Vibration Device

Abstract

To provide a vibration device that has excellent oscillation characteristics.SOLUTION: A vibration device has: a vibration element; a heat generating unit; a first package that has a first base on which the vibration element and the heat generating unit are arranged, and a first lid joined to the first base to accommodate the vibration element between the first base and the lid; and a low emissivity layer that is arranged on an inner face of the first lid and has a lower emissivity than the emissivity of the first lid. The constituent material of the first lid is silicon. The emissivity at normal temperature of the low emissivity layer is less than 0.5.SELECTED DRAWING: Figure 1

Description

[Technical field]

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

[0002] The vibration device described in Patent Document 1 has a package having a ceramic base with a recess opening on its upper surface and a metal lid joined to the upper surface of the base so as to cover the opening of the recess, and an oscillator circuit, a heating element, and a vibration element housed in the housing space within the package. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-28360 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the vibration device of Patent Document 1, heat in the storage space is easily dissipated to the outside of the package through the metal lid. Therefore, the temperature in the storage space is easily unstable. Therefore, the temperature of the vibration element is not stable, and the oscillation characteristics may be deteriorated. [Means for solving the problem]

[0005] The vibration device of the present invention comprises a vibration element and A heating portion; a first package including a first base in which the vibration element and the heat generating portion are disposed, and a first lid joined to the first base so as to house the vibration element between the first base and a first lid; A low-emissivity layer is disposed on an inner surface of the first lid and has an emissivity lower than that of the first lid.

[0006] A vibration element; A heating portion; a first package including a first base on which the vibration element is disposed and a first lid joined to the first base so as to house the vibration element between the first base and a first lid; a second package including a second base on which the first package is disposed and a second lid joined to the second base so as to accommodate the first package and the heat generating portion between the second base and the second lid; A first low-emissivity layer is disposed on an inner surface of the second lid and has an emissivity lower than that of the second lid. [Brief description of the drawings]

[0007] [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 a vibration element. [Diagram 3] FIG. 4 is a cross-sectional view showing a vibration device according to a second embodiment. [Figure 4] FIG. 11 is a cross-sectional view showing a vibration device according to a third embodiment. [Diagram 5] FIG. 11 is a cross-sectional view showing a vibration device according to a fourth embodiment. [Figure 6] FIG. 13 is a cross-sectional view showing a vibration device according to a fifth embodiment. [Figure 7] FIG. 13 is a cross-sectional view showing a vibration device according to a sixth embodiment. [Figure 8] FIG. 13 is a cross-sectional view showing a vibration device according to a seventh embodiment. [Figure 9] FIG. 13 is a cross-sectional view showing a vibration device according to an eighth embodiment. [Figure 10] 10 is a cross-sectional view showing a modified example of the vibration device in FIG. [Figure 11] 10 is a cross-sectional view showing a modified example of the vibration device in FIG. [Figure 12] FIG. 13 is a cross-sectional view showing a vibration device according to a ninth embodiment. [Figure 13] FIG. 23 is a cross-sectional view showing a vibration device according to a tenth embodiment. [Figure 14] 14 is a cross-sectional view showing a modified example of the vibration device of FIG. 13. [Figure 15] 14 is a cross-sectional view showing a modified example of the vibration device of FIG. 13. [Figure 16] 14 is a cross-sectional view showing a modified example of the vibration device of FIG. 13. [Figure 17] FIG. 21 is a cross-sectional view showing a vibration device according to an eleventh embodiment. [Figure 18] FIG. 23 is a cross-sectional view showing a vibration device according to a twelfth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, preferred embodiments of the vibration device will be described with reference to the accompanying drawings. For ease of explanation, the upper side of each figure, except for Fig. 2, will be referred to as "top" and the lower side as "bottom". In this case, in Fig. 2, the front side of the page is "top" and the back side is "bottom".

[0009] 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 a vibration element.

[0010] The resonator device 1 shown in FIG. 1 is an oscillator, particularly an OCXO (oven-controlled oscillator). The resonator device 1 has a first package 11 having an airtight housing section S therein, and a resonator element 4 housed in the housing section S. The first package 11 also has a first base 2 in which the resonator element 4 is disposed, and a first lid 3 that covers the resonator element 4 and is bonded to an upper surface 2a of the first base 2. A heater 5 is formed as a heat generating section on the upper surface 2a side of the first base 2, and an integrated circuit 6 electrically connected to the resonator element 4 and the heater 5 is formed on the lower surface 2b side of the first base 2.

[0011] The first 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 first base 2 is connected to the ground, which is a constant potential. However, the first 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.

[0012] The first base 2 is plate-shaped and has an upper surface 2a and a lower surface 2b, which are opposite surfaces. An insulating film 20 is formed on each of the upper surface 2a and the lower surface 2b. The insulating film 20 is, for example, a silicon oxide film formed by thermally oxidizing the surface of the first base 2. However, the insulating film 20 is not particularly limited, and may be, for example, a silicon nitride film. The method for forming the insulating film 20 is not limited to thermal oxidation, and may be, for example, CVD (Chemical Vapor Deposition).

[0013] Further, a heater 5 is formed on the upper surface 2a side of the first base 2. The heater 5 has a resistor formed by diffusing impurities such as phosphorus, boron, etc. from the upper surface 2a side of the first base 2. The heater 5 has a function of heating the vibration element 4, and is electrically connected to the integrated circuit 6. In this way, by arranging the heater 5 on the upper surface 2a side of the first base 2, the heater 5 can be arranged in the vicinity of the vibration element 4, and the vibration element 4 can be efficiently heated.

[0014] Moreover, an integrated circuit 6 electrically connected to the vibration element 4 and the heater 5 is formed on the lower surface 2b side of the first base 2. By forming the heater 5 and the integrated circuit 6 on the first base 2 in this manner, the first base 2 can be effectively utilized, and the vibration device 1 can be made smaller.

