CN113872549B - Method for manufacturing bulk acoustic wave resonator, bulk acoustic wave resonator and filter - Google Patents
Method for manufacturing bulk acoustic wave resonator, bulk acoustic wave resonator and filter Download PDFInfo
- Publication number
- CN113872549B CN113872549B CN202111457537.7A CN202111457537A CN113872549B CN 113872549 B CN113872549 B CN 113872549B CN 202111457537 A CN202111457537 A CN 202111457537A CN 113872549 B CN113872549 B CN 113872549B
- Authority
- CN
- China
- Prior art keywords
- layer
- single crystal
- crystal piezoelectric
- lower electrode
- resonator
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 42
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 21
- 239000013078 crystal Substances 0.000 claims abstract description 116
- 229910052751 metal Inorganic materials 0.000 claims abstract description 85
- 239000002184 metal Substances 0.000 claims abstract description 85
- 238000000151 deposition Methods 0.000 claims abstract description 29
- 239000004020 conductor Substances 0.000 claims description 41
- 239000000463 material Substances 0.000 claims description 27
- 239000000758 substrate Substances 0.000 claims description 24
- 238000002161 passivation Methods 0.000 claims description 23
- PMHQVHHXPFUNSP-UHFFFAOYSA-M copper(1+);methylsulfanylmethane;bromide Chemical compound Br[Cu].CSC PMHQVHHXPFUNSP-UHFFFAOYSA-M 0.000 claims description 12
- 238000005530 etching Methods 0.000 claims description 12
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 claims description 10
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 6
- 239000000919 ceramic Substances 0.000 claims description 5
- 239000011787 zinc oxide Substances 0.000 claims description 5
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 3
- 229910052759 nickel Inorganic materials 0.000 claims description 3
- 239000010936 titanium Substances 0.000 claims description 3
- 229910052719 titanium Inorganic materials 0.000 claims description 3
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 abstract description 11
- 229910052710 silicon Inorganic materials 0.000 abstract description 11
- 239000010703 silicon Substances 0.000 abstract description 11
- 238000010586 diagram Methods 0.000 description 14
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 9
- 229910052737 gold Inorganic materials 0.000 description 9
- 239000010931 gold Substances 0.000 description 9
- 239000010949 copper Substances 0.000 description 6
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 5
- 229910052802 copper Inorganic materials 0.000 description 5
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 description 4
- 238000005229 chemical vapour deposition Methods 0.000 description 4
- 238000005240 physical vapour deposition Methods 0.000 description 4
- 229910002601 GaN Inorganic materials 0.000 description 3
- JMASRVWKEDWRBT-UHFFFAOYSA-N Gallium nitride Chemical compound [Ga]#N JMASRVWKEDWRBT-UHFFFAOYSA-N 0.000 description 3
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 3
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 3
- 229910052782 aluminium Inorganic materials 0.000 description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 3
- 229910052732 germanium Inorganic materials 0.000 description 3
- GNPVGFCGXDBREM-UHFFFAOYSA-N germanium atom Chemical compound [Ge] GNPVGFCGXDBREM-UHFFFAOYSA-N 0.000 description 3
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 3
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 3
- 229910010271 silicon carbide Inorganic materials 0.000 description 3
- 229910052718 tin Inorganic materials 0.000 description 3
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 2
- 238000009713 electroplating Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 229910052738 indium Inorganic materials 0.000 description 2
- APFVFJFRJDLVQX-UHFFFAOYSA-N indium atom Chemical compound [In] APFVFJFRJDLVQX-UHFFFAOYSA-N 0.000 description 2
- 230000003071 parasitic effect Effects 0.000 description 2
- 238000005498 polishing Methods 0.000 description 2
- 229910052594 sapphire Inorganic materials 0.000 description 2
- 239000010980 sapphire Substances 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 229910052709 silver Inorganic materials 0.000 description 2
- 239000004332 silver Substances 0.000 description 2
- 239000011135 tin Substances 0.000 description 2
- 238000003631 wet chemical etching Methods 0.000 description 2
- 238000001039 wet etching Methods 0.000 description 2
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 1
- KJTLSVCANCCWHF-UHFFFAOYSA-N Ruthenium Chemical compound [Ru] KJTLSVCANCCWHF-UHFFFAOYSA-N 0.000 description 1
- 229910052581 Si3N4 Inorganic materials 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000001312 dry etching Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005496 eutectics Effects 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 239000011733 molybdenum Substances 0.000 description 1
- 239000012811 non-conductive material Substances 0.000 description 1
- 229910052763 palladium Inorganic materials 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 229910052707 ruthenium Inorganic materials 0.000 description 1
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 1
- 229910052814 silicon oxide Inorganic materials 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 229910052715 tantalum Inorganic materials 0.000 description 1
- GUVRBAGPIYLISA-UHFFFAOYSA-N tantalum atom Chemical compound [Ta] GUVRBAGPIYLISA-UHFFFAOYSA-N 0.000 description 1
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 239000010937 tungsten Substances 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H3/00—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators
- H03H3/007—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators for the manufacture of electromechanical resonators or networks
- H03H3/02—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators for the manufacture of electromechanical resonators or networks for the manufacture of piezoelectric or electrostrictive resonators or networks
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/46—Filters
- H03H9/54—Filters comprising resonators of piezoelectric or electrostrictive material
- H03H9/56—Monolithic crystal filters
- H03H9/564—Monolithic crystal filters implemented with thin-film techniques
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/46—Filters
- H03H9/54—Filters comprising resonators of piezoelectric or electrostrictive material
- H03H9/58—Multiple crystal filters
- H03H9/582—Multiple crystal filters implemented with thin-film techniques
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H3/00—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators
