Patent Publication Number: US-2020300392-A1

Title: Universal tube stub plug with seal port

Description:
FIELD OF THE DISCLOSURE 
     The present disclosure is directed to fluid delivery systems, and more particularly to extreme flow rate and/or high temperature surface mount fluid delivery systems for use in the semiconductor processing and petrochemical industries 
     BACKGROUND OF THE 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 that are specifically well suited for use in extreme flow rate and/or high temperature applications where the process fluid is to be heated to a temperature above ambient. 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. Nos. 5,803,507 and 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 system 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 or manifold to indicate fluid delivery system elements which contain passive fluid flow path(s) that may have other fluid handling devices mounted there upon. 
     An objective of the present disclosure is to provide a universal tube stub plug with seal port for fluid delivery substrates. Welded stubs can be prone to cracks and leaks due to external forces applied to the tube stub during installation and use. 
     Machining the tubes and/or tube stubs on the substrate and manifold is costly due to the large amount of material that needs to be removed in order to create the tube stub. Adding an external module bolted to the end of the substrate or manifold will increase its cost, length and complexity. 
     Additional information related to fluid delivery substrates can be found in U.S. Pat. No. 8,496,029 which is hereby incorporated by references as if fully set forth herein. 
     SUMMARY OF THE INVENTION 
     The present disclosure provides a solution to deficiencies in the design and implementation of flow control systems when tube stubs are welded to gas and fluid substrates. 
     The present disclosure enables the user to connect gas and fluid substrates and manifolds to other fluid substrates and manifolds with a stronger and cheaper connection. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIGS. 1A-E  show an exemplary manifold with a tube stub plug and a first anti-rotation feature, consistent with embodiments of the present disclosure. 
         FIGS. 2A-F  show an exemplary manifold with a tube stub plug and a second anti-rotation feature, consistent with embodiments of the present disclosure. 
         FIGS. 3A-C  show an exemplary manifold with a tube stub plug and a third anti-rotation feature, consistent with embodiments of the present disclosure. 
         FIGS. 4A-B  show a portion of an exemplary manifold with a tube stub plug that is not circular in shape, consistent with embodiments of the present disclosure. 
         FIGS. 5A-B  show an exemplary manifold with a tube stub plug with a stepped portion proximate the tube stub side of the manifold, consistent with embodiments of the present disclosure. 
         FIGS. 6A-B  show an exemplary manifold with a tube stub plug with a stepped portion proximate the seal surface side of the manifold, consistent with embodiments of the present disclosure. 
         FIGS. 7A-B  show an exemplary manifold with a tube stub plug with a stepped portion proximate the tube stub side of the manifold where the tube stub plug is secured to the manifold using a threaded connection, consistent with embodiments of the present disclosure. 
         FIGS. 8A-F  show exemplary tube stub plugs with a manifold, consistent with embodiments of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     The present disclosure uses a separate plug with stub at one end and seal at the other end. An opening through the substrate or manifold can receive the tube stub plug. The tube stub will enable the port to connect other manifolds or to process and deliver gases and fluids while also providing surface mount seal on the component mounting side. 
     Different material and configurations of the tube stub plug and receptacle locations on the substrate and manifold can depend on configuration, application and industry which these configurations are used. 
       FIGS. 1A-E  show an exemplary manifold and a tube stub plug assembly and a first anti-rotation feature, consistent with embodiments of the present disclosure. The first embodiment can include a manifold and tube stub plug assembly  100  with a manifold  102  with a tube stub plug hole  104  and a round tube stub plug  106  with tube stub  108  on the one end and seal surface  110  on other end. The tube stub plug hole  104  can be machined through the manifold  102  (see  FIG. 1B ). It should be noted that this arrangement can also be applied to holes/tube stubs in substrates (e.g., the term “substrate” can be substituted for “manifold” for anything described herein) that can be connected to the manifold  102  (not shown in  FIGS. 1A-E ). 
