Abstract:
An abatement system is provided, including an abatement unit adapted to abate effluent using ambient air; and an ambient air delivery system in fluid communication with the abatement unit and adapted to deliver ambient air to the abatement unit; wherein the ambient air delivery system allows sufficient ambient air to flow into the abatement unit to abate the effluent without compressed air. Numerous other aspects are provided.

Description:
[0001]    The present application claims priority to U.S. Provisional Patent Application Ser. No. 60/988,770, filed Nov. 16, 2007 and entitled “METHODS AND APPARATUS FOR USING AMBIENT AIR DURING ABATEMENT OF SEMICONDUCTOR DEVICE MANUFACTURING EFFLUENTS” (Attorney Docket No. 12779/L2), which is hereby incorporated herein by reference in its entirety for all purposes. 
         [0002]    The present application is also a continuation-in-part of and claims priority to U.S. patent application Ser. No. 12/053,480, filed Mar. 21, 2008 and entitled “APPARATUS AND METHODS FOR AMBIENT AIR ABATEMENT OF ELECTRONIC DEVICE MANUFACTURING EFFLUENT” (Attorney Docket No. 12779), which claims priority to U.S. Provisional Application Ser. Nos. 60/973,977, filed Sep. 20, 2007 and 60/988,770, filed Nov. 16, 2007, all of which are hereby incorporated herein by reference in their entirety for all purposes. 
     
    
     FIELD OF THE INVENTION 
       [0003]    The present invention relates to electronic device manufacturing, and more specifically to hazardous and/or undesirable compound abatement systems which use ambient air as an oxidant. 
       BACKGROUND OF THE INVENTION 
       [0004]    Conventional electronic device manufacturing effluent abatement systems typically use clean dry air (“CDA”) as an oxidant. CDA, as the name implies, may be air which has been dried and highly filtered, and there is a cost associated with the preparation of CDA. In an electronic device manufacturing facility, CDA is typically supplied throughout the facility at a relatively high pressure, which can be about 90 psi, more or less. For use in a particular electronic device manufacturing facility system, such as an abatement system, the pressure of the facility CDA may then be reduced to a pressure required by the particular system. Pressurization of CDA requires equipment and energy. Reduction of CDA pressure requires at least equipment. 
         [0005]    Accordingly, methods and apparatus for reducing the costs associated with the use of CDA in an abatement unit are desirable. 
       SUMMARY OF THE INVENTION 
       [0006]    In some aspects, an abatement system is provided, including an abatement unit adapted to abate effluent using ambient air; and an ambient air delivery system in fluid communication with the abatement unit and adapted to deliver ambient air to the abatement unit; wherein the ambient air delivery system allows sufficient ambient air to flow into the abatement unit to abate the effluent without compressed air. 
         [0007]    In some aspects a method for abating effluent is provided, including providing effluent to an abatement unit; and providing ambient air to the abatement unit using an ambient air delivery system that allows sufficient ambient air to flow into the abatement unit to abate the effluent without compressed air. 
         [0008]    Other features and aspects of the present invention will become more fully apparent from the following detailed description, the appended claims and the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  is a schematic depiction of an abatement system according to the present invention. 
           [0010]      FIG. 2  is a schematic depiction of a second embodiment of an abatement system according to the present invention. 
           [0011]      FIG. 3  is a schematic depiction of an ambient air delivery system according to the present invention. 
           [0012]      FIG. 4  is a schematic depiction of an alternative embodiment of an ambient air delivery system according to the present invention. 
           [0013]      FIGS. 5A and 5B  are cross section side views of air amplifiers useful in the ambient air delivery systems of the present invention. 
           [0014]      FIG. 6  is a flow chart depicting a method of operating an abatement unit according to the present invention. 
           [0015]      FIG. 7  is a perspective view of a chamber distribution assembly according to the present invention. 
           [0016]      FIG. 8  is a cross section side view of a chamber distribution assembly according to the present invention. 
           [0017]      FIG. 9  depicts a bottom view of a chamber distribution assembly according to the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0018]    Electronic device manufacturing processes use a variety of reagents, and some reagents may pass through process tools unused. These unused reagents, if they are simply routed through a facility exhaust system, may be harmful to the environment, or pose a fire or explosion risk. In addition, electronic device manufacturing processes may create byproducts which pose similar harm or risks. For ease of reference, harmful, toxic, flammable and/or explosive, unused-reagents and byproducts may be referred to herein as ‘undesirable effluent’ or merely ‘effluent’. 
