metal pad.

16. The acoustic wave filter device according to claim 15, wherein the second metal pad connects the upper electrodes of adjacent resonance sections.

17. The acoustic wave filter device according to claim 13, wherein the first metal pad and the second metal pad are formed using any one of gold (Au), gold-tin (Au-Sn) alloy, copper (Cu), copper-tin (Cu-Sn) alloy, aluminum (Al), and aluminum alloy.

18. The acoustic wave filter device according to claim 13, wherein the resonance portion further comprises a film layer with a cavity formed between the film layer and the substrate.

19. The acoustic wave filter device according to claim 18, wherein the resonance portion further includes a passivation layer provided in a region other than a region where the first metal pad and the second metal pad are formed.

Technical Field

The present disclosure relates to an acoustic wave filter device.

Background

As the market demand for available frequencies of mobile communication devices tends to saturate due to the explosive growth in the number of smart phone data users, additional frequencies are being secured through carrier aggregation, the use of high frequency bands, and the like. Therefore, the filter is still important in separating signals between different frequency bands. Furthermore, the filters themselves have become smaller and thinner to filter various frequency bands.

Disclosure of Invention

This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

In one general aspect, an acoustic wave filter device includes a resonance section, a first metal pad, and a second metal pad. Each of the resonance sections includes a lower electrode provided on a substrate, a piezoelectric layer provided on at least a part of the lower electrode, and an upper electrode provided on at least a part of the piezoelectric layer. The first metal pad is connected to one of the upper electrode and the lower electrode of a corresponding one of the resonance sections. A second metal pad is disposed outside an effective area where the lower electrode, the piezoelectric layer, and the upper electrode overlap, and is connected to the other of the upper electrode and the lower electrode of an adjacent one of the resonance sections. The ring portion disposed outside the active area is disposed only on a portion of either one of the first and second metal pads.

The ring portion may be disposed to surround a portion of the active area.

The first metal pad may be connected to the lower electrode, the second metal pad may be connected to the upper electrode, and the ring portion may be disposed only in a portion of the first metal pad.

The second metal pad may connect the upper electrodes of the adjacent resonance parts.

An interval between adjacent resonance parts connected to the first metal pad having the loop part may be greater than an interval between adjacent resonance parts connected to the first metal pad not having the loop part.

The second metal pad disposed opposite the first metal pad without the loop portion may have a size in which an imaginary band shape extending from the loop portion is removed from the second metal pad disposed opposite the first metal pad with the loop portion.

The first metal pad and the second metal pad may be formed using any one of gold (Au), gold-tin (Au-Sn) alloy, copper (Cu), copper-tin (Cu-Sn) alloy, aluminum (Al), and aluminum alloy.

The resonance part may further include a film layer with a cavity formed between the film layer and the substrate.

The resonance part may further include a passivation layer disposed in an area other than an area where the first and second metal pads are formed.

The resonance part may further include an etch prevention part disposed between the substrate and the lower electrode and around the cavity.

The resonance section may further include an insertion layer provided at a position lower than a position of a portion of the piezoelectric layer.

The upper electrode may include a frame portion disposed at an edge of the active region, and the ring portion may be disposed outside the frame portion.

In another general aspect, an acoustic wave filter device includes a resonance section, a first metal pad, and a second metal pad. Each of the resonance sections includes a lower electrode provided on a substrate, a piezoelectric layer provided on at least a part of the lower electrode, and an upper electrode provided on at least a part of the piezoelectric layer. For each of the resonance sections, one of the upper electrode and the lower electrode is connected to a corresponding one of the first metal pads. For each of the resonance sections, the other of the upper electrode and the lower electrode is connected to a corresponding one of the second metal pads. An annular portion provided outside an active area where the lower electrode, the piezoelectric layer, and the upper electrode overlap is provided only on a part of any one of the first metal pad and the second metal pad.

The ring portion may be disposed to surround a portion of the active area.

