Aerosol generator, flavor inhaler, and method for manufacturing aerosol generator

Abstract

Provided is an aerosol generator. This aerosol generator comprises a SAW chip. The SAW chip comprises: a piezoelectric element substrate that includes a piezoelectric body; an IDT that is provided on a surface of the piezoelectric element substrate and includes an interdigitated electrode pair; an insulating film that covers the piezoelectric element substrate and the IDT; and a protective film that covers the piezoelectric element substrate, the IDT, and the insulating film.

Description

Aerosol generator, flavor inhaler, and method for manufacturing an aerosol generator

[0001] This invention relates to an aerosol generator, a flavor inhaler, and a method for manufacturing an aerosol generator.

[0002] Conventionally, surface acoustic wave (SWA) devices are known that include a SWA element containing a piezoelectric material, a comb-shaped electrode provided on the surface of the SWA element and composed of a comb-shaped electrode pair, and a surface protective film covering the SWA element and the comb-shaped electrode (see, for example, Patent Document 1).

[0003] Japanese Patent Publication No. 2003-87094

[0004] Patent Document 1 discloses a surface protective film for covering a surface acoustic wave element and a comb-shaped electrode, but from the viewpoint of further quality improvement, there is a need to improve durability.

[0005] One of the objectives of the present invention is to provide an aerosol generator, a flavor inhaler, and a method for manufacturing an aerosol generator with improved durability.

[0006] According to one embodiment, an aerosol generator is provided. This aerosol generator comprises a SAW chip, the SAW chip comprising a piezoelectric element substrate including a piezoelectric material, an IDT (Interdigital Transducer) provided on the surface of the piezoelectric element substrate and including a comb-shaped electrode pair, an insulating film covering the piezoelectric element substrate and the IDT, and a protective film covering the piezoelectric element substrate, the IDT and the insulating film.

[0007] According to the above embodiment, since the SAW chip is equipped with a protective film covering the piezoelectric element substrate, IDT and insulating film, in addition to the insulating film covering the piezoelectric element substrate and IDT, an aerosol generator with improved durability can be provided.

[0008] The insulating film is SiO ２ It may also contain either SiN.

[0009] In this case, the insulating film is SiO ２By including either or SiN, high insulation is achieved between IDTs and between IDTs and the piezoelectric element substrate, allowing the aerosol generator to operate stably.

[0010] The protective film may include DLC (Diamond-Like Carbon).

[0011] In this case, the inclusion of DLC in the protective film suppresses the peeling of the insulating film, as well as the peeling and wear of the protective film itself, thereby improving the durability of the aerosol generator.

[0012] The insulating film may be provided on the surface of the piezoelectric element substrate, at least a portion of the end face of the piezoelectric element substrate, and at the corners between the surface of the piezoelectric element substrate and the end face of the piezoelectric element substrate.

[0013] In this case, by providing the insulating film on the surface of the piezoelectric element substrate, at least a portion of the end face of the piezoelectric element substrate, and at the corners between the surface and end face of the piezoelectric element substrate, peeling of the insulating film can be suppressed, thereby improving the durability of the aerosol generator.

[0014] The protective film may be provided so as to cover the entire surface of the insulating film.

[0015] In this case, the protective film covers the entire surface of the insulating film, thereby suppressing the peeling of the insulating film and improving the durability of the aerosol generator.

[0016] The insulating film may have a thickness of 10 nm to 1400 nm on the surface of the piezoelectric element substrate.

[0017] In this case, by making the insulating film on the surface of the piezoelectric element substrate 10 nm to 1400 nm thick, sufficient insulation can be achieved while suppressing the accumulation of internal stress and improving the durability of the insulating film itself.

[0018] The protective film may have a thickness of 10 nm to 10,000 nm on the surface of the piezoelectric element substrate.

[0019] In this case, by making the protective film on the surface of the piezoelectric element substrate 10 nm to 10,000 nm thick, it is possible to suppress peeling of the insulating film while suppressing the accumulation of internal stress, thereby improving the durability of the protective film itself.

[0020] In another embodiment, a flavor inhaler equipped with the above-described aerosol generator is provided.

