Vibration Device

Abstract

To provide a vibration device that has an excellent mechanical strength.SOLUTION: A vibration device has: a vibration element; a package that has a base having a first surface and a second surface in a front and back relationship and having the vibration element arranged on the first surface, an oscillation circuit arranged on the base and electrically connected with the vibration element, and a lid being a semiconductor substrate joined to the base to accommodate the vibration element and in electrical conduction with the base; and a resin layer that is arranged on an outer face of the package.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a vibration device. [Background technology]

[0002] The piezoelectric vibrator described in Patent Document 1 includes a concave package, a piezoelectric vibrating piece bonded to the bottom of the package, and a lid member that hermetically seals the package. The package and the lid member are bonded by, for example, surface activated bonding. The package and the lid member are made of, for example, a silicon substrate, and an oscillation circuit and the like are formed on the surface of the silicon substrate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-081415 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the piezoelectric vibrator of Patent Document 1, the package and the lid member are made of a silicon substrate, which causes a problem that the package is more fragile than, for example, a ceramic package and is more susceptible to damage due to impact such as being dropped. [Means for solving the problem]

[0005] The vibration device of the present invention comprises a vibration element and a package including: a base which is a semiconductor substrate having a first surface and a second surface which are in a front-back relationship, the vibration element being disposed on the first surface side; an oscillator circuit which is disposed on the base and electrically connected to the vibration element; and a lid which is a semiconductor substrate which is joined to the base so as to accommodate the vibration element and is electrically connected to the base; and a resin layer disposed on the outer surface of the package. [Brief description of the drawings]

[0006] [Figure 1] 3 is a cross-sectional view showing the vibration device according to the first embodiment, taken along line AA in FIG. 2. [Diagram 2] FIG. 2 is a plan view showing the upper surface of the base. [Diagram 3] 1A to 1C are process diagrams showing a manufacturing process of a vibration device. [Figure 4] 1A to 1C are cross-sectional views illustrating a method for manufacturing a vibration device. [Diagram 5] 1A to 1C are cross-sectional views illustrating a method for manufacturing a vibration device. [Figure 6] 1A to 1C are cross-sectional views illustrating a method for manufacturing a vibration device. [Figure 7] 1A to 1C are cross-sectional views illustrating a method for manufacturing a vibration device. [Figure 8] 1A to 1C are cross-sectional views illustrating a method for manufacturing a vibration device. [Figure 9] 1A to 1C are cross-sectional views illustrating a method for manufacturing a vibration device. [Figure 10] 1A to 1C are cross-sectional views illustrating a method for manufacturing a vibration device. [Figure 11] 1A to 1C are cross-sectional views illustrating a method for manufacturing a vibration device. [Figure 12] 1A to 1C are cross-sectional views illustrating a method for manufacturing a vibration device. [Figure 13] 1A to 1C are cross-sectional views illustrating a method for manufacturing a vibration device. [Figure 14] 1A to 1C are cross-sectional views illustrating a method for manufacturing a vibration device. [Figure 15] FIG. 4 is a cross-sectional view showing a vibration device according to a second embodiment. [Figure 16] 1A to 1C are process diagrams showing a manufacturing process of a vibration device. [Figure 17] 1A to 1C are cross-sectional views illustrating a method for manufacturing a vibration device. [Figure 18] 1A to 1C are cross-sectional views illustrating a method for manufacturing a vibration device. [Figure 19] 1A to 1C are cross-sectional views illustrating a method for manufacturing a vibration device. [Figure 20] FIG. 11 is a cross-sectional view showing a vibration device according to a third embodiment. [Figure 21] FIG. 11 is a cross-sectional view showing a vibration device according to a fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] Hereinafter, preferred embodiments of the vibration device will be described with reference to the accompanying drawings. For ease of explanation, the upper side in Fig. 1, Fig. 4 to Fig. 15, and Fig. 17 to Fig. 21 will be referred to as "upper" and the lower side as "lower". In this case, in Fig. 2, the front side of the paper is "upper" and the back side is lower.

[0008] First Embodiment Fig. 1 is a cross-sectional view showing a vibration device according to a first embodiment, and is a cross-sectional view taken along line AA in Fig. 2. Fig. 2 is a plan view showing the upper surface of a base. Fig. 3 is a process diagram showing a manufacturing process of the vibration device. Figs. 4 to 14 are cross-sectional views for explaining the manufacturing method of the vibration device.

[0009] 1 includes a package 10 having an airtight housing portion S, a vibration element 4 housed in the housing portion S, and a resin layer 9 disposed on a portion of the outer surface of the package 10. The package 10 also includes a base 2 to which the vibration element 4 is bonded via a pair of metal bumps 81, 82, and a lid 3 that covers the vibration element 4 and is bonded to an upper surface 2a of the base 2. An integrated circuit 6 including an oscillation circuit 6A that causes the vibration element 4 to oscillate is formed on the lower surface 2b side of the base 2.

