Vibration element and manufacturing method thereof

Abstract

PURPOSE: To provide a vibrating element and a manufacturing method thereof which are able to reduce cracks at cutting edges, thereby improving reliability.SOLUTION: The manufacturing method of the vibrating element includes the following steps. A quartz wafer is provided which has a first surface and a second surface opposite to the first surface. A first etching process is performed on the quartz wafer to form multiple inverted mesa portions, where the inverted mesa portions have a first thickness. The quartz wafer is singulated to form multiple vibrating elements. Each of the vibrating elements includes one of the inverted mesa portions. A second etching process is performed on the vibrating elements to form chamfers at edges of the vibrating elements.SELECTED DRAWING: Figure 1L

Description

[Technical Field]

[0001] The present invention relates to a chip and a method for manufacturing the same, and more particularly to a vibrating element and a method for manufacturing the same. [Background technology]

[0002] A quartz crystal oscillator is an electronic component that generates vibration frequencies, and with the trend toward lighter, thinner, and smaller electronic products, the size of quartz crystal units is constantly shrinking. However, during the cutting process of quartz crystal units, cracks of over 5 micrometers are likely to occur at the cutting edge, making the quartz crystal unit susceptible to breakage when external force is applied, which affects the reliability of the quartz crystal unit. Summary of the Invention [Problem to be solved by the invention]

[0003] Improving the reliability of quartz crystal units is currently a challenge to be solved. The present invention provides a vibrating element and a manufacturing method thereof that can reduce cracks on the cutting edge and improve reliability. [Means for solving the problem]

[0004] The method for manufacturing a vibrating piece of the present invention includes the following steps: providing a quartz crystal wafer; the quartz crystal wafer having a first surface and a second surface opposite the first surface; performing a first etching process on the quartz crystal wafer to form a plurality of inverted mesa portions; the plurality of inverted mesa portions having a first thickness; singulating the quartz crystal wafer to form a plurality of vibrating pieces; each of the plurality of vibrating pieces including one of the plurality of inverted mesa portions; performing a second etching process on the plurality of vibrating pieces to form chamfered structures on the edges of the plurality of vibrating pieces.

[0005] In one embodiment of the present invention, the second etching step mentioned above is an isotropic etching step.

[0006] In one embodiment of the present invention, after the second etching step is performed on the above-described plurality of vibrator elements, the plurality of reverse mesa portions have a third thickness, and the third thickness is smaller than the first thickness.

[0007] In one embodiment of the present invention, the ratio of the third thickness to the first thickness is less than 0.9.

[0008] In one embodiment of the present invention, the step of performing the first etching process on the above-mentioned quartz crystal wafer includes the following steps: forming a first recess in a first surface of the quartz crystal wafer; forming a second recess in a second surface of the quartz crystal wafer; the first recess corresponding to the second recess.

[0009] In one embodiment of the present invention, the above-described manufacturing method further includes forming a mask layer on the first and second surfaces of the quartz crystal wafer. The mask layer includes a plurality of openings, and the positions of the plurality of openings define the positions of the plurality of inverted mesas. The step of performing a first etching process on the quartz crystal wafer includes immersing the quartz crystal wafer in an etching solution to remove portions of the quartz crystal wafer that are not covered by the mask layer.

[0010] In one embodiment of the present invention, the step of forming the plurality of openings in the mask layer described above includes the steps of forming a patterned photoresist layer on the mask layer, using the patterned photoresist layer as a mask to remove the mask layer not covered by the patterned photoresist layer to form the plurality of openings and expose the first and second surfaces of a portion of the quartz wafer, and removing the patterned photoresist layer.

[0011] In one embodiment of the present invention, the step of singulating the above-mentioned quartz crystal wafer includes using a laser to define a dividing groove in the quartz crystal wafer, and using wet etching to divide the quartz crystal wafer along the dividing groove into multiple vibrating bars.

[0012] The resonator element of the present invention includes an inverted mesa portion and a peripheral portion. The peripheral portion laterally surrounds the inverted mesa portion, and the thickness of the inverted mesa portion is smaller than the thickness of the peripheral portion. At least one chamfered structure is provided between the top or bottom surface of the peripheral portion and the outer side surface.

