Abstract:
A semiconductor device manufacturing apparatus includes a first supporting unit; a first brush configured to brush and clean a substrate fixed to the first supporting unit; a second supporting unit; and a second brush configured to brush and clean the substrate fixed to the second supporting unit. The first supporting unit rotates in a state that the wafer is fixed to the first supporting unit. The second supporting unit comprises a roller configured to contact a peripheral portion of the wafer and to rotate the wafer, and the first supporting unit and the second supporting unit approach to and separate from each other.

Description:
BACKGROUND OF THE INVENTION  
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a semiconductor manufacturing apparatus and a method of manufacturing a semiconductor device, and especially relates to a semiconductor manufacturing apparatus for a wafer cleaning process and a method of manufacturing a semiconductor device through a wafer cleaning process. This patent application is based on Japanese patent application No. 2007-029787. The disclosure thereof is incorporated herein by reference. 
         [0003]    2. Description of Related Art 
         [0004]    A wafer is cleaned to remove particles attaching to the wafer and contaminants such as organic substances or metallic impurities, every time processing is completed in respective steps of a semiconductor manufacturing process. 
         [0005]    Japanese Patent Application Publication (JP-P2003-007662A, first conventional example) discloses a substrate cleaning apparatus. The substrate cleaning apparatus includes an upper cleaning unit and a lower cleaning unit which are laid in a double-decker shape; and a conveying robot for conveying a substrate between both of the cleaning units. The upper cleaning unit includes a first substrate supporting mechanism for supporting the substrate; an upper roll sponge for cleaning an upper surface of the substrate; and a lower roll sponge for cleaning a lower surface of the substrate. The first substrate supporting mechanism includes a plurality of chuck rollers, which are arranged on a periphery of the substrate at even intervals. The chuck rollers move in a direction of a radius of the substrate and hold the substrate between them. The substrate is rotated through rotation of the chuck rollers. The lower cleaning unit includes a second substrate supporting mechanism for supporting the substrate and a pencil-type pencil sponge for cleaning the upper surface of the substrate. The second substrate supporting mechanism includes a wafer chuck wheel having a plurality of clicks on the periphery of the wafer. A plurality of the clicks sandwiches the peripheral part on the substrate. The wafer chuck wheel is rotated by a motor. The conveying robot is provided in adjacent to the both cleaning units. The conveying robot can carry the substrate in and out of the upper cleaning unit and the lower cleaning unit and move the substrate in the horizontal direction, and can move the substrate upward and downward. 
         [0006]    Cleaning of the substrate by the above mentioned substrate cleaning apparatus will be described. The conveying robot carries the substrate received from a unit for a previous step into the upper cleaning unit and transfers the substrate to the first substrate supporting mechanism. The upper cleaning unit cleans the upper surface and lower surface of the substrate while rotating the substrate by the chuck rollers. After the cleaning is completed, the conveying robot receives the substrate from the first substrate supporting mechanism, carries the substrate out of the upper cleaning unit, and lowers the substrate to the height of the lower cleaning unit. The conveying robot carries the substrate to the lower cleaning unit and transfers the substrate to the second substrate supporting mechanism. The lower cleaning unit cleans the substrate by making the pencil sponge contact to the upper surface while rotating the substrate at a low speed by using the wafer chuck wheel. After the cleaning is completed, the lower cleaning unit removes cleaning fluid attached to the substrate by using centrifugal force through rotation of the wafer chuck wheel at high speed to dry the substrate. After the drying is completed, the conveying robot receives the substrate from the second substrate supporting mechanism, carries the substrate out of the lower cleaning unit, and stores the substrate in a cassette. 
         [0007]    In the above-described substrate cleaning apparatus, an installation area of the whole of the substrate cleaning apparatus including the conveying robot is large, since the conveying robot is provided in adjacent to both the cleaning units. In addition, since the substrate is carried in the lower cleaning unit after carried out of the upper cleaning unit once, it seems more likely that the substrate is contaminated and it takes long time to convey the substrate. Furthermore, since a multi-jointed robot having a plurality of joint parts is used, the movable parts of the conveying robot are likely to fail. 
