JPH1064868A - Device and method for cleaning substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent particles from being adhered again and remove the particles regardless of their size. SOLUTION: A nozzle part 15 is provided with a discharge port in which a cleaning liquid can be discharged at such a flow rate enough to propagate low-frequency ultrasonic vibration with a range of 20 to 700kHz, and the low-frequency ultrasonic vibration and high-frequency ultrasonic vibration with a range of 800 to 3000kHz where the ultrasonic vibration is easy to be propagated comparatively are combined together and they can be given to the cleaning liquid. Therefore, small particles with a diameter of at most around 3μm can be removed by high-frequency ultrasonic vibration, and comparatively large particles with a diameter of at most around 10μm can be use also removed by low-frequency ultrasonic vibration. In the water-flowing type ultrasonic cleaning, the particles separated from a substrate 2 are quickly discharged together with the flow of water in comparison with the water-pooling type ultrasonic cleaning, so that the substrate 2 is hardly contaminated again.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used in, for example, a semiconductor manufacturing apparatus and a liquid crystal display substrate manufacturing apparatus. The present invention relates to a square glass substrate for a liquid crystal display, a glass substrate for a color filter, a substrate for a photomask, a ceramic substrate for a thermal head, The present invention relates to a substrate cleaning apparatus and a substrate cleaning method for cleaning a substrate surface such as a printed circuit board and a semiconductor wafer.

[0002]

2. Description of the Related Art Conventionally, a substrate cleaning apparatus is provided at an appropriate position in a substrate processing apparatus having a developing device, an etching device, and the like, and is used between a pre-process and a post-process of a substrate process, a final finishing process of the substrate process, and the like. The cleaning liquid is used to prevent the processing liquid used in the previous processing from remaining on the substrate surface and to clean the substrate surface.

As such a substrate cleaning apparatus, as shown in FIG. 6, an ultrasonic generator 32 is provided at the bottom of a cleaning tank 31, and the ultrasonic generator 32 allows pure water in the cleaning tank 31 to be removed. Ultrasonic vibration of a relatively low frequency of 20 KHz to 700 KHz is applied to the cleaning liquid to remove particles adhering to the substrate 33 immersed in the cleaning liquid to clean the substrate 33.

As another substrate cleaning apparatus, as shown in FIG. 7, a plurality of transport rollers 41 horizontally transport a substrate 42 while transporting the substrate 42 from a slit-like discharge port of an ultrasonic cleaning member 43 to a megahertz. Level (800 KHz to 2
The cleaning liquid to which ultrasonic vibration of a relatively high frequency of 000 KHz is applied is supplied in a curtain shape in the width direction of the substrate 42 to remove particles adhering to the substrate 42 and clean the substrate 42.

Further, as another substrate cleaning apparatus, as shown in FIG. 8, the substrate 51 is placed and supported on the upper surface in a state where the four corners of the substrate 51 are positioned by the positioning pins 52, and the central shaft is also supported. A circular substrate support member 53 rotatable about P1 is provided. The drive arm 54
At the megahertz level (800 kHz to 200 kHz)
Nozzle portion 5 which discharges a cleaning liquid to which ultrasonic vibration of a relatively high frequency (0 KHz) is applied from a slit-shaped discharge port.
The ultrasonic cleaning means 56 having the number 5 is provided. The drive arm 54 is connected to the substrate 51 by a drive mechanism (not shown).
With the upper surface of the substrate and the nozzle portion 55 separated from each other by a predetermined distance, the nozzle portion passes through the center portion of the substrate 51 around the central axis P2 near the substrate support member 53 as the center of rotation. 55 is configured to swing. In this manner, the substrate 51 is placed horizontally on the rotatable substrate support means 53, and the nozzle part 55 is swung on the substrate 51 while rotating the substrate 51 together with the substrate support means 53, thereby causing the nozzle part 5 to rotate.
The cleaning liquid to which ultrasonic vibration has been applied from 5 is supplied to the substrate 51, and particles adhered to the substrate 51 are removed to clean the substrate 51.

[0006]

700 kHz capable of removing relatively large particles of 3 μm or more
The following relatively low frequency ultrasonic vibration cannot be satisfactorily applied to the cleaning liquid by the conventional flowing water type supply device. For example, in the ultrasonic cleaning unit 43 of FIG. 7 and the ultrasonic cleaning unit 56 of FIG. Has used a cleaning liquid to which ultrasonic vibration of a relatively high frequency of a megahertz level (for example, 800 KHz to 2000 KHz) is applied in a flowing water type nozzle portion, but the particle size range of particles that can be effectively cleaned is 1 μm. There is a problem that particles are limited to particles as small as about 3 μm and particles larger than 3 μm or more cannot be effectively removed.

