JP2003092797A - Manufacturing method of ultrasonic wave vibrator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of an ultrasonic wave vibrator that can manufacture compact ultrasonic wave vibrators with high performance and excellent reliability without the need for using adhesive and for cutting process. SOLUTION: This invention provides the manufacturing method of the ultrasonic wave vibrator 11A having a piezoelectric thin film 17 being a piezoelectric element, an upper resonator 22 and a lower resonator 25 for clamping the piezoelectric thin film 17 from both sides as components, and is characterized in that ultra-fine particles 40 are jetted and deposited on the upper resonator 22 clamping the piezoelectric thin film 17 inbetween to form a diaphragm 38.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an ultrasonic vibrator, and more particularly to an ultrasonic vibrator using an electro-mechanical energy conversion element by a piezoelectric element, which is used as a driving source for an ultrasonic actuator or the like. Manufacturing method.

[0002]

2. Description of the Related Art In recent years, an ultrasonic motor has attracted attention as a new motor replacing an electromagnetic motor, and several ultrasonic actuators have been proposed so far. For example,
In the woodpecker type ultrasonic motor as shown in FIG. 18, the contact surface of the driven member such as the rotor 93 vibrates at the tip of the vibrating piece 92 attached to the end face of the Langevin type ultrasonic transducer 91. Slightly tilted with respect to the piece 92 (tilt angle θ)
The rotor 93 is driven by bringing them into contact with each other and vibrating the ultrasonic vibrator 91 to vibrate the vibrating piece 92 in the longitudinal direction.

The Langevin type ultrasonic transducer 91 used here has a shape of several mm in diameter, as shown in FIG.
A cylindrical shape having a length of several tens of mm and a length of several mm to 100 mm is generally used, and the piezoelectric element 94 is sandwiched between the resonators 95 made of a metallic block. These components are generally connected by fastening a bolt 96.

[0004]

However, the structure and manufacturing method of the prior art described above have some drawbacks as described below. That is, when the ultrasonic motor of the prior art is to be realized as a drive source of a microstructure represented by a micromachine, the size thereof is, for example, about 1 mm, and therefore, the bolt fastening structure as described above is used for fastening. This cannot be achieved due to the lack of mechanical strength of the part.

Further, when adhesive is used as a joining method instead of bolt fastening, an adhesive layer is interposed between the respective members of the ultrasonic transducer, so that attenuation of ultrasonic waves in the layers and ultrasonic waves at the interface The peeling of the joint or the like occurs due to the stress applied by the reflection / ultrasonic vibration, and the performance / reliability of the ultrasonic vibrator is deteriorated.

This problem is caused by the peeling of the bonding layer due to the stress applied at the time of cutting when a small ultrasonic vibrator is obtained by cutting the large ultrasonic vibrator after cutting it. , Especially noticeable.

The present invention was developed in view of the above problems in the prior art, and it is small in size, high in performance and excellent in reliability, does not use a bonding step and does not require a cutting step, and is free from the intrusion of moisture. It is an object of the present invention to provide a method for manufacturing an ultrasonic vibrator, which can prevent scratches and can be easily processed for wiring.

[0008]

The invention according to claim 1 is
A method of manufacturing an ultrasonic transducer, comprising a piezoelectric element and a resonator sandwiching the piezoelectric element from both sides as constituent members, wherein ultrafine particles are jet-deposited on the resonator sandwiching the piezoelectric element to form a resonator element. It is characterized by.

According to a second aspect of the present invention, there is provided a method of manufacturing an ultrasonic vibrator having a piezoelectric element and a resonator sandwiching the piezoelectric element from both sides as a constituent member, wherein the piezoelectric element and the piezoelectric element are sandwiched from both sides. After forming the resonator, the coating layer is formed by spraying and depositing ultrafine particles of an insulating material or metal on these side surfaces.

According to a third aspect of the present invention, there is provided a method of manufacturing an ultrasonic vibrator, comprising a piezoelectric element and a resonator made of an insulating material sandwiching the piezoelectric element from both sides as constituent members. Is formed, and the connection terminal and the upper electrode and the lower electrode of the piezoelectric element are connected by a conductor layer formed by jet deposition of ultrafine particles.

