JPH1099805A - Ultrasonic vibration generator and ultrasonic cleaning apparatus using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the resonance effect of a diaphragm by specifying the thickness of the diaphragm in a machine in which a vibrator is attached to the diaphragm, the vibrator is driven by an ultrasonic wave generator. SOLUTION: In an ultrasonic cleaning apparatus using an ultrasonic vibrator which gives ultrasonic vibration to cleaning liquid for cleaning semiconductor wafers etc., the cleaning liquid is supplied to a pair of supply routes 31, a vibrator 24 is driven by an ultrasonic vibration generator to vibrate a diaphragm 21 ultrasonically. The cleaning liquid supplied to the supply route 31 is distributed into ejection routes 32 to be ejected from the other end openings of the ejection routes 32 toward the diaphragm 21. When the cleaning liquid ejected from each ejection route 32 collides with the lower surface of the diaphragm 21, the ultrasonic vibration is propagated to the liquid. The thickness of the diaphragm 21 is set up to be less than 0.1mm to obtain a high effect of resonance with the vibrator 24. In this way, the diaphragm 21 is made to resonate with the vibrator 24, the attenuation of the vibration is restrained to be able to give strong ultrasonic vibration to the cleaning liquid.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic vibration device for applying ultrasonic vibration to a cleaning liquid for cleaning an object to be cleaned and an ultrasonic cleaning device using the same.

[0002]

2. Description of the Related Art For example, in a liquid crystal manufacturing apparatus or a semiconductor manufacturing apparatus, there is a process required to clean a liquid crystal glass substrate or a semiconductor wafer as a cleaning object with high cleanliness. As a method of cleaning such an object to be cleaned, there are a dip method in which a plurality of substrates to be cleaned are immersed in a cleaning liquid, and a single-wafer method in which a cleaning liquid is sprayed toward an object to be cleaned to wash one by one. In recent years, a single-wafer method which is advantageous in terms of cost while being able to obtain high cleanliness has been increasingly used.

[0003] As one of the single-wafer methods, a cleaning method has been put to practical use in which ultrasonic vibration is applied to a cleaning liquid sprayed on a cleaning object to thereby efficiently remove fine particles from the cleaning object by vibrating action. ing.

In a cleaning method for applying ultrasonic vibration to a cleaning liquid, an ultrasonic wave of about 20 to 50 kHz has been conventionally used, but recently, an ultrasonic cleaning apparatus using a sound wave in an ultra-ultrasonic band of about 600 to 2000 kHz. Is being developed.

When the cleaning liquid to which the ultrasonic vibration is applied is sprayed onto the object to be cleaned, the action of the ultrasonic vibration reduces the bonding force of the fine particles adhered to the object to be cleaned. As a result, the cleaning effect can be improved.

The conventional ultrasonic cleaning apparatus has an elongated apparatus main body 1 as shown in FIG. A space 2 is formed in the apparatus main body 1 so as to penetrate in the thickness direction of the main body 1 and to extend along the longitudinal direction. The space portion 2 is formed in a tapered shape that becomes narrower in width from the upper end to the lower end, and the lower end is a nozzle port 3 opened on the lower surface of the apparatus main body 1.

The upper end opening of the space 2 is closed by a diaphragm 5 made of a metal plate such as tantalum via a seal material 4. A plurality of elongated rectangular vibrators 6 (only one is shown) are attached to the upper surface of the diaphragm 5 at predetermined intervals along a portion corresponding to the upper end opening of the space 2. The vibrator 6 is driven by an ultrasonic oscillator (not shown). Since the vibrator 6 is ultrasonically vibrated by the ultrasonic oscillator, the vibration plate 5 is also vibrated by the ultrasonic vibration. That is, the vibration plate 5, the vibrator 6, and the ultrasonic oscillator constitute an ultrasonic vibration device.

On both sides of the space portion 2 of the apparatus main body 1, supply paths 8 are formed penetrating along the longitudinal direction. A pair of supply passages 8 for cleaning liquid (not shown) are connected to both ends of the pair of supply paths 8, and the cleaning liquid is supplied by the supply pipes.

