BACKGROUND

Field

[0001] Embodiments described herein generally relate to apparatus and methods used in semiconductor device manufacturing, and more particularly, to apparatus and methods used for the delivery of fluids during chemical mechanical planarization (CMP) of a substrate in an electronic device fabrication process.

Description of the Related Art

[0002] Chemical mechanical polishing (CMP) is commonly used in the manufacture of high-density integrated circuits to planarize or polish a layer of material deposited on a substrate, by contacting the material layer to be planarized with a polishing pad mounted on a polishing platen, and moving one or both of the polishing pad and the substrate (and thus the material layer surface on the substrate) with respect to each other in the presence of a polishing fluid.

[0003] Polishing fluid delivery systems are commonly used in CMP processes to deliver the polishing fluid to the surface of the polishing pad and thus deliver the polishing fluid to an interface between the polishing pad and the material layer surface on the substrate. Typically, the polishing fluid comprises abrasive particles suspended in a suspension fluid and/or reactive agent (i.e. a slurry) where the abrasive particles provide at least a mechanical action against the material layer surface of the substrate to desirably remove material therefrom. Often, delivery lines in the fluid delivery systems become undesirably restricted, and in some cases fully obstructed, by condensed and dried slurry disposed therein, resulting in partial or full obstructions in the polishing fluid delivery lines, inconsistent polishing results, and frequent system maintenance requirements.

[0004] Accordingly, there is a need in the art for apparatus and methods to detect obstructions and restrictions in CMP fluid delivery systems. SUMMARY

[0005] Embodiments of the present disclosure provide for apparatus for detecting the presence of obstruction(s) and restriction(s) in a fluid delivery system used in chemical mechanical polishing (CMP) apparatus and processes and methods of detecting obstruction(s) and restriction(s) in such a fluid delivery system during chemical mechanical polishing (CMP) processes.

[0006] In one embodiment, a fluid delivery apparatus includes a unitary manifold body having an inlet port, a plurality of outlet ports in fluid communication with the inlet port, and a pressure measuring port formed in the unitary manifold body and in fluid communication with at least one of the inlet ports. Herein, the inlet port is in fluid communication with the plurality of outlet ports through a corresponding plurality of fluid delivery conduits extending in or through the unitary manifold body.

[0007] In another embodiment, a fluid delivery apparatus includes a flow splitter manifold having an inlet port and a plurality of outlet ports in fluid communication with the inlet port through a correspond plurality of fluid delivery conduits. The plurality of fluid delivery conduits include a first conduit and a plurality of second conduits fluidly coupled to the first conduit. The fluid delivery apparatus further includes a pressure measuring port in fluid communication with each of the plurality of second conduits and a plurality of outlet fittings respectively disposed in each of the plurality of outlet ports. Each of the plurality of fittings is configured to fluidly couple a respective second conduit to a delivery line. The fluid delivery apparatus further includes a pressure measuring device fluidly coupled to the pressure measuring port.

[0008] In another embodiment, a method of detecting obstruction(s) in a multi- dispense nozzle fluid delivery system used in a chemical mechanical polishing (CMP) system is provided. The method includes flowing a polishing fluid to an inlet port of a flow splitter manifold, measuring a pressure of the polishing fluid disposed in a manifold body of the flow splitter manifold, and dispensing the polishing fluid onto a surface of a polishing pad through a plurality of dispense nozzles. The flow splitter manifold includes the manifold body having an inlet port and a plurality of outlet ports in fluid communication with the inlet port through a plurality of fluid delivery conduits formed in the manifold body, a plurality of outlet fittings respectively disposed in each of the plurality of outlet ports, and a plurality of delivery lines each fluidly coupled to a respective outlet port by one of the plurality of outlet fittings. The flow splitter manifold further includes a pressure measuring device fluidly coupled to a pressure measuring port, wherein the pressure measuring port is in fluid communication with one or more of the plurality of delivery conduits, and wherein the plurality of dispense nozzles are each fluidly coupled to a respective delivery line of the plurality of delivery lines.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this disclosure and are therefore not to be considered limiting of its scope, for the disclosure may admit to other equally effective embodiments.

[0010] Figure 1 A is a schematic sectional view of a polishing system using a multi- dispense nozzle fluid delivery system, according to embodiments described herein.