[0015] The integrated circuit 6 also includes, for example, a temperature sensor 6A, an oscillation circuit 6B, a temperature compensation circuit 6C, and a temperature control circuit 6D. The temperature sensor 6A is a sensor that detects the temperature of the vibration element 4. The oscillation circuit 6B is electrically connected to the vibration element 4, amplifies the output signal of the vibration element 4, and feeds back the amplified signal to the vibration element 4, thereby causing the vibration element 4 to oscillate.

[0016] Furthermore, the temperature compensation circuit 6C performs temperature compensation based on the temperature information output from the temperature sensor 6A so that the frequency fluctuation of the output signal is smaller than the frequency-temperature characteristics of the vibration element 4 itself. The temperature compensation circuit 6C may be, for example, one that adjusts the oscillation frequency of the oscillation circuit 6B by adjusting the capacitance of a variable capacitance circuit connected to the oscillation circuit 6B, or one that adjusts the frequency of the output signal of the oscillation circuit 6B by a PLL circuit or a direct digital synthesizer circuit.

[0017] The temperature control circuit 6D is a circuit for controlling the amount of current flowing through the heater 5 based on the output signal of the temperature sensor 6A, and for maintaining the vibration element 4 at a constant temperature. For example, the temperature control circuit 6D controls the heater 5 so that a desired current flows when the current temperature determined from the output signal of the temperature sensor 6A is lower than a preset reference temperature, and controls the heater 5 so that no current flows when the current temperature is higher than the reference temperature. However, without being limited thereto, the temperature control circuit 6D may control the amount of current flowing through the heater 5 to increase or decrease depending on the difference between the current temperature and the reference temperature.

[0018] A laminate 60 is formed on the lower surface 2b of the first base 2, 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 terminals 650 electrically connected to the integrated circuit 6. In the resonation device 1, the integrated circuit 6 is connected to an external device via the terminals 650.

[0019] 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 terminals 650, for example.

[0020] Further, a pair of through electrodes 21, 22 penetrating the first base 2 in the thickness direction are formed in the first base 2. Further, a pair of wirings 28, 29 electrically connected to the vibration element 4 are arranged on the upper surface 2a of the first base 2. The wirings 28, 29 are electrically connected to the integrated circuit 6 via the through electrodes 21, 22. Similarly, the first base 2 is formed with a through electrode (not shown) penetrating the first base 2 in the thickness direction and electrically connecting the integrated circuit 6 and the heater 5.

[0021] The first lid 3 is a silicon substrate, like the first base 2. This makes the linear expansion coefficients of the first base 2 and the first lid 3 equal, suppressing the generation of thermal stress caused by thermal expansion, and resulting in a vibration device 1 with excellent vibration characteristics. In addition, since the vibration device 1 can be formed by a semiconductor process, the vibration device 1 can be manufactured with high precision and can be made compact. However, the first 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.

[0022] The first lid 3 is box-shaped and has an upper surface 3a, a lower surface 3b, and a bottomed accommodation recess 31 that opens to the lower surface 3b and accommodates the vibration element 4 therein. The lower surface 3b of the first lid 3 is bonded to the upper surface 2a of the first base 2 via a metal layer Q. The metal layer Q is composed of a bonded body of a first metal layer Q1 disposed on the upper surface 2a of the first base 2 and a second metal layer Q2 disposed on the lower surface 3b of the first lid 3. For example, the first base 2 and the first lid 3 are bonded to each other by irradiating the surfaces of the first and second metal layers Q1 and Q2 with an ion beam or plasma to activate the surfaces of the first and second metal layers Q1 and Q2 and diffusing the metals of the first and second metal layers Q1 and Q2. However, the method of bonding the first base 2 and the first lid 3 is not particularly limited.

[0023] Moreover, the first lid 3 is electrically connected to the first base 2 via the metal layer Q. As described above, when the resonator device 1 is in use, the first base 2 is connected to the ground, and therefore the first lid 3 is also connected to the ground. Therefore, the entire first package 11 functions as an electromagnetic shield, and the influence of external electromagnetic noise can be reduced. This results in a highly reliable resonator device 1.

[0024] Moreover, a low-emissivity layer 71 having an emissivity lower than that of the first lid 3 is disposed on the inner surface of the first lid 3, i.e., the surface facing the storage section S. In particular, in this embodiment, the low-emissivity layer 71 is disposed on the bottom surface of the storage recess 31. Therefore, heat (mainly radiant heat from the heater 5) in the storage section S is less likely to escape to the outside of the first package 11 via the first lid 3. Therefore, the inside of the storage section S is heated evenly, the temperature of the vibration element 4 is more stable, and the vibration device 1 can exhibit excellent oscillation characteristics. Furthermore, since the heat in the storage section S is less likely to escape to the outside of the first package 11, the power consumption of the heater 5 is reduced, resulting in a vibration device 1 that can be driven with low power consumption.

[0025] The definition of "emissivity" in this specification is based on JIS Z8117, and this emissivity can be measured, for example, by a spectral emissivity measurement method using an FTIR (Fourier transform infrared spectrophotometer) in accordance with JIS R1801. Since the emissivity of silicon, which is the material constituting the first lid 3, at room temperature is about 0.5, it is sufficient that the emissivity of the low emissivity layer 71 at room temperature is less than 0.5. This makes it difficult for heat to escape from the housing section S, resulting in a resonator device 1 that can be driven with low power consumption and has excellent oscillation characteristics.

[0026] The low emissivity layer 71 may be made of any of the following materials: copper (0.03), titanium (0.08-0.19), tungsten (0.02), aluminum (0.02), aluminum oxide (0.11), gold (0.02), chromium (0.08), nickel (0.05), nickel oxide (0.31-0.46), platinum (0.05), silver (0.06), and cobalt (0.13). The values ​​in parentheses indicate the emissivity of each material. Among these materials, copper, titanium, tungsten, aluminum, aluminum oxide, and gold are materials that are particularly suitable for use in semiconductor processes, and chromium, nickel, nickel oxide, platinum, silver, and cobalt are materials that are particularly suitable for use in sputtering. Therefore, the use of these materials facilitates the manufacture of the resonator device 1.