[0013] In one embodiment of the present invention, the included angle between the at least one chamfered structure and the top surface or the bottom surface is between 95 degrees and 125 degrees.

[0014] In one embodiment of the present invention, the edge of the aforementioned periphery has a notch.

[0015] In one embodiment of the present invention, the depth of the notch mentioned above is less than 4 micrometers.

[0016] In one embodiment of the present invention, the at least one chamfer structure includes a first chamfer structure and a second chamfer structure, which are respectively located on opposite sides of the peripheral portion of the reverse mesa portion, wherein the first chamfer structure is an inclined surface connecting the bottom surface and the outer surface of the peripheral portion, and the second chamfer structure is an inclined surface connecting the top surface and the outer surface of the peripheral portion. [Effects of the Invention]

[0017] As described above, the vibrating piece of the present invention forms an inverted mesa portion through two etching processes, thereby forming an inverted mesa portion having a predetermined thickness and modifying the edge of the vibrating piece, thereby reducing the occurrence of cracks and the possibility of breakage due to external impact, thereby improving its reliability. [Brief explanation of the drawings]

[0018] [Figure 1A] 1A to 1C are cross-sectional views of a method for manufacturing a vibrator element according to an embodiment of the present invention. [Figure 1B] 1A to 1C are cross-sectional views of a method for manufacturing a vibrator element according to an embodiment of the present invention. [Figure 1C] 1A to 1C are cross-sectional views of a method for manufacturing a vibrator element according to an embodiment of the present invention. [Figure 1D] 1A to 1C are cross-sectional views of a method for manufacturing a vibrator element according to an embodiment of the present invention. [Figure 1E] 1A to 1C are cross-sectional views of a method for manufacturing a vibrator element according to an embodiment of the present invention. [Figure 1F] 1A to 1C are cross-sectional views of a method for manufacturing a vibrator element according to an embodiment of the present invention. [Figure 1G] 1A to 1C are cross-sectional views of a method for manufacturing a vibrator element according to an embodiment of the present invention. [Figure 1H] 1A to 1C are cross-sectional views of a method for manufacturing a vibrator element according to an embodiment of the present invention. [Figure 1I] 1A to 1C are cross-sectional views of a method for manufacturing a vibrator element according to an embodiment of the present invention. [Figure 1J] 1A to 1C are cross-sectional views of a method for manufacturing a vibrator element according to an embodiment of the present invention. [Figure 1K] 1A to 1C are cross-sectional views of a method for manufacturing a vibrator element according to an embodiment of the present invention. [Figure 1L] 1A to 1C are cross-sectional views of a method for manufacturing a vibrator element according to an embodiment of the present invention. [Figure 2] FIG. 1B is a plan view of the vibrator element of FIG. 1L. [Figure 3] 1 is a cross-sectional view of a sealing structure according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0019]

[0023] Hereinafter, exemplary embodiments of the present invention will be fully described with reference to the drawings, but the present invention should not be limited to the embodiments described herein because it can be implemented in many different ways. In the drawings, for clarity, the size and thickness of each region, part, and layer may not be drawn to scale.

[0020] Directional terms referred to herein, such as "upper," "lower," "front," "rear," "left," "right," etc., refer to the directions in the accompanying drawings, and therefore, the directional terms used are for illustrative purposes only and are not intended to limit the present invention.

[0021] In the following embodiments, the same or similar components are designated by the same or similar reference numerals, and the description thereof will be omitted. In addition, the features of different embodiments can be combined with each other if there is no contradiction, and simple equivalent changes and modifications based on the present specification or claims shall all be included in the scope of this patent.

[0022] It should be understood that, although terms such as "first," "second," and "third" may be used herein to describe various components, parts, regions, layers, and / or portions, these components, parts, regions, layers, and / or portions should not be limited by these terms. These terms are used to distinguish one component, part, region, layer, or portion from another component, part, region, layer, or portion. Thus, a first component, part, region, layer, or portion discussed below could be referred to as a second component, part, region, layer, or portion without departing from the teachings of the present text.

[0023] 1A to 1L are cross-sectional views of a method for manufacturing a vibrator element according to one embodiment of the present invention.

[0024] 1A, a quartz crystal wafer 100 is provided. The quartz crystal wafer 100 has a first surface 100a and a second surface 100b opposite the first surface 100a. In some embodiments, the quartz crystal wafer 100 may have a single crystal structure.