[0010] The base 2 is a silicon substrate. In this embodiment, a P-type silicon substrate is used in particular. Therefore, when the resonator device 1 is used, the base 2 is connected to the ground, which is a constant potential. However, the base 2 is not particularly limited, and may be an N-type silicon substrate. In addition, a semiconductor substrate other than silicon, such as a semiconductor substrate of Ge, GaP, GaAs, InP, etc., may be used.

[0011] The base 2 is plate-shaped and has an upper surface 2a as a first surface and a lower surface 2b as a second surface, which are opposite surfaces. The base 2 also has a step 27 in the middle of the thickness direction, and the portion on the upper surface 2a side of the step 27 is smaller in diameter than the portion on the lower surface 2b side. In the following, the side surface above the step 27 will be referred to as side surface 2c1, and the side surface below the step 27 will be referred to as side surface 2c2.

[0012] An insulating film 26 is formed on the upper surface 2a and the lower surface 2b of the base 2. The insulating film 26 is, for example, a silicon oxide film formed by thermally oxidizing the surface of the base 2. However, the insulating film 26 is not particularly limited, and may be, for example, a silicon nitride film. The method for forming the insulating film 26 is not limited to thermal oxidation, and may be, for example, CVD (Chemical Vapor Deposition).

[0013] In addition, an integrated circuit 6 electrically connected to the vibration element 4 is formed on the lower surface 2b of the base 2. By forming the integrated circuit 6 on the base 2 in this manner, the base 2 can be effectively utilized. In particular, by forming the integrated circuit 6 on the lower surface 2b, a larger space can be secured for forming the integrated circuit 6 since there is no bonding area with the lid 3, compared to the case where the integrated circuit 6 is formed on the upper surface 2a as in the second embodiment described later.

[0014] The integrated circuit 6 includes an oscillator circuit 6A that is electrically connected to the vibration element 4 and oscillates the vibration element 4 to generate an oscillation signal such as a clock signal. The integrated circuit 6 may include circuits other than the oscillator circuit 6A. Examples of such circuits include a processing circuit that processes an output signal from the oscillator circuit 6A, and examples of such processing circuits include a PLL circuit.

[0015] A laminate 60 is formed on the lower surface 2b, which is formed by laminating a wiring layer 62, an insulating layer 63, a passivation film 64, and a terminal layer 65. A plurality of active elements (not shown) formed on the lower surface 2b are electrically connected via wiring included in the wiring layer 62 to form an integrated circuit 6. The terminal layer 65 has a plurality of mounting terminals 650 electrically connected to the integrated circuit 6. In the resonator device 1, the integrated circuit 6 is connected to an external device via the mounting terminals 650.

[0016] In the illustrated configuration, the laminate 60 includes one wiring layer 62, but is not limited thereto, and a plurality of wiring layers 62 may be laminated with insulating layers 63 interposed therebetween. In other words, the wiring layers 62 and the insulating layers 63 may be alternately laminated a plurality of times. This can increase the degree of freedom in routing the wiring within the integrated circuit 6 and in installing a plurality of mounting terminals 650, for example.

[0017] The base 2 is also formed with a pair of through holes 21, 22 penetrating the base 2 in the thickness direction. A conductive material such as a metal material is filled in each of the through holes 21, 22, and through electrodes 210, 220 are formed. A pair of wirings 28, 29 electrically connected to the vibration element 4 are also disposed on the upper surface 2a of the base 2. The wiring 28 is electrically connected to the integrated circuit 6 via the through electrode 210, and the wiring 29 is electrically connected to the integrated circuit 6 via the through electrode 220.

[0018] The lid 3 is a silicon substrate, like the base 2. This makes the linear expansion coefficients of the base 2 and the lid 3 equal, suppressing the generation of thermal stress caused by thermal expansion, and resulting in a resonator device 1 with excellent vibration characteristics. In addition, since the resonator device 1 can be formed by a semiconductor process, the resonator device 1 can be manufactured with high precision and can be made compact. However, the lid 3 is not particularly limited, and a semiconductor substrate other than silicon, such as a semiconductor substrate of Ge, GaP, GaAs, InP, etc., may be used.

[0019] 1, the lid 3 is box-shaped and has an upper surface 3a, a lower surface 3b, and a bottomed recess 31 that opens to the lower surface 3b and accommodates the vibration element 4 therein. In addition, in a plan view, the lid 3 is slightly smaller than the base 2, and the side surface 3c is flush with the side surface 2c1 of the base 2 above the step 27.