     An anti-rotation retainer threaded opening  112  can be machined on the top of the tube stub plug  106  to keep the position of the seal surface  110  of a seal port (as part of the manifold  102 ) to other seal ports (not shown in  FIGS. 1A-B ) on a manifold while also keeping the alignment to top surface. An anti-rotation pin  114  (see  FIG. 1E ) can be inserted into the anti-rotation retainer threaded opening  112   
     A positioning plate (not shown in  FIGS. 1A-E ) can be mounted to a seal side of a manifold (e.g., manifold  102 ) to secure the planarity and orientation (i.e., angle) of the tube stub plug (e.g., tube stub plug  106 ) to the other seal surfaces (i.e., the seal surface  110  and a corresponding seal surface on a substrate (not shown)). During construction, a fastener can be inserted through a hole in the positioning plate into a corresponding hole on the manifold to keep the tube stub plug against a fixture plate while also keeping the angular alignment of the tube stub plug and other seals (not shown) in a desired location and/or orientation while the tube stub plug is fixed to the manifold (e.g., welded, or secured in some other fashion). 
     The manifold (e.g., manifold  102 ) and the tube stub plug (e.g., tube stub plug  106 ) of the assembly  100  with tube stub plug exposed toward the welding process can be positioned for adding a weld  116  to add additional strength, and to further lock in the location and orientation of the tube stub plug, and seal the joint between the tube stub plug and the manifold (or a substrate (not shown)). The weld can either be a continuous weld (see, e.g., weld  116 A in  FIGS. 1D-E ; weld  216 A in  FIG. 2E ) around the entire interface of the manifold and the tube stub plug (at the surface of the manifold) or one or more tack welds (see, e.g., welds  216 B in  FIGS. 2A-D  and  2 F) at various locations at the interface. 
     After welding of the tube stub plug, the alignment fixture from the other side of the manifold (or substrate) can be removed. The weld process can include, for example, Ebeam, laser, manual welding and other standard industry used welding processes appropriate for the application. Benefits of this embodiment include increased strength of the tube by using the whole body of substrate and manifold to support the tube and/or the tube-substrate joint as pressure is applied to the tube (e.g., as forces are applied to a portion of the tube). This embodiment can also result in a lower cost than a separately mounted body to the end of the substrate or manifold. 
       FIGS. 2A-F  show an exemplary manifold and a tube stub plug assembly and a second anti-rotation feature, consistent with embodiments of the present disclosure. The second embodiment can include a manifold and tube stub plug assembly  200  with a manifold  202  with a tube stub plug hole  204  and a round tube stub plug  206  with tube stub  208  on the one end and seal surface  210  on other end. The tube stub plug hole  204  can be machined through the manifold  202 . Similar to embodiment 1, an anti-rotation hole  212  can be drilled through the tube stub plug body to keep the position of the seal port to other seal ports on the substrate and manifold. A fixture (not shown in  FIGS. 2A-F ) can be used to keep the seal surface aligned to the other seal surface on the substrate and manifold. It should be noted that this arrangement can also be applied to holes/tube stubs in substrates (e.g., the term “substrate” can be substituted for “manifold” for anything described herein) that can be connected to the manifold  202  (not shown in  FIGS. 2A-F ). In this embodiment, one or more countersunk holes  218  can be drilled (in  FIG. 2A  there are two) on the top of the tube stub plug  206  and the manifold  202 . The tube stub plug  206  can further be held in place by, for example, a tack weld  216  of the joint between the tube stub plug  206  and the substrate or manifold  202  inside of the countersunk holes  216 . The countersunk holes  218  can ensure that the weld beads of the weld  216  are not above a surface of the substrate or manifold  202  surface to prevent interference with mounting of components to the substrate surface of the manifold  202 . A fixture (i.e., a positioning plate; tacking fixture; not shown in  FIGS. 2A-F ) can be mounted to a seal side of the substrate and manifold (e.g., manifold  202 ) to secure the planarity and angle of the tube stub plug (e.g., the tube stub plug  206 ) to the other seal surfaces during assembly. A weld process can be used to further secure the tube stub plug with the substrate. The weld can either be a continuous weld (see, e.g., weld  216 A in  FIG. 2E ) around the entire interface of the manifold and the tube stub plug (at the surface of the manifold) or one or more tack welds (see, e.g., welds  216 B in  FIGS. 2A-D  and  2 F) at various locations at the interface. The weld process can include, for example, Ebeam, laser, manual welding and other standard industry used welding processes appropriate for the application of the substrate and manifold. 
