Patent Publication Number: US-2015082580-A1

Title: Turbine powered cleaning apparatus

Description:
RELATED APPLICATIONS 
     This application is a divisional of U.S. patent application Ser. No. 12/939,479, filed on Nov. 4, 2010, the contents of which are hereby incorporated by reference as if set forth in their entirety. 
    
    
     TECHNICAL FIELD 
     The invention relates, most generally, to a vacuum powered turbine cleaning device used to remove particles from semiconductor manufacturing tools. 
     BACKGROUND 
     The semiconductor manufacturing industry utilizes various types of manufacturing or processing equipment, also known as processing tools, to fabricate advanced semiconductor integrated circuit devices and other devices that are highly integrated. These highly integrated devices are formed to very tight design tolerances and include increasingly smaller feature sizes. As feature sizes continue to shrink further within the sub-micron range, the devices are more susceptible to damage due to particle contamination. Particle contamination therefore becomes an increasingly serious problem as even the smallest particles and very low particle densities must be controlled because device functionality can be destroyed by even one small particle. The manufacturing tools used to fabricate semiconductor devices must therefore be maintained at high levels of cleanliness. It is therefore of critical importance to prevent the accumulation of particles in such manufacturing tools and to completely remove any and all particles from such manufacturing tools when cleaning or other maintenance procedures are carried out upon the tool. 
     Many processing tools are available and used to coat semiconductor substrates with photoresist or other photosensitive materials. Much of the foreign material introduced into the processing, i.e. coating, chamber is unused and must be removed from the processing environment. This includes the photoresist materials that are spun off the edges of semiconductor substrates that rotate at high speeds. The processing tools include outlet and exhaust ports and tubes through which the unused material is expelled. A buildup of residue of the unused coating material can accumulate in these ports and tubes. The buildup in the tubes can clog the tubes, block the ports or restrict exhaust flow. Moreover, the residue can become a major source of particle contamination, especially as it dries and delaminates. Defects that commonly occur on substrate surfaces result from particles that originate from exhaust ducts. As a result, these ports and tubes are cleaned regularly. When such exhaust systems are cleaned, they must therefore be thoroughly and completely cleaned so as to remove all particles and prevent the particles from becoming disgorged back into the main processing, i.e. coating, chamber of the processing system where they can contaminate devices and ruin device functionality. The cleaning process itself must be carried out in a manner that does not generate particles. 
     Conventional cleaning methods are carried out using brushes such as bottle-brushes, i.e. long, cylindrical brushes with brittle bristles designed to extend into and clean bottles. These bottle-brushes are inserted into the exhaust ports and used to dislodge and remove particles. When this occurs, however, many particles that become generated or dislodged from the residue formed in the exhaust port, are spread throughout the coating chamber and eventually find their way onto substrate surfaces. This re-introduction of particles back into the coating, i.e. processing chamber during the cleaning procedure, must be eliminated. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
       The disclosure is best understood from the following detailed description when read in conjunction with the accompanying drawing. It is emphasized that, according to common practice, the various features of the drawing are not necessarily to scale. On the contrary, the dimensions of the various features are arbitrarily expanded or reduced for clarity. Like numerals denote like features throughout the specification and drawing. 
         FIG. 1  is a side view in partial cross-section, illustrating an exemplary turbine-powered cleaning apparatus according to the disclosure; 
         FIG. 2A  is a side view in partial cross-section, illustrating a further exemplary turbine-powered cleaning apparatus according to the disclosure; 
         FIGS. 2B and 2C  show a friction fitting used in the embodiment of  FIG. 2A ; 
         FIGS. 2D and 2E  show another embodiment of a friction fitting that includes a filter; 
         FIG. 3  is a side view illustrating a further exemplary turbine-powered cleaning apparatus being used in a cleaning operation; 
         FIG. 4A  is a side view illustrating another exemplary embodiment of a turbine-powered cleaning apparatus according to the disclosure; 
         FIG. 4B  is a side view illustrating another exemplary embodiment of a turbine-powered cleaning apparatus according to the disclosure; and 
         FIG. 5  is a side view showing yet another exemplary embodiment of a turbine-powered cleaning apparatus according to the disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     The disclosure provides a brush or other cleaning member or device that is turbine-powered. A multi-rotor turbine assembly is affixed within a tube or hose that is coupled to an air pump such as a vacuum system. The fluid flow causes the rotors and thus the shaft of the turbine assembly to rotate. The head of the brush or other cleaning member is affixed to the shaft and rotates along with the shaft and the bristles or other cleaning media extend outwardly due to centrifugal force, dislodging particles which are sucked into the tube through an annular opening at the end of the tube due to the vacuum action. 