[0027] The storage section S 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 of the storage 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.

[0028] 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.

[0029] 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.

[0030] 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.

[0031] 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.

[0032] Such a vibration element 4 is bonded to the upper surface 2a of the first base 2 via a pair of conductive bonding members B1 and B2, and is electrically connected to the wirings 28 and 29. However, the bonding method is not particularly limited. For example, one connection may be made with a bonding member, and the other connection may be made with a bonding wire.

[0033] The above describes the vibration device 1. As described above, the vibration device 1 includes a first package 11 having a vibration element 4, a heater 5 as a heat generating part, a first base 2 on which the vibration element 4 and the heater 5 are arranged, a first lid 3 joined to the first base 2 so as to accommodate the vibration element 4 between the first base 2, and a low-emissivity layer 71 arranged on the inner surface of the first lid 3 and having an emissivity lower than that of the first lid 3. This makes it difficult for heat (mainly radiant heat from the heater 5) in the first package 11 to escape to the outside of the first package 11 through the first lid 3. Therefore, the inside of the first package 11 is heated evenly, the temperature of the vibration element 4 is more stable, and the vibration device 1 can exhibit excellent oscillation characteristics. Furthermore, since the heat in the first package 11 is difficult to escape to the outside of the first package 11, the power consumption of the heater 5 is suppressed, and the vibration device 1 can be driven with low power consumption.

[0034] As described above, the first lid 3 is made of silicon, and the emissivity of the low emissivity layer 71 at room temperature is less than 0.5. This makes it difficult for heat inside the first package 11 to escape to the outside of the first package 11 through the first lid 3. This results in an energy-saving resonator device 1 that can exhibit excellent oscillation characteristics.

[0035] As described above, the low emissivity layer 71 is made of a material that contains at least one of copper, titanium, tungsten, aluminum, aluminum oxide, gold, chromium, nickel, nickel oxide, platinum, silver, and cobalt, which makes it easier to manufacture the resonator device 1.

[0036] <Second embodiment> FIG. 3 is a cross-sectional view showing a vibration device according to a second embodiment.

[0037] This embodiment is similar to the first embodiment described above, except for the arrangement of the low-emissivity layer 71. 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 the drawings of this embodiment, the same reference numerals are used for the same configurations as the previous embodiment.

[0038] 3, in the resonator device 1 of this embodiment, a low-emissivity layer 71 is disposed on the bottom and side surfaces of the storage recess 31, in other words, on the entire inner surface of the first lid 3. This makes it even more difficult for heat in the storage section S to escape to the outside of the first package 11 through the first lid 3 than in the first embodiment described above, for example. This results in a resonator device 1 that is more energy efficient and exhibits better oscillation characteristics.

[0039] Furthermore, in this embodiment, the low-emissivity layer 71 is made of the same material as the second metal layer Q2. This allows the low-emissivity layer 71 and the second metal layer Q2 to be formed together, reducing the number of manufacturing steps for the resonator device 1. In particular, in this embodiment, the low-emissivity layer 71 and the second metal layer Q2 are integrally formed, eliminating the need for masking or patterning by etching to separate them. This makes it even easier to manufacture the resonator device 1.

[0040] As described above, the resonator device 1 of the present embodiment has the second metal layer Q2 as a bonding layer that bonds the first lid 3 and the first base 2, and the low-emissivity layer 71 is made of the same material as the second metal layer Q2. This allows the low-emissivity layer 71 and the second metal layer Q2 to be formed at the same time, thereby reducing the number of manufacturing steps for the resonator device 1.

[0041] The second embodiment as described above can also achieve the same effects as the first embodiment described above.

[0042] <Third embodiment> FIG. 4 is a cross-sectional view showing a vibration device according to the third embodiment.

[0043] This embodiment is similar to the first embodiment described above, except for the arrangement of the low-emissivity layer 71. 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 the drawings of this embodiment, the same reference numerals are used for the same configurations as the previous embodiment.

[0044] As shown in Fig. 4, in the resonator device 1 of this embodiment, a low-emissivity layer 71 is also disposed on the outer surface of the first lid 3, i.e., the surface facing the outside of the first package 11. In particular, in this embodiment, the low-emissivity layer 71 is disposed on the upper surface 3a of the first lid 3. This makes it even more difficult for heat in the storage section S to escape to the outside of the first package 11 via the first lid 3 than in the first embodiment described above. This results in a resonator device 1 that is more energy efficient and can exhibit better oscillation characteristics.

[0045] In this embodiment, the low emissivity layer 71 is disposed only on the upper surface 3a of the first lid 3, but the present invention is not limited to this, and for example, the low emissivity layer 71 may also be disposed on the side surface of the first lid 3. In other words, the low emissivity layer 71 may be disposed on the entire outer surface of the first lid 3. This makes the above-mentioned effects more pronounced.

[0046] As described above, in the resonator device 1 of the present embodiment, the low emissivity layer 71 is also disposed on the outer surface of the first lid 3. This makes it more difficult for heat in the housing S to escape to the outside of the first package 11 via the first lid 3. This results in a resonator device 1 that is more energy efficient and exhibits better oscillation characteristics.

[0047] The third embodiment as described above can also achieve the same effects as the first embodiment described above.

[0048] <Fourth embodiment> FIG. 5 is a cross-sectional view showing a vibration device according to a fourth embodiment.

[0049] This embodiment is similar to the first embodiment described above, except that the configuration of the first package 11 is different. 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 the drawings of this embodiment, the same reference numerals are used for the same configurations as the previous embodiment.

[0050] 5, in the resonator device 1 of this embodiment, the first base 2 is made of a ceramic substrate, and the first lid 3 is made of a metal substrate made of Kovar. This results in a first package 11 with high mechanical strength. The integrated circuit 6 and the heater 5 are formed as chips separate from the first base 2 and fixed to the first base 2.

