JPH01259536A - Method and device for cleaning both sides of substrate using ultrasonic cleaning spray nozzle - Google Patents

Abstract

PURPOSE:To enable foreign contaminative objects adheres to the surface of a substrate to be cleaned to be removed efficiently by centrally spraying cleaning liquid, where ultrasonic vibration is propagated with a sharp angle to a substrate surface against the direction of revolution, to both sides of the substrate while rotating the substrate to be cleaned. CONSTITUTION:Supporting means for supporting a substrate to be cleaned 1 with at least three fixing tools 3 so that they can rotate, means where at least one ultrasonic cleaning spray nozzle 5 is opposed to both surfaces of the substrate 1 with a sharp slope to the rotary surface of the substrate 1, and means for scanning a ultrasonic cleaning spray nozzle 5 in radius direction of the rotary substrate are provided. Then, the plate-like substrate to be cleaned 1 is rotated and washing liquid is centrally sprayed while rotating it in radius direction of the rotary central axis of the substrate. It allows contaminated foreign objects on both surfaces of the substrate to be cleaned to be eliminated simultaneously in a short time and with improved efficiency.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a cleaning method and cleaning apparatus for a substrate using an ultrasonic cleaning spray nozzle, and particularly to a cleaning method and cleaning apparatus suitable for cleaning both sides of a substrate at the same time. Regarding equipment.

[Conventional technology]

As is well known, conventional ultrasonic cleaning methods mainly involve providing a cleaning liquid and an ultrasonic generation means in a cleaning tank, and cleaning the object by immersing the object in the tank.

However, recently, an ultrasonic cleaner has been proposed that eliminates this cleaning tank and uses a cleaning spray nozzle that can propagate ultrasonic vibrations into the cleaning water itself, spraying this cleaning water onto the object being cleaned. has been done.

Note that related devices of this type include, for example, Japanese Patent Application Laid-Open No. 56-6077.

[Problem to be solved by the invention]

The above conventional technology uses a method in which pure water is supplied to a spray nozzle equipped with an ultrasonic vibrator, and the vibrator is caused to oscillate to irradiate a portion of the object to be cleaned with pure water carrying ultrasonic vibrations. However, no consideration was given to a method and apparatus for cleaning both sides of an object at the same time, and there were many technical issues that needed to be improved in order to improve the ability to remove contaminated foreign matter and shorten the processing time.

An object of the present invention is to solve the above-mentioned technical problems, and the first object is to provide an improved method for cleaning a substrate to be cleaned, which can quickly and efficiently remove contaminated foreign matter adhering to the surface of the substrate to be cleaned. A second purpose is to provide a cleaning device.

[Means to solve the problem]

The first purpose is to rotate a plate-shaped substrate to be cleaned and apply a cleaning liquid to both sides of the substrate, in which ultrasonic vibrations are propagated against the direction of rotation of the substrate and at an acute angle with respect to the substrate surface. This is achieved by a method of cleaning both surfaces of a substrate using an ultrasonic spray nozzle, which is characterized by intensive spraying and spraying while scanning in the radial direction of the central axis of rotation.

The second object is to provide a support means for rotatably supporting a substrate to be cleaned with at least three fixing jigs, and a supporting means that is tilted at an acute angle with respect to the rotational surface of the substrate in a direction opposite to the rotational direction of the substrate. A cleaning device comprising: means for arranging at least one ultrasonic cleaning spray nozzle to face each side of the substrate; and means for scanning the ultrasonic cleaning spray nozzle in a radial direction of the rotating substrate. achieved by the device.

In the cleaning device, preferably the at least three
At least one of the fixing jigs is a rotary drive body, and at least two other fixing jigs support the substrate to be cleaned, and the fixing jig is movable in a direction away from the central axis of the rotating substrate. In this way, it is desirable to have a configuration in which the substrate to be cleaned can be attached and detached by moving the fixing jig.

More preferably, the ultrasonic cleaning spray nozzle scanning means includes ultrasonic cleaning spray nozzle scanning means that allows the ultrasonic cleaning spray nozzles, which are disposed opposite to each other on both surfaces of the substrate to be cleaned, to scan and move in the radial direction of the rotating substrate in synchronization with each other. It is desirable to be present.

When the substrate to be cleaned is, for example, a disk substrate for a recording medium such as a magnetic disk or an optical disk, it is possible to realize a disk substrate cleaning apparatus having an excellent cleaning effect.

