Surface cleaning with directed high pressure chemicals

Abstract

A cleaning chamber can include a substrate support having a substrate set-down location. The cleaning chamber can include a plurality of fluid nozzles facing the substrate support. Each fluid nozzle of the plurality of fluid nozzles can define a fluid port characterized by a leading edge and a trailing edge. Each fluid nozzle of the plurality of fluid nozzles can be tilted with respect to the substrate set-down location of the substrate support to produce an interior angle greater than or about 90° for fluid delivered from each fluid nozzle at the leading edge of the fluid port at a cross-over location across the substrate set-down location.

Description

[0001] Cross-reference to related applications

[0002] This application claims the benefit and priority of U.S. Nonprovisional Application No. 17 / 541,540, filed December 3, 2021, entitled “SURFACE CLEANING WITH DIRECTEDHIGH PRESSURE CHEMISTRY,” the contents of which are incorporated herein by reference in their entirety for all purposes. Technical Field

[0003] This technology relates to semiconductor systems, processes, and equipment. More specifically, this technology relates to high-voltage substrate cleaning processes and equipment. Background Technology

[0004] Chemical mechanical polishing (CMP) and other processing operations are commonly used in semiconductor manufacturing to planarize or polish layers of material formed on semiconductor substrates. In a typical process, the substrate is pressed against a rotating polishing pad, and a polishing slurry flows across the pad. Material formed along the substrate is removed through a combination of chemical interactions of the polishing slurry and mechanical interactions with the polishing pad. Substrate cleaning during manufacturing may be insufficient as particle incorporation becomes a greater challenge for the further development of CMP and other processes.

[0005] Therefore, there is a need for improved systems and methods that can be used to enhance systems for cleaning and increasing particle removal. This technology addresses these and other needs. Summary of the Invention

[0006] The cleaning chamber may include a substrate support having a substrate mounting location. The cleaning chamber may include a plurality of fluid nozzles facing the substrate support. Each of the plurality of fluid nozzles may define a fluid port characterized by a leading edge and a trailing edge. Each of the plurality of fluid nozzles may be tilted relative to the substrate mounting location of the substrate support to create an interior angle greater than or approximately 90° at an intersection of the fluid delivered from each fluid nozzle at the leading edge of the fluid port across the substrate mounting location.

[0007] In some embodiments, each fluid nozzle is operable to deliver fluid at greater than or about 500 psi. The plurality of fluid nozzles can be a first plurality of fluid nozzles, and the cleaning chamber can include a second plurality of fluid nozzles. The first plurality of fluid nozzles can be directed in a first direction toward the substrate set position. The second plurality of fluid nozzles can be directed in a second direction opposite the first direction toward the substrate set position. Each fluid nozzle of the first plurality of fluid nozzles can be separated from each adjacent fluid nozzle of the first plurality of fluid nozzles by a gap. Each fluid nozzle of the second plurality of fluid nozzles can be positioned in alignment with a gap between two fluid nozzles of the first plurality of fluid nozzles. Each fluid nozzle of the first plurality of fluid nozzles can be disposed along a line in a first direction across the cleaning chamber. Each fluid nozzle of the second plurality of fluid nozzles can be disposed along a line in a second direction across the cleaning chamber perpendicular to the first direction. The cleaning chamber or system can include a first cleaning fluid reservoir fluidly coupled with the first plurality of fluid nozzles within the cleaning chamber. The cleaning chamber or system can include a second cleaning fluid reservoir fluidly coupled with the second plurality of fluid nozzles within the cleaning chamber. The first cleaning fluid reservoir can include a first cleaning fluid, and the second cleaning fluid reservoir can include a second cleaning fluid different from the first cleaning fluid. Each fluid port can be characterized by a slit opening.

[0008] Some embodiments of the present technology can encompass a method of substrate cleaning. The method can include positioning a substrate in a substrate cleaning chamber. The method can include spraying a cleaning fluid at the substrate from a plurality of fluid nozzles within the substrate cleaning chamber, wherein each fluid nozzle of the plurality of fluid nozzles is tilted relative to the substrate such that an interior angle between the cleaning fluid and a leading edge of delivery from each fluid nozzle is greater than or about 90°.

[0009] In some embodiments, the method can include rotating the substrate within the substrate cleaning chamber while spraying the cleaning fluid. The cleaning fluid can be sprayed at a fluid pressure less than or about 250 psi. The method can include reversing a direction of rotation. The method can include continuing to spray the cleaning fluid at the substrate. The cleaning fluid can be sprayed at a fluid pressure greater than or about 500 psi. The cleaning fluid can be or include deionized water, hydrofluoric acid, or ammonium hydroxide. The cleaning fluid can include a first cleaning fluid, and the method can include pausing spraying of the first cleaning fluid. The method can include spraying a second cleaning fluid at the substrate. The plurality of fluid nozzles can be a first plurality of fluid nozzles, and the second cleaning fluid can be sprayed from a second plurality of fluid nozzles. Each fluid nozzle of the first plurality of fluid nozzles can be disposed along a line in a first direction across the substrate cleaning chamber. Each fluid nozzle of the second plurality of fluid nozzles can be disposed along a line in a second direction across the substrate cleaning chamber perpendicular to the first direction.

[0010] Some embodiments of the present technology can encompass a cleaning chamber. The cleaning chamber can include a substrate support including a substrate mounting location. The cleaning chamber can include a plurality of fluid nozzles facing the substrate support. Each fluid nozzle of the plurality of fluid nozzles can define a fluid port characterized by a jet angle having a jet leading edge and a jet trailing edge. Each fluid nozzle of the plurality of fluid nozzles can be tilted relative to the substrate mounting location of the substrate support such that the jet leading edge of the jet angle of the fluid port of each fluid nozzle of the plurality of fluid nozzles intersects a location across the substrate mounting location at an interior angle greater than or about 90°. In some embodiments, the substrate support can include a rotatable drum. The plurality of fluid nozzles can be coupled outside the rotatable drum along a sidewall of the cleaning chamber. Each fluid nozzle can be operable to deliver fluid at greater than or about 500 psi.

