Abstract:
A device for limiting travel of a valve including a body removably connected to a transfer module, a vacuum valve, or a reaction chamber, a travel limiting rod passing through the body to engage and limit travel of the valve, and wherein the body includes at least one mounting flange opposite the travel limiting rod.

Description:
FIELD OF THE DISCLOSURE 
       [0001]    This disclosure relates generally to semiconductor processing, and more particularly to an apparatus and method for safely locking out and tagging out a vacuum valve on a semiconductor reaction chamber. 
       BACKGROUND 
       [0002]    Semiconductor fabrication processes are typically conducted with the substrates supported within a chamber under controlled conditions. For many purposes, semiconductor substrates (e.g., wafers) are heated inside the process chamber. For example, substrates can be heated by direct physical contact with an internally heated wafer holder or “chuck.” “Susceptors” are wafer supports used in systems where the wafer and susceptors absorb heat. 
         [0003]    Some of the important controlled conditions for processing include, but are not limited to, pressure of the chamber, fluid flow rate into the chamber, temperature of the reaction chamber, temperature of the fluid flowing into the reaction chamber, and wafer position on the susceptor during wafer loading. 
         [0004]    Wafers are loaded through vacuum valves into the chamber with a robot. During operation, the vacuum valves facilitate a separation between the wafer transfer regions and the processing region (the reaction chamber). Advantageously, the vacuum valve is a simple gate valve style device that may operate pneumatically, hydraulically, or by other suitable mechanism. Inevitably the reaction chamber will need to be serviced or cleaned. In some of these instances, it may be necessary or advantageous to keep the vacuum valve in place while performing maintenance. In these cases, it is unsafe because the vacuum valve may be operable and crush/sever a finger or limb. 
       SUMMARY 
       [0005]    Various aspects and implementations are disclosed herein that relate to a reaction chamber with a vacuum valve lockout tagout apparatus. In one aspect, a device for limiting travel of a valve includes a body removably connected to a transfer module, a vacuum valve, or a reaction chamber, a travel limiting rod passing through the body to engage and limit travel of the valve, and wherein the body includes at least one mounting flange opposite the travel limiting rod. 
         [0006]    In one implementation, the at least one mounting flange may further include a locating aperture and a mounting aperture. The device may include at least two mounting flanges. The device may include a bottom wall extending perpendicular to the mounting flange. The bottom wall may further include a hole for receiving the travel limiting rod. The hole may be threaded. The travel limiting rod may be threaded. Only a portion of the travel limiting rod may be threaded. The bottom wall may further include a locking hole. The travel limiting rod may further include a plurality of holes which can be aligned with the locking hole. The travel limiting rod may further include a recessed portion on one end. The recessed portion may be engaged with a valve. The device may be removed from the transfer module, the vacuum valve, or the reaction chamber. The travel limiting rod may be rotatable in a first direction to restrict valve movement and rotatable in a second direction to permit valve movement. The base may further include a cutout for surrounding the valve. 
         [0007]    In another aspect, a method of locking out a vacuum valve includes the steps of mounting a body to the vacuum valve, positioning a travel limiting rod within a portion of the body, and moving the travel limiting rod to a position which restricts movement of the vacuum valve. 
         [0008]    In an implementation, the body may further include at least one locating aperture for connection with a transfer module. The travel limiting rod may be rotated into contact with the vacuum valve. The method may include the step of removing the body after performing a maintenance operation. The method may further include the step of locking the travel limiting rod with a secondary lock. 
         [0009]    This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. Furthermore, the claimed subject matter is not limited to implementations that solve any or all disadvantages noted in any part of this disclosure. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  illustrates a front view of the device for limiting travel of a valve mounted to a reaction chamber and vacuum valve. 
           [0011]      FIG. 2  illustrates a perspective view of the travel limiting device. 
           [0012]      FIG. 3  illustrates a view of the travel limiting device taken generally about line  3 - 3  in  FIG. 1 . 
           [0013]      FIG. 4  illustrates a front view of the travel limiting device in the unlocked positioned and the travel limiting rod in the unlocked position. 
           [0014]      FIG. 5  illustrates a front view of the travel limiting device and travel limiting rod in the locked position. 
           [0015]      FIG. 6  illustrates a sectional view of the vacuum valve taken generally about line  6 - 6  in  FIG. 5 . 
           [0016]      FIG. 7  illustrates a sectional view of a secondary lock taken generally about line  7 - 7  in  FIG. 5 . 
       
