Method and system for monitoring, controlling and synchronizing a dispensing system

Abstract

Described herein are embodiments for monitoring and synchronizing a dispense system for a processing system. In one embodiment, pressure and flow sensors are used to determine the delay between a flow change event and an increase in flow rate, and this delay is used to detect defects or conditions within the dispense system. In one embodiment, the operation of the dispense system is synchronized using flow sensors. In one embodiment, simulation models or complex dispense profiles based on combined pressure / flow / spin / concentration sensor data are used to enable complex process recipes. In one embodiment, pressure and / or flow measurements between dispenses are used to detect dispense parameters and defects. In one embodiment, a camera and image processing are used to detect the flow rate from the dispense nozzle, and measurements between dispenses are used to detect dispense parameters and defects. One or more of the disclosed embodiments may be used in a processing system for microelectronic workpieces.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application No. 62 / 930,090, entitled “METHODS AND SYSTEMS TO MONITOR, CONTROL, AND SYNCHRONIZE DISPENSE SYSTEMS,” filed November 4, 2019, the disclosure of which is expressly incorporated by reference in its entirety herein.

[0002] The present disclosure relates to methods for the manufacture of microelectronic workpieces that include forming pattern structures on the microelectronic workpieces. [Background technology]

[0003] The formation of devices in a microelectronic workpiece typically involves a series of manufacturing techniques involving the formation, patterning, and removal of many layers of material on a substrate. To meet the physical and electrical specifications of current and next generation semiconductor devices, process flows are required to reduce feature dimensions while maintaining structural integrity for the various patterning processes.

[0004] As film thickness and critical dimension (CD) budgets continue to shrink, tighter uniformity control is required for coating fluids dispensed from dispensing systems for processing systems used in the manufacture of microelectronic workpieces. For example, in spin-coating processes, the coating fluid often passes through a filter and a pump, then through a nozzle, and onto a microelectronic workpiece, such as a semiconductor wafer, which is typically spinning on a rotating substrate holder. The dispensing system also includes valves, reservoirs, supply tanks, and / or other components. The cleanliness of the fluid and the flow rate at which the fluid is dispensed onto the wafer at a given time are important to minimize defects and provide good CD control. For example, gas or particles introduced into the filter will reduce the channels available for the fluid to pass through the filter membrane and increase or cause fluctuations in the pressure drop across the filter.

[0005] In a dispensing system without bubbles, the liquid is relatively incompressible and a pressure change will cause a nearly instantaneous change in flow rate. The flow rate at a given pressure is also related to the viscosity, which is an indicator of the polymer content in the liquid or conversely the solvent concentration in the liquid. In contrast, air bubbles present in any of the dispensing systems will compress under an increase in pressure. As such, the presence of air bubbles in the liquid will cause a delay between the applied pressure and the flow rate change. These flow rate delays reduce the stability of the dispensing rate. Air bubbles also impede filter performance by blocking membrane channels, can be nucleation sites for smaller particles to aggregate into larger particles, and can cause the polymer components of the liquid to fall out of solution.

[0006] The coating thickness of the dispensed liquid on the substrate is also an important parameter to control. The final coating thickness of the dispensed liquid over a spinning substrate for a microelectronic workpiece is a complex function of many variables including the rotation profile over time, the flow rate profile over time, and the solvent concentration over time. As the dispense volume decreases with more advanced process flows, the allowable combinations of these variables to provide a uniform thickness also decrease. Furthermore, the importance of synchronization between the dispense system and the rotation of the substrate increases.

[0007] FIG. 1A (PRIOR ART) is a diagram of an exemplary embodiment of a processing system 100 including a dispensing system 102 in which conditions such as air bubbles may occur and cause defects. Dispensing system 102 includes a filter 104, a pump 106 with a pressure sensor 116, a valve 112, a flow sensor 118, and a nozzle 114. A supply tank 120 supplies liquid 122 to dispensing system 102. Within dispensing system 102, liquid 122 passes through filter 104, pump 106, valve 112, flow sensor 118, and nozzle 114. Liquid 122 is then dispensed from nozzle 114 onto a substrate 109 for a microelectronic workpiece. Substrate 109 is held on a substrate holder 108, such as a vacuum chuck. Substrate holder 108 is rotated at a controlled speed by a spin motor 110 to facilitate dispensing of liquid 122 onto the surface of substrate 109. The liquid 122 may be a photoresist (PR) or other desired liquid.

[0008] During operation, dispensing system 102 uses filter 104, pump 106, valve 112, and nozzle 114 to dispense liquid 112 onto a rotating substrate 109. Available sensing devices include pressure sensor 116 and flow sensor 118, as well as an encoder (not shown) that tracks the rotation of spin motor 110. For a typical dispense of liquid 122, pressure is brought to a selected set point using pump 106 before valve 112 is opened. This controlled pressure helps to maintain a consistent dispense of liquid 122 through nozzle 114. The quality and quantity of the dispense are controlled by adjustments to the pressure set point and the rate at which valve 112 opens and closes.

[0009] To control the dispense volume, a process engineer of dispense system 102 adjusts the pressure of pump 106 by monitoring pressure sensor 116. In addition, the process engineer adjusts valve 112 to produce a visually acceptable dispense, such as a dispense without drips and erratic starts. A flow sensor 118 is often included between valve 112 and nozzle 114, although flow sensor 118 is often not used for dispense control.

[0010] Figure IB (Prior Art) is an exemplary embodiment of a diagram 150 for dispensing using dispensing system 102 shown in Figure IA (Prior Art). As shown, liquid pressure 152 is controlled to be constant at a selected set point. Spin rotation speed 156 of spin motor 110 is set to a selected level prior to dispensing of liquid. Valve 112 is then opened and flow rate 154 preferably remains at the same level for dispensing.

[0011] In addition to pressure control, video monitoring is also provided to allow process engineers to visually inspect the quality of the dispense. For example, the dispense system 102 can use cameras (e.g., running at 120 frames / sec) to enable monitoring of nozzle angle and position, nozzle contamination, dispense presence (on / off), dispense timing (start delay, end delay), presence of air bubbles, suckback position, and maintenance support for suckback setup and nozzle centering.