[0011] Such technology can provide significant benefits over conventional systems and techniques. For example, the cleaning system can allow for cost effective processing that can rapidly reduce particle contamination across a plurality of substrate surfaces. Additionally, the present technology can reduce particle counts on any number of substrates that can be processed in several ways. These and other embodiments, along with many of their advantages and features, are described in more detail in conjunction with the below description and attached figures. BRIEF DESCRIPTION OF DRAWINGS

[0012] A further understanding of the nature and advantages of the disclosed technology can be realized by reference to the remaining portions of the specification and the attached drawings.

[0013] Figure 1 A schematic cross-sectional view of an exemplary processing system is shown, in accordance with some embodiments of the present technology.

[0014] Figure 2 Selected operations in a processing method are shown, in accordance with some embodiments of the present technology.

[0015] Figure 3 A schematic cross-sectional view of an exemplary cleaning system is shown, in accordance with some embodiments of the present technology.

[0016] Figure 4 A schematic view of an exemplary cleaning nozzle arrangement is shown, in accordance with some embodiments of the present technology.

[0017] Figure 5 A schematic view of an exemplary nozzle tilt angle is shown, in accordance with some embodiments of the present technology.

[0018] Figure 6 A schematic view of an exemplary nozzle orientation is shown, in accordance with some embodiments of the present technology.

[0019] Figure 7 A schematic view of an exemplary nozzle orientation is shown, in accordance with some embodiments of the present technology.

[0020] Figure 8 A schematic diagram showing exemplary nozzle orientations in accordance with some embodiments of the present technology.

[0021] Figure 9 A schematic diagram showing exemplary nozzle orientations in accordance with some embodiments of the present technology.

[0022] Several of the drawings in the attached Figures are included as schematic representations. It should be understood that the Figures are presented for illustrative purposes and should not be viewed as being proportionally representative of any actual structure. Additionally, as a schematic representation, the Figures are provided to aid understanding and can not include all aspects or information as compared to a realistic representation, and can include exaggerated materials for illustrative purposes.

[0023] In the drawings, like reference numerals can be used to denote similar components and / or features throughout the several views. Additionally, various components of the same type can be distinguished from one another by adding a letter suffix, e.g., 102a, 102b, etc. to one another. If the first reference numeral is used only once to refer to a component, then the description is applicable to each like component bearing the same first reference numeral and letter suffix, regardless of the letter suffix. DETAILED DESCRIPTION

[0024] Substrate processing can involve formation and removal of materials to produce any number of structures. During processing, particle generation and contamination can impact interface layer compatibility and layer formation quality. Chemical mechanical polishing or any other type of polishing or removal can be performed to produce a relatively flat surface, such as within system tolerances, although the operation can introduce any number of particles. A brush scrubber can be used to remove residual material from the polishing operation, although conventional brush scrubbing can be limited in the size of particles that can be removed, and can also introduce additional particulate material from the scrubber. Brush scrubbing also faces the limitation that the brush becomes a consumable, thereby having variable cleaning efficiency over the brush useful life, and requiring tool down time for replacement at the end of life. Thus, particle contamination can continue to be an obstacle to further expansion of any number of semiconductor, solar, or display manufacturing processes.

[0025] Other conventional cleaning systems can similarly suffer from inadequate cleaning. For example, spray cleaning in conventional techniques is typically performed at low pressures, with the spray nozzles oriented directly in line with the substrate to be cleaned. Lower pressures are used to limit any impact on device features, which can otherwise cause pattern collapse. However, this can create a number of problems for substrate cleaning. For example, low pressures can allow certain large particles to be removed from the substrate, but can not have enough force to remove smaller particulate matter. Additionally, spray nozzles oriented directly perpendicular to the substrate surface to be cleaned can introduce several challenges. In addition to requiring longer cleaning times, the interaction of the fluid pattern on the substrate from the adjacent nozzles can cause vortices to form between the fluid streams from the interaction of adjacent nozzles. While large particles can be removed, the interaction can reduce the force of the fluid flow, which can not be able to overcome the van der Waals forces between the substrate and smaller particles, or can allow smaller particles to re-attach at secondary locations due to the vortices formed across the substrate being cleaned. Thus, conventional techniques have been unable to improve substrate cleaning and particle removal.

[0026] The present technology overcomes these problems with conventional scrubbing and cleaning systems by providing a cleaning system with nozzles angled in a particular manner to create a fluid flow pattern that can increase particle removal and reduce nozzle interaction. Additionally, the present technology can utilize increased fluid pressure, which can improve particle removal across the surface to be cleaned. The present technology can utilize one or more fluids to adjust the zeta potential between the cleaning fluid and the particles across the substrate surface, which can alter the particle and substrate charge to facilitate removal and easily overcome van der Waals forces between the particles and the substrate surface at the primary location and during transport from the substrate.

[0027] While the remainder of the disclosure will routinely identify particular semiconductor processes in which the disclosed technology is utilized, it will be readily understood that the systems and methods are equally applicable to a variety of other substrates to be cleaned, including display panels, solar panels, or any other substrate in which particle removal can be beneficial. Thus, the present technology should not be considered limited to use solely with the substrates and processes described. Prior to describing the operation of systems and methods, or exemplary process sequences, in accordance with some embodiments of the present technology, the present disclosure will discuss one possible system that can be utilized with the present technology. It should be understood that the present technology is not limited to the described equipment, and the processes discussed can be performed in any number of processing chambers and systems, some modifications of which will be explained below.