[0021] According to the above embodiment, by providing an aerosol generator with improved durability, a flavor inhaler with improved durability can be provided.

[0022] In another embodiment, a method for manufacturing an aerosol generator equipped with a SAW chip is provided. This manufacturing method includes the steps of: forming a plurality of IDTs including comb-shaped electrode pairs on the surface of a wafer of a piezoelectric element substrate containing a piezoelectric material; cutting the wafer into module units; forming an insulating film to cover the cut piezoelectric element substrate and IDTs; and forming a protective film to cover the piezoelectric element substrate, IDTs and insulating film.

[0023] According to the above embodiment, a method for manufacturing an aerosol generator with improved durability can be provided by forming an insulating film that covers the piezoelectric element substrate and the IDT, and further forming a protective film that covers the piezoelectric element substrate, the IDT, and the insulating film.

[0024] In the process of forming the insulating film, the insulating film may be formed by sputtering, CVD (Chemical Vapor Deposition), ALD (Atomic Layer Deposition), or spray coating.

[0025] In this case, by forming the insulating film using one of the following methods—sputtering, CVD, ALD, or spray coating—a uniform and high-quality insulating film can be formed, thereby improving the durability of the aerosol generator.

[0026] In the process of forming the protective film, the protective film may be formed by any of the following methods: sputtering, CVD, ionization deposition, arc deposition, and FCVA (Filtered Cathodic Vacuum Arc).

[0027] In this case, by forming the protective film using one of the following methods—sputtering, CVD, ionization evaporation, arc evaporation, or FCVA—a uniform and high-quality protective film can be formed, thereby improving the durability of the aerosol generator.

[0028] This is a cross-sectional view showing a flavor inhaler according to one embodiment. This is a perspective view showing a SAW tip according to one embodiment. This is a plan view showing a SAW tip according to one embodiment. This is a cross-sectional view showing a SAW tip according to one embodiment. This is a cross-sectional view showing SAW tips according to Comparative Examples 1 to 4 and Example 1. This is a diagram showing the durability test results of SAW tips according to Comparative Examples 1 to 4 and Example 1.

[0029] Embodiments of the present invention will now be described with reference to the drawings. In the drawings described below, the same or corresponding components are denoted by the same reference numerals, and redundant descriptions are omitted. In the following drawings, the dimensions of each part have been appropriately changed for clarity.

[0030] Figure 1 is a cross-sectional view showing a flavor inhaler 100 according to one embodiment of the present invention. As shown in Figure 1, the flavor inhaler 100 comprises an aerosol generator 200 and a mouthpiece 300. The flavor inhaler 100 inhales the aerosol generated by the aerosol generator 200 through the mouthpiece 300, and is, for example, an electronic cigarette device. The aerosol generator 200 has a SAW tip 10 that atomizes the liquid supplied from the liquid storage unit.

[0031] Figure 2 is a perspective view showing a SAW chip 10 according to one embodiment of the present invention. Figure 3 is a plan view showing a SAW chip 10 according to one embodiment of the present invention. Figure 4 is a cross-sectional view showing a SAW chip 10 according to one embodiment of the present invention.

[0032] As shown in FIGS. 2 to 4, the SAW chip 10 includes a piezoelectric element substrate 20, an IDT 30 including an electrode body portion 31 and interdigital electrode pairs 32, a coating layer 40 including an insulating film 41 and a protective film 42, and a heat dissipation mechanism 50. The SAW chip 10 is configured to atomize a liquid by the vibration of a surface acoustic wave (SAW: Surface Acoustic Wave) generated by applying a high-frequency voltage to the interdigital electrode pairs 32.

[0033] The piezoelectric element substrate 20 has a surface 20F on which the electrode body portion 31 and the interdigital electrode pairs 32 of the IDT 30 are disposed, a back surface 20B provided on the opposite side of the surface 20F, an end surface 20E connecting the surface 20F and the back surface 20B, and a corner portion 20C between the surface 20F and the end surface 20E. The piezoelectric element substrate 20 includes a piezoelectric body that expands and contracts by the application of a voltage. The piezoelectric body only needs to constitute at least the surface 20F of the piezoelectric element substrate 20. As the piezoelectric body, a known piezoelectric body composed of ceramics such as quartz, barium titanate, lithium niobate, etc. can be used.

