Patent Publication Number: US-2016233115-A1

Title: Cleaning apparatus for semiconductor equipment

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a CIP application of U.S. application Ser. No. 14/018,928, filed on Sep. 5, 2013 and entitled Semiconductor Equipment, which in turn is a continuation application of U.S. application Ser. No. 13/856,092, filed on Apr. 3, 2013 and entitled Semiconductor Equipment, which in turn is a divisional application of U.S. application Ser. No. 12/726,183, filed on Mar. 17, 2010 and entitled Semiconductor Equipment, which in turn claims the priority benefit of Taiwan Patent Application No. 099102839, filed on Feb. 1, 2010. This application is also a CIP application of U.S. application Ser. No. 14/703,113, filed on May 4, 2015 and entitled Wafer Holder, which in turn claims the priority benefit of TW Application No. 104104677, filed on Feb. 12, 2015. The entire contents of all of the foregoing applications are herein expressly incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention generally relates to semiconductor equipment, and more particularly to a cleaning apparatus applied on a semiconductor equipment to have a machine-maneuvered cleaning function. 
     2. Description of Related Art 
     Semiconductor manufacturing equipment is commonly used in the production of semiconductor components. The semiconductor manufacturing equipment typically has a reaction chamber. The reaction gases required by the semiconductor manufacturing process can be provided into the reaction chamber by a showerhead of the reaction chamber. The residues, such as deposited material or contaminants, may be attached within the reaction chamber after several executions of semiconductor manufacturing processes. Thus, process results and the process yields are affected by the residues. 
     Generally speaking, the residues within the reaction chamber can be removed by specific reaction gases. On the other hand, the residues within the reaction chamber can be removed manually when the reaction chamber is opened. However, using specific reaction gases to remove the residues within the reaction chamber is usually ineffective. Removing the residues within the reaction chamber manually with the reaction chamber opened usually leads to long maintenance times, inconsistent process results, and so on. 
     For the reason mentioned above, there is a need to propose a cleaning apparatus that can be integrated into said semiconductor equipment to have machine-maneuvered cleaning function. The semiconductor equipment should be capable of driving the cleaning apparatus to remove the residues within the reaction chamber. 
     SUMMARY OF THE INVENTION 
     Accordingly, the present invention has been made in order to meet such a need as described above, it being an object of the present invention to provide semiconductor equipment a machine-maneuvered cleaning function. The semiconductor equipment is capable of removing residues within a reaction chamber with cleaning brushes. 
     In order to achieve the above object, the present invention provides a cleaning apparatus for semiconductor equipment. The semiconductor equipment includes a reaction chamber, a movable frame. The cleaning apparatus includes a cleaning pad with a plurality of brushes thereon. The brushes are disposed on the surface of the cleaning pad. The movable frame rotationally maneuvers the cleaning pad to remove the residues within the semiconductor equipment. 
     In one embodiment, the invention provides a method for cleaning a semiconductor equipment comprising the following steps first of all, a cleaning apparatus comprising a cleaning pad with a plurality of brushes on the cleaning pad is provided. Then the cleaning apparatus is placed on a movable frame of the semiconductor equipment. Finally, the cleaning apparatus and the movable frame are moved and rotated to remove residues within the semiconductor equipment by using the brushes against the residues, wherein the movable frame is configured to hold a susceptor for holding at least one wafer and the cleaning apparatus. 
     In another embodiment, the invention provides a semiconductor equipment with an in-situ cleaning function comprising a reaction chamber, a showerhead in the reaction chamber, a movable frame under the showerhead, a transmission device, and a cleaning apparatus comprising a cleaning pad with a plurality of brushes thereon. The transmission device is configured to linearly move and to rotate the movable frame. The movable frame is configured to hold a susceptor for holding at least one wafer and the cleaning apparatus, the cleaning apparatus is configured to be located on the movable frame to remove residues within the semiconductor equipment by using the brushes against the residues via moving and rotating the cleaning apparatus and the movable frame. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram illustrating a semiconductor equipment in accordance with a preferred embodiment of the present invention. 