In the present invention, a method is basically used in which the electrodes, the piezoelectric layer, and the like are laminated and formed by jet deposition in the state of ultrafine particles on a substrate heated from a nozzle. This method is explained below. 1 to 3 show the principle of a manufacturing method in which an electrode, a piezoelectric layer, and the like are jet-deposited in a state of ultrafine particles from a nozzle onto a substrate. This manufacturing method is a known method, and is disclosed in JP-A-4-188503 and Kashu: “Gas deposition of ultrafine particles”, vacuum.
vol. 35, No. 7, 1992, pp649-pp
653 and the like.

In the above method, the ultrafine particles 1 produced or prepared in the ultrafine particle producing chamber 2 are guided to the film forming chamber by the carrier gas 4 through the carrier pipe 3 and jetted from the nozzle 5 onto the substrate 6 at a high speed. This is a method in which the film 7 having a thickness of several μm to several tens μm and having a pattern corresponding to the emission end shape can be directly formed with high accuracy.

The features of this method are that a mixed and uniform film of multi-elements can be obtained. Pattern formation is possible without using a mask. Film formation speed is high. Film density control is possible. Low temperature film formation. It is mentioned that is possible. Further, it has been reported that the strength of the formed film 7 and the adhesion strength to the substrate 6 are high, and a dense formed body can be obtained.

At the time of depositing a metal electrode, the metal is heated and evaporated by a resistance heating method, an induction heating method, an arc heating method, an induction plasma heating method, a laser heating method, etc., and by collision with an inert gas atom. Ultrafine particles 1 are generated, introduced into a carrier pipe 3 together with a carrier gas 4 which is an inert gas, and sprayed from a nozzle 5 toward a substrate 6. On the other hand, for the piezoelectric film formation, for example, PZT ultrafine particle powder prepared by the alkoxide method is placed in the ultrafine particle generation chamber, the ultrafine powder is floated up by the carrier gas 4, and the ultrafine powder that has risen is transferred to the carrier pipe 3 by the carrier gas 4. It is introduced and jetted from the nozzle 5 toward the substrate 6.

In this method, the ultrafine powder may be any of metal, glass, ceramics, and plastic, and the same material can be used for the substrate 6. further,
This method also has a feature that thin film or thick film lamination of different materials can be carried out at once by preparing a plurality of nozzles 5.

According to the first aspect of the present invention, by adopting the above-mentioned method, the ultrafine particles are jet-deposited on the resonator sandwiching the piezoelectric element to form the vibrating piece, so that machining such as cutting is not used. The resonator element can be integrally formed on the resonator.

According to a second aspect of the present invention, after the piezoelectric element and the resonator sandwiching the piezoelectric element from both sides are formed by using the above-described method, the insulating material or the metal ultrafine particles are jet-deposited on these side surfaces. By forming the coating layer, it is possible to prevent water from entering the ultrasonic transducer and damage it.

According to a third aspect of the present invention, the connection terminal is formed on the resonator by using the above-mentioned method, and the connection terminal and the upper electrode and the lower electrode formed on the piezoelectric element are formed by jet deposition of ultrafine particles. The wiring required for driving the ultrasonic transducer may be connected to the connection terminal, and the piezoelectric element forming the ultrasonic transducer may be damaged by heat during wiring. Will disappear.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (Embodiment 1) FIGS. 4 to 10
Shows Embodiment 1 of the present invention, FIG. 4 to FIG. 7 are side views showing respective processing processes, FIG. 8 is a side view of the formed ultrasonic transducer (before forming the vibrating piece 38), and FIG. FIG. 10 is a side view showing a processing process of an ultrasonic transducer having a vibrating piece 38, and FIG. 10 is a side view showing a modified example of the first embodiment.

In the first embodiment, the lower resonator 25 made of an aluminum cylinder is heated, and platinum fine particles 19 are formed on the upper surface of the lower resonator 25 from the nozzle 12 as the lower electrode ultrafine particles 19 as shown in FIG. The lower electrode 16 is formed by spray deposition. Then, as shown in FIG.
The PZT ultrafine particles are jet-deposited from the nozzle 13 as the ultrafine particles 20 for the piezoelectric thin film to form the piezoelectric thin film 17 which functions as a piezoelectric element. This is 500 ℃ ~ 10
Heat treatment is performed in an oxygen atmosphere at 00 ° C.

Thereafter, as shown in FIG. 6, copper ultrafine particles are jet-deposited from the nozzle 14 as the ultrafine particles 21 for the upper electrode to form the upper electrode 18, and further, as shown in FIG. Ultrafine aluminum particles are spray-deposited as ultrafine particles 24 for forming a layered film of the upper resonator 22.