Further, for example, in the configuration of the reservoir type of the cleaning tank 31, even if ultrasonic vibration of a relatively low frequency of 20 kHz to 700 kHz is applied to the cleaning liquid, the vibration can be satisfactorily applied to the cleaning liquid. From 3 μm or more can be removed. However, there is a problem that the particles detached from the substrate 33 diffuse into the cleaning liquid in the cleaning tank 31 and contaminate the substrate 33 and the cleaning tank 31. In particular, when the substrate 33 was taken out of the cleaning tank 31 after the substrate was cleaned, particles floating in the cleaning liquid were re-adhered to the substrate 33. In order to suppress the contamination of the cleaning liquid in the cleaning tank 31, circulation filtration was performed by overflow or the like, but completely floating particles could not be removed from the cleaning liquid.
There is a possibility that the floating particles may adhere to the substrate 33 again.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems. In addition to preventing the particles from re-adhering, the present invention also removes large-sized particles which could not be removed by conventional flowing water type ultrasonic cleaning. It is an object of the present invention to provide a substrate cleaning apparatus and a substrate cleaning method that can perform the method.

[0009]

SUMMARY OF THE INVENTION A substrate cleaning apparatus according to the present invention is a substrate cleaning apparatus for cleaning a substrate by supplying a cleaning liquid provided with ultrasonic vibrations to the substrate. Having an ultrasonic generator for applying low-frequency ultrasonic vibration to the cleaning liquid, and at a flow rate sufficient for the low-frequency ultrasonic vibration to propagate through the cleaning liquid, the cleaning liquid toward the substrate supported by the support means. It has a nozzle portion for discharging. Preferably, the low frequency is 20 kHz to 700 kHz.
z. At this time, it is preferable to clean the substrate by relatively moving the substrate to be cleaned and the nozzle unit for supplying the cleaning liquid to which the ultrasonic vibration is applied to the substrate in a direction along the main surface of the substrate. .

With this configuration, the nozzle portion is ejected at a flow rate sufficient to transmit low-frequency ultrasonic vibration for removing large-sized particles, so that high-frequency ultrasonic vibration as in the prior art is applied. Large particles that could not be removed by the cleaning liquid can be removed from the substrate surface by the cleaning liquid to which low-frequency ultrasonic vibration has been applied. At this time, the particles detached from the substrate are quickly discharged at a sufficient flow rate of the cleaning liquid, so that reattachment to the substrate is suppressed.

Further, the substrate cleaning apparatus of the present invention is a substrate cleaning apparatus for cleaning a substrate by supplying a cleaning liquid to which ultrasonic vibration is applied to the substrate, wherein the substrate is supported by the substrate and the substrate is supported by the support means. A first nozzle that ejects a cleaning liquid to which a relatively low frequency ultrasonic vibration is applied toward the substrate, and a relatively high frequency ultrasonic vibration is applied to the substrate supported by the support means. And a second nozzle for discharging the cleaning liquid. At this time, it is preferable to clean the substrate by relatively moving the substrate to be cleaned and the first nozzle and the second nozzle in a direction along the main surface of the substrate.

With this configuration, the cleaning liquid to which the ultrasonic vibration of a relatively low frequency is applied is discharged from the first nozzle,
Since the cleaning liquid to which the ultrasonic vibration of a relatively high frequency is applied is discharged from the second nozzle, the ultrasonic vibration of a low frequency and the ultrasonic wave of a high frequency including the large particles which could not be removed conventionally. The substrate can be removed from the substrate surface with the cleaning liquid to which the sonic vibration has been applied.
At this time, the particles detached from the substrate are quickly discharged at a sufficient flow rate of the cleaning liquid, so that reattachment to the substrate is suppressed.

[0013] Further, the substrate cleaning apparatus of the present invention is a substrate cleaning apparatus for cleaning a substrate by supplying a cleaning liquid to which ultrasonic vibration is applied to the substrate.
A nozzle for ejecting the cleaning liquid to which the ultrasonic vibration is applied toward the substrate supported by the supporting means, and switching the frequency of the ultrasonic vibration to be applied to the cleaning liquid to one of a relatively low frequency and a relatively high frequency Frequency switching means. At this time, it is preferable to clean the substrate by relatively moving a substrate to be cleaned and a nozzle for supplying a cleaning liquid to which ultrasonic vibrations have been applied to the substrate in a direction along the main surface of the substrate.

According to this configuration, if the relatively low frequency ultrasonic vibration and the relatively high frequency ultrasonic vibration are switched in time series by the frequency switching means, only one ultrasonic generator is required. If two ultrasonic generators that output the same ultrasonic vibration switch to another ultrasonic vibration in a time series, the driving time becomes longer, but different ultrasonic waves are generated by the two ultrasonic generators. The ultrasonic output is doubled as compared with the case where vibration is output.

Further, preferably, the low frequency in the substrate cleaning apparatus of the present invention is in a range of 20 kHz to 700 kHz, and the high frequency is in a range of 800 kHz to 300 kHz.
It is in the range of 0 KHz.

According to this configuration, as the ultrasonic frequency becomes lower, particles having a larger size can be removed.
By applying an ultrasonic frequency in the range of Hz to 700 KHz to the cleaning liquid, particles having a size of 10 μm or less can be removed, and 800 KHz to 3000 KH.
If an ultrasonic frequency in the range of z is applied to the cleaning liquid, it is possible to remove even smaller particles of about 3 μm or less.

