JP2006302974A - Apparatus for cleaning semiconductor wafer sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor wafer cleaning apparatus which has high cleaning effect, can save an operational cost and has a function of preventing bending of a wafer corresponding to a wafer size. <P>SOLUTION: A movable cap provided with a jetting nozzle moves down, covers a wafer to jet a liquid and clean the wafer, then, the moving cap moves above the wafer, and the wafer is transferred to a next station. A plurality of wafer supporting pillars provided in the individual station support the bottom of the wafer to prevent the bending of the wafer. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to an apparatus for cleaning a wafer surface in a horizontal position one by one by liquid ejection.

  As a conventional technique of this type, Patent Document 1 discloses a cleaning apparatus effective for preventing cracking of a wafer. In paragraph [0048], “Since the cleaning liquid can be sprayed from the top of the wafer, as shown in FIG. 10 (FIG. 9 of the present specification), in addition to the flux around the solder bump electrodes, fine solder debris is removed.” Are listed.

  The position of the cleaning nozzle shown in FIG. 10 (FIG. 9 in the present specification) is on the surface of the semiconductor wafer, directly above the solder bump of the sphere, and it is difficult to remove the flux at the base of the sphere. On the other hand, since the cleaning water is sprayed at a right angle, the cleaning area is narrow and the nozzles are scanned evenly to spray the cleaning liquid over the entire surface of the wafer. In the above disclosed technique, the wafer put in from the carry-in port moves in the direction of the arrow, and the cleaned wafer is taken out from the carry-out port and transferred to the next process. In the case of such an apparatus that takes time for cleaning, there is a disadvantage that the cleaning wafer conveyor becomes long and requires a large space and requires a large installation area, resulting in a large apparatus.

  As a further disadvantage, a lot of cleaning mist is generated and mist drifts out from the carry-in entrance and the carry-out exit, and is exhausted together with air through the exhaust duct. For this reason, the loss of the cleaning liquid has become a factor that increases the operating cost of this apparatus.

Japanese Patent Laid-Open No. 2003-7665, Name “Method of Manufacturing Semiconductor Device”

  Offers a cleaning device that has a high cleaning effect on solder waste and flux of semiconductor wafers, saves installation space, and saves operating costs. Corresponds to the trend toward larger wafer sizes and from 300μ to 100μ. It is an object of the present invention to cope with the diversification tendency of the thickness of the wafer, to improve the wafer deflection prevention, to improve the transfer means considering the damage of the wafer, and to improve the cleanliness in the cleaning and drying booth.

  A cleaning / rinsing process unit that has a movable cap that covers the semiconductor wafer, a cleaning liquid nozzle, and a rotating station on which the semiconductor wafer is fixedly mounted by a chuck, and one or more individual stations. And a drying process unit comprising a movable cap with a dry air supply pipe and a wafer holding turntable, a transfer control means and a transfer mechanism for simultaneously transferring semiconductor wafers with a tact time determined in conjunction with the vertical movement of the movable cap. A liquid pump including a cleaning liquid tank, a rinsing liquid tank, a liquid pump discharge adjusting means capable of adjusting a cleaning liquid and a rinsing liquid injection pressure and an injection liquid amount, and a liquid injection pressure and an injection liquid amount for each individual station. Are set to a predetermined value, and the rotation speed of the turntable is set to a predetermined setting value. When the relative speed between the nozzle and the turntable is changed and the optimum speed is found and set, the cleaning power is improved, the cleaning speed is improved, and from washing to rinsing can be performed in the same booth, and the drying process unit and tact time Was synchronized.

  A cleaning / drying unit that houses a single station consisting of a cleaning cap, a movable cap with a dry air supply pipe, and a wafer holder with an air supply tube, and performs all processes from cleaning to drying, and interlocks with the opening and closing operation of the movable cap In a cleaning apparatus having a driving means for transferring a semiconductor wafer to a subsequent process, a transfer control means, a cleaning liquid tank, and a rinsing liquid tank, a liquid pump discharge adjusting means and a liquid capable of adjusting the cleaning liquid and the rinsing liquid injection pressure, and each injection amount The apparatus includes a pump, an injection nozzle (and / or) wafer holding table rotational speed setting means, an injection angle setting means, an injection pressure setting means for each liquid, and an injection liquid amount setting means, and includes steps from cleaning to drying. The semiconductor wafer single wafer cleaning apparatus is characterized by being executed in one booth. This was realized by changing the relative speed between the nozzle and the turntable and improving the cleaning speed.