Further, a plurality of ejection paths 9 having one end communicating with the supply path 8 and the other end communicating with the space 2 are formed at predetermined intervals along the longitudinal direction of the apparatus main body 1. Is formed. That is, the other end of the ejection path 9 is open to face the diaphragm 5. The ejection path 9 has a sufficiently smaller inner diameter than the supply path 8.

The cleaning liquid supplied to the supply passage 8 is almost equally diverted to the plurality of ejection passages 9 and is ejected from the opening at the other end toward the lower surface of the vibration plate 5. Ultrasonic vibration is applied by the ultrasonic vibrator 6. The cleaning liquid to which the ultrasonic vibration has been applied is ejected from the nozzle port 3 of the space 2 toward the object to be cleaned (not shown). Thereby, the object to be cleaned can be cleaned with the cleaning liquid to which the ultrasonic vibration is applied.

By the way, in the ultrasonic cleaning apparatus having such a configuration, the vibration plate 5 is usually formed of a metal such as tantalum, titanium, or an alloy thereof, and when the ultrasonic vibrator 6 oscillates, It vibrates in resonance with the vibration of the vibrator 6. However,
If the thickness of the diaphragm 5 exceeds 1.5 mm, the resonance efficiency with the vibrator 6 may decrease, so the thickness of the diaphragm 5 was 0.1 to 1.5 mm.

However, when the thickness of the diaphragm 5 is extremely reduced, its strength is greatly reduced. Therefore, when vibrating repeatedly, it may be damaged early or the vibrator 6 attached to the vibrating plate 5 may be peeled off, which is not practical. In practice, a diaphragm 5 having a thickness of 0.1 mm or more that can withstand long-term use even if the resonance efficiency is reduced has been used.

[0013]

As described above, since the thickness of the diaphragm is conventionally set to 0.1 mm or more, the resonance efficiency is reduced even if the strength is obtained without damage at an early stage. In some cases, the vibration was attenuated.

It is an object of the present invention to reduce the thickness of the diaphragm to 0.1.
It is an object of the present invention to provide an ultrasonic vibration device and an ultrasonic cleaning device using the ultrasonic vibration device in which the resonance efficiency is improved by setting the diameter to less than mm.

Another object of the present invention is to provide an ultrasonic vibrating apparatus and an ultrasonic cleaning apparatus using the ultrasonic vibrating apparatus, wherein the strength of the vibrating plate does not decrease even when the thickness of the vibrating plate is 0.1 mm or less. Is to do.

[0016]

According to a first aspect of the present invention, there is provided an ultrasonic vibration device in which a vibrator is attached to a vibrating plate and the vibrator is driven by an ultrasonic oscillator. It is characterized by being less than 0.1 mm.

According to a second aspect of the present invention, in the ultrasonic vibration device in which a vibrator is attached to a vibrating plate and the vibrator is driven by an ultrasonic oscillator, the vibrating plate has a thickness of less than 0.1 mm. In addition, a portion deviated from the vibrator has a structure reinforced by a reinforcing member.

According to a third aspect of the present invention, there is provided an ultrasonic cleaning apparatus provided with an ultrasonic vibration device for applying ultrasonic vibration to a cleaning liquid for cleaning an object to be cleaned, wherein the ultrasonic vibration device is the first or the second invention. A configuration according to claim 2 is characterized.

According to the first aspect of the present invention, by setting the thickness of the diaphragm to less than 0.1 mm, the resonance efficiency with the vibrator can be improved and the vibration of the diaphragm can be strengthened. According to the second aspect of the present invention, the diaphragm is made extremely thin to improve the resonance efficiency, and even if the vibration of the diaphragm is strong, the diaphragm is reinforced by the reinforcing member, thereby preventing early damage. Is done.

According to the third aspect of the present invention, by using the ultrasonic vibration device of the eleventh or the second aspect in the ultrasonic cleaning device, it is possible to vibrate, and thereby to reliably generate an ultrasonic vibration that is strong against the cleaning liquid via the vibration plate. , And the ultrasonic cleaning device can be used for a long time without maintenance.