       SUMMARY  
       [0008]    In an aspect of the present invention, a semiconductor device manufacturing apparatus includes a first supporting unit; a first brush configured to brush and clean a substrate fixed to the first supporting unit; a second supporting unit; and a second brush configured to brush and clean the substrate fixed to the second supporting unit. The first supporting unit rotates in a state that the wafer is fixed to the first supporting unit. The second supporting unit comprises a roller configured to contact a peripheral portion of the wafer and to rotate the wafer, and the first supporting unit and the second supporting unit approach to and separate from each other. 
         [0009]    In another aspect of the present invention, there is provided a method of manufacturing a semiconductor device by a manufacturing apparatus which comprises: a first supporting unit configured to rotate in a state that a substrate is fixed; and a second supporting unit comprising a roller configured to contact a peripheral portion of the wafer and to rotate the wafer. The method includes brushing and cleaning the wafer supported by the second supporting unit; making the first supporting unit and the second supporting unit approach; and transferring the wafer from the second supporting unit to the first supporting unit. 
         [0010]    According to the present invention, a semiconductor device manufacturing apparatus and a method of manufacturing a semiconductor device are provided which can pass a wafer directly from one supporting unit for rotating the wafer to another supporting unit for rotating the wafer. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0011]    The above and other objects, advantages and features of the present invention will be more apparent from the following description of embodiments taken in conjunction with the accompanying drawings, in which: 
           [0012]      FIG. 1  is a side view showing a semiconductor manufacturing apparatus according to a first embodiment of the present invention; 
           [0013]      FIG. 2  is a side view showing an operation in passing a wafer in the semiconductor manufacturing apparatus according to the first embodiment; 
           [0014]      FIG. 3  is an upper view showing a first supporting apparatus and a second supporting apparatus of the semiconductor manufacturing apparatus according to the first embodiment; 
           [0015]      FIG. 4  is an upper view showing an operation in passing a wafer in the first supporting apparatus and the second supporting apparatus; 
           [0016]      FIG. 5  is an upper view showing a first supporting apparatus and an upper brush of the semiconductor manufacturing apparatus according to a second embodiment of the present invention; and 
           [0017]      FIG. 6  is a side view showing an operation in passing a wafer of a lower brush in the semiconductor manufacturing apparatus according to the second embodiment. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0018]    Hereinafter, a semiconductor manufacturing apparatus and a method for manufacturing a semiconductor device according to embodiments of the present invention will be described with reference to the attached drawings. In the drawings, directions of X, Y, and Z are shown which are perpendicular to each other The Z direction, for example, is a vertical direction. The X and Y directions, for example, are horizontal directions which are perpendicular to each other. 
       First Embodiment  
       [0019]      FIG. 1  is a side view of a semiconductor manufacturing apparatus  1  according to a first embodiment of the present invention. The semiconductor manufacturing apparatus  1  includes a chamber  2 , a shutter  3 , a substrate supporting unit  4  for cleaning both surfaces of a substrate (a semiconductor wafer), an upper brush  8 , a lower brush  11 , nozzles  14  to  17 , a substrate supporting unit  18  for cleaning one surface of the wafer, a brush  24 , and a cover  27 . 
         [0020]    The shutter  3  is provided to divide the chamber  2  into an upper side  2   a  and a lower side  2   b , and can be opened and closed. The upper side  2   a  is arranged on an upper side of the Z direction and the lower side  2   b  is arranged on a lower side of the Z direction. After cleaning both surfaces of the wafer  30  received from a previous stage in the upper side  2   a , the semiconductor manufacturing apparatus  1  cleans one surface of the wafer  30  in the lower side  2   b , dries the wafer  30 , and transfers the wafer to a next stage. 