[0051] The first base 2 has a recess 27 that opens on the upper surface 2a, and the first lid 3 is bonded to the upper surface 2a of the first base 2 via a metal layer Q so as to close the opening of the recess 27. The recess 27 has a first recess 271 that opens on the upper surface 2a, a second recess 272 that opens on the bottom surface of the first recess 271 and is smaller than the first recess 271, and a third recess 273 that opens on the bottom surface of the second recess 272 and is smaller than the second recess 272. The integrated circuit 6 is disposed on the bottom surface of the third recess 273, the heater 5 is disposed on the bottom surface of the second recess 272, and the vibration element 4 is disposed on the upper surface of the heater 5. The vibration element 4, the integrated circuit 6, and the heater 5 are electrically connected to each other via the internal wiring 26 and the bonding wire BW formed on the first base 2. Furthermore, a plurality of terminals 23 electrically connected to the integrated circuit 6 are arranged on the lower surface 2b of the first base 2, and the integrated circuit 6 is connected to an external device via these terminals 23.

[0052] In addition, a low-emissivity layer 71 is disposed on the inner surface, i.e., the lower surface 3b, of the first lid 3. Since the emissivity of Kovar, the material of the first lid 3, at room temperature is about 0.05, the emissivity of the low-emissivity layer 71 only needs to be less than 0.05. This makes it difficult for heat in the housing S to escape to the outside of the first package 11, resulting in an energy-saving resonator device 1 with excellent oscillation characteristics.

[0053] The material of the low emissivity layer 71 is not particularly limited, but preferably contains at least one of copper (0.03), tungsten (0.02), aluminum (0.02), and gold (0.02). The numbers in parentheses indicate the emissivity of each material. These materials are easy to use in semiconductor processes, and the use of these materials makes it easy to manufacture the resonator device 1.

[0054] In the above-described resonator device 1, as described above, the constituent material of the first lid 3 is Kovar, and the emissivity of the low emissivity layer 71 at room temperature is less than 0.05. This makes it difficult for heat inside the first package 11 to escape to the outside of the first package 11 through the first lid 3. This results in an energy-saving resonator device 1 that can exhibit excellent oscillation characteristics.

[0055] As described above, the constituent material of the low emissivity layer 71 contains at least one of copper, tungsten, aluminum, and gold, which makes it easier to manufacture the resonator device 1.

[0056] The fourth embodiment can achieve the same effects as the first embodiment. The low emissivity layer 71 can be disposed not only on the inner surface, i.e., the lower surface 3b, of the first lid 3, but also on the outer surface, i.e., the upper surface 3a and the side surfaces.

[0057] <Fifth embodiment> FIG. 6 is a cross-sectional view showing a vibration device according to a fifth embodiment.

[0058] This embodiment is similar to the fourth embodiment described above, except that the configuration of the first package 11 is different. 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 the drawings of this embodiment, the same reference numerals are used for the same configurations as the previous embodiment.

[0059] As shown in Figure 6, in the vibration device 1 of this embodiment, the first base 2 has a recess 27 opening on the upper surface 2a and a recess 25 opening on the lower surface 2b, and the first lid 3 is joined to the upper surface 2a of the first base 2 via a metal layer Q so as to cover the opening of the recess 27.

[0060] The recess 27 has a first recess 271 that opens on the upper surface 2a, and a second recess 272 that opens on the bottom surface of the first recess 271 and is smaller than the first recess 271. The heater 5 is disposed on the bottom surface of the second recess 272, the vibration element 4 is disposed on the bottom surface of the first recess 271, and the integrated circuit 6 is disposed on the bottom surface of the recess 25. The vibration element 4, the integrated circuit 6, and the heater 5 are electrically connected via the internal wiring 26 and the bonding wires BW formed in the first base 2. A plurality of terminals 23 electrically connected to the integrated circuit 6 are disposed on the lower surface 2b of the first base 2, and the integrated circuit 6 is connected to an external device via the terminals 23.

[0061] The fifth embodiment can also achieve the same effects as the first embodiment described above.

[0062] Sixth Embodiment FIG. 7 is a cross-sectional view showing a vibration device according to a sixth embodiment.

[0063] This embodiment is similar to the first embodiment described above, except that it further includes a high-emissivity layer 72. In the following description, the differences between this embodiment and the previous embodiment will be mainly described, and descriptions of similar points will be omitted. In addition, in the drawings of this embodiment, the same reference numerals are used for configurations similar to those of the previous embodiment.

[0064] As shown in Fig. 7, the vibration device 1 of this embodiment further includes a high emissivity layer 72 that is disposed on the upper surface 2a side of the first base 2 in a portion overlapping with the heater 5, and whose upper surface faces the storage section S. The high emissivity layer 72 has a higher emissivity than that of silicon, which is the constituent material of the first base 2. This allows the high emissivity layer 72 to absorb heat from the heater 5 and efficiently release the absorbed heat into the storage section S. Therefore, the vibration element 4 can be quickly heated to a desired temperature, and the time required for the vibration element 4 to reach the desired temperature after activation is short, resulting in a vibration device 1 with good startup characteristics.

[0065] In particular, in this embodiment, the high emissivity layer 72 is disposed only directly above the heater 5, and is not disposed so as to extend around the heater 5 in a plan view, for example. This suppresses the dispersion of heat in the high emissivity layer 72, and the above-mentioned effect becomes more pronounced. However, the arrangement of the high emissivity layer 72 is not particularly limited.

[0066] Since the emissivity of silicon at room temperature is about 0.5, the emissivity of the high emissivity layer 72 at room temperature only needs to be 0.5 or more. This makes it possible to more efficiently release heat from the heater 5 into the housing section S, resulting in a vibration device 1 with better startup characteristics.

[0067] The material constituting such a high emissivity layer 72 preferably contains at least one of copper oxide (0.87), titanium oxide (0.51 to 0.61), silicon oxide (0.65 to 0.9), silicon nitride (0.75 to 0.9), glass material (0.91 to 0.94), aluminum nitride (0.93), and platinum black (0.93). The numbers in parentheses indicate the emissivity of each material.