         FIG. 2A  is a schematic diagram illustrating the susceptor  230  holding a plurality of wafers  201  being loaded on the movable frame  220  by the fork  242  in  FIG. 1  in accordance with an embodiment of the present invention. 
         FIG. 2B  is a front view illustrating the susceptor  230  holding the wafers  201  being loaded on the movable frame  220 . 
         FIG. 3A  is a schematic diagram illustrating a cleaning pad  234  being loaded on the movable frame  220  by the fork  242  in  FIG. 1  in accordance with an embodiment of the present invention. 
         FIG. 3B  is a front view illustrating the cleaning pad  234  being loaded on the movable frame  220 . 
         FIGS. 3C and 3D  are schematic diagrams illustrating the brushes  236  in accordance with one embodiment of the present invention. 
         FIGS. 4A and 4B  illustrate the cleaning pad  234  with the brushes  236  arranged to form triangle patterns in accordance with two embodiments of the present invention. 
         FIG. 5  depicts an in-situ cleaning operation via the cleaning pad  234  according to embodiments of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     A detailed description of the present invention will be provided in connection with the following embodiments, which are not intended to limit the scope of the present invention and which can be adapted for other applications. While the drawings are illustrated in detail, it is appreciated that the quantity of the disclosed components may be greater or less than that disclosed except for instances expressly restricting the amount of the components. 
       FIG. 1  is a schematic diagram illustrating semiconductor equipment  200  in accordance with a preferred embodiment of the present invention. The semiconductor equipment  200  includes a reaction chamber  210 , a movable frame  220 , and a robot arm  240  with a fork  242 . The reaction chamber  210  in turn includes a showerhead  215 . Hence, reaction gases required by the semiconductor manufacturing process can be provided into the reaction chamber  210  by way of the showerhead  215 . The showerhead  215  is disposed on an upper portion of the reaction chamber  210 . The movable frame  220  is disposed within the reaction chamber  210 . The movable frame  220  is capable of carrying a susceptor  230 . The susceptor  230  is capable of carrying at least one wafer. The movable frame  220  is able to make the susceptor  230  move vertically and/or rotate. The susceptor  230  comprises two stages  231  in the lower portion of the susceptor  230 . The susceptor  230  can be disposed on the movable frame  220  via any suitable configuration, such as notches (not shown) in the movable frame  220  and protrusions (not shown) in the susceptor  230 . 
     The semiconductor equipment  200  can further include a first frame  214 , a second frame  213 , a third frame  212 , a transmission device  290 , and a flexible catheter  281 . The transmission device  290  in turn includes a linear transmission device  291 . The linear transmission device  291  is disposed between the first frame  214  and the second frame  213 . Hence, by way of the linear transmission device  291 , the second frame  213  can move vertically relative to the first frame  214 . The movable frame  220  is disposed on the second frame  213 . When the second frame  213  moves vertically, the movable frame  220  also moves vertically. The flexible catheter  281  is disposed between the third frame  212  and the second frame  213 . The flexible catheter  281  is used to prevent the gases within the reaction chamber  210  from leaking to the outside of the reaction chamber  210 . The transmission device  290  includes a rotation transmission device. In this embodiment, the rotation transmission device includes a motor  292  and a gear assembly  293 . Power from the motor  292  is transmitted to the movable frame  220  by the gear assembly  293  so as to make the movable frame  220  rotate. 