Further, in the substrate cleaning apparatus of the present invention,
Preferably, a high-pressure nozzle for discharging the cleaning liquid at a high pressure toward the substrate supported by the support means is provided. Preferably, the cleaning device further includes a cleaning brush that abuts on a main surface of the substrate supported by the support unit and brush-cleans the substrate.

According to this configuration, the low frequency ultrasonic wave,
10μ for ultrasonic cleaning with high frequency ultrasonic
m can be removed, and in addition to this, 10
Particles as large as μm or more can be washed, and a high-pressure nozzle can remove non-contact, scratch-free and persistent dirt. Thus, the synergistic effect of cleaning is obtained by utilizing the characteristics of each cleaning member.

Further, in the substrate cleaning apparatus according to the present invention, the means for relatively moving the substrate and the nozzle includes a substrate holding member for holding and rotating the substrate, and a substrate on the rotating substrate held by the substrate holding member. May be provided with a nozzle moving member that moves the nozzle in an arc shape around a position near the substrate holding member as a rotation center.

With this configuration, the ultrasonic cleaning for preventing the particles from re-adhering and removing the particles regardless of the particle size can be easily applied to the rotary type substrate cleaning apparatus. In this case, since the nozzle moves on the rotating substrate in the radial direction of rotation, the nozzle has a minimum discharge area, it is possible to minimize the flow rate of the cleaning liquid, and the centrifugal force is added to the flowing water type. Thus, the particles are scattered together with the cleaning liquid, so that the reattachment of the particles to the substrate is further suppressed.

Next, in the substrate cleaning method of the present invention, in a substrate cleaning method of cleaning a substrate by supplying a cleaning liquid to which ultrasonic vibration is applied to the substrate, ultrasonic vibration of a relatively low frequency is applied to the cleaning liquid. And a step of discharging the cleaning liquid toward the substrate at a flow rate sufficient to transmit low-frequency ultrasonic vibrations into the cleaning liquid.

With this configuration, in the conventional non-contact ultrasonic cleaning, which is of a flowing water type and capable of preventing particles from re-adhering, only a relatively high frequency ultrasonic cleaning can be performed, and a size of about 3 μm or less can be achieved. Although only small particles could be removed, the cleaning liquid was discharged at a flow rate sufficient to transmit ultrasonic vibration of a relatively low frequency to clean the substrate, so removing large particles of 3 μm or more in size was necessary. Becomes possible. Further, if ultrasonic cleaning of a relatively high frequency is performed in addition to the ultrasonic cleaning of a relatively low frequency, particles such as large particles having a size of 3 μm or more and small particles having a size of about 3 μm or less can be obtained regardless of the particle size. Can be removed. In this case, the low ultrasonic vibration and the high ultrasonic vibration are simultaneously or separately applied to the cleaning liquid by a nozzle having a flow rate sufficient to transmit the low ultrasonic vibration.

Further, the substrate cleaning method of the present invention is a substrate cleaning method for cleaning a substrate by supplying a cleaning liquid to which ultrasonic vibration is applied to the substrate, wherein a relatively low frequency ultrasonic vibration is applied to the substrate. And discharging a cleaning liquid to which a relatively high frequency ultrasonic vibration is applied toward the substrate.

With this configuration, if the step of discharging the cleaning liquid to which the relatively high ultrasonic vibration is applied and the step of discharging the cleaning liquid to which the relatively low ultrasonic vibration is applied are separately configured, the cost is high. The step of discharging the cleaning liquid in which the ultrasonic vibration is applied to the cleaning liquid does not require a sufficient flow rate for transmitting the low ultrasonic vibration, and the supply amount of the cleaning liquid can be reduced.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a substrate cleaning apparatus according to the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing the structure of a substrate cleaning apparatus according to one embodiment of the present invention.

In FIG. 1, a substrate cleaning apparatus 1 includes a circular substrate holding member 3 serving as a rotatable supporting means for mounting and supporting a substrate 2 on an upper surface and a vertical rotating shaft 4 for rotating the substrate holding member 3. A drive motor 5 serving as a rotary drive unit for rotating and driving through the interface, a liquid collecting discharge means 6 surrounding the substrate holding member 3 and collecting the cleaning liquid scattered at the time of cleaning, and a position near the liquid collecting discharge means 6 The cleaning liquid is discharged toward the upper surface of the substrate 2 by applying a cleaning liquid provided with a low-frequency ultrasonic vibration (in this embodiment, a frequency of 20 kHz to 700 kHz) for removing large-sized particles. Cleaning means 7 and ultrasonic cleaning means 7
Control means 8 for controlling the driving and ultrasonic driving
And

As a substrate holding mechanism for the substrate holding member 3, a vacuum chuck (not shown) is provided.
It is provided at the center part concentrically with the rotation center axis, and is configured to adsorb and hold the placed substrate 2.
In the present embodiment, the vacuum chuck is used. Alternatively, a configuration may be employed in which the four corners of the substrate 2 are positioned by the same two positioning pins 52 as shown in FIG. The driving motor 5 is configured to transmit a rotational driving force to the vertical rotating shaft 4 connected to the center of the substrate holding member 3 via a driving force transmitting unit or the like.