[0021]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
This will be described with reference to FIGS. The ultrasonic cleaning apparatus of the present invention shown in FIG. This device body 1
Reference numeral 1 denotes an upper member 13 in which a concave portion 12 having an open upper surface is formed along the longitudinal direction thereof, and a lower member liquid-tightly joined and fixed to a lower surface of the upper member 13 via a first seal member 14. Fifteen
And are formed in an elongated prismatic shape.

A fitting hole 16 is formed in the lower wall of the upper member 13 along the longitudinal direction thereof, and a convex portion which fits into the fitting hole 16 is formed in the center of the upper surface of the lower member 15 in the width direction. Part 1
7 are formed.

A space 18 having one end opened on the upper surface and the other end opened on the lower surface is formed along the longitudinal direction of the lower member 15 at the center in the width direction where the convex portion 17 is formed. I have. The sectional shape of the space 18 is one end (upper end)
Has a tapered shape in which the width dimension is reduced from the bottom to the other end (lower end).
It is 9.

The open upper end of the space 18 is liquid-tightly closed by a rectangular diaphragm 21. That is, the diaphragm 21 is joined to the inner bottom surface of the concave portion 12 of the upper member 13 through the frame-shaped second seal member 22 having a predetermined thickness at the lower peripheral portion.

A frame-like holding plate 23 is joined to the upper surface of the vibration plate 21, and is fixed to the upper member 13 by bolts 33. Thereby, the upper end opening of the space 18 is airtightly closed.

A central portion in the width direction of the upper surface of the diaphragm 21;
That is, as shown in FIG. 1, a plurality of vibrators 24 are adhered and fixed to a portion corresponding to the space portion 18 by closely contacting adjacent side surfaces along the longitudinal direction. Electrodes 24 each made of a metal film such as Ag are formed on the upper and lower surfaces of the vibrator 24.
a and 24b are formed.

The vibrating plate 21 is made of a high-tensile metal such as tantalum, titanium, or an alloy thereof, and the thickness T is set to less than 0.1 mm where the resonance phenomenon with the vibrator 24 is small.

As shown in FIG. 2, the vibrator 24 is joined to a substantially central portion of the upper surface of the vibrating plate 21, and upper reinforcing plates 41a are provided on both sides of the vibrator 24 with the vibrating plate 21 interposed therebetween. And the lower reinforcing plate 41b are bonded to each other via an adhesive or a seal material, and are integrally connected to the diaphragm 21 by screws 42. As a result, the portion of the diaphragm 21 where the vibrator 24 is provided has a thickness of less than 0.1 mm, which has high resonance efficiency with the vibrator 24, and the other portions are reinforced by the upper and lower reinforcing plates 41a and 41b. It has a thickness that is difficult to damage. The thickness of each of the reinforcing plates 41 a and 41 b is set sufficiently thicker than the diaphragm 21. The diaphragm 21 is joined to the inner bottom surface of the concave portion 12 of the upper member 13 via the reinforcing members 41a and 41b, and is fixed to the upper member 13 by bolts 33 via the holding plate 23.

As shown in FIG. 3, above the vibration plate 21, a power supply plate 25 is attached to the holding plate 23 via a holding member 26. The power supply plate 25 includes the vibrator 2
4. A contact 27 elastically in contact with the electrode 24a on the upper surface side
Is provided. A coil 28 is provided on the power supply plate 25, and the power supply plate 25, the contact 2
The power is supplied to the vibrator 24 via the. Thereby, the vibrator 24 is ultrasonically vibrated, and the vibration plate 21 is interlocked with the ultrasonic vibration.

In the lower member 15 of the apparatus main body 11, a pair of supply paths 31 located on both sides in the width direction of the space 18 are formed so as to penetrate in the longitudinal direction. This supply path 3
A supply source (not shown) is connected to both ends of the unit 1 via a tube (not shown) so as to supply a cleaning liquid such as pure water or a chemical solution.

Each of the pair of supply paths 31 is provided with a plurality of ejection paths 32 each having one end communicating therewith. That is, the ejection path 32 is provided between the upper member 13 and the lower member 15 of the apparatus main body 11.
And the other end is opened so as to communicate with a portion covered by the diaphragm 21 on the inner bottom surface of the concave portion 12 of the upper member 13, that is, the upper end side of the space portion 18. I have.

