JPH0864566A - Semiconductor wafer cleaning device - Google Patents

Abstract

PURPOSE: To execute effectively cleaning of semiconductor wafers by a method wherein in a semiconductor wafer cleaning device of a structure wherein a plurality of the semiconductor wafers held on a holding part are dipped in a cleaning liquid within a treating tank and contaminants adhered on the surfaces of the wafers are removed, a vibrating means for making the holding part vibrate is provided. CONSTITUTION: A plurality of semiconductor wafers 1 are held on a support part 6 in parallel to each other at prescribed intervals and are dipped in a cleaning liquid 4 within a treating tank. In this state, a high-frequency vibrating device 7 is actuated, high-frequency vibrations are generated, the high-frequency vibrations are propagated to the support part 6 via holding rods 8 and the high-frequency vibrations are given to the wafers 1 held on the support part 6. In such a way, as the wafers 1 themselves make the high-frequency vibrations, there is no attenuation of the vibrations due to a distance ranging from a vibration source to the wafers 1 and at the same time, a large fluid resisting force is obtained on the surfaces of the wafers 1 and the high cleaning effect of the wafers 1 is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor wafer cleaning apparatus, and more particularly to a vibrating means for vibrating a semiconductor wafer in a cleaning liquid.

[0002]

2. Description of the Related Art FIG. 9 is a sectional view showing a schematic structure of a conventional semiconductor wafer cleaning apparatus of this type. In the figure, 1 is a semiconductor wafer, 2 is a holder for holding the semiconductor wafer 1, 3 is a processing tank, 4 is a cleaning solution for the semiconductor wafer 1 contained in the processing tank 3, and is generally pure water or ammonia peroxide. An aqueous hydrogen solution or the like is used. Reference numeral 5 is a high-frequency oscillator having a vibrator portion 5a which is in contact with the bottom side of the processing tank 3 and oscillates at high frequency.

In the conventional semiconductor wafer cleaning apparatus having such a structure, a plurality of semiconductor wafers are held in parallel by the holding unit 2 at predetermined intervals and immersed in the cleaning liquid 4 in the processing tank 3. Since the cleaning liquid 4 is subjected to high-frequency vibration acceleration by the operation of the high-frequency oscillator 5, the surface of the semiconductor wafer in contact with the cleaning liquid 4 is effectively cleaned.

[0004]

Since the conventional semiconductor wafer cleaning apparatus is constructed as described above, the cleaning liquid 4 is subjected to high-frequency vibration acceleration, so that the semiconductor wafer 1 and the vibrator portion 5a are exposed. The cleaning effect decreases as the distance increases. Therefore, it is necessary to oscillate more than the required high frequency vibration. Further, the direction of vibration is determined by the mounting position of the vibrator 5a, that is, the direction of cleaning is limited. Further, at a high frequency vibration of 800 KHz or more, the directionality of the vibration wave is strong, so that cleaning unevenness occurs in the surface of the semiconductor wafer. That is, there is a problem that vibration is not transmitted to the concave and convex portions on the surface of the semiconductor wafer.

The present invention has been made to solve the above problems, and an object thereof is to obtain a semiconductor wafer cleaning apparatus in which cleaning is effectively performed and cleaning unevenness does not occur.

[0006]

[Means for Solving the Problems] Claim 1 according to the present invention
In the semiconductor wafer cleaning apparatus described above, a plurality of semiconductor wafers held by the holder are immersed in a cleaning liquid in a processing tank to remove contaminants adhering to the surface of the semiconductor wafer, and the holder is vibrated. The vibrating means is provided.

According to a second aspect of the present invention, in the semiconductor wafer cleaning apparatus of the first aspect, the vibrating means is a high-frequency vibrating device that vibrates at a high frequency.

According to a third aspect of the present invention, there is provided the semiconductor wafer cleaning apparatus according to the first aspect, wherein the vibrating means is a piston vibration generator that propagates vertical vibration to the holding portion by piston movement.