[0028] Figure 1A schematic cross-sectional view of an exemplary polishing system 100 according to some embodiments of the present technology is shown. The polishing system 100 includes a platen assembly 102, which includes a lower platen 104 and an upper platen 106. The lower platen 104 can define an interior volume or cavity through which connections can be made, and in which endpoint detection equipment or other sensors or devices, such as eddy current sensors, optical sensors, or other components for monitoring polishing operations or components, can be included. For example, and as described further below, fluid couplings can be made with wiring that extends through the lower platen 104, and the wiring can pass into and out of the upper platen 106 via a backside of the upper platen. The platen assembly 102 can include a polishing pad 110 mounted on a first surface of the upper platen. A substrate carrier 108 or carrier head can be disposed above and can face the polishing pad 110. The platen assembly 102 can be rotatable about an axis A, while the substrate carrier 108 can be rotatable about an axis B. The substrate carrier can also be configured to sweep back and forth along the platen assembly from an inner radius to an outer radius, which can partially reduce uneven wear of a surface of the polishing pad 110. The polishing system 100 can also include a fluid delivery arm 118 positioned above the polishing pad 110, and the fluid delivery arm 118 can be used to deliver a polishing fluid, such as a polishing slurry, onto the polishing pad 110. Additionally, a pad conditioning assembly 120 can be disposed above and can face the polishing pad 110.

[0029] In some embodiments in which a chemical mechanical polishing process is performed, a rotating and / or sweeping substrate carrier 108 can exert a downforce on a substrate 112, which is shown in dashed lines and can be disposed within or coupled with the substrate carrier. As the polishing pad 110 rotates about a central axis of the platen assembly, the applied downforce can press a material surface of the substrate 112 against the polishing pad 110. The interaction of the substrate 112 with the polishing pad 110 can occur in the presence of one or more polishing fluids delivered by the fluid delivery arm 118. A typical polishing fluid can include a slurry formed from an aqueous solution in which abrasive particles can be suspended. Often, the polishing fluid contains pH adjusters and other chemically active components, such as oxidizing agents, which can enable chemical mechanical polishing of the material surface of the substrate 112.

[0030] The backing pad conditioning assembly 120 is operable to apply a fixed abrasive conditioning disk 122 against a surface of the polishing pad 110, which can be rotating as previously described. The conditioning disk can be operated against the backing pad before, after, or during polishing of the substrate 112. Conditioning the polishing pad 110 with the conditioning disk 122 can maintain the polishing pad 110 in a desired condition by abrading, regenerating, and removing polishing byproducts and other debris from the polishing surface of the polishing pad 110. The upper platen 106 can be disposed on a mounting surface of the lower platen 104 and can be coupled with the lower platen 104 using a plurality of fasteners 138, such as annular flange-shaped portions extending through the lower platen 104.

[0031] The polishing platen assembly 102, and thus the upper platen 106, can be suitably dimensioned for any desired polishing system and can be dimensioned for any diameter of substrate, including 200 mm, 300 mm, 450 mm, or larger. For example, a polishing platen assembly configured to polish a 300 mm diameter substrate can be characterized by a diameter greater than about 300 mm, such as between about 500 mm and about 1000 mm, or greater than about 500 mm. The diameter of the platen can be adjusted to accommodate substrates characterized by larger or smaller diameters, or for polishing platens 106 dimensioned for simultaneous polishing of multiple substrates. The upper platen 106 can be characterized by a thickness between about 20 mm and about 150 mm, and can be characterized by a thickness less than or about 100 mm, such as less than or about 80 mm, less than or about 60 mm, less than or about 40 mm, or smaller. In some embodiments, the ratio of the diameter to the thickness of the polishing platen 106 can be greater than or about 3: 1, greater than or about 5: 1, greater than or about 10: 1, greater than or about 15: 1, greater than or about 20: 1, greater than or about 25: 1, greater than or about 30: 1, greater than or about 40: 1, greater than or about 50: 1, or larger.

[0032] The upper and / or lower platens can be formed of a suitably rigid, lightweight, and resistant to corrosion by polishing fluids material, such as aluminum, an aluminum alloy, or stainless steel, although any number of materials can be used. The polishing pad can be formed of any number of materials, including polymeric materials, such as polyurethane, polycarbonate, fluoropolymers, polytetrafluoroethylene polyphenylene sulfide, or combinations of any of these or other materials. Additional materials can be or include open- or closed-cell foam polymers, elastomers, felts, impregnated felts, plastics, or any other materials that can be compatible with the process chemicals. It will be understood that the polishing system 100 is included to provide suitable reference to components that can be incorporated into the system 100 discussed below, although the description of the polishing system 100 is not intended to limit the technology in any way, as embodiments of the technology can be incorporated into any number of polishing systems that can benefit from the components and / or capabilities as further described below.

[0033] A polishing assembly as described above and in accordance with embodiments of the present technology can be used in a substrate cleaning method in accordance with some embodiments of the present technology. Polishing operations can introduce any number of particles, including from the slurry, the mounting surface, and the polishing pad. As explained above, chemical mechanical polishing can not necessarily be performed prior to performing a substrate cleaning operation in accordance with some embodiments of the present technology, which can be the case for many substrate cleaning processes. However, particles resulting from polishing or other operations can leave a variety of sizes of particles along the various surfaces of the substrate. Figure 2 Selected operations in a method 200 of substrate cleaning in accordance with some embodiments of the present technology are shown. The method 200 can include one or more operations prior to the start of the method operations, including processing for developing one or more material layers on a semiconductor, display, or other substrate, and any number of processes for removing or developing features on the substrate. The processes can develop particulate matter that can be exposed on the substrate and in some embodiments attached to the backside of the substrate.

[0034] Some embodiments can optionally include a process that performs a chemical mechanical polishing process at optional operation 205, and the process can provide a substantially planar surface across the substrate, but it should be understood that the planar surface to be cleaned can be provided by any number of methods. Planarity means a relatively flat surface, such as within the tolerances of the process used to produce the planarity, for example including chemical mechanical polishing. Additionally, in some embodiments, the exposed surface of the substrate can be characterized by any number of topographies, which can result from any processing or manufacturing method. At operation 210, the method 200 can include positioning the substrate within a cleaning chamber, which can include a substrate support including a substrate seating location. An exemplary cleaning chamber can be described in more detail below.

