JPH1133507A - Ultrasonic cleaning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ultrasonic cleaning device in which bubbles contained in cleaning liquid are prevented from being grown and stuck to a diaphragm. SOLUTION: The ultrasonic cleaning device, in which ultrasonic vibration is given to cleaning liquid for cleaning material to be cleaned, is equipped with the body 1 forming a flow path 5 supplying cleaning liquid, a diaphragm 9 formed by facing the flow path 5, a vibrator 19 which is stuck to the diaphragm 9 and makes the diaphragm to ultrasonic vibration and a small diameter hole or a vibrator used as a vibration generation means which vibrates the body 1 and inhibits bubbles contained in cleaning liquid from adhering and remaining in the part of the body 1 coming into contact with 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 cleaning apparatus for applying ultrasonic vibration to a cleaning liquid for cleaning an object to be cleaned.

[0002]

2. Description of the Related Art For example, a liquid crystal manufacturing apparatus or a semiconductor manufacturing apparatus has a step of cleaning a glass substrate for liquid crystal or a semiconductor wafer as an object to be cleaned with high cleanliness. As a method of cleaning such an 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 a cleaning liquid is sprayed toward the 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 in which ultrasonic vibration is applied to a cleaning liquid sprayed toward a cleaning object to thereby remove fine particles efficiently from the cleaning object by vibrating action is practically used. Has been

In the cleaning method of applying ultrasonic vibration to the cleaning liquid, ultrasonic waves of about 20 to 50 kHz have been used in the past, but recently, ultrasonic waves in the ultra-ultrasonic band of about 600 to 3000 kHz have been used. Have been.

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.

Generally, an ultrasonic cleaning apparatus used for ultrasonic cleaning has a main body. The main body is formed with a flow path through which the cleaning liquid flows. The front end (lower end) of this flow path is a nozzle port opened on the lower end surface of the main body, and the rear end side (upper end side) is closed in a liquid-tight manner by a diaphragm. A vibrator driven by an ultrasonic oscillator is attached to the vibrating plate, and the vibrator is driven to vibrate the vibrating plate to apply ultrasonic vibration to the cleaning liquid flowing through the flow path. It is supposed to.

Therefore, if the object to be cleaned is arranged opposite to the nozzle port, the object to be cleaned can be cleaned with the cleaning liquid to which ultrasonic vibration is applied. The cleaning liquid is supplied to the flow path of the main body through a supply pipe. An on-off valve is provided in the supply pipe, and cavitation is generated by opening and closing the on-off valve. When the supply pipe is bent, pulsation occurs in the cleaning liquid flowing through the supply pipe. For this reason, bubbles may enter the cleaning liquid due to the cavitation or pulsation.

The air bubbles that have entered the cleaning liquid adhere to the flow path formed in the main body and grow gradually. If the buoyancy of the bubbles is greater than the flow rate of the cleaning liquid, the bubbles may float up and adhere to the diaphragm provided at the upper end of the flow path.

Then, the cleaning liquid does not come into contact with the portion of the vibration plate to which the air bubbles have adhered, so that the portion is ultrasonically vibrated without being cooled by the cleaning liquid. If the diaphragm is partially cooked, the temperature in that part will rise significantly compared to other parts,
Inducing thermal deformation of the diaphragm or transmitting the heat to the vibrator,
The oscillator may be damaged.

[0010]

As described above, when the cleaning liquid containing air bubbles is supplied to the main body, the air bubbles do not flow together with the cleaning liquid, but adhere to the inner surface of the flow path of the main body and gradually grow. It may float and adhere to the diaphragm.

As a result, the diaphragm vibrates ultrasonically without being partially cooled, so that the diaphragm locally rises in temperature and is damaged, or heat is applied to the vibrator attached to the diaphragm. In some cases, the transducer was damaged.

According to the present invention, there is provided an ultrasonic cleaning apparatus which prevents bubbles and vibrators from being damaged by preventing bubbles contained in a cleaning liquid from remaining in a main body and adhering to the diaphragm. Is to provide.

[0013]

According to a first aspect of the present invention, there is provided an ultrasonic cleaning apparatus for applying ultrasonic vibration to a cleaning liquid for cleaning an object to be cleaned, comprising: a main body having a flow path for supplying the cleaning liquid; A vibrating plate provided facing the flow path, a vibrator attached to the vibrating plate for ultrasonically vibrating the vibrating plate, and a vibrating main body included in the cleaning liquid at a portion of the main body where the cleaning liquid comes into contact. Vibration generating means for preventing the remaining air bubbles from adhering and remaining.

[0014] According to a second aspect of the present invention, in the first aspect of the present invention, the main body includes a nozzle orifice in which the flow path is formed;
The nozzle mouth comprises a base fixed and joined in a liquid-tight manner via an elastic sheet, and a supply passage for supplying the cleaning liquid to the flow path is formed over the base and the nozzle mouth, and The vibration generating means is characterized by comprising a small-diameter hole formed in a portion of the elastic sheet corresponding to the supply path with a smaller diameter than the supply path.