- H03H3/007—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators for the manufacture of electromechanical resonators or networks
- H03H3/02—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators for the manufacture of electromechanical resonators or networks for the manufacture of piezoelectric or electrostrictive resonators or networks
- H03H2003/023—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators for the manufacture of electromechanical resonators or networks for the manufacture of piezoelectric or electrostrictive resonators or networks the resonators or networks being of the membrane type
Landscapes
- Chemical & Material Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Piezo-Electric Or Mechanical Vibrators, Or Delay Or Filter Circuits (AREA)
Abstract
The application relates to the technical field of resonators, and discloses a method for manufacturing a bulk acoustic wave resonator, which comprises the following steps: depositing a single crystal piezoelectric layer on a preset layer to be removed; manufacturing a resonant structure on one side of the single crystal piezoelectric layer far away from the layer to be removed; forming a first metal layer on the resonant structure; bonding a first metal layer on the resonator carrier; removing the layer to be removed; forming an upper electrode structure on one side of the resonant structure far away from the first metal layer; a cavity is formed within the resonant structure. Therefore, the resonant structure and the resonator carrier are subjected to metal bonding through the metal layer, and the bonding between the metal and the metal can be performed under the condition of larger wafer warping degree compared with the conventional SiO2-Si bonding mode, so that the resonant structure and the resonator carrier can be bonded under the condition of large silicon-based wafer warping degree. The application also discloses a bulk acoustic wave resonator and a filter.
Description
Technical Field
The present invention relates to the field of resonator technology, and for example, to a method for manufacturing a bulk acoustic wave resonator, and a filter.
Background
At present, in the process of manufacturing the bulk acoustic wave resonator, the resonant structure and the resonator carrier are usually manufactured firstly, and then the resonant structure and the resonator carrier are bonded, so that the resonator carrier can support the resonant structure. In order to enable the performance of the bulk acoustic wave resonator to be better, a single crystal piezoelectric layer with higher quality or narrower half-peak XRD width is needed, and a single crystal piezoelectric layer with higher quality or narrower half-peak XRD width is used, so that the warpage of a silicon-based wafer is large, and the traditional SiO2-Si bonding mode needs to be carried out under the condition that the warpage of the silicon-based wafer is small, so that the traditional bonding mode is not suitable for being used for bonding with a resonator carrier under the condition that the warpage of the silicon-based wafer is large.
Disclosure of Invention
The following presents a simplified summary in order to provide a basic understanding of some aspects of the disclosed embodiments. This summary is not an extensive overview nor is intended to identify key/critical elements or to delineate the scope of such embodiments but rather as a prelude to the more detailed description that is presented later.
The embodiment of the invention provides a method for manufacturing a bulk acoustic wave resonator, a bulk acoustic wave resonator and a filter, which can bond a resonant structure and a resonator carrier under the condition of large warpage of a silicon-based wafer.
In some embodiments, a method for bulk acoustic wave resonator fabrication includes: depositing a single crystal piezoelectric layer on a preset layer to be removed; the layer to be removed comprises a substrate to be removed and a single crystal buffer layer; the single crystal buffer layer is made of a material matched with the lattice structure and lattice constant of the material of the single crystal piezoelectric layer; the single crystal piezoelectric layer is made of aluminum nitride, zinc oxide or piezoelectric ceramic; manufacturing a resonant structure on one side of the single crystal piezoelectric layer far away from the layer to be removed; forming a first metal layer on the resonant structure; bonding the first metal layer on a resonator carrier; removing the layer to be removed; forming an upper electrode structure on one side of the resonant structure far away from the first metal layer; a cavity is formed within the resonant structure.
In some embodiments, the bulk acoustic wave resonator is manufactured by the method for manufacturing the bulk acoustic wave resonator.
In some embodiments, the filter comprises a bulk acoustic wave resonator as described above.
The method for manufacturing the bulk acoustic wave resonator, the bulk acoustic wave resonator and the filter provided by the embodiment of the invention can realize the following technical effects: depositing a single crystal piezoelectric layer on a preset layer to be removed; the layer to be removed comprises a substrate to be removed and a single crystal buffer layer; the single crystal buffer layer is made of a material matched with the lattice structure and lattice constant of the material of the single crystal piezoelectric layer; the single crystal piezoelectric layer is made of aluminum nitride, zinc oxide or piezoelectric ceramics; manufacturing a resonant structure on one side of the single crystal piezoelectric layer far away from the layer to be removed; forming a first metal layer on the resonant structure; bonding a first metal layer on the resonator carrier; removing the layer to be removed; forming an upper electrode structure on one side of the resonant structure far away from the first metal layer; a cavity is formed within the resonant structure. In this way, by fabricating the single crystal piezoelectric layer on the single crystal buffer layer made of a material in which the lattice structure and the lattice constant of the material of the piezoelectric layer are matched, the crystal quality of the single crystal piezoelectric layer can be improved. Meanwhile, the resonant structure and the resonator carrier are subjected to metal bonding through the metal layer, and the bonding between the metal and the metal can be performed under the condition of larger wafer warping degree compared with the conventional SiO2-Si bonding mode, so that the resonant structure and the resonator carrier can be bonded under the condition of large silicon-based wafer warping degree.