[0035] At operation 215, the method 200 can include spraying a cleaning fluid across the substrate. The fluid can be delivered from a plurality of nozzles that can extend across one or more portions of the chamber. As will be described in greater detail below, the fluid nozzles according to some embodiments of the present technology can be tilted with respect to the substrate surface, which can improve the cleaning process. In some embodiments, the substrate can be rotated within the cleaning chamber with respect to the nozzles, or otherwise translated in one or more directions at optional operation 220 to improve surface cleaning. Depending on the direction of rotation, the concepts of leading and trailing edges can be reversed from what is described, and it should be understood that in some embodiments, depending on the direction of rotation with respect to the tilt angle of the fluid nozzles, either edge can be the leading or trailing edge. Additionally, the fluid nozzles can be translated laterally within the chamber to further improve substrate surface cleaning and exposure, such as by moving the span from which the fluid nozzles extend. In some embodiments, the spraying operation with a first cleaning fluid can be paused, and a second cleaning fluid can be sprayed or otherwise delivered at optional operation 225, and the second cleaning fluid can be delivered from the same or different fluid nozzles within the processing chamber. Any number of additional fluid deliveries can also be performed. Aspects of the cleaning method 200 can be performed to improve cleaning and processing yields, and will be described in detail below. It should be understood that any of the aspects described below can be applied in the method 200 or any other cleaning method utilizing aspects of the present technology.

[0036] Figure 3 A schematic cross-sectional view of an exemplary cleaning system 300 according to some embodiments of the present technology is shown, although processes according to embodiments of the present technology can be performed in a variety of chambers and systems. The cleaning system 300 illustrates an exemplary system in which a substrate can be cleaned along one or more surfaces when positioned in a vertical orientation, facilitating gravity removal of fluid being delivered. It should be understood that a variety of adjustments can be made to the system in embodiments, including having chambers in which the substrate is positioned horizontally and / or clamped onto a substrate support. Methods according to some embodiments of the present technology, including the method 200, can be performed in the system 300 or an alternative system having one or more of the components discussed throughout this application. It should be understood that the cleaning system 300 is not shown in any particular scale, and is only shown to illustrate components that can be included in some embodiments. It should be understood that components can be spaced closer or further apart from one another to provide effects or scaling as discussed throughout this disclosure.

[0037] Cleaning system 300 can include a chamber body 305, which can allow for vertical orientation of a substrate within the chamber, although in some embodiments, the chamber can be oriented with wafers placed horizontally, with fluid delivery from above and / or below. In some embodiments, the chamber body can include a roller 310 disposed within the chamber body 305, and the roller 310 can include or define a substrate seat 312, allowing for disposition or seating of a substrate 315 within the cleaning chamber. In some embodiments, the roller 310 can be rotatable within the chamber body 305, which can facilitate cleaning operations as previously described, and which can allow for stable fluid delivery while rotating the substrate. The substrate 315 can be characterized by any of the previously described dimensions, and can also include rectangular dimensions, such as for display, solar, or other panel substrate configurations.

[0038] Depending on the substrate and cleaning operation, the roller 310 can define substrate placement to allow for exposure of the substrate along opposing surfaces, which can allow for simultaneous cleaning of processed surfaces or surfaces on which formation or removal has occurred, as well as backside surfaces, according to some embodiments of the present technology. Additionally, in some embodiments of the present technology, the roller or substrate support can include a substrate seating surface, which can allow for clamping of the substrate, such as with vacuum or electrostatic clamping. When configured for rotation, the roller 310 or substrate support can be operable to rotate at any speed, including speeds accommodating cleaning operations and spin or drying operations. Additionally, the roller 310 can be rotatable about an axis allowing for an elliptical path, and the axis can provide lateral movement and rotational movement to improve cleaning exposure on the substrate.

[0039] Cleaning system 300 can also include a fluid delivery device 320, and in some embodiments of the present technology can include a second fluid delivery device 325. As will be described below, the fluid delivery device 320 or 325 can include a plurality of fluid nozzles, and the plurality of fluid nozzles can deliver or jet one or more cleaning fluids across a substrate. The fluid delivery device 320 can be fluidically coupled with a first fluid reservoir 322, which can deliver one or more fluids to one or more of the plurality of nozzles of the fluid delivery device 320. Similarly, the fluid delivery device 325 can be fluidically coupled with a second fluid reservoir 327, which can deliver one or more fluids to one or more of the plurality of nozzles of the fluid delivery device 320. As will be described below, the fluid nozzles can be distributed in one or more patterns within the chamber body 305, and can or can not be translatable in embodiments of the present technology. For example, in some embodiments, the fluid nozzles can extend from a ledge that can be rotatable or laterally translatable, although in some embodiments, the nozzles or ledge can be fixed within the chamber body, which can limit additional particle generation from moving parts within the cleaning chamber.

[0040] Figure 4 A schematic diagram illustrating an exemplary cleaning nozzle arrangement 400 according to some embodiments of the present technology is shown, and can illustrate details of a fluid delivery apparatus as previously described. A substrate 405 is included, and can be any substrate to be cleaned, and can be disposed, positioned, or housed within a cleaning chamber incorporating one or more cleaning nozzle arrangements 400. Although illustrated in a vertical orientation, it should be understood that in embodiments encompassed by the present technology, the system can be disposed horizontally. Additionally, although the nozzles are illustrated in a vertical orientation, the nozzles can also be disposed on horizontal ledges across the chamber, and can be illustrated without a particular orientation or direction. Similarly, for embodiments in which the substrate can be rotated, the figure can illustrate a configuration and / or nozzle orientation in which the substrate 405 can be rotated in a direction into or out of the page. The cleaning nozzles can be included in a cleaning system as discussed above or any other cleaning system, and can be used to perform a cleaning process as previously discussed. The present technology can provide a cleaning nozzle setup with nozzles at a particular angle, allowing for improved flow and cleaning across the substrate, and this can limit vortex formation or interference across the substrate. As shown, the arrangement can include a ledge 410 or bridge, which can be coupled with a fluid reservoir as discussed above, and can include one or more channels along or within the ledge for fluid delivery to one or more fluid nozzles 415.