       FIG. 1  is a side view in partial cross-section illustrating an exemplary turbine-powered cleaning apparatus according to the disclosure. The turbine-powered cleaning member embodiment illustrated in  FIG. 1  is turbine-powered brush  10 . Turbine-powered brush  10  includes tube  12 , head  14  and turbine assembly  16  within tube  12 . Tube  12  may be a vacuum hose or other suitable tube such as a Teflon tube but tube  12  may be formed of various other suitable materials in other exemplary embodiments. Tube  12  may be flexible or rigid. Tube  12  includes inner surface  20 , outer surface  22  and diameter  24 . Tube  12  is shown in a cut-away cross section, with other components including the components inside tube  12  and the head portion, shown in side view: 
     In one exemplary embodiment, diameter  24  of tube  12  may be 1 inch, but in other exemplary embodiments, diameter  24  may range from 0.25 inches to 4 or 5 inches. Tube  12  includes first end  28  and a second end coupled to a vacuum source, air pump, or other source that causes fluid flow as indicated by fluid flow arrow  32  at vacuum source end  30 . In one exemplary embodiment, tube  12  may be several feet long and vacuum source end  30  is coupled to a vacuum source. In one exemplary embodiment, vacuum source end  30  may represent that tube  12  includes a length of about 8 inches to about 24 inches and may be attachable, using any of various mechanical means such as threads, to a conventional vacuum hose such as a clean room vacuum hose. The vacuum source may be a clean room vacuum system such as an exemplary clean room vacuum system manufactured by Nilfisk CFM of Malvern, Pa. but other suitable clean room or other vacuum systems may be used as well. 
     Various air pumps or vacuum systems may be used to produce fluid flow which may advantageously be air flow such as flow of the clean room air. Various suitable clean room vacuum systems or other commercially available vacuum sources may be used. Fluid flow using commercially available vacuum sources may range from about 50-300 cubic feet per minute, but other fluid flow values may be attained using other vacuum sources and may be used in other exemplary embodiments. 
     Turbine assembly  16  includes a plurality of rotors  36  that cause shaft  38  to rotate when rotors  36  rotate due to fluid flow as indicated by fluid flow arrow  32 . Fluid flow  32  created by the vacuum source can be used to cause the rotary motion of rotors  36  and shaft  38  at speeds of 15,000 RPM or greater in one exemplary embodiment. Rotors  36  may be formed of thin-gauge anodized steel or other suitable rigid material such as other metals and the number of illustrated rotors—five—is intended to be exemplary only. Shaft  38  may be formed of steel or other metals or various other suitable non-deformable and rigid materials in various exemplary embodiments. 