The foregoing general description and the following description are exemplary and explanatory only and are not restrictive of the application.
Drawings
One or more embodiments are illustrated by way of example in the accompanying drawings, which correspond to the accompanying drawings and not in limitation thereof, in which elements having the same reference numeral designations are shown as like elements and not in limitation thereof, and wherein:
FIG. 1 is a schematic diagram of a method for fabricating a bulk acoustic wave resonator according to an embodiment of the present invention;
FIG. 2 is a schematic structural diagram of a layer to be removed according to an embodiment of the present invention;
FIG. 3 is a schematic structural diagram of a single crystal piezoelectric layer, a lower electrode layer and a first passivation layer deposited on a layer to be removed according to an embodiment of the present invention;
FIG. 4 is a schematic structural diagram of a lower electrode layer and a first passivation layer etched according to an embodiment of the present invention;
FIG. 5 is a schematic structural diagram illustrating a lower electrode structure after a sacrificial layer is deposited thereon according to an embodiment of the present invention;
FIG. 6 is a schematic structural diagram of a sacrificial layer after etching according to an embodiment of the present invention;
FIG. 7 is a schematic structural diagram of a post-etch sacrificial layer with a cut-off boundary layer deposited thereon according to an embodiment of the present invention;
FIG. 8 is a schematic diagram of a structure after a first sacrificial layer is deposited on a cut-off boundary layer according to an embodiment of the present invention;
FIG. 9 is a schematic diagram of a structure after depositing a first metal layer on a first sacrificial layer according to an embodiment of the present invention;
FIG. 10 is a schematic diagram of a resonator carrier according to an embodiment of the present invention;
FIG. 11 is a schematic diagram of a structure after bonding a first metal layer to a resonator carrier according to an embodiment of the present invention;
FIG. 12 is a schematic diagram illustrating a structure after a layer to be removed is removed according to an embodiment of the present invention;
fig. 13 is a schematic structural diagram of a single crystal piezoelectric layer with an upper electrode structure formed thereon according to an embodiment of the present invention;
fig. 14 is a schematic structural diagram of a resonator provided in an embodiment of the present invention.
Reference numerals:
100: the substrate is to be removed; 110: a monocrystalline buffer layer; 120: a single crystal epitaxial layer; 130: a single crystal piezoelectric layer; 140: a lower electrode layer; 150: a first passivation layer; 160: a first sacrificial layer; 170: stopping the boundary layer; 180: a second sacrificial layer; 190: a first metal layer; 200: a resonator carrier substrate; 210: a filling layer; 220: a second metal layer; 230: an upper electrode layer; 240: a second passivation layer; 250: a first conductor; 260: a second conductor; 270: a third conductor.
Detailed Description
So that the manner in which the features and aspects of the embodiments of the present invention can be understood in detail, a more particular description of the embodiments of the invention, briefly summarized above, may be had by reference to the embodiments, some of which are illustrated in the appended drawings. In the following description of the technology, for purposes of explanation, numerous details are set forth in order to provide a thorough understanding of the disclosed embodiments. However, one or more embodiments may be practiced without these details. In other instances, well-known structures and devices may be shown in simplified form in order to simplify the drawing.
The terms "first," "second," and the like in the description and in the claims, and in the drawings, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It should be understood that the data so used may be interchanged under appropriate circumstances such that embodiments of the invention described herein may be used. Furthermore, the terms "comprising" and "having," as well as any variations thereof, are intended to cover non-exclusive inclusions.
In the embodiments of the present invention, the terms "upper", "lower", "inner", "middle", "outer", "front", "rear", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings. These terms are used primarily to better describe embodiments of the invention and its embodiments, and are not intended to limit the indicated devices, elements or components to a particular orientation or to be constructed and operated in a particular orientation. Moreover, some of the above terms may be used to indicate other meanings besides the orientation or positional relationship, for example, the term "on" may also be used to indicate some kind of attachment or connection relationship in some cases. Specific meanings of these terms in the embodiments of the present invention may be understood by those skilled in the art according to specific situations.
In addition, the terms "disposed," "connected," and "secured" are to be construed broadly. For example, "connected" may be a fixed connection, a detachable connection, or a unitary construction; can be a mechanical connection, or an electrical connection; may be directly connected, or indirectly connected through intervening media, or may be in internal communication between two devices, elements or components. Specific meanings of the above terms in the embodiments of the present invention can be understood by those of ordinary skill in the art according to specific situations.
The term "plurality" means two or more unless otherwise specified.
In the embodiment of the present invention, the character "/" indicates that the preceding and following objects are in an or relationship. For example, A/B represents: a or B.
The term "and/or" is an associative relationship that describes objects, meaning that three relationships may exist. For example, a and/or B, represents: a or B, or A and B.
It should be noted that, in the case of no conflict, the embodiments of the present invention and features of the embodiments may be combined with each other.