As a result, the ultrasonic transducer 11 (before forming the vibrating piece 38) shown in FIG. 8 can be obtained. The polarization of the piezoelectric element and the excitation of the ultrasonic transducer 11 are performed by applying a voltage to the upper electrode 18 and the lower electrode 16 via the lead wire 28 and the lead wire 29 connected as shown in FIG.

Further, in the first embodiment, the nozzle 39 for the ultrafine particles of the vibrating element material, the cross-sectional shape of which corresponds to the cross-sectional shape of the vibrating element 38, is used, and as shown in FIG. Ultrafine particles 40 for the vibrating piece material are jetted from the nozzle 39 to the upper surface of the. The ultrafine particles 40 are the same as the ultrafine particles 24 for the upper resonator material. As the deposition of the ultrafine particles 40 progresses, the distance between the surface of the upper resonator 22 and the nozzle 39 is relatively increased, and the vibrating piece 38 having a predetermined length is deposited.

According to the first embodiment, the ultrasonic transducer 11A for the ultrasonic actuator in which the vibrating piece 38 and the upper resonator 22 are integrally formed is manufactured.

According to the first embodiment, the resonator element 38 can be formed on the upper resonator 22 without using machining such as cutting. As a result, the deformation due to the stress applied by the machining, which is a problem particularly when the ultrasonic transducer 11A is downsized, does not occur. Further, the workpiece is held only by placing it, which makes it extremely easy to hold the workpiece when the size is reduced. Therefore, the miniaturized ultrasonic transducer 11A for the ultrasonic actuator can be obtained at low cost with good yield.

As shown in FIG. 10, following the formation of the vibrating piece 38, ultra fine particles 43 for the sliding portion material are jet-deposited from the nozzle 32 on the end surface of the vibrating piece 38 to form the sliding member 41. It is also possible to do so. As the sliding member 41, ceramic materials such as silicon carbide, silicon nitride and alumite oxalate, solid lubricants such as molybdenum disulfide and fluororesin, resin materials alone such as polyimide, fibers and whiskers such as resin and ceramics and glass. And the like are possible.

Further, in the first embodiment, the cross-sectional shape of the nozzle 39 corresponds to the shape of the vibrating piece 38, but the present invention is not limited to this, and a forming method by scanning this as a small-diameter nozzle. Is also possible. Further, using this method, from the formation of the resonator to the formation of the resonator element 38,
It is also possible to carry out in one step using the same nozzle.

According to the first embodiment, the respective members constituting the formed ultrasonic transducer 11 or 11A are firmly joined without an adhesive layer interposed. Therefore, the mechanical strength is excellent, and peeling of the bonding layer due to reflection of ultrasonic waves and ultrasonic vibration does not occur at the bonding portion. Therefore, the ultrasonic transducer 11 or 11A having high performance and high reliability can be obtained.

The plane shape, thickness, etc. of each layer described above can be arbitrarily determined by controlling the shape of the nozzle and the ejection conditions. Therefore, the planar shape of the ultrasonic transducer 11 or 11A is not limited to a simple shape such as a square or a circle, and can be any shape. Also, if the shape is the same, ultrasonic transducers having a plurality of oscillation frequencies can be easily manufactured by changing the deposition amounts of the piezoelectric material ultrafine particles and the resonator material ultrafine particles in the same apparatus.

Further, as the ultrafine particles for the resonator material, any material can be used as long as it is a material such as glass, ceramics, metal or the like that has a small attenuation of ultrasonic waves in the member.
Similarly, the electrode material is not limited to platinum, and it is also possible to simultaneously deposit a conductor metal or metal powder and ceramic powder. It is also easy to deposit tin on the outermost surface of the electrode of the multilayer film so that it can be soldered.

Further, although the case where only the lower resonator 25 is formed by the conventional method has been described in the first embodiment, only one member of the piezoelectric element and the upper and lower resonators is spray deposited. The ultrasonic transducer 11 or 11A may be formed by the method.

Further, although both the electrodes on the upper and lower surfaces of the piezoelectric element are formed by the jet deposition method, it goes without saying that they can also be formed by a conventional method such as vapor deposition, plating, sputtering and baking.