         [0019]    To avoid harm to the environment, and risk to employees and the public, the electronic device manufacturing industry has embraced the abatement of undesirable effluent. Abatement of undesirable effluent may take many forms, but ultimately abatement transforms undesirable effluent into non- or less harmful or risky materials. One method of abating undesirable effluent is to oxidize the effluent in an abatement reactor or unit using an oxidant such as oxygen. A ready source of oxidant which has been used for abatement units is CDA, which may usually be obtained from a facility CDA source. 
         [0020]    Because of its expense, however, the use of CDA is being budgeted or limited in many facilities. For example, some facilities may only budget or allow a conventional abatement system to use about 360 standard liters per minute (slm) of CDA. Some conventional abatement systems, however, may require 1000 slm or more of CDA to abate effluent. For example, processes for the manufacture of solar panels may exhaust large amounts of unused hydrogen and silane reagents. These large volumes of flammable and/or explosive gases require large volumes of oxidant to abate. Thus, the conventional abatement system may not comply with the CDA budget requirements of some facilities and therefore may not be selected by the customer. 
         [0021]    As described above, facility CDA is routed through the facility under pressure, typically at a pressure high enough to satisfy the needs of a facility system which has the highest pressure requirement of all of the facility systems. This pressure may be about 90 psi, more or less. For use in all other facility systems, including abatement systems (which may use up to about 45% to 80% percent of all of the CDA produced in a facility), the pressure of the CDA need not be so high. Pressurizing CDA for transport unnecessarily raises the cost of operating the abatement unit, because the abatement unit does not need air at such a high pressure. Similarly, drying the CDA for use in an abatement unit, where oxidant is not required to be dry, unnecessarily raises the cost of operation. It is thus desirable to operate abatement units while avoiding the costs associated with drying, highly filtering and compressing air. 
         [0022]    In some embodiments, the present invention may reduce or avoid the use of CDA by providing ambient air to abatement units through an ambient air delivery system. Ambient air may be obtained inside the room which houses the abatement unit, or from another space within the facility. Other sources of suitable ambient air may be employed such as air from outside the plant, or recycled facility air, for instance. Ambient air may be drawn into an abatement unit by a differential in pressure between the abatement unit reaction chamber (e.g., about −5 inches of water) and ambient air (e.g., about 0 inches of water). A blower or similar air moving device may be connected to an ambient air supply to move more air into the abatement unit reaction chamber than would be drawn into the abatement unit reaction chamber by the pressure differential alone. Air moving devices are not compressors which may be used to create air with a pressure which is greater than ambient pressure (e.g., about 0 inches of water) 
         [0023]    In some embodiments of the present invention, air may be supplied to an abatement unit by a naturally aspirated air system (NAAS) or the like. A NAAS is a system which allows the abatement unit to draw ambient air into the abatement unit, but which does not actively move the air. The NAAS may include an inlet that is open to ambient air, which is at about atmospheric pressure, and an outlet that may be coupled to the abatement system (and/or subsystems of the abatement system). In these embodiments, the abatement system may be operated at a pressure below atmospheric pressure. For example, the pressure inside the reactor may be about −1.2″ to −5″ of water (or another suitable pressure) relative to atmospheric pressure. In such a case, the air may naturally be drawn into the abatement system and/or subsystems by the pressure differential between the ambient air and the gas inside the abatement unit. In this manner, oxygen may be supplied to the reactor from the ambient air. Ambient air may be at other pressures, including below and above atmospheric pressure. For a NAAS to be effective, the pressure differential should be large enough such that air is drawn into the abatement unit at a rate which provides enough oxygen to abate the effluent flowing through the abatement unit to a desired level of abatement. 
         [0024]    In other embodiments a NAAS may be unable to provide all of the air required to abate the effluent to a desired degree. One way to abate the effluent to a desired degree of abatement is to flow a minimum amount of air into the abatement unit. This minimum amount of air may be readily determined by evaluating the nature of the effluent to be abated, and the mass flow rate of the effluent to be abated. If the difference between the pressure of the ambient air and the operating pressure of the abatement unit is too small, not enough air will be drawn into the abatement unit to effectively abate the effluent. In such a case, more air must be pushed or pulled into the abatement unit. In these other embodiments the ambient air delivery system may incorporate an air moving device, such as an air blower or amplifier, to push and/or pull sufficient air into the abatement system and/or its subsystems. 