The liquid collecting and discharging means 6 has an annular liquid collecting hood 10 erected so as to surround the substrate holding member 3 from the peripheral edge of the circular bottom, and an upper end at the bottom of the liquid collecting hood 10. Are provided, and an annular liquid collection duct 12 to which the lower end of each of the communication tubes 11 is connected, and is spun outward by centrifugal force due to rotation of the substrate 2 during cleaning. The washing liquid is captured by the annular wall and the bottom of the collecting hood 10 and is connected to the connecting pipe 11 with the sucked airflow.
Further, the gas passes through the liquid collecting duct 12, and thereafter, is subjected to a gas-liquid separation process, and is discharged out of the system.

Further, the ultrasonic cleaning means 7 includes a vertical rod 13 erected at a position near the other end of the liquid collecting and discharging means 6,
A drive arm 14 extending horizontally at the upper end of the vertical rod 13 and a nozzle 15 provided at the tip of the drive arm 14 for discharging a cleaning liquid to which low-frequency ultrasonic vibrations are applied. And The drive arm 14 moves the center axis 13a of the vertical rod 13 in a state where the upper surface of the substrate 2 and the nozzle portion 15 are separated by a predetermined distance.
Between the rotating ends of the rotating substrate 2 passing through the center of rotation of the rotating substrate 2.
5 has a nozzle moving member (not shown) for swinging and moving it in an arc shape. As described above, the nozzle moving member (not shown) for swinging the nozzle portion 15 at the tip of the drive arm 14 in an arc shape on the substrate 2 is constituted by a drive motor or the like, and the drive control is performed by a control signal from the control means 8. Is made.

The nozzle portion 15 has a width of 1 as in the prior art.
Rather than discharging the cleaning liquid in a curtain shape from a slit-shaped discharge port having a length dimension of the substrate width of about 2 mm to 2 mm, the cleaning liquid is straightly supplied to the substrate 2 from a circular discharge port having a diameter of 1 cm or more. It discharges at a predetermined flow rate.

That is, conventionally, in the case of such a flowing water type ultrasonic cleaning, the frequency is 800 KHz to 3000 KH.
Ultrasonic vibration having a relatively high frequency of z has a slit width of 1
When the cleaning liquid is applied to the cleaning liquid, the cleaning liquid can be satisfactorily applied to the entire surface of the substrate while the cleaning liquid is supplied only to a portion where the cleaning liquid is applied to the substrate 2. In order to apply the cleaning liquid to the substrate 2, the cleaning liquid is supplied in a curtain shape in the width direction of the substrate 2 conveyed in a predetermined direction. Thus, the slit width is 1mm ~
In the case of about 2 mm, the frequency is 20 KHz to 700 K
The ultrasonic vibration having a relatively low frequency of Hz is not satisfactorily applied to the cleaning liquid supplied straight from the discharge port, and conventionally, the frequency is 800 KHz to 3000 KH due to the problem of the flow rate.
Ultrasonic cleaning was realized only by ultrasonic vibration having a relatively high frequency of z. Here, the width of the discharge port of the nozzle portion 15 is 1
When the flow rate is 0 mm or more and the flow rate is 7 liters / minute or more, even a relatively low frequency ultrasonic vibration having a frequency of 20 kHz to 700 kHz can be favorably applied to the cleaning liquid supplied from the discharge port. Further, as described above, since the discharge port is moved with respect to the rotated substrate 2,
Even if the shape of the discharge port is a circular shape with the smallest flow rate of the cleaning liquid, the cleaning liquid can be applied evenly to the entire surface of the substrate 2, and cleaning by high frequency ultrasonic vibration and low frequency ultrasonic vibration is effective. It has been found that the effective cleaning diameter due to the relatively low frequency ultrasonic vibration having a frequency of 20 kHz to 700 kHz is larger than the effective cleaning diameter due to the high frequency ultrasonic vibration.

FIG. 2 is a cross-sectional view schematically showing one example of the nozzle portion 15 at the tip of the arm of the ultrasonic cleaning means 7 in FIG.

In FIG. 2, a vibration plate 16 is provided in the nozzle body of the nozzle portion 15 in the ultrasonic cleaning means 7, and the inside of the nozzle body is partitioned into two spaces 17 and 18 by the vibration plate 16. Vibrators 19 and 20 as ultrasonic generators are attached to the diaphragm 16 in the space 17. These vibrators 19 and 20 are connected to the control means 8
Is driven and controlled by a frequency of 20 KHz to 700 K.
Ultrasonic vibration of a low frequency of Hz is oscillated. As described above, by vibrating the vibration plate 16 by the vibrators 19 and 20, low-frequency ultrasonic vibration is applied to the cleaning liquid supplied to the space 18. The cleaning liquid to which the low-frequency ultrasonic vibration is applied is supplied to the circular discharge port 2.
The ultrasonic cleaning is performed by discharging from 1 to the upper surface of the substrate 2.

