Abstract:
Apparatuses for preparing a surface of a substrate using a proximity head includes a carrier to hold and move the substrate along an axis and a proximity head having a head surface with a plurality of outlet ports defined thereon. The proximity head is defined to be positioned proximate and over the carrier and the surface of the substrate. A length of the head surface of the proximity head is defined to be greater than a diameter of the substrate and at least partially overlapping over the carrier when the substrate is present. The proximity head includes a first set of outlet ports in a first region defining a first applicator that is configured to apply a non-Newtonian fluid between a surface of the carrier and the head surface of the proximity head. A second set of outlet ports in a second region of the proximity head defines a second applicator that is configured to apply a first chemistry to the surface of the substrate when present. The second region is adjacent to the first region. A third set of outlet ports in a third region of the proximity head defines a third applicator that is configured to apply the non-Newtonian fluid between the head surface of the proximity head and the surface of the substrate when present. The third region is defined adjacent to the second region. A fourth set of outlet ports is defined in the second region of the proximity head to substantially remove the first chemistry from the surface of the substrate when present.

Description:
CLAIM OF PRIORITY 
       [0001]    This application is a divisional application of U.S. application Ser. No. 11/704,435 entitled “Method for Contained Chemical Surface Treatment” filed on Feb. 8, 2007, and incorporated herein by reference. 
       CROSS REFERENCE To RELATED APPLICATIONS 
       [0002]    This application is related to U.S. patent application Ser. No. 10/608,871, filed Jun. 27, 2003, and entitled “Method and Apparatus for Removing a Target Layer from a Substrate Using Reactive Gases”; U.S. patent application Ser. No. 10/746,114, filed on Dec. 23, 2003, and entitled “Method and Apparatus for Cleaning Semiconductor Wafers using Compressed and/or Pressurized Foams, Bubbles, and/or Liquids”; U.S. patent application Ser. No. 11/532,491, filed on Sep. 15, 2006, and entitled “Method and Material for cleaning a substrate”; U.S. patent application Ser. No. 11/532,493, filed on Sep. 15, 2006, and entitled “Apparatus and System for cleaning a substrate”. The disclosure of each of these related applications is incorporated herein by reference for all purposes. 
     
    
     FIELD OF THE INVENTION 
       [0003]    The present invention relates generally to semiconductor substrate processing, and more particularly, to systems and methods for a contained chemical surface treatment to remove particles from a surface of a semiconductor substrate during fabrication operations. 
       DESCRIPTION OF THE RELATED ART 
       [0004]    During a substrate manufacturing process, a surface of a substrate is continuously exposed to various chemicals. The chemicals used in the various manufacturing process operations may be a source for one or more contaminants that form on the surface of the substrate. These contaminants deposit on the surface of the substrate as particulates and may likely cause damage to the devices and features within the vicinity of the contaminant particles. It is, therefore, necessary to eliminate the contaminants from the surface of the substrate in a timely and efficient manner without damaging features and devices. 
         [0005]    Conventional substrate cleaning methods have relied on either mechanical force or chemicals to remove particulate contamination from the substrate surface. As devices and feature sizes continue to decrease in size and they become more fragile, the mechanical force applied in the cleaning methods increase the likelihood of causing damage to these features and devices. Using chemicals to remove contamination has proven another challenge The application and removal of the chemicals cause uncontrolled de-wetting (among other problems) that leads to creation of watermarks and other defects on the surface. In addition, the conventional cleaning methods have been unable to provide a substantially oxygen-free or low oxygen environment in a treatment region during the cleaning operation. The presence of oxygen in the treatment region during cleaning may cause oxidation of copper and other metals used in forming the features at the treatment region, such as interconnects, rendering the features and devices connected by these interconnects inoperable. Thus, efficient and non-damaging removal of contaminants during fabrication represents a continuing challenge. 
         [0006]    In view of the foregoing, a more effective and less abrasive cleaning technology is needed in removing the contaminants from the surface of the substrate. 
       SUMMARY 
       [0007]    The present invention fills the need by providing improved apparatuses for preparing a surface of a substrate using a proximity head. It should be appreciated that the present invention can be implemented in numerous ways, including apparatuses. Several inventive embodiments of the present invention are described below. 
         [0008]    In one embodiment, an apparatus for preparing a surface of a substrate using a proximity head is disclosed. The apparatus includes a carrier to hold and move the substrate along an axis. The apparatus also includes a proximity head having a head surface with a plurality of outlet ports defined thereon. The proximity head is defined to be positioned proximate and over the carrier and the surface of the substrate. A length of the head surface of the proximity head is defined to be greater than a diameter of the substrate and at least partially overlapping over the carrier when the substrate is present. The proximity head includes a first set of outlet ports in a first region. The first set of outlet ports defines a first applicator that is configured to apply a non-Newtonian fluid between a surface of the carrier and the head surface of the proximity head. A second set of outlet ports is defined in a second region of the proximity head. The second set of outlet ports defines a second applicator that is configured to apply a first chemistry to the surface of the substrate when present. The second region is adjacent to the first region. A third set of outlet ports is defined in a third region of the proximity head. The third set of outlet ports defines a third applicator that is configured to apply the non-Newtonian fluid between the head surface of the proximity head and the surface of the substrate when present. The third region is defined adjacent to the second region. A fourth set of outlet ports is defined in the second region of the proximity head to substantially remove the first chemistry from the surface of the substrate when present. 
         [0009]    In another embodiment, an apparatus for preparing a surface of a substrate using a proximity head is disclosed. The apparatus includes a carrier to hold and move the substrate along an axis. The apparatus also includes a proximity head having a head surface with a plurality of outlet ports defined thereon. The proximity head is defined to be positioned proximate and over the carrier and the surface of the substrate. A length of the head surface of the proximity head is defined to be greater than a diameter of the substrate and at least partially overlapping over the carrier when the substrate is present. The proximity head includes a first set of outlet ports in a first region. The first set of outlet ports defines a first applicator that is configured to apply a non-Newtonian fluid between a surface of the carrier and the head surface of the proximity head. A second set of outlet ports is defined in a second region of the proximity head. The second set of outlet ports defines a second applicator that is configured to apply a first chemistry to the surface of the substrate when present. The second region is adjacent to the first region. A third set of outlet ports is defined in a third region of the proximity head. The third set of outlet ports defines a third applicator that is configured to apply a second chemistry to the surface of the substrate when present. The third region is defined apart from the second region. A fourth set of outlet ports is defined in a fourth region of the proximity head. The fourth set of outlet ports defines a fourth applicator that is configured to apply the non-Newtonian fluid between the head surface of the proximity head and the surface of the substrate when present. The fourth region is defined in between the second and the third regions of the proximity head. A fifth set of outlet ports is defined in a fifth region of the proximity head defining a fifth applicator configured to apply the non-Newtonian fluid between the head surface of the proximity head and the surface of the substrate when present. The fifth region is defined adjacent to the third region. A sixth set of outlet ports is defined in the second region of the proximity head to substantially remove the first chemistry applied to the surface of the substrate when present. A seventh set of outlet ports is defined in the third region of the proximity head to substantially remove the second chemistry applied to the surface of the substrate when present. 
