JPH11239974A - Sandblast device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide uniform sandblast treatment by suppressing the influence of load fluctuation even if a nozzle is reciprocated. SOLUTION: This sandblast device is to apply blast treatment to a base board by injecting abrasive material to the base board, and is equipped with a carrier conveyer 31, injection nozzles 64, 65, support arms 60, 61 and a motor 32 and crank mechanisms 40, 50 to reciprocate the support arms 60, 61. The crank mechanisms 40, 50 are equipped with rotating arms 41, 51 and connecting arms 42, 52 respectively, and connecting points 42a, 52a of the connecting arms 42, 52 are shifted each other from symmetric positions of 180 deg. on a rotation locus C of the rotating arm 41.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sand blasting apparatus for blasting a substrate to be processed by spraying an abrasive onto the substrate.

[0002]

2. Description of the Related Art Generally, abrasive is sprayed on the back surface of a substrate to be processed such as a semiconductor wafer to give a distortion, thereby providing
Collecting impurities in the crystal on the back side of the substrate
Sandblasting for backside gettering is known.

In a sand blasting apparatus for performing the above sand blasting process, conventionally, an abrasive is ejected by swinging an ejection nozzle.

However, according to such an injection method, the tip of the injection nozzle swings like a cradle in the width direction of the substrate to be processed. In this case, the gap between the injection nozzle tip and the substrate surface is different between the center and the end of the substrate to be processed, the angle between the injection nozzle and the substrate is different between the center and the end of the substrate to be processed, For this reason, there is a drawback that uniform sandblasting cannot be expected over the entire width direction of the substrate to be processed. In other words, the gap between the tip of the injection nozzle and the substrate surface is small, and the central part of the substrate where the injection nozzle and the substrate are orthogonal to each other has a stronger sandblasting process, the gap between the tip of the injection nozzle and the substrate surface is larger, and The sand blast processing is weaker at the end of the substrate where the substrate is inclined.

[0005] Therefore, there has been a demand for a sand blasting device that horizontally reciprocates the injection nozzle without swinging the injection nozzle. Such a sandblasting device is disclosed in Japanese Patent Application Laid-Open No. Hei 5-116070.

FIG. 6 is a diagram described in the above-mentioned publication, in which reference numeral 11 denotes a semiconductor wafer, 12 denotes a horizontal transfer path, 13 denotes an injection nozzle, 14a denotes a support rod for supporting the nozzle, and 17 denotes a support rod. Bearing, 20 is a cam mechanism, 21 is an arm part for converting eccentric rotation into linear motion, 23 is an eccentric cam part which is formed in a perfect circle and a shaft 23a is fixed at a position eccentric from the center of the perfect circle, 26 is a pulley, 27 is a belt, 28 is a motor.

When the motor 28 is driven with this configuration, the shaft 23a rotates, and the eccentric cam portion 23 performs eccentric rotation. This eccentric rotation is converted by the arm 21 into a reciprocating linear movement of the support rod 14a. In this way, a horizontal reciprocating movement of the injection nozzle 13 is provided.

[0008]

However, in the above-mentioned conventional sandblasting apparatus, the moving speed is maximum near the center of the reciprocating movement, and becomes zero at the time of reversal. In other words, there is a problem that the load fluctuates with time depending on the moving location, and uniform sandblasting cannot be expected.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a sandblasting apparatus capable of performing uniform sandblasting by suppressing the influence of load fluctuation even when the nozzle is reciprocated. Aim.