[0012] However, with previous dispensing techniques, air bubbles can form in the liquid and adversely affect defect performance and dispensing consistency. For example, air bubbles can form in filter 104 and become lodged in liquid 122 as it moves through dispensing system 102.

[0013] FIG. 1C (PRIOR ART) is an exemplary embodiment of a diagram 170 illustrating the flow rate at nozzle 114 in a first case 172 where no air bubbles are formed or present and a second case 174 where air bubbles are formed or present for liquid 122 flowing through nozzle 114. In the first case 172, no air bubbles are formed or present in liquid 122 in filter 104 or in tubing for dispensing system 102. As such, a high flow rate and fully laminar flow profile is achieved for liquid 122 flowing through nozzle 114 within 0.1 seconds after pressure is applied to dispensing system 102. For example, in the center of liquid 122 flowing through nozzle 114, a high flow rate of 0.08 meters per second (m / s) can be achieved. In contrast to the second case 174, air bubbles are formed or present in liquid in filter 104 or in tubing for dispensing system 102, resulting in a decrease in the flow rate of liquid 122 flowing through nozzle 114 after pressure is applied to dispensing system 102. For example, 0.1 seconds after pressure is applied, the flow rate in this second case is delayed and significantly reduced compared to the first case 172 due to the presence of air bubbles in the liquid 122. In one example, the flow rate of the liquid 122 flowing through the nozzle 114 may be 0.03 m / sec compared to 0.08 m / sec in the first case 172. Summary of the Invention [Means for solving the problem]

[0014] Described herein are embodiments for monitoring and synchronizing a dispense system for a processing system. Different or additional features, variations and embodiments may be implemented and related systems and methods may be utilized as well.

[0015] In one embodiment, pressure and flow sensors are used to determine the delay between a flow change event, such as the application of pressure or the opening of a valve, and an increase in flow rate, and this delay is used to detect and quantify gas within the dispensing system, match the performance of different modules, and / or detect other defects or conditions within the dispensing system.

[0016] In one aspect, a system for dispensing liquid for a microelectronic workpiece processing system is disclosed, the system including a pump coupled to receive the liquid to be dispensed, a nozzle coupled to receive the liquid from the pump and dispense the liquid onto the microelectronic workpiece, a pressure sensor coupled to sense a pressure in the liquid, a flow sensor coupled to sense a flow rate of the liquid, and a controller coupled to receive pressure information from the pressure sensor and flow information from the flow sensor and configured to determine one or more conditions within the system based on a delay between a flow change event and an increase in the flow rate.

[0017] In an additional embodiment, the pressure sensor is coupled between the pump and the nozzle, and the flow sensor is coupled between the pump and the nozzle. In a further embodiment, the flow change event includes a change in pressure. In a further embodiment, the system includes a valve, and the flow change event includes opening of the valve. In yet a further embodiment, the valve is coupled between the pump and the nozzle. In a further embodiment, the one or more conditions include at least one of air bubbles in the system, a condition of a filter in the system, or a change in viscosity of the liquid. In a further embodiment, the one or more conditions include a condition associated with recharging the pump.

[0018] In another aspect, a method of dispensing liquid for a microelectronic workpiece processing system is disclosed, the method including receiving a liquid to be dispensed with the dispensing system, causing a flow change event of the liquid in the dispensing system, sensing a flow rate of the liquid after causing the flow change event, and determining one or more conditions in the dispensing system based on a delay between the flow change event and the change in flow rate.

[0019] In an additional embodiment, the flow change event includes applying pressure to the liquid in the dispensing system, and determining includes determining one or more conditions in the dispensing system based on a delay between the application of pressure and an increase in flow rate. In a further embodiment, the flow change event includes opening a valve to allow flow of the liquid in the dispensing system, and determining includes determining one or more conditions in the dispensing system based on a delay between the opening of the valve and a change in flow rate. In a further embodiment, the one or more conditions include at least one of an air bubble in the dispensing system, a condition of a filter in the dispensing system, or a change in viscosity of the liquid.

[0020] In one embodiment, the operation of the dispense system is synchronized using a flow sensor, for example, the spin speed of the substrate can be synchronized with the flow rate.

[0021] In one aspect, a system for dispensing a liquid for a microelectronic workpiece processing system is disclosed, the system including a nozzle coupled to receive the liquid and dispense the liquid onto a microelectronic workpiece, a flow sensor coupled to sense a flow rate of the liquid, a substrate holder for the microelectronic workpiece, a spin motor coupled to rotate the substrate holder at a spin speed, and a controller coupled to receive flow rate information from the flow sensor and spin speed information from the spin motor and configured to synchronize the flow rate and the spin speed.

[0022] In an additional embodiment, the controller is configured to achieve a target uniformity in thickness of liquid applied to the microelectronic workpiece. In a further embodiment, the controller is configured to obtain the flow rate information and the spin speed information at a sample rate of at least one sample every 50 milliseconds or less. In a further embodiment, the controller is further configured to perform at least one of a feedback adjustment by adjusting a spin speed used to process a subsequent microelectronic workpiece or a feedforward adjustment by adjusting a spin speed used to process the same microelectronic workpiece in a subsequent processing step.

[0023] In another aspect, a method of dispensing a liquid for a microelectronic workpiece processing system is disclosed, the method including receiving a liquid to be dispensed with a dispensing system, dispensing the liquid onto the microelectronic workpiece, rotating the microelectronic workpiece at a spin speed during dispensing, sensing a flow rate of the liquid during dispensing, and synchronizing the flow rate and the spin speed.

[0024] In an additional embodiment, the synchronizing achieves a target uniformity in thickness for dispensing liquid onto a microelectronic workpiece.

[0025] In one embodiment, simulation models or complex dispense profiles based on combined pressure / flow / spin / concentration sensor data are used to enable more complex process recipes, identify bottle changes, enable tighter control of thickness specifications and / or other purposes. Filter life, chemical viscosity changes and / or other operating parameters may also be monitored with the described techniques.