(Second Embodiment) FIG. 11 shows the second embodiment.
FIG. In the second embodiment, a coating layer of insulating resin, ceramics, glass, metal or the like is provided on the side surface of the ultrasonic vibrator 11 before forming the resonator element 38 in the first embodiment, where the piezoelectric element and the electrode are exposed. The coating layer 34 was formed by jet-depositing the ultrafine particles 49 for the material from the nozzle 50.

The coating layer 34 is formed by arranging the coating layer forming surface on the ultrasonic transducer 11 and the nozzle 50 so as to intersect perpendicularly, and moving the positions of both relatively. For example, in the case of the cylindrical ultrasonic vibrator 11, the nozzle may be fixed and the ultrasonic vibrator may be rotated as illustrated.

According to the second embodiment, the ultrasonic transducer 1
1 can be protected against invasion of moisture, scratches and the like.
Here, since the surface to be protected can be strictly selected by using the jet deposition method, the vibration mode is not changed by adding unnecessary mass to the piezoelectric element, and the electrode terminals necessary for mounting are not polluted at all. The coating layer 34 can be coated. Therefore, it is possible to obtain the ultrasonic transducer 11 having excellent environmental resistance and high reliability.

(Third Embodiment) FIGS. 12 to 17 are perspective views showing a processing process of the third embodiment. The ultrasonic transducer 11 formed in the third embodiment is the same as the ultrasonic transducer 11 formed in the first embodiment.

In the third embodiment, the lower resonator 2
5 is formed of an insulating member, and an electric terminal 35 for the lower electrode is provided on the lower resonator 25 as shown in FIG.

Further, as shown in FIGS. 12 and 13, after the lower electrode 16 is deposited by spraying, the lower electrode 16 is extended to form the electrical terminal 35 for the lower electrode shown in FIGS. 14 and 15.
A wiring pattern 37 of a conductor that connects the lower electrode 16 and the lower electrode 16 is formed by scanning the nozzle 12. The wiring pattern 37 is formed by relatively moving the positions of the wiring pattern formation surface on the ultrasonic transducer 11 and the nozzle 12 so that the nozzle 12 intersects vertically (FIG. 13; arrow 47 direction). To do.

Subsequently, as shown in FIG. 15, the piezoelectric thin film 17 is formed.
Then, insulating particles are sprayed and deposited from the nozzle 46 to form a lower electrode insulating band 45 for electrically insulating the upper electrode 18 and the lower electrode 16 shown in FIG.

Then, as shown in FIG. 16, the upper electrode 1
8 is formed by jet deposition of conductor particles, and an electrical terminal 36 for an upper electrode and an upper electrode 18 formed in the same manner as the lower electrode 16 are formed as an extension of the wiring pattern 48 shown in FIG.
To electrically connect.

In the third embodiment, as shown in FIG. 17, wiring patterns 37 and 48 electrically connect the lower electrode electric terminal 35 and the lower electrode 16, and the upper electrode electric terminal 36 and the upper electrode 18. It

According to the third embodiment, the ultrasonic transducer 1
The wiring to 1 may be made to the lower electrode electric terminal 35 and the upper electrode electric terminal 36. Therefore, the ultrasonic transducer 11 is not damaged by heat or the like during wiring. Further, the shapes of the lower electrode electric terminal 35 and the upper electrode electric terminal 36 do not affect the characteristics of the ultrasonic transducer 11 at all, and can be set arbitrarily. Therefore, the terminal shape can be set on the assumption that the terminal is mounted on the device, and the manufacturing efficiency as a whole including the mounting step can be improved.

In the third embodiment, the electric terminal 3 for the lower electrode is formed before the completion of the forming process of the ultrasonic transducer 11.
5, the case of forming the upper electrode electric terminal 36 has been described, but it is also possible to further extend this when forming the wiring pattern to form the pattern of each electric terminal.

[0044]

As described above, according to the first aspect of the invention, the method of jet deposition of ultrafine particles is adopted,
It is possible to provide a method for manufacturing an ultrasonic transducer in which a resonator element can be integrally formed on a resonator without using machining such as cutting.

According to the second aspect of the present invention, the manufacturing method of jet deposition of ultrafine particles is adopted, and the piezoelectric element and the resonator sandwiching the piezoelectric element from both sides are provided with a coating layer capable of preventing water from entering and scratching. An ultrasonic vibrator manufacturing method capable of obtaining an ultrasonic vibrator can be provided.