[0025] Next, a mask layer 110 is formed on the first surface 100a and the second surface 100b of the quartz wafer 100. In some embodiments, the mask layer 110 includes a metallic material, such as gold, chromium, nickel, copper, or other suitable metallic material. In some embodiments, the mask layer 110 can be formed by chemical vapor deposition, physical vapor deposition, or other suitable method.

[0026] 1B, a photoresist layer 120 is formed on the mask layer 110. In some embodiments, the photoresist layer 120 can be formed by spin coating, chemical vapor deposition, physical vapor deposition, or other suitable method.

[0027] 1C, using a photomask (not shown) as a mask, the photoresist layer 120 is exposed and developed to form a patterned photoresist layer 120′, which can define an inverted mesa portion IM that is subsequently etched.

[0028] 1D, the patterned photoresist layer 120′ is used as a mask to remove the mask layer 110 that is not covered by the patterned photoresist layer 120′, thereby forming a plurality of openings OP and exposing the first surface 100a and the second surface 100b of a portion of the quartz wafer 100. For example, wet etching can be used to remove the mask layer 110 that is not covered by the patterned photoresist layer 120′ by immersing the resulting structure in an etching solution that has high etching selectivity with respect to the mask layer 110. However, the present invention is not limited thereto, and other suitable methods may be used to remove the mask layer 110 that is not covered by the patterned photoresist layer 120′.

[0029] 1E, the patterned photoresist layer 120' is removed. In some embodiments, the patterned photoresist layer 120' can be removed by an ashing process, a wet etching process, a dry etching process, a chemical mechanical polishing process, or other suitable method.

[0030] Referring to FIG. 1F, a first etching process is performed on the quartz crystal wafer 100 using the mask layer 110 as a mask to form multiple inverted mesas 102. The unetched portion of the quartz crystal wafer 100 is also referred to as the peripheral portion 104. The inverted mesas 102 have a first thickness H1, and the peripheral portion 104 has a second thickness H2, where the first thickness H1 is smaller than the second thickness H2. In some embodiments, the ratio of the first thickness H1 to the second thickness H2 is between approximately 0.45 and 0.65.

[0031] In some embodiments, the first etching step is a wet etching step. For example, the quartz wafer 100 is immersed in an etching solution to selectively remove portions of the quartz wafer 100 not covered by the mask layer 110, thereby forming a first recess R1 on the first surface 100a of the quartz wafer 100 within the inverted mesa portion IM and a second recess R2 on the second surface 100b of the quartz wafer 100. The first recess R1 and the second recess R2 correspond to each other. In some embodiments, the depth of the first recess R1 is approximately the same as the depth of the second recess R2, but the present invention is not limited to this. In some embodiments, the etching solution used in the first etching step may have high etching selectivity for the quartz wafer 100.

[0032] In some embodiments, the quartz crystal wafer 100 has a relatively fast etching rate in the crystal lattice growth direction, so that portions of the quartz crystal wafer 100 underneath the mask layer 110 are also etched. For example, in FIG. 1F, the left side of the first recess R1 extends below the mask layer 110, so the left and right sides of the first recess R1 are asymmetric. Meanwhile, the right side of the second recess R2 extends below the mask layer 110, so the left and right sides of the second recess R2 are asymmetric. In some embodiments, the bottom surface and sidewall of the first recess R1 form included angles φ1 and φ2, which are different angles. For example, the angle of the included angle φ1 is larger than the angle of the included angle φ2. In some embodiments, the bottom surface and sidewall of the second recess R2 form included angles φ3 and φ4, which are different angles. For example, the included angle φ4 is greater than the included angle φ3.

[0033] After the first etching process is performed on the crystal wafer 100, the inverted mesa portion 102 is first formed. At this time, the inverted mesa portion 102 does not have the predetermined thickness that the final vibrating piece is intended to achieve. The first thickness H1 of the inverted mesa portion 102 may be between 1.1 and 1.5 times the predetermined thickness of the vibrating piece.

[0034] 1G, the mask layer 110 is removed. In some embodiments, the mask layer 110 can be removed by a wet etching process, a dry etching process, a chemical mechanical polishing process, or other suitable method.