A movable cap provided with an injection nozzle is provided at each station so as to cover the wafer, and the injection direction of the injection nozzle can be adjusted within a range of 10 to 25 degrees with respect to the wafer surface. A semiconductor wafer single wafer cleaning device in which the liquid in each tank is guided to a nozzle by a liquid conduit through a liquid pump.

The wafer that has been transferred to the drying process unit at a predetermined tact time is fixed by a semiconductor that has a chuck holding mechanism (and / or) for chucking from the front and back on the side of the wafer and a vacuum suction means on the lower surface of the wafer. A wafer single wafer cleaning apparatus was obtained.
The wafers that have been transferred to the cleaning / rinsing process unit and the drying process unit all at the same tact time are fixed to the chuck holding mechanism (or / and) on the side of the wafer from the front and back. The semiconductor wafer single wafer cleaning apparatus is provided with a plurality of pillars supported by the lower surface to hold and prevent the wafer from bending.

  The semiconductor wafer single wafer cleaning apparatus is characterized in that the plurality of pillars supporting the wafer on the lower surface are pillars having top portions of horizontal surfaces on which the wafer plane is placed.

  The tops of the plurality of pillars that support the wafer on the lower surface have a vertical part or a top part of an inclined surface that is a part of a cone whose envelope surface opens upward, in the vicinity of the outer peripheral part of the horizontal surface on which the plane around the wafer is placed. A semiconductor wafer single wafer cleaning apparatus provided with wafer centering means for centering the wafer in contact with the outer peripheral side surface of the periphery of the wafer by the pillar group having the wafer.

  A dry air air supply tube that opens to the back surface of the wafer vacuum chucked (and / or) mechanically chucked on the spin table is provided, and is provided at an individual station so that a movable cap provided with the dry air air supply tube is covered. Single wafer cleaning of semiconductor wafers, characterized by blowing dry air at room temperature from the opening of the dry air supply pipe to the back and front surfaces of the semiconductor wafer and performing dry air drying instead of hot air drying to reduce the installation area of the cleaning device The device.

  Semiconductor wafer single wafer cleaning, characterized in that dry air is jetted onto the front surface (or / and back surface) of a semiconductor wafer fixed to a spin table, and at the same time, the spin table is rotated at a high speed to perform rapid drying together with centrifugal drying. The device.

A semiconductor wafer single wafer cleaning apparatus in which a loader unit as a means for placing a silicon wafer on a cleaning stage is connected to a unit having a cleaning function, and a side surface position of the unloader unit is connected to a unit having a drying function. .
Of the drive mechanism that transports semiconductor wafers, the components that are likely to be contaminated by lubricating oil are separated from the booth of the unit that has a cleaning and rinsing function. The configuration of the semiconductor wafer single wafer cleaning apparatus is characterized by increasing the degree.

  According to the present invention, since the cleaning speed is improved by changing the relative speed between the nozzle and the turntable, two conventional cleaning stations may be used, or one station from the cleaning to the rinsing process. It became possible. In this way, it can be manufactured in about 60% of the installation space of the conventional device, and the entire device can be manufactured in a light weight, small size and at a low cost. The cleaning liquid mist is collected and circulated, so that the amount of detergent consumed is small and the operating cost is low. In addition, it contributes to resource and energy savings by saving heat sources and has great industrial value.

  FIG. 1 is an overall configuration diagram of a first embodiment according to the present invention. 1A is a plan view, FIG. 1B is a front view, FIG. 1C is a side view, and FIG. 2 is a perspective view of the inside. FIG. 3 is an overall configuration diagram according to the second embodiment of the present invention. 3A is a plan view, FIG. 3B is a front view, FIG. 3C is a side view, and FIG. 8 is an overall configuration diagram of a conventional apparatus. The parts with the same symbols will be explained in common with each figure. A semiconductor wafer accommodated in a wafer magazine is set in the loader unit 1. The washing process unit 2, the rinsing process unit 3 and the drying process unit 4 are connected, and the loader unit 1 is connected to the inlet side, and the unloader unit 5 is connected to the side surface of the drying process unit 4 on the outlet side. The semiconductor wafer 11 is automatically operated by being transferred through an individual station 23 (shown in FIG. 2) from cleaning to drying. Equipped with transfer control means and transfer mechanism for transferring semiconductor wafers simultaneously at tact time, and equipped with cleaning liquid tank, rinsing liquid tank, cleaning liquid and liquid pump discharge adjusting means that can adjust the injection pressure and amount of rinsing liquid And a cleaning device in which the injection pressure and the amount of the injection liquid are set to predetermined values and the rotation speed of the spin table 28 (shown in FIG. 7) is set to a predetermined setting value for each individual station. . Of the drive mechanism that transports semiconductor wafers, the parts that are likely to be contaminated by lubricating oil are separated by separating them from the booth of the unit that has a cleaning and rinsing function with a separator to maintain the cleanliness in the booth. The wafer finished cleanliness is increased.

  The injection pressure gauge 29 is provided so that it can be seen from the outside of the main body, and while looking at the injection pressure of the liquid pump provided with the discharge adjusting means for sucking the liquid for washing and rinsing liquid freely and pressurizing it freely. The pressure is set to a predetermined pressure with a setting knob (not shown), but is set to a pressure / injection amount with a high cleaning power within a range not to be damaged according to the thickness dimension of the wafer. The size of the width W of the apparatus is determined by the demand for the cleaning tact time, and the number of cleaning process units 2 is determined. Compared with the conventional method using the wafer conveyor in FIG. Then, the width dimension could be shortened by 30%.

  FIG. 4 shows a main part of the cleaning process unit 2, which has a cap shaft 21 through which a liquid introduction pipe penetrates, and a movable cap 22 provided with an injection nozzle 16 is a semiconductor in an individual station 23 (shown in FIG. 2) Immediately after the wafer 11 is set, it descends downward to cover the wafer, and spray cleaning is performed for 30 seconds. The semiconductor wafer 11 was placed on the spin table 28 having the ten pillars 8 shown in FIG. 7, and the cleaning speed was increased by adding the relative speed to the spray nozzle 16.

  The surface of the semiconductor wafer 11 shown in FIG. 4 is provided with one or a plurality of spray nozzles 16 so that the entire surface is cleaned by the cleaning liquid sprayed from the spray nozzles 16. As a result of the experiment, the optimum value of the cleaning liquid injection angle θ from 16 was found. It has been found that for a semiconductor wafer having a diameter of 12 inches, there is an optimum value for the cleaning rate in the range of 15 ° ≦ θ ≦ 25 °. The spray nozzle 16 is formed so that the cleaning liquid spray angle θ can be swung freely or adjusted by adjusting the angle from 10 ° to 30 ° from the horizontal plane, and the case where the angle is set to 20 ° is most effective.

  The semiconductor wafer 11 is fixed by a chuck from the front and back on the side of the wafer so as not to be shaken by the inclined spray liquid 19. After completion of the cleaning, the movable cap 22 opens upward, and the semiconductor wafer 11 is picked up from the left and right by the chuck and transferred to the next station. During the period in which the movable cap 22 is opened upward, the wafer is removed from the previous process station. It is transferred to the next process station.

  The cleaning of one wafer is completed in about 30 seconds using a general-purpose detergent in the jet cleaning set in this way, and the wafer is moved to the next station 23. In the case of a single nozzle, it is effective to rotate the nozzle along the wafer circumference so that it is uniformly sprayed on the surface of the wafer. When there are a plurality of nozzles, the nozzle is rotated along the wafer circumference. No mechanism is required. The composite electrolytic ionic water is effective for both washing and rinsing.

  The effect of the movable cap 22 is that the spray of cleaning liquid generates mist during cleaning, and the cleaning liquid or the rinse liquid that has been discharged from the exhaust duct in the past is trapped in the cap and comes into contact with the cleaning or the rinse liquid. It has the effect of returning to the liquid. The effect of using the individual station 23 from the conventional method in which the wafer conveyor 14 is provided in a large cleaning tank contributes to the improvement of the environment in addition to the saving of the cleaning liquid and the rinsing liquid.

  The wafer is transferred to the next process station, and the wafer 11 is transferred to the cleaning process, the rinsing process, and the drying process one after another at a determined tact time. Since the discharge pressure adjusting means is provided in the liquid pump so that the injection pressure and the injection liquid amount of the cleaning and rinsing liquid can be set to be strong and weak, and a predetermined value is set for each station and can be monitored by the injection pressure gauge 29. The pressure on the wafer was too strong to break the wafer. Economical operations such as cleaning speed and water consumption are possible.

  The wafer 11 to which the wafer 11 has been transferred is fixed by chucking from the front and back, and cleaning and rinsing are performed. When the movable cap comes down on the wafer and the final rinse process is completed, the process proceeds to the spin drying process at the next station.

  FIG. 5 shows the internal configuration of the station of the drying process in the embodiment of the present invention. When the lower surface of the semiconductor wafer 11 is fixed by the vacuum suction means 30, the dry air 24 is supplied by the dry air supply pipe 26 penetratingly formed from the center of the movable cap 22, and the dry air 25 is also supplied by the dry air supply pipe 27 from below. At the same time, the spin table 28 is rotated by a motor, and spin drying is performed to shake off the liquid adhering to the wafer 11. This speed is controlled by the rotation control means so as to obtain a predetermined speed of up to 3000 rpm. It is also effective to provide a power frequency variable inverter for driving the motor so that the rotation speed can be set freely. The up-and-down movement of the movable cap, the spin operation, and the dry air ejection operation are executed by the interlock control means.

  FIG. 7 shows the structure of the wafer support in the embodiment of the present invention. If the diameter of the semiconductor wafer reaches 12 inches, the semiconductor wafer may bend, and the horizontal surface of the cleaning surface may be distorted and damaged. Therefore, ten pillars 8 for supporting the wafer are provided. The top shape of the pillar 8 is a horizontal surface portion 9 having a bank 10, and the back surface of the wafer 11 is supported by the horizontal surface 9. At the top of the pillar 8 is a bank 10 formed so that the wafer is held at the periphery. A pillar group having an inclined surface having a conical shape whose envelope surface opens upward or a vertical surface of the bank 10 has an effect of centering the wafer by contacting the wafer and moving to the water surface.

After the final rinse, the wafer is transferred to a spin table, which is a drying station, fixed by vacuum suction means, and blown with dry air for 30 seconds at a spin speed of 3000 rpm to complete centrifugal dehydration (spin drying). . The high-speed spin eliminates the need for conventional hot air supply and saves fuel and space for hot air generating means. The wafer after spin drying is transferred to the unloader unit 5 on the side surface and taken out.
The other embodiment shown in FIG. 3 has two booths, a washing and rinsing unit and a drying unit, which are dried on a drying stage while the washing and rinsing process is completed in the washing and rinsing unit 6, and the installation space is a conventional apparatus. Reduced by 40%.

  Residence time at the drying stage is achieved by spraying dry air onto the front surface (or / and back surface) of the semiconductor wafer 11 fixed to the spin table, and simultaneously rotating the spin table at a high speed to perform rapid drying together with centrifugal drying. Is greatly shortened, and the cleaning and rinsing process stage is dried until the entire process is processed in one stage. The cleaning nozzle 16, the movable cap 22 with the dry air supply pipe 26, and the wafer holding with the dry air supply pipe 27 are held. A loader unit 1 is connected to the entrance side of the unit in which only one station consisting of a table is accommodated, and all processes from cleaning to drying are performed, and an unloader unit 5 is coupled to the side surface on the exit side, so that the semiconductor wafer 11 is cleaned. Semiconductor wafer wafers that are automatically operated at one individual station 23 that processes until drying. Structure for realizing the purification device is also included in the present invention.

  In addition to reducing the installation space by 40% compared to conventional equipment, the equipment can be reduced in size and provided at low cost, and the loss of consumables required for operation has also been reduced. Conserving heat sources contributes to resource and energy savings and has great industrial value.

The whole block diagram in embodiment by this invention. The structural diagram of the principal part in embodiment by this invention. The whole block diagram in other embodiment by this invention. The structural diagram of the principal part in embodiment by this invention. The structural diagram of the principal part in embodiment by this invention. FIG. The structural diagram of the principal part in embodiment by this invention. The whole block diagram of the conventional apparatus. FIG. 3 is a schematic view of cleaning of a conventional apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Loader unit 2 Cleaning process unit 3 Rinsing process unit 4 Drying process unit 5 Unloader unit 6 Cleaning / rinsing process unit 8 Pillar 9 Horizontal surface part 10 Dike 11 Semiconductor wafer 14 Wafer conveyor 16 Injection nozzle
DESCRIPTION OF SYMBOLS 17 Carry-in port 18 Carry-out port 19 Inclined injection liquid 20 Exhaust duct 21 Cap shaft 22 Movable cap 23 Individual station 24 Dry air 25 Dry air 26 Dry air supply pipe 27 Dry air supply pipe 28 Spin table 29 Injection pressure gauge
30 Vacuum suction means

Claims (12)

One washing process unit, one rinsing process unit, which is a booth containing individual stations consisting of a cleaning nozzle, a movable cap, and a wafer holder, and an individual station consisting of a movable cap with an air feeding tube and a wafer holder It has a drying process unit, which is a booth, and is driven by a movable cap opening / closing operation. The drive means, transfer control means, cleaning liquid tank, rinsing liquid tank, cleaning liquid injection pressure and rinsing liquid injection pressure are used to transfer the semiconductor wafer to the subsequent process. And a liquid pump discharge adjusting means capable of adjusting each injection amount, a liquid pump as a constituent element, and a rotation speed setting means for an injection nozzle (and / or) wafer holder, which is set to a predetermined value. A semiconductor wafer single wafer cleaning device.
This is a booth in which a single station consisting of a cleaning nozzle, a movable cap and a wafer holding table is housed, and a single station consisting of a cleaning and rinsing process unit and a movable cap with a gas feed tube and a wafer holding table. Each having a drying process unit, driving means for transferring the semiconductor wafer to a subsequent process in conjunction with the opening and closing operation of the movable cap, a transfer control means, a cleaning liquid tank, a rinsing liquid tank, a cleaning liquid injection pressure, and a rinsing liquid injection pressure; A liquid pump discharge adjusting means capable of adjusting the injection amount, a liquid pump as a constituent element, a rotation speed setting means for an injection nozzle (and / or) wafer holder, and a predetermined value are set. Semiconductor wafer single wafer cleaning equipment.
A cleaning / drying unit that houses a single station consisting of a cleaning nozzle, a movable cap with an air supply tube, and a wafer holder with an air supply tube, and performs all processes from cleaning to drying. In a cleaning apparatus having a driving means for transferring a wafer to a subsequent process, a transfer control means, a cleaning liquid tank, and a rinsing liquid tank, a liquid pump discharge adjusting means and a liquid pump capable of adjusting the cleaning liquid and the rinsing liquid injection pressure and each injection amount, The apparatus includes a spray nozzle (and / or) wafer holding table rotational speed setting means, a spray angle setting means, a spray pressure setting means for each liquid, and a spray liquid amount setting means. A semiconductor wafer single wafer cleaning apparatus, which is executed at a booth.
A movable cap provided with an injection nozzle is provided at each station so as to cover the wafer, and the injection direction of the injection nozzle can be adjusted within a range of 10 to 25 degrees with respect to the wafer surface. 4. A semiconductor wafer single wafer cleaning apparatus according to claim 1, wherein the liquid in each tank is guided to a nozzle by a liquid guide pipe via a liquid pump.
The fixing of the wafer transferred to the drying process unit at a predetermined tact time includes a fixing mechanism (and / or) for chucking the chuck from the front and back on the side surface of the wafer, and a vacuum suction chuck on the lower surface of the wafer. Item 5. A semiconductor wafer single wafer cleaning apparatus according to Item 1.
The wafers that have been transferred to the cleaning / rinsing process unit and the drying process unit all at the same tact time are fixed to the chuck holding mechanism (or / and) on the side of the wafer from the front and back. 6. The semiconductor wafer single wafer cleaning apparatus according to claim 1, further comprising a plurality of pillars supported by the lower surface and holding the wafer while preventing the wafer from bending.
7. The semiconductor wafer single wafer cleaning apparatus according to claim 1, wherein the plurality of pillars supporting the wafer on the lower surface are pillars having top portions of horizontal surfaces on which the wafer plane is placed.
The tops of the plurality of pillars supporting the wafer on the lower surface are pillars having tops having vertical or inclined surfaces in the vicinity of the outer periphery of the horizontal surface on which the plane around the wafer is placed. 8. The semiconductor wafer single wafer cleaning apparatus according to claim 1, wherein the wafer is contacted and centered.
A dry air supply pipe that opens to the back surface of the wafer vacuum chucked (and / or) mechanically chucked on the spin table is provided, and is provided at an individual station so that a movable cap provided with the dry air supply pipe is covered. 9. Dry air drying is performed instead of hot air drying in order to blow dry air at room temperature from the opening of the dry air supply pipe to the back surface and front surface of the semiconductor wafer and to reduce the installation area of the cleaning device. The semiconductor wafer single wafer cleaning apparatus as described.
10. A dry air is jetted onto the front surface (or / and) the back surface of a semiconductor wafer fixed to the spin table, and at the same time, the spin table is rotated at a high speed to perform rapid drying together with centrifugal drying. The semiconductor wafer single wafer cleaning apparatus as described.
11. The semiconductor wafer single wafer cleaning apparatus cleaning apparatus according to claim 1, wherein a loader unit, which is a means for placing a silicon wafer on a cleaning stage, is connected to a unit having a cleaning function and has a drying function. A semiconductor wafer single wafer cleaning apparatus in which side surfaces of unloader units are connected.
  2. A drive mechanism for transferring a semiconductor wafer, wherein a member that is likely to be contaminated is isolated from the booth of a unit having a cleaning and rinsing function, and the cleanliness in the booth is maintained. The semiconductor wafer single wafer cleaning apparatus of thru | or 11.

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