[0011] Figure 1 B is a schematic view of a dispense nozzle used in the fluid delivery system shown in Figure 1A, according to embodiments described herein.

[0012] Figure 2A is a schematic isometric view of the flow splitter manifold 130 shown in Figure 1A.

[0013] Figure 2B is a cross-sectional view of the manifold body of the flow splitter manifold shown in Figure 1A and 2A taken along line 2B-2B of Figure 2A. [0014] Figure 2C is a cross-sectional view of the manifold body shown in Figures 1A and 2A-2B taken along line 2C-2C of Figure 2A.

[0015] Figure 3 is a flow diagram setting forth a method of detecting obstruction(s) and restriction(s) in a multi-dispense nozzle fluid delivery system, according to embodiments described herein.

[0016] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.

DETAILED DESCRIPTION

[0017] Embodiments of the present disclosure provide for apparatus for detecting obstruction(s) in a fluid delivery system during chemical mechanical polishing (CMP) processes and methods of detecting obstruction(s) and restrictions in such a fluid delivery system during CMP processes. During a conventional CMP process, polishing fluids are dispensed to a location near the center of the polishing pad through a fluid dispense arm positioned thereover. The dispensed polishing fluid is distributed radially outwardly from the dispensed location by the centrifugal force imparted thereto by the rotating polishing pad and along grooves and/or channels formed in the polishing pad. Multi-port dispense arms and/or multi-dispense nozzle distribution systems enable reduced polishing fluid consumption during CMP, when compared to a conventional CMP process, by spacing a plurality of dispense openings and/or dispense nozzles across a radius of the polishing pad and uniformly dispensing the polishing fluid therefrom. In a conventional fluid delivery system, the flowrate of fluid flowing to a single dispense opening/nozzle is typically monitored using a flowmeter and/or flow controller positioned in and/or on a delivery line leading thereto. Obstruction(s) and restrictions in a conventional fluid delivery system are detected by disruptions in the rate of fluid flow to the single monitored dispense opening/nozzle. In a multi-dispense nozzle distribution system measuring and/or monitoring the flowrate in individual delivery lines is costly, impracticable, and in some circumstances disrupts the flow of the polishing fluid flowing therethrough. Therefore, embodiments herein provide a flow splitter manifold, and a pressure measuring device coupled thereto, that enables measuring and monitoring of the pressure of the polishing fluid in the flow splitter manifold. Monitoring the fluid pressure in the flow splitter manifold enables the detection of the presence of an obstruction or restriction in one or more of the delivery lines and dispense nozzles that inhibit or prevent the flow of polishing fluid therethrough or therefrom.

[0018] Figure 1 is a schematic sectional view of an example polishing system using a multi-dispense nozzle fluid delivery system according to embodiments described herein. The polishing system 100 typically includes a polishing platen 102 rotatably disposed about a platen axis 104, a polishing pad 106 mounted on the upper surface of the polishing platen 102, a substrate carrier 108 rotatably disposed about a carrier axis 1 14 and having a substrate holding surface facing the polishing platen 102, a polishing fluid delivery system, such as the multiport polishing fluid delivery system 120 described herein, disposed on a base plate 132, and a polishing pad conditioning apparatus (not shown). Herein, the substrate carrier 108 includes a flexible diaphragm 1 1 1 configured to impose different pressures against different regions of a substrate 1 10 on the substrate holding surface thereof while urging the to be polished surface of the substrate 1 10 against the polishing surface of the polishing pad 106, and a carrier ring 109 surrounding the substrate 1 10.

[0019] During polishing, a downforce on the carrier ring 109 urges the carrier ring 109 against the polishing pad 106 which prevents the substrate 1 10 from slipping from the substrate carrier 108 during the polishing process and deforms the pad to reduce or eliminate polishing edge effects on the substrate edge. The substrate carrier 108 rotates about the carrier axis 1 14 while the flexible diaphragm 1 1 1 urges the to be polished surface of the substrate 1 10 against the polishing surface of the polishing pad 106. The platen 102 rotates about the platen axis 104 in an opposite rotational direction from the rotation direction of the substrate carrier 108. Concurrently, the substrate carrier 108 sweeps back and forth from an inner diameter of the platen 102 to an outer diameter of the platen 102 to, in part, reduce uneven wear of the polishing pad 106.