[0010]

According to a first aspect of the present invention, there is provided a sand blasting apparatus for blasting a substrate to be processed by injecting an abrasive to the substrate. Transfer means for transferring the processing substrate, an injection nozzle arranged above the transfer means and for jetting an abrasive to the substrate to be processed, a support arm for supporting the injection nozzle, and the support arm For reciprocating in a direction perpendicular to the direction of transport of the substrate to be processed, a rotation drive mechanism and a crank mechanism,
The crank mechanism is configured to include a rotating arm coaxially connected to a rotation axis of the rotation drive mechanism, and a connection arm connecting the rotation arm and the support arm, A plurality of crank mechanisms are provided, and the connecting points of the connecting arms of the crank mechanisms with respect to the rotary arm are shifted from the 180 ° symmetrical position on the rotation trajectory of the rotary arm in plan view with a position shifted from each other. It is characterized by being. In the sandblasting device according to claim 2, in the sandblasting device according to claim 1, the support arm is movably supported by a device frame via a ball bush, and around the support arm, A bellows is provided for isolating a portion of the support arm between the fixed portion of the injection nozzle and a portion supported by the ball bush. In the sand blasting device according to claim 3,
3. The sandblasting device according to claim 2, wherein the support arm is provided with a hollow cylinder portion, and at least one of the support arms communicates the inside and outside of the hollow cylinder portion with a portion surrounded by the bellows. It is characterized in that two ventilation holes are formed, and the opposite end of the support arm is configured to be capable of sucking and discharging. In the sand blasting device according to claim 4, in the sand blasting device according to any one of claims 1 to 3, the injection nozzle is fixed to the support arm in a state of being angularly oriented from a perpendicular direction with respect to the conveyance unit. It is characterized by being.

The rotation of the rotary arm is converted into a reciprocating movement of the support arm by the crank mechanism. Here, when the connection point of the connection arm of the connection arm of a certain crank mechanism to the rotation arm and the connection point of the connection arm of the other crank mechanism are at 180 ° symmetrical positions on the rotation trajectory of the rotation arm in plan view. The reversal timing of the reciprocation by one crank mechanism is the same as the reversal timing of the reciprocation by the other crank mechanism, and the effect of the load fluctuation is doubled. On the other hand, according to the first aspect of the present invention, the connecting point of the connecting arm of a certain crank mechanism to the rotating arm and the connecting point of the connecting arm of another crank mechanism are defined by the rotation locus of the rotating arm in plan view. Since the positions are shifted from the above 180 ° symmetrical position, the reversal timing of the reciprocation by one crank mechanism and the reversal timing of the reciprocation by the other crank mechanism deviate from each other. Therefore, the load fluctuation by one crank mechanism and the load fluctuation by the other crank mechanism deviate in time, and the load fluctuation is averaged over time. Therefore, even if the nozzle is reciprocated, the effect of load fluctuation is suppressed, and uniform sandblasting is provided. According to the second aspect of the present invention, since the bellows are provided around the support arm, the abrasive near the injection nozzle does not scatter to the ball bush and bite into the ball bush.
Also, machine oil and dust near the ball bush scatter,
It is prevented from falling around the injection nozzle, that is, around the substrate to be processed. According to the third aspect of the present invention, the support arm is provided with the hollow cylindrical portion, and at least one ventilation hole for communicating the inside and the outside of the hollow cylindrical portion is formed in a portion surrounded by the bellows. Have been. The opposite end of the support arm is configured to be able to freely suck and exhaust. Therefore, when attention is paid to the space between the bellows and the outer surface of the hollow cylinder, the air in this space passes through the air hole and the hollow portion of the support arm, and communicates with the opposite end of the support arm that is made freely suckable and exhaustable. I have. As a result, the space between the bellows and the outer surface of the hollow cylinder can freely be sucked and exhausted. Therefore, with the reciprocating movement of the support arm, the volume of the space between the bellows and the outer surface of the hollow cylinder changes, and even if a pressure change is likely to occur in this space, the space has passed through the air hole and the hollow portion of the support arm. Due to the ventilation, no pressure change occurs in this space. This results in a smooth expansion and contraction movement of the bellows. According to the fourth aspect of the present invention, since the spray nozzle is fixed to the support arm in a state where the spray nozzle is oriented at an angle from the orthogonal direction with respect to the transport means, the abrasive sprayed from the spray nozzle causes the substrate to be processed or the transport means. Even if it bounces off, this bounce goes in a direction deviating from the injection nozzle and does not head toward the injection nozzle. Therefore, the effect of the rebound of the abrasive is prevented.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a sandblasting apparatus according to an embodiment of the present invention.