       FIG. 2E  shows another version of the second embodiment of a tube stub plug coupled with the substrate. This embodiment can have an anti-rotation pin  214  as shown in  FIG. 2E  and the tube stub plug  206  can be welded to the manifold (e.g., a continuous weld joint  216 A shown in  FIG. 2E ). 
     Another variation of the second embodiment, shown in  FIG. 2F , can include the manifold and tube stub plug assembly  200  with the manifold  202  and the tube stub plug  206 . The manifold  200  can include the anti-rotation pin  214  to prevent rotation and two tack welds  216 B between the tube stub plug and the manifold. Other numbers of tack welds are possible (1, 3, 4, 5, 6, 7, etc.) depending on, for example, the size of the welds and the location of the welds. The manifold and the tube stub portion adjacent the manifold can each have a tack weld recessed portion that allows for the addition of the tack weld without adding material above the surface of the manifold (e.g., the seal surface side of the manifold). In other embodiments (not shown), the tack weld can be made without a tack weld recessed portion, allowing the tack weld to protrude above the manifold surface and the tube stub portion surface. 
     After tack welding of the tube stub plug at the countersunk holes  218 , the assembly  200  can removed from the tacking fixture (not shown in  FIGS. 2A-D ). Benefits of this embodiment can include increased strength for the tube stub by using the whole body of substrate and manifold as pressure (e.g., force) is applied to the tube; use of a tack weld reduces the requirement to for a more complicated final weld fixture; and lower cost than a separately mounted body to the end of the substrate or manifold. 
       FIGS. 3A-B  show an exemplary manifold with a tube stub plug and a third anti-rotation feature, consistent with embodiments of the present disclosure. The third embodiment can include a manifold and tube stub plug assembly  300  with a manifold  302  including a tube stub plug opening  304  and tube stub plug  306  with a tube stub  308  on the one end and a seal surface  310  on the other end. The shape of the tube stub plug  306  can any suitable shape including, for example, oval, triangular, square, rectangular, or hexagonal with or without rounded corners. The shape of the tube stub plug  306  can be determined on a given application, including, for example, space considerations. It should be noted that this arrangement can also be applied to holes/tube stubs in substrates (e.g., the term “substrate” can be substituted for “manifold” for anything described herein) that can be connected to the manifold  302  (not shown in  FIGS. 3A-C ).The tube stub plug  306  can have at least one fastener hole.  FIGS. 3B-C  show an example with two fastener holes) to allow the tube stub plug  306  to be secured into the substrate or manifold body by a fastener. 
     An opening  304  for tube stub plug  306  can be machined through the manifold  302  to enable it to receive the tube stub plug  306  configuration with at least one threaded hole to secure two parts to each other (e.g., the tub stub plug  306  to the manifold  302 ). In some applications and bolting configuration, no welding is required to secure the tube stub plug  306  with the manifold  302 . When needed/desired, a weld process as described herein (e.g., tack weld or continuous weld) can be used to further secure the tube stub plug  306  with the manifold  302 . The weld process can include, for example, Ebeam, laser, manual welding and other standard industry used welding processes appropriate for the application of the substrate and manifold. 
     Benefits of this embodiment can include that the body of the tube stub plug is used as a rotational alignment aid to other seals on the substrate or manifold; design that do not require welding; configurations and shapes of the tube stub plug can be changed to accommodate space available on the substrate or manifold; no welding or alignment fixture is needed for the instances where welding is needed/desired to secure the tube stub plug; the tube stub plug can more easily be replaced/changed to accommodate different tube lengths, and lower cost than a separately mounted body to the end of the substrate or manifold. 
