Abstract:
A separation module is provided having a housing, a filter within the housing and at least one outlet and one inlet. The outlet and inlet are positioned to mate with fittings of a pump housing. A stationary receptor positioned between the pump housing and the separation module has a pivot line and two shelves on its outer surface which permit fitting the separation module in a stationary receptor adjacent the pumping housing.

Description:
RELATED APPLICATIONS  
       [0001]     This application is a continuation of U.S. application Ser. No. 10/489,587, filed Mar. 12, 2004 which is the U.S. National Stage of International Application No. PCT/US02/29107, filed on Sep. 13, 2002, published in English, which claims the benefit of U.S. Provisional Application No. 60/322,002, filed on Sep. 13, 2001. The entire teachings of the above applications are incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     This invention relates to a separation module for purifying a fluid. Fluid separation devices having an easily replaceable and disposable fluid separation module have been used to control contamination in industrial processes for many years. Such devices are an integral part of the manufacture of many products including pharmaceuticals, food stuffs and beverages. However, nowhere is the need for effective contamination control greater than in the semiconductor fabrication industry. With circuit details in the submicron range and with further feature size reductions inevitable, the need for control of particulate, ionic, organic and other contaminants in the semiconductor process fluids is essential. Also, because semiconductor devices are fabricated in clean rooms, it is important to minimize the potential of contaminating the manufacturing environment. For this reason, disposable fluid separation devices are preferable in semiconductor fabrication processes in order to minimize contamination of the process lines as well as the clean room.  
         [0003]     Examples of semiconductor process fluids which are processed at the point of use (POU) include those chemicals used in photolithographic processing (photochemicals). Photochemicals include materials such as primers, adhesion promoters, photoresists, edge bead removers, antireflective coatings, developers, dielectrics, and the like. Such chemicals are commonly dispensed onto the silicon wafer by a specialized pump and subsequently dispersed into a uniform thin film using a process called spin coating. The purity of these chemicals at the POU is essential to producing acceptable product yields.  
         [0004]     Fluid separation devices are in general of two types. In the first type, the separation element such as a filter is a replaceable component, while the pressure vessel which houses the element, i.e., the housing, is reusable. The housing also contains appropriate fluid connections to the rest of the fluid processing system. Replacing the fluid separation element requires opening the housing, removing the separation element, installing the replacement separation element into the housing and closing the housing. There are many disadvantages to this type of fluid separation device. First, the replacement operation is time consuming, especially if access to the housing is restricted. Secondly, because the housing contains a quantity of the fluid being processed and because the fluid separation element is usually saturated with the fluid, spillage of the fluid usually occurs. In the case of hazardous fluids, spills can be a threat to the well-being of personnel in the area as well as potentially damaging to nearby equipment and facilities. Finally, the opening of the housing exposes the internal surfaces of the fluid processing system to unwanted contamination from the surrounding environment.  
         [0005]     The second type of separation device is one in which the separation element is permanently attached to the housing, which also contains appropriate fluid connections to the rest of the fluid processing system, to form an integrated module. In this case, replacement involves disconnecting the entire separation module from the fluid processing system and reconnecting a replacement module to the system. In this manner, replacement is easier, exposure of the operator to hazardous chemicals is minimized and the reliability of the connection is significantly improved. The type of separation device is referred to as a disposable module, since the whole module is removed and disposed of whenever the separation element requires replacement regardless of what connector design is employed. Disposable modules usually require that multiple connections be made sequentially, a minimum of two connections, and more typically three or four. Threaded fasteners are cumbersome and sometimes difficult to engage; factors which involve the subsequent consumption of additional time and effort. Furthermore, the module has to be held in place while the connections are being made, which makes the connection event even more difficult since it requires performing two actions at the same time (i.e., holding the module in place and attaching each connector sequentially). Finally, in those applications in which the permanent connections to the fluid processing system are not rigid, as for example, when the flexible tubing is used, liquid has a tendency to be discharged as the connections disengage. All of these problems exacerbate the time and effort required to replace a disposable module, in addition to still allowing for exposure of personnel to hazardous materials, and contamination of the manufacturing environment.  