The first metal pad may be connected to the lower electrode, the second metal pad may be connected to the upper electrode, and the ring portion may be disposed only in a portion of the first metal pad.

The second metal pad may connect the upper electrodes of adjacent resonance parts.

The first metal pad and the second metal pad may be formed using any one of gold (Au), gold-tin (Au-Sn) alloy, copper (Cu), copper-tin (Cu-Sn) alloy, aluminum (Al), and aluminum alloy.

The resonance part may further include a film layer with a cavity formed between the film layer and the substrate.

The resonance part may further include a passivation layer disposed in an area other than an area where the first and second metal pads are formed.

Other features and aspects will be apparent from the following detailed description, the accompanying drawings, and the claims.

Drawings

Fig. 1 is a plan view showing an example of a part of an acoustic wave filter device.

Fig. 2 is a sectional view taken along line X-X' in fig. 1.

Fig. 3 is a plan view showing an example of a resonance part connected to a first metal pad having a ring part.

Fig. 4 is a plan view showing an example of the resonance portion connected to the first metal pad having no ring portion.

Fig. 5 is a graph illustrating a waveform of the resonance part shown in fig. 3 and a waveform of the resonance part shown in fig. 4.

Fig. 6 is a graph illustrating the performance of the resonance part shown in fig. 3 at the resonance point and the performance of the resonance part shown in fig. 4 at the resonance point.

Fig. 7 is a graph illustrating the performance of the resonance part shown in fig. 3 at an anti-resonance point and the performance of the resonance part shown in fig. 4 at the anti-resonance point.

Fig. 8 is a schematic sectional view showing an example of the resonance portion.

Detailed Description

The following detailed description is provided to assist the reader in obtaining a thorough understanding of the methods, devices, and/or systems described herein. However, various changes, modifications, and equivalents of the methods, apparatus, and/or systems described herein will be apparent to those skilled in the art after understanding the present disclosure. For example, the order of operations described herein is merely an example, which is not limited to the examples set forth herein, but rather, may be changed in addition to operations that must occur in a particular order, as will be apparent upon an understanding of the present disclosure. Moreover, descriptions of features known in the art may be omitted for the sake of clarity and conciseness.

The features described herein may be embodied in different forms and should not be construed as limited to the examples described herein. Rather, the examples described herein have been provided merely to illustrate some of the many possible ways to implement the methods, devices, and/or systems described herein that will be apparent after understanding the disclosure of the present application.

Throughout the specification, when an element (such as a layer, region, or substrate) is described as being "on," "connected to," or "coupled to" another element, the element may be directly "on," "connected to," or "coupled to" the other element, or one or more other elements may be present therebetween. In contrast, when an element is referred to as being "directly on," "directly connected to" or "directly coupled to" another element, there may be no intervening elements present.

As used herein, the term "and/or" includes any one of the associated listed items as well as any combination of any two or more of the items.

Although terms such as "first", "second", and "third" may be used herein to describe various elements, components, regions, layers or sections, these elements, components, regions, layers or sections are not limited by these terms. Rather, these terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section referred to in the examples described herein may be termed a second element, component, region, layer or section without departing from the teachings of the examples.

Spatially relative terms, such as "above … …," "upper," "below … …," and "lower," may be used herein for ease of description to describe one element's relationship to another element as illustrated in the figures. Such spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "above" or "upper" relative to another element would then be oriented "below" or "lower" relative to the other element. Thus, the term "above … …" includes both an orientation of "above … …" and "below … …" depending on the spatial orientation of the device. The device may also be otherwise oriented (e.g., rotated 90 degrees or at other orientations) and the spatially relative terms used herein should be interpreted accordingly.

The terminology used herein is for the purpose of describing various examples only and is not intended to be limiting of the disclosure. The singular is also intended to include the plural unless the context clearly dictates otherwise. The terms "comprises," "comprising," and "having" specify the presence of stated features, quantities, operations, elements, components, and/or combinations thereof, but do not preclude the presence or addition of one or more other features, quantities, operations, components, elements, and/or combinations thereof.

Variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, may be expected. Thus, the examples described herein are not limited to the particular shapes shown in the drawings, but include variations in shapes that occur during manufacture.

The features of the examples described herein may be combined in various ways that will be apparent after understanding the disclosure of the present application. Further, while the examples described herein have a variety of configurations, other configurations are possible as will be apparent upon understanding the disclosure of the present application.

Fig. 1 is a plan view showing an example of a part of an acoustic wave filter device, and fig. 2 is a sectional view taken along line X-X' in fig. 1.

Referring to fig. 1 and 2, the acoustic wave filter device 100 of the present application may include a substrate 120, a resonance part 200, a first metal pad 140, and a second metal pad 160.

The substrate 120 may be a silicon substrate. For example, as the substrate 120, a silicon wafer and/or a silicon-on-insulator (SOI) type substrate may be used.

The insulating layer 122 may be formed on the upper surface of the substrate 120, and may electrically isolate the substrate 120 from circuits formed at a position higher than the position of the substrate. The insulating layer 122 may also serve to prevent the substrate 120 from being etched by the etching gas when the cavity C is formed during the manufacturing process.

In the present example, the insulating layer 122 may utilize silicon dioxide (SiO) by at least one of a chemical vapor deposition process, a Radio Frequency (RF) magnetron sputtering process, and an evaporation process ₂) Silicon nitride (Si) ₃N ₄) Alumina (Al) ₂O ₃) And aluminum nitride (AlN)Any one or any combination of any two or more of them.

The resonance part 200 may be formed on the substrate 120. For example, the resonance part 200 may include a film layer 210, a lower electrode 220, a piezoelectric layer 230, an upper electrode 240, and a passivation layer 250.

The cavity C may be formed between the film layer 210 and the substrate 120. In addition, the film layer 210 may be formed using a material having low reactivity with an etching gas when removing a sacrificial layer (not shown). Containing silicon nitride (Si) ₃N ₄) Silicon dioxide (SiO) ₂) Magnesium oxide (MgO), zirconium oxide (ZrO) ₂) Aluminum nitride (AlN), lead zirconate titanate (PZT), gallium arsenide (GaAs), hafnium oxide (HfO) ₂) Alumina (Al) ₂O ₃) Titanium oxide (TiO) ₂) And a dielectric layer of any one of zinc oxide (ZnO) may be used as the film layer 210.

A seed layer (not shown) formed using aluminum nitride (AlN) may be formed on the film layer 210. For example, a seed layer may be disposed between the film layer 210 and the lower electrode 220. The seed layer may be formed using a dielectric or a metal having a hexagonal close-packed (HCP) crystal structure, in addition to aluminum nitride (AlN). In an example, when the seed layer is a metal, the seed layer may be formed using titanium (Ti).

The lower electrode 220 may be formed on the film layer 210, and a portion thereof may be disposed on an upper portion of the cavity C. In addition, the lower electrode 220 may serve as an input electrode or an output electrode for inputting and outputting an electrical signal such as a Radio Frequency (RF) signal.

The lower electrode 220 may be formed using a conductive material such as molybdenum (Mo) or an alloy thereof; however, the present disclosure is not limited thereto, and the lower electrode 220 may be formed using a conductive material such as ruthenium (Ru), tungsten (W), iridium (Ir), platinum (Pt), copper (Cu), titanium (Ti), tantalum (Ta), nickel (Ni), chromium (Cr), or the like, or an alloy thereof.