     Shaft  38  extends through support sleeve  40  and within chuck  42  and is coupled to head  14  such that, when shaft  38  rotates, head  14  also rotates. Support sleeve  40  is centrally and fixedly coupled to tube  12  by means of mounting screws  44  and alignment screws  46  in the exemplary embodiment, but other suitable coupling means may be used in other exemplary embodiments. In various other exemplary embodiments, such as one that will be shown in  FIG. 2 , turbine powered brush  10  may be removable from tube  12  and may be secured in place within tube  12 , using various friction-fitting means. Again referring to  FIG. 1 , according to the illustrated embodiment, mounting screws  40  are received within openings in tube  12 . Support sleeve  40  may be formed of a poly-carbonate material or Lexan® or other suitable materials. Shaft  38  rotates freely within support sleeve  40 . Chuck  42  secures shaft  38  to head  14 . Chuck  42  extends into head  14  and surrounds shaft  38 . Shaft  38  and chuck  42  protrude from tube  12  at terminus  50  of first end  28  which includes annular opening  52 . Annular opening  52  surrounding the head  14 /chuck  42  assembly serves as an air intake when the air pump or vacuum source is turned on to create fluid flow  32 . Additional support for shaft  38  may be supplied by bearing race  56  which is in contact with and combines with thrust bearing  58  which contains ball bearings. Thrust bearing  58  is coupled to and rotates along with chuck  42  due to the ball bearings which facilitate low friction movement and load bearing capabilities. Bearing race  56  and thrust bearing  58  may be used in conjunction with one or more washers to prevent slippage but these components are intended to be exemplary only. Various other thrust bearings or other mechanisms capable of performing the same function may be used in other exemplary embodiments. Chuck  42  and thrust bearing  58  may be formed of an alloy such as brass but other metals and alloys may be used in other exemplary embodiments. 
     Head  14  may be formed of Teflon or other suitable non-corrosive materials. Bristles  62  may be formed of stainless steel, Kevlar, nylon or other similar materials, or other suitable materials. In the illustrated embodiment, it can be seen that there are two axially spaced rows of bristles  62 . According to one exemplary embodiment, bristles  62  may include bristles formed of two or more different materials such as the aforementioned materials. In one exemplary embodiment, one of the rows of bristles  62  may be formed of one material and another of the rows of bristles  62  may be formed of a further material. Bristles  62  extend outwardly due to centrifugal force when shaft  38  and head  14  rotate. Bristles  62  may be secured to head  14  by an o-ring  66  received within a corresponding channel that extends around the periphery of head  14 . Other bristle arrangements may be used in other exemplary embodiments. According to one exemplary embodiment, only one row of bristles that extends peripherally around head  14  to form a row that is substantially orthogonal to shaft  38 , may be used and may include bristles formed of two or more different materials. Balancing set screws  64  or other suitable means may be used to properly balance head  14 . 
     Tube  12  may be rigid or flexible according to various exemplary embodiments and may be stabilized by flanges  68  that extend circumferentially around tube  12 , contacting outer surface  22 . Wall fenders  70  may be o-rings or other pliable materials that extend around flanges  68  and may be received within a corresponding channel  72  of flange  68 . Wall fenders  70  and flanges  68  are also shown in cut-away cross-sectional view. Laminar flow vanes  76  may be included within tube  12  to stabilize tube  12  and guide fluid flow  32 . Laminar flow vanes  76  may be formed of poly-carbonate, Lexan® or other suitable materials and may advantageously maintain fluid flow in a laminar state. 
       FIG. 2A  is a side view showing another exemplary embodiment of a turbine-powered cleaning brush. In the embodiment in  FIG. 2A , also shown with tube  12 , flanges  68  and wall fenders  70  shown in cutaway cross section, winged friction fitting member  75  is secured within tube  12 . Winged friction fitting member  75  is shown in front and side views in  FIG. 2B  and  FIG. 2C , respectively, as well. Winged friction fitting member  75  includes centrally disposed support sleeve  40  that receives shaft  38  and also ribs  77  that extend from support sleeve  40  and abut inner surface  20  of tube  12 . Winged friction fitting member  75  is sized in conjunction with tube  12  to fit snugly within tube  12 . End faces  81  of ribs  77  contact inner surfaces  20 . According to one exemplary embodiment, winged friction fitting member  75  may work in conjunction with flange  68  and wall fenders  70  to form a friction fitting. Flange  68  may be formed of metal or other suitable rigid materials and may fit snugly on an opposed outer surface  22  of tube  12 . According to one exemplary embodiment, ribs  77  may be formed of metals, plastics, other polymers or other suitable rigid materials. According to other exemplary embodiments, ribs  77  may be spring loaded members that may be compressible and urge an outward force to provide contact to inner surfaces  20 . 