[0026] In one aspect, a system for dispensing a liquid for a microelectronic workpiece processing system is disclosed, the system including a pump coupled to receive the liquid to be dispensed, a nozzle coupled to receive the liquid from the pump and to dispense the liquid onto the microelectronic workpiece, a pressure sensor coupled to sense a pressure in the liquid, a flow sensor coupled to sense a flow rate of the liquid, a substrate holder for the microelectronic workpiece, a spin motor coupled to rotate the substrate holder at a spin speed, and a controller, the controller coupled to receive pressure information from the pressure sensor, flow rate information from the flow sensor, and spin speed information from the spin motor, and the controller further configured to adjust at least one of the pressure, flow rate, or spin speed to achieve target parameters.

[0027] In an additional embodiment, the pressure sensor is coupled between the pump and the nozzle, and the flow sensor is coupled between the pump and the nozzle. In a further embodiment, the controller is further configured to adjust the pressure, the flow rate, or the spin speed by applying one or more process models. In a further embodiment, the pump includes a hydraulic pump having a piston controlled by the controller, and a displacement reading from the hydraulic pump is used as the pressure sensor. In a further embodiment, the system includes a mixer coupled between the pump and the nozzle and configured to mix the liquid with one or more solvents, and the controller is configured to adjust the solvent mixing by the mixer based on the one or more process models. In yet another embodiment, the controller is configured to adjust at least one of the flow rate, spin speed, or solvent mixing based on a detected change in at least one other of the flow rate, spin speed, or solvent mixing.

[0028] In another aspect, a method of dispensing a liquid for a microelectronic workpiece processing system is disclosed, the method including receiving a liquid to be dispensed with a dispensing system, applying a pressure to the liquid in the dispensing system, dispensing the liquid onto the microelectronic workpiece, rotating the microelectronic workpiece at a spin speed during dispensing, sensing a flow rate of the liquid during dispensing, and adjusting at least one of the pressure, flow rate, or spin speed to achieve target parameters.

[0029] In additional embodiments, the method includes applying one or more process models to adjust the pressure, flow rate, or spin speed. In further embodiments, the method includes mixing the liquid with one or more solvents prior to dispensing to create a solvent concentration in the liquid, detecting a change in at least one of the flow rate, spin speed, or solvent concentration, and adjusting at least one of the flow rate, spin speed, or solvent mixing based on the detection.

[0030] In one embodiment, pressure and / or flow measurements during dispensing are used to detect dispensing parameters such as air bubbles, viscosity changes, particles and / or other parameters.

[0031] In one aspect, a system for dispensing liquid for a microelectronic workpiece processing system is disclosed, the system including a filter coupled to receive the liquid to be dispensed, a pump coupled to receive the liquid from the filter, a nozzle coupled to receive the liquid from the pump and to dispense the liquid onto the microelectronic workpiece, a pressure sensor coupled to sense a pressure of the liquid in the system, a flow sensor coupled to sense a flow rate of the liquid in the system, and a controller, the controller coupled to receive pressure information from the pressure sensor and flow rate information from the flow sensor, and the controller configured to determine one or more conditions in the system based on a comparison of the pressure or flow rate or the pressure and flow rate over multiple dispenses.

[0032] In an additional embodiment, the one or more conditions include at least one of an air bubble introduced into the system, a change in viscosity of the liquid, or a condition of a filter. In a further embodiment, the pressure sensor is associated with the pump or associated with the filter.

[0033] In another aspect, a method of dispensing liquid for a microelectronic workpiece processing system is disclosed, the method including receiving a liquid to be dispensed with the dispensing system, dispensing the liquid onto a microelectronic workpiece, sensing a pressure of the liquid during dispensing, sensing a flow rate of the liquid during dispensing, repeating the receiving, dispensing and sensing over multiple dispenses of the liquid, and determining one or more conditions within the system based on a comparison of the pressure or flow rate or the pressure and flow rate over the multiple dispenses.

[0034] In additional embodiments, the one or more conditions include at least one of air bubbles introduced into the system, a change in viscosity of the liquid, or a condition of a filter.

[0035] In one embodiment, a camera and image processing are used to detect the flow rate from the dispensing nozzle and compare the flow rate detection between dispenses to detect dispense parameters such as air bubbles, viscosity changes, particles and / or other parameters.

[0036] In one aspect, a system for dispensing liquid for a microelectronic workpiece processing system is disclosed, the system including a pump coupled to receive the liquid to be dispensed, a nozzle coupled to receive the liquid from the pump and dispense the liquid onto the microelectronic workpiece, a camera coupled to capture images of the liquid dispensed through the nozzle, the camera configured to capture image data at 500 frames / second or greater, and a controller coupled to receive the image data and determine a flow rate of the liquid based on the image data. The controller is also configured to determine one or more conditions within the system based on a comparison of the flow rates over multiple dispenses.

[0037] In an additional embodiment, the one or more conditions include at least one of an air bubble introduced into the system, a change in viscosity of the liquid, or a condition of a filter. In a further embodiment, the camera is configured to capture image data at 2000 frames / second or greater.

[0038] In another aspect, a method of dispensing liquid for a microelectronic workpiece processing system is disclosed, the method including receiving a liquid to be dispensed with the dispensing system, dispensing the liquid onto a microelectronic workpiece through a nozzle, capturing images of the dispensing of the liquid through the nozzle at 500 frames per second or more, generating a flow rate of the liquid during dispensing based on the capturing, repeating the receiving, dispensing, capturing and generating for multiple dispensings of the liquid, and determining one or more conditions within the system based on a comparison of the flow rates across the multiple dispensings.

[0039] In an additional embodiment, the one or more conditions include at least one of an air bubble introduced into the system, a change in viscosity of the liquid, or a filter condition. In a further embodiment, the capture occurs at 2000 frames / second or greater.

[0040] Different or additional features, variations and embodiments may also be implemented and the associated systems and methods may be utilized as well.