         [0021]    The substrate supporting unit  4 , the upper brush  8 , the lower brush  11 , and the nozzles  14  and  15  are arranged on the upper side  2   a . The substrate supporting unit  4  includes a plurality of rollers  7 . The plurality of rollers  7  supports the wafer  30  by contacting a peripheral portion of the wafer  30 . The wafer  30  has a shape of a circular disk and includes a front surface  30   a  and a rear surface  30   b  on both sides as surfaces of the circular disk. Each of the plurality of rollers  7  can rotate around a rotation axis parallel with the Z direction. When at least one of the plurality of rollers  7  is rotated by a driving unit (not shown), the wafer  30  rotates around the rotation axis which passes a center of the wafer  30  and is parallel with the Z direction. The substrate supporting unit  4  is also called a roller chuck. Here, the front surface  30   a  faces upward and the rear surface  30   b  faces the lower substrate supporting unit  18 . A scrub cleaning is performed on the front surface  30   a  by the upper brush  8  while spraying cleaning fluid to the surface  30   a  from the nozzle  14  and rotating the wafer  30  by the roller  7 . The upper brush  8  includes a body of brush  9 , and an arm  10  for supporting the brush body  9  rotatably around a brush rotation axis parallel with the Z direction. In the brush body  9 , hairs are transplanted on a surface of the circular disk perpendicular to the rotation axis of the brush. The scrub cleaning is performed on the rear surface  30   b  by the lower brush  11  while spraying cleaning fluid to the rear surface  30   b  from the nozzle  15  and rotating the wafer  30  by the roller  7 . The lower brush  11  includes a brush body  12 , and an arm  13  for supporting the brush body  12  rotatably around the brush rotation axis parallel with the Z direction. In the brush body  12 , hairs are transplanted on a surface of the circular disk perpendicular to the rotation axis of the brush. 
         [0022]    The nozzle  16 , the nozzle  17 , the substrate supporting unit  18 , the brush  24  and the cover  27  are arranged on the lower side  2   b . The substrate supporting unit  18  can rotate around a rotation axis of the supporting unit parallel with the Z direction in a state that the wafer  30  is fixed so that the surface  30   a  faces upward. The substrate supporting unit  18  is also called a mechanical chuck. This rotation axis of the supporting unit passes a center of the wafer  30 . This rotation axis of the supporting unit and the rotation axis of the wafer  30  when the wafer  30  is rotated by the rollers  7  are arranged on a same line. The scrub cleaning is performed on the front surface  30   a  by the brush  24  while spraying cleaning fluid to the rear surface  30   a  from the nozzle  16  and to the rear surface  30   b  from the nozzle  17 , and rotating the substrate supporting unit  18  at a relatively low speed. The brush  24  includes a pencil type brush body  25 , an arm  26  for supporting the brush body  25  rotatably around the rotation axis of the brush parallel with the Z direction. The brush  24  is also called a pencil brush. The cover  27  covers circumference of the substrate supporting unit  18  when the wafer  30  is cleaned by using the brush  24 . After the cleaning is completed, cleaning fluid attached to the wafer  30  is removed by centrifugal force while rotating the substrate supporting unit  18  at a relatively high speed to dry the wafer  30 . 
         [0023]    Referring to  FIGS. 2 to 4 , an operation of the semiconductor manufacturing apparatus  1  when the wafer  30  whose both surfaces have been cleaned in the upper side  2   a  is transferred from the substrate supporting unit  4  to the substrate supporting unit  18 . 
         [0024]    Referring to  FIG. 2 , as shown by an arrow  40 , the brush  24  is first evacuated from a space between the wafer  30  supported by the substrate supporting unit  4  and the substrate supporting unit  18  along the Y direction. Subsequently, as shown by an arrow  41 , the lower brush  11  is evacuated from a space between the wafer  30  supported by the substrate supporting unit  4  and the substrate supporting unit  18  along the Y direction. Subsequently, as shown by an arrow  42 , the upper side  2   a  and the lower side  2   b  are connected by opening the shutter  3 . Subsequently, as shown by an arrow  43 , the substrate supporting unit  18  is made to approximate the substrate supporting unit  4  along the Z direction. 