       FIGS. 2D and 2E  illustrate another exemplary embodiment of winged friction fitting member  75  in front and side views, respectively. According to this illustrated embodiment, winged friction fitting member  75  includes filter  79 . Filter  79  may be used to trap large particles upstream from turbine assembly  16 . The embodiment in which filter  79  is a screen, is intended to be exemplary only and in another exemplary embodiments, other filters types may be used. In addition to the illustrated embodiment in which filter  79  is integrated within winged friction fitting member  75 , filter  79  may be positioned in various other locations within tube  12 , in other exemplary embodiments. 
       FIG. 3  shows turbo-powered brush  10  being used in a cleaning operation. In the illustrated embodiment, the maximum diameter of head  14  is less than diameter  24  of tube  12  but the diameter of head  14  plus bristles  62  and  84  extending outwardly, is greater than diameter  24 . According to various exemplary embodiments, head  14  may be removable and interchangeable with other heads having different diameters. As such, the maximum diameter of head  14  may be less than, equal to or greater than diameter  24  of tube  12 . Semiconductor processing tool  90  includes exhaust duct  80  which extends from processing chamber  94 . Exhaust duct  80  includes residue  82  adhering to its inner surfaces. Semiconductor processing tool  90  may be a coating tool in one exemplary embodiment in which residue  82  may be unused photoresist or ARC (anti-reflective coating) or any of various other coating materials applied to a substrate during semiconductor fabrication operation such as a coating operation. Turbine-powered brush  10  may be used to clean various other ducts, exhaust ports and outlet tubes of other semiconductor manufacturing equipment in other exemplary embodiments. 
     Fluid flow is indicated by fluid flow arrow  32  and is a result of tube  12  being coupled to a vacuum source such as vacuum system  57  which is an air pump or other fluid flow source in some embodiments. According to the illustrated embodiment, head  14  includes bristles  62  and further bristles  84 , either or both of which may be formed of stainless steel, nylon, Kevlar®, combinations thereof, or other suitable materials. Centrifugal force causes each of the aforementioned bristles to extend outwardly and rotate, dislodging particles  88  from residue  80  within duct  80 . Fluid flow  32  causes the turbine (not shown in  FIG. 3 ) to cause head  14  and bristles  66 ,  84  to rotate and also creates air flow as indicated by air flow arrows  92 . Air and particles  88  enter tube  12  at terminus  50  through annular opening  52 . With liberated particles  88  sucked into tube  12  as such, the particles do not reenter processing chamber  94  of semiconductor processing tool  90  and therefore do not create particle contamination. 
       FIG. 4A  shows another exemplary embodiment of turbo-powered brush  10  with bristles  62  and further bristles  84  extending from head  14 . Lumen  96  is affixed to outer surface  22  of tube  12  in  FIG. 4A  and may be secured in place by of flanges  68  and wall fenders  70 . In other exemplary embodiments, such as in  FIG. 4B , the walls of tube  12  may be thick enough to accommodate a lumen therein.  FIG. 4B  shows lumen  196  indicated by dashed lines, disposed within the walls of tube  12 , which are formed of a thickness sufficient to accommodate a lumen inside the walls. According to either of the embodiments of  FIGS. 4A and 4B , the lumen is attached to fluid source  99  at end  98  and is capable of dispensing the fluid at outlet port  100 . The fluid may be acetone, isopropyl alcohol, or other suitable cleaning fluids or solvents that are useful in cleaning surfaces and/or dissolving materials in semiconductor processing tools, or both. Cleaning fluid  102  may be dispensed as a spray or as a mist and may exit lumen  96  as cleaning fluid  102  at outlet port  100 . The flow of cleaning fluid  102  is controlled to work in conjunction with the cleaning action of bristles  62 ,  84  and also in conjunction with the vacuum provided due to the vacuum or other air pump affixed to tube  12 . In this manner, cleaning fluid  102  dispensed at outlet port  100  may be sucked back into tube  12  due to the vacuum force after moistening residue or other materials being removed by turbo-powered brush  10 . 