[0068] Among these, copper oxide, titanium oxide, silicon oxide, silicon nitride, and aluminum nitride are particularly suitable for use in semiconductor processes. In addition, platinum black is suitable for use in sputtering. Therefore, the use of these materials makes it easier to manufacture the resonator device 1.

[0069] Moreover, it is preferable to use metal-based materials such as copper oxide, titanium oxide, aluminum nitride, platinum black, etc., rather than silicon-based materials such as silicon oxide and silicon nitride, as the constituent material of the high-emissivity layer 72. Metal-based materials have higher thermal conductivity than silicon-based materials, and can exhibit a higher heat dissipation effect.

[0070] The sixth embodiment as described above can also achieve the same effects as the first embodiment described above.

[0071] Seventh embodiment FIG. 8 is a cross-sectional view showing a vibration device according to the seventh embodiment.

[0072] This embodiment is similar to the first embodiment described above, except that it has a second package 12 that houses a first package 11. In the following description, the differences between this embodiment and the previous embodiment will be mainly described, and descriptions of similar points will be omitted. In addition, in the drawings of this embodiment, the same reference numerals are used for configurations similar to those of the previous embodiment.

[0073] As shown in FIG. 8, the second package 12 has a second base 8 to which the first package 11 is bonded, and a second lid 9 that covers the first package 11 and is bonded to the upper surface 8a of the second base 8. The second base 8 is made of a ceramic substrate, and the second lid 9 is made of a metal substrate made of Kovar. This provides the second package 12 with high mechanical strength, and can more firmly protect the first package 11 housed therein. Furthermore, the double package structure makes it difficult for the heat of the heater 5 to escape from the vibration device 1, resulting in an energy-saving vibration device 1 with excellent oscillation characteristics. Note that the housing section SS in the second package 12 is preferably in a reduced pressure state, preferably close to a vacuum state. This enhances the heat insulation of the second package 12, and the above-mentioned effects become more pronounced.

[0074] The second base 8 has a recess 87 that opens to the upper surface 8a, and the second lid 9 is joined to the upper surface 8a of the second base 8 via a metal layer Q3 so as to cover the opening of the recess 87. The recess 87 has a first recess 871 that opens to the upper surface 8a, and a second recess 872 that opens to the bottom surface of the first recess 871 and is smaller than the first recess 871. A plurality of terminals 88 are arranged on the bottom surface of the second recess 872, and a plurality of terminals 89 that are electrically connected to the terminals 88 are arranged on the lower surface 8b of the second base 8.

[0075] The first package 11 is disposed on the bottom surface of the second recess 872. The first package 11 is fixed to the bottom surface of the second recess 872 via a conductive bonding member B3 with the first base 2 facing the bottom surface of the second recess 872. The terminal 650 and the terminal 88 are electrically connected to each other via the bonding member B3.

[0076] As described above, the vibration device 1 of the present embodiment has the second package 12 including the second base 8 on which the first package 11 is disposed, and the second lid 9 joined to the second base 8 so as to house the first package 11 between the second base 8. This provides the second package 12 with high mechanical strength, and can more firmly protect the first package 11 housed therein. Furthermore, the double package structure makes it more difficult for the heat of the heater 5 to escape from the vibration device 1, resulting in an energy-saving vibration device 1 with excellent oscillation characteristics.

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

[0078] Eighth embodiment Fig. 9 is a cross-sectional view showing a vibration device according to an eighth embodiment, Fig. 10 and Fig. 11 are cross-sectional views showing modified examples of the vibration device of Fig. 9, respectively.

[0079] This embodiment is the same as the seventh embodiment described above, except that the arrangement of the low-emissivity layer is 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 each drawing of this embodiment, the same reference numerals are used for the same configurations as the previous embodiment.

[0080] As shown in FIG. 9, in the resonator device 1 of this embodiment, the low emissivity layer 71 is omitted from the inner surface of the first lid 3, and instead, a first low emissivity layer 71A having an emissivity lower than that of the second lid 9 is disposed on the inner surface, i.e., the lower surface 9b, of the second lid 9. This makes it difficult for the heat of the heater 5 to escape to the outside of the second package 12. This results in a resonator device 1 in which the inside of the housing section S is heated evenly, the temperature of the resonator element 4 is more stable, and excellent oscillation characteristics can be exhibited. Furthermore, since the heat in the housing section S is difficult to escape, the power consumption of the heater 5 is reduced, resulting in a resonator device 1 that can be driven with low power consumption.

[0081] Since the emissivity of Kovar, the material of the second lid 9, at room temperature is about 0.05, the emissivity of the first low emissivity layer 71A only needs to be less than 0.05. This makes it difficult for heat from the heater 5 to escape to the outside of the second package 12, resulting in an energy-saving resonator device 1 with excellent oscillation characteristics.

[0082] The material of the first low emissivity layer 71A is not particularly limited, but preferably contains at least one of copper, tungsten, aluminum, and gold. These materials are easy to use in semiconductor processes, and the use of these materials makes it easier to manufacture the resonator device 1.

[0083] The above describes the vibration device 1 of the present embodiment. Such a vibration device 1 includes a first package 11 having a vibration element 4, a heater 5 as a heat generating part, a first base 2 on which the vibration element 4 is arranged, and a first lid 3 bonded to the first base 2 so as to accommodate the vibration element 4 between the first base 2 and the first base 2, a second package 12 having a second base 8 on which the first package 11 is arranged, and a second lid 9 bonded to the second base 8 so as to accommodate the first package 11 and the heater 5 between the second base 8, and a first low emissivity layer 71A disposed on the inner surface of the second lid 9 and having an emissivity lower than that of the second lid 9. This makes it difficult for the heat of the heater 5 to escape to the outside of the second package 12 through the second lid 9. Therefore, the inside of the first package 11 is heated evenly, the temperature of the vibration element 4 is more stable, and the vibration device 1 can exhibit excellent oscillation characteristics. Furthermore, the power consumption of the heater 5 is suppressed, and the vibration device 1 can be driven with low power consumption.