         [0025]    In yet other embodiments, despite the fact that a sufficient pressure differential may exist between the ambient air and the abatement unit (i.e., sufficient to draw enough air into the abatement unit to effectively abate the effluent), the ambient air delivery system may still incorporate an air moving device, such as an air blower or amplifier, to push and/or pull air into the abatement unit. Incorporating such an air moving device into the ambient air delivery system may alleviate any temporary shortages of ambient air which may be caused by a temporary change in the operating pressure of the abatement unit or the pressure of the ambient air. 
         [0026]      FIG. 1  is a schematic diagram of an exemplary ambient air abatement system  100  of the present invention. The abatement system  100  may include an abatement unit  102  which may be adapted to abate effluent which has been exhausted from one or more process tools  104 . Effluent may flow from process tool  104  through conduit  106  to abatement unit  102 . Abatement unit  102  may be adapted to abate the effluent by reacting the effluent with oxygen. The oxygen may be provided to the abatement unit  102  as a component of ambient air which may be supplied to the abatement unit  102 , through conduit  107 , by ambient air delivery system  108 . Ambient air delivery system  108  may be connected through ambient air inlet  110  to ambient air source  112  from which ambient air delivery system  108  may draw ambient air. Although only one ambient air delivery system  108  is depicted, more than one, e.g., 2, 3, 4 or more, may be utilized. In some embodiments, abatement unit  102  may burn fuel in order to generate temperatures at which effluent will react with oxygen. Therefore, abatement unit  102  may be coupled to a fuel supply  114  through conduit  116 . The abated effluent may exhaust from abatement unit  102  through outlet  118 , from where it may pass to the atmosphere or to additional abatement devices, such as a point of use or house scrubber. 
         [0027]    The abatement unit  102  may be a reactor that is adapted to process the effluent. Such a reactor may be, for example, a fuel burning thermal abatement unit such as a Marathon Abatement System manufactured by Applied Materials, Inc. of Santa Clara, Calif. Alternatively, the abatement unit may be electrically heated, or heated by any suitable method. In some cases the abatement unit may not need to be heated in order to abate the effluent, such as when the effluent is itself flammable. 
         [0028]    The process tool  104  may be a system that includes process chambers (not shown) which produce the effluent that is abated by the abatement unit  102 . For example, the process tool  104  may be a deposition chamber or any other processing chamber which exhausts effluent which may be abated by abatement unit  102 . In a solar panel manufacturing facility, the process chambers may exhaust large quantities of hydrogen and/or silane. 
         [0029]    As discussed above, the ambient air delivery system  108  may supply ambient air to the abatement unit  102  from the ambient air source  112 . The structure and operation of ambient air delivery system  108  will be described in more detail below with reference to  FIGS. 3 and 4 . 
         [0030]    The ambient air source  112  may be ambient air that surrounds the abatement system  100 , although any suitable source of air may be employed. For example, the air may be ambient air that is filtered by HEPA filters commonly found in manufacturing facilities. Such air may or may not need to be filtered again prior to conveying the air to the abatement unit  102 . In such an embodiment, the ambient air delivery system  108  may be coupled to the frame of the ambient air abatement system  100  such that an inlet of the ambient air delivery system  108  is open to the ambient air surrounding the abatement system  100 . Alternatively, the ambient air source  112  may be air that is supplied from outside of the facility. In such an embodiment, the ambient air delivery system  108  may include a system of tubes or other conduits that are adapted to convey air from outside the facility to the abatement unit  102  in an amount sufficient to effectively abate the effluent. As used herein, it is to be understood that the term ‘air’ places no limitation on the temperature, pressure, composition, etc. of the gaseous compounds that are supplied by the ambient air source  112 . For example, it is to be understood that the term ‘air’ may include any composition of oxygen, nitrogen, etc. that is commonly found in the atmosphere, although any suitable source of gaseous compounds may be used. 