[0041] A more detailed understanding of the present invention and its advantages can be obtained by reference to the following description in conjunction with the accompanying drawings, in which like reference numerals indicate like features, and in which it should be noted, however, that the accompanying drawings depict only exemplary embodiments of the disclosed concepts and therefore should not be considered as limiting the scope, as the disclosed concepts may be applied to other equally effective embodiments. [Brief description of the drawings]

[0042] [Figure 1A]PRIOR ART An exemplary embodiment of a processing system is provided that includes a dispensing system in which conditions such as air bubbles can occur and cause defects. [Figure 1B] PRIOR ART An exemplary embodiment of a processing system is provided that includes a dispensing system in which conditions such as air bubbles can occur and cause defects. [Figure 1C] PRIOR ART An exemplary embodiment of a processing system is provided that includes a dispensing system in which conditions such as air bubbles can occur and cause defects. [Figure 2A] A first exemplary embodiment is provided in which pressure and flow sensors are used to determine the delay between a flow change event, such as the application of pressure or the opening of a valve, and an increase in flow rate, which delay is used to detect defects, conditions, or other operational details of the dispensing system. [Figure 2B] A first exemplary embodiment is provided in which pressure and flow sensors are used to determine the delay between a flow change event, such as the application of pressure or the opening of a valve, and an increase in flow rate, which delay is used to detect defects, conditions, or other operational details of the dispensing system. [Figure 2C] A first exemplary embodiment is provided in which pressure and flow sensors are used to determine the delay between a flow change event, such as the application of pressure or the opening of a valve, and an increase in flow rate, which delay is used to detect defects, conditions, or other operational details of the dispensing system. [Figure 3A] A second exemplary embodiment is provided in which the operation of a dispensing system is synchronized using a flow sensor. [Figure 3B] A second exemplary embodiment is provided in which the operation of a dispensing system is synchronized using a flow sensor. [Figure 4A] A third exemplary embodiment is provided that enables advanced and complex process recipes using complex dispense profiles or simulation models based on combined pressure / flow / spin / concentration sensor data. [Figure 4B]A third exemplary embodiment is provided that enables advanced and complex process recipes using complex dispense profiles or simulation models based on combined pressure / flow / spin / concentration sensor data. [Diagram 5] A fourth exemplary embodiment is provided in which pressure and / or flow measurements during dispense are used to detect dispense parameters and defects. [Figure 6] A fifth exemplary embodiment is provided in which a camera and image processing are used to detect flow rate from a dispense nozzle, and measurements between dispenses are used to detect dispense parameters and defects. [Figure 7] Exemplary embodiments of a processing system for microelectronic workpieces that can utilize one or more of the embodiments and techniques described herein are provided. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0043] Described herein are embodiments for monitoring and synchronizing dispense systems for a processing system. Various advantages and implementations can be realized while utilizing the processing techniques described herein.

[0044] 2A-2C provide a first exemplary embodiment in which pressure and flow sensors are used to determine a delay between application of pressure and an increase in flow rate, which is used to detect defects or conditions in the dispensing system. FIGS. 3A-3B provide a second exemplary embodiment in which the operation of the dispensing system is synchronized using flow sensors. FIGS. 4A-4B provide a third exemplary embodiment in which simulation models or complex dispense profiles based on combined pressure / flow / spin / concentration sensor data are used to enable advanced and complex processing recipes. FIG. 5 provides a fourth exemplary embodiment in which pressure and / or flow measurements between dispenses are used to detect dispense parameters and defects. FIG. 6 provides a fifth exemplary embodiment in which a camera and image processing are used to detect the flow rate from the dispense nozzle, and measurements between dispenses are used to detect dispense parameters and defects. FIG. 7 provides an exemplary embodiment of a processing system for microelectronic workpieces that can utilize one or more of these embodiments and techniques described herein.

[0045] In certain aspects, the disclosed embodiments use flow sensors and / or pressure or displacement sensors to monitor, control and / or synchronize the dispense system. For example, the disclosed embodiments are used to (1) improve the time required for start-up or filter replacement by identifying when remaining gas is pushed out of the filter or dissolved, (2) determine if small air bubbles have been introduced into the system that may adversely affect defect density and film thickness uniformity, (3) determine when a bottle change changes the solids content of the liquid and corrections to the process recipe need to be made, (4) create a profile of flow rate over time that can be analyzed to match different coat modules, synchronize the flow to the spin motor, make feed-forward corrections to the spin motor determined by a model of the coat process, and / or (5) achieve other improvements to the operation of the dispense system. For certain embodiments, measurements of flow delay and / or flow rate via time profiles are used to enable complex, controlled combinations of dispense speeds and rotation / spin speeds that are not possible with current solutions due to repeatability concerns. The disclosed embodiments may also be used to enable further reductions in minimum dispense volumes, and the increased reproducibility achieved by the disclosed embodiments may enable dispense volumes to be used below current dispense volume levels used in processing systems.

[0046] Example 1 - Flow / Pressure Profile For incompressible fluids, when pressure is applied or other flow change events occur, such as the opening of a valve, the flow rate will change almost instantaneously. Therefore, a delay can be considered an indication of air bubbles in the dispensing system. These air bubbles tend to cause defects and lead to less consistent dispensing, especially if filters are included in the system. By examining the delay between the flow change event (e.g., the application of pressure or the opening of a valve) and the change in flow rate, the presence and amount of air bubbles can be monitored as well as tool performance.

[0047] As described below, the difference between flow rate and pressure can be used to indicate a metric of the presence of gas in the dispensing system. Additionally, the difference between flow rate and applied pressure can also be used to determine when a filter has been properly purged or needs to be replaced. Still further, the difference between flow rate and applied pressure can be used to determine when a change in viscosity of the liquid has occurred, such as when a change in supply bottle causes a viscosity change. In one embodiment, a flow sensor included between the supply tank and the pump can also be used to monitor the difference between flow rate and pressure over time while the pump is being recharged.