       FIG. 5  shows another exemplary cleaning device according to the disclosure. Turbo powered cleaning apparatus  110  includes several of the previously described features. In the illustrated exemplary embodiment of  FIG. 5 , affixed to head  14  is cleaning member  112 . In one exemplary embodiment, cleaning member  112  consists of a plurality of discrete cleaning member sections that extend radially outward from head  14  and shaft  38  and are positioned generally linearly along a single row that extends substantially orthogonal to shaft  38  and peripherally around head  14 . According to one exemplary embodiment, each of a plurality of discrete sections of cleaning member  112  may be formed of a sponge material or other compressible porous material. According to other exemplary embodiments, each of a plurality of discrete sections of cleaning member  112  may be formed of intertwined mesh such as a scouring pad. Other materials may be used in other exemplary embodiments and cleaning member  112  may take on other shapes besides the illustrated embodiment of discrete portions. According to another exemplary embodiment, cleaning member  112  may be a member that extends continuously around head  14  instead of a plurality of discrete sections. 
     According to one aspect of the disclosure, a cleaning apparatus is provided. The cleaning apparatus comprises a tube having a first end coupled to an air pump and a rotatable cleaning device disposed at a second end, the rotatable cleaning device including a turbine with an axial shaft protruding from the second end, a rotatable head coupled to the shaft at the second end, and, bristles extending outwardly from the rotatable head. 
     According to another aspect, the disclosure provides a vacuum-powered brush. The vacuum-powered brush comprises a vacuum system and a vacuum hose having a first end coupled to the vacuum system. The vacuum-powered brush further comprises a rotatable brush disposed at a second end of the vacuum tube, the rotatable brush including a turbine with an axial shaft that protrudes from the second end of the tube and a plurality of rotor blades disposed within the hose and a rotatable brush head coupled to the shaft at the second end. 
     According to another aspect, the disclosure provides a cleaning apparatus comprising a tube having a first end coupled to an air pump and a rotatable cleaning device disposed at a second end. The rotatable cleaning device comprises a turbine with an axial shaft protruding from the second end, a head fixedly coupled to the shaft at the second end and a cleaning member coupled to and extending peripherally from the head. The cleaning member includes at least one of a scouring pad material formed of intertwined mesh and a compressible porous material. 
     The preceding merely illustrates the principles of the disclosure. It will thus be appreciated that those skilled in the art will be able to devise various arrangements which, although not explicitly described or shown herein, embody the principles of the disclosure and are included within its spirit and scope. For example, in addition to the embodiments recited, the disclosure also covers various other combinations of the disclosed features. For example, the features of one or more of the figures may be combined with features of another figure. In one embodiment, the feature of the lumens shown in  FIGS. 4A and 4B , may be combined with the feature of the winged friction fitting member that includes filter as illustrated in  FIGS. 2D and 2E . Each of the following claims of this document constitutes a separate embodiment, and embodiments that combine different claims and/or different embodiments are within the scope of the disclosure and will be apparent to those of ordinary skill in the art after reviewing this document. 
     Furthermore, all examples and conditional language recited herein are principally intended expressly to be only for pedagogical purposes and to aid the reader in understanding the principles of the disclosure and the concepts contributed to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions. Moreover, all statements herein reciting principles, aspects, and embodiments, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents and equivalents developed in the future, i.e., any elements developed that perform the same function, regardless of structure. 
     This description of the exemplary embodiments is intended to be read in connection with the figures of the accompanying drawing, which are to be considered part of the entire written description. In the description, relative terms such as “lower,” “upper,” “horizontal,” “vertical,” “above,” “below,” “up,” “down,” “top” and “bottom” as well as derivatives thereof (e.g., “horizontally,” “downwardly,” “upwardly,” etc.) should be construed to refer to the orientation as then described or as shown in the drawing under discussion. These relative terms are for convenience of description and do not require that the apparatus be constructed or operated in a particular orientation. Terms concerning attachments, coupling and the like, such as “connected” and “interconnected,” refer to a relationship wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both movable or rigid attachments or relationships, unless expressly described otherwise. 
     Although the disclosure has been described in terms of exemplary embodiments, it is not limited thereto. Rather, the appended claims should be construed broadly, to include other variants and embodiments of the disclosure, which may be made by those skilled in the art without departing from the scope and range of equivalents.