[0034] The electrode body portion 31 is electrically connected to the power source of the fragrance attractor 100. The electrode body portion 31 has a first electrode body portion 31A that is integral with a first interdigital electrode 32A, which is one of the interdigital electrode pairs 32, and a second electrode body portion 31B that is integral with a second interdigital electrode 32B, which is the other of the interdigital electrode pairs 32. The first electrode body portion 31A and the second electrode body portion 31B are arranged to face each other in a direction B orthogonal to the traveling direction A of the SAW. The high-frequency voltage output from the power source is applied to the interdigital electrode pairs 32 through the electrode body portion 31.

[0035] The interdigital electrode pairs 32 have a first interdigital electrode 32A and a second interdigital electrode 32B. The first interdigital electrode <32A> and the second interdigital electrode 32B are alternately arranged in the traveling direction A of the SAW. The first interdigital electrode 32A has a shape that extends from the first electrode body portion 31A toward the second electrode body portion 31B along the orthogonal direction B. The second interdigital electrode 32B has a shape that extends from the second electrode body portion 31B toward the first electrode body portion 31A along the orthogonal direction B. For example, the interdigital electrode pairs 32 are composed of a metal formed by a sputtering method or a vapor deposition method.

[0036] The insulating film 41 is provided so as to cover the surface 20F, end faces 20E, and corner portions 20C of the piezoelectric element substrate 20, and is an insulating film that covers the piezoelectric element substrate 20 and the IDT 30. Note that the insulating film 41 may be partially omitted in regions that do not contribute to the atomization of liquid, such as the end faces 20E of the piezoelectric element substrate 20 parallel to the propagation direction A of the SAW. That is, the insulating film 41 may be provided on at least a part of the surface 20F, end faces 20E, and corner portions 20C of the piezoelectric element substrate 20.

[0037] The insulating film 41 is a material that suppresses the deformation of the piezoelectric element substrate 20 due to the adhesion of liquid or the like, and is preferably composed of a material having a high electrical resistance, a low water permeability, and a Young's modulus, thermal expansion coefficient, and density equivalent to those of the piezoelectric element substrate 20. For example, the insulating film 41 is SiO ２ (silicon dioxide), SiN (silicon nitride), SiON (silicon oxynitride), Teflon (registered trademark), parylene, alumina, benzocyclobutene, polyimide, TaO ２ (tantalum oxide), ZrO ２ (zirconium oxide), HfO ２ (hafnium oxide), TiO ２ (titanium oxide), La ２ O ３ (lanthanum oxide).

[0038] Further, since the insulating film 41 needs to adhere uniformly to the surface 20F, end faces 20E, and corner portions 20C of the piezoelectric element substrate 20, it may be formed by any of sputtering, CVD, ALD, and spray coating. Furthermore, from the viewpoints of ensuring insulation and suppressing internal stress, the insulating film 41 may have a thickness of 10 nm to 1400 nm on the surface 20F of the piezoelectric element substrate 20.

[0039] If the insulating film 41 is formed only on the surface of the IDT 30, that is, if the insulating film 41 is formed only on the surface 20F of the piezoelectric element substrate 20, the insulating film 41 may peel off due to the vibration of the SAW when a liquid is atomized at the end face 20E of the piezoelectric element substrate 20. This is thought to be because the liquid penetrates through the gap between the surface 20F of the piezoelectric element substrate 20 and the insulating film 41, and the atomization of the liquid by the vibration of the SAW pushes the insulating film 41 up from the surface 20F of the piezoelectric element substrate 20, causing it to peel off.

[0040] Therefore, by providing the insulating film 41 so as to cover at least a portion of the surface 20F, end face 20E, and corners 20C of the piezoelectric element substrate 20, contact of liquid with the piezoelectric element substrate 20 can be suppressed, and peeling of the insulating film 41 can be suppressed. In addition, the insulating film 41 may be provided on the back surface 20B of the piezoelectric element substrate 20, in addition to the surface 20F, end face 20E, and corners 20C of the piezoelectric element substrate 20. With such a configuration, contact of liquid with the piezoelectric element substrate 20 can be further suppressed.