FIG. 1 shows an embodiment of a sand blasting apparatus according to the present invention. FIG. 1 is a plan view, FIG.
FIG. 3 shows a left side view.

As shown in the figure, the sand blasting apparatus of the present invention comprises an apparatus frame 30, a conveyor (transporting means) 31, a motor (rotation drive mechanism) 32, an upper crank mechanism (crank mechanism) 40, and a lower crank mechanism ( Crank mechanism) 50, support arms 60, 61, bellows 62, 6
3, the injection nozzles 64, 65, and the like.

The conveyor 31 transfers a substrate to be processed (not shown) such as a semiconductor wafer, for example, in a direction indicated by an arrow A in FIG.
It is for transporting and is installed horizontally.

The motor 32 is for rotating and driving a rotating shaft 32a arranged in a vertical direction.

The upper crank mechanism 40 includes a rotary arm 41 having one end 41a rotatably mounted on a rotary shaft 32a of the motor 32, and a connection rotatably mounted on the rotary arm 41 at a connection point 42a. And an arm 42.

The lower crank mechanism 50 includes a rotating arm 51
And a connecting arm 52 rotatably attached to the rotating arm 51 at a connecting point 52a. In this case, the rotating arm 51
One end is rotatably mounted at a connection point 42a and the other end is connected to an auxiliary arm 53 rotatably mounted at a connection point 52a, and is rotatably supported on a shaft 51a. Thus, the rotary arm 51 is driven to rotate coaxially with the rotary shaft 32a.

In this case, the connecting points 42a, 52a of the connecting arms 42, 52 of the crank mechanisms 40, 50 with respect to the rotating arms 41, 51 are defined by the rotation trajectory C of the rotating arms 41, 51 in plan view (FIG. 1). Above, they are arranged with an opening angle of about 120 ° (ie, with an opening angle offset from the 180 ° symmetry position). Here, FIG. 1 is different from FIG.
It should be noted that 1, 51 are shown with a slight rotation of clockwise in the figure.

The support arm 60 is supported by the apparatus frame 30 via a ball bush 60a so as to be reciprocally movable in a direction perpendicular to the direction of transport of the substrate to be processed (A direction). The support arm 60 is configured by integrally combining three members each holding the injection nozzle 64. The support arm 60 is connected to the connecting arm 42 via a rotatable shaft 60b.

Similar to the support arm 60, the support arm 61 is supported by the apparatus frame 30 via a ball bush 61a so as to be reciprocally movable in a direction orthogonal to the transport direction (A direction) of the substrate to be processed. ing. Support arm 6
Reference numeral 1 denotes a structure in which three nozzles each holding an injection nozzle 65 are integrally connected. In addition, the support arm 6
1 is a shaft 6 rotatable with respect to the connecting arm 52.
1b.

Upper crank mechanism 40 and support arm 60
According to the configuration described above, the rotational movement of the rotary arm 41 by the rotational drive of the motor 32 can be converted into the reciprocating movement of the support arm 60.

Similarly, based on the configuration of the lower crank mechanism 50 and the support arm 61, the rotational movement of the rotary arm 51 by the rotation of the motor 32 can be converted into the reciprocating movement of the support arm 61.

The bellows 62, 63 are provided with support arms 60,
In order to isolate between the fixed portions of the injection nozzles 64 and 65 of 61 and the portions supported by the ball bushes 60a and 60b, they are disposed around the support arms 60 and 61, respectively.

Here, the configuration of the support arm and the bellows will be described in more detail by taking the support arm 61 and the bellows 64 as an example and referring to FIG.