       FIGS. 4A-B  show a portion of an exemplary manifold with a tube stub plug that is not circular in shape, consistent with embodiments of the present disclosure. The fourth embodiment can include a manifold and tube stub plug assembly  400  with a manifold  402  including a tube stub plug opening  404  and an oval tube stub plug  406  with tube stub  408  on the one end and a seal surface  410  on the other end. The shape of the tube stub plug  406  can be any suitable shape including, for example, oval, triangular, square, rectangular, or hexagonal with or without rounded corners. The shape of the tube stub plug  406  can be determined on a given application, including, for example, space considerations. It should be noted that this arrangement can also be applied to holes/tube stubs in substrates (e.g., the term “substrate” can be substituted for “manifold” for anything described herein) that can be connected to the manifold  402  (not shown in  FIGS. 4A-B ). An opening for tube stub plug  406  can be machined through the manifold to enable it to receive the tube stub plug  406  with at least one threaded hole to secure two parts to each other (e.g., the tub stub plug  406  to the manifold  402 ). A threaded hole can be machined on the seal side of the tube stub plug  406  body to keep a surface position of the seal port  410  to other seal ports on the manifold  402 . A fixture can used to keep the seal surface  410  aligned to the other seal surfaces on the manifold (e.g., to maintain planarity between the tube stub plug  406  and the manifold surface, to maintain a specific orientation of the tube stub plug  406 , etc.). When needed/desired, a weld process as described herein (e.g., tack weld or continuous weld) can be used to further secure the tube stub plug  406  with the manifold  402 . The weld process can include, for example, Ebeam, laser, manual welding and other standard industry used welding processes appropriate for the application of the substrate and manifold. 
     Benefits of this embodiment can include that the body of the tube stub plug is used as a rotational alignment aid to other seals on the substrate or manifold; the configuration and shape of the tube stub plug can be changed to accommodate space considerations on the substrate and/or manifold. 
       FIGS. 5A-B  show an exemplary manifold with a tube stub plug with a stepped portion for alignment of a seal surface on the tube stub plug and the manifold, consistent with embodiments of the present disclosure. The fifth embodiment can include a manifold and tube stub plug assembly  500  with a manifold  502  including a tube stub plug opening  504  and a round or oval tube stub plug  506  with tube stub  508  on the one end and seal surface  510  on other with a stepped portion on the tube side of the tube stub plug  506  (e.g., further from the surface of the manifold  502  proximate the seal surface  510 ). This configuration of the tube stub plug  506  requires insertion of the tube stub plug  506  from the top (i.e., the seal surface  510  side) of the manifold  502 . The shape of the tube stub plug can be any suitable shape including, for example, oval, triangular, square, rectangular, or hexagonal with or without rounded corners. The shape of the tube stub plug  506  can be determined on a given application, including, for example. space considerations. A round tube stub plug (not shown in  FIGS. 5A-B ; see, e.g.,  FIGS. 1A-E ) can be used provided that it includes an anti-rotation feature (e.g., an anti-rotation pin, tack weld(s), continuous weld, etc.) to align the angle/position of the seal port to other ports on manifold. It should be noted that this arrangement can also be applied to holes/tube stubs in substrates (e.g., the term “substrate” can be substituted for “manifold” for anything described herein) that can be connected to the manifold  502  (not shown in  FIGS. 5A-B ). 
     The opening  504  for tube stub plug  506  can be machined through the manifold, and the tube stub plug  506  can include a stepped portion  520  (i.e. shelf; step, etc.) at the bottom (tube stub  508 ) side of the tube stub plug  506 . The opening  504  can also include a step corresponding to that on the tube stub plug  506 . The step  520  can be any suitable configuration (e.g., a right angle as shown in  FIG. 5A ) to align a top surface of the tube stub plug with a surface of the substrate. Other examples include an angled surface (e.g., a wedge shape). The step  520  can be a portion of the tube stub plug  506  (e.g., ¼ or ½ of the tube stub plug  506 , etc.) or the step  520  can go all the way around the circumference of the tube stub plug  506 . A fixture can be used to keep the tube stub plug  506  in the manifold during welding of the tube stub plug to the manifold. The weld process can include, for example, Ebeam, laser, manual welding and other standard industry used welding processes appropriate for the application of the substrate and manifold. 
     Benefits of this embodiment can include that the body of the tube stub plug is used as a rotational alignment aid to other seals on the substrate or manifold; the weld fixture needed is simple; the configuration and shape of the tube stub plug can be changed to accommodate space considerations on the substrate and/or manifold; lower cost than a separately mounted body to the end of the substrate or manifold. 