A plurality of ejection paths 32 are formed at predetermined intervals along the longitudinal direction of the apparatus main body 11 on one side and the other side in the width direction of the space 18. Next, the operation of the ultrasonic cleaning apparatus having the above configuration will be described.

The cleaning liquid is supplied to the pair of supply paths 31, and the vibrator 24 is driven by an ultrasonic oscillator to ultrasonically vibrate the diaphragm 21. The cleaning liquid supplied to the supply path 31 is divided into a plurality of ejection paths 32 and is ejected toward the diaphragm 21 from the other end opening of the ejection path 32.

When the cleaning liquid ejected from each ejection path 32 collides with the lower surface of the vibrating plate 21 that vibrates ultrasonically, the ultrasonic vibration propagates to the cleaning liquid. The cleaning liquid to which the ultrasonic vibration has propagated, that is, the cleaning liquid which is ultrasonically vibrated, flows through the space 18 as shown by the arrow in FIG. Therefore, when the object to be cleaned is disposed below the nozzle port 19, the object to be cleaned can be cleaned with the cleaning liquid to which the ultrasonic vibration is applied.

The thickness T of the vibrating plate 21 is set to a thickness of less than 0.1 mm at which the resonance efficiency with the vibrator 24 is high. Since the vibration plate 21 resonates with the vibrator 24 and the attenuation of the vibration is reduced, strong ultrasonic vibration can be applied to the cleaning liquid.

FIG. 4 shows that the thickness T is 0.05 mm and 0.0 mm.
When the diaphragm 21 of 85 mm and 0.1 mm is used, the relationship between the sound pressure of the cleaning liquid ejected from the nozzle port 19 and the output of the ultrasonic oscillator driving the ultrasonic vibrator 24 for driving the vibrator 24. 5 is a graph obtained by measuring. As can be seen from this figure, the thickness T of the diaphragm 21 is 0.1 mm.
By setting it to less than 3, a high sound pressure can be obtained, and the thinner the thickness dimension T, the higher the sound pressure.

When the thickness of the vibration plate 21 is 0.05 mm, both sides of the vibration plate 21 to which the vibrator 24 is joined are reinforced by the upper reinforcement plate 41a and the lower reinforcement plate 41b. Therefore, the portion where the vibrator 24 is provided is maintained at a high resonance efficiency with the vibrator 24 to a thickness of less than 0.1 mm, but the other portions are the reinforcing plates 41a,
The diaphragm 21 is reinforced by the vibration plate 41b.
Even if the portion provided with 4 vibrates strongly in resonance with the vibrator 24, it is prevented from being damaged early by the vibration.

Further, the reinforcing plate 41b shown in FIG.
May be applied to both sides of the portion of the diaphragm 21 where the vibrator 24 is provided. With this configuration, the vibrating plate 21 (the portion having the dimension c) in contact with the cleaning liquid is substantially reinforced by the upper and lower reinforcing plates 41a and 41b and the vibrator 24.

In this case, the width a of the upper electrode 24a is made slightly smaller than the width b of the vibrator 24 and
If the width c of the portion not reinforced by the upper and lower reinforcing plates 41a, 41b is substantially the same, the portion of the width a vibrates, so that the four corners of the vibrating member 24 attached to the diaphragm 21 are hardly peeled off. Become.

Further, by making the ends of the sides of the upper electrode 24a smaller than the ends of the sides of the vibrator 24 by about 0.5 mm, the plurality of vibrators 24 are closely attached in the longitudinal direction of the diaphragm 21. Even if it is attached, the distance between the ends of one side of each electrode 24 is about 1 mm.
Thus, a sufficient insulation distance can be secured between the electrodes.

The ultrasonic vibration is applied to the vibrator 24, for example.
When the vibration plate 21 is disposed on the upper part, the cleaning liquid is transmitted from the top to the bottom in the cleaning liquid in a divergent manner, so that the cleaning liquid jetted to the portion directly contacting the object to be cleaned is given uniform ultrasonic vibration.

That is, according to the diaphragm 21 having the above structure,
Since it has a high resonance efficiency with the vibrator 24 and a strength that does not cause early damage, it is possible to reliably apply strong vibration to the cleaning liquid supplied to the supply unit 8 of the apparatus main body 11 over a long period of time. Can be.