         [0031]    Fuel supply  114  may supply fuel alone or a fuel and air mixture to abatement unit  102 . The fuel may be hydrogen, methane, natural gas, methane or LPG, although any suitable fuel may be employed. The pressure of the fuel supplied to the abatement unit  102  may be about 0.2 psi to about 10 psi, although any suitable pressure may be employed. The fuel supply  114  may be coupled to the abatement unit  102  with, for example, stainless steel tubes adapted to convey fluids, although any suitable means of conveying the fuel may be employed. It is to be understood that embodiments provided in accordance with the present invention may not necessarily be coupled to the fuel supply  114 . For example, the abatement unit  102  may be a fuel-less reactor (e.g., where the effluent is flammable and only needs an ignition source and a source of air). 
         [0032]    In some embodiments, the abatement unit  102 , and/or any portions of the ambient air abatement system  100  (excluding the fuel supply  114 ), may be operated at a pressure that is lower than the pressure of the ambient air source  112 , creating a pressure differential or delta. It should be noted that although process tool  104  appears in  FIG. 1 , it does not form a part of the abatement system  100 . This pressure differential may cause ambient air to flow naturally through ambient air delivery system  108  into abatement unit  102 . If the pressure differential is large enough, sufficient ambient air may be drawn through the ambient air delivery system  108  and into the abatement unit  102 . The operation of the ambient air delivery system  108  will be discussed in more detail below. 
         [0033]    In other embodiments, the abatement unit  102 , and/or any portions of the abatement system  100 , may be operated at a pressure that is too high to create a pressure differential which would move sufficient air from the ambient air source  112  through the ambient air delivery system  108  into the abatement unit  102 , as described above. In such embodiments, the ambient air delivery system  108  may include an air moving device such as an air blower or an air amplifier, as discussed in more detail below with reference to  FIGS. 4 and 5 . 
         [0034]    In still further embodiments, the abatement unit  102  may be operated at a pressure that is lower than the pressure of the ambient air in the ambient air source  112 , and yet an insufficient amount of air may be move from the ambient air source  112  through the ambient air delivery system  108  and into abatement unit  102 . This may be due to the nature and volume of the effluent flowing through the abatement unit  102 . In such cases, the ambient air delivery system  108  may also include an air moving device such as an air blower or an air amplifier. 
         [0035]    In yet further embodiments, although the abatement unit  102  may be operated at a pressure that is sufficiently lower, on average, than the pressure of the ambient air source  112  to move sufficient ambient air through the ambient air delivery system  108  into the abatement unit  102 , there may be fluctuations in the operating pressure of the abatement unit  102  which cause temporary insufficient flows of air into the abatement unit  102 . This may result in unacceptable amounts of unabated effluent exiting the abatement unit  102 . In these embodiments, the ambient air delivery system  108  may also include an air moving device such as an air blower or an air amplifier, to even out the flow of air into the abatement unit  102 . 
         [0036]    Abatement system  200 , shown in  FIG. 2  is a an alternate embodiment of the abatement system  100  of  FIG. 1 . Reference numbers in  FIGS. 1 and 2  correspond to each other for ease of reference. For example, the abatement unit in  FIG. 1  has the reference number  102 , and the abatement unit in  FIG. 2  has the reference number  202 . 
         [0037]    Ambient air abatement system  200  is similar to abatement system  100 , but has the following differences. The ambient air delivery system  208  of abatement system  200  is connected to abatement unit  202  through five conduits  207 , whereas the ambient air delivery system  108  of abatement system  100  is connected to abatement unit  102  through a single conduit  107 . Furthermore, ambient air abatement system  200  may include five ambient air inlets  220 . As depicted, ambient air abatement system  200  may include optional coupling features  222  and adapters  224  (e.g., reducers or increasers) which are described in more detail below. Although conduits  207  are depicted as connecting to the abatement unit  202  through the adapters  224 , coupling features  222 , and the five ambient air inlets  220 , it is to be understood that the conduits  207  may be connected directly to the ambient air inlets  220  without the coupling features  222  and adapters  224 . Although five conduits  207  and ambient air inlets  220  are shown, fewer or more than five conduits  207  and ambient air inlets  220  may be used. The placement of air inlets on opposite sides, or symmetrically around, an abatement unit, as shown in  FIG. 2 , may result in a more uniform combustion zone within the abatement unit  202 . 