According to the third aspect of the present invention, the ultrasonic vibrator is formed by adopting a manufacturing method called jet deposition of ultrafine particles and forming connection terminals for wiring required for driving the ultrasonic vibrator. It is possible to provide a method of manufacturing an ultrasonic transducer in which the constituent piezoelectric elements are not damaged by heat or the like during wiring.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of the present invention.

FIG. 2 is a conceptual diagram of the present invention.

FIG. 3 is a conceptual diagram of the present invention.

FIG. 4 is a side view showing a processing process according to the first embodiment of the present invention.

FIG. 5 is a side view showing the processing process of the first embodiment.

FIG. 6 is a side view showing the processing process of the first embodiment.

FIG. 7 is a side view showing the processing process of the first embodiment.

FIG. 8 is a side view of the ultrasonic oscillator (before forming the resonator element) according to the first embodiment.

FIG. 9 is a side view showing a processing process of the ultrasonic transducer having the resonator element according to the first embodiment.

FIG. 10 is a side view showing a modified example of the first embodiment.

FIG. 11 is a perspective view showing a process of forming a coating layer according to the second embodiment of the present invention.

FIG. 12 is a perspective view showing a processing process of the ultrasonic transducer according to the third embodiment of the present invention.

FIG. 13 is a perspective view showing a processing process of the ultrasonic transducer of the third embodiment.

FIG. 14 is a perspective view showing a processing process of the ultrasonic transducer of the third embodiment.

FIG. 15 is a perspective view showing a processing process of the ultrasonic transducer of the third embodiment.

FIG. 16 is a perspective view showing a processing process of the ultrasonic transducer of the third embodiment.

FIG. 17 is a perspective view showing an ultrasonic transducer according to a third embodiment.

FIG. 18 is a side view showing a conventional example.

FIG. 19 is a side view showing a conventional example.

[Explanation of symbols]

1 Ultra fine particles 2 Ultrafine particle generation chamber 3 carrier tubes 4 Carrier gas 5 nozzles 6 substrate 7 membranes 11 Ultrasonic transducer 11A ultrasonic transducer 12 nozzles 13 nozzles 14 nozzles 16 Lower electrode 17 Piezoelectric thin film 18 Upper electrode 19 Ultra fine particles 20 ultra fine particles 21 Ultra fine particles 22 Upper resonator 23 nozzles 24 Ultra fine particles 25 Lower resonator 28 lead wire 29 lead wire 32 nozzles 34 coating layer 35 Electrical terminal for lower electrode 36 Electrical terminal for upper electrode 37 Wiring pattern 38 Vibration piece 39 nozzles 40 ultra fine particles 41 Sliding member 43 Ultra fine particles 45 Lower electrode insulation band 46 nozzles 47 arrow 48 wiring patterns 49 Ultrafine particles 50 nozzles

Continued front page    (72) Inventor Takenao Fujimura             2-43 Hatagaya, Shibuya-ku, Tokyo Ori             Inside Npus Optical Industry Co., Ltd. (72) Inventor Katsuhiro Wakabayashi             2-43 Hatagaya, Shibuya-ku, Tokyo Ori             Inside Npus Optical Industry Co., Ltd. F-term (reference) 5D019 BB00 BB15

Claims (3)

[Claims] 1. A method of manufacturing an ultrasonic vibrator, comprising a piezoelectric element and a resonator sandwiching the piezoelectric element from both sides as constituent members, wherein ultrafine particles are jetted and deposited on the resonator sandwiching the piezoelectric element to vibrate. A method of manufacturing an ultrasonic transducer, comprising forming a piece. 2. A method for manufacturing an ultrasonic vibrator, comprising a piezoelectric element and a resonator sandwiching the piezoelectric element from both sides as a constituent member, wherein the piezoelectric element and the resonator sandwiching the piezoelectric element from both sides are formed. A method for manufacturing an ultrasonic vibrator, characterized in that a coating layer is formed by spray depositing ultrafine particles of an insulating material or a metal on these side surfaces. 3. A method of manufacturing an ultrasonic vibrator, comprising a piezoelectric element and a resonator made of an insulating material sandwiching the piezoelectric element from both sides as constituent members, wherein a connecting terminal is formed on the resonator, and the connecting terminal is formed. A method for manufacturing an ultrasonic vibrator, characterized in that a terminal is connected to an upper electrode and a lower electrode of a piezoelectric element by a conductor layer formed by jet deposition of ultrafine particles.