[0041] The fluid nozzles 415 can extend from the ledge 410 at an angle 417, and can face the substrate. The nozzles can extend to direct the nozzles to be oriented away from normal position relative to the substrate 405. Any number of fluid nozzles can be disposed along the ledge, and the fluid nozzles can be spaced apart to include any gap 419 between the fluid nozzles. Additionally, the number of fluid nozzles included can depend on the size and shape of the substrate to be cleaned. Each fluid nozzle can define or include a fluid port 420, which can define a fluid spray 425 to the substrate. Although the fluid port 420 can be an aperture or circular shape, in some embodiments the fluid port 420 can define a slit or slot, such as a rectangular opening, and can provide a flat fluid spray 425 to the substrate. Any number of aperture or fluid port designs are encompassed by the present technology, and can be used to adjust fluid spray pressure and distribution as fluid is delivered to the substrate.

[0042] As will be further explained below, in some embodiments, the fluid nozzles can be tilted to provide a particular spray distribution along the surface of the substrate. For example, the fluid ports can define a pattern of fluid spray 425, including a spray angle 427, which can also be influenced by the pressure at which the cleaning fluid can be delivered through the system. While the present technology can encompass any spray angle 427, the fluid nozzles 415 according to some embodiments can provide a spray angle of less than or about 60°, and can provide a spray angle of less than or about 55°, less than or about 50°, less than or about 45°, less than or about 40°, less than or about 35°, less than or about 30°, less than or about 25°, less than or about 20°, less than or about 15°, less than or about 10°, or less. In some embodiments, the spray angle provided is greater than or about 10°, greater than or about 15°, or greater, which can reduce the number of nozzles used to provide coverage across the substrate surface. By maintaining a relatively small spray angle, the force across the plate corresponding to the spray can be more uniform for a tilted pattern, which can improve cleaning efficiency in the systems encompassed. In some embodiments, the angle 417 can be similar to the spray angle, or can be a portion (such as half) of the spray angle added in one direction from the normal orientation, as will be further described below, which can align the nozzles to direct the leading edge of the fluid spray.

[0043] The orientation of the nozzles and the spray angle of the delivered spray can influence the impact pattern across the substrate. The present technology can orient the nozzles to provide a spray pattern configured to limit or prevent interaction between fluid sprays from adjacent nozzles by limiting countervailing flow between the nozzles. Figure 5 A schematic diagram showing an example nozzle tilt angle according to some embodiments of the present technology is shown, and can illustrate additional details of aspects of the cleaning nozzle arrangements described above. Again, while shown in a horizontal orientation, aspects can be encompassed in any orientation by the figure. Additionally, for embodiments in which the substrate can be rotated, the figure can illustrate configurations and / or nozzle orientations in which the substrate can be rotated in a direction into or out of the page. As discussed above, each fluid nozzle can provide a spray pattern 425 characterized by a spray angle. The fluid port 420 and / or fluid spray 425 can be characterized by a leading edge 505 and a trailing edge 510 of the fluid spray delivery toward the substrate, the leading edge 505 can be characterized by a shorter distance from the substrate, and the trailing edge 510 can be characterized by a longer distance from the substrate. In some embodiments of the present technology, each fluid nozzle can be tilted relative to the substrate 405 or the position of the substrate within the corresponding cleaning chamber to create an interior angle 515 at the leading edge that is greater than or about 90°. For example, as shown, each nozzle is tilted such that the interior angle 515 is 90° at the intersection between the fluid port or leading edge of the delivered fluid and the position at which the fluid contacts the substrate across the leading edge of the substrate 405.

[0044] When a fluid nozzle is positioned perpendicular, without an angle, or directly facing the substrate surface, the fluid spray will contact the substrate and spread in every direction, such as in opposite lateral directions, or in all directions around a cone. Adjacent fluid nozzles with similar orientations will counteract the flow from the first nozzle, which can reduce the forces between the streams and develop eddies across the substrate, and possibly flow stagnation at certain locations. Because particles can have an attraction to the surface, such as van der Waals forces, stagnation can prevent particles from being dislodged. Additionally, for particles that can have been initially dislodged, flow extending to an eddy location or another stagnation point can allow the particles to be re-attracted to the surface, and the attraction can be sufficient to re-secure the particles. The present technology provides tilted fluid nozzles and delivers fluid in a controlled pattern to limit or prevent interfering flows between nozzles, which can ensure more similar flow and flow forces across the substrate. This can facilitate dislodging particles from the substrate, and can maintain sufficient forces in the flow pattern to ensure complete removal of particles from the surface.

[0045] While some amount of impinging flow can result in some degree of interaction between fluid streams, the increased force at the leading edge can overcome the counter flow at the trailing edge of the stream that has been reduced, and this can limit any impact on the flow pattern, particularly in terms of fluid pressure, as will be discussed below. Due to tolerances in both flow and mounting, the angles can overlap by less than or about 2° to limit interaction, although in embodiments the angle at the leading edge relative to the substrate can necessarily be greater than or about 85°, and can be greater than or about 88°, greater than or about 89°, greater than or about 90°, greater than or about 92°, greater than or about 94°, greater than or about 96°, greater than or about 98°, greater than or about 100°, greater than or about 105°, greater than or about 110°, greater than or about 115°, greater than or about 120°, or more.

[0046] The outer angle 520 at the trailing edge can also be controlled by the distance the nozzle is disposed from the substrate. In some embodiments, the outer angle 520 can be controlled to be less than or about 160°, and can be maintained at less than or about 155°, less than or about 150°, less than or about 145°, less than or about 140°, less than or about 135°, less than or about 130°, less than or about 125°, less than or about 120°, less than or about 115°, less than or about 110°, less than or about 105°, less than or about 100°, or less. By controlling the distance from the substrate and maintaining a lower outer angle, the force exerted at the trailing edge can be closer to the force exerted at the leading edge, which can provide more uniform cleaning in some embodiments of the present technology.