         [0038]    As described above, ambient air abatement system  200  may include ambient air inlets  220  which incorporate coupling features  222 . Coupling features  222  may enable one or more adapters  224  to be coupled to one or more ambient air inlets  220 . Coupling features  222  may be welds, threads, or any other coupling device suitable to couple an adapter  224  to the ambient air inlet  220 , etc. Adapters  224  may allow a conduit  207  having an inner diameter which is the same as, greater than, or smaller than, the inner diameter of the ambient air inlet  220  to be connected to the ambient air inlet  220 . It is to be understood that coupling features  222  may be combined with adapter  224  in a unitary device such as a coupling adapter. 
         [0039]    In addition, abatement system  200  is depicted as having three separate ambient air delivery systems  208 , and three separate ambient air sources  212 , compared to the single ambient air delivery system  108  and the single ambient air source of abatement system  100 . It should be noted that any desired number of ambient air delivery systems  208  and ambient air sources  212  may be employed in the practice of the present invention. Thus, there may be n air inlets  220 , which may be supplied with ambient air by n or fewer than n ambient air delivery systems  208 . Conversely, n air inlets  220  may be supplied with ambient air by more than n ambient air delivery systems  208 . An inlet  220  may be a tubular fitting to which an ambient air conduit  207  may be connected to supply ambient air to the abatement unit  202 . 
         [0040]    By sufficiently reducing resistance to airflow, the use of uncompressed ambient air (with or without the assistance of an air moving device) to abate effluent may be enabled. Thus, by reducing a number of bends in the air inlet  220  (e.g., a straight inlet), by polishing the interior surface of the inlet, and/or by increasing the inner diameter and/or number of inlets used to effectively increase a combined inlet cross-section, resistance to airflow may be reduced sufficiently to use ambient air. For example, an abatement system designed to use CDA (which may be supplied at a pressure of about 90 psi) may employ an air inlet  220  having an inner diameter of about ⅜″. On the other hand, an abatement system which employs one or more air inlets  220  having a larger inner diameter, e.g., between about 0.5 and about 1.5 inches, between about 0.7 and about 1.2 inches or about 1 inch, more or less, may be able to use ambient air and avoid a need to compress air. 
         [0041]    A minimum inner diameter of an air inlet  220  may be calculated based upon some or all of: an operating pressure (e.g., a maximum operating pressure) within the abatement unit  202 , a pressure (e.g., a minimum pressure) of the ambient air provided to the air inlet  220 , a flow rate (e.g., a maximum flow rate) of effluent into the abatement unit  202  and a desired residence time (e.g., minimum residence time) within the reactor. It should be noted that although an inlet  220  diameter may be selected to accommodate a maximum air flow which may be required when the abatement unit  202  is operating at a maximum capacity, less than a maximum air flow may be flowed through the inlets  220  when less than the maximum air flow is necessary. 
         [0042]    In another embodiment, the inlets  220  may be adapted to be connected, or removably connected, to conduits  207  which may have an inner diameter which is the same as or different from the inner diameter of the inlet  220 . For example, a size adapter, reducer or increaser may be welded onto an end of the inlet  220  which is opposite the abatement reactor  202 . Alternatively, the inlet  220  may be threaded so that an adapter, reducer or increaser may be threaded onto the inlet  220 . An abatement unit which is designed with the larger inlets  220  of the present invention for use with ambient air (with or without an air moving device) may also be used with pressurized air or CDA systems which utilize smaller diameter supply conduits. 
         [0043]    In one embodiment, a method for abating effluent is provided which includes the steps of providing effluent to an abatement unit and providing ambient air from an ambient air source to the abatement unit through an inlet which is adapted to provide low flow resistance to the ambient air. This method may use the inlets  220  described above. 
         [0044]    Each air inlet  220  may be the same size as each other air inlet  220  or a different size. In order to get the desired mass flow rates in such a case, the ambient air delivery system  208  may be designed, as discussed in more detail below, to provide individually selected mass flow rates of air to each air inlet  220 , or air at individually selected pressures to each air inlet  220 . 
         [0045]    In operation, abatement unit  202  may receive effluent through effluent inlets  226  at the top of the abatement unit  202 . Inside the abatement unit  202 , surrounding each effluent inlet  226 , there may be a plurality of burner jets (not shown). The burner jets may supply heat and flame directed in a downward direction in the abatement unit  202 , and the effluent may be abated, e.g., oxidized, as the effluent travels down through the abatement unit  202 . In some embodiments, abatement unit  202  may be designed such that it may be desirable to introduce air into the abatement unit  202  at a plurality of locations and at selected, different pressures or mass flow rates at one or more of the locations. For example, in some embodiments, it is desirable to conduct the oxidation reaction at the top of the abatement unit  202  in a fuel rich (i.e., oxygen poor) condition, to be followed, lower in the abatement unit  202 , with enough air to create an oxygen rich environment which may be sufficient to effectively abate the remaining unabated effluent. Such a design may help reduce the formation of nitrogen oxides and sulfur oxides. Providing different pressures or mass flow rates at individual air inlets  220  may be accomplished in any suitable fashion, as discussed below with reference to  FIGS. 3 and 4 . 