[0020] The lid 3 has its lower surface 3b joined to the upper surface 2a of the base 2 via a metal layer 7. By joining the base 2 and the lid 3 via the metal layer 7, they can be joined firmly and tightly. This increases the strength of the package 10 and also increases the airtightness of the housing portion S. A specific joining method will be described later in the explanation of the manufacturing method.

[0021] The lid 3 is electrically connected to the base 2 via the metal layer 7. As described above, when the resonator device 1 is in use, the base 2 is connected to the ground, and the lid 3 is also connected to the ground. Therefore, the entire package 10 functions as a shield, and the influence of external electromagnetic noise can be reduced. This results in a highly reliable resonator device 1.

[0022] In addition, in a plan view of the package 10, the outer edge of the metal layer 7 is located inside the outer edge of the upper surface 2a of the base 2 and the outer edge of the lower surface 3b of the lid 3. Therefore, on the outside of the metal layer 7, a concave gap G is formed between the upper surface 2a of the base 2 and the lower surface 3b of the lid 3 and facing the outside of the package 10. With this configuration, the metal layer 7 can be protected from dicing performed during the manufacture of the vibration device 1. Therefore, it is possible to effectively suppress a decrease in the bonding strength and a destruction of the airtightness of the housing portion S. This point will be described later in the manufacturing method of the vibration device 1.

[0023] The housing section S in the package 10 is airtight and in a reduced pressure state, preferably in a state closer to a vacuum. This reduces viscous resistance and improves the oscillation characteristics of the vibration element 4. However, the atmosphere in the housing section S is not particularly limited, and may be, for example, an atmosphere filled with an inert gas such as nitrogen or Ar, or may be in an atmospheric pressure state or a pressurized state instead of a reduced pressure state.

[0024] As shown in FIG. 2, the vibration element 4 has a vibration substrate 41 and an electrode 42 arranged on the surface of the vibration substrate 41. The vibration substrate 41 has a thickness shear vibration mode, and is formed of an AT-cut quartz substrate in this embodiment. The AT-cut quartz substrate has a third-order frequency-temperature characteristic, and therefore the vibration element 4 has excellent temperature characteristics. The electrode 42 has an excitation electrode 421 arranged on the upper surface, and an excitation electrode 422 arranged on the lower surface opposite the excitation electrode 421. The electrode 42 has a pair of terminals 423 and 424 arranged on the lower surface of the vibration substrate 41, a wiring 425 that electrically connects the terminal 423 and the excitation electrode 421, and a wiring 426 that electrically connects the terminal 424 and the excitation electrode 422.

[0025] The configuration of the vibration element 4 is not limited to the above-mentioned configuration. For example, the vibration element 4 may be a mesa type in which the vibration region sandwiched between the excitation electrodes 421 and 422 protrudes from its surroundings, or conversely, may be an inverted mesa type in which the vibration region is recessed from its surroundings. In addition, bevel processing for grinding the periphery of the vibration substrate 41, or convex processing for making the upper and lower surfaces into convex curved surfaces may be performed.

[0026] The vibration element 4 is not limited to vibrating in a thickness-shear vibration mode, and may be, for example, a tuning fork type vibration element with multiple vibrating arms that perform bending vibration in an in-plane direction. In other words, the vibration substrate 41 is not limited to being formed from an AT-cut quartz substrate, and may be formed from a quartz substrate other than an AT-cut quartz substrate, for example, an X-cut quartz substrate, a Y-cut quartz substrate, a Z-cut quartz substrate, a BT-cut quartz substrate, an SC-cut quartz substrate, an ST-cut quartz substrate, or the like.

[0027] The material of the vibration substrate 41 is not limited to quartz crystal, and may be, for example, a piezoelectric single crystal such as lithium niobate, lithium tantalate, lithium tetraborate, langasite, potassium niobate, or gallium phosphate, or may be a piezoelectric single crystal other than these. Furthermore, the vibration element 4 is not limited to a piezoelectric drive type vibration piece, and may be an electrostatic drive type vibration piece using electrostatic force.

[0028] As shown in Fig. 2, the vibration element 4 is bonded to the upper surface 2a of the base 2 via a pair of metal bumps 81, 82, and is electrically connected to the wirings 28, 29. The metal bumps 81, 82 are, for example, stud bumps, plated bumps, etc. The metal bumps 81, 82 are bonded to the wirings 28, 29 by ultrasonic bonding, and are bonded to the terminals 423, 424 by thermocompression bonding. However, the bonding method is not particularly limited. Also, a conductive adhesive may be used as a bonding member instead of the metal bumps 81, 82.