The piezoelectric layer 230 may be formed to cover at least a portion of the position of the lower electrode 220 disposed over the cavity C. The piezoelectric layer 230 may piezoelectrically convert electrical energy into mechanical energy in the form of sound waves, and may be formed using any one of or any combination of any two or more of aluminum nitride (AlN), zinc oxide (ZnO), and lead zirconate titanate or lead zirconate titanate oxide (PZT; PbZrTiO). Specifically, when the piezoelectric layer 230 is formed using aluminum nitride (AlN), the piezoelectric layer 230 may further include a rare earth metal or a transition metal. In an example, the rare earth metal can include at least one of scandium (Sc), erbium (Er), yttrium (Y), and lanthanum (La). In addition, as an embodiment, the transition metal may include at least one of titanium (Ti), zirconium (Zr), hafnium (Hf), tantalum (Ta), and niobium (Nb). Magnesium (Mg) may also be included (magnesium (Mg) is a divalent metal).

The upper electrode 240 may be formed to cover at least a portion of the piezoelectric layer 230 disposed over the cavity C. The upper electrode 240 may serve as an input electrode or an output electrode for inputting and outputting an electrical signal such as a Radio Frequency (RF) signal. For example, when the lower electrode 220 is used as an input electrode, the upper electrode 240 may be used as an output electrode, and vice versa.

The upper electrode 240 may be formed using a conductive material such as molybdenum (Mo) or an alloy thereof; however, the present disclosure is not limited thereto, and the upper electrode 240 may be formed using a conductive material such as ruthenium (Ru), tungsten (W), iridium (Ir), platinum (Pt), copper (Cu), titanium (Ti), tantalum (Ta), nickel (Ni), chromium (Cr), or the like, or an alloy thereof.

The passivation layer 250 may be formed in an area over the lower electrode 220 and the upper electrode 240 except for a portion of the lower electrode 220 on which the first metal pad 140 is formed and a portion of the upper electrode 240 on which the second metal pad 160 is formed. The passivation layer 250 may prevent damage to the upper electrode 240 and the lower electrode 220 during the manufacturing process.

In addition, the passivation layer 250 may be partially removed by etching in a final process according to desired frequency control. For example, the thickness of the passivation layer 250 may be adjusted. Containing silicon nitride (Si) ₃N ₄) Silicon dioxide (SiO) ₂) Magnesium oxide (MgO), zirconium oxide (ZrO) ₂) Aluminum nitride (AlN), lead zirconate titanate (PZT), gallium arsenide (GaAs), hafnium oxide (HfO) ₂) Alumina (Al) ₂O ₃) Titanium oxide (TiO) ₂) And zinc oxide (ZnO), or any combination of any two or more thereof, may be used as the passivation layer 250.

The active area of the acoustic wave filter device 100 refers to an area where the lower electrode 220, the piezoelectric layer 230, and the upper electrode 240 overlap.

The first metal pad 140 may be provided in plural. The first metal pad 140 may be disposed outside the active area and may be connected to the lower electrode 220. For example, the first metal pad 140 may be connected to the lower electrode 220 disposed in the adjacent resonance part 200. However, only a portion of the plurality of first metal pads 140 may include an annular portion or peripheral portion 142 disposed to surround the active area. In other words, a portion of the plurality of first metal pads 140 or selected ones of the first metal pads 140 may respectively have a ring portion 142 disposed to surround the active area without interfering with the second metal pads 160. The unselected remaining portions of the plurality of first metal pads 140 may not have the ring portion 142.

The first metal pad 140 excluding the loop portion 142 may be formed to be relatively small in size as an imaginary band connecting the loop portions 142. For example, in an example in which the first metal pad 140 does not include the ring part 142, an imaginary band shape connecting the ring parts 142 extending from both sides of the first metal pad 140 and the ring parts 142 extending from both sides of the first metal pad 140 may be removed from the first metal pad 140. The detailed description thereof will be further described later.

For example, the first metal pad 140 may be formed using a material such as gold (Au), gold-tin (Au-Sn) alloy, copper (Cu), copper-tin (Cu-Sn) alloy, aluminum (Al), aluminum alloy, or the like. For example, the aluminum alloy may be an aluminum-germanium (Al-Ge) alloy.