[0048] As also described below, delays between other flow change events and flow rate changes can also be used to determine air bubbles in the dispensing system and / or for other purposes. For example, where a dispensing system maintains a controlled pressure before opening a valve to cause a dispense, the delay between the valve opening and the flow signal from a flow sensor can be used to determine the presence of an air bubble in the dispensing system. Additionally, a current flow profile can be compared to a desired flow profile after a flow change event, such as application of pressure or opening of a valve, to determine the presence of an air bubble. Additionally, such delays or flow profiles can be detected and used to maintain consistency between multiple different dispense operations between different runs of a particular dispense system or between runs of different dispense systems. Other advantages can also be achieved while still utilizing the techniques described herein.

[0049] 2A is a block diagram of an exemplary embodiment of a processing system 200 including a dispense system 102 having a pump 106 with a pressure sensor 116, a flow sensor 204 disposed between a supply tank 120, and a flow sensor 118 disposed between the pump 106 and a nozzle 114. Note that the flow sensor 118 may be disposed in other locations, such as between the supply tank 120 and the pump 106. A controller 202 receives this pressure and sensor information from the pressure sensor 116 and the flow sensor 118 / 204 and controls the dispense system 102. The dispense system 102 also includes a filter 104 and a valve 112. The filter 104 is disposed between the flow sensor 204 and the pump 106, although the filter 104 may be disposed in other locations. The supply tank 120 supplies the dispense system 102 with a liquid 122. Within dispensing system 102, liquid 122 passes through flow sensor 204, filter 104, pump 106, valve 112, flow sensor 118, and nozzle 114. Liquid 122 is then dispensed from nozzle 114 onto a substrate 109 for a microelectronic workpiece. Substrate 109 is held on a substrate holder 108, such as a vacuum chuck. Substrate holder 108 is rotated at a controlled speed by a spin motor 110 to facilitate dispensing of liquid 122 on the surface of substrate 109. Liquid 122 may be photoresist (PR) or other desired liquid.

[0050] 2B is an exemplary embodiment of a diagram 250 for dispensing using the system of FIG. 2A when gas is present in dispensing system 102. As shown, a flow change event 252, such as the application of pressure by pump 106 or the opening of valve 112, occurs in dispensing system 102. However, the corresponding flow rate 254 shows a delayed ramp to a peak followed by a ramp down. The delay in the change in flow rate 254 compared to the flow change event 252 indicates the presence of gas in dispensing system 102. As such, this delay can be used to detect and quantify air bubbles in the system.

[0051] Figure 2C is an example embodiment of a diagram 270 for dispensing using the system of Figure 2A when no gas is present in dispensing system 102. As shown, a flow change event 252, such as the application of pressure by pump 106 or the opening of valve 112, occurs within dispensing system 102, as did in Figure 2A. However, the ramp of flow rate 274 in Figure 2C has little or no delay in response to this flow change event 252. This lack of delay in the change in flow rate 274 compared to flow change event 252 indicates that no air bubbles are present within dispensing system 102.

[0052] In one embodiment, the liquid to be dispensed is pre-pressurized with pump 106 before valve 112 opens, and flow change event 252 represents a valve opening signal sent from valve 112 to controller 202. The delay between this valve opening signal and a change in flow rate 254 can be used by controller 202 to determine the presence of air bubbles in the liquid to be dispensed. In contrast, the lack of delay between this valve opening signal and a change in flow rate 274 can be used by controller 202 to determine the absence of air bubbles in the liquid to be dispensed.

[0053] In one embodiment, a comparison of pressure / flow profiles is used to determine the presence and amount of gas in the system that may increase defects. In additional embodiments, the magnitude of flow at controlled pressures can be used to provide information about the viscosity of the fluid or the condition of the filter, and this information can be provided to a user of the dispensing system. Additionally, the control enabled by the disclosed embodiments can be used to achieve uniform and / or repeatable dispensing without the need for constant pressure during dispensing, as is required in many conventional solutions. Since constant pressure requires time for the dispensing system to equilibrate, removing this limitation allows for faster throughput or additional time for slower filtration, which typically improves filtration results.

[0054] In one embodiment, pressure and flow are monitored during a portion of a dispense cycle of dispensing system 102 as pump 106 is refilled, and this monitoring is used to determine the status of the pump, such as when a reload is successfully completed. Additionally, the flow rate at a given applied pressure provides information that may be relevant to operations such as (1) timing a bottle change, (2) determining if the viscosity has shifted, (3) timing a filter change, (4) understanding filter life, (5) understanding priming of the filter and whether enough gas is being removed to fully utilize the filter membrane, (6) module number to understand potential differences in fault performance, and / or (7) other status of dispensing system 102.

[0055] In one embodiment, information about the gas in the filter 104 is obtained by comparing the timing of the pressure versus flow signals during the reload of the pump 106. To provide these comparisons, a flow sensor 204 is included between the chemical source provided by the supply tank 120 and the pump 106. In a further embodiment, the pressure is ramped up during the pump reload step instead of leaving the pressure at a pre-adjusted level. The flow rates and pressures can then be compared.

[0056] In one embodiment, pressure / flow comparisons are used to determine the condition of the filter 104. These comparisons allow the performance of the filters to be compared and the life of the filter to be better understood (e.g., pressure should increase over time). As the filter ages, it will collect more particles that block available paths through the filter membrane, and this increase in particles increases the pressure drop across the filter 104 and increases the flow rate through the remaining channels of the filter 104. Both of these effects often correlate with an increase in defects. For example, any gas present in the liquid 122 can be a nucleation site for defects. Understanding the flow caused by downstream pressure will indicate when the filter performance is degrading and predictive maintenance is required. Additionally, the average flow rate at a given pressure can be tracked and compared per module, per hour since filter change, or per hour since bottle change.

[0057] In one embodiment, the change in flow rate with applied pressure is used to indicate a change in viscosity of the liquid 122. For example, if the viscosity changes, the drying rotation speed of the spin motor 110 may need to be adjusted.

[0058] Pressure / flow comparisons and profiles can also be used to detect other conditions in the dispensing system 102 .