As shown in fig. 1, an embodiment of the present invention provides a method for manufacturing a bulk acoustic wave resonator,
step S101, depositing a single crystal piezoelectric layer on a preset layer to be removed; the layer to be removed comprises a substrate to be removed and a single crystal buffer layer; the single crystal buffer layer is made of a material matched with the lattice structure and lattice constant of the material of the single crystal piezoelectric layer; the single crystal piezoelectric layer is made of aluminum nitride, zinc oxide or piezoelectric ceramics;
step S102, manufacturing a resonance structure on one side of the single crystal piezoelectric layer far away from the layer to be removed;
step S103, forming a first metal layer on the resonance structure;
step S104, bonding a first metal layer on the resonator carrier;
step S105, removing the layer to be removed;
step S105, forming an upper electrode structure on one side of the resonance structure far away from the first metal layer;
and step S106, forming a cavity in the resonant structure.
By adopting the method for manufacturing the bulk acoustic wave resonator provided by the embodiment of the invention, the single crystal piezoelectric layer is deposited on the preset layer to be removed; the layer to be removed comprises a substrate to be removed and a single crystal buffer layer; the single crystal buffer layer is made of a material matched with the lattice structure and lattice constant of the material of the single crystal piezoelectric layer; the single crystal piezoelectric layer is made of aluminum nitride, zinc oxide or piezoelectric ceramics; manufacturing a resonant structure on one side of the single crystal piezoelectric layer far away from the layer to be removed; forming a first metal layer on the resonant structure; bonding a first metal layer on the resonator carrier; removing the layer to be removed; forming an upper electrode structure on one side of the resonant structure far away from the first metal layer; a cavity is formed within the resonant structure. In this way, by fabricating the single crystal piezoelectric layer on the single crystal buffer layer made of a material in which the lattice structure and the lattice constant of the material of the piezoelectric layer are matched, the crystal quality of the single crystal piezoelectric layer can be improved. Meanwhile, the resonant structure and the resonator carrier are subjected to metal bonding through the metal layer, and the bonding between the metal and the metal can be performed under the condition of larger wafer warping degree compared with the conventional SiO2-Si bonding mode, so that the resonant structure and the resonator carrier can be bonded under the condition of large silicon-based wafer warping degree.
In some embodiments, the single crystal piezoelectric layer is deposited on the predetermined layer to be removed by a CVD (Chemical Vapor Deposition) process and/or a PVD (Physical Vapor Deposition) process.
Optionally, the resonant structure is formed by: forming a lower electrode structure on one side of the single crystal piezoelectric layer far away from the layer to be removed; and forming a cavity structure to be corroded on one side of the lower electrode structure, which is far away from the single crystal piezoelectric layer, and forming a resonance structure by the lower electrode structure and the cavity structure to be corroded.
In some embodiments, the predetermined layer to be removed includes a substrate to be removed, a single crystal buffer layer formed on the substrate to be removed.
With reference to fig. 2, optionally, depositing a single crystal piezoelectric layer on a predetermined layer to be removed; the preset layer to be removed includes a substrate to be removed 100, a single crystal buffer layer 110 formed on the substrate to be removed, and a single crystal epitaxial layer 120 formed on the single crystal buffer layer 110, which are sequentially formed from bottom to top.
Alternatively, the substrate to be removed is made of silicon, silicon carbide, or sapphire.
Optionally, the monocrystalline buffer layer is made of a material that matches the lattice structure and lattice constant of the material of the monocrystalline epitaxial layer.
Optionally, the single crystal buffer layer is made of a material that matches the lattice structure and lattice constant of the material of the single crystal piezoelectric layer.
Optionally, the material from which the single crystal epitaxial layer is made is matched to the lattice structure and lattice constant of the material of the single crystal piezoelectric layer.
In some embodiments, the material of the single crystal epitaxial layer is aluminum nitride, and the single crystal buffer layer is made of aluminum nitride or gallium nitride selected to match the lattice structure and lattice constant of the material of the single crystal epitaxial layer.
In some embodiments, the single crystal piezoelectric layer is made of aluminum nitride, the single crystal epitaxial layer is made of gallium nitride matched with the lattice structure and lattice constant of the aluminum nitride, and the single crystal buffer layer is made of aluminum nitride matched with the lattice structure and lattice constant of the gallium nitride.
Therefore, the single crystal piezoelectric layer with high quality can be obtained by selecting a material with a lattice structure and a lattice constant matched with those of the material of the single crystal piezoelectric layer to prepare the single crystal epitaxial layer and then preparing the single crystal piezoelectric layer on the single crystal epitaxial layer. And selecting a material with a lattice structure and a lattice constant matched with those of the material of the single crystal epitaxial layer to manufacture a single crystal buffer layer, and then manufacturing the single crystal epitaxial layer on the single crystal buffer layer, so that the high-quality single crystal epitaxial layer can be grown.
As shown in fig. 3 and 4, optionally, forming a lower electrode structure on a side of the single crystal piezoelectric layer away from the layer to be removed includes: depositing a lower electrode layer 140 on the side of the single crystal piezoelectric layer 130 away from the layer to be removed; depositing a first passivation layer 150 on the side of the lower electrode layer 140 away from the single crystal piezoelectric layer 130; the lower electrode layer 140 and the first passivation layer 150 are etched to expose the single crystal piezoelectric layer 130. And forming a lower electrode structure by the etched lower electrode layer and the first passivation layer. In this way, the first passivation layer is deposited on the side of the lower electrode layer away from the single crystal piezoelectric layer, so that the lower electrode layer can be protected by the first passivation layer, and the lower electrode layer is prevented from being oxidized, thereby preventing the function of the resonator from being affected.