    
    
     DETAILED DESCRIPTION 
       [0017]    The present aspects and implementations may be described in terms of functional block components and various processing steps. Such functional blocks may be realized by any number of hardware or software components configured to perform the specified functions and achieve the various results. For example, the present aspects may employ various sensors, detectors, flow control devices, heaters, and the like, which may carry out a variety of functions. In addition, the present aspects and implementations may be practiced in conjunction with any number of processing methods, and the apparatus and systems described may employ any number of processing methods, and the apparatus and systems described are merely examples of applications of the invention. 
         [0018]      FIGS. 1-7  illustrate various views of a reaction chamber assembly  10  having a reactor  12  with a vacuum valve  14  controlling access to the reactor  12  through vacuum valve opening  16 . Vacuum valve  14  includes a mechanical system  18  for operating the vacuum valve. The mechanical system may include a gate  17  with an upper portion  17 A passing into vacuum valve opening  16  and a lower portion  17 B connected to a valve pin  66 . Valve pin  66  is connected to the gate  17  and mechanical system  18  and extends through a hole  19  in the bottom of the mechanism. 
         [0019]    A travel limiting device  20  includes a travel limiting body  21  with a cutout  22  and valve tabs  24  arranged around the vacuum valve once mounted to the reactor chamber assembly. The body  21  may also include mounting flanges  25  having mounting apertures  26  with alignment apertures  28  and securing apertures  30  arranged to receive a mounting pin  56  with mounting pin head  58  therein. Mounting flanges  25  also include a top end  32  opposite sidewalls  35  and a bottom wall  34  with a locking aperture  36  in the bottom wall and a threaded sleeve coaxially aligned with locking aperture  36 . Still further, bottom wall  34  may also include a tag out aperture  38  for receiving a locking device. 
         [0020]    A travel limiting rod  40  includes a non-threaded portion  42 , a threaded portion  44 , a handle  46 , and a plurality of tag out apertures  48 . The travel limiting rod  40  moves vertically in the directions associated with arrows  64  and  65  by rotating handle  46  to engage the threaded portion  44  of the travel limiting rod with the locking aperture  36  of body  21 . The travel limiting rod  40  may also include a recessed portion  50  at the top end of the rod and is arranged to contact valve pin  66  and ensure consistent contact between the travel limiting rod and the vacuum valve so that the reaction chamber may be safely and properly locked out during maintenance and other necessary work. 
         [0021]    Body  21  may also include a cavity  52  formed in part by bottom wall  34 , sidewalls  35 , and valve tab inner surfaces  54 . Valve tab inner surfaces  54  are positioned to contact or at least be in close proximity to the vacuum valve body. 
         [0022]    Moving to  FIG. 3 , mounting pin  56  is shown in greater detail with the mounting pin head  56  positioned outward of a holding area  60  and arranged to receive the body  21  of the travel limiting device. As can be seen, a reactor body  62  receives the mounting pin  56  therein and contacts a rear surface of the travel limiting device. 
         [0023]      FIGS. 5 and 7  illustrate views of the tagout  68  having a plurality of tagout apertures  70  arranged to receive a lock  72  therein. Further, a lockout clasp  74  is shown attached through limiting rod tagout aperture and tagout aperture  38 . Accordingly, when lockout clasp  74  is closed in position, lock  72  can be used to prevent clock  74  from opening and thereby limit rotational movement of travel limiting rod  40 . 
         [0024]    In operation, body  21  may be positioned on mounting pins  56  as shown in  FIGS. 1 and 3 . Next, travel limiting rod  40  is moved vertically in the direction associated with arrow  64  by rotating handle  46  to provide vertical displacement of recessed portion  50  through hole  19  as seen in  FIG. 4 .  FIG. 5  next shows the vertical displacement of travel limiting rod  40  in the fully upward position as identified by arrow  65 . In this manner, upper portion  17 A of the gate is locked in the closed position. The interaction between recessed portion  50  and valve pin  66  prevents vertical motion of the valve in the downward direction unless travel limiting rod  40  is rotated.  FIG. 7  illustrates how travel limiting rod rotation is limited. Specifically, tagout clasp  74  is passed through travel limiting rod tagout aperture  48  in the handle  46  and tagout aperture  38  in body  21  and prevents relative rotational movement between the body and the handle. Accordingly, the tagout device prevents the travel limiting rod from rotating and thereby allowing the gate valve to move which keeps the device safe during maintenance processes. 
         [0025]    These and other embodiments for methods and apparatus for a lockout tagout device therein may incorporate concepts, embodiments, and configurations as described with respect to embodiments of apparatus for measuring devices described above. The particular implementations shown and described are illustrative of the invention and its best mode and are not intended to otherwise limit the scope of the aspects and implementations in any way. Indeed, for the sake of brevity, conventional manufacturing, connection, preparation, and other functional aspects of the system may not be described in detail. Furthermore, any connecting lines shown in the various figures are intended to represent exemplary functional relationships and/or physical couplings between the various elements. Many alternative or additional functional relationship or physical connections may be present in the practical system, and/or may be absent in some embodiments. Further, various aspects and implementations of other designs may be incorporated within the scope of the disclosure. 
         [0026]    As used herein, the terms “comprises”, “comprising”, or any variation thereof, are intended to reference a non-exclusive inclusion, such that a process, method, article, composition or apparatus that comprises a list of elements does not include only those elements recited, but may also include other elements not expressly listed or inherent to such process, method, article, composition or apparatus. Other combinations and/or modifications of the above-described structures, arrangements, applications, proportions, elements, materials or components used in the practice of the present invention, in addition to those not specifically recited, may be varied or otherwise particularly adapted to specific environments, manufacturing specifications, design parameters or other operating requirements without departing from the general principles of the same.