         [0006]     For these reasons, some disposable separation modules have been designed with features that allow them to be connected quickly and easily to the fluid processing system in a “quick-connect” fashion. These types of quick-connect modules provide for a set of connectors that sealingly engage with a single, simple stroke or action, to a mating set of connectors attached to a reusable substrate. Different types of mechanisms have been designed to accomplish quick-connect retention, all of which heretofore have required some form of relative motion between the male connector and its female counterpart, most commonly a twisting action.  
         [0007]     It has also been proposed to provide a separation module in a system for dispensing a filtered fluid composition wherein the separation module is introduced into a pivotable housing to effect a desired connection. The pivotable housing is expensive and is subjected to breakage over time due to excessive use.  
         [0008]     Accordingly, it would be desirable to provide a separation module which can be replaced in a fluid separation system without the need of a pivotable housing.  
       SUMMARY OF THE INVENTION  
       [0009]     The separation module of this invention fits into a stationary receptor having a shelf which functions as a pivot line and a slot which receives and retains a latch of the separation module. The separation module includes a curved surface which fits onto the pivot line of the stationary receptor and a latch which cooperates with the slot of the stationary receptor to retain the separation module within the stationary receptor. The separation module includes a filter positioned within a housing of the separation module and fittings which connect a source of fluid to be purified to a point of use for the fluid being purified within the separation module. In one embodiment, the separation module is positioned in a portable manifold having fluid fittings which permit the use of the separation module in fluid transfer systems having a variety of functions. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]      FIG. 1  is a perspective view of a separation module of this invention.  
         [0011]      FIG. 2  is a perspective view of a stationary receptor utilized in conjunction with the separation module of  FIG. 1 .  
         [0012]      FIGS. 3   a,    3   b,    3   c  and  3   d  are side view illustrating the use of a latch of the separation module of  FIG. 1 .  
         [0013]      FIG. 4  is a side view of the separation module of  FIG. 1  in the stationary receptor of  FIG. 2 .  
         [0014]      FIG. 5  is a perspective view of the apparatus of  FIG. 4  attached to a pump housing.  
         [0015]      FIG. 6  illustrates an alternative separation module of this invention.  
         [0016]      FIG. 7  illustrates an alternative separation module of this invention.  
         [0017]      FIG. 8  is a perspective view of a portable stationary module and separation module of this invention.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0018]     The separation module of this invention is useful for purifying a fluid from a fluid dispensing system which includes a pump. The fluid dispensing system can includes a single pump or a plurality of pumps such as a two pump system comprising a dispensing pump and a feed pump. Such a system, when dispensing a fluid, includes the separation module of this invention having a separation element which separates unwanted components of the fluid from the desired fluid composition.  
         [0019]     The present invention will be particularly described herein with reference to a two pump fluid dispensing system including a feed pump, a dispensing pump and a separation module having a particular configuration of inlet means and outlet means. However, it is to be understood that the present invention can be utilized in a fluid dispensing system having a separation module regardless of the outer surface configuration of inlet means and outlet means on the surface of the separation module.  
         [0020]     Referring to  FIG. 1 , the separation module  10  of this invention includes a housing  12  for a filter construction such as a pleated filter, a depth filter, hollow fibers or the like. Ports  14 ,  16  and  18  fit over mating fittings,  15 ,  17  and  19  ( FIG. 4 ). Housing  66  ( FIG. 5 ) which contains a feed pump and a dispense pump such as that disclosed in U.S. Pat. No. 5,263,069 which is incorporated herein by reference. Port  14  can be an inlet for fluid to be filtered. Port  16  can be an outlet for retentate. Port  18  can be an outlet for filtered fluid directed to a point of use. The separation module  10  includes a pivot surface  20  which extends substantially the complete width of the separation module  10  and two flanges  22  (one shown) which are positioned on opposing surfaces of the separation module  10  and which are attached to walls  24  and  26 .  
         [0021]     The separation module  10  is provided with a latch  31  having a vertical arm  32 , a hook  33  and a leaver  35 . The latch  31  is secured to the separator module  10  such as by being molded with the walls of slot  37 . The slot  37  permits movement of latch  31  when a force is applied to lever  35 , such as manual force.  
