JPH10328631A - Ultrasonic cleaning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cause a device to make a matching of impedance between a vibrator and an ultrasonic wave oscillator surely and easily. SOLUTION: The ultrasonic cleaning device, which cleans objects to be cleaned by imparting ultrasonic wave vibration to cleaning liquid, includes a device body 11 to which cleaning liquid is supplied, a vibrator 24 attached to a vibration plate 21 provided in the body 11, an ultrasonic wave oscillator 31 which is connected electrically to the vibrator 24 and drives it to effect ultrasonic wave vibration, and a coil 28 and a capacitor 32 which are provided between the oscillator 31 and the vibrator 24 to make a matching of impedance between the vibrator 24 and the oscillator 31. In this case, the coil, 28 is provided in the body 11 and an electrode 29 is spidably mounted to the winding of the coil 28 and one end of the coil 28 is connected to the oscillator 31 through the electrode 29 and the other end thereof is connected to the oscillator 31 through the vibrator 24.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[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 an object to be cleaned such as a glass substrate for a liquid crystal or a semiconductor wafer with high cleanliness. As a method of cleaning the object to be cleaned, there are a dip method in which a plurality of objects to be cleaned are immersed in a cleaning liquid, and a single-wafer method in which the cleaning liquid is sprayed toward the object to be cleaned to wash one by one. In addition to obtaining high cleanliness, a single-wafer method which is advantageous in terms of cost is often 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.

The vibration applied to the cleaning liquid has conventionally been 20 to 50 k.
Hz, but recently 600-2000 kHz
An ultrasonic cleaning device that applies a sound wave in the ultra-ultrasonic band of about z has been developed.

The ultrasonic cleaning apparatus has an apparatus main body, and the apparatus main body is provided with a diaphragm on which a vibrator is attached. An ultrasonic oscillator is connected to the vibrator. The ultrasonic oscillator outputs power of a predetermined frequency and applies the power to the vibrator. Accordingly, the vibrator vibrates ultrasonically, and the vibrating plate is linked to the ultrasonic vibration, and the vibrating plate applies ultrasonic vibration to the cleaning liquid.

According to the ultrasonic cleaning apparatus having the above structure, for example, the bonding state between the diaphragm and the vibrator is not constant,
Due to the fact that the vibrator has unique characteristics, it is inevitable that the impedance of operating the vibrator of each ultrasonic cleaning apparatus in an optimum state with low power consumption and high efficiency is varied. Therefore, a coil and a capacitor are provided in a matching circuit provided with the vibrator, and impedance matching between the ultrasonic oscillator and the vibrator is performed by using the coil and the capacitor.

Conventionally, the impedance between the ultrasonic oscillator and the vibrator is
In order to perform dance matching, a plurality of coils having different impedances are prepared in advance, each coil is sequentially incorporated into a matching circuit, and a matching state is measured. It has been practiced to use a coil having a high inductance.

However, if impedance matching is performed in this way, a plurality of coils having different impedances must be prepared, which is not only uneconomical, but also requires an ultrasonic cleaning device. Since the most suitable impedance coil must be selected and mounted for each case, the work may be troublesome, and furthermore, fine adjustment cannot be performed simply by replacing the coil.

[0009]

As described above, conventionally, it has been customary to select and mount a coil having an inductance suitable for each ultrasonic cleaning apparatus. Therefore, a plurality of coils having different inductances are prepared. In addition, since it is necessary to select an optimum one, the operation is not easy, and fine adjustment is difficult.

The present invention has been made based on the above circumstances, and an object of the present invention is to provide an ultrasonic cleaning apparatus capable of performing impedance matching by using a coil provided in the ultrasonic cleaning apparatus in advance. To provide.

[0011]

According to the first aspect of the present invention, there is provided an ultrasonic cleaning apparatus for applying an ultrasonic vibration to a cleaning liquid to clean an object to be cleaned, and an apparatus main body to which the cleaning liquid is supplied, and the apparatus main body. A vibrator attached to a vibrating plate provided in the main body, an ultrasonic oscillator electrically connected to the vibrator and driving the vibrator to ultrasonically vibrate; and an ultrasonic oscillator and the vibrator. A coil and a capacitor are provided between the vibrator and the ultrasonic oscillator for impedance matching between the vibrator and the ultrasonic oscillator. The coil is provided in the main body of the apparatus. It is slidably provided, and one end of the coil is connected to the ultrasonic oscillator via the electrode, and the other end is connected to the ultrasonic oscillator via the vibrator.