         [0025]      FIG. 3  is an upper view of the substrate supporting unit  4  and the substrate supporting unit  18  when the substrate supporting unit  18  approximates the substrate supporting unit  4 . The substrate supporting unit  4  includes a roller pedestal  5  and a roller pedestal  6 . To each of the roller pedestal  5  and the roller pedestal  6 , the plurality of rollers  7  are attached to rotate around the rotation axis of the roller parallel with the Z direction. The substrate supporting unit  4  supports the wafer  30  in a condition that the plurality of rollers  7  provided by the roller pedestal  5  and the roller pedestal  6  contact the peripheral portions of the wafer  30 . The roller pedestal  5  and the roller pedestal  6  can be approximated and separated from each other along the X direction. Meanwhile, the substrate supporting unit  18  includes a rotation body  19 , a rotation body  20 , a plurality of fixed supporters  21 , a plurality of movable supporters  22 , and links  23 . The rotation body  19  can rotate around the rotation axis of the supporting unit parallel with the Z direction. The rotation body  20  is supported by the rotation body  19  to rotate around the rotation axis of the supporting unit against the rotation body  19 . Each of the plurality of fixed supporters  21  is fixed to the rotation body  19 . Each of the plurality of movable supporters  22  is supported by the rotation body  19  to rotate around the rotation axis of the movable supporter parallel with the rotation axis of the supporting unit against the rotation body  19 , and includes a contacting part  22   a  provided on a position which is not aligned with the rotation axis of the movable supporter. Each of the links  23  is provided for one of the plurality of movable supporters  22 , and connects each of the plurality of movable supporters  22  with the rotation body  20 . The contacting part  22   a  is arranged on a circumference made by employing the rotation axis of the supporting unit as a central axis. The link  23  rotates each of the plurality of movable supporters  22  against the rotation body  19  so that a radius of the circumference on which the contacting part  22   a  is arranged can be reduced and increased in accordance with forward and reverse rotations of the rotation body  20  against the rotation body  19 . 
         [0026]    Referring to  FIG. 4 , as shown by an arrow  44 , the wafer  30  is released from the substrate supporting unit  4  by separating the roller pedestal  5  and the roller pedestal  6  along the X direction. The released wafer  30  is supported by the plurality of fixed supporters  21 . Subsequently, the rotation body  20  rotates against the rotation body  19 , the contacting part  22   a  contacts the peripheral part of the wafer  30  by reducing the radius of the circumference on which the contacting part  22   a  is arranged, and the wafer  30  is fixed to the substrate supporting unit  18 . 
         [0027]    Referring to  FIG. 2 , as shown by an arrow  45 , the substrate supporting unit  18  to which the wafer  30  is fixed is separated from the substrate supporting unit  4  along the Z direction and arranged on the lower side  2   b . Subsequently, as shown by an arrow  46 , the upper side  2   a  and the lower side  2   b  are isolated by closing the shutter  3 . After that, the wafer  30  is cleaned with using the brush  24 . 
         [0028]    In the present embodiment, since the wafer  30  is transferred directly from the substrate supporting unit  4  to the substrate supporting unit  18 , a required time for transferring the wafer can be short. In addition, a robot for conveying the wafer  30  from the substrate supporting unit  4  to the substrate supporting unit  18  is riot be required. For this reason, an installation space for the conveying robot is not required. In addition, the wafer  30  can be prevented from being contaminated since the wafer  30  is not carried out of the chamber  2  when the wafer  30  is transferred. 
