Abstract:
A fluid delivery system that includes flow substrates and manifolds that minimize the number of fluid conduit ports and seals needed to build standardized fluid delivery sticks. Each flow substrate has a component attachment surface with one or more component conduit ports and an associated plurality of fastener apertures. Some flow substrates incorporate a transverse manifold connection conduit port on a surface opposite the component attachment surface. Fastener apertures associated with the transverse manifold connection conduit port are accessible adjacent to installed fluid handling components. Transverse connection between fluid delivery sticks use a welded assembly of fluid conduits to provide a transverse connecting lower layer which is sealingly retained by fasteners inserted from above through apertures associated with the transverse manifold connection conduit port. Flow substrates for each fluid delivery stick are fastened to a standardized bracket and each fluid delivery stick arrangement can be assembled and tested as an integrated subassembly.

Description:
RELATED APPLICATIONS 
     This application claims priority under 35 U.S.C. §119(e) to U.S. Provisional Application Ser. No. 61/178,286, entitled “FLUID DELIVERY SUBSTRATES FOR BUILDING REMOVABLE STANDARD FLUID DELIVERY STICKS,” filed on May 14, 2009, which is herein incorporated by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention is directed to fluid delivery systems, and more particularly to surface mount fluid delivery systems for use in the semiconductor processing and petrochemical industries. 
     2. Discussion of the Related Art 
     Fluid delivery systems are used in many modern industrial processes for conditioning and manipulating fluid flows to provide controlled admittance of desired substances into the processes. Practitioners have developed an entire class of fluid delivery systems which have fluid handling components removably attached to flow substrates containing fluid pathway conduits. The arrangement of such flow substrates establishes the flow sequence by which the fluid handling components provide the desired fluid conditioning and control. The interface between such flow substrates and removable fluid handling components is standardized and of few variations. Such fluid delivery system designs are often described as modular or surface mount systems. Representative applications of surface mount fluid delivery systems include gas panels used in semiconductor manufacturing equipment and sampling systems used in petrochemical refining. The many types of manufacturing equipment used to perform process steps making semiconductors are collectively referred to as tools. Embodiments of the present invention relate generally to fluid delivery systems for semiconductor processing and specifically to surface mount fluid delivery systems. Aspects of the present invention are applicable to surface mount fluid delivery system designs whether of a localized nature or distributed around a semiconductor processing tool. 
     Industrial process fluid delivery systems have fluid pathway conduits fabricated from a material chosen according to its mechanical properties and considerations of potential chemical interaction with the fluid being delivered. Stainless steels are commonly chosen for corrosion resistance and robustness, but aluminum or brass may be suitable in some situations where cost and ease of fabrication are of greater concern. Fluid pathways may also be constructed from polymer materials in applications where possible ionic contamination of the fluid would preclude using metals. The method of sealingly joining the fluid handling components to the flow substrate fluid pathway conduits is usually standardized within a particular surface mount system design in order to minimize the number of distinct part types. Most joining methods use a deformable gasket interposed between the fluid component and the flow substrate to which it is attached. Gaskets may be simple elastomeric O-Rings or specialized metal sealing rings such as seen in U.S. Pat. No. 5,803,507 and U.S. Pat. No. 6,357,760. Providing controlled delivery of high purity fluids in semiconductor manufacturing equipment has been of concern since the beginning of the semiconductor electronics industry and the construction of fluid delivery systems using mostly metallic seals was an early development. One early example of a suitable bellows sealed valve is seen in U.S. Pat. No. 3,278,156, while the widely used VCR® fitting for joining fluid conduits is seen in U.S. Pat. No. 3,521,910, and a typical early diaphragm sealed valve is seen in U.S. Pat. No. 5,730,423 for example. The recent commercial interest in photovoltaic solar cell fabrication, which has less stringent purity requirements than needed for making the newest microprocessor devices, may bring a return to fluid delivery systems using elastomeric seals. 
     A collection of fluid handling components assembled into a sequence intended for handling a single fluid species is frequently referred to as a gas stick. The equipment subsystem comprised of several gas sticks intended to deliver process fluid to a particular semiconductor processing chamber is often called a gas panel. During the 1990s several inventors attacked problems of gas panel maintainability and size by creating gas sticks wherein the general fluid flow path is comprised of passive metallic structures, containing the conduits through which process fluid moves, with valves and like active (and passive) fluid handling components removably attached thereto. The passive fluid flow path elements have been variously called manifolds, substrates, blocks, and the like, with some inconsistency even within the work of individual inventors. This disclosure chooses to use the terminology flow substrate to indicate fluid delivery system elements which contain passive fluid flow path(s) that may have other fluid handling devices mounted there upon. 
     Many semiconductor manufacturing processes have fluid delivery requirements amenable to quite regular gas panel designs. Such gas panels are comprised of several nearly identical gas sticks conducting fluid in a generally longitudinal direction, from stick inlet to stick outlet, the sticks differing mainly with regard to particular fluid species, flow rates, and such other matters. Selectively chosen transverse connections between gas sticks are used to combine fluid flows for delivery to the processing chamber, or provide purging and vacuum connections, or similar functions known in the art. A process equipment manufacturing environment having recurring need for large quantities, but relatively few types, of gas sticks gives rise to a material management concept sometimes referred to as “standard stick” designs. Embodiments of the present invention are directed to lower cost flow substrate and standard stick bracket designs which enhance the ease of installing, or replacing, complete gas stick subassemblies in a gas panel subsystem while making standard stick designs less expensive. 
     Some examples of regularized gas panels are described in U.S. Pat. No. 5,836,355, U.S. Pat. No. 6,283,155, and U.S. Pat. No. 6,302,141 wherein the component bearing substrate block parts have component ports on one surface, and one or more manifold ports on the opposite surface, whereby transverse connection between gas sticks is provided through a second lower layer of block parts in sealing registration with the manifold port(s). In these designs it is not feasible to remove a single gas stick intact from the gas panel because one or more active components must first be removed to allow access to the fasteners which couple together the first and second layers of substrate blocks. A similar problem exists in the gas stick of U.S. Pat. No. 6,769,463 which uses a welded assembly of fluid conduits to provide the transverse connecting second layer instead of a bolted assembly of blocks. 
     U.S. Pat. No. 5,992,463 describes a regularized gas panel wherein the component bearing manifold (substrate) parts have all fluid ports only in a common plane whereby transverse connection between gas sticks is provided through bridging components directly attached to ports in that common plane as described in U.S. Pat. No. 6,435,215. Replacement of a gas stick requires removal of the appropriate bridging component(s) but does not necessitate disruption of the gas stick itself. Similar use of bridging components may be seen in U.S. Pat. No. 6,293,310, U.S. Pat. No. 6,374,859, and U.S. Pat. No. 6,394,138 for example. 