[0059] Embodiment 2 - Flow / Spin Synchronization 2A, a flow sensor 118 can be included between the pump and the nozzle 114. This flow sensor 118 and a sensor (not shown) monitoring the spin speed of the spin motor 110 (e.g., at time increments of tens of milliseconds) can be used to create sensor profiles correlating flow rate to spin speed. These flow / spin sensor profiles can be used to adjust the rotational speed of the spin motor 110 relative to the flow rate in a process recipe to achieve consistent or identical thickness uniformity for the dispensed liquid 122.

[0060] 3A is a block diagram of an exemplary embodiment of a processing system 300 including a dispense system 102 having a controller 302 configured to synchronize the spin speed of a spin motor 110 to a flow rate detected using a flow sensor 118. By applying this synchronization, the controller 302 can, in part, achieve a target uniformity in the thickness of liquid 122 applied to a substrate 109 of a microelectronic workpiece. Dispense system 102 also includes a filter 104, a pump 106, a valve 112, and a nozzle 114. A supply tank 120 supplies liquid 122 to dispense system 102. Within dispense system 102, liquid 122 passes through filter 104, pump 106, valve 112, flow sensor 118, and nozzle 114. Liquid 122 is then dispensed from nozzle 114 to a substrate 109 for a microelectronic workpiece. Substrate 109 is held on a substrate holder 108, such as a vacuum chuck. The substrate holder 108 is rotated at a controlled speed by a spin motor 110 to facilitate dispensing of the liquid 122 on the surface of the substrate 109. The liquid 122 may be a photoresist (PR) or other desired liquid.

[0061] During operation, the flow rate detected by the flow sensor 118 located between the pump 106 and the nozzle 114 is combined by the controller 302 with detailed information about the spin speed from the spin motor 110. Although the flow sensor information and the spin speed information have been obtained previously, the embodiment of FIG. 3 samples this information at a high rate (e.g., at a sample rate of 50 milliseconds (ms) or less, preferably at least one sample every 10 ms or less) and then matches the profile of sampled values ​​from each sensor over time. If a shift in the delta of the two profiles occurs from wafer to wafer or module to module, this shift can result in reduced thickness uniformity. If a shift is observed by the controller 302 through the profile matching, the controller 302 can use a feedback or feedforward control loop to maintain thickness uniformity. For example, in a feedback loop, the timing of the spin motor 110 can be adjusted for the next wafer or microelectronic workpiece. As such, in a feedback implementation, the spin motor 110 is adjusted to match the flow. In a feed-forward loop, later steps in the spin recipe can be adjusted to improve thickness uniformity on the same wafer or microelectronic workpiece, so in a feed-forward implementation, the cast speed and / or reflow step for subsequent processing steps for the same wafer are adjusted to better match the target thickness on the same wafer.

[0062] FIG. 3B is an exemplary embodiment of a diagram 340 for dispensing using the system of FIG. 3A when a feedback and / or feedforward loop is applied to synchronize the flow rate and spin speed. For dispensing 350, the flow rate 352 of the liquid 122 and the spin speed 354 of the spin motor 110 are sampled and provided to the controller 302. For example, this sampling may occur at a sample rate of at least one sample every 50 milliseconds or less, preferably every 10 milliseconds or less. The controller 302 determines whether there is any change in the current flow rate / spin speed compared to a base profile or compared to a previous wafer or process run. In the case of a feedback implementation, this flow / spin speed comparison is used by the controller 302 to make one or more adjustments to the flow / spin parameters for the next wafer or microelectronic workpiece to be processed. For example, the controller 302 may make a start timing adjustment 356, an end timing adjustment 358, and / or another adjustment. In a feedforward implementation, this flow rate / spin speed comparison is used by controller 302 to make one or more adjustments to parameters of a subsequent processing step applied to the same wafer or microelectronic workpiece. For example, in a subsequent processing step 260, the spin speed of spin motor 110 may be adjusted by controller 302, such as an adjustment 364 to the start timing, an adjustment 362 to the magnitude of the spin speed, and / or another adjustment.

[0063] Embodiment 3 - Pressure / Flow / Spin / Concentration Profiles In addition to the embodiments of Figures 2A-2C and 3A-3B, pressure, flow, spin and / or concentration information can be used to control more complex dispense recipes with repeatability not possible with current solutions. For example, dispense recipes that are sensitive to pressure / flow / spin / concentration timing can be implemented and used with the disclosed technology.

[0064] 4A is a block diagram of an example embodiment of a processing system 400 including a dispensing system 102 having a hydraulic pump 404 and a controller 402 configured to apply feed-forward and / or feedback control. Dispensing system 102 also includes a filter 104, a flow sensor 118, and a nozzle 114. A supply tank 120 supplies a liquid 122 to dispensing system 102. Within dispensing system 102, liquid 122 passes through filter 104, pump 106, valve 112, flow sensor 118, and nozzle 114. In addition, dispensing system 102 may include a mixer 408 configured to provide solvent mixing of liquid 122 with one or more solvents prior to dispensing through nozzle 114. Liquid 122 is then dispensed from nozzle 114 onto a substrate 109 for a microelectronic workpiece. Substrate 109 is held on a substrate holder 108, such as a vacuum chuck. The substrate holder 108 is rotated at a controlled speed by a spin motor 110 to facilitate dispensing of the liquid 122 on the surface of the substrate 109. The liquid 122 may be a photoresist (PR) or other desired liquid.

[0065] The controller 402 controls the hydraulic pump 404, solvent mixing for the mixer 408, spin speed for the spin motor 110, and / or other components. The controller 402 also receives pressure data from a pressure sensor 116 associated with the hydraulic pump 404, flow rate data from a flow sensor 118, spin speed data from the spin motor 110, and / or other operational data. The controller 402 may also control the operation of the dispensing system 102 using one or more models 410. For example, coat simulation models can be used to determine ideal dispense profiles and / or recipe combinations of chemistry and surface contact angles, and these coat simulation models can be applied by the controller 402 to control the components of the dispensing system 102.

[0066] The hydraulic pump 404 facilitates precise control of pressure and provides variable dispense rates. A piston for the hydraulic pump 404 is adjusted by the controller 402 to control the displacement of hydraulic fluid. The pressure and flow rate of the liquid 122 is dependent on this displacement as controlled by the controller 402. The hydraulic pump 404 also allows the embodiment 400 to be implemented without valves.