According to the first aspect of the present invention, when the electrode provided on the coil is slid, the inductance in the circuit of the coil can be changed. Therefore, a plurality of coils having different inductances are not prepared.
Impedance matching between the ultrasonic oscillator and the vibrator can be achieved.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. The ultrasonic cleaning apparatus of the present invention shown in FIG. The apparatus main body 11 is joined and fixed in a liquid-tight manner to an upper member 13 having a concave portion 12 with an open upper surface formed along the longitudinal direction and a lower surface of the upper member 13 through a first seal member 14. The lower member 15 forms an elongated prism.

A fitting hole 16 is formed in the widthwise central portion of the lower wall of the upper member 13 along the longitudinal direction, and the fitting hole 16 is formed in the widthwise central portion of the upper surface of the lower member 15. A convex portion 17 to be fitted is formed.

A space 18 having one end opened to the upper surface and the other end opened to the lower surface is formed along the longitudinal direction at the center in the width direction of the lower member 15 where the convex portion 17 is formed. . The cross-sectional shape of the space 18 is tapered such that the width decreases from one end (upper end) to the other end (lower end), and the lower end opening is a narrow nozzle opening 19. .

The open upper end of the space 18 is closed in a liquid-tight manner by a vibrating plate 21 formed in a rectangular plate shape with tantalum, titanium or an alloy thereof. 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 screws 20. Thereby, the upper end opening of the space 18 is liquid-tightly closed.

A central portion in the width direction of the upper surface of the diaphragm 21;
That is, the vibrator 24 is attached to a portion corresponding to the space 18 along the longitudinal direction of the diaphragm 21. A power supply plate 25 is attached to the press plate 23 via a holding member 26 above the vibration plate 21. The power supply plate 25 is provided with a leaf spring-like contact 27 that is in elastic contact with the vibrator 24.

The power supply plate 25 is provided with a coil 28 having one end (lower end) electrically connected thereto. This coil 2
At the other end (upper end side) of the electrode 8, an electrode 29 is provided so as to be slidable and fixable at an arbitrary sliding position.

For example, as shown in FIG. 2, the electrode 29 has a through hole 29 through which one end of the winding of the coil 28 is inserted.
and a fixing screw 29c screwed into a screw hole 29d formed in the slide member 29b so as to intersect with the through hole 29a. The fixing screw 29c is loosened. The slide member 29
b is slid along the winding, and the fixing screw 29c is tightened at a predetermined position, whereby the electrode 29
Can be fixed at an arbitrary position while being electrically connected to the coil 28.

One end of a first cable 30a of a coaxial cable 30 having a resistance of 50Ω, for example, is connected to the slide member 29b of the electrode 29. That is, one end of the coil 28 is connected to one end of the first cable 30a via the electrode 29. The other end of the coil 28 is
And a contact 27 to one electrode of the vibrator 24.

The other electrode of the vibrator 24 is
The holding plate 23 is electrically connected to the holding plate 23, and one end of the second cable 30b of the coaxial cable 30 is connected to the holding plate 23. The other ends of these cables 30a and 30b are connected to an ultrasonic oscillator 31 for driving the vibrator 24 to perform ultrasonic vibration. In addition, the device main body 11 has the first
A variable condesin 32 connected between the cable 30a and the second cable 30b is provided to form a matching circuit 33 for ultrasonically vibrating the vibrator 24 as shown in FIG. ing. That is, the matching circuit 33
And the ultrasonic oscillator 31 are connected by a coaxial cable 30.

Therefore, by sliding the electrode 29 to adjust the inductance of the coil 28 in the matching circuit 33 or the reactance of the variable capacitor 32, the ultrasonic oscillator 31 and the vibrator 24 are adjusted.
Impedance matching can be performed.