         [0010]    In yet another embodiment, an apparatus for preparing a surface of a substrate using a proximity head is disclosed. The apparatus includes a substrate supporting device to receive and hold the substrate along a plane and a proximity head having a plurality of outlet ports to supply a non-Newtonian fluid and a Newtonian fluid. The proximity head includes a first set of outlet ports defining a non-Newtonian fluid applicator to apply a non-Newtonian fluid between the surface of the substrate and a head surface of the proximity head. The applied non-Newtonian fluid defines a containment wall along one or more sides between the head surface and the surface of the substrate. The one or more sides provided with the non-Newtonian fluid defines a treatment region on the substrate between the head surface and the surface of the substrate. The proximity head further includes a second set of outlet ports defining a Newtonian fluid applicator to apply a Newtonian fluid to the surface of the substrate, such that the applied Newtonian fluid is substantially contained in the treatment region due to the defined containment wall. The Newtonian fluid aids in the removal of one or more contaminants from the surface of the substrate. The Newtonian fluid is immiscible in the non-Newtonian fluid. 
         [0011]    Other aspects and advantages of the invention will become more apparent from the following detailed description, taken in conjunction with the accompanying drawings, illustrating by way of example the present invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    The invention may best be understood by reference to the following description taken in conjunction with the accompanying drawings. These drawings should not be taken to limit the invention to the preferred embodiments, but are for explanation and understanding only. 
           [0013]      FIG. 1  is a simplified block diagram illustrating a proximity head applying a non-Newtonian fluid and a Newtonian fluid, in one embodiment of the invention. 
           [0014]      FIG. 2  illustrates a side schematic view of an alternate embodiment using proximity head to apply a non-Newtonian fluid and a Newtonian fluid to the surface of a substrate. 
           [0015]      FIG. 3A  is a schematic view illustrating a relative movement of the Newtonian fluid applied to the surface of a substrate, in one embodiment of the invention. 
           [0016]      FIG. 3B  is an alternative embodiment illustrated in  FIG. 3A . 
           [0017]      FIG. 3C  is an alternate embodiment illustrated in  FIGS. 3A and 3B . 
           [0018]      FIG. 3D  is an alternate embodiment illustrated in  FIG. 3C . 
           [0019]      FIG. 4  illustrates a simplified schematic diagram of a dual proximity head used in applying a non-Newtonian fluid and a Newtonian fluid to a surface of the substrate, in one embodiment of the invention. 
           [0020]      FIG. 5  illustrates a simplified schematic diagram of a proximity head used in applying a non-Newtonian fluid and two different types of Newtonian fluids to the surface of the substrate, in one embodiment of the invention. 
           [0021]      FIG. 6A  illustrates an application of a non-Newtonian fluid and two different types of Newtonian fluids to the surface of the substrate illustrated in  FIG. 5 , in one embodiment of the invention. 
           [0022]      FIG. 6B  is an alternate embodiment illustrated in  FIG. 6A . 
           [0023]      FIG. 6C  is an alternate embodiment illustrated in  FIGS. 6A and 6B . 
           [0024]      FIG. 7  illustrates various operations involved in providing a contained chemical surface treatment to a surface of a substrate, in one embodiment of the invention. 
           [0025]      FIG. 8A through 8D  is an alternative embodiment illustrated in  FIG. 3A , in one embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0026]    Several embodiments for effectively removing the contaminants from a surface of a substrate will now be described. It will be obvious, however, to one skilled in the art, that the present invention may be practiced without some or all of these specific details. In other instances, well known process operations have not been described in detail in order not to unnecessarily obscure the present invention. 
         [0027]    Effective removal of contaminants from the surface of a substrate is important to preserve the quality and functionality of the features formed on the substrate and the resulting semiconductor products, e.g., microchips. In one embodiment of the invention, the contaminants are removed by applying a Newtonian fluid, typically a cleaning chemistry, DI water, or mixtures of fluids to the surface of the substrate using a proximity head. As described herein, a Newtonian fluid is a fluid in which the viscosity depends on temperature and pressure (and chemical composition) and not on the shear stress acting upon it. A Newtonian fluid adheres to the definition of Newton&#39;s Law of viscosity. 
         [0028]    For additional information about Non-Newtonian and Newtonian fluids, reference can be made to U.S. application Ser. No. 11/174,080, filed on Jun. 30, 2005 and entitled “METHOD FOR REMOVING MATERIAL FROM SEMICONDUCTOR WAFER AND APPARATUS FOR PERFORMING THE SAME.” This patent application, which is assigned to Lam Research Corporation, the assignee of the subject application, is incorporated herein by reference. 
         [0029]    As described herein, a proximity head is a substrate treatment apparatus that can deliver precise volumes of a fluid to a surface of a substrate to be treated, and remove the fluid from the surface, when the proximity head is placed in close relation to the surface of the substrate. In one example, the proximity head has a head surface and the head surface is placed substantially parallel to the surface of the substrate. A meniscus is formed between the head surface and the surface of the substrate. The proximity head may also be configured to deliver a plurality of fluids and are configured with vacuum ports for removing the plurality of fluids that were delivered. 