The second metal pad 160 may be provided in a plurality as a plurality of second metal pads 160. The second metal pad 160 may be disposed outside the active area and may be connected to the upper electrode 240. For example, the second metal pad 160 may be connected to the upper electrode 240 disposed in the adjacent resonance part 200. However, all of the plurality of second metal pads 160 do not have a configuration corresponding to the ring portion 142 of the first metal pad 140. Among the plurality of second metal pads 160, the length of the second metal pad 160 disposed opposite the first metal pad 140 having the ring part 142 may be longer than the length of the second metal pad 160 disposed opposite the first metal pad 140 not having the ring part 142. The detailed description thereof will be further described later.

For example, the second metal pad 160 may be formed using a material such as gold (Au), gold-tin (Au-Sn) alloy, copper (Cu), copper-tin (Cu-Sn) alloy, aluminum (Al), aluminum alloy, or the like. For example, the aluminum alloy may be an aluminum-germanium (Al-Ge) alloy.

Since the second metal pad 160 does not have a configuration corresponding to the ring portion 142, the size of the second metal pad 160 can be reduced. Accordingly, resistance can be reduced and thus electrical performance can be improved.

Further, the upper electrode 240 includes a frame portion 242 disposed at an edge of the active area, and the ring portion 142 of the first metal pad 140 is disposed outside the frame portion 242.

Hereinafter, a difference in performance between the resonance part connected to the first metal pad having the ring part and the resonance part connected to the first metal pad not having the ring part will be described with reference to the drawings.

Fig. 3 is a plan view showing an example of the resonance section connected to the first metal pad having the ring section, and fig. 4 is a plan view showing an example of the resonance section connected to the first metal pad having no ring section.

Referring to fig. 3, the first metal pad 140 may include the ring portion 142, and the second metal pad 160 may not include a configuration corresponding to the ring portion 142. As an example, the distance between the reference positions (the centers of the circular pads disposed at the upper and lower portions) may be 402.7 μm.

Referring to fig. 4, the first and second metal pads 140 and 160 do not include the ring portion 142. As an example, the distance between the reference positions (the centers of the circular pads disposed at the upper and lower portions) may be 336.1 μm.

Referring to the above, in more detail, the first metal pad 140 (as shown in fig. 4) excluding the ring part 142 may be formed relatively small compared to the size of the first metal pad 140 including the ring part 142. For example, in an example of the first metal pad 140 without the ring portion 142 (as shown in fig. 4), an imaginary band shape connecting the ring portions 142 extending from both sides of the first metal pad 140 and the ring portions 142 extending from both sides of the first metal pad 140 (as shown in fig. 3) may be removed from the first metal pad 140. Accordingly, the size of the first metal pad 140 (as shown in fig. 4) without the ring part 142 may be formed to be relatively smaller than the size of the first metal pad 140 (as shown in fig. 3) including the ring part 142.

The size of the second metal pad 160 disposed opposite the first metal pad 140 (shown in fig. 3) including the loop part 142 may be formed to be larger than the size of the second metal pad 160 disposed opposite the first metal pad 140 (shown in fig. 4) without the loop part 142.

For example, an imaginary band shape extending from the ring part 142 in the second metal pad 160 disposed opposite to the first metal pad 140 having the ring part 142 (as shown in fig. 3) may be removed from the second metal pad 160 disposed opposite to the first metal pad 140 having the ring part 142 to form the second metal pad 160 shown in fig. 4.

In addition, the present disclosure is not limited thereto, and the first metal pad 140 may be connected to the upper electrode 240 and the second metal pad 160 may be connected to the lower electrode 220. Further, an annular portion or peripheral portion 142 disposed outside the active area may also be formed as part of the second metal pad 160 while the first metal pad 140 does not have the annular portion 142.

As shown in fig. 5, the waveform of the resonance portion shown in fig. 3 is similar to that of the resonance portion shown in fig. 4.