[0029] As shown in FIG. 1, the resin layer 9 is disposed on the outer surface of the package 10. Specifically, the resin layer 9 covers the entire area of ​​the portion above the step 27 formed on the base 2 of the package 10. That is, the resin layer 9 covers the step 27 and the side surface 2c1 of the base 2, the joint between the base 2 and the lid 3, and the entire lid 3. In this way, by disposing the resin layer 9 on the outer surface of the package 10, the resin layer 9 can absorb and reduce external forces such as impacts when dropped and stresses applied when picked up, making the package 10 less susceptible to external forces. Therefore, damage to the package 10, particularly cracks and chips, can be effectively suppressed, resulting in a vibration device 1 with excellent mechanical strength.

[0030] The effect of protecting against impact is particularly noticeable by covering the corners of the package 10 with the resin layer 9. In this embodiment, the corners between the top surface 3a and the side surfaces 3c of the lid 3 and the corners between the side surfaces 3c are covered with the resin layer 9. In addition, the effect of protecting against stress during pick-up is particularly noticeable by covering the side surfaces of the package 10 with the resin layer 9.

[0031] Furthermore, by disposing the resin layer 9 on the outer surface of the package 10, the coefficient of friction of the surface of the vibration device 1 is increased compared to when the package 10 is exposed, making the vibration device 1 less slippery and easier to pick up.

[0032] Moreover, the resin layer 9 covers the joint between the lid 3 and the base 2 and fills the gap G. This makes it possible to protect the joint. Also, the joint strength between the lid 3 and the base 2 can be further increased, and the airtightness of the storage section S can be increased. Furthermore, this portion acts as an anchor, making it difficult for the resin layer 9 to peel off from the package 10. Such a resin layer 9 has insulating properties. Therefore, electrical conduction with the package 10 can be avoided, and electrostatic damage to the integrated circuit 6 due to electrical shock such as static electricity from the outside can be suppressed. As a result, a highly reliable resonator device 1 is obtained.

[0033] In addition, the side surface 9c of the resin layer 9 is flush with the side surface 2c2 below the step 27 of the base 2. Therefore, the resin layer 9 is less likely to get caught on an external structure, and curling of the resin layer 9 can be effectively suppressed.

[0034] The resin layer 9 is not particularly limited, but examples thereof include epoxy resin, phenol resin, urea resin, melamine resin, polyester (unsaturated polyester) resin, polyimide resin, silicone resin, polyurethane resin, etc., and one or more of these may be mixed to be used. This makes it possible to obtain a resin layer 9 with excellent heat resistance.

[0035] The configuration of the vibration device 1 has been described above. Next, a manufacturing method of the vibration device 1 will be described. As shown in Fig. 3, the manufacturing process of the vibration device 1 includes a preparation step S11, a placement step S12, a bonding step S13, a groove formation step S14, a resin layer formation step S15, and a singulation step S16. Each of these steps S11 to S16 will be described in detail below.

[0036] [Preparation process S11] First, as shown in FIG. 4, a base wafer 20 is prepared that includes an upper surface 20a and a lower surface 20b that are in a reverse relationship and includes a plurality of singulation regions Q, i.e., a portion that will become the base 2. The base wafer 20 is a base material of the base 2 and is a silicon substrate. Next, as shown in FIG. 5, an integrated circuit 6 is formed on the lower surface 20b side of the base wafer 20 for each singulation region Q. Next, as shown in FIG. 6, through holes 21 and 22 that reach the integrated circuit 6 from the upper surface side of the base wafer 20 are formed for each singulation region Q. Next, as shown in FIG. 7, through electrodes 210 and 220, wirings 28 and 29, and a first metal layer 71 are formed for each singulation region Q. In this way, by forming the integrated circuit 6 on the base wafer 20, the base wafer 20 can be effectively utilized.

[0037] [Placement process S12] 8, the vibration element 4 is arranged on the upper surface 20a side of the base wafer 20 for each individual region Q. Specifically, the vibration element 4 is prepared, and the vibration element 4 is bonded to the upper surface 20a via metal bumps 81 and 82. In addition, the wiring 28 and the terminal 423 of the vibration element 4 are electrically connected via the metal bump 81, and the wiring 29 and the terminal 424 are electrically connected via the metal bump 82. This electrically connects the vibration element 4 and the integrated circuit 6.

[0038] [Joining process S13] 9, a lid wafer 30 including a plurality of singulation regions Q, i.e., portions that will become the lids 3, is prepared. In the lid wafer 30, a recess 31 that opens to the lower surface 30b and a second metal layer 72 disposed on the lower surface 30b so as to surround the recess 31 are formed for each singulation region Q. The first and second metal layers 71 and 72 may be configured, for example, by laminating a surface layer of gold (Au) on a base layer of copper (Cu).