         [0046]    Ambient air delivery system  300 , depicted in  FIG. 3 , corresponds to the ambient air delivery system  108  and the ambient air delivery system  208  of  FIGS. 1 and 2 , respectively. 
         [0047]    Ambient air delivery system  300  may include air intake  302  which may draw ambient air from ambient air source  304 . Ambient air may pass through air intake  302 , through shut off valve  306  into airbox  308 . Ambient air may then pass from airbox  308  through conduit  310  and flow control valve  312  into manifold  314 . Manifold  314  may distribute ambient air through ambient air outlets  316  to conduits (not shown) which may transport ambient air to an abatement unit (not shown). Controller  318  may be any microcomputer, microprocessor, logic circuit, a combination of hardware and software, or the like, suitable to control the opening and closing of shut off valve  306  and flow control valve  312  through communications links  320  and  322 . 
         [0048]    Ambient air source  304  may be any suitable source of ambient air, as described above. Air intake  302  may be a 3 inch stainless steel or PVC vacuum tube, although any suitable conduit of any suitable shape may be used. 
         [0049]    Shut off valve  306  may be a gate valve or any valve which is suitable to open and close the ambient air path through air intake  302 . As depicted, the shut off valve  306  may be a solenoid or pneumatically actuated gate valve that may be provided by HVH, LLC, although any suitable valve may be employed. The shut off valve  306  may be adapted to open and close such that the air from the ambient air source  304  may be regulated. For example, it may be desired to completely close off the flow of air from the ambient air source  304  to the abatement system. Accordingly, the shut off valve  306  may close (e.g., extend a flat disc to close the air path) so as to prevent the air from being conveyed from the air intake  302  to the air box  308 . In this closed state air box  308  may be unable to convey any air from the ambient air source  304  to the abatement system. The shut off valve  306  may also be adapted to prevent effluent from flowing towards the ambient air source  304 . For example, the shut off valve  306  may be adapted to close when pressure in the abatement unit increases to an undesired pressure (e.g., atmosphere, a pressure greater than the ambient air pressure, etc.). 
         [0050]    Airbox  308  may be an air box, although any suitable containment vessel may be employed. As depicted, the air box  308  may provide a reservoir of air that may serve to dampen fluctuations in air pressure, improving the ability of the Ambient air delivery system  300  to control the flow of ambient air. Although the air box  308  is depicted in  FIG. 3 , it is possible that in some embodiments, the air box  308  may not be employed. Also, as depicted, the air box  308  is a rectangular box, although any suitable shape (e.g., cylindrical, hexagonal, etc.) shape may be employed. The size of airbox  308  may be selected based on factors such as the volume and velocity of ambient air designed to flow through the ambient air delivery system  300 . 
         [0051]    The flow control valve  312  may be a butterfly valve although any suitable valve may be employed. As depicted, the flow control valve  312  may be a solenoid or pneumatically actuated valve that may be controlled by controller  318 . The flow control valve  312  may have a flap in the body of the flow control valve  312  that rotates so as to increase or decrease the opening that the air being conveyed from the ambient air source  304  to the abatement system flows through. Thus, the air may be controlled to flow at a higher or lower rate (e.g., standard liters per minute) thereby regulating the flow from the ambient air source  304  to the abatement system. 
         [0052]    It should be noted that the functions of shut off valve  306  and flow control valve  312  may be performed by a single valve (not shown), such as a throttling gate valve or a metering shutoff valve. Such multifunction valves are expensive, however, and using one may be a more expensive way to provide these functions. 