Note that the above-mentioned ultrasonic cleaning spray nozzle may be a well-known nozzle having a function of jetting out a cleaning liquid and transmitting ultrasonic waves to the cleaning liquid.

In addition, the cleaning liquid is ejected at an acute angle with respect to the surface of the cleaning substrate, and this angle of inclination is important in relation to cleaning power, and an angle of about 30" is the best, and this is the best in the world. A range of ±15” is practical.

Furthermore, the scanning movement direction of the ultrasonic cleaning spray nozzle can be reciprocated from the outer circumference toward the center or further from the center toward the outer circumference, but preferably,
It is preferable to move unilaterally from the center toward the outer circumference.

It is desirable to set the distance from the nozzle tip to the substrate surface to an optimal value depending on the frequency of the ultrasonic wave.
It is within mm, more preferably within 10 mm.

Further, the inclination angle θ of the ultrasonic cleaning spray nozzle with respect to the rotating substrate is desirably an acute angle as described above, and in practical terms, a range of 30 ± 158 is more preferable, and particularly preferably about 30 nozzles.

The ultrasonic cleaning spray nozzles arranged on both sides of the substrate to be cleaned scan and move in synchronization with each other as described above.
This is preferably done by moving the nozzles from one side to the other side by means of known scanning means, such as a link mechanism.

[Effect]

By means of supporting a cleaning substrate fixing jig having a rotation mechanism,
The substrate to be cleaned is rotated in a fixed direction.

In addition, the ultrasonic cleaning spray nozzle installed at an angle on the surface of the substrate to be cleaned is fixed at a distance from the surface of the substrate to be cleaned at a distance that provides the best propagation efficiency of ultrasonic vibration, and the inclination angle of the nozzle is It scans and moves from the center of the substrate to be cleaned toward the outer periphery, or vice versa, while keeping the distance constant. As a result, both sides of the substrate to be cleaned are simultaneously cleaned in a single process, making it possible to efficiently remove contaminants in a short period of time.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

First, to explain the outline of each figure, FIG. 1 is a schematic front view illustrating the configuration of a double-sided substrate cleaning apparatus according to the present invention. 2 is a side view, FIG. 3(a) is an explanatory diagram showing the rotation direction (arrow 17) of the substrate 1 to be cleaned and the scanning movement direction 18 of the spray nozzle 5, and FIG. 3(b) is an illustration of the spray nozzle 5. FIG. 2 is a diagram for explaining the inclination angle θ with respect to the substrate surface 1 and the distance d from the nozzle tip to the substrate surface. Figure 4 shows a characteristic curve diagram of the results of examining the contaminant removal rate and irradiation distance to determine the distance @d between the spray nozzle and the cleaning substrate 1, and Figure 5 shows the characteristic curve when the inclination angle θ is used as a parameter. FIG. 3 is a characteristic curve diagram showing the relationship between foreign matter removal rate and cleaning time.

To explain each figure in more detail below, the substrate to be cleaned 1 shown in FIGS. It will be installed. The mounted cleaning substrate 1 is connected to a substrate fixing jig 2 having a rotation mechanism by a drive motor 8 via a drive transmission section 12.
Rotates in a fixed direction by rotating. Ultrasonic vibrations are applied to the rotating cleaning substrate 1 from ultrasonic spray nozzles 5 provided on both sides of the cleaning substrate, and pure water is supplied from the water tank 9 through the water supply pipe 11 and through a conduit (not shown). and irradiated. This ultrasonic spray nozzle 5
is moved by a drive device 8 along a guide 7 provided to maintain a constant distance and angle from the cleaning substrate 1 . Note that power is transmitted to the nozzle 5 from a drive device 8 via a support rod 4 and a support stand 6. Further, the pure water irradiated from the ultrasonic spray nozzle 5 (originally it should be expressed as injection, but since ultrasonic waves are also added, it is referred to as irradiation here) is passed from the pure water supply tank 9 through the water supply pipe 11. supplied,
The drained liquid after cleaning is returned to the drained liquid tank 10 through a communication passage 16 provided in the bottom partition plate 14 of the cleaning chamber 15. Further, the apparatus is covered with a scattering prevention cover 13 to prevent the purified water irradiated from the ultrasonic spray nozzle 5 and the removed contaminated foreign matter from scattering elsewhere and to prevent contamination of the cleaning substrate 1.