[0020] During polishing, one or more polishing fluids 1 16 are introduced to the polishing pad 106 using fluid delivery system 120. The fluid delivery system 120 herein is a multi-dispense nozzle fluid delivery system and includes a delivery arm 122 coupled to an actuator 123 that positions the delivery arm 122 above the polishing pad 106 by swinging the delivery arm 122 thereover and/or lowering the delivery arm 122 theretowards. The fluid delivery system 120 further includes a plurality of dispense nozzles 124 disposed on and/or in the delivery arm 122, and a plurality of delivery lines 126 fluidly coupling the dispense nozzles to a flow splitter manifold 130. Typically, the plurality of dispense nozzles 124 includes between about 2 and 20 dispense nozzles, such as between 2 and 15 dispense nozzles, for example between about 2 and 10 dispense nozzles. Herein, the flow splitter manifold 130 is fluidly coupled to a polishing fluid supply 128 and is also secured to a base plate 132 by a support bracket 134. In embodiments herein, the flow splitter manifold 130 is disposed below a horizontal plane of the delivery arm 122 so that the dispense nozzles 124 are disposed above the flow splitter manifold 130 to prevent syphoning of polishing fluid therefrom and to ensure that polishing fluid does not undesirably drain from the flow splitter manifold 130 during periods of non-use. Draining of polishing fluid 1 16 from the flow splitter manifold 130 undesirably contributes to agglomeration of abrasive particles commonly found in polishing fluids by the drying thereof, the coagulation of the polishing fluid by exposure thereof to the oxygen containing atmosphere, and/or condensation of the polishing fluid on the inner surfaces of the fluid delivery system 120.

[0021] Figure 1 B is a close up schematic view of one of the plurality of dispense nozzles 124 shown in Figure 1A. The dispense nozzle 124 is configured for quick change out thereof during routine maintenance and/or after an obstruction or restriction is detected therein. Herein, the dispense nozzle 124 comprises an elongated body having a first end 124a for receiving one of the plurality of delivery lines 126 and a second end 124b for dispensing the polishing fluid 1 16 onto the polishing pad 106. The dispense nozzle 124 is secured to an end of the delivery line 126 by an O-ring 124d disposed about the first end 124a thereof and interferingly received within a corresponding opening in the delivery arm 122. Herein, the plurality of dispense nozzles 124 and the plurality of delivery lines 126 are formed of one or more fluorine-containing polymers (flouropolymers), such as peril uoroalkoxy (PFA), fluorinated ethylene propylene (FEP), or polytetrafluoroethylene (PTFE) commercially available as TEFLON® from DuPont Co., or combinations thereof.

[0022] During CMP processes, the polishing fluid 1 16 flows through an opening 124c formed in the second end 124b of the dispense nozzle 124. The opening 124c has a diameter D(6) that is less than the diameter D(2) of the delivery line 126 creating a backpressure on the polishing fluid disposed in the delivery line 126. Obstructing and restricting of the fluid flow within the dispense nozzle 124 and/or delivery line 126 creates sufficient backpressure in the delivery line 126, and in fluid conduits in communication therewith, to enable detection of a change of fluid pressure in the flow splitter manifold 130 by a pressure measuring device 206 coupled thereto. In some embodiments, a controller 136 is used to monitor the pressure measured by the pressure measuring device 206. In some embodiments, the controller 136 is configured to sound an alarm and/or to stop the polishing process if the measured pressure in the flow splitter manifold 130 is outside of a determined range of the desired fluid pressure.

[0023] Figure 2A is a schematic isometric view of the flow splitter manifold 130 shown in Figure 1A. Herein, the flow splitter manifold 130 includes a manifold body 201 having a top surface 201 a, one or more side surfaces 201 b, a bottom surface 201 c, and one or more recessed surfaces 201 d, where the one or more recessed surfaces 201 d are used to secure the manifold body 201 to the support bracket 134 shown in Figure 1 with one or more fasteners 202. The flow splitter manifold 130 further includes plurality of outlet fittings, such as a plurality of second fittings 205, each disposed in a respective second port 207 (shown in Figure 2B) formed in the top surface 201 a of the manifold body 201. Each of the plurality of second fittings 205 fluidly couple a respective delivery line 126 to a delivery conduit, such as a second conduit 21 1 (shown in Figure 2B) formed in the manifold body 201. Typically, each of the plurality of delivery lines 126 have an inner diameter D(2) between about 1 mm and about 10 mm, such as between about 1 mm and about 5 mm, for example about 3 mm and the inlet line has an inner diameter D(1 ) between about 5 mm and about 20 mm, such as between about 5 mm and about 15 mm, for example about 10 mm.