         [0030]    A “meniscus”, as used herein, refers to a volume of chemistry bounded and contained in part by surface tension of the chemistry between the head surface of a proximity head and a surface of the substrate. The meniscus thus formed, may be moved over the surface in the contained shape and is used to remove the contaminants, particulates or unwanted materials from the surface of the substrate. Furthermore, the meniscus shape can be controlled by precision fluid delivery and removal systems that may further include a computing system. For more information on the formation of a meniscus and the application to the surface of a substrate, reference may be made to: (1) U.S. Pat. No. 6,616,772, issued on Sep. 9, 2003 and entitled “METHODS FOR WAFER PROXIMITY CLEANING AND DRYING,”; (2) U.S. patent application Ser. No. 10/330,843, filed on Dec. 24, 2002 and entitled “MENISCUS, VACUUM, IPA VAPOR, DRYING MANIFOLD,” (3) U.S. Pat. No. 6,988,327, issued on Jan. 24, 2005 and entitled “METHODS AND SYSTEMS FOR PROCESSING A SUBSTRATE USING A DYNAMIC LIQUID MENISCUS,” (4) U.S. Pat. No. 6,988,326, issued on Jan. 24, 2005 and entitled “PHOBIC BARRIER MENISCUS SEPARATION AND CONTAINMENT, ” and (5) U.S. Pat. No. 6,488,040, issued on Dec. 3, 2002 and entitled “CAPILLARY PROXIMITY HEADS FOR SINGLE WAFER CLEANING AND DRYING,” each is assigned to Lam Research Corporation, the assignee of the subject application, and each is incorporated herein by reference. 
         [0031]    By controlling the delivery and removal of the fluids to the meniscus, the meniscus can be controlled and moved over the surface of the substrate. In some embodiments, the substrate can be moved, while the proximity head is still, and in other embodiments, the proximity head moves and the substrate remains still, during the processing period. Further, for completeness, it should be understood that the processing can occur in any orientation, and as such, the meniscus can be applied to surfaces that are not horizontal (e.g., vertical substrates or substrates that are held at an angle). 
         [0032]    For additional information with respect to the proximity head, reference can be made to an exemplary proximity head, as described in the U.S. Pat. No. 6,616,772, issued on Sep. 9, 2003 and entitled “METHODS FOR WAFER PROXIMITY CLEANING AND DRYING.” This U.S. patent application, which is assigned to Lam Research Corporation, the assignee of the subject application, is incorporated herein by reference. 
         [0033]    For additional information about top and bottom menisci, reference can be made to the exemplary meniscus, as disclosed in U.S. patent application Ser. No. 10/330,843, filed on Dec. 24, 2002 and entitled “MENISCUS, VACUUM, IPA VAPOR, DRYING MANIFOLD.” This U.S. patent application, which is assigned to Lam Research Corporation, the assignee of the subject application, is incorporated herein by reference. 
         [0034]    In one embodiment, a proximity head is first used to apply a non-Newtonian fluid between the surface of the substrate and a head surface of the proximity head. 
         [0035]    As described herein, a non-Newtonian fluid is a fluid in which the viscosity changes with an applied shear stress. A non-Newtonian fluid does not obey Newton&#39;s Law of viscosity. The shear stress is a non-linear function of the shear rate. Depending on how the apparent viscosity changes with shear rate, the flow behavior of the non-Newtonian fluid will also change. An example of a non-Newtonian fluid is a soft condensed matter which occupies a middle ground between the extremes of a solid and a liquid. The soft condensed matter is easily deformable by external stresses. Examples of the soft condensed matter include emulsions, gels, colloids, foam, etc. As used herein, an emulsion is a mixture of immiscible liquids such as, for example, toothpaste, mayonnaise, oil in water, etc. 
         [0036]    For more information about non-Newtonian fluid, reference can be made to U.S. patent application Ser. No. 11/153,957, filed on Jun. 15, 2005, and entitled “METHOD AND APPARATUS FOR CLEANING A SUBSTRATE USING NON-NEWTONIAN FLUIDS”; and U.S. patent application Ser. No. 11/154,129, filed on Jun. 15, 2005, and entitled “METHOD AND APPARATUS FOR TRANSPORTING A SUBSTRATE USING NON-NEWTONIAN FLUID.” These patent applications, which are assigned to Lam Research Corporation, the assignee of the subject application, are incorporated herein by reference. 
         [0037]    The non-Newtonian fluid defines a containment wall (wall) along one or more sides between the head surface and the surface of the substrate. The one or more sides of the containment wall define a treatment region on the substrate. A meniscus of Newtonian fluid is then applied to the surface of the substrate through the proximity head, such that the applied Newtonian fluid is substantially contained in the treatment region defined by the containment wall. The Newtonian fluid includes chemistry that aids in substantial removal of contaminants from the surface of the substrate when the Newtonian fluid flows within the containment wall of the non-Newtonian fluid in the treatment region. 
         [0038]    The purpose of the containment wall formed by the non-Newtonian fluid is two-fold. First, the containment wall acts as a barrier or interface that substantially prevents the Newtonian fluid in the treatment region from flowing out, thereby conserving use of the Newtonian fluid. Additionally, some of these Newtonian fluids may have certain hazardous properties and so the Newtonian fluids have to be handled and disposed carefully. Utilizing the containment wall to control the Newtonian fluid, less amount of Newtonian fluid is expended while facilitating safe and efficient removal of contaminants from the surface of the substrate. Second, the containment wall acts as a barrier preventing any other external chemicals and contaminants from the ambient environment such as air, oxygen, nitrogen, etc. from flowing into the treatment region, so that highly concentrated and uncontaminated Newtonian fluids can be applied directly to the surface of the substrate. Controlled application of the Newtonian fluid provides for efficient and effective removal of contaminants from the surface of the substrate. The Newtonian fluid may be a chemistry that is substantially oxygen-free or a low oxygen chemistry that is applied to the surface of the substrate for removal of the contaminants. Utilizing non-Newtonian fluids to provide containment walls, a substantially oxygen-free or a low oxygen chemical treatment region can be achieved. 
         [0039]    In one embodiment, the presence of oxygen in the treatment region may result in the oxygen reacting with layers of the semiconductor substrate, resulting in increased dielectric constants, poor adhesion characteristics of subsequent layers, and other material changes to the properties of semiconductor materials used in the fabrication process. The oxygen-free or a low oxygen chemical treatment region prevents oxidation of metal features within the treatment region, thereby, enhancing the functionality of the features. 
         [0040]      FIG. 1  is a simplified schematic diagram of a proximity head  130  applying a non-Newtonian fluid and a meniscus of a Newtonian fluid to a surface  115  of a substrate  110  such that the Newtonian fluid is contained within one or more containment walls  140  of a non-Newtonian fluid. As shown, a substrate  110  is received on a carrier  120  using pins  122 , in one embodiment of the invention. The pins  122  extend from the carrier defining a recessed region in which the substrate  110  may be fully received and held. In one embodiment, the pins only contact an edge exclusion region  113  along the outer edge of the substrate  110 . The carrier  120  and the pin  122  are made of or coated with a chemically inert material, so that the carrier and the pins  122  do not react with the chemistries applied to clean or prepare the substrate  110 . A non-Newtonian fluid  101  is applied using a proximity head  130 . The non-Newtonian fluid  101  forms a containment wall  140  along one or more sides. The containment wall  140  defines a treatment region on the substrate  110 . In this embodiment, the non-Newtonian fluid  101  is formed along two opposite sides forming containment walls  140  along the two opposite sides enclosing a channel in-between. 