According to a fourth aspect of the present invention, in the semiconductor wafer cleaning apparatus according to the first aspect, the vibrating means is a disk-shaped rotating plate having an engaging pin protruding at a position deviated from the axis.
The rotation vibration generating device is formed by a retaining rod that propagates to the retaining portion the circular orbit of the engaging pin that is engaged with the engaging pin and moves by the rotation of the rotating plate.

According to a fifth aspect of the present invention, there is provided a semiconductor wafer cleaning apparatus in which a plurality of semiconductor wafers held by a holding portion are immersed in a cleaning liquid in a processing bath to remove contaminants adhering to the surface of the semiconductor wafer. The cleaning apparatus is provided with a vibrating means for vibrating the holding part and a liquid vibrating means for vibrating the cleaning liquid through the treatment tank.

According to another aspect of the semiconductor wafer cleaning apparatus of the present invention, the plurality of semiconductor wafers held by the holding portion are immersed in the cleaning liquid in the processing tank to remove contaminants adhering to the surface of the semiconductor wafer. The apparatus is provided with a vibrating unit that vibrates the holding unit and a rotating unit that rotates the semiconductor wafer in the holding unit.

According to a seventh aspect of the present invention, there is provided a semiconductor wafer cleaning apparatus having a mechanism for spraying a cleaning liquid while applying high-frequency vibration, and the cleaning liquid is sprayed on the surface of the semiconductor wafer held substantially horizontally by the holding portion to clean the surface. In the semiconductor wafer cleaning apparatus, the vibrating means for vibrating the holding part and accelerating the semiconductor wafer is provided.

According to an eighth aspect of the present invention, there is provided a semiconductor wafer cleaning apparatus according to any one of the first to fifth aspects, wherein the cleaning liquid is 4
It is pure water at a temperature of ℃ or less.

[0014]

The vibrating means of the semiconductor wafer cleaning apparatus according to the present invention vibrates the semiconductor wafer in the cleaning liquid via the holding portion holding the semiconductor wafer. Therefore, the semiconductor wafer is accelerated and accelerated without damaging the vibration. Causes a large fluid resistance force.

Further, in the high frequency vibration device of the semiconductor wafer cleaning device according to the present invention, the high frequency vibration is propagated to the semiconductor wafer without being attenuated because the semiconductor wafer is vibrated in the cleaning liquid at the high frequency through the holding part for holding the semiconductor wafer. It creates a large fluid drag force on the wafer surface.

Further, in the piston vibration generator of the semiconductor wafer cleaning apparatus according to the present invention, the semiconductor wafer is vertically vibrated like a piston in the cleaning liquid via the holding portion for holding the semiconductor wafer, so the vertical vibration is not damped. Is transmitted to the surface of the semiconductor wafer to generate a large fluid resistance force.

Further, in the rotational vibration generator of the semiconductor wafer cleaning apparatus according to the present invention, the vibration of the rotational movement along the circular orbit in the cleaning liquid is applied to the semiconductor wafer in the cleaning liquid via the holding portion for holding the semiconductor wafer without damaging the semiconductor wafer. It is propagated and causes a large fluid resistance force in all directions of the semiconductor wafer surface.

Further, the liquid vibrating means of the semiconductor wafer cleaning apparatus according to the present invention vibrates the cleaning liquid,
In addition to the direct vibration of the semiconductor wafer itself, a large fluid resistance force is generated on the surface of the semiconductor wafer.

Further, since the rotating means of the holding portion of the semiconductor wafer cleaning apparatus according to the present invention rotates the vibrating semiconductor wafer in the cleaning liquid, the semiconductor wafer itself is rotated, so that the surface of the semiconductor wafer is omnidirectionally vibrated. It improves the cleaning effect.

Further, the vibrating means of the semiconductor wafer cleaning apparatus according to the present invention vibrates the cleaning liquid at a high frequency to jet the cleaning liquid one by one, and when the surface of the semiconductor wafer is cleaned, the holding portion is vibrated to accelerate the semiconductor wafer itself. Let

Further, in the semiconductor wafer cleaning apparatus according to the present invention, the fluid resistance to the surface of the semiconductor wafer to be cleaned becomes large by using pure water of 4 ° C. or less as the cleaning liquid.