As shown in fig. 6, the performance of the resonance portion shown in fig. 3 at the resonance point is similar to that of the resonance portion shown in fig. 4 at the resonance point. For example, fluctuations in the resonant frequency may not appear significantly within 0.15MHz, and the loss at the resonant point may be reduced slightly from-0.094 dB to-0.107 dB.

Further, as shown in fig. 7, the performance of the resonance portion shown in fig. 3 at the anti-resonance point is substantially the same as the performance of the resonance portion shown in fig. 4 at the anti-resonance point. For example, it can be seen that fluctuations in the antiresonance frequency may not occur significantly within 0.05MHz, and the loss at the antiresonance point may be reduced slightly from-37.228 dB to-37.235 dB.

However, as shown in fig. 4, it can be seen that an area reduction of about 16% in the layout can be achieved.

Hereinafter, modified embodiments of the resonance part will be described with reference to the drawings. The first and second metal pads are denoted by the same reference numerals, and detailed description thereof will be omitted.

Fig. 8 is a schematic sectional view showing an example of the resonance portion.

Referring to fig. 8, in one example, the resonance part 300 may include a sacrificial layer 320, an etch prevention part 330, a film layer 340, a lower electrode 350, a piezoelectric layer 360, an upper electrode 370, an insertion layer 380, and a passivation layer 390.

The sacrificial layer 320 may be formed on the insulating layer 312 on the substrate 310, and the cavity C and the etch stopper 330 may be disposed in an inward direction of the sacrificial layer 320. The cavity C may be formed by removing a portion of the sacrificial layer 320 during the manufacturing process. As described above, since the cavity C is formed in the inward direction of the sacrificial layer 320, the lower electrode 350 or the like disposed at a position above the sacrificial layer 320 may be formed in a flat shape.

The etch stopper 330 may be disposed along a boundary of the cavity C. The etch stopper 330 may prevent the etch from proceeding to an area beyond the cavity in the process of forming the cavity C.

The cavity C may be formed between the film layer 340 and the substrate 310. In addition, the film layer 340 may be formed using a material having low reactivity with an etching gas when the sacrificial layer 320 is removed. The etch stopper 330 may be inserted into the groove 342 formed by the film layer 340. Containing silicon nitride (Si) ₃N ₄) Silicon dioxide (SiO) ₂) Magnesium oxide (MgO), zirconium oxide (ZrO) ₂) Aluminum nitride (AlN), lead zirconate titanate (PZT), gallium arsenide (GaAs), hafnium oxide (HfO) ₂) Alumina (Al) ₂O ₃) Titanium oxide (TiO) ₂) And zinc oxide (ZnO), or any combination of any two or more thereof, may be used as the film layer 340.

A seed layer (not shown) formed using aluminum nitride (AlN) may be formed on the film layer 340. For example, a seed layer may be disposed between the film layer 340 and the lower electrode 350. The seed layer may be formed using a dielectric or a metal having an HCP crystal structure, in addition to aluminum nitride (AlN). As an example, when the seed layer is a metal, the seed layer may be formed using titanium (Ti).

The lower electrode 350 may be formed on the film layer 340, and a portion thereof may be disposed on an upper portion of the cavity C. In addition, the lower electrode 350 may serve as an input electrode or an output electrode for inputting and outputting an electrical signal such as a Radio Frequency (RF) signal.

The lower electrode 350 may be formed using a conductive material such as molybdenum (Mo) or an alloy thereof; however, the present disclosure is not limited thereto, and the lower electrode 350 may be formed using a conductive material such as ruthenium (Ru), tungsten (W), iridium (Ir), platinum (Pt), copper (Cu), titanium (Ti), tantalum (Ta), nickel (Ni), chromium (Cr), or the like, or an alloy thereof.