[0035] Referring to FIGS. 1H and 1I, a crystal wafer 100 is singulated to form multiple vibrating pieces 100A. Each of the multiple vibrating pieces 100A includes one of the multiple inverted mesas 102. Specifically, in FIG. 1H, a laser 200 is used to define a dividing groove 100' in the crystal wafer 100. The crystal wafer 100 can be divided into multiple vibrating pieces 100A along the dividing groove 100'. The path scanned by the laser 200 on the crystal wafer 100 is the path of the dividing groove 100'. Because the laser 200 has high energy, it can alter the properties of the laser-treated crystal wafer 100 (i.e., the dividing groove 100'). For example, it can change the structure to a twin crystal structure, making the properties of the dividing groove 100' different from those of a crystal wafer 100 that has not been laser-treated.

[0036] 1I, the dividing grooves 100' are selectively etched using wet etching to divide the crystal wafer 100 into multiple vibrating bars 100A along the dividing grooves 100'. Because the properties of the dividing grooves 100' differ from those of a crystal wafer 100 that has not been laser-treated, an etching solution with an appropriate etching selectivity can be selected to etch the dividing grooves 100', thereby dividing the crystal wafer 100 into multiple vibrating bars 100A. For example, this etching solution can include amine hydrofluoride or other suitable etching solution.

[0037] 1J, the frequency of the inverted mesa portion 102 of the vibrating piece 100A is measured, and the time required for the subsequent etching process to reach a predetermined frequency is calculated. For example, the frequency of the inverted mesa portion 102 of the vibrating piece 100A is measured using the space charge measurement system 210, and then, based on the difference between the measured frequency and the desired frequency, the time required for the subsequent etching process to obtain the inverted mesa portion 102 having a predetermined thickness can be calculated.

[0038] 1K and 1L, a second etching process is performed on the resonator element 100A to etch the inverted mesa portion 102 to a predetermined thickness and form a chamfered structure 106 on the edge of the resonator element 100A to modify the edge of the resonator element 100A and reduce the occurrence of cracks. In FIG. 1K, for clarity, the outline of the resonator element 100A before the second etching process is shown by a dashed line, and the outline of the resonator element 100A after the second etching process is shown by a solid line.

[0039] In some embodiments, the second etching process is an isotropic etching process, such as a wet etching process. Therefore, all surfaces of the vibrating element 100A are etched, forming the inverted mesa portion 102 having the third thickness H3 and the peripheral portion 104 having the fourth thickness H4. Here, the third thickness H3 is smaller than the first thickness H1, and the fourth thickness H4 is smaller than the second thickness H2. In some embodiments, the ratio of the third thickness H3 to the first thickness H1 is smaller than 0.9 or smaller than 0.88. In some embodiments, the ratio of the third thickness H3 to the first thickness H1 is between 0.8 and 0.9. In this way, the vibrating element 100A can achieve an edge modification effect through the second etching process, and at the same time, the predetermined thickness of the inverted mesa portion 102 can be achieved.

[0040] In some embodiments, the vibrating piece 100A has a relatively fast etching rate in its crystal lattice growth direction, so that the edge of the vibrating piece 100A can easily form the chamfered structure 106 in the crystal lattice growth direction, and the first recess R1 and the second recess R2 are etched more in the crystal lattice growth direction. For example, in FIG. 1L, the peripheral portion 104 includes a first portion 1041 and a second portion 1042, which are located on opposite sides of the inverted mesa portion 102. The first recess R1 is etched more in the direction of the first portion 1041 (compared to the direction of the second portion 1042), and the second recess R2 is etched more in the direction of the second portion 1042 (compared to the direction of the first portion 1041). Therefore, the left and right sides of the first recess R1 are asymmetric with each other, and the left and right sides of the second recess R2 are also asymmetric with each other. Meanwhile, the vibrating element 100A includes two chamfered structures (e.g., a first chamfered structure 106a and a second chamfered structure 106b), which are located between the bottom surface 104b and the outer surface 104c of the first portion 1041 of the peripheral portion 104 and between the top surface 104a and the outer surface 104c of the second portion 1042, respectively. In some embodiments, there is no chamfered structure between the top surface 104a and the outer surface 104c of the first portion 1041 of the peripheral portion 104, and there is no chamfered structure between the bottom surface 104b and the outer surface 104c of the second portion 1042 of the peripheral portion 104. That is, the top surface 104a and the outer surface 104c of the first portion 1041 of the peripheral portion 104 are essentially perpendicular to each other, and the bottom surface 104b and the outer surface 104c of the second portion 1042 of the peripheral portion 104 are also essentially perpendicular to each other. However, the present invention is not limited to this, and in other embodiments, there may be a chamfered structure between the top surface 104a and the outer surface 104c of the first portion 1041 of the peripheral portion 104, and between the bottom surface 104b and the outer surface 104c of the second portion 1042 of the peripheral portion 104.