         [0041]    The enclosed channel, between the containment walls  140 , defines a treatment region. This treatment region may occupy either a portion of a surface  115  of a substrate  110  or the entire surface  115  of the substrate  110  when applied to the surface  115  of the substrate  110 . A Newtonian fluid  102  is then applied through the proximity head  130  such that the Newtonian fluid  102  is contained in the channel defining the treatment region formed by the non-Newtonian fluid  101 . The Newtonian fluid  102  contained within the treatment region may scan the surface  115  of the substrate  110  providing treatment of the entire surface  115  of the substrate  110  when applied to the surface  115  of the substrate  110 . The Newtonian fluid  102  aids in the removal of the contaminants from the surface  115  of the substrate  110  when the contaminants are exposed to the Newtonian fluid  102  contained in the treatment region. 
         [0042]      FIG. 2  illustrates a schematic representation of a single proximity head used in applying a non-Newtonian fluid  101  and a Newtonian fluid  102  to a surface  115  of a substrate  110 . As shown, a substrate  110  having an edge exclusion region  113 , is received on a pin  122  of a carrier  120 . A proximity head  130  is used in applying a meniscus of a non-Newtonian fluid  101  and a Newtonian fluid  102 . In this embodiment, the non-Newtonian fluid  101  is applied at about the edge exclusion region  113  through the proximity head  130  so that a containment wall  140  is formed along a portion of the edge of the substrate between the surface  115  of the substrate  110  and a head surface of the proximity head  130 . Although, in this embodiment, the non-Newtonian fluid  101  is applied at the edge exclusion region  113 , the non-Newtonian fluid (NNF)  101  is not confined to this region. The NNF  101  can be applied to any portion of the surface  115  of the substrate  110 . The containment wall  140  defines a treatment region  205  on the surface  115  of the substrate  110 . In this embodiment, the containment wall  140  is formed by a pair of walls  140  (or surrounded by walls) defining a channel for the treatment region  205 . A Newtonian fluid  102  is applied to the surface  115  of the substrate  110  through the proximity head  130 . 
         [0043]    The Newtonian fluid  102  is applied such that the Newtonian fluid  102  is contained within the treatment region  205  defined by the containment wall  140 . The channel enables the Newtonian fluid  102  to flow between the containment wall  140  formed by the non-Newtonian fluid  101 . The Newtonian fluid  102  flowing between the containment wall  140  aids in the removal of one or more contaminants while preserving the functionality of the features formed on the substrate  110 . The containment of the Newtonian fluid  102  within the containment wall  140  helps in expending less Newtonian fluid  102  while effectively removing contaminants from the surface  115  of the substrate  110 . 
         [0044]    The thickness of the containment wall  140  formed by the non-Newtonian fluid  101  can be varied based on one or more characteristics of the Newtonian fluid  102  applied to the surface of the substrate. Some of the characteristics of the Newtonian fluid  102  that may affect the thickness of the non-Newtonian fluid  101  may include viscosity, temperature, pressure exerted by the Newtonian fluid  102 , chemistry of the Newtonian fluid, etc. 
         [0045]    As noted above, the non-Newtonian fluid  101  is a fluid in which the viscosity changes with an applied shear force. An example of a non-Newtonian fluid  101  is a soft condensed matter which occupies a middle ground between the extremes of a solid and a liquid. The soft condensed matter is easily deformable by external stresses and examples of the soft condensed matter include emulsions, gels, colloids, foam, etc. It should be appreciated that an emulsion is a mixture of immiscible liquids such as, for example, toothpaste, mayonnaise, oil in water, etc. A colloid is polymers dispersed in water, and gelatin is an example of a colloid. Foam is gas bubbles defined in a liquid matrix, and shaving cream is an example of a foam. 
         [0046]    The non-Newtonian fluid  101  applied to the surface of the substrate is selected such that it is substantially immiscible with the Newtonian fluid  102 . The non-Newtonian fluid  101  may be a non-aqueous tri-state compound which includes a solid component, a liquid component and a gas component. The solid component is, in one embodiment, a fatty acid. The fatty acid is defined by one of lauric acid, palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, arachidonic acid, gadoleic acid, eurcic acid, butyric acid, caproic acid, caprylic acid, myristic acid, margaric acid, behenic acid, lignoseric acid, myristoleic acid, palmitoleic acid, nervanic acid, parinaric acid, timnodonic acid, brassic acid, clupanodonic acid, lignoceric acid, or cerotic acid. 
         [0047]    The gas component is defined to occupy 5% to 99.9% of the tri-state compound by volume. In another embodiment, the gas portion can occupy between about 15% and about 40% of the tri-state body, and still another embodiment, the gas portion can occupy between about 20% and about 30% of the tri-state body. The gas or gases defining a gas portion can be either inert, e.g., nitrogen (N 2 ), argon (Ar), etc., or reactive, e.g., oxygen (O 2 ), ozone (O 3 ), hydrogen peroxide (H 2 O 2 ), air, hydrogen (H 2 ), ammonia (NH 3 ), hydrogen fluoride (HF), hydrochloric acid (HCl), etc. In one embodiment, the gas portion includes only a single type of gas, for example, nitrogen (N 2 ). In another embodiment, the gas portion is a gas mixture that includes mixtures of various types of gases, such as: ozone (O 3 ), oxygen (O 2 ), carbon dioxide (CO 2 ), hydrochloric acid (HCl), hydrofluoric acid (HF), nitrogen (N2), and argon (Ar); ozone (O 3 ) and nitrogen (N 2 ); ozone (O 3 ) and argon (Ar); ozone (O 3 ), oxygen (O 2 ) and nitrogen (N 2 ); ozone (O 3 ), oxygen (O 2 ) and argon (Ar); ozone (O 3 ), oxygen (O 2 ), nitrogen (N 2 ), and argon (Ar); and oxygen (O 2 ), argon (Ar), and nitrogen (N 2 ). It should be appreciated that the gas portion can include essentially any combination of gas types as long as the resulting gas mixture can be combined with a liquid portion and a solid portion to form a tri-state compound that can be utilized in substrate cleaning or preparation operations. 
         [0048]    The liquid component, being a continuous medium, is one is one of de-ionized (DI) water, a hydrocarbon, a base fluid, a hydrofluoric acid (HF) solution, an ammonia based solution, or mixtures of DI water and chemicals. 