       FIGS. 6A-B  show an exemplary manifold with a tube stub plug with a stepped portion proximate the seal surface side of the manifold, consistent with embodiments of the present disclosure. The sixth embodiment can include a manifold and tube stub plug assembly  600  with a manifold  602  including a tube stub plug opening  604  and a round or oval tube stub plug  606  with tube stub on the one end and seal surface on other with step on the tube side of the tube stub plug. The shape of the tube stub plug can any suitable shape including, for example, oval, triangular, square, rectangular, or hexagonal with or without rounded corners. The shape of the stub can be determined on a given application, including, for example, space considerations. A round tube stub plug can be used provided that it an anti-rotation feature (e.g., an anti-rotation pin, etc.) to align the angle of the seal port to other ports on the substrate or manifold. It should be noted that this arrangement can also be applied to holes/tube stubs in substrates (e.g., the term “substrate” can be substituted for “manifold” for anything described herein) that can be connected to the manifold  602  (not shown in  FIGS. 6A-B ). 
     Then opening  604  for tube stub plug can be machined through the substrate and manifold with step (i.e., a step; a shelf; a stepped portion) at the top (seal surface  610 ) side of the tube stub plug  606 . The tube stub  604  can have a corresponding step that matches the profile of the step in the opening  604 , which allows for alignment of the tube stub plug  606  for both depth (e.g., aligning seal surfaces) and rotational alignment (in the case of round tube stub plugs (see, e.g.,  FIGS. 1A-E ). Because the tube stub plug  606  is inserted into manifold  602  from the bottom (i.e., the side further from the seal surface  610  sides), there is no need for fixturing the tube stub plug  606  to the manifold during welding, as the step aligns the seal surface  610  with other seal surfaces on the manifold. The weld process can include, for example, Ebeam, laser, manual welding and other standard industry used welding processes appropriate for the application of the substrate and manifold. 
     Benefits of this embodiment can include that the body of the tube stub plug is used as a rotational alignment aid to other seals on the substrate or manifold; no weld fixture is needed to align the seal surfaces of the tube stub plug and the substrate; lower cost than a separately mounted body to the end of the substrate or manifold. 
       FIGS. 7A-B  show an exemplary manifold with a tube stub plug with a stepped portion proximate the tube stub side of the manifold where the tube stub plug is secured to the manifold using a threaded connection, consistent with embodiments of the present disclosure. The seventh embodiment can include a manifold and tube stub plug assembly  700  with a manifold  702  including a tube stub plug opening  704  and a round or oval tube stub plug  706  with tube stub  708  on the one end and seal surface  710  on the other end with step on the tube side of the tube stub plug and a corresponding step in the manifold  702 . The shape of the tube stub plug  706  can any suitable shape including, for example, oval, triangular, square, rectangular, or hexagonal with or without rounded corners. The shape of the tube stub plug  706  can be determined on a given application, including, for example, space considerations. A round tube stub plug can be used provided that it an anti-rotation feature (e.g., an anti-rotation pin, etc.) to align the angle of the seal port to other ports on the substrate or manifold. It should be noted that this arrangement can also be applied to holes/tube stubs in substrates (e.g., the term “substrate” can be substituted for “manifold” for anything described herein) that can be connected to the manifold  702  (not shown in  FIGS. 7A-B ). 
     The opening  704  for tube stub plug  706  can be machined through the manifold with step shelf at the bottom (tube stub  708 ) side of the tube stub plug  706 . The tube stub plug  706  can have a threaded portion (hidden from view in  FIGS. 7A-B ) on the tube stub  708  side which can allow a nut  722  to secure the tube stub plug  706  to the manifold. Since the step  720  can be designed to position the top seal surface of the tube stub plug  706  with other seal surfaces, the nut  722  pulls the two parts together and there is less need for welding the tube stub plug to the substrate. In some embodiments, it may still be desirable to add tack welds or a continuous weld. 
     Benefits of this embodiment can include that the body of the tube stub plug is used as a rotational alignment aid to other seals on the substrate or manifold; no welding required; the configuration and shape of the tube stub plug can be changed to accommodate space considerations on the substrate and/or manifold; lower cost than a separately mounted body to the end of the substrate or manifold. 
       FIGS. 8A-F  show exemplary tube stub plugs with a manifold, consistent with embodiments of the present disclosure. The eighth embodiment can include a manifold and tube stub plug assembly  800  with a manifold  802  including a tube stub plug opening  804  and a tube stub plug  806 A that is coupled with the opening  804  in the first surface  824  of the manifold where the tube stub  808  projects from the tube stub plug  806  at a right angle (i.e., a right angle tube stub, a side tube stub, a horizontal tube stub, etc.) from the first surface  824 . In this embodiment, the tube stub plug  806 A can be secured to the manifold using, for example, a welded joint  816 A (see section C-C of  FIG. 8A ).  FIG. 8B  shows additional views of the tube stub plug  806 A and the weld joint  816 A. It should be noted that this arrangement can also be applied to holes/tube stubs in substrates (e.g., the term “substrate” can be substituted for “manifold” for anything described herein) that can be connected to the manifold  802  (not shown in  FIGS. 8A-F ). 