[0084] As described above, the second lid 9 is made of Kovar, and the emissivity of the first low emissivity layer 71A at room temperature is less than 0.05. This makes it difficult for the heat of the heater 5 to escape to the outside of the second package 12 through the second lid 9. This results in an energy-saving resonator device 1 that can exhibit excellent oscillation characteristics.

[0085] As described above, the material of the first low emissivity layer 71A includes at least one of copper, tungsten, aluminum, and gold, which makes it easier to manufacture the resonator device 1.

[0086] As described above, the heater 5 is disposed on the first base 2. This allows the heater 5 to be disposed in the vicinity of the vibration element 4, and the vibration element 4 can be heated efficiently.

[0087] The eighth embodiment as described above can also achieve the same effects as the first embodiment.

[0088] However, the resonation device 1 of the present embodiment is not limited thereto. For example, as shown in FIG. 10, the first package 11 may be inverted and the first lid 3 may be disposed facing the bottom surface of the recess 87. In this case, for example, the terminal 650 and the terminal 88 may be electrically connected using a bonding wire BW. Also, as shown in FIG. 11, in the configuration of FIG. 10, a heat insulating layer 100 may be interposed between the first lid 3 and the bottom surface of the recess 87. This makes it possible to suppress the escape of heat to the outside of the second package 12 due to thermal conduction. Also, although not shown, for example, the high emissivity layer 72 of the sixth embodiment described above may be added to the first package 11 in the configurations of FIG. 8 to FIG. 10.

[0089] <Ninth embodiment> FIG. 12 is a cross-sectional view showing a vibration device according to a ninth embodiment.

[0090] This embodiment is similar to the eighth embodiment described above, except that it further includes a second low emissivity layer 71B. In the following description, the differences between this embodiment and the previous embodiment will be mainly described, and the description of the similar points will be omitted. In addition, in the drawings of this embodiment, the same reference numerals are used for the same configurations as the previous embodiment.

[0091] As shown in FIG. 12, the resonator device 1 of this embodiment further includes a second low emissivity layer 71B disposed on the inner surface of the first lid 3 and having an emissivity lower than that of the first lid 3. The second low emissivity layer 71B is the low emissivity layer 71 described above. This makes it difficult for heat in the housing section S to escape to the outside of the first package 11. This results in a resonator device 1 in which the inside of the housing section S is heated evenly and the temperature of the resonator element 4 is more stable, allowing the resonator device 1 to exhibit excellent oscillation characteristics. Furthermore, since the heat in the housing section S is difficult to escape, the power consumption of the heater 5 is reduced, resulting in a resonator device 1 that can be driven with low power consumption.

[0092] Since the emissivity of silicon, which is the material of the first lid 3, at room temperature is about 0.5, the emissivity of the second low emissivity layer 71B at room temperature only needs to be less than 0.5. This makes it difficult for heat to escape from the housing portion S, making it possible to operate the resonator device 1 with low power consumption and excellent oscillation characteristics.

[0093] The material of the second low emissivity layer 71B is not particularly limited, but preferably contains at least one of copper, titanium, tungsten, aluminum, aluminum oxide, gold, chromium, nickel, nickel oxide, platinum, silver, and cobalt. By using these materials, the vibrating device 1 can be easily manufactured.

[0094] As described above, the resonator device 1 of this embodiment has the second low emissivity layer 71B disposed on the inner surface of the first lid 3 and having an emissivity lower than that of the first lid 3. This makes it difficult for heat in the first package 11 to escape to the outside of the first package 11 through the first lid 3. Therefore, the inside of the first package 11 is heated evenly, the temperature of the resonator element 4 is more stable, and the resonator device 1 can exhibit excellent oscillation characteristics. Furthermore, since the heat in the first package 11 is difficult to escape to the outside of the first package 11, the power consumption of the heater 5 is reduced, resulting in a resonator device 1 that can be driven with low power consumption.

[0095] As described above, the first lid 3 is made of silicon, and the emissivity of the second low emissivity layer 71B at room temperature is less than 0.5. This makes it difficult for heat inside the first package 11 to escape to the outside of the first package 11 through the first lid 3. This results in an energy-saving resonator device 1 that can exhibit excellent oscillation characteristics.

[0096] As described above, the material of the second low emissivity layer 71B includes at least one of copper, titanium, tungsten, aluminum, aluminum oxide, gold, chromium, nickel, nickel oxide, platinum, silver, and cobalt, which makes it easier to manufacture the resonator device 1.

[0097] The ninth embodiment as described above can also achieve the same effects as the first embodiment. However, the resonator device 1 of this embodiment is not limited to this. For example, the high emissivity layer 72 described in the sixth embodiment may be added to the first package 11 in the configuration of FIG. 12.

[0098] Tenth embodiment Fig. 13 is a cross-sectional view showing a vibration device according to a tenth embodiment. Figs. 14 to 16 are cross-sectional views showing modified examples of the vibration device of Fig. 13, respectively.

[0099] This embodiment is similar to the seventh embodiment described above, except for the arrangement of the heater 5. 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 each drawing of this embodiment, the same reference numerals are used for the same configurations as the previous embodiment.

[0100] As shown in FIG. 13, in the vibration device 1 of this embodiment, the heater 5 is configured as a separate body from the first base 2. This allows the heater 5 to be made larger and the amount of heat generated to be increased, for example, compared to the seventh embodiment described above. This allows the vibration element 4 to be heated effectively. The heater 5 is configured, for example, to use a silicon substrate as a base material, and a resistor is formed by doping the silicon substrate with impurities such as phosphorus and boron, and the resistor generates heat when a voltage is applied to the resistor. However, the configuration of the heater 5 is not particularly limited.