         [0053]    The manifold  314  may be a box that is employed to distribute the air regulated by the flow control valve  312 . As depicted, the manifold  314  is a box with six ambient air outlets  316 . Although six ambient air outlets  316  are depicted in  FIG. 3 , more or fewer may be employed. Also, each ambient air outlet  316  may be coupled to one or more inlets (not shown) on the abatement system. Each ambient air outlet  316  may be sized independently of each other ambient air outlet  316  so that a selected amount of air may be flowed through the ambient air outlet  316  to a particular location in the abatement unit. 
         [0054]    In operation, the ambient air delivery system  300  embodiment may be useful, as discussed above, in abatement systems which are operated at pressures sufficiently below the pressure of the ambient air source  304  to create a sufficient pressure differential to move enough air through the Ambient air delivery system  300  into the abatement unit to effectively abate the effluent. In such a case, the pressure differential between the operational pressure of the abatement unit and the ambient air source  304  may cause sufficient air to flow through the ambient air delivery system  300  into the abatement unit. Flow control valve  312  may be used to select the overall amount of air which may be supplied through the ambient air delivery system  300  to the abatement unit. 
         [0055]    Ambient air delivery system  400 , shown in  FIG. 4 , is similar to the ambient air delivery system  300  shown in  FIG. 3 , with the following differences. Ambient air delivery system  400  may include an air moving device  424 , which may be an air blower, air amplifier, or any other suitable device for moving air. Controller  418  may control the rate at which air moving device  424  moves ambient air through the ambient air delivery system  400 . 
         [0056]    Air moving device  424  may be any air blower which can move a sufficient mass of air per unit time as may be required by a particular abatement scenario. For example, air moving device  424  may be a squirrel cage fan, a bladed fan, a turbo fan, or a roots blower, etc., although any suitable blower or fan may be used. 
         [0057]    In operation, ambient air delivery system  400  may be useful in abatement systems of the present invention which are operated at pressures which are too high, i.e., not sufficiently below the pressure of ambient air source  404 , to ensure that enough air will move through the ambient air delivery system  400  and into the abatement unit to effectively abate the effluent. In other embodiments, even if an abatement system is operated at pressures sufficiently below the pressure of the ambient air source  404  to passively move enough air through the ambient air delivery system  400  into the abatement unit to abate the effluent, air moving device  424  may be employed to ensure a constant flow of ambient air despite any pressure fluctuation which may occur in the operating pressure of the abatement unit. Such pressure fluctuation may occur due to fluctuations in the pressure of the house exhaust system which may be a motive force for pulling effluent through the abatement unit. 
         [0058]    With reference to  FIGS. 5A and 5B , air amplifier  500  may be an air amplifier, although any suitable means of pushing and/or pulling air from the ambient air source  512  to the abatement unit  502  may be employed. As depicted, the air amplifier  500  is cylindrical, although any suitable shape may be employed. The air amplifier  500  is depicted as including an inlet that is open to the source of air that is provided by the ambient air source  512 . The air amplifier  500  is also depicted as including an outlet that is open to the abatement unit  502 . The air amplifier  500  may be comprised of stainless steel, although any suitable material may be employed. 
         [0059]    The flow of air provided by the ambient air source  512  is indicated by a plurality of arrows  528  which are inside the air amplifier  500  and which point in a direction from the ambient air source  512  to the abatement unit  502 . The air amplifier  500  may be adapted to pull and/or push the air supplied by the ambient air source  512 . As depicted, the air supplied by the ambient air source  512  may be pulled through the air amplifier  500  by a supply of the CDA from the CDA source  530 . Although CDA is being employed in this embodiment of the ambient air delivery system of the present invention, the use of CDA is reduced because a relatively small amount of CDA is used to move a larger volume of air from the ambient air source  512 . 
         [0060]    A method of abating effluent  600  according to the present invention is provided in  FIG. 6 . The method begins in step  602  and proceeds to step  604  where an abatement unit adapted to abate effluent from an electronic device manufacturing process tool is provided. The method includes step  606  wherein an ambient air delivery system which comprises an air moving device is provided, and wherein the ambient air delivery system is adapted to provide ambient air to the abatement unit. Steps  604  and  606  may be performed in any order. The method also includes step  608  in which effluent is oxidized with the ambient air provided by the ambient air delivery system. The method ends in step  610 . 
         [0061]      FIG. 7  depicts a perspective view of a chamber distribution assembly  700  provided in accordance with the present invention. The chamber distribution assembly  700  may distribute air provided by an ambient air source into a combustion chamber. The chamber distribution assembly  700  may include a distribution plate  702  that is coupled to two air pipes  704   a - b  (although fewer or more air pipes may be used) which may be air inlets  220  as described above. The distribution plate  702  may also be coupled to a plurality of effluent inlet pipes  706   a - d.    