     Other variations of the side tube stub are also possible.  FIG. 8C  shows different configurations of a side tube stub that can include, for example, a right angle side tube stub  806 A, an offset horizontal tube stub  806 B, and a straight horizontal tube stub  806 C. The different embodiments can allow for a tube stub to be placed with the tube stub projecting from the top (i.e., first surface  824 ), bottom (i.e., second surface; not shown in  FIGS. 8A-F ), or any side (i.e., a third surface, a fourth surface, etc.; not shown in  FIGS. 8A-F ) of a manifold or any combination of surfaces. 
     The tube stub can also be formed in a straight configuration designed for a bottom (or top) vertical mounting closer to the center of a substrate.  FIGS. 8D  shows an exemplary bottom tube stub  806 D for a bottom mount application (e.g., inserted into the manifold from the side opposite the seal surfaces.  FIG. 8E  shows cross-sectional views of the bottom mount tube stub  806 D coupled with the manifold  802 .  FIG. 8F  shows additional views of the bottom mount tube stub  806 D with an anti-rotation pin  814  and a weld joint  816 A securing the tube stub  806 D to the manifold. 
     The various tube stubs can address the many different flow path inlet and outlet configurations required in surface mount fluid delivery systems. The basic configurations would be horizontal or vertical inlets and outlets within the fluid flow paths. The various tube stubs can be used for top, bottom, or side inlets and outlets within the fluid flow paths. Any suitable material can be used for the tube stubs including, for example, stainless steel, heavy metal alloys, polymers, etc. The tube stubs can be coupled with the manifolds/substrates using any suitable attachment technique and/or fastener, including screws, bolts, locking/press pins, welding, adhesive, friction, etc. The different embodiments described herein can allow for any of the tube stub configurations to be placed with the tube stub projecting from the top (i.e., first surface), bottom (i.e., second surface), or any side (i.e., a third surface, a fourth surface, etc.) of a substrate or any combination of surfaces. 
     As shown and described herein and in the incorporated patents/application, a manifold or substrate body can be formed from a solid block of material and have an associated weld cap, each of which may be formed from a suitable material (such as stainless steel) in accordance with the intended use of the flow substrate. Primarily for cost reasons, but also for those applications that warrant the use of non-metallic materials (such as where ionic contamination is a concern), the body and/or weld cap of the manifold or flow substrate may also be formed (e.g., molded or machined) from polymeric materials, such as plastic. The use of other materials, such as plastic, permits the flow substrate to be particularly well suited to chemical delivery applications or biological applications where ionic contamination is a concern, and/or applications where cost is a concern. 
     The weld cap can be coupled with the manifold or substrate body using adhesive (i.e., glue) or similar mechanism (e.g., industrial metal bonding or non-metal bonding glue to create a bonded joint). The adhesive can be applied to the manifold or substrate body, the weld cap, or both using any application method (e.g., spraying, taping, dispensing, brush etc.). This configuration can be used for coupling metal, plastic, composite and other non-metal applications that are not conducive to welding. The adhesive can be selected to be resistant to the type of material flowing through the system to allow for a leak-free coupling (i.e., joint, connection, etc.). A benefit of using adhesive to couple the weld cap to the manifold or substrate body includes the ability to create a leak-free coupling that is resistant to the material flowing through the system without the time and cost associated with welding the weld cap to the manifold or substrate body. 
     It will be appreciated that details of the foregoing embodiments, given for purposes of illustration, are not to be construed as limiting the scope of the present disclosure. Although several embodiments of the present disclosure have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of the present disclosure. Accordingly, all such modifications are intended to be included within the scope of the present disclosure, which is further defined in the converted utility application and appended claims. Further, it is recognized that many embodiments may be conceived that do not achieve all the advantages of some embodiments, particularly preferred embodiments, yet the absence of a particular advantage shall not be construed to necessarily mean that such an embodiment is outside the scope of the present disclosure.