         [0049]    A bi-state compound is one that includes the solid component and a liquid component. For more information on tri-state compounds and the like, reference may be made to Provisional Application No. 60/755,377, filed Dec. 30, 2005, assigned to the assignee, and incorporated herein by reference. 
         [0050]      FIGS. 3A and 3B  illustrate alternate embodiments of a proximity head applying a non-Newtonian fluid  101  and a Newtonian fluid  102  to a surface of a substrate and the relative movement of the proximity head to the movement of the substrate. As can be seen in  FIG. 3A , the non-Newtonian fluid  101  applied to a surface of a substrate  110  between the surface  115  of the substrate  110  and a head surface of the proximity head  130  forms a containment wall  140  along two sides. A treatment region, defined by the two sides of the containment wall  140 , further defines a channel to receive a Newtonian fluid  102  applied through the proximity head. 
         [0051]    In one embodiment, the Newtonian fluid  102  can be applied at one extreme point of the channel such that the Newtonian fluid  102  flows in the channel towards the other extreme end. In another embodiment, the Newtonian fluid  102  is applied at the center of the channel such that the Newtonian fluid  102  flows from the center to the outer extremes of the treatment region. The Newtonian fluid  102  reacts with the contaminants on the surface of the substrate exposed to the treatment region and substantially removes the contaminants. 
         [0052]      FIG. 3B  illustrates a variation of  FIG. 3A . In the embodiment illustrated in  FIG. 3B , the non-Newtonian fluid  101  is applied between the surface  115  of the substrate  110  and a head surface of the proximity head such that the non-Newtonian fluid  101  forms a containment wall  140  along three sides. In this embodiment, a treatment region, defined by the containment wall  140 , receives a Newtonian fluid  102  applied through the proximity head such that the Newtonian fluid  102  flows in the treatment region away from the containment wall  140  of the non-Newtonian fluid  101 , as illustrated in  FIG. 3B . The Newtonian fluid  102  reacts with the contaminants on the surface  115  of the substrate  110  covered by the treatment region and substantially removes the contaminants. 
         [0053]      FIGS. 3C and 3D  illustrate alternate embodiments illustrated in  FIGS. 3A and 3B . In the embodiment illustrated in  FIG. 3C , a non-Newtonian fluid  101  is applied along an edge exclusion region between the surface  115  of the substrate  110  and a head surface of the proximity head such that the non-Newtonian fluid  101  forms a containment wall  140  along the edge exclusion region of the substrate  110 . In this embodiment, the containment wall  140  defines a treatment region covering the entire surface  115  of the substrate  110 . A Newtonian fluid  102  is applied through the proximity head such that the Newtonian fluid  102  flows within the containment wall  140  over the treatment region formed by the non-Newtonian fluid  101 , as illustrated in  FIG. 3C . The Newtonian fluid  102  reacts with the contaminants on the surface  115  of the substrate  110  within the treatment region and substantially removes the contaminants. 
         [0054]    In an alternate embodiment illustrated in  FIG. 3D , a second non-Newtonian fluid  101 -A is applied in place of a Newtonian fluid  102  illustrated in  FIG. 3C . In this embodiment, the containment wall  140 , formed by the first non-Newtonian fluid  101  as illustrated in  FIG. 3C , defines a treatment region covering the entire surface  115  of the substrate  110 . A second non-Newtonian fluid  101 -A is applied through the proximity head such that the second non-Newtonian fluid  101 -A flows within the containment wall  140  in the treatment region formed by the first non-Newtonian fluid  101 , as illustrated in  FIG. 3D . The second non-Newtonian fluid  101 -A reacts with the contaminants on the surface  115  of the substrate  110  within the treatment region and substantially removes the contaminants. 
         [0055]      FIG. 4  illustrates a simplified schematic representation of an apparatus containing a dual proximity head that is used to apply a non-Newtonian fluid  101  and a Newtonian fluid  102  to a surface  115  of a substrate  110 , in one embodiment of the invention. In this embodiment described in conjunction with the process operations of  FIG. 7 , a substrate  110  is received and mounted on a carrier  120  and moved along a plane as illustrated in operation  605 . The carrier  120  is configured to hold the substrate  110  along a plane, move the substrate  110  along a lateral axis and rotate the substrate  110  along an axis of rotation so that different portions of a surface  115  of the substrate  110  are exposed to a Newtonian fluid  102  applied to the surface  115  of the substrate  110 . The substrate  110  includes an edge exclusion region  113 . The carrier  120  includes a pin  122 , which receives and holds the substrate  110 , and motors and wheels (not shown) to move the substrate  110  along the lateral axis and to rotate the substrate  110  along the axis of rotation. The carrier  120  moves along the lateral axis so as to expose various portions of the substrate  110  to the Newtonian fluid  102 . The speed of the carrier along the lateral axis can be adjusted to allow substantial exposure of the surface  115  of the substrate  110  to the Newtonian fluid  102  for effective removal of contaminants from the surface  115  of the substrate  110 . 
         [0056]    In addition to a lateral movement, the carrier  120  is configured to rotate the substrate along the axis of rotation. The substrate is rotated at a velocity so as to enable substantial exposure of the surface of the substrate to the Newtonian fluid  102  for effective removal of the contaminants from the surface  115  of the substrate  110 . The embodiment illustrated in  FIG. 4  further illustrates application of the Newtonian fluid  102  at the center of the treatment region and removed from the extreme ends of the treatment region such that the Newtonian fluid  102  flows within the treatment region substantially removing the contaminants from the surface of the substrate exposed to the treatment region  205 . 
         [0057]    Continuing reference to  FIG. 4 , two proximity heads  130  and  135  are mounted such that they are parallel to each other and provide appropriate space for the carrier  120  with the substrate  110  to move along an axis between the two proximity heads  130  and  135  such that the proximity heads  130  and  135  cover at least a portion of the top and bottom surfaces of the substrate  115 , respectively. A non-Newtonian fluid applicator in the proximity heads  130  and  135  is used to apply a non-Newtonian fluid  101  between the surface  115  of the substrate  110  and the head surface of the proximity heads  130  and  135 , as illustrated in operation  610 . The non-Newtonian fluid applicator (not shown) includes a reservoir to hold the non-Newtonian fluid  101  with an inlet for receiving the non-Newtonian fluid  101  and an outlet for supplying the non-Newtonian fluid  101  to the surface of the substrate  115  through the proximity heads  130  and  135 . The non-Newtonian fluid applicator supplies the non-Newtonian fluid  101  in the form of a fluid meniscus to the surface  115  of the substrate  110 . 