[0022]

【Example】

Example 1. Embodiment 1 of the present invention will be described below with reference to the drawings. 1 is a sectional view showing a schematic configuration of a semiconductor wafer cleaning apparatus according to Embodiment 1 of the present invention, and FIG. 2 is a side view taken along line II-II in FIG. In the figure, 1,
Since 3 and 4 are the same as the conventional ones, the description thereof will be omitted. Reference numeral 6 is a supporting portion for supporting the semiconductor wafer 1, 7 is a high-frequency vibrating device for generating high-frequency vibration by vibrating means, and 8 is a holding rod interposed between the supporting portion 6 and the high-frequency vibrating device 7 for propagating the high-frequency vibration to the supporting portion 6. 6 and 7, the holding part 9 is formed together with the supporting part 6.

Next, the operation will be described. A plurality of semiconductor wafers 1 are held in parallel at a predetermined interval on a support 6 and immersed in a cleaning liquid 4 in a processing bath 3. In this state, the high frequency vibration device 7 is operated to generate high frequency vibration and propagate the high frequency vibration to the support portion 6 via the holding rod 8. As a result, high frequency vibration is applied to the semiconductor wafer 1 held by the supporting portion 6. Since the semiconductor wafer 1 itself vibrates at high frequency in this way,
There is no attenuation of vibration due to distance from the vibration source as in the past,
At the same time, a large fluid resistance can be obtained on the surface of the semiconductor wafer, and a high cleaning effect can be obtained.

Example 2. Although the vibrating means is a high-frequency vibrating device in the first embodiment, as a second embodiment, as shown in FIG. 3, for example, a piston provided with a piston 10 driven by an engine, air, or the like and vertically swinging. Even if the vibration generator 11 is used as a vibrating means and the vertical amplitude movement of the piston 10 is propagated to the holding portion 9 to cause the semiconductor wafer 1 held by the support portion 6 to perform the vertical amplitude movement, the same effect as that of the first embodiment. Is obtained.

Example 3. The third embodiment of the present invention will be described below with reference to the drawings. Fourth Embodiment FIG. 4 is a sectional view showing a schematic configuration of a semiconductor wafer cleaning apparatus according to a third embodiment of the present invention.
In the figure, reference numerals 1, 3, 4, 6 are the same as those in FIG. Reference numeral 12 is a rotary plate that rotates around the shaft 12a and gives a circular orbit to the engaging pin 12b, and 13 is a holding rod in which one is engaged with the engaging pin 12b and the other is connected to the support portion 6,
These 12 and 13 form a rotary vibration generator 14.

Next, the operation will be described. A plurality of semiconductor wafers 1 are held in parallel at a predetermined interval on a support 6 and immersed in a cleaning liquid 4 in a processing bath 3. In this state, the shaft 12a
The rotating plate 12 rotates in the same manner as the rotating plate 12. As a result, the engagement pin 12b moves in a circular orbit, and the holding bar 13 engaged therewith also moves in the same orbit. Further, the supporting portion 6 connected to the holding rod 13 moves to give vibration to the held semiconductor wafer 1 due to the circular motion, and a fluid resistance larger than that in any direction is obtained on the surface of the semiconductor wafer 1 to enhance the contaminant removing ability. .

Example 4. Embodiment 4 of the present invention will be described below with reference to the drawings. FIG. 5 is a sectional view showing a schematic configuration of a semiconductor wafer cleaning apparatus in Embodiment 4 of the present invention.
In the figure, reference numerals 1, 3, 4, 6 to 8 are the same as those in FIG. Reference numeral 15 is a high-frequency vibrating portion of a liquid vibrating means which is provided on the bottom side of the processing tank 3 and applies high-frequency vibration to the cleaning liquid 4 via the processing tank 3. According to this structure, the cleaning liquid 4 vibrates in high frequency in addition to the high frequency vibration of the semiconductor wafer 1 itself, so that a larger fluid resistance force can be applied to the surface of the semiconductor wafer 1 and the cleaning effect is improved. In this case, it is desirable that both high frequencies have different phases so as to prevent uneven cleaning. Moreover, even if this configuration is applied to the second embodiment, the same effect can be obtained.