In this embodiment, these vibrators 1
Drives 9 and 20 are controlled by the control means 8 so as to oscillate ultrasonic vibrations having a low frequency of 20 KHz to 700 KHz.
0 is driven and controlled by the control means 8 so that different ultrasonic vibrations (frequency 20 kHz to 700 kHz and frequency 800
KHz to 3000 KHz) may be simultaneously oscillated, or the vibrators 19 and 20 may have the same ultrasonic vibration (frequency 20
KHz-700KHz or frequency 800KHz-30
(00 KHz).
In this case, a relatively low frequency ultrasonic vibration for removing large particles (frequency 20 kHz to 70 kHz) is used.
0 KHz) and relatively high frequency ultrasonic vibration for removing small particles (800 KHz to 3 KHz).
A frequency switching means for switching the vibration frequency of 000 KHz) is required in the control means 8. As described above, by vibrating the vibration plate 16 by the vibrators 19 and 20, different ultrasonic vibrations are given to the cleaning liquid supplied to the space 18. The cleaning liquid to which these different ultrasonic vibrations have been applied may be discharged from the circular discharge port 21 toward the upper surface of the substrate 2 to perform ultrasonic cleaning.

The operation of the above configuration will be described below. First, the substrate 2 is placed and fixed at a predetermined position on the substrate holding member 3, and the substrate 2 is driven to rotate together with the substrate holding member 3. Thereafter, the vertical rod 13 of the ultrasonic cleaning means 7 is used.
With the nozzle 15 at the tip of the drive arm 14 being separated by a predetermined distance above the edge of the substrate 2 around the center of rotation, the vibrators 19 and 20 are driven to drive the The cleaning liquid to which each of the sonic vibrations is applied is discharged from the discharge port 21 of the nozzle portion 15 toward the upper surface of the substrate 2, and the nozzle portion 15 is rotated together with the drive arm 14 around the vertical rod 13 as a rotation center. Nozzle part 1
5 is reciprocated in an arc shape from the edge position of the substrate 2 through the center position to the direction of the opposite edge position to perform ultrasonic cleaning of the entire upper surface of the substrate 2.

As described above, the frequency ranges from 20 KHz to 700 KHz.
A cleaning liquid to which ultrasonic vibration having a relatively low frequency in the range of KHz is applied from a nozzle portion to perform ultrasonic cleaning, and a cleaning liquid sufficient for transmitting low-frequency ultrasonic vibration for removing large-sized particles. With such a flow rate, large-sized particles that cannot be removed by the cleaning liquid to which the conventional high-frequency ultrasonic vibration is applied can be removed from the substrate surface.

The frequency is 20 KHz to 700 KHz.
A relatively low frequency ultrasonic vibration in the range of
By applying the cleaning liquid in combination with a relatively high frequency ultrasonic vibration in the range of 00 KHz to 3000 KHz, small particles of about 3 μm or less are removed by the high frequency ultrasonic vibration, and one particle is removed by the low frequency ultrasonic vibration.
By removing relatively large particles of about 0 μm or less, it is possible to effectively perform ultrasonic cleaning over particles of all sizes from small particles to large particles.

At this time, in the flowing water type ultrasonic cleaning, the particles separated from the substrate 2 are quickly discharged together with the flowing water as compared with the stored water type ultrasonic cleaning. As described above, the particles do not re-attach and re-contaminate the cleaned substrate 2. Also,
At this time, the substrate 2 is rotating, and the centrifugal force causes the particles to fly outward together with the cleaning liquid, thereby preventing the substrate 2 from being re-contaminated. Furthermore, in such a conventional stored-water type ultrasonic cleaning, a member for holding the substrate in the stored water, for example, a cassette or a transport roller is required. Since ultrasonic vibration is also applied to such a holding member, if the ultrasonic cleaning process is performed for a long time, an erosion phenomenon occurs, which is damaged, and this causes the generation of particles, and the substrate 2 and the cleaning member are cleaned. Although the tank is further contaminated, there is no such a possibility in the flowing water ultrasonic cleaning of the present invention.

FIG. 3 is a perspective view showing the structure of a substrate cleaning apparatus according to another embodiment of the present invention. Members having the same functions and effects as those of FIG. 1 are denoted by the same reference numerals.