[0047] To facilitate particle removal on the substrate, in some embodiments, the cleaning fluid can be delivered from each fluid nozzle at a pressure greater than or about 200 psi, and can be delivered at a pressure greater than or about 250 psi, greater than or about 300 psi, greater than or about 350 psi, greater than or about 400 psi, greater than or about 450 psi, greater than or about 500 psi, greater than or about 550 psi, greater than or about 600 psi, greater than or about 650 psi, greater than or about 700 psi, or greater. In embodiments in which a chemical mechanical polishing process has been performed previously or in which a substantially planar surface has otherwise been formed, the pressure can be maintained at greater than or about 500 psi. Higher pressures can result in damage or pattern collapse where numerous features are formed across the substrate. However, some embodiments of the present technology can be performed particularly on substrates characterized by a profile that is substantially planar (within tolerances of previous operations). This can allow for increased fluid pressure, which can further reduce and remove particles from contaminating the surface of the substrate. Additionally, in some embodiments, a first surface can be cleaned by delivering fluid at a first fluid pressure, and a second surface opposite the first surface can be cleaned by delivering fluid at a second fluid pressure different from the first fluid pressure, which can account for different topography or materials exposed across the surface.

[0048] Fluids used as cleaning fluids according to some embodiments of the present technology can include any fluid or etchant material that can be jetted as previously described. For example, the cleaning fluid can include deionized water, an acidic fluid such as hydrofluoric acid, a basic fluid such as ammonium hydroxide, or any other material as would be appreciated by the skilled person. In some embodiments, an acid or base solution can be diluted to limit the impact on the structure being cleaned. For example, hydrofluoric acid can be diluted with deionized water to less than or about 500: 1, less than or about 700: 1, less than or about 800: 1, less than or about 900: 1, or less than or about 1000: 1, which can reduce the amount of etching that can occur against materials or features exposed across the substrate.

[0049] Any of these materials can be delivered alone or in some combination to perform a cleaning process. As one non-limiting example, a higher pressure deionized water spray can be delivered to initially clean larger particles from the substrate for a first time period. An acidic or basic fluid can then be delivered at the same or different pressure for a second time period, which can facilitate removal of smaller particles. A subsequent deionized water spray and drying operation can then be performed to remove the acid or base material and clean the substrate. The present technology similarly encompasses any other combination or sequence. By utilizing different materials, removal can be further tuned to affect zeta potential, which can adjust the charge of the particles across the substrate and the surface charge of the substrate itself. By utilizing different fluids characterized by different potentials, the particle charge can be adjusted closer to the surface charge, and the attractive force can be reduced, or it can be more likely to repel particles from the surface, which can further improve removal of small particles.

[0050] According to some embodiments of the present technology, the present technology can also include additional aspects regarding nozzles and fluid delivery, which can further improve cleaning or reduce cleaning time. Figure 6 A schematic diagram showing an exemplary nozzle orientation 600 according to some embodiments of the present technology is shown. As shown, a crossbar 605 having a plurality of nozzles can be shown with respect to an exemplary or conceptual substrate 610. As shown, in some embodiments of the present technology, nozzles according to some embodiments of the present technology can be tilted in a second direction as well as a first direction. For example, fluid nozzles can be tilted along the crossbar 605 along direction 615, which can illustrate a fluid nozzle tilt angle with respect to a substrate surface as previously described.

[0051] Additionally, the fluid nozzles may be tilted along the crossbar 605 in direction 620, which can guide fluid with or against the rotating substrate. Direction 620 can be generated by tilting the fluid nozzles at any of the previously described angles, including any orientation angle such as angle 417 discussed above. Although direction 620 is illustrated as a straight-line orientation, it should be understood that each arrow can be further oriented in the direction as previously described, which, as will be readily apparent to those skilled in the art, provides two orientation angles. Additionally, embodiments including a first plurality of fluid nozzles oriented in direction 620 and a second plurality of fluid nozzles oriented in the opposite direction 622 are illustrated. Around the midpoint of crossbar 605, in some embodiments, the nozzle orientation can be reversed as shown, which ensures continuous flow across the substrate of the rotating substrate, although this arrangement can also be used in other systems that may not involve rotation of the substrate. Direction 620 and the opposite direction 622 are illustrated as tilted perpendicular to crossbar 605, but it should be understood that the nozzle angles can also deviate from the normal and can be tilted from the crossbar in multiple directions, as well as along the crossbar as discussed above. For example, the nozzle can be tilted along direction 621, which can deviate from the normal and can be tilted to any degree and away from the crossbar in any direction, which can further adjust particle removal and flow characteristics across the substrate.

[0052] As shown, substrate 610 can rotate in either direction. When rotating in direction 625, the fluid spray along direction 620 can have a reduced effect on the substrate because the fluid spray will be delivered in a direction complementary to the rotation. Conversely, when the substrate rotates in direction 630, the fluid spray along direction 630 can have a greater effect on the substrate because the fluid spray will be delivered in the opposite direction to the rotation. Depending on the fluid pressure, the amount of force required to remove material and particles exposed on the substrate, the rotation of the substrate, and the nozzle tilt angle can all facilitate cleaning and control the fluid flow across the substrate. Furthermore, in some embodiments, the angle of the fluid nozzles can be varied based on the position of the fluid nozzles relative to local locations on the substrate. For example, in some embodiments, each fluid nozzle extending outward from the center can be tilted along an increasing or decreasing tilt gradient and can include nozzles tilted in any direction within any of the previously discussed angle ranges. This allows for additional control of fluid flow based on the difference in angular momentum between locations closer to the outer edge of the substrate and locations closer to the center of the substrate.