     SUMMARY OF THE INVENTION 
     Embodiments of the present inventive flow substrate and standard stick bracket designs minimize the total number of fluid conduit ports and seals needed to build standardized fluid delivery sticks. Each flow substrate has a component attachment surface with one or more component conduit ports and an associated plurality of fastener apertures. Some flow substrates incorporate a transverse manifold connection conduit port on a surface opposite the component attachment surface and fastener apertures associated with the transverse manifold connection conduit port are accessible adjacent to installed components. Transverse connection between fluid delivery sticks preferably uses a welded assembly of fluid conduits to provide a transverse connecting lower second layer which is sealingly retained by fasteners inserted from above through the apertures associated with the transverse manifold connection conduit port. 
     The flow substrates for each fluid delivery stick are securely fastened to a standardized stick bracket providing firm mechanical alignment and thereby obviating need for any interlocking flange structures among the flow substrates. The absence of interlocking flange structures provides reduced cost through lessened machining and similarly less use of high purity grade metal constituting the flow substrates. Each standardized fluid delivery stick arrangement can be assembled and tested as a rigid free-standing subassembly before installation in the fluid delivery panel. Installation of the standardized stick only requires insertion and tightening of fasteners associated with the transverse manifold connection conduit port(s) and attachment of the standardized stick bracket to the fluid delivery panel backplane. Likewise, removal and replacement of a standardized stick involves only the complete unit without need to remove any individual element of the standardized stick. 
     The standardized stick bracket secures the standard stick to the fluid delivery panel backplane and thereby holds adjacent standardized sticks in correct transverse alignment to enable connection between bottom located flow substrate transverse manifold connection conduit ports and corresponding ports in the underlying transverse oriented manifold(s). 
     The standardized stick bracket is preferably unitary and can be formed of folded heavy gage sheet metal, extruded or die cast aluminum, or similar suitable structural design. The flow substrate configurations may be adjusted for use with valves having symmetric port placement (e.g., W-Seal™ devices) or asymmetric port placement (e.g., standard “C-Seal” devices) on the valve (or other fluid handling component) mounting face, but asymmetric designs are mostly shown herein because such devices are most commonly available in the semiconductor equipment marketplace. A further cost saving aspect of the inventive substrates is the use of only 2-port valves to accomplish all fluid routing functions thereby lowering standardized stick cost by avoiding more expensive 3-port valves. 
     The flow substrates of the inventive standard stick design are purposely made with all ports and conduits having their corresponding axis of symmetry normal to the plane of the substrate face which is respectively pierced. Such flow substrate designs may be machined using less sophisticated machine tools than required for the angle drilled holes seen in U.S. Pat. No. 6,394,138 for example. Injection molding and die casting fabrication methods will similarly be simplified by having all passages normal to the exterior faces. Fluid pathway conduits within a particular flow substrate need not be of identical cross sectional area and may be optimized according to function. 
     In accordance with one aspect of the present invention, a fluid delivery stick is provided. The fluid delivery stick comprises a fluid delivery stick bracket, a plurality of flow substrates disposed on a surface of the fluid delivery stick bracket, and a manifold. The plurality of flow substrates includes at least one flow substrate having a flow substrate body and a plurality of component conduit ports formed in a component attachment surface of the flow substrate body. The plurality of component conduit ports includes first and second component conduits ports that are fluidly connected by a first fluid pathway formed in the flow substrate body and third and fourth component conduit ports that are fluidly connected by a second fluid pathway formed in the flow substrate body. The first and second fluid pathways extend between the first and second component conduit ports and the third and fourth component conduit ports along a first axis. The at least one flow substrate further includes a manifold connection conduit port formed in a connection attachment surface of the flow substrate body that opposes the component attachment surface, and a third fluid pathway formed in the flow substrate body that fluidly connects one of the second and third component conduit ports to the manifold connection conduit port. The third fluid pathway extends between the one of the second and third component conduit ports and the manifold connection conduit port along a second axis that is generally transverse to the first axis. The manifold has a manifold body and a manifold conduit port formed in a substrate attachment surface of the manifold body. The manifold includes a tube stub connection extending from the manifold body in a direction parallel to one of the first axis and the second axis that is fluidly connected to the manifold conduit port by a manifold fluid pathway formed in the manifold body. The manifold is constructed and arranged to be suspended below the at least one substrate and fastened to the flow substrate body by a pair of fasteners that are inserted through the flow substrate body from the component attachment surface of the flow substrate body and that maintain the manifold conduit port in sealing engagement with the manifold connection port. 
     In accordance with one embodiment, the manifold is further constructed and arranged to be suspended below the at least one substrate without contacting the fluid delivery stick bracket. In accordance with a further aspect of this embodiment, the fluid delivery stick further comprises a fluid handling component fastened to the component attachment surface of the at least one substrate, the fluid handling component having a first component port in sealing engagement with the second component conduit port and a second component port in sealing engagement with the third component conduit port. In accordance with this embodiment, the fluid delivery stick bracket is mounted to a support surface by a plurality of fasteners, and the fluid delivery stick bracket, the fluid handling component, and each of the plurality of flow substrates can be dismounted from the support surface as an integral unit by removing only the plurality of fasteners and the pair of fasteners that maintain the manifold conduit port in sealing engagement with the manifold connection port. 
     In accordance with an aspect of the present invention, the manifold includes a plurality of tube stub connections extending from the manifold body and fluidly connected to the manifold conduit port by the manifold fluid pathway. The plurality of tube stub connections includes a first tube stub connection extending from the manifold body in a direction parallel to the first axis and a second tube stub connection extending from the manifold body in a direction parallel to the second axis. 
     In accordance with another aspect of the present invention, the first and second fluid pathways can have a first diameter and the third fluid pathway can have a second diameter that is larger than the first diameter. 