[0041] Based on the above, the manufacture of the resonator element 100A of this embodiment is nearly complete. The inverted mesa portion 102 of the resonator element 100A is formed by two etching processes. The first etching process forms the inverted mesa portion 102, and then the second etching process modifies the edges of the resonator element 100A. At the same time, the inverted mesa portion 102 is etched to the required thickness. This reduces the occurrence of cracks and thereby improves the reliability of the resonator element 100A.

[0042] Fig. 2 is a top view of the vibrator element of Fig. 1L. Fig. 1L may be a cross-sectional view taken along line A-A' in Fig. 2. Specifically, Fig. 1L is a cross-sectional view taken along the short side direction D1 of the vibrator element 100A.

[0043] 1L and 2, the vibrator element 100A includes an inverted mesa portion 102 and a peripheral portion 104. The peripheral portion 104 laterally surrounds the inverted mesa portion 102, and the thickness of the inverted mesa portion 102 (i.e., the third thickness H3) is smaller than the thickness of the peripheral portion (i.e., the fourth thickness H4). The peripheral portion 104 has at least one chamfered structure 106 between the top surface 104a or the bottom surface 104b and the outer surface 104c.

[0044] In some embodiments, the thickness of the inverted mesa portion 102 (i.e., the third thickness H3) is between 5 micrometers and 20 micrometers, but the present invention is not limited thereto, and the thickness of the inverted mesa portion 102 can be adjusted according to actual needs.

[0045] The peripheral portion 104 may include a first portion 1041, a second portion 1042, a third portion 1043, and a fourth portion 1044, each connected to the periphery of the reverse mesa portion 102. The first portion 1041 faces the second portion 1042, and the third portion 1043 faces the fourth portion 1044. For example, in FIG. 2 , the first portion 1041 is located on the left side of the reverse mesa portion 102, the second portion 1042 is located on the right side of the reverse mesa portion 102, the third portion 1043 is located on the upper side of the reverse mesa portion 102, and the fourth portion 1044 is located on the lower side of the reverse mesa portion 102. In some embodiments, the width of the fourth portion 1044 is wider than the widths of the first portion 1041, the second portion 1042, and the third portion 1043, and functions as a connection portion with other components in a subsequent package structure. (The width of first portion 1041 refers to the distance between the edge of first portion 1041 and the edge of inverted mesa portion 102 closest to first portion 1041 when viewed from a plan view; the width of second portion 1042 refers to the distance between the edge of second portion 1042 and the edge of inverted mesa portion 102 closest to second portion 1042 when viewed from a plan view; the width of third portion 1043 refers to the distance between the edge of third portion 1043 and the edge of inverted mesa portion 102 closest to third portion 1043 when viewed from a plan view; and the width of fourth portion 1044 refers to the distance between the edge of fourth portion 1044 and the edge of inverted mesa portion 102 closest to fourth portion 1044 when viewed from a plan view.)

[0046] In some embodiments, the chamfered structure 106 is, for example, an inclined surface connected to the top surface 104a or the bottom surface 104b and the outer surface 104c of the peripheral portion 104. Specifically, in FIG. 1L, the vibrating element 100A includes two chamfered structures (e.g., a first chamfered structure 106a and a second chamfered structure 106b) located on opposite sides of the peripheral portion 104 (e.g., the first portion 1041 and the second portion 1042) of the inverted mesa portion 102. The first chamfered structure 106a is, for example, an inclined surface connecting the bottom surface 104b of the first portion 1041 of the peripheral portion 104 and the outer surface 104c, and the first chamfered structure 106a and the bottom surface 104b of the first portion 1041 form an included angle θ1. The second chamfered structure 106b is, for example, an inclined surface connecting the top surface 104a and the outer surface 104c of the second portion 1042 of the peripheral portion 104, and the second chamfered structure 106b and the top surface 104a of the second portion 1042 have an included angle θ2. In some embodiments, the included angles θ1 and θ2 may each be between 95 degrees and 125 degrees. In this way, the possibility of cracks occurring on the edge of the vibrating element 100A can be reduced.