According to a third aspect of the present invention, in the first aspect of the invention, the vibration generating means comprises a vibrator provided on the main body. According to the first to third aspects of the present invention, by vibrating the main body in which the flow path of the cleaning liquid is formed by the vibration generating means, bubbles contained in the cleaning liquid are prevented from adhering and remaining on the inner surface of the flow path. can do.

According to the second aspect of the present invention, the main body is divided into a nozzle opening and a base, and these are joined in a liquid-tight manner via an elastic sheet. Since the main body is made to vibrate, it is not necessary to use a dedicated component to vibrate the main body.

According to the third aspect of the invention, since the main body is vibrated by providing the vibrator in the main body, the main body can be reliably vibrated at a desired timing.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 and 2 show a first embodiment of the present invention. The ultrasonic cleaning apparatus shown in FIG. The main body 1 is divided into a nozzle mouth 2a and a base 2b. The base 2b has the nozzle opening 2a
Is formed with a fitting hole 3 into which is fitted. Nozzle mouth 2a
An elastic sheet 4 made of rubber, synthetic resin, or the like is interposed between the joining surfaces of the base and the base 2b in order to maintain these liquid-tight states.

A channel 5 is formed in the nozzle opening 2a. The flow path 5 has a tapered shape in which the width is gradually narrowed from the upper end to the lower end, and the lower end is a nozzle port 6 opened at the lower end surface of the nozzle opening 2a.

The fitting hole 3 formed in the base 2b is open to the upper surface of the base 2b via a first step 7 and a second step 8. A diaphragm 9 is liquid-tightly joined to the second step portion 8 via a packing 11,
2 attached and fixed. Thereby, the diaphragm 9 forms a liquid-tight space 13 between the upper end side of the flow path 5 and the lower surface side of the diaphragm 9.

A main supply path 14 is formed in the nozzle opening 2a along one side of the lower end of the flow path 5 along the longitudinal direction of the nozzle opening 2a (a direction perpendicular to the plane of FIG. 1). On the other side, a main discharge path 15 is formed.

The main supply path 14 and the space 13 are
The nozzle port 2a and the base 2b are communicated with each other by a branch supply path 16 that is bored. The main discharge path 15
The space and the space are communicated with each other by a branch discharge passage 17 formed in the nozzle mouth 2a and the base 2b. Although only one branch supply passage 16 and one branch discharge passage 17 are shown in the drawing, a plurality of branch supply passages 16 and a plurality of branch discharge passages 17 are actually provided at predetermined intervals along the longitudinal direction of the main body 1.

As shown in FIG. 2, the portion of the elastic sheet 4 corresponding to the branch supply path 16 is the branch supply path 1.
6 is formed in a small-diameter hole 18 having a smaller diameter than the inner diameter. Therefore, when the cleaning liquid supplied to the main supply path 14 branches into the branch supply path 16 and flows to the space 13, the pressure of the cleaning liquid flowing through the small-diameter hole 18 causes the elastic sheet 4 to flow.
The portion of the small diameter hole 18 repeats elastic deformation.

As a result, the cleaning liquid flows into the flow path 5 while pulsating, so that the main body 1 vibrates due to the pulsation of the cleaning liquid. At this time, the frequency of vibration of the main body 1 is 1 to
It is a low frequency of several tens of kHz. That is, the elastic sheet 4
The small-diameter hole 18 serves as vibration generating means for vibrating the main body 1.

A vibrator 19 is joined and fixed to the upper surface of the vibrating plate 9. The vibrator 19 includes an ultrasonic oscillator 21
Supplies a drive signal of a predetermined frequency. Thus, the vibrator 19 is ultrasonically vibrated at about 1 to 3 MHz.

The main body 1 vibrates when the frequency of vibration is low, but does not vibrate at high frequencies in the MHz band. Therefore, even if the diaphragm 9 is ultrasonically vibrated by the vibrator 19, the vibration does not cause the main body 1 to vibrate.

When the object to be cleaned is cleaned by the ultrasonic cleaning apparatus having the above-described structure, the cleaning liquid is supplied to the main supply path 14, and the vibrator 19 is driven by the ultrasonic oscillator 21. The plate 9 is ultrasonically vibrated.

The cleaning liquid supplied to the main supply path 14 flows into the space 13 through the branch supply path 16, contacts the vibration plate 9 and is subjected to ultrasonic vibration, and then flows to the flow path 5. It is ejected from the nozzle port 6 at the tip of the road 5. The cleaning liquid overflowed from the flow path 5 is discharged from the branch discharge path 17 through the main discharge path 15.

Therefore, if the object to be cleaned is disposed at a position facing the nozzle port 6, the object to be cleaned can be cleaned with a cleaning liquid to which ultrasonic vibration has been applied. If the cleaning liquid supplied to the main supply path 14 contains bubbles,
The bubbles adhere to the inner surface of the channel 5 and grow gradually. If the bubbles increase in size and the buoyancy is greater than the flow rate of the cleaning liquid flowing through the flow path 5, the bubbles may float against the flow rate of the cleaning liquid flowing through the flow path 5 and may adhere to the lower surface of the diaphragm 9.