In FIG. 3, an ultrasonic cleaning means for ultrasonic cleaning by discharging a cleaning liquid to which an ultrasonic vibration of a low frequency of 20 KHz to 700 KHz having a large particle removing frequency is applied toward the upper surface of the substrate 2. 7, the frequency for removing small particles is 800 KH
This is a combination of an ultrasonic cleaning unit 31 that discharges a cleaning liquid to which ultrasonic vibration of a high frequency of z to 3000 KHz is applied toward the upper surface of the substrate 2 and performs ultrasonic cleaning. At the end of the drive arm 14 of the ultrasonic cleaning means 7, a nozzle portion 15 as a straight-type first nozzle for discharging a cleaning liquid to which low-frequency ultrasonic vibration is applied is provided. A nozzle portion 32 as a second nozzle of a slit type for discharging a cleaning liquid to which high frequency ultrasonic vibration is applied is disposed at a tip end portion of the drive arm 14 of 31. The nozzle portions 15 and 32 are rotated about the vertical rods 13 and 13 as rotation centers, respectively, and are formed in an arc shape from the edge position of the substrate 2 toward the opposite edge position through the center position. Substrate 2 by alternately reciprocating
Is to perform ultrasonic cleaning of the entire upper surface. At this time,
The supply amount of the cleaning liquid from the nozzle unit 32 in which high ultrasonic vibration is applied to the cleaning liquid does not require a sufficient flow rate for transmitting low-frequency ultrasonic vibration, and the supply amount of the cleaning liquid can be reduced.

Therefore, when the frequency is between 20 kHz and 700 kHz,
A nozzle portion 15 for discharging a cleaning liquid to which ultrasonic vibration having a relatively low frequency in the range of KHz is applied;
By performing ultrasonic cleaning in combination with the nozzle unit 32 that discharges a cleaning liquid to which a relatively high frequency ultrasonic vibration in the range of KHz to 3000 KHz is applied, small particles of about 3 μm or less are generated by the high frequency ultrasonic vibration. By removing the particles and removing relatively large particles of about 10 μm or less by low-frequency ultrasonic vibration, ultrasonic cleaning can be effectively performed over all size particles from small particles to large particles.

In the embodiment shown in FIG. 1, a low frequency ultrasonic cleaning means 7 is used as the cleaning means. In the embodiment shown in FIG. 3, the low frequency ultrasonic cleaning means 7 and the high frequency ultrasonic cleaning means 31 are used. As shown in FIG. 4, the ultrasonic cleaning means 7 and the brush cleaning member 33 are used.
May be combined. At the tip of the drive arm 14 of the brush cleaning member 33, a cleaning brush 34 for brush cleaning is provided. These nozzles 1
5 and the cleaning brush 34 are respectively rotated to alternately reciprocate in an arc shape from the edge position of the substrate 2 through the center position toward the opposite edge position to clean the entire upper surface of the substrate 2. Is what you do. Similarly, a combination of the ultrasonic cleaning means 7 and a high-pressure jet spray cleaning member as high-pressure jet cleaning means may be used. Also,
A high-pressure jet spray cleaning member as high-pressure jet cleaning means may be provided instead of the ultrasonic cleaning means 7. The configuration of the high-pressure jet cleaning means is, for example, provided with a jet injection nozzle (high-pressure nozzle) in place of the cleaning brush 34 shown in FIG.

As described above, for example, the brush cleaning member 33
In this case, the cleaning brush 34 in which the cleaning brush is rotating is alternately swung similarly to the nozzle portion 15 to remove persistent dirt and the like, but particles having a size of 10 μm or less cannot be cleaned, and the frequency is reduced. 20KHz-700K
With ultrasonic cleaning at a frequency of 10 Hz, particles having a size of 10 μm or less can be removed.
3 μm for ultrasonic cleaning from 0 KHz to 3000 KHz
Smaller particles, such as the following, can be removed. Also, for example, in a high-pressure jet spray cleaning member,
As in the case of the nozzle unit 15 of the ultrasonic cleaning unit 7, the jet injection nozzle unit that injects the cleaning liquid at a high pressure alternately swings so that the upper surface of the substrate 2 can be removed without contact and without damaging the dirt. As described above, the characteristics of the respective cleaning members can be utilized to obtain a synergistic effect of cleaning. Here, in FIG. 4, members having the same functions and effects as those of FIG. 1 are denoted by the same reference numerals, and description thereof is omitted.

In each of the above embodiments, the substrate 2 is held by the substrate holding member 3 and rotated, and the substrate 2 held and rotated by the substrate holding member 3 is rotated to a position near the substrate holding member 3. The nozzle 15 moves in an arc shape passing through the center of rotation of the substrate 2 as the moving center.
May have a nozzle moving member that moves in a straight line passing through the center of rotation of the substrate 2 instead of an arc shape. Also,
The lower surface of the substrate 2 may be transported while being transported by the transport roller, and the cleaning liquid to which at least a relatively low frequency ultrasonic vibration is applied may be supplied to the substrate 2 to be cleaned from the fixed nozzle portion. . A specific example of the substrate linear movement method using the transport rollers will be described later. In short,
A nozzle unit for supplying at least a cleaning liquid to which ultrasonic vibration having a relatively low frequency is applied to the substrate 2 and the substrate 2
The substrate 2 may be cleaned by relatively moving in the direction along the upper surface of the substrate 2. Further, even if both the nozzle portion and the substrate 2 are stopped, it is sufficient that at least ultrasonic cleaning can be performed with a cleaning liquid to which ultrasonic vibration having a relatively low frequency is applied. In these cases, in particular, the ultrasonic vibration having a frequency of 800 KHz to 3000 KHz has a cleaning effective range only in a portion where the processing liquid has hit the substrate 2, so the cleaning effective range is narrow, and the processing liquid is applied to the entire surface of the substrate 2. For this purpose, a plurality of discharge ports of the nozzle portion are required.