Optionally, the lower electrode layer and the first passivation layer are etched by a wet chemical etching process and/or a plasma-activated etching process.
Alternatively, the lower electrode layer is made of one or more of metal materials having conductive properties such as molybdenum Mo, aluminum Al, copper Cu, platinum Pt, tantalum Ta, tungsten W, palladium Pd, and ruthenium Ru.
Optionally, the first passivation layer is made of a non-conductive material, such as: silicon nitride, aluminum nitride, and the like.
Optionally, forming a cavity structure to be etched on a side of the lower electrode structure away from the single crystal piezoelectric layer includes: depositing a first sacrificial layer on the lower electrode structure and the single crystal piezoelectric layer; etching the first sacrificial layer to form a sacrificial island on the lower electrode structure; depositing a cut-off boundary layer on one side of the sacrificial island far away from the lower electrode structure to form a cavity enclosing structure consisting of the lower electrode structure, the sacrificial island and the cut-off boundary layer; and depositing a second sacrificial layer on the cavity enclosing structure, and forming a cavity structure to be corroded by the sacrificial island, the cut-off boundary layer and the second sacrificial layer.
As shown in connection with fig. 5, optionally, depositing a first sacrificial layer 160 on the lower electrode structure and the single crystal piezoelectric layer 130 includes: a first sacrificial layer 160 is deposited on the single crystal piezoelectric layer 130 and the lower electrode structure that is not in contact with the lower electrode structure. Optionally, after depositing the first sacrificial layer, the method further includes: and carrying out planarization polishing on the first sacrificial layer. Alternatively, the first sacrificial layer is deposited by a CVD (Chemical Vapor Deposition) process and/or a PVD (Physical Vapor Deposition) process. Optionally, the first sacrificial layer is planarized and polished by CMP (chemical mechanical polishing).
In some embodiments, as shown in connection with fig. 6, the first sacrificial layer 160 is etched to form sacrificial islands on the lower electrode structure, and the etched first sacrificial layer is on the lower electrode structure and the single crystal piezoelectric layer.
In some embodiments, depositing a cutoff boundary layer on a side of the sacrificial island away from the lower electrode structure comprises: a cut-off boundary layer 170 is deposited on the side of the sacrificial island away from the lower electrode structure, the surface of the single crystal piezoelectric layer not in contact with the sacrificial island and the lower electrode structure, and the surface of the lower electrode structure not in contact with the sacrificial island, as shown in connection with fig. 7. A cavity enclosing structure is formed by the lower electrode structure, the sacrificial island and the cut-off boundary layer, and a second sacrificial layer 180 is deposited on the cavity enclosing structure, as shown in fig. 8.
In some embodiments, forming a first metal layer 190 on the resonant structure includes: a first metal layer 190 is deposited on the resonant structure as shown in connection with fig. 9. Optionally, the first metal layer is formed by an electroplating process.
In some embodiments, before depositing the first metal layer on the resonant structure, further comprising: and (4) growing a metal such as titanium, nickel and the like on the second sacrificial layer in a combined manner. In this way, the adhesion between the second sacrificial layer and the first metal layer can be increased.
As shown in connection with fig. 10, the resonator carrier optionally includes a resonator carrier substrate 200, fill layers 210 and 220, a second metal layer; fill layer 210 is located between resonator carrier substrate 200 and second metal layer 220; bonding a first metal layer on the resonator carrier, comprising: and carrying out metal bonding on the second metal layer and the first metal layer.
Optionally, the resonator carrier is formed by: depositing a filling layer on a preset resonator carrier substrate; a second metal layer is formed on the side of the fill layer remote from the resonator carrier substrate.
Optionally, the second metal layer is formed by an electroplating process.
Optionally, before depositing the second metal layer on the side of the filling layer away from the resonator carrier substrate, the method further includes: and (4) growing metals such as titanium, nickel and the like on the filling layer in a combined manner. In this way, the adhesion between the filling layer and the second metal layer can be increased.
Optionally, the resonator carrier substrate is made of silicon, silicon carbide or sapphire.
Optionally, the filler layer is made of silicon oxide or silicon carbide.
Alternatively, the first metal layer and the second metal layer are made of materials capable of metal bonding with each other, such as gold and gold, aluminum and copper, copper and copper, gold and silver, copper and tin, aluminum and germanium, gold and silicon, gold and germanium, gold and tin, gold and indium, and the like. I.e. in case the first metal layer is made of gold, the second metal layer is made of gold, silver, silicon, germanium, tin or indium.
Alternatively, the metal bond is a eutectic bond, an anodic bond, or a thermocompression bond.
In some embodiments, the first metal layer is bonded to the resonator carrier, as shown in fig. 11.
In some embodiments, the substrate to be removed is removed by a grinding process; and removing the monocrystalline buffer layer and the monocrystalline epitaxial layer by a plasma dry etching process and/or a wet chemical etching process. Referring to fig. 12, fig. 12 is a schematic structural view after a layer to be removed is removed.