Example 5. Embodiment 5 of the present invention will be described below with reference to the drawings. FIG. 6 is a sectional view showing a schematic configuration of a semiconductor wafer cleaning apparatus in Embodiment 5 of the present invention.
In the figure, reference numerals 1, 3, 4 and 7 are the same as those in FIG. Reference numeral 16 is a rotation holding portion of a rotating means which supports a semiconductor wafer and is rotatably mounted by belt drive or the like (not shown), and 17 is interposed between the rotation holding portion 16 and the high frequency vibration device 7 and is a rotation holding portion. It is a holding rod holding 16.

Next, the operation will be described. A plurality of semiconductor wafers are held by the rotation holding unit 16 and immersed in the cleaning liquid 4 in the processing tank 3. In this state, the high frequency vibration device 7 operates to propagate the high frequency vibration to the semiconductor wafer 1 via the holding rod 17 and the rotation holding portion 16. At the same time, when a belt driving device (not shown) is operated to rotate the rotation holding unit 16 via a belt (not shown), the semiconductor wafer 1 contacting the outer circumference of the rotation holding unit 16 is rotated. Is. In this way, by rotating the semiconductor wafer 1 in response to the vertical amplitude vibration of the high frequency vibration, vibrations in all directions are given to the contaminants on the surface of the semiconductor wafer, and the contaminant removal capability is improved.

Example 6. Embodiment 6 of the present invention will be described below with reference to the drawings. FIG. 7 is a perspective view showing a schematic configuration of a semiconductor wafer cleaning apparatus in Embodiment 6 of the present invention.
Reference numeral 18 is a semiconductor wafer processed by a single wafer method (method for processing each wafer), 19 is a holding portion having a set pin 19a, 20 is a high-frequency vibrating device for generating high-frequency vibration by vibrating means, and 21 is a holding portion. A holding rod, which is interposed between the high frequency vibration device 20 and the high frequency vibration device 20, propagates the high frequency vibration. The mechanism 22 applies the high frequency vibration to the cleaning liquid 23 and ejects the cleaning liquid 23 onto the semiconductor wafer 18 (megasoscrub mechanism) (not shown).
It is a spray nozzle equipped with.

Next, the operation will be described. The semiconductor wafer 18 is set on the holder 19. By operating the high frequency vibration device 20 in this state, the high frequency vibration is generated by the holding rod 2.
1, propagated to the semiconductor wafer 18 via the holding unit 19. The cleaning liquid 23 is sprayed onto the semiconductor wafer 18 by the spray nozzle 22 while high-frequency vibration is applied to the semiconductor wafer 18. At this time, the spray nozzle 22 is uniformly moved within the surface of the semiconductor wafer. In this way, the spray nozzle 22 for injecting the cleaning liquid 23 with high frequency vibration and the semiconductor wafer 1
By combining the high frequency vibrating device 20 that vibrates 8 itself at high frequency, the cleaning effect is further enhanced. Further, in this case, since it is a single-wafer type (processing for each one), the mass of the object (semiconductor wafer, holding portion, etc.) can be reduced, and the acceleration (cleaning power) on the semiconductor wafer is increased.

The cleaning mechanism of Examples 1 to 6 will now be described in comparison with the conventional one. As a conventional example, liquid vibration (megasonic) has frequency f = 800 KHz and amplitude A =
When the fluid velocity V is 0.1 μm, V = Aω = A2πf = 0.1 × 10 ⁻⁶ · 2π · 800 ×
10 ³ = 0.5 m / sec. In the conventional cleaning by liquid vibration (megasonic), as shown in FIG. 8- (A), the liquid motion speed due to high frequency vibration becomes smaller as the surface becomes closer to the semiconductor wafer surface (h becomes smaller). According to the cleaning in the present invention, since the semiconductor wafer itself is vibrated, the contaminant itself on the surface directly receives the velocity due to the vibration, and the relative velocity between the contaminant and the cleaning liquid is large. FIG. 8- (B) shows that the closer to the surface of the semiconductor wafer (the smaller h is), the larger the relative motion velocity of the liquid due to the high frequency vibration of the semiconductor wafer. This means that the relative motion is represented by the following equation as a shear stress, and the greater this is, the greater the cleaning force becomes. τ = μV / h
(Unit: N / m ² = Pa). V: Fluid velocity h: Distance μ: Viscosity (determined by the type of fluid and temperature and pressure) Also, the external force (fluid resistance force) or cleaning force that particle-like contaminants (assumed to be spheres) are D = C _D ρ / 2 · V ² π / 4 · d ² _CD ; drag coefficient, ρ; liquid density, d; diameter of sphere Therefore, there is also a method of increasing ρ or μ to increase the external force (cleaning force). For example, if the cleaning liquid is pure water at 4 ° C. or 4 ° C. or lower than pure water at a constant temperature (about 20 ° C.) that is normally used, ρ or μ becomes large, so that the effect becomes remarkable. That is, in Examples 1 to 6, it is more effective to select a liquid equivalent to pure water as the cleaning liquid and having a specific gravity and viscosity higher than that of pure water.