[0047] In some embodiments, the top surface 104a and the outer surface 104c of the first portion 1041 have an included angle θ3, and the included angle θ1 is essentially greater than the included angle θ3. The bottom surface 104b and the outer surface 104c of the second portion 1042 have an included angle θ4, and the included angle θ2 is essentially greater than the included angle θ4.

[0048] In some embodiments, the top surface 104a and the outer surface 104c of the first portion 1041 are connected essentially perpendicularly, and the bottom surface 104b and the outer surface 104c of the second portion 1042 are connected essentially perpendicularly. In some embodiments, the included angle θ3 and the included angle θ4 may each be between 85 degrees and 115 degrees, although the present invention is not limited thereto.

[0049] In some embodiments, after the above manufacturing process, as shown in FIG. 1L, the bottom surface and sidewall of the first recess R1 form opposing included angles φ1' and φ2' in the short-side direction D1, where the included angle φ1' is larger than the included angle φ2'. The bottom surface and sidewall of the second recess R2 form opposing included angles φ3' and φ4' in the short-side direction D1, where the included angle φ4' is larger than the included angle φ3'. In some embodiments, the included angles φ1' and φ4' may each be between 140 degrees and 170 degrees, although the present invention is not limited thereto. In some embodiments, the included angles φ2' and φ3' may each be between 92 degrees and 112 degrees, although the present invention is not limited thereto. In some embodiments, the included angles φ′ and φ′ are located on opposite sides of the inverted mesa portion 102 and face each other, while the included angles φ′ and φ′ are located on opposite sides of the inverted mesa portion 102 and face each other.

[0050] In some embodiments, the third portion 1043 and the fourth portion 1044 of the peripheral portion 104 essentially do not have a chamfered structure (see the cross-sectional view of FIG. 3 ). That is, the top surface 104a and the bottom surface 104b of the third portion 1043 and the fourth portion 1044 are essentially vertically connected to the outer surface 104c, respectively, but the present invention is not limited thereto.

[0051] In some embodiments, as shown in FIG. 2 , the edge L1 of the first portion 1041 and / or the edge L2 of the second portion 1042 of the peripheral portion 104 may have a notch v. In some embodiments, the depth h of the notch v is less than 4 micrometers. Therefore, even if the vibrating element 100A is subjected to an external force, the stress can be within the allowable range, reducing the possibility of breakage. In this specification, the depth h of the notch v refers to the vertical distance between the tip of the notch v and the edge where the notch v is located. While FIG. 2 exemplarily shows only one notch v on the edge L2 of the second portion 1042, this is not intended to limit the present invention. The edge L1 of the first portion 1041 and the edge L2 of the second portion 1042 may each have one or more notches v.

[0052] FIG. 3 shows a cross-sectional view of a package structure according to one embodiment of the present invention. It should be noted that the embodiment of FIG. 3 incorporates the component symbols and some of the content of the embodiment of FIG. 1L. The same or similar component symbols are used to indicate the same or similar components, and descriptions of the same technical content will be omitted. The omitted parts can be described in the above-mentioned embodiments, so they will not be repeated here. The vibrator element 100A shown in FIG. 3 is a cross-sectional view taken along line B-B' in FIG. 2. That is, the vibrator element 100A shown in FIG. 3 is a cross-sectional view taken along the long side direction D2 of the vibrator element 100A. (The long side direction D2 and the short side direction D1 are perpendicular to each other.)