As shown in fig. 13, optionally, forming an upper electrode structure on a side of the resonant structure away from the first metal layer includes: depositing an upper electrode layer 230 on a side of the single crystal piezoelectric layer 130 away from the lower electrode structure; depositing a second passivation layer 240 on a side of the upper electrode layer 230 remote from the single crystal piezoelectric layer 130; the upper electrode layer 230 and the second passivation layer 240 are etched to form an upper electrode structure, exposing the single crystalline piezoelectric layer 130. In this way, the second passivation layer is deposited on the side of the upper electrode layer remote from the single crystal piezoelectric layer, and the upper electrode layer can be protected by the second passivation layer, thereby preventing the upper electrode layer from being oxidized and preventing the function of the resonator from being affected.
As shown in fig. 14, optionally forming a cavity in the resonant structure includes: and corroding the sacrificial islands to form cavities.
Optionally, after forming the upper electrode structure on a side of the resonant structure away from the first metal layer, the method further includes: the first conductor 250 is exposed out of the second passivation layer 240 by making a connection with the upper electrode layer 230 through the first conductor 250; connecting to the lower electrode layer 140 through a second conductor 260, exposing the second conductor 260 outside the single crystal piezoelectric layer 130 that is not connected to the upper electrode structure; the third conductor 270 is exposed out of the single crystal piezoelectric layer 130 not connected to the upper electrode structure by the third conductor 270 being connected to the first metal layer 190, the third conductor 270 not being in contact with the upper electrode layer 230, the lower electrode layer 140, the sacrificial island.
Optionally, the sacrificial islands are etched by one or more of hydrofluoric acid solution wet etching, BOE (Buffered Oxide etch) solution wet etching, and hydrofluoric acid vapor etching. Therefore, the cutoff boundary layer is deposited on one side of the sacrificial island far away from the lower electrode structure, the shape of the cavity is limited by the cutoff boundary layer, and the cavity is formed by corroding the sacrificial island, so that the cavity is more convenient to manufacture.
In some embodiments, exposing the first conductor outside the second passivation layer by connecting the first conductor with the upper electrode layer includes: etching the second passivation layer to form a first through hole, wherein the first through hole is exposed out of the upper electrode layer; and forming a first conductor in the first through hole, wherein the first conductor is connected with the upper electrode layer through the first through hole.
In some embodiments, connecting to the lower electrode layer through a second conductor, exposing the second conductor outside the single crystal piezoelectric layer that is not connected to the upper electrode structure, comprises: etching the monocrystalline piezoelectric layer which is not connected with the upper electrode structure to form a second through hole, wherein the second through hole exposes the lower electrode layer; and forming a second conductor in the second through hole, wherein the second conductor is connected with the lower electrode layer through the second through hole.
In some embodiments, during use of the resonator, one end of the first conductor is connected to the upper electrode layer, and the other end is connected to an external circuit; one end of the second conductor is connected with the lower electrode layer, the other end of the second conductor is connected with the second conductor and an external circuit, and the first conductor, the second conductor and the external circuit form a loop together.
In some embodiments, connecting to the first metal layer through a third conductor, exposing the third conductor outside of the single crystal piezoelectric layer that is not connected to the upper electrode structure, comprises: etching the monocrystalline piezoelectric layer which is not contacted with the upper electrode layer and the lower electrode layer to form a third through hole, wherein the third through hole is exposed out of the cut-off boundary layer; etching the stop boundary to form a fourth through hole, wherein the fourth through hole exposes out of the second sacrificial layer and is communicated with the third through hole; etching the second sacrificial layer to form a fifth through hole, wherein the first metal layer is exposed out of the fifth through hole, and the fifth through hole is communicated with the fourth through hole; and forming a connecting through hole by the third through hole, the fourth through hole and the fifth through hole, forming a third conductor in the connecting through hole, and connecting the third conductor with the first metal layer through the connecting through hole.
In some embodiments, during use of the resonator, the end of the third conductor not connected to the first metal layer is grounded. In this way, the first metal layer and the second metal layer are added to the resonator, parasitic capacitance is brought by the first metal layer and the second metal layer, and the parasitic capacitance brought by the first metal layer and the second metal layer can be reduced or eliminated by grounding the end of the third conductor which is not connected to the first metal layer.
The embodiment of the invention provides a bulk acoustic wave resonator, which is prepared by the method for manufacturing the bulk acoustic wave resonator.
Optionally, a resonator carrier for supporting the resonant structure; the resonant structure is bonded with the resonator carrier in a metal bonding mode, and a cavity is limited in the resonant structure; a single crystal piezoelectric layer arranged on a side of the resonant structure remote from the resonator carrier; and the upper electrode structure is arranged on one side of the single crystal piezoelectric layer far away from the resonance structure.
Optionally, a third conductor is connected to the resonant structure and the single crystal piezoelectric layer, the third conductor being exposed outside the single crystal piezoelectric layer.
The embodiment of the invention provides a filter, which comprises the bulk acoustic wave resonator.
The filter provided by the embodiment of the invention is composed of the resonator using high-quality single-crystal aluminum nitride or ScAlN as the single-crystal piezoelectric layer, and the performance of the filter can be improved.