The support arm 61 is formed of a hollow cylinder as shown in FIG.
Is slidably supported via the bearing 61b.
And, in the part surrounded by the bellows 63,
A plurality of ventilation holes 61c are formed. As shown schematically in FIG. 2, various members are screwed to the open end of the opposite end of the support arm 61. In other words, the open end at the opposite end of the support arm 61 is not air-tight, but is configured to be able to freely suck and discharge air. In this case, it goes without saying that an intake / exhaust unit that performs intake / exhaust at the same time as the reciprocating movement of the support arm 61 may be connected to the opposite end of the support arm 61. Although description and illustration are omitted, the support arm 60 and the bellows 62 have the same configuration.

The injection nozzles 64 and 65 are for injecting an abrasive to the substrate to be processed.
It is fixed to the support arms 60 and 61 via links 64a and 65a. As shown in FIG. 3, the injection nozzles 64 and 65 are inclined about 10 ° from the vertical line toward the upstream side in the transport direction (A direction) above the transport conveyor 31 (that is, the transport conveyor 31). 31 (in a state of being angularly oriented from an orthogonal direction). An abrasive supply line 66 and a compressed air supply line 67 are connected to each of the injection nozzles 64 and 65.

In the sand blasting apparatus configured as described above, the rotating motion of the rotating arms 41 and 51 is controlled by the crank mechanisms 40 and 50 so that the supporting arms 60 and 6 rotate.
1 is converted into a reciprocating movement in a direction orthogonal to the substrate transfer direction (A direction). That is, the injection nozzles 64, 65
Is reciprocated in a direction orthogonal to the substrate transport direction (A direction). Here, the connection point 42 of the connection arm 42 of the upper crank mechanism 40 with respect to the rotation arm 41
a and a connection point 52a of the connection arm 52 of the lower crank mechanism 50 with respect to the rotation arm 51 are 18 points on the rotation locus C of the rotation arms 41 and 51 in plan view.
Since the positions are shifted from the 0 ° symmetry position,
The reversal timing of the reciprocation by the upper crank mechanism 40 and the reversal timing of the reciprocation by the lower crank mechanism 50 are shifted. Therefore, the upper crank mechanism 4
The load fluctuation due to 0 and the load fluctuation due to the lower crank mechanism 50 are temporally shifted, and the load fluctuation is averaged over time. Therefore, the nozzle 64,
Even if 65 is reciprocated, the effect of load fluctuation is suppressed, and uniform sandblasting is provided.

In the case of the conventional configuration, the motor capacity must be increased in order to maintain a constant rotational speed, despite the fact that the load fluctuates greatly and the starting torque is small. On the other hand, in the present invention, by shifting the arm mounting position of the crank mechanism from the symmetrical position, the rotational balance is deteriorated, but the load fluctuation is reduced. can do.

Next, an example of the sandblasting process in the present invention will be described with reference to FIG. In FIG.
The movement locus 76 of the ejection nozzle with respect to the semiconductor wafer (substrate to be processed) 75 and the relationship between the movement speed of the ejection nozzle and the position in the width direction are shown. In the illustrated example, a portion F where the moving speed of the injection nozzle is relatively high is used for the actual blasting process, except for a portion E where the moving speed of the injection nozzle is relatively low with respect to the entire blast range D. This achieves relatively uniform sandblasting.

As shown in FIG.
The reciprocating movement speed of the nozzle is kept constant so that the interval G between the movement trajectories of the injection nozzles in the transfer direction (A direction) is sufficiently small (strictly speaking, as shown in FIG. By making the transfer speed of the semiconductor wafer 75 variable while keeping the reciprocating speed pattern constant,
The amount of damage to the wafer is determined. Although not limited, for example, the wafer transfer speed is set to 10 mm / s to 50 mm / s for a reciprocating movement pattern of the nozzle of 100 reciprocations / min (maximum value).

In this case, a control method for making the nozzle reciprocating speed pattern variable while keeping the wafer transfer speed constant may be used. However, the control method for making the nozzle reciprocating speed pattern constant as described above is employed. This is because the torque characteristics of the motor 32 are considered. In other words, the rotational speed region where the torque is the largest (for example, 1800
This is due to the fact that the motor 32 is rotated at a constant speed at about 1200 rpm (in the case of a rpmMMAX motor). By doing so, the influence of the load fluctuation on the motor 32 is further suppressed, and the stability of the nozzle reciprocating speed can be improved.