         [0058]    The non-Newtonian fluid  101  forms a containment wall  140  defining a treatment region  205  on the respective surfaces  115  of the substrate  110 . In the embodiment illustrated in  FIG. 4 , a treatment region  205  is formed at the top and bottom surfaces  115  of the substrate  110  covering the entire surface  115  of the substrate  110 , by applying the non-Newtonian fluid  101  at the edge exclusion region  113  of the top and bottom surfaces  115  of the substrate  110 . 
         [0059]    A Newtonian fluid applicator in or connected to the proximity heads  130  and  135  is used to apply a Newtonian fluid  102  between the respective surfaces  115  of the substrate  110  and the respective head surface of the proximity heads  130  and  135  such that the Newtonian fluid  102  is substantially contained within the treatment region  105  formed on the top and bottom surfaces  115  of the substrate  110 , as illustrated in operation  615 . The Newtonian fluid applicator (not shown) includes a reservoir for the Newtonian fluid  102  with an inlet and a pair of outlets. The inlet is used for receiving cleaner and fresher Newtonian fluid  102  into the Newtonian fluid applicator. 
         [0060]    A first outlet is used for supplying the Newtonian fluid  102  to the surface of the substrate through the proximity heads  130  and  135 . A second outlet at the Newtonian fluid applicator is used to remove the Newtonian fluid mixed with the contaminants so that cleaner Newtonian fluid  102  can be introduced for more effective cleaning. The Newtonian fluid applicator supplies the Newtonian fluid  102  in the form of a fluid meniscus to the surface  115  of the substrate  110  within the treatment region  205 . A channel defined by the containment wall  140  and formed within the treatment region  205  enables the Newtonian fluid  102  to flow between the walls  140  of the non-Newtonian fluid  101 . The Newtonian fluid  102  flowing in the channel acts on one or more contaminants and removes the contaminants from the top and bottom surfaces  115  of the substrate  110  at the treatment region  205 , as illustrated in operation  620 . 
         [0061]    The speed of the carrier  120  carrying the substrate  110  may be adjusted so that the pressure of the Newtonian fluid  102  exerted on the non-Newtonian fluid  101  when applied by the proximity heads  130  and  135  are counter-balanced by a shift of non-Newtonian fluid  101  caused by the movement of the carrier  120 . Similarly, the thickness of the non-Newtonian fluid  101  can be adjusted based on one or more characteristics of the Newtonian fluid  102  in order to enable the non-Newtonian fluid  101  to substantially contain the Newtonian fluid  102 . 
         [0062]    In another embodiment, the non-Newtonian fluid  101  is applied between the surface of a carrier  120  and the head surface of the proximity head at an area on the carrier  120  just outside the edge exclusion region  113  of the substrate  110  received on the carrier  120  so that the non-Newtonian fluid  101  forms a treatment region  205  that covers the entire top and bottom surface  115  of the substrate  110 . In this embodiment, the containment wall  140  of non-Newtonian fluid meniscus forms a circular barrier between the head surface of the proximity head  130  and the top surface of the carrier  120  just outside the edge exclusion region of the substrate  113 . In the embodiments discussed above with reference to  FIG. 4 , the containment wall  140  of the non-Newtonian fluid  101  forms a circular barrier between the head surface of the proximity heads and the top and bottom substrate surfaces  115 . 
         [0063]    However, it is not necessary that the entire top and bottom surface  115  of the substrate  110  be enclosed by the treatment region. In another embodiment, the proximity heads  130  and  135  can be used to apply the non-Newtonian fluid  101  to the surface  115  of the substrate  110  such that a treatment region  205  is formed at the top and bottom surface  115  of the substrate  110  covering only a portion of the surface  115  of the substrate  110 . In this embodiment, the substrate  110 , in addition to being moved along a lateral axis, is rotated along an axis of rotation when the substrate  110  is under the proximity heads  130  and  135  so that different portions of the surface  115  of the substrate  110  are substantially exposed to the Newtonian fluid  102  contained within the treatment region  205 . 
         [0064]    In this embodiment, the proximity heads may not necessarily be a “head” in configuration, but may be any suitable configuration, shape, and/or size such as, for example, a manifold, a circular puck, a bar, a square, an oval puck, a tube, plate, etc., as long as the non-Newtonian fluid applicator and the Newtonian fluid applicator may be configured in a manner that would enable the generation of a controlled, stable, manageable fluid meniscus of non-Newtonian  101  and Newtonian fluids  102 . 
         [0065]    The embodiments of the current invention are not restricted to applying a non-Newtonian fluid  101  and a Newtonian fluid  102  to the surface of the substrate. The embodiments of the current invention illustrated in  FIG. 4  may also be used to apply more than one non-Newtonian fluid  101  to the surface of the substrate. In this embodiment, the proximity head is equipped with two non-Newtonian fluid applicators. A first non-Newtonian fluid applicator is used to supply a first non-Newtonian fluid  101  between the surface  115  of the substrate  110  and the head surface of the proximity heads  130  and  135  such that the first non-Newtonian fluid  101  forms a containment wall  140  defining a treatment region  205  on the respective surfaces  115  of the substrate  110 . Although the embodiment illustrated in  FIG. 4  shows the treatment region  205  covering the entire top and bottom surface  115  of the substrate  110 , the treatment region  205  may cover only a portion of the top and bottom surface  115  of the substrate  110 . A second non-Newtonian fluid applicator is used to apply a second non-Newtonian fluid  101 -A, that is different from the first non-Newtonian fluid  101 , to the treatment region  205  such that the second non-Newtonian fluid  101 -A is substantially contained within the treatment region formed on the top and bottom surfaces  115  of the substrate  110 . The second non-Newtonian fluid  101 -A flowing within the treatment region  205  reacts with the contaminants present on the surface of the substrate exposed to the treatment region  205  substantially removing the contaminants. 
         [0066]    The embodiments of the current invention is not restricted to applying a single type of Newtonian fluid  102  to the surface of the substrate. The embodiments of the current invention can also be used to apply more than one type of Newtonian fluid  102  to the surface of the substrate.  FIG. 5  illustrates a variation of a proximity head  130  used in applying more than one type of Newtonian fluid  102  to the surface  115  of the substrate  110 . 