[0053] Referring to FIG. 3, the package structure 10 includes a vibrating element 100A, a first electrode 130, a second electrode 140, a base 150, and a top cover 160. The vibrating element 100A may be the vibrating element 100A of FIG. 1L. The relevant details can be found in the above description, and will not be described again here. The first electrode 130 and the second electrode 140 may be disposed on opposite sides of the inverted mesa portion 102 of the vibrating element 100A. For example, the first electrode 130 is located on the top surface of the inverted mesa portion 102, and the second electrode 140 is located on the bottom surface of the inverted mesa portion 102. The region of the inverted mesa portion 102 between the first electrode 130 and the second electrode 140 is a vibration region, and the thickness of the inverted mesa portion 102 determines the vibration frequency of the vibration region. In some embodiments, the first electrode 130 and the second electrode 140 can extend to the periphery 104 of the vibrating piece 100A along the top and bottom surfaces of the inverted mesa portion 102, respectively. In some embodiments, the vibrating piece 100A, the first electrode 130, and the second electrode 140 can form a resonator or an oscillator.

[0054] The base 150 has an accommodating space 152, allowing the vibrating element 100A to be placed within the accommodating space 152. The top cover 160 is placed on the base 150 and covers the vibrating element 100A, sealing the accommodating space 152. In some embodiments, the packaging structure 10 further includes a seal ring or an adhesive layer 170 to seal the top cover 160 and the base 150. In some embodiments, the fourth portion 1044 of the peripheral portion 104 of the vibrating element 100A can be adhered to the base 150 via an adhesive 180. That is, the first portion 1041, the second portion 1042, and the third portion 1043 of the peripheral portion 104 of the vibrating element 100A are essentially suspended in air. The adhesive 180 is, for example, a conductive adhesive, and connects the first electrode 130 and the second electrode 140 to corresponding pads (not shown) or circuits (not shown) within the base 150.

[0055] The package structure 10 represents one application method for the vibrating element 100A. By reducing cracks on the edge of the vibrating element 100A, the possibility of breakage due to external impact can be reduced, thereby improving the reliability of the package structure 10.

[0056] As described above, the vibrating piece of the present invention has an inverted mesa portion formed by two etching processes. This allows the inverted mesa portion to be formed to a predetermined thickness while modifying the edge of the vibrating piece, thereby reducing the occurrence of cracks and the possibility of breakage due to external impact, thereby improving its reliability.

[0057] Although the present invention has been disclosed by the above embodiments, these do not limit the present invention, and those skilled in the art can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention is defined by the following claims. [Industrial Applicability]

[0058] The vibrating element and its manufacturing method are suitable for related applications in resonators or oscillators. [Explanation of symbols]

[0059] 10 Package Structure 100 quartz wafers 100' split groove 100a First surface 100b 2nd surface 100A vibrating piece 102 Reverse Mesa 104 Periphery 104a Top surface 104b bottom 104c External surface 106 Chamfered structure 106a First chamfer structure 106b Second chamfer structure 110 Mask Layer 120 photoresist layer 120' patterned photoresist layer 130 1st electrode 140 2nd electrode 150 base 152 Containment Space 160 Top lid 170 Seal ring or adhesive layer 200 Laser 210 Space Charge Measurement System 1041 Part 1 1042 Part 2 1043 Part 3 1044 Part 4 h depth v notch A-A', B-B' lines H1 First thickness H2 Second thickness H3 Third thickness H4 4th thickness IM Inverted mesa part L1, L2 edges OP Opening R1 First recess R2 Second recess θ1, θ2, θ3, θ4, φ1, φ2, φ3, φ4, φ1’, φ2’, φ3’, φ4’ Included angles

Claims

1. providing a quartz crystal wafer, the quartz crystal wafer having a first surface and a second surface opposite the first surface; performing a first etching process on the quartz crystal wafer to form a plurality of inverted mesa portions, the plurality of inverted mesa portions having a first thickness, the first thickness being 1.1 to 1.5 times a predetermined thickness; singulating the crystal wafer to form a plurality of vibrating pieces, each of the plurality of vibrating pieces including one of the plurality of inverted mesa portions and a peripheral portion laterally surrounding the inverted mesa portion, the thickness of the inverted mesa portion being smaller than the thickness of the peripheral portion, the peripheral portion including first and second portions extending along a long side direction and third and fourth portions extending along a short side direction, the first and second portions being located on opposite sides of the inverted mesa portion in the short side direction, the third and fourth portions being located on opposite sides of the inverted mesa portion in the long side direction, and the long side direction and the short side direction being perpendicular; performing a second etching process on the plurality of vibrating bars to etch the inverted mesa portion to the predetermined thickness and form chamfers on the edges of the plurality of vibrating bars; Including, the chamfer includes a first chamfer structure located on the first portion of the periphery, the first chamfer structure being an inclined surface connecting the bottom surface and the outer surface of the periphery; the first chamfered structure and the bottom surface of the first portion form an included angle θ1, the top surface of the first portion and the outer surface form an included angle θ3, and the included angle θ1 is greater than the included angle θ3; the third portion and the fourth portion do not have a chamfered structure; A method for manufacturing a vibrator element, wherein the width of the first portion provided with the first chamfered structure is smaller than the width of the fourth portion not having the chamfered structure.