[0024] The pressure measuring device 206, such as a pressure gauge, is herein coupled to the manifold body 201 using a third fitting (not shown). The fittings described herein are appropriately sized to fluidly couple the respective inlet line, delivery line, or pressure measuring device to fluid conduits disposed in and/or through the manifold body 201 of the flow splitter manifold 130. Typically, the fittings described herein are formed of one or more fluorine-containing polymers (flouropolymers), such as peril uoroalkoxy (PFA), fluorinated ethylene propylene (FEP), or polytetrafluoroethylene (PTFE) commercially available as TEFLON® from DuPont, or combinations thereof. In some embodiments, the fittings described herein are selected from the LQ® High Purity Fluoropolymer series available from SMC Corporation of America of Noblesville, IN. In some embodiments, the fittings described herein are configured to form a face to face seal with the respective fitting port to reduce and/or eliminate dead space therebetween. In some embodiments, the manifold body 201 comprises a unitary body formed of a fluorine-containing polymer.

[0025] During CMP processes, the pressure measuring device 206 and the controller 136 in communication therewith monitor the pressure of the polishing fluid 1 16 disposed in a plurality of fluid delivery conduits, such as a plurality of second conduits 21 1 , through a plurality of pressure measuring conduits, such as a plurality of third conduits 213. Conduits formed in and/or through the manifold body 201 are shown in Figure 2B.

[0026] Figure 2B is a cross-sectional view of the manifold body 201 of the flow splitter manifold 130 shown in Figure 2A taken along line 2B-2B. Typically, the manifold body 201 is formed of a polishing fluid and slurry chemical resistant polymer, such as one or more fluorine-containing polymers (fluoropolymer), such as peril uoroalkoxy (PFA), fluorinated ethylene propylene (FEP), polytetrafluoroethylene (PTFE) commercially available as TEFLON® from DuPont, or combinations thereof. Herein, the manifold body 201 is generally right cylindrically shaped and has a height H(1 ) between about 50 mm and about 100 mm and a diameter D(8) between 20 mm and about 80 mm. In other embodiments the manifold body 201 comprises other suitable shapes.

[0027] Herein, the manifold body 201 includes a plurality of delivery conduits extending in and/or through the material thereof. The plurality of delivery conduits includes at least a first conduit 215 and a plurality of second conduits 21 1. Herein, each of the plurality of second conduits 21 1 are disposed through the manifold body 201 and are fluidly coupled to a first conduit 215. The first conduit 215 has a height H(2) of between about 5 mm and about 20 mm, such as between 10 mm and about 15 mm and diameter D(7) of between about 5mm and about 20 mm, such as between about 5 mm and about 15 mm, for example about 10 mm. The first conduit 215 is fluidly coupled to the inlet line 138 (shown in Figure 2A) using an inlet fitting, such as a first fitting 203 (shown in Figure 2A) that is disposed in a first port 214 formed in the bottom surface 201 c of the manifold body 201. Each of the plurality of second conduits 21 1 are fluidly coupled to a respective delivery line 126 (shown in Figure 2A) using a respective second fitting 205 (shown in Figure 2A) disposed in one of a plurality of second ports 207 formed in the top surface 201 a of the manifold body 201. Herein, each of the plurality of second conduits 21 1 have a length L(1 ) of between about 5 mm and about 50 mm, such as between about 20 mm and about 50 mm, such as between about 30 mm and about 40 mm and diameter D(3) between about 0.5 mm and about 5 mm, such as between about 0.5 mm and about 2.5 mm, for example about 1 mm. Herein, the diameter D(7) of the first conduit 215 is more than the inner diameter D(2) of the to be coupled inlet line 138. In other embodiments, the diameter D(7) of the first conduit 215 is about the same or less than the inner diameter D(7) of the to be coupled inlet line 138.