         [0022]     Referring to  FIG. 2 , the stationary receptor  36  includes a top surface  38  having holes  40 ,  42  and  44  through which fittings  15 ,  17  and  19  ( FIG. 4 ) from a manifold extend. The stationary receptor  36  includes a flange  46  having an opening  47  which cooperates with vertical arm  32  and hook  33  of latch  31 . The stationary receptor  36  also includes shelves  50  and  52  onto which flanges  22  of separation module  10  slide, as well as receptor pivot surface  54  onto which pivot surface  20  fits.  
         [0023]     Referring to  FIGS. 3   a,    3   b,    3   c  and  3   d,  the latch  31  in its initial position is shown in  FIG. 3   a.  As shown in  FIG. 3   b,  a force in the direction of the arrow causes hook  33  to move away from flange  46 . As shown in  FIG. 3   c,  the latch  31  is moved upwardly by moving filtrate module  10  upwardly so that the hook  33  fits onto flange  46 . This latch position fixes the filtration module  10  to stationary module  36 . As shown in  FIG. 3   d,  the hook  33  is removed from flange  46  by applying a force to lever  35  as shown by the arrow. When latch  31  in the position shown in  FIG. 3   d,  separation module  10  can be removed from stationary receptor  36 .  
         [0024]     As shown in  FIGS. 2 and 4 , separation module  10  is slid into stationary receptor  36  onto slides  50  and  52  until pivot line  20  is positioned on pivot surface  54 . When separation module  10  is so positioned, ports  14 ,  16  and  18  are positioned to fit over fittings  15 ,  17  and  19  when separation module  10  is rotated upwardly as indicated by arrow  55 . By virtue of this upward movement, arm  32  is locked onto flange  46  and hook  33  extends through the opening  47 . This, in turn, locks separation module  10  into stationary receptor  36  so that leak-free fluid transfer can be affected between ports  14 ,  16  and  18  and fittings  15 ,  17  and  19 .  
         [0025]     As shown in  FIG. 5 , the stationary receptor  36  is attached to a pump housing containing one or more a plurality of pumps in a manner well known in the art. The fittings  14 ,  16  and  18  are sealed to mating fittings such as described above.  
         [0026]     As shown in  FIG. 6 , the separation module  10  can be provided with a latch  28  comprising two arms  30  and  31 . Arm  31  is provided with lip  34  which cooperates with the bracket of  FIG. 2  as described below. The arms  30  and  31  are sufficiently flexible so that the arm  31  can be pushed by arm  30 , which in turn, is pushed manually sequentially in order to engage or remove arm  31  from contact with flange  46  of bracket  36  and thereby to permit removal of separation module  10  from bracket  36 .  
         [0027]     An alternative embodiment of a separation module of this invention is shown in  FIG. 7 . The separation module  10   a  having ports  14   a,    16   a  and  18   a,  also is provided with two shelves  22  and a pivot line  20  in the manner described above with reference to  FIG. 1 . The latch  70  includes a lip  72  and an arm  74 . The lip  72  is configured to fit into a stationary receptor and the lever  74  permits application of manual force in order to remove lip  72  from the stationary receptor thereby to install and remove the separation module  10   a  from the stationary receptor in the manner described above with the reference to  FIGS. 3   a - 3   d.    
         [0028]     Referring to  FIG. 8 , an embodiment of this invention is illustrated which comprises a portable unit of separation module  76  and the stationary receptor  78  that is portable. The separation module  76  and stationary receptor  78  are joined by latch  31  in the manner described above with reference to  FIGS. 3   a - 3   d.  The stationary receptor  78  is provided with fittings  80 ,  82  and  84  which can be mated with a pumping apparatus (not shown). The stationary receptor  78  is joined to a mounting  88  that can be mounted to a wall  90  by a latch  92 . This embodiment facilitates installation of stationary receptor  78 . The stationary receptor  78  can include a valve  81  having a manually activated apparatus lever  83  for opening or closing the valve  81  to permit or prevent fluid transfer through fittings.