[0041] Furthermore, by providing the insulating film 41, even if microcracks are present on the surface 20F of the piezoelectric element substrate 20, the insulating film 41 covers the microcracks, thereby suppressing the occurrence of cracks in the piezoelectric element substrate 20 due to the vibration of the SAW. This is thought to be because the insulating film 41 suppresses the expansion and contraction of the piezoelectric element substrate 20 due to temperature changes caused by a portion of the vibration energy.

[0042] The protective film 42 is provided so as to cover the insulating film 41 and is a film that covers and protects the piezoelectric element substrate 20, IDT 30, and insulating film 41. The protective film 42 may be provided so as to cover the entire surface of the insulating film 41. The protective film 42 is preferably made of a material with high hardness in order to suppress peeling of the insulating film 41. For example, the protective film 42 may be made of DLC.

[0043] Furthermore, since the protective film 42 needs to adhere uniformly to the surface of the insulating film 41, it may be formed by any of the following methods: sputtering, CVD, ionization evaporation, arc, and FCVA. In addition, from the viewpoint of suppressing peeling of the insulating film 41 and suppressing internal stress, the protective film 42 may have a thickness of 10 nm to 10,000 nm on the surface 20F of the piezoelectric element substrate 20.

[0044] By providing a protective film 42 that covers the piezoelectric element substrate 20, IDT 30, and insulating film 41 in addition to the insulating film 41 that covers the piezoelectric element substrate 20 and IDT 30, the peeling of the insulating film 41 can be further suppressed. Furthermore, by having the protective film 42 cover the entire surface of the insulating film 41, the peeling of the insulating film 41 can be further suppressed.

[0045] The heat dissipation mechanism 50 is configured to remove heat generated by the reflection of SAW at the corners 20C of the piezoelectric element substrate 20. The heat dissipation mechanism 50 includes at least one of a heat dissipation layer and a Peltier element, which are made of a material having a higher thermal conductivity than the piezoelectric element substrate 20.

[0046] In this embodiment, the heat dissipation mechanism 50 is a heat dissipation layer disposed on the back surface 20B of the piezoelectric element substrate 20. However, this embodiment is not limited thereto. For example, the heat dissipation mechanism 50 only needs to be in contact with the piezoelectric element substrate 20, and may be disposed on the front surface 20F of the piezoelectric element substrate 20. The heat dissipation mechanism 50 may be a Peltier element. The heat dissipation mechanism 50 may include both a heat dissipation layer and a Peltier element.

[0047] For example, the heat dissipation layer may be made of metal such as aluminum, copper, or iron, or it may be made of carbon, aluminum nitride, or ceramic. For example, the Peltier element may be bonded to the piezoelectric element substrate 20 with an adhesive (grease, epoxy resin, metal paste). The thermal conductivity of the adhesive is preferably higher than 0.1 W / m / K. Furthermore, the thermal conductivity of the adhesive is preferably higher than 0.5 W / m / K. A thin adhesive layer is desirable, and a thin adhesive layer can be achieved by screen printing.

[0048] A liquid supply unit 60 is provided on the back surface 20B of the piezoelectric element substrate 20, configured to supply liquid to the piezoelectric element substrate 20. The liquid supply unit 60 supplies liquid to the front surface 20F of the piezoelectric element substrate 20 via the end surface 20E of the piezoelectric element substrate 20. For example, the liquid supply unit 60 is a syringe pump. The syringe pump may be manually operated or electrically operated. The liquid supply unit 60 may also be a component that supplies liquid by capillary action.

[0049] If the liquid storage unit is a cartridge, the liquid supply unit 60 may automatically supply liquid to the SAW tip 10 in accordance with the installation of the cartridge. If the liquid supply unit 60 is provided with a power switch for driving the flavor inhaler 100, the liquid supply unit 60 may automatically supply liquid to the SAW tip 10 in accordance with the turning on of the power switch.

[0050] The following describes how to manufacture the aerosol generator 200 equipped with the SAW chip 10 according to this embodiment. First, a plurality of IDTs 30, each containing a comb-shaped electrode pair 32, are formed on the surface of a wafer of the piezoelectric element substrate 20 containing a piezoelectric material. Next, the wafer on which the IDTs 30 are formed is cut into module units of the SAW chip 10.