[0101] Such a heater 5 is disposed on the bottom surface of the second recess 872, and the first package 11 is disposed on the heater 5. In addition, a high emissivity layer 72 is disposed on the upper surface of the heater 5, and a plurality of terminals 59 are disposed on the upper surface of the high emissivity layer 72. Some of the terminals 59 are electrically connected to terminal 650 via bonding member B3, and some of the terminals 59 are electrically connected to terminal 88 via bonding wire BW. In this way, the vibration element 4, the integrated circuit 6, the heater 5, and the terminal 89 are electrically connected to each other.

[0102] The high-emissivity layer 72 has a higher emissivity than that of silicon, which is the base material of the heater 5. This allows the high-emissivity layer 72 to absorb heat from the heater 5 and efficiently release the absorbed heat into the housing section SS. This allows the vibration element 4 to be heated quickly to a desired temperature, resulting in a vibration device 1 with good startup characteristics. In particular, in this embodiment, a portion of the heat absorbed by the high-emissivity layer 72 is transferred to the first package 11 by thermal conduction via the bonding member B3, so that the inside of the first package 11 can be heated more efficiently. This makes the above-mentioned effects more pronounced.

[0103] As described above, since the emissivity of silicon at room temperature is about 0.5, the emissivity of the high emissivity layer 72 at room temperature only needs to be 0.5 or more. This allows the heat of the heater 5 to be more efficiently released into the housing section S, resulting in a vibration device 1 with better startup characteristics.

[0104] The material constituting the high-emissivity layer 72 preferably contains at least one of copper oxide, titanium oxide, silicon oxide, silicon nitride, glass material, aluminum nitride, and platinum black. By using these materials, the vibrating device 1 can be easily manufactured.

[0105] As described above, in the vibration device 1 of this embodiment, the heater 5 is disposed on the second base 8, and the first package 11 is disposed on the heater 5. This allows the heater 5 to be made larger than in the seventh embodiment described above, for example, and the amount of heat generated by the heater 5 to be increased. As a result, the vibration element 4 can be heated effectively.

[0106] The tenth embodiment can also achieve the same effects as the first embodiment described above.

[0107] However, the resonator device 1 of the present embodiment is not limited thereto. For example, as shown in FIG. 14, the first package 11 may be inverted and the first lid 3 may be disposed facing the heater 5. In this case, the terminal 650 and the terminal 59 may be electrically connected using a bonding wire BW. Also, as shown in FIG. 15, in the configuration of FIG. 14, a heat insulating layer 100 may be interposed between the heater 5 and the bottom surface of the recess 87. This can suppress the escape of heat to the outside of the second package 12 due to thermal conduction. Also, as shown in FIG. 16, a high emissivity layer 72B having an emissivity higher than that of the first lid 3 may be disposed on the inner surface of the first lid 3. This allows the high emissivity layer 72B to absorb the heat of the heater 5 transferred to the first lid 3 and efficiently release the absorbed heat into the storage section S. Therefore, the resonator element 4 can be quickly heated to a desired temperature, resulting in a resonator device 1 with good startup characteristics.

[0108] <Eleventh embodiment> FIG. 17 is a cross-sectional view showing a vibration device according to an eleventh embodiment.

[0109] This embodiment is similar to the tenth embodiment described above, except that it further includes a second low-emissivity layer 71B. 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 the drawings of this embodiment, the same reference numerals are used for the same configurations as the previous embodiment.

[0110] As shown in FIG. 17, the resonator device 1 of this embodiment further includes a second low-emissivity layer 71B disposed on the inner surface of the first lid 3 and having an emissivity lower than that of the first lid 3. This makes it difficult for heat in the housing section S to escape to the outside of the first package 11. This results in a resonator device 1 in which the inside of the housing section S is heated evenly and the temperature of the resonator element 4 is more stable, allowing the device 1 to exhibit excellent oscillation characteristics. Furthermore, since it is difficult for heat in the housing section S to escape, the power consumption of the heater 5 is reduced, resulting in a resonator device 1 that can be driven with low power consumption.

[0111] Since the emissivity of silicon, which is the material of the first lid 3, at room temperature is about 0.5, the emissivity of the second low emissivity layer 71B at room temperature only needs to be less than 0.5. This makes it difficult for heat to escape from the housing portion S, making it possible to operate the resonator device 1 with low power consumption and excellent oscillation characteristics.

[0112] The material of the second low emissivity layer 71B is not particularly limited, but preferably contains at least one of copper, titanium, tungsten, aluminum, aluminum oxide, gold, chromium, nickel, nickel oxide, platinum, silver, and cobalt. By using these materials, the vibrating device 1 can be easily manufactured.

[0113] The eleventh embodiment as described above can also achieve the same effects as the first embodiment described above.

[0114] <Twelfth embodiment> FIG. 18 is a cross-sectional view showing a vibration device according to a twelfth embodiment.

[0115] This embodiment is similar to the fifth embodiment described above, except that it has a second package 12 that houses the first package 11, and that the arrangement of the low emissivity layer 71 is different. In the following description, the present embodiment will be described focusing on the differences from the previous embodiments, and the description of the similarities will be omitted. In addition, in the drawings of this embodiment, the same reference numerals are used for the same configurations as the previous embodiments.

[0116] 18, the second package 12 has a second base 8 to which the first package 11 is joined, and a second lid 9 that covers the first package 11 and is joined to an upper surface 8a of the second base 8. The second base 8 and the second lid 9 are made of a substrate made of an insulating material with low thermal conductivity, such as a glass epoxy resin substrate, a paper phenol substrate, a paper epoxy substrate, or a glass composite substrate. This results in a resonator device 1 that is less susceptible to the effects of the ambient temperature.

[0117] Furthermore, a plurality of terminals 88 are arranged on the upper surface 8a of the second base 8, and a plurality of terminals 89 electrically connected to the terminals 88 are arranged on the lower surface 8b of the second base 8. The first package 11 is arranged on the upper surface 8a of the second base 8. The first package 11 is fixed to the second base 8 via a conductive bonding member B3 with the first base 2 facing the second base 8. The terminal 23 and the terminal 88 are electrically connected via the bonding member B3. The second lid 9 has an opening on the lower surface 9b and a bottomed accommodation recess 91 for accommodating the first package 11 therein.