     In accordance with yet another aspect of the present invention, each of the plurality of component conduit ports is formed by machining from the component attachment surface into the flow substrate body, and each of the first and second fluid pathways is formed by machining from the connection attachment surface. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component that is illustrated in various figures is represented by a like numeral. For purposes of clarity, not every component may be labeled in every drawing. In the drawings: 
         FIG. 1A  illustrates a top elevation view of a conventional modular fluid flow substrate design; 
         FIG. 1B  illustrates a bottom elevation view of the conventional modular fluid flow substrate design illustrated in  FIG. 1A ; 
         FIG. 2A  illustrates a cross-sectional view and an isometric view of a standardized fluid delivery stick in accordance with one embodiment of the present invention; 
         FIG. 2B  illustrates an isometric view of a standardized fluid delivery stick in accordance with another embodiment of the present invention; 
         FIG. 3A  illustrates a collection of modular flow substrates and modular manifolds in accordance with a first embodiment of the present invention for use with fluid handling components having asymmetric port placement (e.g., standard C-seal components); 
         FIG. 3B  illustrates plan and elevation views of a variety of different flow substrates in accordance with the embodiment of  FIG. 3A  for use at higher fluid flow rates; 
         FIG. 4  illustrates exploded plan and cross-sectional views of an exemplary flow substrate selected from  FIG. 3B ; 
         FIG. 5  illustrates a limited collection of modular flow substrates in accordance with the first embodiment depicted in  FIG. 3A  for use at higher fluid flow rates and which may be positioned at the beginning or end of a standardized fluid delivery stick; 
         FIGS. 6A and 6B  illustrate plan and elevation views of a variety of different flow substrates in accordance with the embodiment of  FIG. 3A  for use at lower fluid flow rates; 
         FIG. 7  illustrates exploded plan and cross-sectional views of an exemplary flow substrate for use at lower fluid flow rates; 
         FIG. 8A  illustrates plan and cross-sectional views of an exemplary alternative design flow substrate for use at lower fluid flow rates, in which the fluid pathway associated with the manifold connection conduit port has an increased diameter useful for pump/purge applications; 
         FIG. 8B  illustrates a cut-away view of the exemplary flow substrate of  FIG. 8A ; 
         FIG. 9A  illustrates a limited collection of modular flow substrates and modular manifolds in accordance with a second embodiment of the present invention for use with fluid handling components having symmetric port placement (e.g., W-Seal™ components); 
         FIG. 9B  illustrates plan and elevation views of a flow substrate in accordance with the embodiment of  FIG. 9A  for use at higher fluid flow rates; 
         FIG. 10  illustrates a limited collection of modular flow substrates in accordance with the second embodiment depicted in  FIG. 9A  for use at higher fluid flow rates in which the flow substrates include flow substrate mounting apertures that are aligned with one another in accordance with one embodiment of the present invention; 
         FIG. 11A  illustrates a standardized fluid delivery stick bracket with offset flow substrate mounting apertures in accordance with one embodiment of the present invention; and 
         FIG. 11B  illustrates a standardized fluid delivery stick bracket with aligned flow substrate mounting apertures in accordance with another embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     This invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having,” “containing,” “involving,” and variations thereof herein, is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. 
     It should be appreciated that the fluid materials manipulated in the fluid delivery panel standardized sticks of the present invention may be a gaseous, liquid, or vaporous substance that can change between liquid and gas phase dependent upon the specific temperature and pressure of the substance. Representative fluid substances may be a pure element such as argon (Ar), a vaporous compound such as boron trichloride (BC13), a mixture of normally liquid silicon tetrachloride (SiC14) in carrier gas, or an aqueous reagent. 
       FIG. 1  illustrates a conventional modular fluid flow substrate design such as described in U.S. Pat. No. 6,394,138, which is incorporated by reference herein, in which  FIG. 1A  is an elevation view of the top surface of the flow substrate and  FIG. 1B  is an elevation view of the bottom surface of the flow substrate. Adjacent flow substrates  100  are interlocked to one another using a tongue and pocket design. This flow substrate design is commonly referred to in the semiconductor processing industry as “K1s.” 
     As shown, the flow substrate  100  is formed from a solid block of material (such as stainless steel) and includes a component attachment surface  105  to which a fluid handling component (such as a valve, pressure transducer, filter, regulator, etc.) is attached. A single V-shaped (or U-shaped) fluid passageway (not shown) extends between component conduit ports  120  and  121 . The port of a first fluid handling component is fluidly connected to component conduit port  120  using fasteners that extend through the base of the first fluid handling component and into fastening apertures  110   a ,  110   b ,  110   c , and  110   d . As shown in  FIG. 1A , the flow substrate  100  includes a pair of counter-bored mounting holes  130  that extend through the flow substrate for securing the flow substrate  100  to a support surface, a first pair of apertures  150  each to receive a respective dowel pin (not shown) that is used to align one flow substrate  100  with another adjacent flow substrate, and a helium leak port  125 . 
     As can be seen in  FIG. 1B , counter-bored mounting holes  130  extend through the flow substrate to the surface  115  opposite the component attachment surface  105 . A pair of attachment holes  131  is formed in a lower surface of the pocket region (not visible in  FIG. 1A ) of the flow substrate  100  and extend through the flow substrate  100  to the surface  115 . A pair of internally threaded attachment bores  132  is formed in an under-surface of the tongue region of the flow substrate  100  each to accommodate the shank of a threaded fastener which extends through aperture  131  and secures one flow substrate to another adjacent flow substrate. A second pair of apertures  151  is formed in the lower surface of the pocket region, each to receive a respective dowel pin (not shown) that is used to align one flow substrate  100  with another adjacent flow substrate. The port of a second fluid handling component is fluidly connected to component conduit port  121  using fasteners that extend through the base of the second fluid handling component and into corresponding fastening apertures  110   a ,  110   b ,  110   c , and  110   d , of the adjacent second flow substrate. The flow substrate  100  also includes a pair of apertures  140  that are drilled completely through the flow substrate in a longitudinal direction and which may receive a cartridge-type heater, as known in the art. 
     The design of the fluid flow substrate described with respect to  FIG. 1  above has been commercially successful and incorporates a number of features that allow it to be used in a number of different ways and in a wide variety of installations. However, many of these features may not be used in certain installations, and thus add cost and complexity. For example, the interlocking tongue and pocket design uses a great deal of raw material (e.g., high quality stainless steel) that is ultimately machined away. Moreover, many of the features, such as the counter-bored mounting holes  130  and mounting holes  131  (with associated bores  132 ) that permit the flow substrates to be self supporting and interlocking come with an associated cost of machining that may not be used in certain installations. Other features, such as the apertures  150 ,  151  to receive dowel pins add machining and assembly costs, and the apertures  140  to receive a cartridge heater may not be used in certain installations. Further, although not shown in  FIG. 1 , this design makes frequent use of 3-port valves, which are more expensive to purchase and assemble relative to the more common and less expensive 2-port valves. 