[0033]

As described above, according to claim 1 of the present invention, a plurality of semiconductor wafers held by the holding portion are immersed in the cleaning liquid of the processing tank to remove contaminants adhering to the surface of the semiconductor wafer. In the semiconductor wafer cleaning device for removing, since the vibrating means for vibrating the holding portion is provided, there is an effect that a semiconductor wafer cleaning device capable of producing a high fluid resistance force on the surface of the semiconductor wafer and effectively cleaning can be obtained.

According to a second aspect of the present invention, in the first aspect, since the vibrating means is the high-frequency vibrating device that vibrates at a high frequency, the high-frequency vibration is propagated to the semiconductor wafer without being attenuated, and a large cleaning is performed on the surface of the semiconductor wafer. Generate force.

According to claim 3 of the present invention, in claim 1, the vibrating means is a piston vibration generator for propagating the vertical vibration to the holding portion by the mechanical piston movement. Propagated to the wafer, a large cleaning force is generated on the surface of the semiconductor wafer.

According to a fourth aspect of the present invention, in the first aspect, the vibrating means is a disc-shaped rotating plate having an engaging pin protruding at a position deviated from the axis, and an engaging pin. Since the circular vibration of the engaging pin that moves by the rotation of the rotating plate is formed by the holding rod that propagates to the holding portion, the vibration of the rotational movement along the circular path propagates to the semiconductor wafer. Then, a large cleaning force is generated in all directions on the surface of the semiconductor wafer.

According to a fifth aspect of the present invention, a semiconductor wafer cleaning process is performed in which a plurality of semiconductor wafers held by a holding unit are immersed in a cleaning liquid in a processing bath to remove contaminants adhering to the surface of the semiconductor wafer. Since the apparatus is provided with the vibrating means for vibrating the holding part and the liquid vibrating means for vibrating the cleaning liquid through the processing tank, the cleaning liquid vibrates in addition to the vibration of the semiconductor wafer itself, and a larger cleaning power is applied to the surface of the semiconductor wafer. Give rise to.

Further, according to claim 6 of the present invention, a semiconductor wafer cleaning is performed in which a plurality of semiconductor wafers held by the holding portion are immersed in a cleaning liquid in a processing tank to remove contaminants adhering to the surface of the semiconductor wafer. In the apparatus, since the vibrating means for vibrating the holding part and the rotating means for rotating the semiconductor wafer are provided in the holding part, omnidirectional vibration is given to the surface of the semiconductor wafer, and the cleaning effect is improved.

Further, according to claim 7 of the present invention, a cleaning liquid is sprayed onto the surface of the semiconductor wafer held substantially horizontally by the holding portion, which is provided with a mechanism for spraying the cleaning liquid while applying high-frequency vibration. In the semiconductor wafer cleaning apparatus for performing the above, since the vibrating means for vibrating the holding portion and accelerating the semiconductor wafer is provided, the semiconductor wafer itself also performs the accelerating motion to increase the cleaning power of the surface of the semiconductor wafer.

According to the eighth aspect of the present invention, in any one of the first to fifth aspects, the cleaning liquid is pure water at 4 ° C. or lower, so that the fluid resistance against the surface of the semiconductor wafer becomes large and cleaning is performed. Improve power.