[0051] Next, an insulating film 41 is formed to cover the cut piezoelectric element substrate 20 and IDT 30. In this step, the insulating film 41 may be formed on the surface 20F, end face 20E, and corner portion 20C of the piezoelectric element substrate 20. At this time, the insulating film 41 may be formed by sputtering, CVD, ALD, or spray coating.

[0052] Next, a protective film 42 is formed to cover the piezoelectric element substrate 20, the IDT 30, and the insulating film 41. In this step of forming the protective film 42, the protective film 42 may be formed so as to cover the entire surface of the insulating film 41. At this time, the protective film 42 may be formed by any of the following methods: sputtering, CVD, ionization evaporation, arc, and FCVA.

[0053] The inventors then conducted tests on the durability of the SAW chip. Specifically, the inventors first formed an IDT 30 including a comb-shaped electrode pair 32 on a piezoelectric element substrate 20 containing lithium niobate as the piezoelectric material, and then used this as a base to manufacture SAW chips according to Comparative Examples 1 to 4 and Example 1, by selecting the configuration of the coating layer (presence or absence and material of the insulating film 41, and presence or absence of the protective film 42) as shown below. Figure 5 is a cross-sectional view showing the SAW chips according to Comparative Examples 1 to 4 and Example 1.

[0054] Comparative Example 1 (Figure 5(a)) The SAW chip according to Comparative Example 1 is one in which an insulating film 41 and a protective film 42 are not formed on the piezoelectric element substrate 20 on which the IDT 30 is formed.

[0055] Comparative Example 2 (Figure 5(b)) The SAW chip according to Comparative Example 2 has a piezoelectric element substrate 20 on which an IDT 30 is formed, and SiO ２ The insulating film 41, composed of SiO, is formed by plasma CVD. ２ The deposition conditions for the insulating film 41, which is composed of the following, are: pressure: 60 Pa, temperature: 300 °C, and plasma applied power: 1.2 W / cm². ２ , precursor (Bis (ethylmethylamino) silane) flow rate: 5 to 10 sccm, Ar flow rate: 100 sccm, O ２ The flow rate was set to 150 sccm, and the ES (electrode-substrate) distance was 30 mm. The thickness of the formed insulating film 41 was 1200 nm.

[0056] Comparative Example 3 (Figure 5(c)) The SAW chip according to Comparative Example 3 is formed on a piezoelectric element substrate 20 on which an IDT 30 is formed, by plasma CVD with an insulating film 41 made of SiN. Here, the film formation conditions for the insulating film 41 made of SiN are: pressure: 60 Pa, temperature: 300 °C, plasma applied power: 0.85 W / cm². ２ , precursor (Bis (ethylmethylamino) silane) flow rate: 5 to 10 sccm, Ar flow rate: 100 sccm, NH ３ The flow rate was set to 100 sccm, and the ES (electrode-substrate) distance was 30 mm. The thickness of the formed insulating film 41 was 1200 nm.

[0057] Comparative Example 4 (Figure 5(d)) The SAW chip according to Comparative Example 4 is formed by forming a protective film 42 made of DLC on a piezoelectric element substrate 20 on which an IDT 30 is formed, using an arc method. Here, the protective film 42 made of DLC is formed using a graphite target as the cathode soot material, and the film formation conditions are: operating pressure / atmosphere: 4.0 × 10 －４ The settings were: Pa, arc current: 40A, substrate bias voltage: -200V, deposition time: 30 minutes. The deposition conditions were: operating pressure / atmosphere: 1.0 × 10⁻⁶ －４ ~1.0 x 10 －２ Pa, arc current: 50A or less, substrate bias voltage: -50 to -500V, and film deposition time can be appropriately set within the range of 0 to 60 minutes. The thickness of the formed protective film 42 is 90 nm.