[0039] Next, as shown in FIG. 10, the surfaces of the first and second metal layers 71, 72 are irradiated with an ion beam or plasma to activate the surfaces of the first and second metal layers 71, 72, and the metals of the first and second metal layers 71, 72 are diffused to bond the base wafer 20 and the lid wafer 30. The metal layer 7 is formed by such diffusion between the first and second metal layers 71, 72. This results in a device wafer 100 in which a housing portion S that houses a vibration element 4 is formed for each individualized region Q. In the device wafer 100, the base wafer 20 and the lid wafer 30 are electrically connected via the metal layer 7.

[0040] According to such a bonding method, the base wafer 20 and the lid wafer 30 can be bonded more firmly and tightly, and the mechanical strength and airtightness of the vibration device 1 can be increased. In addition, since the base 2 and the lid 3 can be bonded at room temperature (a temperature lower than the melting points of the first and second metal layers 71 and 72), internal stress is unlikely to remain in the package 10, and thermal damage to the vibration element 4 is also reduced.

[0041] 11, a dicing tape DT is prepared as a holding member, and the dicing tape DT is attached to the lower surface 20b side of the device wafer 100. This results in the dicing tape DT holding the device wafer 100 from the lower surface 20b side.

[0042] [Groove formation process S14] As shown in FIG. 12, a first groove 110 is formed from the lid wafer 30 side at the boundary between adjacent singulation regions Q. The first groove 110 is a bottomed groove that opens to the upper surface 30a of the lid wafer 30 and does not penetrate to the lower surface 20b of the base wafer 20. The first groove 110 reaches the lower surface 20b side of the bonding portion between the base wafer 20 and the lid wafer 30, that is, halfway through the base wafer 20. Therefore, the bonding portion between the base wafer 20 and the lid wafer 30 faces the first groove 110. The lid wafer 30 is singulated for each singulation region Q, and a lid 3 is formed in each singulation region Q.

[0043] The method for forming the first grooves 110 is not particularly limited, but in this embodiment, they are formed by half dicing from the upper surface 30a side of the lid wafer 30 using a dicing blade DB1. This makes it possible to easily form the first grooves 110. In addition, since minute irregularities are formed on the surface of the first grooves 110, that is, the surface becomes rough, the adhesion between the package 10 and the resin layer 9 is improved.

[0044] Here, in a plan view of the device wafer 100, the outer edge of the metal layer 7 is located inside the outer edge of the singulation region Q. Therefore, when the first groove 110 is formed with the dicing blade DB1, contact between the dicing blade DB1 and the metal layer 7 is avoided, and clogging of the dicing blade DB1 can be suppressed. Therefore, a decrease in the processing accuracy of the first groove 110 is suppressed. In addition, damage to the metal layer 7 can be suppressed, and a decrease in the bonding strength between the base wafer 20 and the lid wafer 30, a decrease in the airtightness of the accommodation section S, a break in airtightness, etc. can be effectively suppressed.

[0045] [Resin layer forming process S15] As shown in FIG. 13, a resin material is disposed on the surface of the device wafer 100 to form a resin layer 9. The resin layer 9 is formed on the upper surface 30a of the lid wafer 30 and in the first groove 110. The resin layer 9 is also filled in the gap G facing the first groove 110. By filling the gap G with the resin layer 9, the bonded portion between the base wafer 20 and the lid wafer 30 can be protected. In addition, the bond strength between the base wafer 20 and the lid wafer 30 can be further increased, and the airtightness of the storage section S can also be increased. In addition, this portion serves as an anchor, making it difficult for the resin layer 9 to peel off from the device wafer 100. The resin layer 9 can be formed by, for example, spin coating, spray coating, or the like.

[0046] Here, by making the first groove 110 have a bottom, the device wafer 100 is not singulated but remains connected via the base wafer 20. Therefore, the device wafer 100 has sufficient rigidity to resist stress caused by shrinkage during hardening of the resin layer 9, and warping or bending of the device wafer 100 caused by the stress can be effectively suppressed. Therefore, warping of the device wafer 100 caused by the stress is suppressed, and the next singulation step S16 can be performed more accurately and smoothly.

[0047] [Singulation process S16] As shown in FIG. 14, a second groove 120 is formed at the boundary between adjacent singulation regions Q, penetrating the device wafer 100, and the device wafer 100 is singulated for each singulation region Q. As a result, a plurality of vibration devices 1 are formed at once. Although the method of forming the second groove 120 is not particularly limited, in this embodiment, the second groove 120 is formed by dicing from the lid wafer 30 side using a dicing blade DB2. As a result, the second groove 120 can be easily formed. In particular, by performing dicing from the lid wafer 30 side, cutting of the dicing tape DT by the dicing blade DB2 can be avoided, and all the singulated vibration devices 1 are held by the dicing tape DT. As a result, the plurality of vibration devices 1 can be prevented from coming apart.