         [0067]    In the embodiment illustrated in  FIG. 5 , a non-Newtonian fluid  101  is applied using a proximity head  130  between the surface  115  of the substrate  110  and a head surface of the proximity head  130 . The applied non-Newtonian fluid  101  defines a containment wall  140  along one or more sides between the head surface and the substrate surface  115 . In this embodiment, the non-Newtonian fluid  101  is applied along an edge exclusion region  113  of the substrate  110  such that the containment wall  140  encloses a treatment region  205  covering the remainder of the substrate surface  115 . 
         [0068]    A first Newtonian fluid  102 -A is applied using the proximity head  130  to the surface  115  of the substrate  110  such that the first Newtonian fluid  102 -A is substantially contained within a first treatment sub-region  207  in the treatment region  205  of the substrate  110  defined by the containment wall  140 . A second Newtonian fluid  102 -B is applied using the proximity head  130  to the surface of the substrate  115  so that the second Newtonian fluid  102 -B is substantially contained within a second treatment sub-region  209  in the treatment region  205  of the substrate  110 . The first Newtonian fluid  102 -A and the second Newtonian fluid  102 -B are different from each and are chosen such that they are substantially immiscible with the non-Newtonian fluid  101 . The first treatment sub-region  207  is separated from the second treatment sub-region  209  by the non-Newtonian fluid  101 . The two Newtonian fluids  102 -A and  102 -B independently act on the various contaminants that are present on the surface  115  of the substrate  110  when applied at the treatment region  205  and help in substantially removing the contaminants from the surface  115  of the substrate  110 . 
         [0069]    In an alternate embodiment of  FIG. 5 , a second and third non-Newtonian fluids  101 -A and  101 -B are applied within the treatment region  205  instead of a first and second Newtonian fluids  102 -A and  102 -B. In this embodiment, a first non-Newtonian fluid  101  is applied using a proximity head  130  between the surface  115  of the substrate  110  and a head surface of the proximity head  130 . The applied non-Newtonian fluid  101  defines a containment wall  140  along one or more sides between the head surface and the substrate surface  115 . In this embodiment, the first non-Newtonian fluid  101  is applied along an edge exclusion region  113  of the substrate  110  such that the containment wall  140  encloses a treatment region  205  covering the remainder of the substrate surface  115 . A second non-Newtonian fluid  101 -A is applied using the proximity head  130  to the surface  115  of the substrate  110  such that the second non-Newtonian fluid  101 -A is substantially contained within a first treatment sub-region  207  in the treatment region  205  of the substrate  110  defined by the containment wall  140 . A third non-Newtonian fluid  101 -B is applied using the proximity head  130  to the surface of the substrate  115  so that the third non-Newtonian fluid  101 -B is substantially contained within a second treatment sub-region  209  in the treatment region  205  of the substrate  110 . The second and third non-Newtonian fluids  101 -A and  101 -B are different from each other and from the first non-Newtonian fluid  101  and are chosen such that they are substantially immiscible with the first non-Newtonian fluid  101 . The first treatment sub-region  207  is separated from the second treatment sub-region  209  by the first non-Newtonian fluid  101 . The two non-Newtonian fluids  101 -A and  101 -B within the treatment region independently act on the various contaminants that are present on the surface  115  of the substrate  110  exposed at the treatment region  205  and help in substantially removing the contaminants from the surface  115  of the substrate  110 . 
         [0070]    In an alternate embodiment, the first non-Newtonian fluid  101  is applied to the surface of the substrate between the head surface of the proximity head and the surface  115  of the substrate  110  defining a treatment region  205 . In this embodiment, a second non-Newtonian fluid  101 -A is applied to the surface of the substrate such that it is contained within a first sub-region  207  of the treatment region  205 . A Newtonian fluid  102  is applied to the surface  115  of the substrate  110  such that the Newtonian fluid  102  is substantially contained within the second sub-region  209  of the treatment region  205 . The second non-Newtonian fluid  101 -A and the Newtonian fluid  102  are chosen such that they are different from the first non-Newtonian fluid  101  and are substantially immiscible with the first non-Newtonian fluid  101 . The first treatment sub-region  207  is separated from the second treatment sub-region  209  by the first non-Newtonian fluid  101 . The second non-Newtonian fluid  101 -A and the Newtonian fluid  102  within the treatment region independently act on the various contaminants that are present on the surface  115  of the substrate  110  exposed in the treatment region  205  and help in substantially removing the contaminants from the surface  115  of the substrate  110 . 
         [0071]    In another embodiment illustrated in  FIG. 6A , the treatment region  205  is defined by the containment wall  140  that covers only a portion of the surface  115  of the substrate  110 . In this embodiment, various portions of the surface  115  of the substrate  110  are continuously exposed to a first and second Newtonian fluids  102 -A and  102 -B by moving the surface  115  of the substrate  110  and/or the proximity head  130  so that each of the two Newtonian fluids  102 -A and  102 -B independently act on the contaminants present on the surface within the treatment region substantially removing them from the surface  115  of the substrate  110 . 
         [0072]    In an alternate embodiment illustrated in  FIG. 6B , a second and third non-Newtonian fluids  101 -A and  101 -B are applied to the surface  115  of the substrate  110  such that the second and third non-Newtonian fluids  101 -A and  101 -B are substantially contained within the first sub-region and second sub-region  207  and  209  within the treatment region  205 . As mentioned with reference to  FIG. 6A , various portions of the substrate  110  are continuously exposed to the two non-Newtonian fluids  101 -A and  101 -B contained within the treatment region  205  by moving the surface of the substrate  110  and/or the proximity head  130 . The two non-Newtonian fluids  101 -A and  101 -B independently act on the contaminants found on the surface  115  of the substrate  110  substantially removing them. 
         [0073]    In yet another embodiment illustrated in  FIG. 6C , a second non-Newtonian fluid  101 -A is applied to the first sub-region  207  within the treatment region  205  and a Newtonian fluid  102  is applied to the second sub-region  209  within the treatment region  205 . In this embodiment as mentioned with reference to  FIGS. 6A and 6B , various portions of the surface  115  of the substrate  110  are continuously exposed to the second non-Newtonian fluid  101 -A and the Newtonian fluid  102  by moving the surface  115  of the substrate  110  and/or the proximity head  130  so that each of the second non-Newtonian fluid  101 -A and the Newtonian fluid  102  independently act on the contaminants present on the surface within the treatment region substantially removing them from the surface  115  of the substrate  110 . 