As described above, the distance d between the ultrasonic spray nozzle 5 and the cleaning substrate 1 in the substrate double-sided cleaning apparatus explained in FIGS. 1 and 2.
, the scanning movement direction 18 of the nozzle, the inclination angle θ, and the rotation direction 17 of the substrate 1 are detailed in FIGS. 3(a) and 3(b). The distance over which ultrasonic vibrations are efficiently applied to the pure water 19 irradiated from the ultrasonic spray nozzle 5 and contaminant foreign matter is removed is limited.

This distance d is determined by the contaminant removal rate and distance d shown in Figure 4.
From the relationship, the removal rate is close to 100% at about 10 mm, which is practically within 20 mm, preferably within 10 inches.

In FIG. 5, the distance d between the substrate 1 to be cleaned and the nozzle 5 is 10+
It is a characteristic curve diagram of the result of measuring how the inclination angle θ affects the cleaning effect when ++m. In other words, from this figure, when θ=308, the cleaning time is 30 seconds.
It can be seen that the removal rate reached 100% at ec, and 308 was the optimum tilt angle. Practically, the range is 30''±158.

For reference, the rotation direction 17 of the substrate 1 is shown in the above figure 3 (
When the direction was reversed to a), the foreign matter removal rate was markedly degraded and was not practical.

Further, in the above embodiment, a metal disc for a magnetic disk was used as the substrate 1 to be cleaned, but it goes without saying that it is applicable not only to metal but also to glass plates and any other substrates that require cleaning. do not have.

Furthermore, the cleaning liquid is not limited to water, and any commonly used organic or inorganic cleaning agent can be used.

〔Effect of the invention〕

According to the present invention, both sides of a substrate to be cleaned can be cleaned simultaneously in a short time.
In addition, since it is possible to remove contaminated foreign matter with high efficiency, it is effective in high cleaning and short processing time in substrate cleaning, and it has been able to sufficiently solve the conventional technical problems.

[Brief explanation of the drawing]

FIG. 1 is a schematic front view of a double-sided substrate cleaning apparatus according to an embodiment of the present invention, FIG. 2 is a side view thereof, and FIG. FIG. 3(b) is a front view of the main parts to explain the angle of inclination θ of the ultrasonic spray nozzle with respect to the substrate, and FIG. 4 shows the relationship between the distance between the ultrasonic spray nozzle and the cleaning substrate and the foreign matter removal rate. The remaining characteristic curve diagram, FIG. 5, is a characteristic curve diagram showing the relationship between the cleaning time and the foreign matter removal rate when the nozzle inclination angle θ is taken as a parameter. In fig. 1... Substrate to be cleaned 2... Fixing jig with rotating mechanism 3... Fixing jig 4... Support rod 5... Ultrasonic spray nozzle 6... Support stand 7... Guide 8 ... Drive device 9 ... Pure water tank 10 ... Drainage tank 11 ... Water supply piping 12 ... Drive transmission part 13 ... Scattering prevention cover 14 ... Threshold plate] 5 ... Washing Room Representative Patent Attorney Nakamura
Junnosuke (a) Figure 3 Figure 4

Claims (1)

[Claims] 1. While rotating a plate-shaped substrate to be cleaned, a cleaning liquid in which ultrasonic vibrations are propagated to both sides of the substrate in a direction opposite to the direction of rotation of the substrate and at an acute angle with respect to the substrate surface is applied to the substrate. Concentrated injection while scanning in the radial direction of the central axis of rotation.
A method for cleaning both sides of a substrate using an ultrasonic spray nozzle characterized by spraying water onto the substrate. 2. Supporting means for rotatably supporting the substrate to be cleaned with at least three fixing jigs, and supporting means for rotatably supporting the substrate to be cleaned with at least three fixing jigs; 1. A cleaning device comprising: means for opposing at least one ultrasonic cleaning spray nozzle; and means for scanning the ultrasonic cleaning spray nozzle in a radial direction of a rotating substrate. 3. At least one of the at least three fixing jigs is a rotational drive body, and at least two other fixing jigs support the substrate to be cleaned, and the fixing jig is moved in a direction away from the central axis of the rotating substrate. 3. The cleaning apparatus according to claim 2, wherein the cleaning apparatus is configured to be movable so that the substrate to be cleaned can be attached or detached by moving the fixing jig. 4. The ultrasonic cleaning spray nozzle scanning means is configured to allow the ultrasonic cleaning spray nozzles disposed facing each other on both surfaces of the substrate to be cleaned to scan and move in the radial direction of the rotating substrate in synchronization with each other. The cleaning device according to claim 2, characterized in that: 5. The disk substrate cleaning apparatus according to claim 2, 3 or 4, wherein the substrate to be cleaned is a disk substrate for a recording medium.