         [0062]    The distribution plate  702  may be an alloy steel plate although any suitable material may be employed. Although the distribution plate  702  is depicted as flat and circular in shape any suitable shape may be employed. The distribution plate  702  may couple the two air pipes  704   a - b  to the combustion chamber. 
         [0063]    The two air pipes  704   a - b  are stainless steel tubes that may be adapted to (e.g., wide enough) convey ambient air supplied by the ambient air source. The two air pipes  704   a - b  may be wide enough that the air supplied by the ambient air is conveyed at a desired volume (e.g., volumetric flow rate). The two air pipes  704   a - b  are depicted as a circular tube with a 90 degree bend although any suitable shape and/or orientation may be employed, such as straight, without a bend. 
         [0064]    In operation, the two air pipes  704   a - b  may convey air into the combustion chamber at ambient pressure as discussed in the preceding paragraphs. Additionally or alternatively, the air may be at a pressure that is higher (e.g., slightly) higher than the ambient pressure. A blower, air amplifier or any other suitable device as discussed in the preceding paragraphs may provide such higher pressures. 
         [0065]    Because the two air pipes  704   a - b  are suitably wide (e.g., about 1 inch in diameter) the air may be supplied to the combustion chamber with desirable parameters (e.g., pressure, flow rate, etc.). For example, air may be supplied at the ambient pressure from the ambient source while providing the volume of air necessary for the desired chemical reactions in the combustion chamber. Accordingly, effluent conveyed by the effluent inlet pipes  706   a - d  may be attenuated in a reaction that includes ambient as discussed in the preceding paragraphs. 
         [0066]      FIG. 8  depicts a cross section side view of the chamber distribution assembly  700  provided in accordance with the present invention. As depicted, the chamber distribution assembly  700  may include a diffusion plate  802  that is coupled to the distribution plate  702 . As depicted, the two air pipes  704   a - b  may terminate at the two air pipe exits  804   a - b.    
         [0067]    The diffusion plate  802  may be a porous ceramic although any suitable plate may be employed. As depicted, the diffusion plate  802  may traverse a portion of the chamber distribution assembly  700 . The diffusion plate  802  may be adapted to allow air to filter through the diffusion plate  802  into the combustion chamber. 
         [0068]    In operation, air supplied by the ambient air source may exit the two air pipes  704   a - b  at the two air pipe exits  804   a - b . The air may then flow through the diffusion plate  802  into the combustion chamber. That is, the diffusion plate  802  may allow the ambient air to filter through due to a pressure difference between the ambient air source and the internal region of the combustion chamber. Additionally or alternatively, the pressure difference may be between the exit of the blower (discussed in the preceding paragraphs) and the interior region of the combustion chamber. 
         [0069]      FIG. 9  depicts a bottom view of the chamber distribution assembly  700  provided in accordance with the present invention. As depicted, the chamber distribution assembly  700  may have two air deflectors  902   a - b  that are coupled to the distribution plate  702  via a plurality of deflector tabs  904   aa -bc. 
         [0070]    The air deflectors  902   a - b  may be a relatively thin piece of stainless steel although any suitable material may be employed. The air deflectors  902   a - b  are depicted as circular although any suitable shape may be employed. The air deflectors  902   a - b  may be disposed proximate to the distribution plate  702  by the plurality of deflector tabs  904   aa -bc. 
         [0071]    The plurality of deflector tabs  904   aa -bc may be bent stainless steel tabs although any suitable material and/or configuration may be employed. 
         [0072]    In operation, the air deflectors  902   a - b  may deflect air exiting the two air pipes  704   a - b  so as to diffuse the air. That is, air conveyed by the two air pipes  704   a - b  is deflected to move in a direction that is approximately parallel with the distribution plate  702 . 
         [0073]    The foregoing description discloses only exemplary embodiments of the invention. Modifications of the above disclosed apparatus and methods which fall within the scope of the invention will be readily apparent to those of ordinary skill in the art. 
         [0074]    Accordingly, while the present invention has been disclosed in connection with exemplary embodiments thereof, it should be understood that other embodiments may fall within the spirit and scope of the invention, as defined by the following claims.