Further, in the embodiment of FIG.
Nozzle part 32 where high ultrasonic vibration in the range of 3000 KHz is applied to the cleaning liquid, and nozzle part 1 where low ultrasonic vibration in the range of 20 KHz to 700 KHz is applied to the cleaning liquid
5 and 5 are configured separately, but may be configured with the same nozzle unit. In this case, it is possible to reduce the supply amount of the cleaning liquid from the nozzle unit 32 where high ultrasonic vibration is applied to the cleaning liquid.

Further, in the embodiment shown in FIG.
Only low ultrasonic vibration in the range of 700 to 700 KHz is applied to the cleaning liquid.
High ultrasonic vibration in the range of 0 KHz and 20 KHz-70
A low ultrasonic vibration in the range of 0 KHz was applied to the cleaning solution. Thus, the low frequency for removing large particles is in the range of 20 kHz to 700 kHz, and the high frequency for removing small particles is 8 kHz.
Although the frequency range is from 00 KHz to 3000 KHz, the frequency range is not limited to these, and may be divided into three or more frequency ranges.

Further, in the embodiment shown in FIGS. 1 and 3,
The means for relatively moving the substrate 2 and the nozzle portions 15 and 32 includes a substrate holding member 3 for holding and rotating the substrate 2 and a substrate holding member for rotating the substrate 2 held and rotated by the substrate holding member 3. 3 with the position near the center of rotation as the center of rotation.
5, 5 and 32 are moved in an arc shape, but instead of such a substrate rotating type, a substrate linear moving type using a transport roller 35 may be used as shown in FIG. In this case, while the substrate 2 is horizontally supported and transported by the plurality of transport rollers 35, the ultrasonic cleaning member 36 has a wide slit-shaped discharge port (first nozzle) (20K).
A cleaning liquid to which ultrasonic vibration of a relatively low frequency (Hz to 700 kHz) is applied is supplied in a curtain shape in the width direction of the substrate 2, and large-sized particles attached to the substrate 2 are removed to clean the substrate 2. Further, an ultrasonic cleaning member 37 is disposed downstream of the ultrasonic cleaning member 36, and a narrow slit-shaped discharge port of the ultrasonic cleaning member 37 (nozzle port of the second nozzle) (800 KHz or more). 3000KHz)
The cleaning liquid to which the ultrasonic vibration of a relatively high frequency is applied is supplied in a curtain shape in the width direction of the substrate 2 to remove small-sized particles adhering to the substrate 2 to clean the substrate 2. . In this case as well, two nozzles of a relatively low frequency and a relatively high frequency are switched simultaneously or in time series with one nozzle unit, and the cleaning liquid to which the ultrasonic vibration of the low frequency and the high frequency is applied is discharged. It can also be configured as follows. In this case, one or two ultrasonic vibrators are provided in the nozzle portion of the ultrasonic cleaning member 36, and the frequency of an input oscillation signal for one or two ultrasonic vibrators is switched, or two or more ultrasonic vibrators are provided. What is necessary is just to comprise so that a sound wave vibrator may be switched one by one in time series.

[0049]

As described above, according to the present invention, the particles detached from the substrate are quickly discharged with a sufficient flow rate of the cleaning liquid, so that re-adhesion of the particles can be prevented. In addition, since the nozzle portion discharges the cleaning liquid at a flow rate sufficient to transmit low-frequency ultrasonic vibration for removing large-sized particles, a conventional cleaning liquid to which high-frequency ultrasonic vibration is applied is used. Large particles that could not be removed can be easily removed from the substrate surface with a cleaning liquid to which low-frequency ultrasonic vibrations are well applied.

Further, since the nozzle portion discharges at a flow rate sufficient to transmit low-frequency ultrasonic vibration for removing large-sized particles, low-frequency ultrasonic vibration and high-frequency ultrasonic vibration are applied. The cleaning liquid can remove particles regardless of the particle size.
Further, the particles detached from the substrate are quickly discharged at a sufficient flow rate of the cleaning liquid, so that the particles can be prevented from re-adhering.

Further, if low-frequency ultrasonic vibration and high-frequency ultrasonic vibration are switched in a time series by the frequency switching means, necessary different ultrasonic outputs can be obtained with a small number of members.

Further, if the present invention, which can perform ultrasonic cleaning regardless of particle size, by using low-frequency ultrasonic waves and high-frequency ultrasonic waves, if the present invention is adapted to a substrate rotation method,
The flow rate of the cleaning liquid can be minimized, and the particles can be scattered together with the cleaning liquid by the centrifugal force in addition to the flowing water type, so that reattachment of the particles to the substrate can be further suppressed.

Further, if the ultrasonic cleaning is performed in the range of 20 kHz to 700 kHz, particles having a size of 10 μm or less can be removed.
With ultrasonic cleaning in the range of 000 KHz, even smaller particles of about 3 μm or less can be removed.