         [0074]    In a typical fabrication process of a substrate, chemistry used in the fabrication or the external uncontrolled environment may cause oxidation of features or layers formed at the substrate. This oxidation may affect later processing. For instance, excessive oxidation may prevent some layers to properly adhere or can cause less than desired conductive interfaces between layers or features. For example, in electroless deposition of metal layers, the electroless plating process is highly dependent on the surface characteristics and composition of the substrate  110 . When oxidation occurs on the surface of the substrate, the electroless deposition process is inhibited by the formation of an atomically thin metal oxide layer formed due to the presence of oxygen. An additional step of removing the oxidized (metal oxide) layer has to be performed prior to the electroless deposition process resulting in increased cost, and time for the overall fabrication. Managing surface preparation sequence prior to subsequent fabrication is critical in the overall fabrication process. 
         [0075]    In an embodiment, illustrated in  FIGS. 8A-8D , a proximity head  130  is used in providing a substantially oxygen-free environment within a treatment region on the substrate in order to facilitate forming other features, structures or layers on a surface  115  of a substrate  110 . Referring to  FIG. 8A , a non-Newtonian fluid  101  is applied using the proximity head  130  between the surface  115  of the substrate  110  and a head surface of the proximity head  130 . The applied non-Newtonian fluid  101  defines a containment wall  140  along a containment region  205  between the head surface and the surface  115  of the substrate  110 . In one embodiment, the non-Newtonian fluid  101  is applied along an edge exclusion region  113  of the substrate  110  such that the containment wall  140  encloses a treatment region  205  covering an entire active surface  115  of the substrate  110 . 
         [0076]    In one embodiment, an inert gas may be applied to the treatment region  205  using the proximity head  130 , to the surface  115  of the substrate  110 , such that the inert gas occupies the treatment region  205 , displacing any chemistries or gases that might be present within the treatment region  205 . The application of the inert gas to the treatment region  205  provides a substantially oxygen-free environment in the treatment region  205 , that is substantially isolated from an external uncontrolled environment. 
         [0077]    By creating a substantially oxygen-free environment in the treatment region and substantially isolating the treatment region  205  with the containment wall  140 , it is possible to clean, prepare, or fabricate different layers, features, or structures (such as electroplating or electroless plating, etching, etc) immediately after processing of other features, layers or structures, while preventing the substrate from coming into contact with the external uncontrolled environment (e.g. environment having more oxygen or other undesired elements including moisture than may be desired). 
         [0078]    The inert gas, as referred herein, is used to control the treatment region between the head surface of the proximity head and the surface of the substrate, wherein the non-Newtonian fluid creates an enclosed treatment region  205 . In one embodiment, an inert gas controlling system (not shown) may be coupled to one or more ports of the proximity head  130  via a manifold (not shown). The manifold uses computer controls or manual controls to control what is introduced through the ports into the treatment region. 
         [0079]    In one example, the inert gas controlling system may include pumps, gauges, controls and valves that meter and control the pumping of inert gas into the treatment region and the oxygen or chemicals out of the treatment region. Clean room facilities (not shown) may also couple to the inert gas controlling system, so that inert gas can be applied through the proximity head, and thus allows the replacement of oxygen with an inert gas. (i.e., the space previously occupied by oxygen or chemicals containing oxygen is now filled with inert gas). The pumps that remove the oxygen or other chemicals are monitored, so that proper conditions can be maintained during any stages of fabrication process. Meters, manual controls and/or computer controls can monitor and adjust the pumping and flows of inert gases, such as N2, Ar, He, Ne, Kr, Xe, etc. with out limitation. 
         [0080]    Referring to  FIG. 8B , a barrier layer  820  may be formed at the treatment region. Barrier materials may be, for instance, TaN, Ta, Ru, among others. Barrier layer  820  can be formed using an electroless plating process, for example. An etching chemical may be introduced into the treatment region to allow removal of oxides, or further processing of the barrier layer  820 . The cleaning or etching of the barrier layer  820 , however, is done outside of the presence of oxygen, as the treatment region  205  is kept substantially oxygen free. The preparation of the barrier layer  820  may be followed by another inert gas application so that chemicals used in forming the barrier layer  820  can be substantial removed, treated, cleaned, etc., as shown in  FIG. 8C . 
         [0081]    In addition to providing a substantially oxygen-free environment within the treatment region  205 , the defined embodiments prevent uncontrolled de-wetting of the surface of the substrate by controlling the environment within the treatment region, thereby providing for a highly efficient fabrication process. 
         [0082]    As illustrated in  FIG. 8D , the fabrication process may continue with another plating application. The plating application may use an electroplating or electroless plating process to deposit the plating layer on a layer of the substrate  110 . The electroplating process, where contact with the substrate is required, or electroless plating process used in forming a plating layer on the surface of the substrate may be configured in any number of forms. 
         [0083]    Example systems and processes for performing plating operations are described in more detail in: (1) U.S. Pat. No. 6,864,181, issued on Mar. 8, 2005; (2) U.S. patent application Ser. No. 11/014,527 filed on Dec. 15, 2004 and entitled “WAFER SUPPORT APPARATUS FOR ELECTROPLATING PROCESS AND METHOD FOR USING THE SAME”; (3) U.S. patent application Ser. No. 10/879,263, filed on Jun. 28, 2004 and entitled “METHOD AND APPARATUS FOR PLATING SEMICONDUCTOR WAFERS”; (4) U.S. patent application Ser. No. 10/879,396, filed on Jun. 28, 2004 and entitled “ELECTROPLATING HEAD AND METHOD FOR OPERATING THE SAME”; (5) U.S. patent application Ser. No. 10/882,712, filed on Jun. 30, 2004 and entitled “APPARATUS AND METHOD FOR PLATING SEMICONDUCTOR WAFERS”; (6) U.S. patent application Ser. No. 11/205,532, filed on Aug. 16, 2005, and entitled “REDUCING MECHANICAL RESONANCE AND IMPROVED DISTRIBUTION OF FLUIDS IN SMALL VOLUME PROCESSING OF SEMICONDUCTOR MATERIALS”; and (7) U.S. patent application Ser. No. 11/398,254, filed on Apr. 4, 2006, and entitled “METHODS AND APPARATUS FOR FABRICATING CONDUCTIVE FEATURES ON GLASS SUBSTRATES USED IN LIQUID CRYSTAL DISPLAYS”; each of which is herein incorporated by reference. Thus, embodiments of the current invention may be used in providing a substantially oxygen-free environment within a treatment region. 
         [0084]    Although the foregoing invention has been described in some detail for purposes of clarity of understanding, it will be apparent that certain changes and modifications can be practiced within the scope of the appended claims. Accordingly, the present embodiments are to be considered as illustrative and not restrictive, and the invention is not to be limited to the details given herein, but may be modified within the scope and equivalents of the appended claims.