Further, since the bellows 62, 63 are provided around the support arms 60, 61, the abrasive material near the injection nozzles 64, 65 can be used for the ball bushes 60a, 6a.
It does not fly to 1a and bite into the ball bushes 60a, 61a. Also, ball bushes 60a, 61a
The nearby machine oil and dust are scattered, and the spray nozzles 64, 65
It is prevented from falling around, that is, around the substrate to be processed.

Normally, the bellows are formed with air holes for the purpose of preventing pressure fluctuation due to expansion and contraction. However, in the bellows 62, 63 of the present embodiment, the injection nozzle 64,
No air holes are provided to ensure the separation between the fixed portion 65 and the supporting portion by the ball bushes 60a, 60b. In the present embodiment, instead of providing such air holes, the support arms 60 and 61 are formed of hollow cylinders, and the ventilation holes 61c are provided. Further, the opposite ends of the support arms 60 and 61 are configured so as to be capable of sucking and discharging. Thereby, the space 80 between the bellows and the outer surface of the hollow cylinder can be communicated with the opposite end of the support arm 61 which can freely suck and exhaust through the vent hole 61c and the hollow portion of the support arm 61. Therefore, even if the volume of the space between the bellows and the outer surface of the hollow cylinder changes with the reciprocating movement of the support arm 61 (indicated by a double arrow B in FIG. 4), the ventilation hole and the support arm The ventilation through the hollow part (indicated by the arrow C in FIG. 4) can be performed, so that no pressure change occurs in this space 80. Thereby, smooth expansion and contraction movement of the bellows 63 can be secured.

Further, since the spray nozzles 64 and 65 are fixed to the support arms 60 and 61 in a state where the spray nozzles 64 and 65 are angularly oriented from the orthogonal direction with respect to the conveyor 31, the abrasive material sprayed from the spray nozzles 64 and 65 is If the bounces off from the substrate to be processed or the conveyor 31, the bounces are directed in a direction deviating from the injection nozzles 64 and 65, and do not reach the injection nozzles 64 and 65. Therefore, the effect of the rebound of the abrasive is prevented.

It should be noted that the present invention is not limited to the above-described embodiment, but may be configured as follows. a) Use a substrate to be processed other than a semiconductor wafer. b) The transfer speed of the substrate to be processed, and the injection nozzle 64
Set the reciprocating speed of 65 arbitrarily. c) In the lower crank mechanism 50, instead of using the rotating arm 51 that rotates in conjunction with the rotating arm 41 via the auxiliary arm 53, a rotating arm directly attached to the rotating shaft 32a of the motor 32 is used. thing. d) The angle of inclination of the injection nozzles 64 and 65 from the vertical line is 1
Instead of 0 °, an arbitrary inclination angle should be set.

[0037]