         [0029]    In the present embodiment, the semiconductor manufacturing apparatus  1  can be realized in a simple structure since the substrate supporting unit  4  and the substrate supporting unit  18  are approximated and separated by moving the substrate supporting unit  18 . Although the structure is complicated slightly, the substrate supporting unit  4  and the substrate supporting unit  18  may be approximated and separated by moving the substrate supporting unit  4 . Even in this case, the wafer  30  is transferred directly from the substrate supporting unit  4  to the substrate supporting unit  18 . Furthermore, in the present embodiment, the rotating movement of the rotation body  20  for fixing and releasing the wafer  30  by the substrate supporting unit  18  against the rotation body  19  and the rotating movement of the whole of the substrate supporting unit  18  for cleaning and drying the wafer  30  are performed around a common rotation axis of the supporting unit, and the substrate supporting unit  18  is moved along this rotation axis of the supporting unit. For this reason, the substrate supporting unit  18  can be manufactured easily. 
         [0030]    In the present embodiment, the substrate supporting unit  4  can be realized in a simple structure since the wafer  30  is supported and released by approximating and separating the roller pedestal  5  and the roller pedestal  6  to which the plurality of rollers  7  is attached. Although the structure of the substrate supporting unit  4  is complicated slightly, the wafer  30  may be supported and released by moving each of the plurality of rollers  7  in the radius direction of the wafer  30 . 
         [0031]    In the present embodiment, during the cleaning of one wafer  30  in the lower side  2   b , another wafer  30  can be cleaned in the upper side  2   a  since the chamber  2  is divided by closing the shutter  3 . 
       Second Embodiment  
       [0032]    The semiconductor manufacturing apparatus  1 ′ according to a second embodiment of the present invention will be described below. Similar to the semiconductor manufacturing apparatus  1 , the semiconductor manufacturing apparatus  1 ′ includes the chamber  2 , the shutter  3 , the substrate supporting unit  4 , the nozzles  14  to  17 , the substrate supporting unit  18 , the brush  24 , and the cover  27 . These configurations and operations are same as those of the semiconductor manufacturing apparatus  1 . 
         [0033]    As shown in  FIG. 5 , the semiconductor manufacturing apparatus  1 ′ includes an upper brush  8 ′ instead of the upper brush  8 . The upper brush  8 ′ is used for performing the scrub cleaning for the front surface  30   a  of the wafer  30  supported by the substrate supporting unit  4 . The upper brush  8 ′ includes a brush body  9 ′, and an arm  10 ′ for supporting the brush body  9 ′ rotatably around the rotation axis of the brush parallel with the X direction. In the brush body  9 ′, hairs are transplanted on a surface of a circular disk perpendicular to the rotation axis of the brush. 
         [0034]    As shown in  FIG. 6 , the semiconductor manufacturing apparatus  1 ′ includes a lower brush  11 ′ instead of the lower brush  11 . The lower brush  11 ′ is used for performing the scrub cleaning for the rear surface  30   b  of the wafer  30  supported by the substrate supporting unit  4 . The lower brush  11 ′ includes a brush body  12 ′, and an arm  13 ′ for supporting the brush body  12 ′ rotatably around the rotation axis of the brush parallel with the X direction. In the brush body  12 ′, hairs are transplanted on a surface of a circular disk perpendicular to the rotation axis of the brush The arm  13 ′ is supported against the chamber  2  to oscillate around an oscillating axis parallel with the X direction. In the semiconductor manufacturing apparatus  1 ′, when the wafer  30  is transferred from the substrate supporting unit  4  to the substrate supporting unit  18 , the lower brush  11 ′ is evacuated from a space between the wafer  30  supported by the substrate supporting unit  4  and the substrate supporting unit  18  by oscillating the lower brush  11 ′ from a cleaning position shown by a broken line to an evacuating position shown by a solid line in  FIG. 6 . 
         [0035]    In the present embodiment, an installation area of the semiconductor manufacturing apparatus  1 ′ can be made small since the lower brush  11 ′ is evacuated by being oscillated around the horizontal oscillating axis without being evacuated along the horizontal direction. 
         [0036]    Although the present invention has been described above in connection with several embodiments thereof, it will be appreciated by those skilled in the art that those embodiments are provided solely for illustrating the present invention, and should not be relied upon to construe the appended claims in a limiting sense.