     Embodiments of Applicant&#39;s invention are directed to a modular surface mount fluid delivery system that overcomes one or more of the disadvantages noted above. In accordance with one aspect of the present invention, a modular surface mount fluid delivery system is provided that includes at least one modular surface mount fluid delivery stick, but more typically a plurality of modular surface mount fluid delivery sticks. Each modular surface mount fluid delivery stick includes a plurality of modular surface mount flow substrates, at least one, and more typically, a plurality of modular manifolds, and a mounting bracket to which the flow substrates are mounted. In accordance with one aspect of the present invention, the mounting bracket may have a standardized mounting-hole pattern that permits its use with a variety of flow substrates in an interchangeable manner. For example, in accordance with one embodiment, the standardized mounting bracket may be used with flow substrates having component ports situated in different positions (e.g., asymmetric port placement versus symmetric port placement), different numbers of component conduit ports, different numbers of fluid handling component positions, and different numbers of manifold connection conduit ports in an interchangeable manner. These and other aspects of the present invention are now described in detail with respect to  FIGS. 2-11  below. 
       FIG. 2A  illustrates a cross-sectional view and an isometric view of a standardized fluid delivery stick in accordance with one embodiment of the present invention. As depicted in  FIG. 2A , the standardized fluid delivery stick  200 A includes a plurality of fluid handling components  60 X (i.e.,  601 ,  602 ,  603 ,  604 ), mounted to a plurality of modular surface mount flow substrates  300 , which are in turn mounted to a standardized fluid delivery stick bracket  500 . The plurality of fluid handling components may include nearly any two-port fluid handling component selected from among valves (manual, pneumatic, etc.), pressure sensors, pressure transducers, pressure regulators, filters, mass flow controllers (not shown), etc. As depicted, each of the plurality of fluid handling components is mounted to respective flow substrates  300  by a plurality of threaded component mounting fasteners  621   a ,  621   b ,  621   c ,  621   d  ( 621   c  and  621   d  are not visible in  FIG. 2A ) that pass through apertures in a base  610  of the respective fluid handling component  60 X and are received in threaded component mounting apertures (not visible in  FIG. 2A ) formed in a component attachment surface of the respective flow substrates. The flow substrates themselves are mounted to the standardized fluid delivery stick bracket  500  from below by a plurality of threaded flow substrate mounting fasteners  521  that pass through flow substrate mounting apertures in the standardized fluid delivery stick bracket  500  and are received in threaded flow substrate mounting apertures in a connection attachment surface of the respective flow substrates. In the embodiment depicted in  FIG. 2A , the standardized fluid delivery stick bracket  500  includes aligned flow substrate mounting apertures as described further in detail with respect to  FIG. 11B . The standardized fluid delivery stick  200 A passes fluid in a longitudinal direction from the stick inlet  201  to a stick outlet  202 . 
     In accordance with an aspect of the present invention, the standardized fluid delivery stick  200 A includes a modular manifold  400 A that mounts to a connection attachment surface of a flow substrate and is specifically adapted to route fluid in a transverse direction (defined herein as a direction substantially orthogonal to the longitudinal direction in a plane that is parallel to the component attachment surface of the flow substrates). In the embodiment depicted in  FIG. 2A , in addition to being able to route fluid in a transverse direction, the modular manifold  400 A is also capable of routing fluid in the longitudinal direction where the longitudinal flow path is physically located between adjacent standardized fluid delivery sticks in an area that, in typical fluid delivery panels, is free from other obstructions. This first type of modular manifold (termed type A or series A) which is capable of additionally routing fluid in a longitudinal direction in a region between adjacent fluid delivery sticks is referenced  400 A in  FIG. 2A  and in  FIG. 3A , and is referenced  400 A′ in  FIG. 9A  (where the use of the prime symbol indicates the manifolds are adapted for fluid handling components having symmetric port placement rather than asymmetric port placement as described further below). In the illustration of  FIG. 2A , manifold connection conduit port  380  is visible in the isometric view of the standardized fluid delivery stick  200 A. 
       FIG. 2B  illustrates an isometric view of a standardized fluid delivery stick in accordance with another embodiment of the present invention. The standardized fluid delivery stick  200 B depicted in  FIG. 2B  is functionally identical to the standardized fluid delivery stick  200 A described above with respect to  FIG. 2A , in all but one respect; for this reason, the reference numerals used in  FIG. 2A  correspond identically to those used in  FIG. 2A , with one exception. In contrast to the first type of manifold  400 A of  FIG. 2A , a second type of modular manifold  400 B is used instead. Like the first type of modular manifold  400 A, the second type of manifold  400 B mounts to a connection attachment surface of a flow substrate and is specifically adapted to route fluid in a transverse direction (i.e., substantially orthogonal to the longitudinal direction defined between the inlet  201  and the outlet  202  of the stick in a plane that is parallel to the component attachment surface of the flow substrates). Further, like the first type of manifold  400 A, the second type of manifold  400 B is also capable of routing fluid in a longitudinal direction that is generally parallel to the longitudinal direction defined between the inlet  201  and the outlet  202  of the stick. However, in contrast to the first type of manifold  400 A in which the longitudinal flow path is physically located between adjacent standardized fluid delivery sticks, the longitudinal flow path provided by the second type of manifold  400 B is physically located below the standardized fluid delivery stick bracket  500 . For this reason, the longitudinal path may extend from the inlet  201  to the outlet  202  of the fluid delivery stick and beyond, without any interference with the mounting feet  560  of the standardized fluid delivery stick bracket  500 . 
       FIG. 3A  illustrates a collection of modular flow substrates and modular manifolds in accordance with a first embodiment of the present invention for use with fluid handling components having asymmetric port placement (e.g., C-seal components) in which one of the ports of the fluid handling component is axially aligned with the center of the component and the other is situated off axis. (See, for example, the cross-sectional (i.e., upper) drawing in  FIG. 2A  in which each of the fluid handling components  60 X has such an asymmetric port placement). As details of the various modular flow substrates and modular manifolds depicted in  FIG. 3A  are described more fully in detail with respect to other figures below, only a general description of  FIG. 3A  is provided herein. 
     The top row of  FIG. 3A  illustrates plan and elevation views of various flow substrates  300 A in which the component conduit ports  320   a ,  320   b ,  320   c  formed in the component attachment surface  305  are arranged to fluidly communicate with fluid handling components having asymmetric port placement. A representative elevation view is shown in  FIG. 3A  immediately below the fourth example flow substrate plan view. Also formed in component attachment surface  305  are component mounting apertures  310   a ,  310   b  that are used to receive a threaded fastener ( 621   a ,  621   b  in  FIGS. 2A and 2B ) that mount a fluid handling component  60 X in sealing engagement with component conduit ports  320  of the flow substrate. 