[0058] Example 1 (Figure 5(e)) The SAW chip 10 according to Example 1 is formed on a piezoelectric element substrate 20 on which an IDT 30 is formed, by forming an insulating film 41 made of SiN by plasma CVD and a protective film 42 made of DLC by arc CVD. Here, the film formation conditions for the insulating film 41 made of SiN and the protective film 42 made of DLC are the same as those shown in Comparative Examples 3 and 4.

[0059] Next, the inventors repeatedly drove the SAW chips according to Comparative Examples 1 to 4 and Example 1, and measured the number of repetitions until the SAW chip could be driven, or the number of repetitions before the peeling of the insulating film 41 and / or protective film 42 progressed and the risk of exposure of the piezoelectric element substrate 20 occurred, as the "number of repetitions to reach durability test." When comparing Comparative Examples 1 to 4 with Example 1, it is desirable that the number of repetitions to reach durability test for Example 1 be significantly higher than that for Comparative Examples 1 to 4.

[0060] The driving conditions for the SAW chip were a liquid supply rate of 3 ul / sec and a driving power of 8 W, and the operation consisted of repeating a 3-second driving (atomization) cycle with a 3-second interval. The inventors measured the thickness of the insulating film 41 and / or protective film 42 using a step meter, and determined whether there was a risk of the insulating film 41 and / or protective film 42 peeling off and the piezoelectric element substrate 20 being exposed based on the results of the step meter and visual inspection of the surface condition with a microscope.

[0061] Figure 6 shows the durability test results of the SAW chips according to Comparative Examples 1 to 4 and Example 1. In Figure 6, initial peeling indicates whether or not the insulating film 41 and / or protective film 42 peeled off before the SAW chip was driven, electrical characteristics indicate whether or not it had electrical resistance (insulation) above a predetermined value, and atomization amount indicates whether or not an aerosol above a predetermined amount was generated. These were evaluated with ○, △, and × respectively.

[0062] As shown in Figure 6, in Comparative Example 1, since the insulating film 41 and protective film 42 were not formed, cracks occurred in the piezoelectric element substrate 20 after the SAW chip was driven 10 times, making it impossible to drive.

[0063] In Comparative Example 2, SiO ２ Initial peeling of the insulating film 41 was observed, and after 600 cycles of driving the SAW chip, it was confirmed that the peeling of the insulating film 41 progressed, creating a risk of exposure of the piezoelectric element substrate 20. Due to the peeling of the insulating film 41, the entire surface of the SAW chip was not completely covered, and if the SAW chip was driven in this state, the piezoelectric element substrate 20 would be exposed, potentially approaching the undesirable state of Comparative Example 1.

[0064] Furthermore, in Comparative Example 3, it was confirmed that after 2000 cycles of driving the SAW chip, peeling of the insulating film 41, which is made of SiN, occurred and progressed, creating a risk of exposing the piezoelectric element substrate 20. Due to the peeling of the insulating film 41, the entire surface of the SAW chip was not completely covered, and if the driving of the SAW chip continued in this state, the piezoelectric element substrate 20 would be exposed, potentially approaching the undesirable state of Comparative Example 1. Note that in Comparative Example 3, which used an insulating film 41 made of SiN, SiO ２ Compared to Comparative Example 2, which used an insulating film 41 composed of the above, it was confirmed that the area of ​​the peeled area was smaller and the degree of peeling was reduced.

[0065] Furthermore, in Comparative Example 4, initial peeling of the protective film 42 made of DLC was observed, and because DLC is conductive, the SAW chip could not be energized due to insulation failure.

[0066] In contrast, in Example 1, no peeling of the insulating film 41 made of SiN and / or the protective film 42 made of DLC was observed until the SAW chip 10 was driven 7,000 times. In other words, it was confirmed that the number of times required to reach the durability test in Example 1 was significantly higher than the number of times required to reach the durability test in Comparative Examples 1 to 4. Furthermore, in Example 1 after 7,000 drives, it was confirmed that the area of ​​the peeled area was very small and the thickness of the peeled film was thinner compared to Comparative Examples 2 and 3. In particular, the shape of the peeled area became point-like, and the film surface appeared to be abraded rather than peeling, which indicates that the durability in Example 1 was improved.