[0067] Controller 402 can provide feed-forward and / or feedback control. For example, feed-forward adjustments can be made by controller 402 to adjust hydraulic pump 404 and / or spin motor 110 based on the delay in flow rate after application of pressure. Additionally, the improved repeatability and synchronization provided by controller 402 allows complex dispense profiles to be used. For example, controller 402 can receive pressure information from pressure sensor 116, flow rate information from flow sensor 118, and spin speed information from spin motor 110, and controller 402 can use this information to adjust pressure, flow rate, and spin speed to achieve target parameters. For example, these techniques can be used to perform identical dispenses from wafer to wafer. Additionally, dispenses can be optimized for minimum volume and / or pressure stability.

[0068] During operation, any desired combination of flow rate over time, rotation speed over time, and concentration over time can be applied using the controller 402. Additionally, if the system is monitored for, for example, air bubbles, differences between modules, and / or other pressure-based analytics, the use of a hydraulic pump 404 allows displacement readings from the pump 404 to replace the pressure sensor 116 of FIGS. 2A and 3A. For example, the piston displacement can be automatically adjusted to achieve a desired flow rate profile in real time. The flow rate profile can also be synchronized to the rotation speed of the spin motor 110 and / or the solvent / polymer mixture of the coating liquid 122 provided by the mixer 408. A simulation-based model of the coating process can be used as one of the models 410 to achieve and maintain a desired thickness uniformity of the film formed by the dispensed liquid 122. In certain embodiments, the simulation model can be a computational fluid dynamics simulation based on chemical properties, a simplified model based on regression of empirical data, and / or other models. Still further, if there is a change in one of the three flow / spin / concentration profiles, such as an unavoidable change, the other profiles can be adjusted to compensate. If other sensors inside or outside of dispensing system 102 indicate changes to the thickness uniformity, one or more of the three profiles can be adjusted to maintain uniformity.

[0069] 4B is an exemplary embodiment of a diagram 450 for dispensing using the system of FIG. 4A when a complex profile is applied by the controller 402. As shown, a complex flow rate 452 for the liquid 122 is applied along with a complex spin speed 456 for the spin motor 110. In addition, the concentration 454 for the solvent mix provided by the mixer 408 is also adjusted over time. Other dispense parameters may also be adjusted using the complex profile based on additional control provided by the controller 402 in embodiment 400.

[0070] Embodiment 4 - Monitoring between dispenses In certain respects, the disclosed embodiments provide dispense-to-dose improvements through additional sensor systems and / or sensor-based signal analysis methods. These disclosed embodiments provide additional monitoring and / or analysis methods that improve dispense parameters, provide dispense flow rate matching, and provide anomaly / excursion monitoring. The disclosed embodiments achieve tighter dispense-to-dose control and dispense repeatability compared to previous solutions. For example, the disclosed embodiments not only improve flow rate control within a dispense, but also improve flow rate control over time between dispenses. Additionally, the disclosed embodiments allow for more rapid detection of dispense system excursions that affect the dispense flow rate, reducing the number of wafers requiring rework. These excursions include air bubbles introduced into the filter or pump, changes in viscosity, monitoring of clogged or contaminated filters, and / or other system excursions.

[0071] 5 is a block diagram of an exemplary embodiment of a processing system 500 including a dispense system 102 having one or more pressure sensors 504 and having one or more flow sensors 118 to facilitate detection of system excursions. For example, a pressure monitoring system is achieved by adding a pressure sensor 504 across a filter 104 for dispense system 102, a pump 106 for dispense system 102, or both. Pressure sensor 504 may also be added at a different location or additional locations within dispense system 102. Flow monitoring is achieved by adding a flow sensor 118 between valve 112 and nozzle 114, where the flow sensor may be located at a different location or other locations. A controller 502 receives pressure information from pressure sensor 504 and flow information from flow sensor 118, and controller 502 controls dispense system 102. Dispense system 102 also includes a filter 104 and a pump 106 located between supply tank 120 and valve 112. A supply tank 120 supplies liquid 122 to dispensing system 102. Within dispensing system 102, liquid 122 passes through filter 104, pump 106, valve 112, flow sensor 118, and nozzle 114. Liquid 122 is then dispensed from nozzle 114 onto a substrate 109 for a microelectronic workpiece. Substrate 109 is held on a substrate holder 108, such as a vacuum chuck. Substrate holder 108 is rotated at a controlled speed by a spin motor 110 to facilitate dispensing of liquid 122 onto the surface of substrate 109. Liquid 122 may be photoresist (PR) or other desired liquid.

[0072] During operation, between dispenses of pressure and / or flow signals (e.g., D n ~D n-1) can be performed to identify air bubbles that may be present in the dispense system 102. These air bubbles can induce significant pressure and / or flow rate fluctuations that can instantly affect dispense rate control at the wafer. For example, due to differences in compressibility of liquid versus gas, air bubbles in the liquid 122 can cause significant fluctuations between a dispense when the air bubble is present compared to a dispense when the air bubble is not present. Additionally, a comparison of the current dispense with a previous dispense (e.g., D n ~D n-1 , D n ~D n-2 , D n ~D n-3 A comparison of the pressure and / or flow signals to a previous dispense (e.g., D ) that occurs over a longer time frame of the current dispense can be performed to identify viscosity changes of the material that have occurred in the dispensing system 102. These viscosity changes can induce significant pressure / flow signal shifts and trends over a relatively small number of iterations. Still further, a comparison of the pressure and / or flow signals to a previous dispense (e.g., D ) that occurs over a longer time frame of the current dispense can be performed to identify viscosity changes of the material that have occurred in the dispensing system 102. n ~D n-500 , D n ~D n-1000 , D n ~D n-1500 A comparison of the pressure and / or flow signals to a pressure signal, pressure drop, or pressure drop (e.g., pressure drop ...