     As illustrated, the flow substrate  300 A may include a tube stub connection  335  that would typically be fluidly connected (for example, by welding) to a source or sink of process fluid, and which would typically form either the first or last flow substrate  300 A in a fluid delivery stick. Shown in dotted line form are fluid pathways  375   a ,  375   b  that are formed within the body of the flow substrate and may be used to fluidly connect a first component conduit port  320   a  to a second component conduit port  320   b , to connect a tube stub connection  335  to a first component conduit port  320   a , to connect a component conduit port  320   a  to a manifold connection conduit port  380  (shown in dotted line form to indicate it is disposed on the surface opposing the component attachment surface  305 ). Also visible in dotted line form are the substrate mounting apertures  330   a ,  330   b  which are also disposed on the surface of the flow substrate opposing the component attachment surface  305 . 
     The second row of  FIG. 3A  illustrates a variety of modular manifolds of the first type  400 A that mount to a connection attachment surface of a flow substrate, that route fluid in a transverse direction, and that, in addition to being able to route fluid in a transverse direction, may also be capable of routing fluid in a longitudinal direction, where the longitudinal flow path is physically located between adjacent standardized fluid delivery sticks. A representative elevation view is shown in  FIG. 3A  immediately below the first example modular manifold plan view. Shown in  FIG. 3A  are the one or more tube stub connections  435   a ,  435   b ,  435   c , etc., the manifold conduit port  420 , and the fluid pathway  475  of the manifold. The manifolds  400 A may be fluidly connected to one another, for example, by welding, with or without intervening structures (e.g., straight lengths of tubing) to form nearly any fluid routing path. 
     The third row of  FIG. 3A  illustrates a variety of modular manifolds of the second type  400 B that mount to a connection attachment surface of a flow substrate, that route fluid in a transverse direction, and that, in addition to being able to route fluid in a transverse direction, may also be capable of routing fluid in a longitudinal direction, where the longitudinal flow path is physically located below the standardized fluid delivery stick bracket  500 . A representative elevation view is shown in  FIG. 3A  immediately below the first example modular manifold plan view. Shown in  FIG. 3A  are the one or more tube stub connections  435   a ,  435   b ,  435   c , etc., the manifold port  420 , and the fluid pathway  475  of the manifold. A plurality of threaded mounting apertures  410   a  and  410   b  are formed to receive a threaded fastener that extends through a flow substrate from above and pull the manifold into sealing engagement with the connection attachment surface of the substrate. The manifolds  400 B may be fluidly connected to one another, for example, by welding, with or without intervening structures (e.g., straight lengths of tubing) to form nearly any fluid routing path. 
       FIG. 3B  illustrates plan and elevation views of a variety of different flow substrates  300 A in accordance with the embodiment of  FIG. 3A  for use at higher fluid flow rates. It should be appreciated that unlike K1s substrates, flow substrates in accordance with the present invention may include multiple distinct fluid pathways  375 , such as illustrated, for example, with respect to the top-right substrate in  FIG. 3B . Details of each of the various flow substrates  300 A of  FIG. 3B  will be clear from the description of an exemplary flow substrate selected from  FIG. 3B  and described below with respect to  FIG. 4  in which exploded plan and cross-sectional views are illustrated. 
       FIG. 4  illustrates exploded plan and cross-sectional views of an exemplary flow substrate  300 A in accordance with an embodiment of the present invention. The flow substrate  300 A may be formed from a suitable solid block of material such as stainless steel, or where the application permits, from aluminum or brass. Where ionic contamination is a concern, polymer materials may be used, and the flow substrate may be formed from other than a solid block of material (e.g., by molding). 
     Formed in a component attachment surface  305  of the flow substrate are one or more component conduit ports  320 . Component conduit port  320   a  would typically be fluidly connected to the port (inlet or outlet) of a first fluid handling component, while component conduit port  320   b  would typically be fluidly connected to the port (outlet or inlet) of a second fluid handling component that is distinct form the first fluid handling component. Component conduit ports  320   b  and  320   c  would typically be connected to the same fluid handling component and illustrate how the substrate  300 A is specifically suited to fluid handling components having asymmetric port placement. Associated with component conduit port  320   a  is a pair of internally threaded component mounting apertures  310   a ,  310   b , each of which would receive the threaded end of a fastener, such as fasteners  621  (in  FIGS. 2A and 2B ). Typically, each fluid handling component is attached to one or more flow substrates by four fasteners, as shown with respect to component conduit ports  320   b  and  320   c  and their associated component mounting apertures  310   c ,  310   d ,  310   e , and  310   f  which would be used to mount a single fluid handling component in sealing engagement with component conduit ports  320   b  and  320   c.    
     Associated with each pair of component conduit ports is a leak port  325   a  (for component conduit ports  320   b  and  320   c ), and  325   b  (for component conduit port  320   d  and the component conduit port of an adjacent flow substrate). Also visible on the component attachment surface  305  is a through hole  326  that extends between a leak port associated with manifold connection conduit port  380  and the component attachment surface  305  of the flow substrate, so that a faulty seal between a manifold and a flow substrate may be detected from above. 
     The flow substrate  300 A includes a number of fluid pathways  375   a ,  375   b ,  375   c  that extend between conduit ports. For example, fluid pathway  375   a  extends between component conduit ports  320   a  and  320   b , fluid pathway  375   b  extends between component conduit ports  320   c  and  320   d , and fluid pathway  375   c  extends between component conduit port  320   c  and manifold connection conduit port  380  formed in connection attachment surface  315 . 
     A plurality of dowel pin apertures  350   a  and  350   b  are formed that extend from the component attachment surface  305  through to the connection attachment surface  315 . Each of these dowel pin apertures  350   a  and  350   b  can receive a dowel pin (not shown) and are used for backward compatibility with existing K1s systems, and may be omitted where backwards compatibility is not an issue. 
     A plurality of counter-bored manifold mounting apertures  390   a  and  390   b  are formed in the component attachment surface  305  of the flow substrate and extend through to the connection attachment surface  315 . Each of these apertures receives a threaded fastener that extends through the flow substrate and is received in a threaded mounting aperture  410  of a respective manifold  400 . The manifold conduit port  420  of the manifold  400  is pulled into sealing engagement with the manifold connection conduit port  380  of the flow substrate. It should be appreciated that in an alternative embodiment, the manifold mounting apertures  390   a ,  390   b  need not be counter-bored, but may instead use a fastener with a head sized suitably larger than the diameter of the aperture. 