The above description and drawings sufficiently illustrate embodiments of the invention to enable those skilled in the art to practice them. Other embodiments may incorporate structural, logical, electrical, process, and other changes. The examples merely typify possible variations. Individual components and functions are optional unless explicitly required, and the sequence of operations may vary. Portions and features of some embodiments may be included in or substituted for those of others. Furthermore, the words used in the specification are words of description only and are not intended to limit the claims. As used in the description of the embodiments and the claims, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. Similarly, the term "and/or" as used in this application is meant to encompass any and all possible combinations of one or more of the associated listed. Furthermore, the terms "comprises" and/or "comprising," when used in this application, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. Without further limitation, an element defined by the phrase "comprising an …" does not exclude the presence of other identical elements in a process, method or device comprising the element. In this document, each embodiment may be described with emphasis on differences from other embodiments, and the same and similar parts between the respective embodiments may be referred to each other. For methods, products, etc. of the embodiment disclosures, reference may be made to the description of the method section for relevance if it corresponds to the method section of the embodiment disclosure.
Claims (11)
1. A method for fabricating a bulk acoustic wave resonator having a single crystal piezoelectric layer, comprising:
depositing a single crystal piezoelectric layer on a preset layer to be removed; the layer to be removed comprises a substrate to be removed and a single crystal buffer layer; the single crystal buffer layer is made of a material matched with the lattice structure and lattice constant of the material of the single crystal piezoelectric layer; the single crystal piezoelectric layer is made of aluminum nitride, zinc oxide or piezoelectric ceramic;
manufacturing a resonant structure on one side of the single crystal piezoelectric layer far away from the layer to be removed;
forming a first metal layer on the resonant structure;
bonding the first metal layer on a resonator carrier;
removing the layer to be removed;
forming an upper electrode structure on one side of the resonant structure far away from the first metal layer;
forming a cavity in the resonant structure;
the resonant structure is formed by: forming a lower electrode structure on one side of the single crystal piezoelectric layer far away from the layer to be removed; forming a cavity structure to be corroded on one side, far away from the single crystal piezoelectric layer, of the lower electrode structure, and forming a resonance structure by the lower electrode structure and the cavity structure to be corroded;
the resonator carrier is formed by: depositing a filling layer on a preset resonator carrier substrate; forming a second metal layer on one side of the filling layer far away from the resonator carrier substrate; before depositing a second metal layer on the side of the filling layer far away from the resonator carrier substrate, the method further comprises the following steps: and jointly growing titanium or nickel on the filling layer.
2. The method of claim 1, wherein forming a lower electrode structure on a side of the single crystal piezoelectric layer away from the layer to be removed comprises:
depositing a lower electrode layer on the side of the single crystal piezoelectric layer far away from the layer to be removed;
depositing a first passivation layer on the side of the lower electrode layer away from the single crystal piezoelectric layer;
and etching the lower electrode layer and the first passivation layer to expose the single crystal piezoelectric layer.
3. The method of claim 2, wherein forming a cavity structure to be etched in a side of the lower electrode structure away from the single crystal piezoelectric layer comprises:
depositing a first sacrificial layer on the lower electrode structure and the single crystal piezoelectric layer;
etching the first sacrificial layer to form a sacrificial island on the lower electrode structure;
depositing a cut-off boundary layer on one side of the sacrificial island far away from the lower electrode structure to form a cavity enclosing structure consisting of the lower electrode structure, the sacrificial island and the cut-off boundary layer;
and depositing a second sacrificial layer on the cavity enclosing structure, and forming a cavity structure to be etched by the sacrificial island, the cut-off boundary layer and the second sacrificial layer.
4. The method of claim 1, wherein the resonator carrier comprises a resonator carrier substrate, a fill layer, and a second metal layer; the fill layer is located between the resonator carrier substrate and the second metal layer; bonding the first metal layer to a resonator carrier, comprising:
and carrying out metal bonding on the second metal layer and the first metal layer.
5. The method of claim 3, wherein forming an upper electrode structure on a side of the resonant structure remote from the first metal layer comprises:
depositing an upper electrode layer on a side of the single crystal piezoelectric layer away from the lower electrode structure;
depositing a second passivation layer on a side of the upper electrode layer away from the single crystal piezoelectric layer;
and etching the upper electrode layer and the second passivation layer to form the upper electrode structure, and exposing the single crystal piezoelectric layer.
6. The method of claim 3, wherein forming a cavity within the resonant structure comprises:
and corroding the sacrificial islands to form cavities.
7. The method of claim 5, further comprising, after forming an upper electrode structure on a side of the resonant structure away from the first metal layer:
connecting the upper electrode layer with a first conductor, and exposing the first conductor outside the second passivation layer;
connecting the lower electrode layer through a second conductor, and exposing the second conductor outside the single crystal piezoelectric layer which is not connected with the upper electrode structure;
connecting with the first metal layer through a third conductor, exposing the third conductor outside the single crystal piezoelectric layer which is not connected with the upper electrode structure, wherein the third conductor is not contacted with the upper electrode layer, the lower electrode layer and the sacrificial island.
8. A bulk acoustic wave resonator, characterized in that it is manufactured by performing the method of any of claims 1 to 7.