[Brief description of drawings]

FIG. 1 is a sectional view showing a schematic configuration of a semiconductor wafer cleaning apparatus according to a first embodiment of the present invention.

FIG. 2 is a side view taken along the line II-II in FIG.

FIG. 3 is a sectional view showing a schematic configuration of a semiconductor wafer cleaning apparatus according to a second embodiment of the present invention.

FIG. 4 is a sectional view showing a schematic configuration of a semiconductor wafer cleaning apparatus according to a third embodiment of the present invention.

FIG. 5 is a sectional view showing a schematic configuration of a semiconductor wafer cleaning apparatus according to a fourth embodiment of the present invention.

FIG. 6 is a sectional view showing a schematic configuration of a semiconductor wafer cleaning apparatus according to a fifth embodiment of the present invention.

FIG. 7 is a sectional view showing a schematic configuration of a semiconductor wafer cleaning apparatus according to a sixth embodiment of the present invention.

8A and 8B are explanatory views of a cleaning mechanism, where FIG. 8A shows a conventional case and FIG. 8B shows a case of the present invention.

FIG. 9 is a schematic configuration diagram of a conventional semiconductor wafer cleaning apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 semiconductor wafer, 3 processing tank, 4 cleaning liquid, 7 high-frequency vibrating device (vibrating means), 9 holding part, 11 piston vibration generating device (vibrating means), 12 rotary plate, 12b engaging pin, 13 holding rod, 14 rotational vibration Generator (vibrating means), 15 high frequency vibrating section (liquid vibrating means), 16 rotation holding section (rotating means), 18 semiconductor wafer, 19 holding section, 20 high frequency vibrating apparatus (vibrating means), 22 spray nozzle with high frequency vibrating section, 23 Cleaning liquid to be sprayed under high frequency vibration.

Claims (8)

[Claims] 1. A semiconductor wafer cleaning device for immersing a plurality of semiconductor wafers held by a holding unit in a cleaning liquid of a processing tank to remove contaminants adhering to the surface of the semiconductor wafer, and vibrating the holding unit. A semiconductor wafer cleaning device comprising a vibrating means. 2. The semiconductor wafer cleaning apparatus according to claim 1, wherein the vibrating means is a high-frequency vibrating device that vibrates at a high frequency. 3. The semiconductor wafer cleaning apparatus according to claim 1, wherein the vibrating means is a piston vibration generator that propagates vertical vibration to the holding portion by piston movement. 4. The vibrating means is a disk-shaped rotating plate having an engaging pin protruding at a position deviated from the axis, and the engaging member engaging with the engaging pin and moving by rotation of the rotating plate. 2. The semiconductor wafer cleaning device according to claim 1, wherein the semiconductor wafer cleaning device is a rotary vibration generating device formed of a holding rod that propagates a circular orbit of a pin to a holding portion. 5. A semiconductor wafer cleaning apparatus for immersing a plurality of semiconductor wafers held by a holding unit in a cleaning liquid of a processing tank to remove contaminants adhering to the surface of the semiconductor wafer, wherein the holding unit is vibrated. An apparatus for cleaning a semiconductor wafer, comprising: a vibrating unit; and a liquid vibrating unit that vibrates the cleaning liquid through the processing bath. 6. A semiconductor wafer cleaning apparatus for immersing a plurality of semiconductor wafers held by a holding unit in a cleaning liquid of a processing tank to remove contaminants adhering to the surface of the semiconductor wafer, wherein the holding unit is vibrated. An apparatus for cleaning a semiconductor wafer, comprising: a vibrating means; and a rotating means for rotating the semiconductor wafer in the holder. 7. A semiconductor wafer cleaning apparatus comprising a mechanism for spraying a cleaning liquid while applying high-frequency vibration, and spraying the cleaning liquid onto the surface of a semiconductor wafer held substantially horizontally in a holder to clean the surface. An apparatus for cleaning a semiconductor wafer, comprising: a vibrating unit that vibrates the holding unit to accelerate the semiconductor wafer. 8. The semiconductor wafer cleaning apparatus according to claim 1, wherein the cleaning liquid is pure water at 4 ° C. or lower.