[0048] Note that the dicing blade DB2 is thinner than the dicing blade DB1, and the width W2 of the second groove 120 is narrower than the width W1 of the first groove 110. That is, W2 < W1. Therefore, as shown in FIG. 14, even after singulation, the resin layer 9 remains on the side surface of each package 10, and the vibration device 1 in which the entire upper portion from the step 27 is covered with the resin layer 9 can be obtained.

[0049] As described above, the vibration device 1 has been described. Such a vibration device 1 has, as described above, a vibration element 4, an upper surface 2a which is a first surface in a front-back relationship, and a lower surface 2b which is a second surface, and the vibration element 4 is disposed on the upper surface 2a side. A package 10 having a base 2 which is a semiconductor substrate, an oscillation circuit 6A disposed on the base 2 and electrically connected to the vibration element 4, and a lid 3 which is a semiconductor substrate bonded to the base 2 so as to accommodate the vibration element 4 and electrically connected to the base 2; And a resin layer 9 disposed on the outer surface of the package 10. Thus, by disposing the resin layer 9 on the outer surface of the package 10, external forces such as impact during dropping and stress applied during pickup are absorbed and relaxed by the resin layer 9, and the package 10 becomes less likely to receive external forces. Therefore, breakage of the package 10, particularly cracks and chips, can be effectively suppressed, and the vibration device 1 having excellent mechanical strength can be obtained. Further, compared with the case where the package 10 is exposed, the friction coefficient of the surface of the vibration device 1 is increased, so that the vibration device 1 is difficult to slip and is easy to pick up.

[0050] Further, as described above, the resin layer 9 is disposed so as to cover the corner portions of the package 10. Thereby, the effect of protecting from impact becomes more remarkable.

[0051] Further, as described above, the resin layer 9 has insulating properties. Therefore, conduction with the lid 3 and the base 2 can be avoided, and electrostatic breakdown of the integrated circuit 6 due to an electrical impact such as static electricity from the outside can be suppressed. As a result, a highly reliable vibration device 1 can be obtained.

[0052] As described above, the base 2 and the lid 3 are connected to a constant potential. This allows the base 2 and the lid 3 to function as a shield and reduce the influence of external electromagnetic noise. This results in a highly reliable resonator device 1.

[0053] As described above, the resin layer 9 covers the joint between the base 2 and the lid 3. This makes it possible to protect the joint.

[0054] As described above, the base 2 and the lid 3 are joined via the metal layer 7. This allows them to be joined firmly and tightly. As a result, the strength of the vibration device 1 can be increased, and the airtightness of the storage section S can be increased.

[0055] As described above, in plan view, the outer edge of the metal layer 7 is located inside the outer edges of the base 2 and the lid 3, and the resin layer 9 is disposed in the gap G between the base 2 and the lid 3 formed by the metal layer 7. This can further increase the bonding strength between the lid 3 and the base 2, and can also increase the airtightness of the storage section S. In addition, this portion acts as an anchor, making it difficult for the resin layer 9 to peel off from the lid 3 and the base 2.

[0056] As described above, the oscillator circuit 6A is disposed on the lower surface 2b side of the base 2. By forming the integrated circuit 6 on the lower surface 2b side in this manner, a larger space for forming the integrated circuit 6 can be secured since there is no bonding area with the lid 3, compared to the case where the integrated circuit 6 is formed on the upper surface 2a side as in the fourth embodiment described later.

[0057] <Second embodiment> Fig. 15 is a cross-sectional view showing a vibration device according to a second embodiment. Fig. 16 is a process diagram showing a manufacturing process of the vibration device. Fig. 17 to Fig. 19 are cross-sectional views for explaining the manufacturing method of the vibration device.

[0058] This embodiment is similar to the first embodiment described above, except that the shape of the base 2 and the arrangement of the resin layer 9 are different. In the following description, the present embodiment will be described focusing on the differences from the previous embodiment, and the description of the similarities will be omitted. In addition, in Figs. 15 to 19, the same reference numerals are used for the same configurations as the previous embodiment.

[0059] 15, in the resonation device 1 of this embodiment, no step 27 is formed on the side surface of the base 2, and the entire side surface is covered with the resin layer 9. In other words, the resin layer 9 is disposed on the entire outer surface of the package 10 except for the lower surface. With this configuration, a larger portion is covered with the resin layer 9 compared to the first embodiment described above, and therefore the function of the resin layer 9 becomes more prominent.