In the lower member 15 of the apparatus main body 11, a pair of supply paths 34 located on both sides in the width direction of the space 18 are formed so as to penetrate in the longitudinal direction. A supply source (not shown) is connected to both ends of the supply path 34 via a tube (not shown) to supply a cleaning liquid such as pure water or a chemical solution.

Each of the pair of supply paths 34 is provided with a plurality of ejection paths 35 (only one is shown), one end of which is communicated. That is, the ejection path 35 is formed at a portion where the upper member 13 and the lower member 15 of the apparatus main body 11 are joined,
The other end is opened so as to communicate with a portion of the inner bottom surface of the concave portion 12 of the upper member 13 covered by the vibration plate 21, that is, the upper end side of the space 18. A plurality of the ejection paths 35 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.

The ultrasonic oscillator 31 has a frequency synthesizer 41 as shown in FIG. The frequency synthesizer 41 outputs power of a predetermined frequency, and the frequency is controlled by the CPU 42. In this embodiment, the frequency from the frequency synthesizer 41 is 1590 kHz as the first frequency, 1600 kHz as the second frequency, and 1610 kHz as the third frequency.
The conversion is controlled to z. That is, the CPU 42 sequentially converts the frequency of the power output from the frequency synthesizer 41 into the first to third frequencies at predetermined time intervals.

The power of a predetermined frequency output from the frequency synthesizer 41 is amplified by a high-frequency power amplifier 43, and a CM coupler (pass-through power meter) for monitoring the voltage and current of the coaxial cable 30 having a resistance of 50Ω. The output is monitored at 44 and output to the matching circuit 33.

The CM coupler 44 can check the matching between the ultrasonic oscillator 31 and the vibrator 24 according to the following principle. That is, the measured voltage is represented by C
The partial pressure is set to V _{v in} phase with the partial pressure. Mutual induction M bonds in the secondary circuit sucrose - DOO conditions, i.e. by passing a secondary current to a sufficiently low resistance current transformer, making the voltage V _i of the current having the same phase. And, if you check the matching is checked by whether V _v -V _i is 0. In other words, the fact that the phases match when V / I = 50Ω means that the matching is achieved.

Next, the case where the ultrasonic cleaning apparatus having the above configuration is used will be described. First, impedance matching between the ultrasonic oscillator 31 and the vibrator 24 is performed in order to efficiently vibrate the vibrator 24 before actually using the ultrasonic cleaning apparatus having the above configuration. That is, the ultrasonic oscillator 31 is operated to cause the oscillator 24 to oscillate ultrasonically, and at this time, the ultrasonic oscillator 31 and the oscillator 2
4 is measured by the CM coupler 44 to determine whether or not impedance matching with 4 is achieved.

If the matching is not achieved, the electrode 29 provided on the winding of the coil 28 is slid along the winding to adjust the inductance in the matching circuit 33 and the variable capacitor 32 is adjusted. Similarly, the reactance in the matching circuit 33 is adjusted, and the impedance between the ultrasonic oscillator 31 and the vibrator 24 is adjusted.
Match the dance.

The adjustment of the inductance of the coil 28 simply involves sliding the electrode 29 along the winding. That is, a plurality of coils having different inductances are prepared as in the related art, and each coil is sequentially incorporated into the matching circuit 33 to measure a matching state, and a coil having an optimum inductance is used for the matching circuit 33. You don't have to.

Therefore, not only can the operation of matching the impedance be performed easily, but also the inductance can be finely adjusted by the simple operation of sliding the electrode 29. Therefore, the ultrasonic oscillator 31 and the vibrator 24 can be adjusted with high accuracy. Can be matched.

Further, the coil 28 and the variable capacitor 32 are provided in the apparatus main body 11. Therefore, even if the vibrator 24 provided in each device main body 11 has a unique inductance and reactance,
Can be matched to the ultrasonic oscillator 31 connected to the device main body 11 and the ultrasonic oscillator 31
Can be provided with compatibility.