     As can be seen in  FIG. 4 , component conduit ports  320 , manifold connection conduit ports  380  and fluid pathways  375  are all machined in a cost-effective manner in which each has its corresponding axis of symmetry normal to the plane of the face of the flow substrate that is respectively pierced. Thus, as visible in  FIG. 4 , component conduit ports  320   a ,  320   b ,  320   c , and  320   d  are formed by machining from the component attachment surface  305  into body of the flow substrate, manifold connection conduit port  380  is formed by machining from the connection attachment surface  315  into the body of the flow substrate, and fluid pathways  375   a ,  375   b , and  375   c  are respectively formed by machining into the body of the flow substrate from the top surface illustrated in Section A-A, the bottom surface illustrated in Section A-A, and the right hand surface illustrated in Section B-B. After machining, each of the fluid pathways is sealed with an end cap  385  that is welded in place to form a fluid tight seal. Visible in dashed line form in  FIG. 4  are a pair of flow substrate mounting apertures  330   a  and  330   b  that are offset from one another and may be used with the standardized fluid delivery stick bracket  500 A depicted in  FIG. 11A . Each of these mounting apertures is formed in the connection attachment surface  315  of the flow substrate and is internally threaded to receive a fastener  521  ( FIGS. 2A and 2B ) that mounts the flow substrate to the fluid delivery stick bracket  500 A. 
     As shown in  FIG. 4 , the region  399  (shown in dashed lines) of the flow substrate  300 A that interfaces with the manifold extends beyond other portions of the flow substrate, such that the fasteners that fasten fluid handling components to the flow substrate and the fasteners that fasten the manifold to the flow substrate  300 A are all accessible from a single direction, and without any interference from other structures. Although the embodiment  300 A of  FIG. 4  shows only a portion  399  of the flow substrate extends beyond other portions, the present invention is not so limited. For example,  FIG. 3A  illustrates another flow substrate  300 A (top row, third from the right) that includes a manifold connection conduit port  380  in which a width dimension of the flow substrate is uniformly greater than those flow substrates depicted in the same row. 
       FIG. 5  illustrates a collection of modular flow substrates in accordance with the first embodiment depicted in  FIG. 3A  for use at higher fluid flow rates and specifically adapted to be positioned at the beginning or end of a standardized fluid delivery stick. Each of these modular flow substrates includes a tube stub  335  suited for this purpose. 
       FIGS. 6A and 6B  illustrate plan and elevation views of a variety of different flow substrates in accordance with the embodiment of  FIGS. 3A and 3B , but for use at lower fluid flow rates. Like flow substrates  300 A depicted in  FIGS. 3A and 3B , each of the flow substrates depicted in  FIGS. 6A and 6B  is adapted for use with fluid handling components having asymmetric port placement. However, because these flow substrates are specifically adapted for lower flow rates by virtue of having a smaller diameter (0.09 inch rather than 0.18 inch) bore, each of these flow substrates is designated by the reference numeral  300 B. All other aspects of flow substrates  300 B are identical to those described previously with respect to flow substrates  300 A, and thus only differences will be described in detail herein with respect to  FIG. 7 , in which like reference numerals correspond to the same features described previously with respect to  FIGS. 3A ,  3 B,  4 , and  5 . It should be appreciated that although  FIGS. 6A and 6B  show a number of different flow substrates  300 B specifically adapted for use at lower flow rates, not all of the possible porting arrangements are illustrated. In this regard, it should be appreciated that the same variations in porting arrangements shown with respect to flow substrates  300 A in  FIGS. 3A and 3B  may be provided with respect to the flow substrates  300 B. The manifolds used with flow substrate  300 B may be the same as those described previously with respect to manifolds  400 A and  400 B of  FIG. 3A . 
     As can be seen in  FIG. 7 , component conduit ports  320  and manifold connection conduit ports  380  of low flow substrate  300 B are again machined in a cost-effective manner in which each has its corresponding axis of symmetry normal to the plane of the face of the flow substrate that is respectively pierced. Thus, as visible in  FIG. 7 , component conduit ports  320   a ,  320   b ,  320   c , and  320   d  are formed by machining from the component attachment surface  305  into the body of the flow substrate, and manifold connection conduit port  380  is formed by machining from the connection attachment surface  315  into the body of the flow substrate. Fluid pathways  375   a  and  375   b  are formed by machining from component attachment surface  315 , while fluid pathway  375   c  is formed by machining from the right hand surface illustrated in Section B-B. After machining, each of the fluid pathways  375   a  and  375   b  is sealed with a respective pathway cap  395   a  and  395   b  that is welded in place to form a fluid tight seal, and fluid pathway  375   c  is sealed with an end cap  385  that is welded in place to form a fluid tight seal. In one embodiment, the cap  395  may be formed from a sheet of stainless steel by laser cutting, by water jet cutting, or other suitable techniques. In other embodiments, other materials such as brass or aluminum may be used, and where ionic contamination is a concern and the flow substrate is formed from a polymer material, the cap  395  may be formed, for example, by molding a polymeric material that can later be epoxied into place. 
     Again visible in dashed line form in  FIG. 7  are a pair of flow substrate mounting apertures  330   a  and  330   b  that are offset from one another and may be used with the standardized fluid delivery stick bracket  500 A depicted in  FIG. 11A . Each of these mounting apertures is formed in the connection attachment surface  315  of the flow substrate and is internally threaded to receive a fastener  521  ( FIGS. 2A and 2B ) that mounts the flow substrate to the fluid delivery stick bracket  500 A. 
     As shown in  FIG. 7 , the region  399  (shown in dashed lines) of the flow substrate  300 B that interfaces with the manifold extends beyond other portions of the flow substrate, such that the fasteners that fasten fluid handling components to the flow substrate and the fasteners that fasten the manifold to the flow substrate  300 B are all accessible from a single direction, and without any interference from other structures. It should be appreciated that like the example of  FIG. 3A  (i.e., the flow substrate depicted in the top row, third from the right and shown as including a manifold connection port  380 ), the width dimension of those flow substrates  300 B that include one or more manifold connection conduit ports  380  could be uniform, albeit greater than those flow substrates  300 B that do not include any manifold connection conduit ports  380 . 