     The susceptor  230  can be loaded on or removed from the movable frame  220  by the robot arm  240  with the fork  242 . In order to load and dispose the susceptor  230  on the movable frame  220 , the fork  242  drove by the robot arm  240  extends into the stages  231  of the susceptor  230  so as to lift up the susceptor  230 . Then the gate valve  211  is opened and the fork  242  carrying the susceptor  230  extends into the reaction chamber  210  to put the susceptor  230  on the movable frame  220 . To remove the susceptor  230  from the movable frame  220 , the fork  242  extends into the reaction chamber  210  after the gate valve  211  is opened. Then the fork  242  drove by the robot arm  240  extends into the stages  231  of the susceptor  230  so as to lift up the susceptor  230 . Next the fork  242  carrying the susceptor  230  retracts from the reaction chamber  210 . In order to load or remove the susceptor  230 , the movable frame  220  may need to be moved vertically and to rotate so as to allow the fork  242  extending into the stages  231  of the susceptor  230 . 
       FIG. 2A  is a schematic diagram illustrating the susceptor  230  holding a plurality of wafers  201  being loaded on the movable frame  220  by the fork  242  in  FIG. 1  in accordance with an embodiment of the present invention.  FIG. 2B  is a front view illustrating the susceptor  230  holding the wafers  201  being loaded on the movable frame  220 . As shown in  FIG. 2A , the susceptor  230  is disposed on the movable frame  220  and the wafers  201  are loaded on the susceptor  230 . The susceptor  230  can be loaded on or removed from the movable frame  220  by the fork  242 . During loading or removing the susceptor  230 , the fork  242  extends into the stages  231  of the susceptor  230  so as to lift up and move the susceptor  230 . 
     Please referring back to  FIG. 1 , during the deposition process, reaction gases are delivered via the showerhead  215  to initiate deposition onto the wafers  201 . However, possible residues also may be formed within the reaction chamber  210  during the deposition process. Particularly, residues resulting from various reasons such as non-uniform distribution of reacting gases or early reaction between reactants usually accumulate on the lower surface of the showerhead  215 . Such undesired deposition consumes reactants and decreases the efficiency as well as the yield ratio, and the non-uniform deposition would further reduce the throughput of the process. Frequent cleaning, as a result, is usually required for the reaction chamber  210  and the showerhead  215 . 
       FIG. 3A  is a schematic diagram illustrating a cleaning apparatus being loaded on the movable frame  220  by the fork  242  in  FIG. 1  in accordance with an embodiment of the present invention.  FIG. 3B  is a front view illustrating the cleaning apparatus being loaded on the movable frame  220 . The cleaning apparatus comprises a cleaning pad  234  with a plurality of brushes  236  thereon and two stages  235  in the lower portion of the cleaning pad  234 . The cleaning apparatus can be disposed on the movable frame  220  via any suitable configuration, such as notches (not shown) in the movable frame  220  and protrusions (not shown) in the cleaning pad  234  similar to that of the susceptor  230 . The material of the cleaning pad  234  comprises graphite and titanium, while the material of the brushes comprise stainless-steel and engineering plastics such as nylon. The cleaning pad  234  can be a graphite coated titanium pad. In one embodiment, the cleaning pad  234  has a shape of circular disk similar to the susceptor  230 . In this embodiment, the brushes  236  are arranged to form a cross pattern with four brushes. 
       FIGS. 3C and 3D  are schematic diagrams illustrating the brushes  236  in accordance with one embodiment of the present invention. The brushes  236  comprise a plurality of hairs disposed in slots of the cleaning pad  234 . The hairs of the brushes  236  are further supported by strips  237  with a L shape cross section. The strips  237  can be mounted on the cleaning pad  234  via any suitable devices, such as screw nuts  239 . In one embodiment, the brushes  236  are tilt brushes which can be achieved by the strips  237  with different L shape cross sections on two sides of the brushes  236 . It is noted that the configuration, shape and material of the cleaning apparatus of the embodiment mentioned above and shown in  FIGS. 3A to 3D  are examples instead of limitations, any equivalents, alternatives or modifications of the embodiment corresponding to the spirit of invention should be encompassed in the scope of the invention. 