Further, in addition to the ultrasonic cleaning using low-frequency ultrasonic waves and high-frequency ultrasonic waves, brush cleaning and high-pressure jet cleaning are used to make use of the characteristics of the respective cleaning members, thereby achieving a synergistic effect of cleaning. Can be obtained.

Further, the first nozzle for applying high ultrasonic vibration in the range of 800 KHz to 3000 KHz to the cleaning liquid and the second nozzle for applying low ultrasonic vibration in the range of 20 KHz to 700 KHz to the cleaning liquid are separately provided. The second configuration in which high ultrasonic vibration is applied to the cleaning liquid
The nozzle does not require a sufficient flow rate to transmit low ultrasonic vibration, and the supply amount of the cleaning liquid can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating a configuration of a substrate cleaning apparatus according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view schematically illustrating an example of a nozzle portion at an end of an arm of the ultrasonic cleaning unit in FIG.

FIG. 3 is a perspective view illustrating a configuration of a substrate cleaning apparatus according to another embodiment of the present invention.

FIG. 4 is a perspective view showing a configuration of a substrate cleaning apparatus according to still another embodiment of the present invention.

FIG. 5 is a side view showing a configuration of a substrate transporting type substrate cleaning apparatus according to still another embodiment of the present invention.

FIG. 6 is a cross-sectional view showing a main part configuration of a conventional water reservoir type ultrasonic cleaning apparatus.

FIG. 7 is a side view showing a configuration of a main part of a conventional substrate transfer type ultrasonic cleaning apparatus.

FIG. 8 is a plan view showing a main part configuration of a conventional substrate rotating type ultrasonic cleaning apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate cleaning apparatus 2 Substrate 3 Substrate holding member 5 Drive motor 7, 31 Ultrasonic cleaning means 8 Frequency switching control means 15, 32 Nozzle part 19, 20 Vibrator (ultrasonic generator) 21 Discharge port 33 Brush cleaning member 34 Cleaning Brush 35 Transport rollers 36, 37 Ultrasonic cleaning member

Claims (9)

[Claims] 1. A substrate cleaning apparatus for cleaning a substrate by supplying a cleaning liquid provided with ultrasonic vibrations to the substrate, comprising: a support unit for supporting the substrate; and a supersonic unit for applying ultrasonic vibration of a relatively low frequency to the cleaning liquid. A substrate having a sound wave generator and a nozzle portion for discharging the cleaning liquid toward the substrate supported by the support means at a flow rate sufficient for transmitting the low-frequency ultrasonic vibrations through the cleaning liquid. Cleaning equipment. 2. The method according to claim 1, wherein the low frequency ranges from 20 KHz to 70 KHz.
2. The substrate cleaning apparatus according to claim 1, wherein the frequency is in a range of 0 KHz. 3. A substrate cleaning apparatus for cleaning a substrate by supplying a cleaning liquid provided with ultrasonic vibrations to the substrate, comprising: a support unit for supporting the substrate; A first nozzle that discharges a cleaning liquid to which ultrasonic vibration of a frequency is applied, and a second nozzle that discharges a cleaning liquid to which ultrasonic vibration of a relatively high frequency is applied toward a substrate supported by the support means A substrate cleaning apparatus comprising: 4. A substrate cleaning apparatus for cleaning a substrate by supplying a cleaning liquid provided with ultrasonic vibration to the substrate, comprising: a support means for supporting the substrate; and an ultrasonic vibration directed toward the substrate supported by the support means. A substrate cleaning apparatus comprising: a nozzle for discharging the applied cleaning liquid; and frequency switching means for switching the frequency of the ultrasonic vibration applied to the cleaning liquid to one of a relatively low frequency and a relatively high frequency. . 5. The method according to claim 1, wherein said low frequency is between 20 KHz and 700 KHz.
5. The substrate cleaning apparatus according to claim 3, wherein the high frequency is in a range of KHz, and the high frequency is in a range of 800 to 3000 KHz. 6. 6. The apparatus for cleaning a substrate according to claim 1, further comprising a high-pressure nozzle for discharging a cleaning liquid at a high pressure toward the substrate supported by the support means. 7. The substrate cleaning apparatus according to claim 1, further comprising a cleaning brush that abuts on a main surface of the substrate supported by the supporting means and brush-cleans the substrate. 8. A substrate cleaning method for cleaning a substrate by supplying a cleaning liquid to which ultrasonic vibration has been applied to a substrate, the method comprising: applying a relatively low frequency ultrasonic vibration to the cleaning liquid; Discharging the cleaning liquid toward the substrate at a flow rate sufficient to transmit the vibration into the cleaning liquid. 9. A method of cleaning a substrate by supplying a cleaning liquid to which ultrasonic vibration is applied to a substrate, comprising: discharging a cleaning liquid to which ultrasonic vibration of a relatively low frequency is applied toward the substrate; Discharging a cleaning liquid to which a relatively high frequency ultrasonic vibration is applied toward the substrate.