[0067] According to the aerosol generator 200 equipped with the SAW chip 10 with the above configuration, the SAW chip 10 is equipped with a protective film 42 that covers the piezoelectric element substrate 20, the IDT 30 and the insulating film 41, in addition to the insulating film 41 that covers the piezoelectric element substrate 20 and the IDT 30, thus providing an aerosol generator 200 with improved durability.

[0068] Also, the insulating film 41 is SiO ２If either or SiN is included, high insulation is achieved between the IDTs 30 and between the IDTs 30 and the piezoelectric element substrate 20, so that the aerosol generator 200 can be operated stably.

[0069] Furthermore, if the protective film 42 contains DLC, it is possible to suppress the peeling of the insulating film 41 and also suppress the peeling and wear of the protective film 42 itself, thereby improving the durability of the aerosol generator 200.

[0070] Furthermore, if the insulating film 41 is provided on the surface 20F of the piezoelectric element substrate 20, at least a portion of the end face 20E of the piezoelectric element substrate 20, and the corner 20C between the surface 20F and the end face 20E of the piezoelectric element substrate 20, peeling of the insulating film 41 can be suppressed, thereby improving the durability of the aerosol generator 200.

[0071] Furthermore, if the protective film 42 covers the entire surface of the insulating film 41, peeling of the insulating film 41 can be suppressed, thereby improving the durability of the aerosol generator 200.

[0072] Furthermore, when the insulating film 41 on the surface of the piezoelectric element substrate 20 has a thickness of 10 nm to 1400 nm, it is possible to achieve sufficient insulation while suppressing the accumulation of internal stress and improving the durability of the insulating film 41 itself.

[0073] Furthermore, when the protective film 42 on the surface of the piezoelectric element substrate 20 has a thickness of 10 nm to 10,000 nm, it is possible to suppress the peeling of the insulating film 41 while suppressing the accumulation of internal stress, thereby improving the durability of the protective film 42 itself.

[0074] Furthermore, by providing a flavor inhaler 100 equipped with the aerosol generator 200 with the above configuration, it is possible to provide a flavor inhaler 100 with improved durability by equipping it with an aerosol generator 200 with improved durability.

[0075] Furthermore, the manufacturing method for the aerosol generator 200 equipped with the above-described SAW chip 10 provides an improved durability by forming an insulating film 41 that covers the piezoelectric element substrate 20 and the IDT 30, and further forming a protective film 42 that covers the piezoelectric element substrate 20, the IDT 30, and the insulating film 41.

[0076] Furthermore, in the process of forming the insulating film 41, if the insulating film 41 is formed by sputtering, CVD, ALD, or spray coating, a uniform and high-quality insulating film 41 can be formed, thereby improving the durability of the aerosol generator 200.

[0077] Furthermore, in the process of forming the protective film 42, by forming the protective film 42 using one of the following methods: sputtering, CVD, ionization evaporation, arc, or FCVA, a uniform and high-quality protective film 42 can be formed, thereby improving the durability of the aerosol generator 200.

[0078] While embodiments of the present invention have been described above, these embodiments are intended to facilitate understanding of the present invention and do not limit it. The present invention can be modified and improved without departing from its spirit, and its equivalents are included. Furthermore, combinations or omissions of the components described in the claims and specification are possible to the extent that at least some of the above-mentioned problems can be solved or at least some of the effects can be achieved.

[0079] In the embodiments of the present invention, an aerosol generator equipped with a SAW chip was used as an example for explanation. However, the configuration in which an insulating film and protective film are formed to cover the substrate and electrodes is not limited to an aerosol generator equipped with a SAW chip. For example, in drug aspirators such as medical ultrasonic nebulizers, an insulating film and protective film may be formed to cover the substrate and electrodes.