The piezoelectric layer 360 may be formed to cover at least a portion of the position of the lower electrode 350 disposed over the cavity C. The piezoelectric layer 360 may be a portion that generates a piezoelectric effect for converting electric energy into mechanical energy in the form of sound waves, and may be formed using any one of aluminum nitride (AlN), zinc oxide (ZnO), and lead zirconate titanate or lead zirconate titanate oxide (PZT; PbZrTiO). Specifically, when the piezoelectric layer 360 is formed using aluminum nitride (AlN), the piezoelectric layer 360 may further include a rare earth metal or a transition metal. As an example, the rare earth metal may include at least one of scandium (Sc), erbium (Er), yttrium (Y), and lanthanum (La). Further, as an embodiment, the transition metal may include at least one of titanium (Ti), zirconium (Zr), hafnium (Hf), tantalum (Ta), and niobium (Nb). Magnesium (Mg) may also be included (magnesium (Mg) is a divalent metal).

The piezoelectric layer 360 may include a piezoelectric portion 362 provided in the flat portion S and a curved portion 364 provided in the extension portion E.

The piezoelectric portion 362 may be a portion directly stacked on the upper surface of the lower electrode 350. Accordingly, the piezoelectric portion 362 may be disposed between the lower electrode 350 and the upper electrode 370, and may be formed in a flat shape together with the lower electrode 350 and the upper electrode 370.

The bent portion 364 may be defined as a portion extending in an outward direction from the piezoelectric portion 362, and may be located in the extension portion E.

The bent portion 364 may be provided on an insertion layer 380, which will be described later, and may be formed in a shape that is raised along the shape of the insertion layer 380. The piezoelectric layer 360 may be bent at a boundary between the piezoelectric portion 362 and the bent portion 364, and the bent portion 364 may be raised corresponding to the thickness and shape of the insertion layer 380.

The bent portion 364 may be divided into an inclined portion 364a and an extended portion 364 b.

The inclined portion 364a refers to a portion formed to be inclined along an inclined surface L of the insertion layer 380, which will be described further later. The extension 364b refers to a portion extending in an outward direction from the inclined portion 364 a.

The inclined portion 364a may be formed parallel to the inclined surface L of the insertion layer 380, and the inclined portion 364a may be formed at an inclined angle (θ in fig. 8) equal to the inclined surface L of the insertion layer 380.

The upper electrode 370 may be formed to cover at least a portion of the piezoelectric layer 360 disposed at a position above the cavity C. The upper electrode 370 may serve as an input electrode or an output electrode for inputting and outputting an electrical signal such as a Radio Frequency (RF) signal. For example, when the lower electrode 350 is used as an input electrode, the upper electrode 370 may be used as an output electrode, and when the lower electrode 350 is used as an output electrode, the upper electrode 370 may be used as an input electrode.

The upper electrode 370 may be formed using a conductive material such as molybdenum (Mo) or an alloy thereof; however, the present disclosure is not limited thereto, and the upper electrode 370 may be formed using a conductive material such as ruthenium (Ru), tungsten (W), iridium (Ir), platinum (Pt), copper (Cu), titanium (Ti), tantalum (Ta), nickel (Ni), chromium (Cr), or the like, or an alloy thereof.

An intervening layer 380 may be disposed between the lower electrode 350 and the piezoelectric layer 360. The insertion layer 380 may utilize materials such as silicon dioxide (SiO) ₂) Aluminum nitride (AlN), aluminum oxide (Al) ₂O ₃) Silicon nitride (Si) ₃N ₄) Magnesium oxide (MgO), zirconium oxide (ZrO) ₂) Lead zirconate titanate (PZT), gallium arsenide (GaAs), hafnium oxide (HfO) ₂) Titanium oxide (TiO) ₂) And zinc oxide (ZnO), but may be formed using a material different from that of the piezoelectric layer 360. Further, if necessary, the region provided with the insertion layer 380 may be formed as an air pocket (air pocket). This may be accomplished by removing the insertion layer 380 during the manufacturing process.