2. The method for manufacturing a vibrator element according to claim 1 , wherein the second etching step is an isotropic etching step.

3. 2. The method for manufacturing a vibrator element according to claim 1, wherein after the second etching process is performed on the plurality of vibrator elements, the plurality of inverted mesa portions have a third thickness, and the third thickness is smaller than the first thickness.

4. The method for manufacturing a vibrator element according to claim 3 , wherein a ratio of the third thickness to the first thickness is smaller than 0.

9.

5. The step of performing the first etching process on the quartz crystal wafer includes: forming a first recess in the first surface of the quartz crystal wafer; forming a second recess in the second surface of the quartz crystal wafer; The method for manufacturing a vibrator element according to claim 1 , further comprising:

6. forming a mask layer on the first surface and the second surface of the quartz crystal wafer, the mask layer including a plurality of openings, the positions of the plurality of openings defining the positions of the plurality of reverse mesas; The step of performing the first etching process on the quartz crystal wafer includes: The method for manufacturing a vibrator element according to claim 1 , further comprising the step of immersing the quartz crystal wafer in an etching solution to remove the portion of the quartz crystal wafer that is not covered by the mask layer.

7. forming the plurality of openings in the mask layer, forming a patterned photoresist layer on the mask layer; using the patterned photoresist layer as a mask, removing the mask layer that is not covered by the patterned photoresist layer to form the plurality of openings and expose the first surface and the second surface of a portion of the quartz crystal wafer; removing the patterned photoresist layer; The method for manufacturing a vibrator element according to claim 6 , further comprising:

8. the step of singulating the quartz crystal wafer comprises: defining parting grooves in the quartz crystal wafer using a laser; Dividing the crystal wafer into the plurality of vibrating bars along the dividing grooves using wet etching; The method for manufacturing a vibrator element according to claim 1 , comprising:

9. an inverted mesa portion; The surrounding area and the peripheral portion laterally surrounds the inverted mesa portion, and the thickness of the inverted mesa portion is smaller than the thickness of the peripheral portion; the peripheral portion includes a first portion and a second portion extending along a long side direction and a third portion and a fourth portion extending along a short side direction, the first portion and the second portion being located on opposite sides of the reverse mesa portion in the short side direction, the third portion and the fourth portion being located on opposite sides of the reverse mesa portion in the long side direction, and the long side direction and the short side direction being perpendicular to each other; At least one chamfered structure is provided between the top surface or bottom surface of the peripheral portion and the outer surface, and the at least one chamfered structure is a first chamfer structure located on the first portion of the peripheral portion, the first chamfer structure being an inclined surface connecting the bottom surface and the outer surface of the peripheral portion; the first chamfered structure and the bottom surface of the first portion form an included angle θ1, the top surface of the first portion and the outer surface form an included angle θ3, and the included angle θ1 is greater than the included angle θ3; the third portion and the fourth portion do not have a chamfered structure; The width of the first portion where the first chamfered structure is provided is smaller than the width of the fourth portion where no chamfered structure is provided.

10. The vibrator element according to claim 9 , wherein an included angle between the at least one chamfered structure and the top surface or the bottom surface is between 95 degrees and 125 degrees.

11. The at least one chamfer structure further comprises: a second chamfered structure located on the second portion of the inverted mesa portion, the second chamfered structure being an inclined surface connecting the top surface and the outer surface of the peripheral portion; The resonator element according to claim 9 , wherein the width of the second portion provided with the second chamfered structure is smaller than the width of the fourth portion not having the chamfered structure.

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