[0080] Some embodiments disclosed herein are described below. A first embodiment of the present invention is an aerosol generator equipped with a SAW chip, the SAW chip comprising a piezoelectric element substrate including a piezoelectric material, an IDT provided on the surface of the piezoelectric element substrate and including a comb-shaped electrode pair, an insulating film covering the piezoelectric element substrate and the IDT, and a protective film covering the piezoelectric element substrate, the IDT and the insulating film. In a second embodiment of the present invention, in the first embodiment, the insulating film is SiO ２ The invention includes either or SiN. In a third aspect of the present invention, in the first or second aspect, the protective film includes DLC. In a fourth aspect of the present invention, in any of the first to third aspects, the insulating film is provided on the surface of the piezoelectric element substrate, at least a portion of the end face of the piezoelectric element substrate, and at the corners between the surface of the piezoelectric element substrate and the end face of the piezoelectric element substrate. In a fifth aspect of the present invention, in the fourth aspect, the protective film is provided so as to cover the entire surface of the insulating film. In a sixth aspect of the present invention, in any of the first to fifth aspects, the insulating film has a thickness of 10 nm to 1400 nm on the surface of the piezoelectric element substrate. In a seventh aspect of the present invention, in any of the first to sixth aspects, the protective film has a thickness of 10 nm to 10000 nm on the surface of the piezoelectric element substrate. An eighth aspect of the present invention is a flavor inhaler comprising an aerosol generator in any of the first to seventh aspects. A ninth aspect of the present invention is a method for manufacturing an aerosol generator equipped with a SAW chip, comprising the steps of: forming a plurality of IDTs including comb-shaped electrode pairs on the surface of a wafer of a piezoelectric element substrate containing a piezoelectric material; cutting the wafer into module units; forming an insulating film to cover the cut piezoelectric element substrate and IDTs; and forming a protective film to cover the piezoelectric element substrate, IDTs, and insulating film. In a tenth aspect of the present invention, in the ninth aspect, the insulating film is formed by any of sputtering, CVD, ALD, and spray coating in the step of forming the insulating film. In an eleventh aspect of the present invention, in the ninth or tenth aspect, the protective film is formed by any of sputtering, CVD, ionization evaporation, arc, and FCVA in the step of forming the protective film.

[0081] 10...SAW chip 20...Piezoelectric element substrate 20C...Corner 20E...End face 20F...Surface 30...IDT 32...Comb-shaped electrode pair 41...Insulating film 42...Protective film

Claims

1. An aerosol generator equipped with a SAW chip, wherein the SAW chip comprises: a piezoelectric element substrate including a piezoelectric material; an IDT provided on the surface of the piezoelectric element substrate and including a comb-shaped electrode pair; an insulating film covering the piezoelectric element substrate and the IDT; and a protective film covering the piezoelectric element substrate, the IDT and the insulating film.

2. An aerosol generator according to claim 1, wherein the insulating film is SiO ２ An aerosol generator containing either or SiN.

3. An aerosol generator according to claim 1 or claim 2, wherein the protective film includes DLC.

4. An aerosol generator according to any one of claims 1 to 3, wherein the insulating film is provided on the surface of the piezoelectric element substrate, at least a portion of the end face of the piezoelectric element substrate, and at the corner between the surface of the piezoelectric element substrate and the end face of the piezoelectric element substrate.

5. An aerosol generator according to claim 4, wherein the protective film is provided so as to cover the entire surface of the insulating film.

6. An aerosol generator according to any one of claims 1 to 5, wherein the insulating film has a thickness of 10 nm to 1400 nm on the surface of the piezoelectric element substrate.

7. An aerosol generator according to any one of claims 1 to 6, wherein the protective film has a thickness of 10 nm to 10,000 nm on the surface of the piezoelectric element substrate.

8. A flavor inhaler equipped with an aerosol generator according to any one of claims 1 to 7.

9. A method for manufacturing an aerosol generator equipped with a SAW chip, comprising the steps of: forming a plurality of IDTs including comb-shaped electrode pairs on the surface of a wafer of a piezoelectric element substrate containing a piezoelectric material; cutting the wafer into module units; forming an insulating film to cover the cut piezoelectric element substrate and the IDTs; and forming a protective film to cover the piezoelectric element substrate, the IDTs and the insulating film.

10. A method for manufacturing an aerosol generator according to claim 9, wherein in the step of forming the insulating film, the insulating film is formed by any of sputtering, CVD, ALD, and spray coating.

11. A method for manufacturing an aerosol generator according to claim 9 or claim 10, wherein in the step of forming the protective film, the protective film is formed by any of the following: sputtering, CVD, ionization evaporation, arc, and FCVA.

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