[0028] The manifold body 201 further includes one or more pressure measuring conduits, such as the plurality of third conduits 213, extending in the material thereof. Herein, each of the plurality of third conduits 213 intersect a respective one of the second conduits 21 1 , and are fluidly coupled thereto, at a location between the first conduit 215 and the respective second port 207. Typically, a length L(2) of each of the third conduits 213 is between about 1 mm and about 30 mm, such as between about 1 mm and about 20 mm, such as between about 1 mm and about 10mm and a diameter D(4) of each of the third conduits 213 is substantially the same as the diameter D(3) of the respective second conduit 21 1 in fluid communication therewith. In other embodiments the diameter D(4) of each of the third conduits 213 is less than or more than the diameter D(3) of a respective second conduit 21 1 and is between about 0.5 mm and about 5 mm, such as between about 0.5 mm and about 2.5 mm, for example about 1 mm.

[0029] Herein the plurality of third conduits 213 are in fluid communication with the third port 210 and the pressure measuring device 206 (shown in Figure 2A) coupled thereto and are fluidly coupled to the pressure measuring device 206 by an appropriately sized third fitting (not shown). In some embodiments, the third port 210 and the third fitting disposed therein define a fluid reservoir 216. Herein, a material forming the manifold body 201 in a region between the first conduit 215 and the third port 210 has a thickness H(3) between about 0.5 mm and about 20 mm, such as between about 0.5 mm and about 5 mm, or for example a thickness necessary to ensure that the first conduit 215 is not in direct fluid communication with the third port 210 or the fluid reservoir 216 thereof. Fluidly coupling the pressure measuring device 206 and/or the fluid reservoir 216 to each of the plurality of second conduits 21 1 , in contrast to a system where the pressure measuring device 206 and/or the fluid reservoir 216 is in direct fluid communication with the first conduit 215, dampens undesirable fluctuation of pressure measurements associated with inherent vibrations of the polishing system 100 during CMP processing.

[0030] In some embodiments, each of a plurality of pressure measuring devices are fluidly coupled to a respective second conduit 21 1 either directly or through a pressure measuring conduit disposed therebetween. In other embodiments, the third port 210 is connected to the first conduit 215 by one or more direct conduits disposed therebetween. In other embodiments, the third port 210 is in direct fluid communication with the first conduit 215. Typically, the ports 214, 207, 210 described herein are sized and/or threaded to receive the respective fittings described herein. In some embodiments, the manifold body further comprises a cavity 209 formed in the top surface 201 a for receiving at least a portion of the pressure measuring device 206 which is coupled directly to the third fitting (not shown).

[0031] Figure 2C is a cross-sectional view of the manifold body 201 shown in Figures 2A-2B taken along line 2C-2C which is orthogonal to line 2B-2B. Herein, the manifold body 201 further includes a purge conduit, such as the fourth conduit 221 , fluidly coupling the third port 210 and/or the fluid reservoir 216 to a fourth port 219 formed in a side surface 201 b of the manifold body 201. In some embodiments, a fitting (not shown) disposed in the fourth port 219 fluidly couples the fourth conduit 221 to a bleed line (not shown) which enables air and/or other fluids trapped in the conduits and/or ports of the manifold body 201 , such as air trapped in the fluid reservoir 216, to be purged therefrom. In some embodiments, air and/or other fluids are purged from the conduits and/or ports of the manifold body 201 by opening a valve (not shown) disposed on the bleed line while simultaneously flowing the polishing fluid 1 16 into the manifold body 201. Once the air and/or other fluids are purged from the manifold body 201 the valve is closed and normal operation of the fluid delivery system 120 may resume. In some embodiments, the valve is coupled to a controller and the manifold body 201 is routinely purged after extended periods of non-use to remove gases accumulated therein. Herein, the fourth conduit 221 has a length L(3) of between about 5 mm and about 50 mm and a diameter D(5) between about 0.5 mm and about 5 mm, such as between about 0.5 mm and about 2.5 mm, for example about 1 mm. Desirably, the valve is located proximate to the manifold body 201 to reduce any undesirable dampening effect on pressure fluctuations in the fluid reservoir 216 associated with the volume of fluid disposed in the bleed line coupled thereto.