[0053] Figure 7 A schematic diagram illustrating exemplary nozzle orientation according to some embodiments of the present technology is shown, and a configuration incorporating a first plurality of fluid nozzles 705 and a second plurality of fluid nozzles 710 is illustrated, both shown as directions in which fluid delivery may occur, such as along a second angle, and this may be combined with a first angle as previously described. As previously stated in Figure 4As shown in the middle, depending on the angle or orientation, fluid pressure, and gap distance between the nozzles, the fluid pressure across the substrate surface can be more or less uniform. Figure 7 A configuration is shown in which each fluid nozzle is separated from an adjacent fluid nozzle by a gap. A second fluid line can be disposed through the crosspiece, and the second fluid line can deliver the same or different cleaning fluid, and can deliver fluid via a second plurality of fluid nozzles 710. Each nozzle in the second plurality of fluid nozzles can be positioned in alignment with a gap between two fluid nozzles in the first plurality of fluid nozzles 705. This can allow for more uniform force across the substrate surface, while limiting interaction between fluid sprays. The pressure between the two pluralities of nozzles can be similar or different, which can account for spatial aspects to limit or prevent interference between flows, while maximizing particle removal across the substrate surface. By also orienting the nozzles in the same oblique direction, such as the second angle discussed above, the flows can have limited or no overlap between the first plurality of fluid nozzles and the second plurality of fluid nozzles.

[0054] Additionally, in some embodiments, the first plurality of fluid nozzles and the second plurality of fluid nozzles can be oriented along the same first angle as discussed above, or the first plurality of fluid nozzles can be oriented in a first direction across the substrate, and the second plurality of fluid nozzles can be positioned in an opposite direction across the substrate. Additionally, in some embodiments, the first plurality of fluid nozzles can be used to perform cleaning with a first fluid, and the second plurality of fluid nozzles can be used to perform cleaning with a second fluid, such as subsequent cleaning after delivery of the first fluid has been paused. This can limit contamination of the fluid lines, and can improve throughput in some embodiments of the present technology. Two fluid reservoirs can be used and coupled to separate sets of nozzles via the crosspiece to accommodate such configurations.

[0055] Figure 8 A schematic diagram is shown of exemplary nozzle orientations according to some embodiments of the present technology, and can illustrate a configuration incorporating a first plurality of fluid nozzles 805 and a second plurality of fluid nozzles 810, both shown as a direction in which fluid delivery can occur, such as along a second angle, and this can be in addition to a first angle as previously described. Figure 8Embodiments can be illustrated in which multiple rails can be used, and the multiple rails can each include multiple fluid nozzles as previously described. As shown, a first rail can be oriented in a first direction, and can include a first plurality of fluid nozzles 805 arranged in line along the rail in the first direction, and the first plurality of fluid nozzles 805 can be inverted about a rail center. Additionally, a second rail can be oriented in a second direction perpendicular to the first direction, and can include a second plurality of fluid nozzles 810 arranged in line along the rail in the second direction, and the second plurality of fluid nozzles 810 can also be inverted about a rail center. Although the first plurality of fluid nozzles and the second plurality of fluid nozzles can deliver the same fluid (including simultaneously), in some embodiments the first plurality of fluid nozzles can be used to perform cleaning with a first fluid, and the second plurality of fluid nozzles can be used to perform cleaning with a second fluid different from the first fluid.

[0056] Figure 9 A schematic diagram showing exemplary nozzle orientations according to some embodiments of the present technology is shown, and a configuration incorporating a combination of nozzle configurations can be illustrated, such as including nozzles as shown in Figure 7 Figure 8 Figure 8 For example, a first plurality of fluid nozzles can include nozzles 905 and 910, both of which are shown as directions in which fluid delivery can occur, such as along a second angle, and this can be in addition to a first angle as previously described. The configuration also includes a second plurality of fluid nozzles, which can include nozzles 905 and 910, both of which are shown as directions in which fluid delivery can occur, such as along a second angle, and this can be in addition to a first angle as previously described.

[0057] Additionally, embodiments can be illustrated in which multiple rails can be used, and the multiple rails can each include multiple fluid nozzles as previously described. As shown, a first rail can be oriented in a first direction, and can include a first plurality of fluid nozzles (including nozzles 905 and 910) arranged in line along the rail in the first direction, and the first plurality of fluid nozzles can be inverted about a rail center. Additionally, a second rail can be oriented in a second direction perpendicular to the first direction, and can include a second plurality of fluid nozzles (including nozzles 915 and 920) arranged in line along the rail in the second direction, and the second plurality of fluid nozzles can also be inverted about a rail center. While the first plurality of fluid nozzles and the second plurality of fluid nozzles can deliver the same fluid (including simultaneously), in some embodiments, nozzle 905 from the first plurality of fluid nozzles and nozzle 915 from the second plurality of fluid nozzles can be used to perform cleaning with a first fluid, and nozzle 910 from the first plurality of fluid nozzles and nozzle 920 from the second plurality of fluid nozzles can be used to perform cleaning with a second fluid different from the first fluid. By utilizing cleaning systems and methods of performance according to embodiments of the present technology incorporating tilted nozzles, improved cleaning can be performed on a range of substrates to reduce particle incorporation and contamination as compared to conventional techniques.

[0058] In the preceding description, for purposes of explanation, numerous details are set forth in order to provide an understanding of various embodiments of the present technology. However, it will be apparent to one skilled in the art that certain embodiments can be practiced without some or all of these details.

[0059] Having disclosed several embodiments, those skilled in the art will appreciate that various modifications, alternative constructions, and equivalents can be used without departing from the spirit of the embodiments. Additionally, a number of well-known processes and elements have not been described in order to avoid unnecessarily obscuring the present technology. Accordingly, the above description should not be taken as limiting the scope of the present technology.

[0060] Where a range of values is provided, it is understood that each intervening value, to the minimum resolvable between the upper and lower limits of that range, is also specifically disclosed. Any narrower range between any stated value or intervening value is encompassed within the scope of the present technology unless otherwise indicated. All ranges and sub-ranges are inclusive of the values that are the endpoints of the range or sub-range. Any reference to a number of steps or elements is not intended to limit the number of steps or elements to that number, unless the context clearly indicates otherwise. Any reference to a number of steps or elements is intended to encompass a number of steps or elements that is at least one, two, three, or four, unless the context clearly indicates otherwise.