     Similar to the susceptor  230  shown in  FIGS. 1 to 2B , the cleaning apparatus can be loaded on or removed from the movable frame  220  through the robot arm  240  with the fork  242 . In order to load and dispose the cleaning pad  234  on the movable frame  220 , the fork  242  drove by the robot arm  240  extends into the stages  235  of the cleaning pad  234  so as to lift up the cleaning pad  234 . Then the gate valve  211  is opened and the fork  242  carrying the cleaning pad  234  extends into the reaction chamber  210  to put the cleaning apparatus on the movable frame  220 . To remove the cleaning apparatus from the movable frame  220 , the fork  242  extends into the reaction chamber  210  after the gate valve  211  is opened. Then the fork  242  drove by the robot arm  240  extends into the stages  235  of the cleaning pad  234  so as to lift up the cleaning apparatus. Next the fork  242  carrying the cleaning apparatus retracts from the reaction chamber  210 . In order to load or remove the cleaning apparatus, the movable frame  220  may need to be moved vertically and to rotate so as to allow the fork  242  extending into the stages  235  of the cleaning pad  234 . 
       FIGS. 4A and 4B  illustrate the cleaning pad  234  with the brushes  236  arranged to form triangle patterns in accordance with two embodiments of the present invention. As shown in  FIGS. 4A and 4B , the cleaning pad  234  comprises three brushes  236  thereon, wherein the brushes  236  are arranged to form a triangle pattern. Moreover, the brushes  236  can extend outward to surpass the edge of the cleaning pad  234  so as to enlarge the cleaning range of the cleaning pad  234 . It is noted that the number and arrangement of the brushes  236  on the cleaning pad  234  in these embodiments are examples instead of limitations, any equivalents, alternatives or modifications of the embodiment corresponding to the spirit of invention should be encompassed in the scope of the invention. 
     The present invention utilizes a cleaning apparatus comprising a cleaning pad with a plurality of brushes thereon to remove residues within a reaction chamber of a semiconductor equipment. The cleaning pad has a shape and a configuration similar to a susceptor for holding a wafer which can be loaded on a rotor or a movable frame in a reaction chamber by a robot arm with a fork. That is, the cleaning apparatus used as an in-situ cleaning tool can be loaded and held on a movable frame just like a susceptor. The cleaning apparatus can then be moved and rotated to lean against and to clean a showerhead inside the semiconductor equipment. More details about configurations and operations of the cleaning apparatus according to embodiments of the invention will be further described in the following contents. 
       FIG. 5  depicts an in-situ cleaning operation via the cleaning apparatus according to embodiments of the invention. After deposition process, residues are usually formed within the reaction chamber. Particularly, many residues will accumulate on the lower surface of the showerhead  215 . In this embodiment, the cleaning apparatus is used to remove residues on the showerhead  215 . First of all, the cleaning apparatus is loaded and disposed on the movable frame  220  by the robot arm  240  with the fork  242 . Then the movable frame  220  with the cleaning apparatus is moved linearly and vertically by the linear transmission device  291  of the transmission device  290  so that the brushes  236  on the cleaning pad  234  lean against the showerhead  215 . Next the cleaning apparatus and the movable frame  220  are drove to rotate by the motor  292  and the gear assembly  293  so as to remove residues or other particles on the lower surface of the showerhead  215  and to clean the showerhead  215 . Moreover, suitable purge gases can be delivered into the reaction chamber  210  through the showerhead  215  to purge out residues, particles, or contaminants, etc. Furthermore, a high temperature baking process can also be performed inside the reaction chamber  210  for a period of time to further remove remaining residues, particles, or contaminants, etc. 
     By employing the present invention, it provides the capability of removing residue attached within the reaction chamber without the need opening the reaction chamber for manual maneuver. As the result, maintenance time is decreased and the quality of manufacture is improved. 
     The present invention contemplates and provides a method for cleaning semiconductor equipment. Although specific embodiments have been illustrated and described, it will be appreciated by those skilled in the art that various modifications may be made without departing from the scope of the present invention, which is intended to be limited solely by the appended claims.