Although the above embodiment has been described with reference to the upper reinforcing plate 41a and the lower reinforcing plate 41b, either one of them may be used.
FIG. 5 shows another embodiment of the present invention. In this embodiment, a step portion 51 is formed on one end side in the width direction of an upper reinforcing plate 41a provided on the upper surface side of the vibration plate 21, and the step portion 51 presses and holds the end portion in the width direction of the vibrator 24. The upper reinforcing plate 41a is connected to the lower reinforcing plate 41b by screws 42.

One of the electrodes 24a provided on the vibrator 24 is provided only at the center of the upper surface of the diaphragm 21 in the width direction as shown by the dimension e, and the other electrode 24b is provided on the lower and upper surfaces of the vibrator 24. Are provided over both sides in the width direction. Therefore, the step portion 51 of the upper reinforcing plate 41a contacts only the other electrode 24b and does not contact the one electrode 24a. The dimension e is set substantially equal to the distance f between the pair of lower reinforcing plates 41b.

That is, according to such a configuration, even if the upper reinforcing plate 41a is made of resin, the other electrode 24b extends around the side portion of the vibrator 24 and extends to the upper surface. Can be easily connected.

Further, according to the present invention, not only a single-wafer ultrasonic cleaning apparatus for spraying a cleaning liquid onto a cleaning object but also a plurality of cleaning objects are immersed in a cleaning tank storing the cleaning liquid. It is also possible to apply the present invention to a dip type ultrasonic cleaning apparatus that applies ultrasonic vibration to the cleaning liquid and cleans an object to be cleaned by using an ultrasonic vibration apparatus disposed at the bottom of a tank or the like.

[0047]

According to the first aspect of the present invention, the thickness of the diaphragm to which the vibrator is attached is less than 0.1 mm, which is lower than 0.1 mm. The resonance efficiency can be increased.

According to the second aspect of the present invention, the thickness of the vibration plate to which the vibrator is attached is set to less than 0.1 mm, and a portion of the vibrating plate which is off the vibrator is reinforced by the reinforcing member. I made it.

As a result, the thickness of the diaphragm can be made sufficiently thin so that the resonance efficiency with the vibrator can be sufficiently increased, and at the same time, the strength is reinforced by the reinforcing member, thereby preventing early damage. it can.

According to the third aspect of the present invention, by using the ultrasonic vibration device of the first or second aspect for the ultrasonic cleaning device, it is possible to reliably apply strong ultrasonic vibration to the cleaning liquid, Can be used without the need for long-term maintenance.

[Brief description of the drawings]

FIG. 1 is an enlarged plan view of a vibrator mounting structure according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG. 1;

FIG. 3 is a longitudinal sectional view of the ultrasonic cleaning apparatus.

FIG. 4 is a graph showing the relationship between the sound pressure and the output of an ultrasonic oscillator when the thickness of the diaphragm is changed.

FIG. 5 is an enlarged cross-sectional view of an ultrasonic transducer mounting structure according to another embodiment of the present invention.

FIG. 6 is a longitudinal sectional view of a conventional ultrasonic cleaning device.

[Explanation of symbols]

 21: diaphragm 24: vibrator 41a, 41b: reinforcing member

Claims (3)

[Claims] 1. An ultrasonic vibration device in which a vibrator is attached to a vibrating plate and the vibrator is driven by an ultrasonic oscillator, wherein the vibrating plate has a thickness of less than 0.1 mm. Ultrasonic vibration device. 2. An ultrasonic vibration device in which a vibrator is attached to a vibrating plate and the vibrator is driven by an ultrasonic oscillator, wherein the vibrating plate has a thickness of less than 0.1 mm and the vibrator has a thickness of less than 0.1 mm. An ultrasonic vibrating device characterized in that a portion deviated from the structure has a structure reinforced by a reinforcing member. 3. An ultrasonic cleaning device provided with an ultrasonic vibration device for applying ultrasonic vibration to a cleaning liquid for cleaning an object to be cleaned, wherein the ultrasonic vibration device is according to claim 1 or 2. An ultrasonic cleaning apparatus characterized by having a configuration as described above.