[0061] As used herein and in the appended claims, the singular forms“a,”“an,” and“the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to“a nozzle” includes a plurality of such nozzles, and reference to“the aperture” includes reference to one or more apertures and equivalents thereof known to those skilled in the art, and so forth.

[0062] Also, as used in the specification and the appended claims, the words“comprise(s)”,“comprising”,“contain(s)”,“containing”,“include(s)”, and“including” are intended to specify the presence of stated features, integers, components, or operations, but they do not preclude the presence or addition of one or more other features, integers, components, operations, actions, or groups.

Claims

1. A cleaning chamber, comprising: a substrate support comprising a substrate set-down position; and a plurality of fluid nozzles facing the substrate support, wherein each fluid nozzle of the plurality of fluid nozzles is aligned and tilted relative to the substrate set-down position of the substrate support, each fluid nozzle delivering fluid in a non-overlapping respective spray pattern characterized by a leading edge and a trailing edge, wherein each leading edge of each non-overlapping respective spray pattern contacts the substrate at an interior angle greater than or about 90°.

2. The cleaning chamber of claim 1, wherein each fluid nozzle is operable to deliver fluid at greater than or about 500 psi.

3. The cleaning chamber of claim 1, wherein the plurality of fluid nozzles is a first plurality of fluid nozzles, and wherein the cleaning chamber comprises a second plurality of fluid nozzles.

4. The cleaning chamber of claim 3, wherein the first plurality of fluid nozzles is directed in a first direction toward the substrate set-down position, and wherein the second plurality of fluid nozzles is directed in a second direction opposite the first direction toward the substrate set-down position.

5. The cleaning chamber of claim 3, wherein each fluid nozzle of the first plurality of fluid nozzles is separated from each adjacent fluid nozzle of the first plurality of fluid nozzles by a gap, and wherein each fluid nozzle of the second plurality of fluid nozzles is positioned in alignment with the gap between two fluid nozzles of the first plurality of fluid nozzles.

6. The cleaning chamber of claim 3, wherein each fluid nozzle of the first plurality of fluid nozzles is disposed along a straight line in a first direction across the cleaning chamber, and wherein each fluid nozzle of the second plurality of fluid nozzles is disposed along a straight line in a second direction across the cleaning chamber perpendicular to the first direction.

7. The cleaning chamber of claim 3, further comprising: a first cleaning fluid reservoir fluidly coupled with the first plurality of fluid nozzles within the cleaning chamber; and a second cleaning fluid reservoir fluidly coupled with the second plurality of fluid nozzles within the cleaning chamber.

8. The cleaning chamber of claim 7, wherein the first cleaning fluid reservoir comprises a first cleaning fluid, and wherein the second cleaning fluid reservoir comprises a second cleaning fluid different from the first cleaning fluid.

9. The cleaning chamber of claim 1, wherein each fluid nozzle of the plurality of fluid nozzles defines a fluid port; and wherein each fluid port is characterized by a slit opening.

10. A method of substrate cleaning, comprising the steps of: positioning a substrate in a substrate cleaning chamber; and spraying cleaning fluid at the substrate from a plurality of fluid nozzles within the substrate cleaning chamber according to non-overlapping spray patterns, wherein each fluid nozzle of the plurality of fluid nozzles is tilted relative to the substrate such that a leading edge of the non-overlapping spray patterns contacts the substrate at an interior angle greater than or about 90°. ​ ​ ​ 11. The method of substrate cleaning of claim 10, further comprising the steps of: rotating the substrate within the substrate cleaning chamber while spraying the cleaning fluid.

12. The method of substrate cleaning of claim 11, wherein the cleaning fluid is sprayed at a fluid pressure of less than or about 250 psi.

13. The method of substrate cleaning of claim 11, further comprising the steps of: reversing a direction of rotation, and continuing to spray the cleaning fluid at the substrate.

14. The method of substrate cleaning of claim 10, wherein the cleaning fluid is sprayed at a fluid pressure of greater than or about 500 psi.

15. The method of substrate cleaning of claim 10, wherein the cleaning fluid comprises deionized water, hydrofluoric acid, or ammonium hydroxide.

16. The method of substrate cleaning of claim 10, wherein the cleaning fluid comprises a first cleaning fluid, the method further comprising the steps of: pausing the spraying of the first cleaning fluid; and spraying a second cleaning fluid at the substrate.

17. The method of substrate cleaning of claim 16, wherein the plurality of fluid nozzles is a first plurality of fluid nozzles, and wherein the second cleaning fluid is sprayed from a second plurality of fluid nozzles.

18. The method of substrate cleaning of claim 17, wherein each fluid nozzle of the first plurality of fluid nozzles is disposed along a line in a first direction across the substrate cleaning chamber, and wherein each fluid nozzle of the second plurality of fluid nozzles is disposed along a line in a second direction across the substrate cleaning chamber that is perpendicular to the first direction.

19. A cleaning chamber, comprising: a substrate support comprising a substrate set-down position; and a plurality of fluid nozzles facing the substrate support, wherein each fluid nozzle of the plurality of fluid nozzles is aligned and defines a fluid port characterized by non-overlapping spray patterns having leading and trailing edges, and wherein each fluid nozzle of the plurality of fluid nozzles is tilted relative to the substrate set-down position of the substrate support such that the leading edge of each non-overlapping spray pattern of the fluid port of each fluid nozzle of the plurality of fluid nozzles intersects the substrate at an interior angle greater than or about 90°.

20. The cleaning chamber of claim 19, wherein the substrate support comprises a rotatable drum, and wherein the plurality of fluid nozzles are coupled outside the rotatable drum along a sidewall of the cleaning chamber, and wherein each fluid nozzle is operable to deliver fluid at greater than or about 500 psi.

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