However, when the cleaning liquid supplied to the main supply path 14 flows through the branch supply path 16, it passes through the narrow hole 8 formed in the elastic sheet 4 and having a smaller diameter than the branch supply path 16. Pulsation occurs in the cleaning liquid, and the pulsation causes
Vibrates.

For this reason, bubbles contained in the cleaning liquid are removed from the flow path 5.
Even if it adheres to the inner surface of the
It is separated from the inner surface of the flow path 5 by the vibration of the main body 1 and flows out of the nozzle port 6 together with the cleaning liquid.

Therefore, the operation in a so-called idle cooking state, in which bubbles contained in the cleaning liquid adhere to the diaphragm 9 and the diaphragm 9 vibrates ultrasonically in that state, is prevented.
The vibration plate 9 is prevented from being locally heated and damaged, and the heat prevents the vibrator 19 attached to the vibration plate 9 from being heated and damaged.

In the first embodiment, the elastic sheet 4
Although the small-diameter hole 18 is formed only in the portion corresponding to the branch supply passage 16, the small-diameter hole 1 is also formed in the portion corresponding to the branch discharge passage 17.
8 may be formed.

FIG. 3 shows a second embodiment of the present invention. The same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. In this embodiment, electric vibrators 31 are attached to both sides of the nozzle port 6 on the lower surface of the nozzle port body 2a as vibration generating means. The vibrator 31 is supplied with power via an operation unit 32.

The driving of the vibrator 31 is performed by the operation unit 32.
It can be set by. For example, the vibrator 31 is continuously driven at a predetermined strength,
The driving pattern can be arbitrarily set, such as intermittent driving.

Since the vibrator 31 is provided on the outer surface of the main body 1 to vibrate the main body 1, maintenance and inspection thereof can be easily performed. In addition, since the vibrator 31 is of an electric type, the vibration mode of the main body 1, for example, the intensity of vibration, can be set so as to reliably remove air bubbles adhering to the inner surface of the flow path 5.

In the second embodiment, the main body 1 has the same configuration as that of the first embodiment. However, the configuration of the main body 1 is not particularly limited. Even if it is not divided into 2a and base 2b,
No problem.

[0038]

According to the first to third aspects of the present invention,
By vibrating the main body in which the flow path of the cleaning liquid is formed by the vibration generating means, it is possible to prevent bubbles contained in the cleaning liquid from adhering and remaining on the inner surface of the flow path.

As a result, even if air bubbles adhere to the flow channel, the air bubbles do not grow until they become buoyant against the flow velocity of the cleaning liquid flowing through the flow channel. The bubbles prevent the ultrasonic vibration in a state where a part of the vibration plate does not contact the cleaning liquid.

According to the second aspect of the present invention, the main body is divided into a nozzle opening and a base, and these are joined in a liquid-tight manner via an elastic sheet. The main body was made to vibrate.

For this reason, when the main body is divided into a nozzle opening and a base in order to facilitate the manufacture of the main body, the main body can be vibrated by using an elastic sheet which is naturally required. Therefore, there is no need to use dedicated parts.

According to the third aspect of the present invention, the main body is vibrated by providing the vibrator in the main body, so that the main body is vibrated in a desired mode to prevent adhesion of bubbles. It becomes possible.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an ultrasonic cleaning device according to a first embodiment of the present invention.

FIG. 2 is an enlarged view of a portion of the branch supply path where an elastic sheet is provided.

FIG. 3 is a cross-sectional view of an ultrasonic cleaning apparatus according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Body 2a ... Nozzle mouth 2b ... Base 4 ... Elastic sheet 5 ... Flow path 9 ... Vibrating plate 16 ... Branch supply path (supply path) 18 ... Small diameter hole 19 ... Vibrator 31 ... Vibrator

Claims (3)

[Claims] 1. An ultrasonic cleaning apparatus for applying ultrasonic vibration to a cleaning liquid for cleaning an object to be cleaned, comprising: a main body having a flow path through which the cleaning liquid is supplied; and a main body facing the flow path. A vibrating plate, a vibrator attached to the vibrating plate for ultrasonically vibrating the vibrating plate, and vibrating the main body to prevent air bubbles contained in the cleaning liquid from adhering and remaining at a portion of the main body contacting the cleaning liquid. An ultrasonic cleaning apparatus comprising: a vibration generating unit. 2. The main body comprises a nozzle opening in which the flow passage is formed, and a base to which the nozzle opening is joined and fixed in a liquid-tight manner via an elastic sheet. A supply path for supplying the cleaning liquid to the flow path is formed across the mouth body, and the vibration generating means has a portion of the elastic sheet corresponding to the supply path formed with a smaller diameter than the supply path. 2. The ultrasonic cleaning apparatus according to claim 1, wherein the ultrasonic cleaning apparatus comprises a small diameter hole. 3. The ultrasonic cleaning apparatus according to claim 1, wherein said vibration generating means comprises a vibrator provided on said main body.