[0060] Next, a method for manufacturing the vibration device 1 will be described. As shown in Fig. 16, the manufacturing process of the vibration device 1 includes a preparation step S21, a placement step S22, a bonding step S23, a groove forming step S24, a resin layer forming step S25, and a singulation step S26. Each of these steps S21 to S26 will be described in detail below, but steps up to the bonding step S23 are similar to the bonding step S13 in the first embodiment described above. Therefore, the following description will begin with the groove forming step S24.

[0061] [Groove formation process S24] 17, the device wafer 100 held on the dicing tape DT is diced from the lid wafer 30 side, and a first groove 110 penetrating the device wafer 100 is formed at the boundary between adjacent singulation regions Q. As a result, the device wafer 100 is singulated for each singulation region Q, and a plurality of devices 1A are obtained. The devices 1A are vibration devices 1 on which no resin layer 9 is formed.

[0062] The method for forming the first grooves 110 is not particularly limited, but in this embodiment, the first grooves 110 are formed by dicing from the lid wafer 30 side using a dicing blade DB1. This makes it possible to easily form the first grooves 110. By performing dicing from the lid wafer 30 side, it is possible to avoid cutting the dicing tape DT by the dicing blade DB1, and the individual devices 1A are held by the dicing tape DT. This makes it possible to prevent the devices 1A from being broken into pieces.

[0063] [Resin layer forming step S25] As shown in FIG. 18, a resin layer 9 is formed on the surface of each device 1A. This results in a vibration device 1. In this embodiment, the resin layer 9 is formed on the upper surface 3a of each lid 3 and in the first groove 110. That is, the resin layer 9 is formed so as to cover the upper surface and side surfaces of the package 10. The resin layer 9 is not particularly limited, and can be formed by, for example, spin coating, spray coating, or the like.

[0064] [Singulation process S26] 18, adjacent resonator devices 1 are integrated with each other by the resin layer 9 formed in the first groove 110. Therefore, in this process, as shown in FIG. 19, a second groove 120 penetrating the device wafer 100 (resin layer 9) is formed at the boundary between adjacent singulation regions Q to singulate the resonator devices 1.

[0065] Although the method for forming the second grooves 120 is not particularly limited, in this embodiment, the second grooves 120 are formed by dicing from the lid wafer 30 side using a dicing blade DB2. This makes it possible to easily form the second grooves 120. By performing dicing from the lid wafer 30 side, it is possible to avoid cutting the dicing tape DT by the dicing blade DB2, and the individualized vibration devices 1 are held by the dicing tape DT.

[0066] Note that the dicing blade DB2 is thinner than the dicing blade DB1, and the width W2 of the second groove 120 is narrower than the width W1 of the first groove 110. That is, W2 < W1. Therefore, even after cutting the resin layer 9 in this step, the resin layer 9 remains on the side surfaces of each package 10, and the vibration device 1 in which the entire area except the lower surface of the package 10 is covered with the resin layer 9 can be obtained.

[0067] Also, according to such a second embodiment, the same effects as those of the above-described first embodiment can be exhibited.

[0068] <Third Embodiment> FIG. 20 is a cross-sectional view showing a vibration device according to the third embodiment.

[0069] This embodiment is mainly the same as the above-described first embodiment except that the joining method of the base 2 and the lid 3 is different. In the following description, the differences between this embodiment and the above-described embodiments will be mainly described, and the description of the same matters will be omitted. Also, in FIG. 20, the same components as those in the above-described embodiments are denoted by the same reference numerals.

[0070] As shown in FIG. 20, in the vibration device 1 of this embodiment, the upper surface 2a of the base 2 and the lower surface 3b of the lid 3 are surface-activated and joined. Surface-activated joining is, for example, a joining method in which the upper surface 2a of the base 2 and the lower surface 3b of the lid 3 are each activated by irradiating an ion beam or plasma, and these surfaces are directly joined to each other without using other members, like silicon substrates. According to such a joining method, the lid 3 and the base 2 can be joined more firmly and tightly, the strength of the package 10 can be increased, and the airtight failure of the housing portion S can be effectively suppressed. Also, since no other members are used, for example, compared with the above-described first embodiment, the package 10 can be made thinner, that is, the vibration device 1 can be miniaturized.

[0071] As described above, in the vibration device 1 of the present embodiment, the base 2 and the lid 3 are bonded by surface activation bonding. This allows the lid 3 and the base 2 to be bonded more firmly and tightly, thereby increasing the strength of the vibration device 1 and effectively preventing the airtightness of the storage section S from being broken. In addition, since no other members are used, the vibration device 1 can be made smaller than the first embodiment described above, for example.

[0072] The third embodiment as described above can also achieve the same effects as the first embodiment described above.

[0073] <Fourth embodiment> FIG. 21 is a cross-sectional view showing a vibration device according to a fourth embodiment.