       FIG. 8A  illustrates plan and cross-sectional views of an exemplary alternative design flow substrate for use at lower fluid flow rates, in which the fluid pathway associated with the manifold connection conduit port has an increased diameter useful for pump/purge applications.  FIG. 8B  illustrates an isometric cut-away view of the exemplary flow substrate of  FIG. 8A . Although only one specific embodiment of a flow substrate is depicted in the various views shown in  FIGS. 8A-8B , it should be appreciated that other flow substrates may make use of a larger, higher flow component conduit ports, manifold connection conduit ports and fluid pathways in combination with other lower flow conduit ports and fluid pathways. 
     Like flow substrates  300 A, and  300 B described above, the flow substrate depicted in  FIGS. 8A-8B  is adapted for use with fluid handling components having asymmetric port placement. However, the flow substrate depicted in  FIGS. 8A-8B  is specifically adapted for lower flow rates by virtue of having a smaller diameter (0.09 inch rather than 0.18 inch) bore in the main fluid pathway  375   a , in combination with a larger diameter (0.18 inch) fluid pathway  375   c  and manifold connection conduit port  380  for use in pump and purge operations. Accordingly, this flow substrate is designated by the reference numeral  300 C. Other aspects of flow substrates  300 C are similar or identical in function to those described previously with respect to flow substrates  300 A and  300 B, and thus only the salient differences will be described in detail herein with respect to  FIGS. 8A-8B , in which like reference numerals correspond to the same or similar features described previously with respect to  FIGS. 4 and 7 . 
     As can be seen in  FIG. 8A , component conduit ports  320  and manifold connection conduit ports  380  of substrate  300 C are again machined in a cost-effective manner in which each has its corresponding axis of symmetry normal to the plane of the face of the flow substrate that is respectively pierced. Thus, as visible in  FIG. 8A , component conduit ports  320   a ,  320   b ,  320   c , and  320   d  are formed by machining from the component attachment surface  305  into the body of the flow substrate, and manifold connection conduit port  380  is formed by machining from the connection attachment surface  315  into the body of the flow substrate. However, the diameter of component conduit port  320   d  (0.18 inch) is double that of component conduit ports  320   a - c , as is the diameter of manifold connection conduit port  380 . 
     Due to its length and diameter, fluid pathway  375   a  is formed by machining from component attachment surface  315  into the body of the flow substrate, while fluid pathway  375   c  is formed by machining from the right hand surface illustrated in Section B-B. After machining, fluid pathway  375   a  is sealed with a pathway cap  395  that is welded in place to form a fluid tight seal, and fluid pathway  375   c  is sealed with an end cap  385  that is welded in place to form a fluid tight seal in a manner described previously. 
     Again visible in dashed line form in  FIG. 8A  are a pair of flow substrate mounting apertures  330   a  and  330   b  that are offset from one another and may be used with the standardized fluid delivery stick bracket  500 A depicted in  FIG. 11A . Each of these mounting apertures is formed in the connection attachment surface  315  of the flow substrate  300 C and is internally threaded to receive a fastener  521  ( FIGS. 2A and 2B ) that mounts the flow substrate to the fluid delivery stick bracket  500 A. 
     As shown in  FIG. 8A , the region  399  (shown in dashed lines) of the flow substrate  300 C that interfaces with the manifold extends beyond other portions of the flow substrate, such that the fasteners that fasten fluid handling components to the flow substrate and the fasteners that fasten the manifold to the flow substrate  300 C are all accessible from a single direction, and without any interference from other structures. 
       FIGS. 9A and 9B  illustrate a limited collection of modular flow substrates and modular manifolds in accordance with a second embodiment of the present invention that is specifically adapted for use with fluid handling components having symmetric port placement (e.g., W-Seal™ components), such as the fluid handling component  602 ′ depicted in  FIG. 9A . The top right portion of  FIG. 9A  illustrates the manner in which a fluid handling component  602 ′ may be attached to a flow substrate of this second embodiment, with the dashed lines showing which apertures in the base  610 ′ of the fluid handling component are aligned with corresponding component mounting apertures in the component attachment surface  305  of the flow substrate. 
     In general, the modular flow substrates and the modular manifolds of this second embodiment are structurally and functionally similar to those of the first embodiment. For example, the flow substrates in accordance with this second embodiment may include flow substrates having tube stub connections  335 , one or a plurality of component conduit ports  320  and/or manifold connection conduit ports  380 , a plurality of component mounting apertures  310 , a plurality of flow substrate mounting apertures  330 , a plurality of manifold mounting apertures  390 , etc. in a manner similar to flow substrates  300 A,  300 B, and  300 C described previously. Because the main difference between the flow substrates  300 A described previously relates to the symmetric (rather than asymmetric) placement of the component conduit ports  320  and the particular manner in which the component conduit ports are adapted to receive a particular type of seal (e.g., a W-Seal™ rather than a C-seal or other type of seal or gasket), this collection of flow substrates is designated by reference numeral  300 A.′ 
     Similarly, the modular manifolds of this second embodiment are structurally and functionally similar to those of the first embodiment and may include manifolds specifically adapted to additionally route fluid in a longitudinal direction where the longitudinal flow path is physically located between adjacent standardized fluid delivery sticks, designated by reference numeral  400 A′ in a manner analogous to manifolds  400 A described previously, or to additionally route fluid in a longitudinal direction, where the longitudinal flow path is physically located below the standardized fluid delivery stick bracket  500 , designated by reference numeral  400 B′ in a manner analogous to manifolds  400 B. Although not specifically illustrated in  FIGS. 9A and 9B , the flow substrates of this second embodiment may also be adapted to accommodate low flow applications in a manner analogous to flow substrates  300 B described previously, or low flow applications with a higher flow pump/purge ability in a manner analogous to flow substrates  300 C, also described previously. 
     Indeed, it should be appreciated that although  FIGS. 9A and 9B  show a number of different flow substrates  300 A′ and manifolds  400 A′ and  400 B,′ only a limited number of the possible porting arrangements are illustrated. In this regard, it should be appreciated that the same variations in porting arrangements shown with respect to the flow substrates  300 A and the manifolds  400 A and  400 B in  FIGS. 3A and 3B  may be provided with respect to the flow substrates  300 A′ and the manifolds  400 A′ and  400 B′. Because the main distinction between the flow substrates and manifolds of this second embodiment relate primarily to the symmetric (rather than asymmetric) placement of the component conduit ports  320  and the particular manner in which the component conduit ports are adapted to receive a particular type of seal (e.g., a W-Seal™), only the differences are described in detail herein. 