When the impedances of the vibrator 24 and the ultrasonic oscillator 31 are matched in this way, the cleaning liquid is supplied from the pair of supply paths 34 to the space 18 via the ejection path 35. The cleaning liquid supplied to the space 18 is subjected to ultrasonic vibration by the vibration plate 21 that ultrasonically vibrates together with the vibrator 24, and is ejected from the nozzle port 19. Accordingly, the object to be cleaned, which is disposed to face the nozzle port 19, can be ultrasonically cleaned by the cleaning liquid.

Since the transducer 24 and the ultrasonic oscillator 31 are impedance-matched, the transducer 24 can be efficiently ultrasonically vibrated. That is, since the power consumption can be minimized, the running cost of the ultrasonic oscillator 31 can be reduced.

The frequency of the power output from the frequency synthesizer 41 of the ultrasonic oscillator 31 is converted into a first frequency, a second frequency and a third frequency at predetermined time intervals by a signal from the CPU 42. The operation time at each frequency is set to be longer than the operation time at the other frequency, for example, when the cleaning effect at the first frequency is higher than that at the other frequency. To increase the overall cleaning effect.

As described above, the vibrator 24 vibrates while changing the frequency every predetermined time. Therefore, the vibration wave generated in the space 18 formed in the apparatus main body 11 according to the change of the vibration frequency also changes as shown by ac in FIG.

When the vibration wave changes, the position of the antinode S of each vibration wave in the space 18 also changes. Therefore, even if the bubble B adheres to the wall surface of the space 18, the bubble B hits the antinode S of any of the vibration waves a to c, and is separated from the wall before growing by the antinode S. Out of the nozzle port 19.

That is, even if air bubbles adhere to the inner surface of the space 18, the air bubbles B grow and float and are removed before adhering to the lower surface of the vibration plate 21. When the transmission efficiency of the ultrasonic vibration is reduced and the grown bubbles B adhere to the vibration plate 21, it is possible to prevent the cleaning liquid from coming into contact with the portion and prevent the temperature from rising abnormally.

[0040]

As described above, according to the first aspect of the present invention, in an ultrasonic cleaning apparatus in which a vibrator is driven by an ultrasonic oscillator, a coil is provided in the apparatus, and an electrode is slid on the winding of the coil. By freely arranging the electrodes and sliding the electrodes, the inductance of the coil is changed to obtain impedance matching between the ultrasonic oscillator and the vibrator.

For this reason, the impedance matching between the ultrasonic oscillator and the vibrator can be obtained only by sliding the electrodes without preparing a plurality of coils having different inductances as in the prior art. Work can be performed easily. In addition, since the inductance of the coil can be continuously changed by sliding the electrodes, fine adjustment of the impedance matching is possible. Further, by providing the coil in the apparatus main body, there is an advantage that compatibility between the ultrasonic oscillator and the apparatus main body can be provided.

[Brief description of the drawings]

FIG. 1 is a sectional view of a schematic configuration of an ultrasonic cleaning apparatus according to an embodiment of the present invention.

FIG. 2 is a sectional view of an electrode provided in the coil.

FIG. 3 is an electric circuit diagram.

FIG. 4 is an explanatory diagram when vibrations of different frequencies are similarly applied to the cleaning liquid.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... Device main body 24 ... Vibrator 21 ... Vibration plate 28 ... Coil 29 ... Electrode 31 ... Ultrasonic oscillator 32 ... Capacitor

Claims (1)

[Claims] 1. An ultrasonic cleaning apparatus for applying an ultrasonic vibration to a cleaning liquid to clean an object to be cleaned, comprising: an apparatus main body to which the cleaning liquid is supplied; and a vibration plate provided on the apparatus main body. A vibrator, an ultrasonic oscillator electrically connected to the vibrator and driving the vibrator to ultrasonically vibrate; and an ultrasonic oscillator provided between the ultrasonic oscillator and the vibrator. A coil and a capacitor for impedance matching with the sound wave oscillator. The coil is provided in the main body of the apparatus, and an electrode is slidably provided on a winding of the coil. An ultrasonic cleaning apparatus, wherein one end is connected to the ultrasonic oscillator via the electrode, and the other end is connected to the ultrasonic oscillator via the vibrator.