In this example, the insertThe thickness of the implant layer 380 may be the same as or similar to the thickness of the lower electrode 350. The interposer 380 may be formed thinner than the piezoelectric layer 360 or may be formed similar to the piezoelectric layer 360. For example, the interposer 380 can be formed with

Or a greater thickness, and may be formed thinner than the thickness of the piezoelectric layer 360. The configuration of the present disclosure may not be limited thereto.

The insertion layer 380 may be disposed along a surface formed by the film layer 340, the lower electrode 350, and the etch stopper 330.

An intervening layer 380 may be disposed around the flat portion S to support the curved portion 364 of the piezoelectric layer 360. Accordingly, the bending portion 364 of the piezoelectric layer 360 may be divided into the inclined portion 364a and the extended portion 364b according to the shape of the insertion layer 380.

The insertion layer 380 may be disposed in an area other than the flat portion S. For example, the insertion layer 380 may be disposed over the entire area except for the flat portion S, or may be disposed in a partial area except for the flat portion S.

At least a portion of the intervening layer 380 may be disposed between the piezoelectric layer 360 and the lower electrode 350.

The side surface of the insertion layer 380 disposed along the boundary of the flat portion S may be formed in a thicker form as the distance from the flat portion S increases. The side surface of the insertion layer 380 may be formed of the inclined surface L such that the side surface of the insertion layer 380 disposed adjacent to the flat portion S has a constant inclination angle θ.

In order to manufacture the insertion layer 380, when the inclination angle θ of the side surface of the insertion layer 380 is less than 5 degrees, the thickness of the insertion layer 380 may become very thin or the region of the inclined surface L may be excessively large, which may make the insertion layer 380 difficult to manufacture.

In addition, when the inclination angle θ of the side surface of the insertion layer 380 is formed to be greater than 70 degrees, the inclination angle of the inclined portion 364a of the piezoelectric layer 360 stacked on the insertion layer 380 may be formed to be greater than 70 degrees. In such an example, since the piezoelectric layer 360 may be excessively bent, cracks may occur in the bent portion of the piezoelectric layer 360.

Therefore, in the present example, the inclination angle θ of the inclined surface L may be formed in a range of 5 degrees or more and 70 degrees or less, for example, in a range between 5 degrees and 70 degrees.

A passivation layer 390 may be formed in an area over the lower electrode 350 and the upper electrode 370 except for a portion of the lower electrode 350 on which the first metal pad 140 is formed and a portion of the upper electrode 370 on which the second metal pad 160 is formed. The passivation layer 390 may prevent damage to the upper and lower electrodes 370 and 350 during a manufacturing process.

In addition, the passivation layer 390 may be partially removed in a final process by etching according to a desired frequency control. For example, the thickness of the passivation layer 390 may be adjusted. Containing silicon nitride (Si) ₃N ₄) Silicon dioxide (SiO) ₂) Magnesium oxide (MgO), zirconium oxide (ZrO) ₂) Aluminum nitride (AlN), lead zirconate titanate (PZT), gallium arsenide (GaAs), hafnium oxide (HfO) ₂) Alumina (Al) ₂O ₃) Titanium oxide (TiO) ₂) And zinc oxide (ZnO) may be used as an example of the passivation layer 390.

While the present disclosure includes particular examples, it will be apparent, after understanding the disclosure of the present application, that various changes in form and detail may be made therein without departing from the spirit and scope of the claims and their equivalents. The examples described herein are to be considered in a descriptive sense only and not for purposes of limitation. The description of features or aspects in each example will be considered applicable to similar features or aspects in other examples. Suitable results may be obtained if the described techniques are performed in a different order and/or if components in the described systems, architectures, devices, or circuits are combined in a different manner and/or replaced or supplemented by other components or their equivalents. Therefore, the scope of the present disclosure is defined not by the detailed description but by the claims and their equivalents, and all changes within the scope of the claims and their equivalents are to be construed as being included in the present disclosure.