According to the sandblasting device of the present invention,
The following effects are obtained. According to the sandblasting device of the first aspect, the connection point of the connection arm of the certain crank mechanism to the rotation arm and the connection point of the connection arm of the other crank mechanism are defined by 180 degrees on the rotation trajectory of the rotation arm in plan view.の Since the positions are shifted from the symmetric position, the reversal timing of the reciprocal movement by one crank mechanism and the reversal timing of the reciprocal movement by the other crank mechanism can be shifted.
The load fluctuation by one crank mechanism and the load fluctuation by another crank mechanism can be shifted in time, and the load fluctuation can be averaged in time. Therefore,
Even if the nozzle is reciprocated, uniform sandblasting can be performed while suppressing the effect of load fluctuation. According to the sand blasting device of the second aspect, the bellows provided around the support arm can prevent the abrasive material near the injection nozzle from scattering to the ball bush and prevent the abrasive material from getting into the ball bush. Also,
It is possible to prevent mechanical oil and dust near the ball bush from scattering and falling around the injection nozzle, that is, around the substrate to be processed. According to the sand blasting device of the third aspect, the support arm includes the hollow cylindrical portion, and at least one ventilation hole for communicating the inside and outside of the hollow cylindrical portion with the portion surrounded by the bellows. Is formed, and the opposite end of the support arm is configured to be capable of suction and exhaust, so that the space between the bellows and the outer surface of the hollow cylinder can be freely suctioned and exhausted through the ventilation hole and the hollow portion of the support arm. Can be communicated with the opposite end of the support arm. Therefore, even if the volume of the space between the bellows and the outer surface of the hollow cylinder changes due to the reciprocating motion of the support arm, it is possible to perform ventilation through the ventilation hole and the hollow portion of the support arm, so that pressure is applied to this space. There is no change. Thereby, smooth expansion and contraction movement of the bellows can be ensured. According to the sand blasting device of the fourth aspect, since the spray nozzle is fixed to the support arm in a state of being angularly oriented from the orthogonal direction with respect to the conveying means, the abrasive sprayed from the spray nozzle rebounds and is sprayed. It is possible to prevent heading to the nozzle.

[Brief description of the drawings]

FIG. 1 is a plan view showing one embodiment of a sandblasting device of the present invention.

FIG. 2 is a front view of the sandblasting apparatus shown in FIG.

FIG. 3 is a left side view of the sandblasting apparatus shown in FIG.

4 is an enlarged front view showing a part of the sandblasting apparatus shown in FIG. 1;

FIG. 5 is an explanatory diagram showing an example of a sandblasting process according to the present invention.

FIG. 6 is a side view showing an example of a conventional sandblasting device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 30 Device frame 31 Conveyor for conveyance (conveying means) 32 Motor (rotation drive mechanism) 32a Rotating shaft 40 Upper crank mechanism (crank mechanism) 41 Rotation arm 42 Connection arm 42a Connection point 50 Lower crank mechanism (crank mechanism) 51 Rotation arm 52 Connection arm 52a Connection point 60 Support arm 60a Ball bush 61 Support arm 61a Ball bush 61c Vent 62 Bellows 63 Bellows 64 Injection nozzle 65 Injection nozzle 75 Semiconductor wafer (substrate to be processed) C Rotation locus

Claims (4)

[Claims] 1. A sand blasting apparatus for blasting a substrate to be processed by injecting an abrasive onto the substrate to be processed, comprising: a transporting unit for transporting the substrate to be processed; A spray nozzle for spraying an abrasive on the substrate to be processed and a support arm for supporting the nozzle, and reciprocating the support arm in a direction orthogonal to a transport direction of the substrate to be processed. A rotary drive mechanism and a crank mechanism for moving, the crank mechanism comprising: a rotary arm connected coaxially with a rotary shaft of the rotary drive mechanism; and the rotary arm and the support arm. And a connecting arm for connecting, the plurality of crank mechanisms being provided, and connecting each connecting arm of the crank mechanism to the rotating arm. Into each other is, in a plan view, sandblasting apparatus characterized by from 180 ° symmetrical positions on the rotation locus of the rotary arm, there is a position shifted from each other. 2. The sandblasting device according to claim 1, wherein said support arm is movably supported by a device frame via a ball bush, and said support arm is provided around said support arm. A bellows for isolating between a fixed portion of the injection nozzle and a portion supported by the ball bush. 3. The sand blasting device according to claim 2, wherein the support arm includes a hollow cylindrical portion, and a portion surrounded by the bellows includes:
A sand blasting device, wherein at least one ventilation hole for communicating the inside and the outside of the hollow cylindrical portion is formed, and the opposite end of the support arm is configured to be capable of sucking and discharging. 4. The sandblasting device according to claim 1, wherein the injection nozzle is fixed to the support arm in a state where the injection nozzle is angularly oriented from an orthogonal direction with respect to the transporting unit. Characteristic sandblasting equipment.