[0032] Figure 3 is a flow diagram illustrating a method of detecting obstruction(s) and restriction(s) in a multi-dispense nozzle fluid delivery system, according to embodiments described herein. The method 300 includes flowing a polishing fluid to an inlet port of a flow splitter manifold at activity 310. Herein, the flow splitter manifold comprises a manifold body having an inlet port and a plurality of outlet ports. Each of the plurality of outlet ports are in fluid communication with the inlet port through a plurality of delivery conduits formed in the manifold body. Herein, the flow splitter manifold further comprises a plurality of outlet fittings respectively disposed in each of the plurality of outlet ports, a plurality of delivery lines each fluidly coupled to a respective outlet port by one of the plurality of outlet fittings, and a pressure measuring device fluidly coupled to a pressure measuring port, wherein the pressure measuring port is in fluid communication with the plurality of delivery conduits. Typically, the polishing fluid comprises a polishing slurry flowed to the flow splitter manifold at a flowrate between about 50 ml/min and 1000 ml/min, such as between about 50 ml/min and 500 ml/min.

[0033] The method 300 further includes measuring the pressure of the polishing fluid disposed in the manifold body using the pressure measuring device at activity 320 and flowing the polishing fluid to a surface of a polishing pad through a plurality of dispense nozzles at activity 330, wherein each of the plurality of dispense nozzles are fluidly coupled to a respective delivery line of the plurality of delivery lines. In some embodiments, the method further includes monitoring the measured pressure using a controller coupled to and in communication with the pressure measuring device 206.

[0034] In some embodiments, the controller is configured to sound an alarm and/or to stop the polishing process if the measured pressure is outside of a determined range of the desired fluid pressure. For example, in one embodiment a fluid delivery system comprising six unobstructed dispense nozzles and delivering a combined flowrate of about 300 ml/min of polishing fluid to a polishing pad has a desired fluid pressure, measured in the flow splitter manifold as described in Figures 2A-2C, between about 20 Torr (above atmospheric pressure) and about 40 Torr (above atmospheric pressure), such as about 30 Torr (above atmospheric pressure). When polishing fluid flow to and/or through one of the six dispense nozzles is obstructed the pressure in the flow splitter manifold increases to between about 40 Torr (above atmospheric pressure) and about 60 Torr (above atmospheric pressure) or between about 1.5 times and about 2 times the desired fluid pressure. When polishing fluid flow to and/or through two of the six dispense nozzles is obstructed the pressure in the flow splitter manifold 130 increases to between about 60 Torr (above atmospheric pressure) and about 80 Torr (above atmospheric pressure) or between about 2 times and about 3 times the desired fluid pressure. When the polishing fluid flow to and/or through more than two of the six dispense nozzles is obstructed and/or restricted the pressure increases to more than between about 80 Torr (above atmospheric pressure) and about 100 Torr (above atmospheric pressure), or more than between about 2 times and about 5 times the desired fluid pressure.

[0035] In one embodiment, the controller is configured to sound an alarm and/or to stop the polishing process when the measured pressure indicates that the polishing fluid flowrate to and/or through two or more dispense nozzles are obstructed and/or restricted. In another embodiment, the controller is configured to sound an alarm and/or to stop the polishing process if the measure pressure indicates that the polishing fluid flowrate to and/or through more than two dispense nozzles is obstructed and/or restricted. [0036] In some embodiments, the method 300 further includes determining the delivery line and/or nozzle that has an obstruction or restriction disposed therein. In embodiments where a single pressure measuring device is used to monitor a plurality of dispense nozzles and the delivery lines coupled thereto a user must determine which dispense nozzle(s) and/or delivery line(s) are obstructed and/or restricted. In some embodiments, the location of the obstruction and/or restriction is determined by flowing fluid through the fluid delivery system and visually observing the fluid flow from each of the plurality of dispense nozzles. Typically, once the location of a restriction or obstruction is determined, the restricted or obstructed dispense nozzle(s) and/or delivery line(s) are replaced. In some embodiments the delivery arm, including the plurality of dispense nozzles and the delivery lines coupled thereto, is replaced with a new or refurbished arm in order to reduce equipment downtime related to troubleshooting the location of the restriction or obstruction. In some of those embodiments, the removed delivery arm is later refurbished by replacing and/or cleaning the plurality of dispense nozzles and or the delivery lines coupled thereto as a preventative maintenance procedure.

[0037] The methods and apparatus provided herein enable detection of one or more obstructions or restrictions in the delivery lines and/or dispense nozzles of a multi-nozzle fluid dispense system with sufficient sensitivity to avoid false alarms triggered by unavoidable and inherent vibrations of the polishing system during CMP processing.

[0038] While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.