9. The bulk acoustic wave resonator according to claim 8, comprising:
a resonator carrier for supporting a resonant structure;
the resonant structure is bonded with the resonator carrier in a metal bonding mode, and a cavity is defined in the resonant structure;
a single crystal piezoelectric layer disposed on a side of the resonant structure remote from the resonator carrier;
and the upper electrode structure is arranged on one side of the single crystal piezoelectric layer far away from the resonance structure.
10. The bulk acoustic wave resonator according to claim 9, wherein a third conductor is connected to the resonating structure and the single crystal piezoelectric layer, the third conductor being exposed outside the single crystal piezoelectric layer.
11. A filter comprising a bulk acoustic wave resonator according to any one of claims 8 to 10.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111457537.7A CN113872549B (en) | 2021-12-02 | 2021-12-02 | Method for manufacturing bulk acoustic wave resonator, bulk acoustic wave resonator and filter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111457537.7A CN113872549B (en) | 2021-12-02 | 2021-12-02 | Method for manufacturing bulk acoustic wave resonator, bulk acoustic wave resonator and filter |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113872549A CN113872549A (en) | 2021-12-31 |
| CN113872549B true CN113872549B (en) | 2022-03-01 |
Family
ID=78985552
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111457537.7A Active CN113872549B (en) | 2021-12-02 | 2021-12-02 | Method for manufacturing bulk acoustic wave resonator, bulk acoustic wave resonator and filter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113872549B (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107342748A (en) * | 2017-07-04 | 2017-11-10 | 浙江大学 | A kind of bulk acoustic wave resonator of based single crystal piezoelectric membrane and preparation method thereof |
| CN111130484A (en) * | 2019-07-25 | 2020-05-08 | 珠海晶讯聚震科技有限公司 | Encapsulated electronic assembly |
| CN113572448A (en) * | 2021-09-23 | 2021-10-29 | 深圳新声半导体有限公司 | Bulk acoustic wave resonator |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10630259B2 (en) * | 2018-02-05 | 2020-04-21 | Zhuhai Crystal Resonance Technologies Co., Ltd. | Single crystal piezoelectric RF resonators and filters with improved cavity definition |
| US20200313648A1 (en) * | 2019-03-28 | 2020-10-01 | Global Communication Semiconductors, Llc | Single-Crystal Bulk Acoustic Wave Resonator and Method of Making Thereof |
-
2021
- 2021-12-02 CN CN202111457537.7A patent/CN113872549B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107342748A (en) * | 2017-07-04 | 2017-11-10 | 浙江大学 | A kind of bulk acoustic wave resonator of based single crystal piezoelectric membrane and preparation method thereof |
| CN111130484A (en) * | 2019-07-25 | 2020-05-08 | 珠海晶讯聚震科技有限公司 | Encapsulated electronic assembly |
| CN113572448A (en) * | 2021-09-23 | 2021-10-29 | 深圳新声半导体有限公司 | Bulk acoustic wave resonator |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113872549A (en) | 2021-12-31 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7275292B2 (en) | Method for fabricating an acoustical resonator on a substrate | |
| US7355324B2 (en) | Silicon film bulk acoustic wave device and process of the same | |
| JP4113637B2 (en) | Acoustic resonator and manufacturing method | |
| CN108365829A (en) | The preparation method of monocrystalline piezoelectric rf-resonator and filter | |
| EP1187318A2 (en) | Acoustic resonator | |
| US11817839B2 (en) | Single-crystal bulk acoustic wave resonator and method of making thereof | |
| US20230291376A1 (en) | Piezoelectric acoustic resonator manufactured with piezoelectric thin film transfer process | |
| CN113572446A (en) | Method for manufacturing bulk acoustic wave resonator, bulk acoustic wave resonator and filter | |
| JP2007028669A (en) | Method of manufacturing thin-film acoustic resonator | |
| US7489067B2 (en) | Component with a piezoelectric functional layer | |
| US20220103147A1 (en) | Lithium niobate or lithium tantalate fbar structure and fabricating method thereof | |
| CN110719082B (en) | Acoustic wave resonator package | |
| CN105262456A (en) | High-performance FBAR (thin-film bulk acoustic resonator) and manufacturing method thereof | |
| US20200358423A1 (en) | Piezoelectric film cavity structure for a bulk acoustic wave (baw) resonator and method therefor | |
| US11646710B2 (en) | Piezoelectric acoustic resonator manufactured with piezoelectric thin film transfer process | |
| CN113572444B (en) | Method for manufacturing bulk acoustic wave resonator | |
| CN116318029B (en) | Bulk acoustic wave resonator and method for manufacturing the same | |
| CN113708740A (en) | Piezoelectric film bulk acoustic resonator and preparation method thereof | |
| KR20210113557A (en) | Acoustic wave device and manufacturing method for the same | |
| JP2002372974A (en) | Thin-film acoustic resonator and method of manufacturing the same | |
| CN113872549B (en) | Method for manufacturing bulk acoustic wave resonator, bulk acoustic wave resonator and filter | |
| CN115001429B (en) | Preparation method of filter | |
| US11533039B2 (en) | Lithium niobate or lithium tantalate FBAR structure and fabricating method thereof | |
| CN113098417B (en) | Preparation method of filter and filter | |
| CN117040463B (en) | Preparation method and structure of filter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |