JP5312662B1 - Wafer rotating apparatus and wafer rotating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wafer rotating device capable of rotating a wafer in a processing tank without generating fine dust in order to eliminate processing unevenness of the wafer.
SOLUTION: A processing liquid tank 2 for storing a processing liquid and capable of immersing a wafer in the processing liquid; and a lower intermediate portion of the wafer W is held in the processing liquid tank 2 along the surface of the wafer. The wafer pedestal 6 configured to be swingable in the direction and the wafer pedestal 6 in the processing liquid tank 2 are disposed so as to sandwich the wafer pedestal 6, and move vertically relative to the wafer pedestal 6 to move the wafer. A pair of wafer guides 7 configured to be able to hold both lower ends of the wafer, and the wafer holder 6 and the wafer guide after the wafer holder 6 is swung while the wafer W is held by the wafer guide 7. 7 is moved up and down relatively and returned to the wafer cradle 6 to rotate the wafer by changing the support portion of the wafer W on the wafer cradle 6.
[Selection] Figure 1

Description

  The present invention relates to a wafer rotating apparatus and a wafer rotating method for rotating a wafer immersed in a wafer processing tank such as a wafer cleaning apparatus or an etching processing apparatus in the processing tank.

  Conventionally, a cleaning process technique in a semiconductor manufacturing process is an indispensable process technique for maintaining the cleanliness of a wafer. In recent years, semiconductor manufacturing processes have been required to have higher accuracy, and the required particle removal performance has become increasingly severe.

  The ultrasonic cleaning method is widely used as one of such cleaning process techniques. The ultrasonic cleaning method is an important technique for improving the cleaning efficiency by removing the contaminants by irradiating the contaminants on the wafer surface with ultrasonic waves and using them together with a chemical cleaning method such as acid or alkali.

  In the ultrasonic cleaning apparatus, a portion that is a shadow of the member that supports the wafer in the traveling direction of the oscillated ultrasonic wave has a portion where the support member becomes an obstacle and the ultrasonic wave does not reach, or the ultrasonic generator Due to the difference in the degree of cleaning due to the difference in distance from the wafer, there is a problem in that cleaning unevenness occurs and uniform contaminant removal performance within the wafer surface cannot be obtained.

  In order to solve this problem, for example, in Patent Document 1 (Japanese Patent Laid-Open No. 2006-324495) and Patent Document 2 (Japanese Patent Laid-Open No. 2011-165694), a wafer cleaning apparatus that can suppress cleaning unevenness is disclosed. Proposed.

  The cleaning device of Patent Document 1 includes both a wafer guide and a wafer chuck in a cleaning tank, and changes the shadowed portion of the wafer support member by switching the holding of the wafer during cleaning of the wafer. It is intended to eliminate cleaning unevenness.

  Moreover, the cleaning apparatus of Patent Document 2 eliminates the unirradiated areas of the ultrasonic waves as a whole of the plurality of cleaning tanks by changing the positions of the receiving grooves that support the wafers in the plurality of cleaning tanks. That's what it meant.

JP 2006-324495 A JP 2011-165694 A

  However, in the apparatus of Patent Document 1, the non-irradiated area itself can be eliminated by changing the member that supports the wafer, but it is difficult to eliminate unevenness in cleaning quality for each part of the wafer. In particular, in recent years, as the diameter of wafers has been increased, the distance from the ultrasonic generator and the temperature and concentration of the cleaning liquid in the tank are not uniform, which has led to the problem that quality differences in cleaning occur. Yes.

  In addition, the semiconductor cleaning process is aimed at removing minute impurities, and the use of a complicated mechanism that generates minute debris such as belts and gears in the cleaning tank has severe particle removal conditions. Then it is virtually impossible.

  Further, the apparatus of Patent Document 2 is premised on the presence of a plurality of cleaning tanks, and there is a problem in that cleaning unevenness cannot be eliminated with a single cleaning tank.

  Therefore, the technical problem to be solved by the present invention is to eliminate the processing unevenness due to the failure of the wafer support member, the difference in the ultrasonic irradiation distance, the non-uniform distribution of the processing liquid, etc. It is an object of the present invention to provide a wafer rotating apparatus capable of rotating a wafer in a processing tank.

  In order to solve the above technical problem, the present invention provides a wafer rotating apparatus having the following configuration.

According to the first aspect of the present invention,
A processing liquid tank for storing the processing liquid and capable of immersing the wafer in the processing liquid;
A wafer cradle configured to hold a lower peripheral middle portion of the wafer in the processing liquid tank and swingable in a direction along the surface of the wafer;
It is arranged so as to sandwich the wafer cradle in the processing liquid tank, and moves in the vertical direction relative to the wafer cradle so that it is closer to the end than the holding portion by the wafer cradle at the lower peripheral edge of the wafer comprising of a set of wafer guide is configured to be able to hold the part, and
The wafer guide is positioned so as to be close to the periphery of the wafer when the wafer cradle swings in the first direction, and the wafer cradle is held in a state where the wafer is held by the wafer guide . by the returning in the wafer receiving base and the wafer guide and relatively moved in the vertical direction the wafer pedestal after swinging direction, the varied supporting portion of the wafer in the wafer receiving base wafer The present invention provides a wafer rotating apparatus characterized by rotating the wafer.

  According to a second aspect of the present invention, the wafer guide is configured to be movable up and down, and when the wafer guide is lowered, the wafer is returned to the wafer cradle. A wafer rotating apparatus is provided.

  According to a third aspect of the present invention, the wafer cradle is configured to swing around the center axis of the wafer to be supported as a rotation center. The wafer according to the first or second aspect, A rotating device is provided.

  According to a fourth aspect of the present invention, each of the wafer guides includes two guide bodies disposed in the thickness direction of the wafer, and a support disposed so as to be suspended between the two guide bodies. A wafer rotating apparatus according to any one of the first to third aspects is provided.

According to the fifth aspect of the present invention, the processing liquid is accommodated and the lower peripheral edge middle portion of the wafer is held in the processing liquid tank capable of immersing the wafer in the processing liquid, and is along the surface of the wafer. A wafer cradle configured to be swingable in a direction, and a portion closer to the end than the holding portion by the wafer cradle at the lower peripheral edge of the wafer by moving in a vertical direction relative to the wafer cradle Using a wafer rotation device comprising a set of wafer guides configured to be capable of holding
By swinging the wafer pedestal while the wafer is held by the wafer guide and then moving the wafer pedestal and the wafer guide relatively up and down to return to the wafer pedestal, There is provided a wafer rotating method, wherein the wafer is rotated by changing a wafer support portion in the wafer cradle.

  According to the sixth aspect of the present invention, in the transfer of the wafer between the wafer cradle and the wafer guide, the wafer guide is lifted so that the wafer is held from the wafer cradle to the wafer guide, A wafer rotation method according to a fifth aspect is provided, wherein the wafer is returned to the wafer cradle by lowering the wafer guide.

  According to the present invention, the wafer pedestal can be swung and the vertical position relative to the wafer guide can be changed, so that the wafer can be delivered to the wafer pedestal and the wafer guide. it can. Further, by changing the tilt angle of the wafer pedestal while the wafer guide is supporting the wafer, the wafer can be held in the circumferentially rotated state, so that the unevenness of the part due to the vertical position of the wafer can be maintained. Can be eliminated.

  In addition, the wafer pedestal is configured to swing around the center axis of the wafer to be supported, so that the wafer can be transferred without causing a positional shift or the like.

It is a schematic diagram which shows the structure of the wafer cleaning apparatus using the wafer rotating apparatus concerning embodiment of this invention. It is a partial cross section perspective view which shows typically the internal structure of the wafer rotating apparatus of FIG. It is a figure which shows each process of the operation | movement procedure of the wafer rotating apparatus of FIG. FIG. 4 is a diagram showing each of the subsequent steps shown in FIG. 3 of the operation procedure of the wafer rotating apparatus in FIG. 1.

  Hereinafter, a wafer rotating apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram showing a configuration of a wafer cleaning apparatus using a wafer rotating apparatus according to an embodiment of the present invention. FIG. 2 is a partial cross-sectional perspective view schematically showing the internal configuration of the wafer rotating apparatus of FIG. 1, and the propagation water tank 4 is omitted.

  A wafer cleaning apparatus 100 using the wafer rotating apparatus 1 according to the present embodiment includes a cleaning tank (inner tank) 2 that stores a cleaning liquid, and includes an outer tank 3 outside the cleaning tank 2. The cleaning liquid in the cleaning tank 2 overflows and flows into the outer tank 3, and a propagation water tank 4 filled with propagation water is provided outside the outer tank 3. An ultrasonic transmission unit 5 is provided on the outer surface of the bottom wall of the water tank 4.

  As shown in FIG. 2, the wafers W to be cleaned are arranged in the cleaning tank 2 so that a plurality of wafers W are parallel to each other at a predetermined interval. The wafer W is held by the wafer cradle 6.

As shown in FIG. 2, the wafer cradle 6 includes a pair of cradle main body portions 11 arranged substantially parallel to the wafer and a receiving member 12 provided on the lower end side of the cradle main body portion 11. A total of three receiving members 12 are provided, one at the central portion of the wafer and two within a range of a central angle of about 10 to 45 ° from the central portion, and the lower central portion at the periphery of the wafer at three points. The wafer W is held by supporting.

The main body 11 covers the central portion of the wafer W, and has a shape such that both end sides of the wafer are exposed to the outside. Further, the main body 11 is provided outside the cleaning tank 2 by a connecting leg 13 extending upward, and downward. Removably connected to the extending swing leg 14. When the wafer is put into the cleaning tank 2, the wafer holder 6 holds the wafer and is immersed in the tank from the upper side of the cleaning tank 2 to connect the connecting leg 13 and the swing leg 14.

  The swing leg 14 is supported by the outer surface of the propagation water tank 4 and is rotated along the main surface of the wafer W by the swing device 15 that rotates relative to the fixed shaft, as indicated by an arrow 90 in FIG. Swing in the direction. The swing center C of the swing leg 14 is preferably configured to be positioned on the center axis of the wafer W when connected to the wafer cradle 6.

  A pair of wafer guides 7 are provided on both sides of the wafer cradle 6. The wafer guide 7 is provided so as to be vertically movable as indicated by an arrow 91 by an elevating device 16 provided outside the cleaning tank 2. In the present embodiment, the lifting device is constituted by a cylinder, and the wafer cradle 6 is detachably fixed to a connecting portion 16b provided at the tip of the cylinder rod 16a.

  The elevation position 16 of the wafer guide 7 may be configured to be able to stop at an arbitrary position, or may be configured to be able to move between a plurality of predetermined positions such as an upper stage, a middle stage, and a lower stage. Good.

The wafer guide 7 includes a pair of guide main body portions 17 arranged side by side in the thickness direction of the wafer W, and a support member 18 disposed so as to be suspended between the two guide main body portions 17. The support member 18 is provided at a position where the lower left and right ends of the periphery of the wafer can be held. When the wafer guide 7 is raised by the lifting device 16 , the lower ends of the periphery of the wafer W are locked to the support member 18. Then, the wafer W is held by the wafer guide 7, and the wafer cradle 6 is in a state of not holding the wafer W.

  In this state, the wafer cradle 6 is swung so as to be inclined, and the wafer guide 7 is lowered to move the wafer W to the wafer cradle 6. Can be made. The drive control of the wafer cradle 6 and the wafer guide 7 can be automatically performed by controlling the operations of the swing device 15 and the lifting device 16 by a drive control means (not shown).

  Therefore, there is no region where the ultrasonic waves are not irradiated, and the wafer W is rotated, so that the vertical position is switched. Therefore, it is possible to solve the problem that the cleaning quality difference is caused by the distance from the ultrasonic generator 5 and the temperature and concentration distribution of the cleaning liquid in the tank.

  In the present embodiment, the drive parts of the wafer cradle 6 and the wafer guide 7 are both provided outside the cleaning tank 2, and there is no possibility of generating fine dust from the drive parts.

  Next, the operation of the wafer rotating apparatus according to the present embodiment will be described. In the following description, a mechanism for rotating the wafer will be mainly described.

  3 and 4 are diagrams showing each step of the operation procedure of the wafer rotating apparatus according to the present embodiment. In FIGS. 3 and 4, an arrow is attached to the same part of the wafer W to display the state of rotation of the wafer in an easy-to-understand manner.

  FIG. 3A shows a process of putting the wafer held on the wafer cradle 6 into the cleaning tank 2. As shown in FIG. 3A, when the wafer is loaded, the wafer guide 7 is positioned at the lower stage, and as shown by an arrow 92, the holder cradle 6 is lowered into the cleaning tank 2 by a transfer robot (not shown). And put it in. In a state where the wafer guide 7 is positioned at the lower stage, the support member 18 of the wafer guide 7 does not contact the wafer W and holds the wafer W only by the holder cradle 6. When the wafer W is cleaned in the cleaning tank 2 in this state, the ultrasonic wave does not reach the portion where the receiving member 12 of the holder receiving base 6 is located, and cleaning unevenness occurs. The holding part of the wafer W is changed.

  In the state shown in FIG. 3B, the wafer guide 7 is raised to the middle as shown by an arrow 93 while the wafer cradle 6 is maintained neutral. In this state, the support members 18 of the wafer guide 7 are in close proximity to the left and right sides of the wafer W, but the wafer W is still held on the wafer cradle 6.

  Next, as shown in FIG. 3C, the wafer cradle 6 is tilted as indicated by an arrow 94. In the present embodiment, the inclination angle is approximately 15 °. In this state, since the wafer W is held on the wafer holder 6 as described above, the wafer W is inclined according to the inclination of the wafer holder 6. In addition, since the support member 18 of the wafer guide 7 is close to the left and right ends of the wafer W, the wafer W is prevented from falling by the tilting operation of the wafer cradle 6.

  Next, in FIG. 3D, the wafer guide 7 is raised to the upper stage as indicated by an arrow 95, and the wafer W is brought into a state of floating from the wafer cradle 6. In this state, the wafer W is held only by the wafer guide 7, and the guide cradle 6 can freely rotate.

  As shown by an arrow 96 in FIG. 4E, the wafer cradle 6 is inclined approximately 15 ° in the reverse direction. In this state, since the wafer W is held by the wafer guide 7 as described above, the inclination of the wafer receiving base 6 does not affect the inclination of the wafer W. As a result, the contact between the wafer W and the wafer cradle 6 can be shifted by 30 °.

  Next, as indicated by an arrow 97 in FIG. 4 (f), the wafer guide 7 is lowered to the middle stage, and the wafer W is placed on the wafer cradle 6. As shown in FIG. 4G, the wafer cradle 6 is inclined approximately 15 ° as indicated by an arrow 98. In this state, since the wafer W is held on the wafer pedestal 6 as described above, the wafer W is tilted according to the tilt of the wafer pedestal 6 and rotated by 30 °. In addition, since the support member 18 of the wafer guide 7 is close to the left and right ends of the wafer W, the wafer W is prevented from falling by the tilting operation of the wafer cradle 6.

  Next, in FIG. 4 (h), the wafer guide 7 is raised to the upper stage as indicated by an arrow 99 to bring the wafer W into a state of being lifted from the wafer cradle 6. In this state, the wafer W is held only by the wafer guide 7, and the guide cradle 6 can freely rotate.

  Thereafter, by repeating the operations from FIG. 4E to FIG. 4H, the wafer W can be rotated by 30 °.

As described above, according to the wafer cleaning apparatus according to the embodiment of the present invention, there is no region that is not irradiated with ultrasonic waves, and the wafer W is rotated so that the vertical position is switched. Therefore, it is possible to solve the problem that the cleaning quality difference is caused by the distance from the ultrasonic generator 5 and the temperature and concentration distribution of the cleaning liquid in the tank.
be able to

  Further, since neither the drive mechanism of the wafer cradle 6 nor the wafer guide 7 exists in the cleaning tank 2, fine dust is not generated by the operation of these drive members, and the cleaning liquid is not contaminated.

  In addition, this invention is not limited to the said embodiment, It can implement in another various aspect. For example, although the present embodiment has been described with reference to a wafer cleaning apparatus, it can also be used in an etching processing apparatus.

  Further, the mode of rotation of the wafer W is not limited to the process shown in FIGS. 3 and 4, and the wafer W is transferred between the wafer guide 7 and the wafer cradle 6 and held by the wafer guide 7. By varying the inclination angle of the wafer cradle 6 at the timing, the contact procedure between the wafer W and the wafer cradle 6 is made different, and as a result, the operation procedure for rotating the wafer W is widely included.

DESCRIPTION OF SYMBOLS 1 Wafer rotation apparatus 2 Cleaning tank 3 Outer tank 4 Propagation water tank 5 Ultrasonic transmission part 6 Wafer receiving base 7 Wafer guide 11 Receiving body part 12 Receiving member 13 Connecting leg 14 Swing leg 15 Swing apparatus 16 Lifting apparatus 17 Guide Main body 18 Support member 100 Wafer cleaning device C Center of rotation W Wafer

Claims (6)

A processing liquid tank for storing the processing liquid and capable of immersing the wafer in the processing liquid;
A wafer cradle configured to hold a lower peripheral middle portion of the wafer in the processing liquid tank and swingable in a direction along the surface of the wafer;
It is arranged so as to sandwich the wafer cradle in the processing liquid tank, and moves in the vertical direction relative to the wafer cradle so that it is closer to the end than the holding portion by the wafer cradle at the lower peripheral edge of the wafer comprising of a set of wafer guide is configured to be able to hold the part, and
The wafer guide is positioned so as to be close to the periphery of the wafer when the wafer cradle swings in the first direction, and the wafer cradle is held in a state where the wafer is held by the wafer guide . by the returning in the wafer receiving base and the wafer guide and relatively moved in the vertical direction the wafer pedestal after swinging direction, the varied supporting portion of the wafer in the wafer receiving base wafer A wafer rotating device characterized by rotating the wafer.   The wafer rotation apparatus according to claim 1, wherein the wafer guide is configured to be movable up and down, and the wafer returns to the wafer receiving base when the wafer guide is lowered.   The wafer rotating apparatus according to claim 1, wherein the wafer cradle is configured to swing around a center axis of the wafer to be supported.   Each of the wafer guides includes two guide bodies disposed in the thickness direction of the wafer, and a support member disposed to be suspended between the two guide bodies. The wafer rotating apparatus according to claim 1. It is configured to hold the processing liquid, hold the lower peripheral middle portion of the wafer in a processing liquid tank in which the wafer can be immersed in the processing liquid, and can swing in the direction along the surface of the wafer. One set configured to hold a wafer cradle and a portion on the end side of the wafer cradle at a lower end of the periphery of the wafer than the holding portion by the wafer cradle by moving in a vertical direction relative to the wafer cradle. Using a wafer rotation device comprising:
By swinging the wafer pedestal while the wafer is held by the wafer guide and then moving the wafer pedestal and the wafer guide relatively up and down to return to the wafer pedestal, A method of rotating a wafer, wherein the wafer is rotated with different supporting portions of the wafer in the wafer cradle. The wafer is transferred between the wafer cradle and the wafer guide by lifting the wafer guide so that the wafer is held from the wafer cradle to the wafer guide, and by lowering the wafer guide. 6. The wafer rotation method according to claim 5, wherein the wafer returns to the stage.

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