     Depicted in  FIG. 9A  are two new structures  900  and  901  that are unique to this second embodiment, but which may be adapted for use with flow substrates of the first embodiment in a straight-forward manner. For example, a cap  900  may be used to provide a passive fluid connection between adjacent component conduit ports  320  of a flow substrate where a fluid handling component is not desired. This cap  900  may be mounted to adjacent component conduit ports in the same manner as a fluid handling component, such that as depicted in the lower-right portion of  FIG. 9A , the cap  900  would simply replace the fluid handling component  602 ′. As can be seen in  FIG. 9A , the cap  900  may include a through hole  926  that extends between a leak port associated with a component conduit port  320  of the substrate  300 A′ so that a faulty seal between a cap and the flow substrate  300 A′ may be detected from above. An alternative cap structure  901  may be provided that is similar to cap  900 , but which includes a tube stub connection  935  that permits additional fluid routing. 
     Shown in  FIG. 10  is an alternative arrangement of the flow substrate mounting apertures  330   a  and  330   b  that may be used with the standardized fluid delivery stick bracket  500 B depicted in  FIG. 11B . Each of these mounting apertures  330   a ,  330   b  is formed in the connection attachment surface  315  of the flow substrate  300 A′ and is internally threaded to receive a fastener  521  ( FIGS. 2A and 2B ) that mounts the flow substrate to the fluid delivery stick bracket  500 B. This alternative arrangement of mounting apertures  330  may be incorporated into any to of the flow substrates described previously, and advantageously permits the flow substrates to be mounted to the fluid delivery stick bracket  500 B in one of two orientations, that differ from one another by a rotation of 180 degrees. 
       FIGS. 11A and 11B  illustrate two different standardized fluid delivery stick brackets in accordance with the present invention, in which the standardized fluid delivery stick bracket  500 A depicted in  FIG. 11A  uses offset flow substrate mounting apertures  530 , and in which the standardized fluid delivery stick bracket  500 B depicted in  FIG. 11B  uses aligned flow substrate mounting apertures  530 . The standardized fluid delivery stick bracket  500 B is depicted in  FIGS. 2A and 2B . 
     Each of the standardized fluid delivery stick brackets  500 A and  500 B secure the standardized fluid delivery stick  200 A,  200 B ( FIGS. 2A and 2B ) to a fluid delivery panel backplane (not shown) and thereby hold adjacent standardized sticks in correct transverse alignment to enable connection between bottom located flow substrate transverse manifold connection conduit ports and corresponding ports in the underlying transverse oriented manifold(s). The standardized fluid delivery stick bracket  500 A,  500 B is preferably unitary and can be formed of folded heavy gage sheet metal, extruded or die cast aluminum, or similar suitable structural design. 
     As shown in  FIGS. 11A and 11B , the fluid delivery stick bracket  500 A,  500 B includes a pair of U-shaped channels  540  that are dimensioned to receive a standard cartridge heater (not shown) for heating the flow substrates  300  that are mounted to the bracket  500 A,  500 B, and thereby, the process fluid flowing in the fluid delivery stick. As noted previously, fasteners  521  inserted from below and received in substrate mounting apertures  330  are used to mount the flow substrates  300  to the bracket  500 A,  500 B. Dowel pin apertures  550  to receive a dowel pin (not shown) are provided to help align the substrates with the apertures  530  in the bracket. The bracket  500 A,  500 B is itself mounted to the fluid delivery backplane by fasteners inserted through bracket mounting apertures  520  formed in mounting feet  560  of the bracket. The mounting feet  560  elevate the fluid delivery stick  200  above a top surface of the fluid delivery panel backplane to allow attachment of the manifolds  400  and to promote air circulation. 
     The fluid delivery stick bracket  500 A, and specifically the arrangement of the substrate mounting apertures  530  and the dowel pin apertures  550  is specifically adapted for backwards compatibility with the K1s system. The arrangement of the substrate mounting apertures  530  and the dowel pin apertures  550  of the fluid delivery stick  500 B permit compatible flow substrates  300  to be mounted to the fluid delivery stick bracket  500 B in one of two orientations, where one orientation is rotated by 180 degrees relative to an axis normal to the substrate mounting surface  501  of the fluid delivery stick bracket  500 B relative to the other. The spacing of the substrate mounting apertures  530  and the dowel pin apertures  550  of brackets  500 A and  500 B permit flow substrates of different length (viewed in a longitudinal direction from inlet to outlet of the stick) and having a varying number of component conduit ports formed in component attachment surface thereof to be placed adjacent to one another, as desired, while still registering with the flow substrate mounting apertures  330  and flow substrate dowel pin apertures  350  of the selected flow substrate. It should be appreciated that the spacing and number of mounting apertures  530  and the dowel pin apertures  550 , and the spacing and number of substrate mounting apertures  330  and dowel pin apertures  350  may be varied to allow compatible flow substrates to be mounted to the fluid delivery stick bracket  500  in multiple orientations, or to be compatible with existing systems, or both. 
     As should be appreciated from the foregoing description, embodiments of Applicant&#39;s invention provide a fluid delivery panel design in which individual fluid delivery sticks may be removed as a single unit by access from only a single direction simply by removing fasteners associated with the transverse manifolds and the fasteners securing the mounting feet  560  of the respective bracket  500 , each of which is accessible without the need to remove any other elements of the fluid delivery panel. 
     Embodiments of Applicant&#39;s invention provide a modular fluid delivery system where each flow substrate is built from port connection combinations containing one or more of (i) a MFC connection conduit port, (ii) an underside transverse manifold connection conduit port (when present), (iii) a central fluid handling component conduit port, or (iv) an edge component conduit port, or (v) an entire fluid handling component mounting location, where a specific collection of these flow substrates secured to a specific standardized fluid delivery stick bracket provides the fluid flow path for the specific standard fluid delivery stick fluid handling function, and where the transverse manifold connection conduit port is positioned off to the side (where there is usually an air circulation gap intentionally placed between fluid delivery sticks). 
     Although embodiments of the present invention have been described primarily with respect to the use of fluid handling components having two ports, it should be appreciated that embodiment of Applicant&#39;s invention could be modified for use with a three-port component, such as a 3-port valve. However, because such fluid handling components are less common, and typically more expensive, two-port fluid handling components are generally preferred. 
     Having thus described several aspects of at least one embodiment of this invention, it is to be appreciated various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to be part of this disclosure, and are intended to be within the scope of the invention. Accordingly, the foregoing description and drawings are by way of example only.