[0118] Also, the low emissivity layer 71 is omitted from the inner surface of the first lid 3, and instead, a first low emissivity layer 71A having an emissivity lower than that of the second lid 9 is disposed on the inner surface of the second lid 9, which in this embodiment is the bottom surface of the accommodation recess 91. This makes it difficult for the heat of the heater 5 to escape to the outside of the second package 12. This results in a vibration device 1 in which the interior of the accommodation section S is heated evenly, the temperature of the vibration element 4 is more stable, and excellent oscillation characteristics can be exhibited. Furthermore, since the heat in the accommodation section S is difficult to escape, the power consumption of the heater 5 is reduced, resulting in a vibration device 1 that can be driven with low power consumption.

[0119] The twelfth embodiment as described above can also achieve the same effects as the first embodiment described above.

[0120] 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.

[0121] In the above-described embodiment, the resonator device 1 is an OCXO (oven-controlled oscillator) having a heater 5 as a heat generating part, but is not limited thereto. That is, the resonator device 1 does not have to be an OCXO (oven-controlled oscillator). In this case, the heat generating part may be, for example, a buffer circuit, a power supply circuit, or the like included in the integrated circuit 6. [Explanation of symbols]

[0122] 1...vibration device, 100...thermal insulation layer, 11...first package, 12...second package, 2...first base, 2a...upper surface, 2b...lower surface, 20...insulating film, 21...through electrode, 22...through electrode, 23...terminal, 25...recess, 26...internal wiring, 27...recess, 271...first recess, 272...second recess, 273...third recess, 28...wiring, 29...wiring, 3...first lid, 3a...upper surface, 3b...lower surface, 31...accommodating recess, 4...vibration element, 41...vibration substrate, 42...electrode, 421...excitation electrode, 422...excitation electrode, 423...terminal, 424...terminal, 425...wiring, 426...wiring, 5...heater, 59...terminal, 6...integrated circuit, 6A...temperature sensor, 6B...oscillating circuit , 6C...temperature compensation circuit, 6D...temperature control circuit, 60...laminated body, 62...wiring layer, 63...insulating layer, 64...passivation film, 65...terminal layer, 650...terminal, 71...low emissivity layer, 71A...first low emissivity layer, 71B...second low emissivity layer, 72...high emissivity layer, 72B...high emissivity layer, 8...second base, 8a...upper surface, 8b...lower surface, 87...recess, 871...first recess, 872...second recess, 88...terminal, 89...terminal, 9...second lid, 9b...lower surface, 91...accommodating recess, B1...bonding member, B2...bonding member, B3...bonding member, BW...bonding wire, Q...metal layer, Q1...first metal layer, Q2...second metal layer, Q3...metal layer, S...accommodating portion, SS...accommodating portion

Claims

1. A vibration element; A heating portion; a first package including a first base on which the vibration element and the heat generating portion are disposed, and a first lid joined to the first base so as to house the vibration element between the first base and a first lid; a low-emissivity layer disposed on an inner surface of the first lid and having an emissivity lower than an emissivity of the first lid; the first base includes a silicon substrate having a first surface and a second surface that are in a reverse relationship, and an integrated circuit formed on the second surface side of the silicon substrate; The vibration device, characterized in that the vibration element and the heat generating portion are arranged on the first surface side of the silicon substrate.

2. the first lid is made of silicon; The vibration device according to claim 1 , wherein the low emissivity layer has an emissivity of less than 0.5 at room temperature.

3. The vibration device according to claim 2 , wherein the low emissivity layer is made of a material that includes at least one of copper, titanium, tungsten, aluminum, aluminum oxide, gold, chromium, nickel, nickel oxide, platinum, silver, and cobalt.

4. a bonding layer that bonds the first lid and the first base; The resonator device according to claim 1 , wherein the low-emissivity layer is made of the same material as the bonding layer.

5. The vibration device according to claim 1 , wherein the low-emissivity layer is also disposed on an outer surface of the first lid.

6. A vibration device as described in any one of claims 1 to 5, comprising a second package having a second base on which the first package is arranged and a second lid joined to the second base so as to accommodate the first package between the second base and a second lid.

7. A vibration element; A heating portion; a first package including a first base on which the vibration element is disposed and a first lid joined to the first base so as to accommodate the vibration element between the first base and a first lid; a second package including a second base on which the first package is disposed and a second lid joined to the second base so as to accommodate the first package and the heat generating portion between the second base and the second lid; a first low-emissivity layer disposed on an inner surface of the second lid, the first low-emissivity layer having an emissivity lower than an emissivity of the second lid; the first base includes a silicon substrate having a first surface and a second surface that are in a reverse relationship, and an integrated circuit formed on the second surface side of the silicon substrate; The vibration device, characterized in that the vibration element is arranged on the first surface side of the silicon substrate.

8. The second lid is made of Kovar. The vibration device according to claim 7 , wherein the first low emissivity layer has an emissivity of less than 0.05 at room temperature.

9. The vibration device according to claim 8 , wherein the first low emissivity layer is made of a material including at least one of copper, tungsten, aluminum, and gold.

10. The vibration device according to claim 7 , further comprising a second low-emissivity layer disposed on an inner surface of the first lid and having an emissivity lower than that of the first lid.

11. the first lid is made of silicon; The vibration device according to claim 10 , wherein the second low emissivity layer has an emissivity of less than 0.5 at room temperature.

12. The vibration device according to claim 11 , wherein the constituent material of the second low emissivity layer includes at least one of copper, titanium, tungsten, aluminum, aluminum oxide, gold, chromium, nickel, nickel oxide, platinum, silver, and cobalt.

13. The vibration device according to claim 7 , wherein the heat generating portion is disposed on the first base.

14. the heat generating portion is disposed on the second base, The resonation device according to claim 7 , wherein the first package is disposed in the heat generating portion.

Images