[0074] This embodiment is similar to the first embodiment described above, except for the arrangement of the integrated circuit 6. In the following description, the differences between this embodiment and the previous embodiment will be mainly described, and the description of the similarities will be omitted. In addition, in FIG. 21, the same reference numerals are used for the same configurations as the previous embodiment.

[0075] As shown in FIG. 21, in the resonator device 1 of this embodiment, the integrated circuit 6 including the oscillator circuit 6A is disposed on the upper surface 2a side of the base 2 and is accommodated in the accommodation portion S. With such a configuration, the integrated circuit 6 can be protected from moisture and dust. Therefore, the reliability of the resonator device 1 can be improved. In this embodiment, the resonator element 4 is mounted on the integrated circuit 6, and the terminal layer 65 includes wiring 651, 652 electrically connected to the resonator element 4 via metal bumps 81, 82. In addition, an external terminal 25 electrically connected to the integrated circuit 6 via the through electrodes 210, 220 is disposed on the lower surface 2b side of the base 2.

[0076] As described above, in the resonator device 1 of the present embodiment, the oscillator circuit 6A is disposed on the upper surface 2a side of the base 2. This makes it possible to protect the oscillator circuit 6A from moisture and dust. As a result, it is possible to improve the reliability of the resonator device 1.

[0077] The fourth embodiment as described above can also achieve the same effects as the first embodiment described above.

[0078] Although the vibration device of the present invention has been described above based on the illustrated embodiment, the present invention is not limited thereto, and the configuration of each part can be replaced with any configuration having a similar function. In addition, any other configuration may be added to the present invention. In addition, each embodiment may be appropriately combined.

[0079] In the above-described embodiment, the resin layer 9 is disposed on the top surface and the side surfaces of the package 10, but the arrangement of the resin layer 9 is not particularly limited. For example, the resin layer 9 may be disposed only on the top surface of the package 10, only on the side surfaces, or only on the corners. [Explanation of symbols]

[0080] 1...vibration device, 1A...device, 10...package, 100...device wafer, 110...first groove, 120...second groove, 2...base, 2a...upper surface, 2b...lower surface, 2c1...side surface, 2c2...side surface, 20...base wafer, 20a...upper surface, 20b...lower surface, 21...through hole, 210...through electrode, 22...through hole, 220...through electrode, 25...external terminal, 26... Insulating film, 27...step, 28...wiring, 29...wiring, 3...lid, 3a...upper surface, 3b...lower surface, 3c...side surface, 30...lid wafer, 30a...upper surface, 30b...lower surface, 31...recess, 4...vibration element, 41...vibration substrate, 42...electrode, 421...excitation electrode, 422...excitation electrode, 423...terminal, 424...terminal, 425...wiring, 426...wiring, 6...integrated circuit, 6A...oscillating element Resonance circuit, 60... laminate, 62... wiring layer, 63... insulating layer, 64... passivation film, 65... terminal layer, 650... mounting terminal, 651... wiring, 652... wiring, 7... metal layer, 71... first metal layer, 72... second metal layer, 81... metal bump, 82... metal bump, 9... resin layer, 9c... side, DB1... dicing blade, DB2... dicing blade, DT... dicing tape, G... gap, Q... singulation area, S... accommodation section, S11... preparation step, S12... placement step, S13... bonding step, S14... groove forming step, S15... resin layer forming step, S16... singulation step, S21... preparation step, S22... placement step, S23... bonding step, S24... groove forming step, S25... resin layer forming step, S26... singulation step, W1... width, W2... width

Claims

1. A vibration element; a package including: a base which is a semiconductor substrate having a first surface and a second surface which are opposite surfaces, the vibration element being disposed on the first surface side; an oscillator circuit which is disposed on the base and electrically connected to the vibration element; and a lid which is a semiconductor substrate which is joined to the base so as to accommodate the vibration element and is electrically connected to the base; a resin layer disposed on an outer surface of the package; the base and the lid are bonded to each other via a metal layer; an outer edge of the metal layer is located inside an outer edge of the base and an outer edge of the lid in a plan view, and the resin layer is disposed in a gap between the base and the lid formed by the metal layer; A vibration device characterized in that the side of the resin layer, including the portion corresponding to the gap, is a flat surface.

2. The resonation device according to claim 1 , wherein the resin layer is disposed so as to cover corners of the package.

3. The vibration device according to claim 1 , wherein the resin layer has insulating properties.

4. The vibrating device according to claim 1 , wherein the base and the lid are connected to a constant potential.

5. The vibration device according to claim 1 , wherein the resin layer covers a joint between the base and the lid.

6. The resonator device according to claim 1 , wherein the oscillator circuit is disposed on the second surface side of the base.

7. The resonator device according to claim 1 , wherein the oscillator circuit is disposed on the first surface side of the base.

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