[0073] Embodiment 5 - Image-based dispense-to-dispense monitoring Video monitoring of the dispense nozzle has been provided in previous solutions, which operates to monitor nozzle angle and position, nozzle contamination, presence of dispense (on / off), timing of dispense (time start delay, end delay), presence of air bubbles, location of suckback, and maintenance support of suckback setup and nozzle centering. However, these previous systems used cameras operating at 120 frames per second (fps) or less. As described below, the disclosed embodiments recognize that increasing the frame rate to 500 fps or more, preferably 2000 fps or more, allows for accurate determination of flow rate. For example, by applying image processing using edge detection algorithms, the front end position of liquid 122 can be detected over multiple frames as liquid 122 flows from nozzle 114 through the gap between nozzle 114 and substrate 109. The flow rate can then be determined, for example, at the start of flow through nozzle 114 and at the end of flow.

[0074] 6 is a block diagram of an exemplary embodiment of a processing system 600 including a dispensing system 102 having a camera 604 to facilitate detection of flow rate in addition to other parameters. A controller 602 receives this image data from the camera 604 and pressure information from a pressure sensor 116 and controls the dispensing system 102. The dispensing system 102 also includes a filter 104, a pump 106 with a pressure sensor 116, a valve 112, a flow sensor 118, and a nozzle 114. A supply tank 120 supplies a liquid 122 to the dispensing system 102. Within the dispensing system 102, the liquid 122 passes through the filter 104, the pump 106, the valve 112, the flow sensor 118, and the nozzle 114. The liquid 122 is then dispensed from the nozzle 114 onto a substrate 109 for a microelectronic workpiece. The substrate 109 is held on a substrate holder 108, such as a vacuum chuck. The substrate holder 108 is rotated at a controlled speed by a spin motor 110 to facilitate dispensing of the liquid 122 on the surface of the substrate 109. The liquid 122 may be a photoresist (PR) or other desired liquid.

[0075] During operation, the camera 604 captures images of the liquid 122 as it is dispensed from the nozzle 114, the images being captured at 500 fps or greater and preferably 2000 fps or greater. The controller then receives and processes the image data from the camera 604 to determine the flow rate of the liquid. For example, the flow rate at the start of dispense and at the end of dispense versus time, taking into account geometry, can be estimated using an edge detection algorithm per video frame analysis. This flow rate detection can be used in part to achieve good dispense start and end repeatability between modules. Additionally, the flow rate information extracted from the image data can be combined with pressure information and / or other information received by the controller 602 to facilitate the determination of operating conditions. Additionally, a comparison of the initial flow rate (and end of dispense flow rate) versus time between dispenses (e.g., D n ~D n-1 ) can be performed to identify air bubbles that may be present in the dispense system 102. These air bubbles can induce significant pressure fluctuations that can instantly affect dispense rate control at the wafer. For example, due to differences in compressibility of liquid versus gas, air bubbles in the liquid 122 can cause these significant fluctuations between a dispense when an air bubble is present compared to a dispense when no air bubble is present. Additionally, the current dispense can be compared to a previous dispense (e.g., D n ~D n-1 , D n ~D n-2 , D n ~D n-3 A comparison of flow rates against a previous dispense (e.g., D) that occurs over a longer time frame of the current dispense can be performed to identify viscosity changes of the material that have occurred in the dispense system 102. These viscosity changes can induce significant pressure signal shifts / trends over a relatively small number of iterations. n ~D n-500 , D n ~D n-1000 , D n ~D n-1500A comparison of the flow rate to the pressure in the filter 104 for the dispense system 102 can be performed to identify particle buildup in the filter 104 for the dispense system 102. Particle buildup will inevitably occur in the filter 104, and this particle buildup can induce significant pressure signal changes or trends that are detectable over a longer time frame of dispense repetitions. These changes or trends can be used to determine when the filter 104 needs to be cleaned or replaced.

[0076] EMBODIMENT 6 - PROCESSING SYSTEM ENVIRONMENT FIG. 7 is an exemplary embodiment of a processing system 700 of FIG. 7 for a microelectronic workpiece that may use one or more of the embodiments described herein. As described herein, the processing system 700 may include a pressure sensor, a flow sensor, and / or a flow detector in the dispensing system 102 to facilitate dispensing of materials in a processing chamber 710 for the processing system 700. A substrate 109 is disposed in the processing chamber 710. Further, the substrate 109 (a semiconductor wafer in one example) is held on a substrate holder 108, such as a vacuum chuck. A spin motor 110 may be configured to rotate the substrate holder 108 at a controlled speed to facilitate formation of a film layer on a surface of the substrate 109. The rotation and rotation speed may be controlled, for example, by a controller 702. A supply tank 120 supplies the dispense system 102 with a liquid 122, which is dispensed onto the substrate 109. The dispense system 102 and associated components may be implemented using one or more of the embodiments described herein.

[0077] The controller 702 is coupled to receive sensor, control and operational information from components of the processing system 700, and the controller operates to control the components and achieve the functions described herein. The controller 702 represents the controller 202 of FIG. 2A, the controller 302 of FIG. 3A, the controller 402 of FIG. 4A, the controller 502 of FIG. 5A, and / or the controller 602 of FIG. 6A. The controller 702 can be implemented in a variety of ways. For example, the controller 702 can be a computer. In another example, the controller 702 includes one or more programmable integrated circuits programmed to provide the functions described herein. For example, one or more processors (e.g., microprocessors, microcontrollers, central processing units, etc.), programmable logic devices (e.g., complex programmable logic devices (CPLDs), field programmable gate arrays (FPGAs), etc.), and / or other programmable integrated circuits can be programmed with software or other program instructions to implement the functions of the inhibited plasma processing recipe. It should be further noted that the software or other program instructions can be stored on one or more non-transitory computer readable media (e.g., memory storage elements, FLASH memory, DRAM memory, reprogrammable storage elements, hard drives, floppy disks, DVDs, CD-ROMs, etc.) and that the software or other program instructions, when executed by a programmable integrated circuit, cause the programmable integrated circuit to perform the processes, functions and / or capabilities described herein. Other variations can be implemented.

[0078] It should be noted that throughout this specification, reference to "one embodiment" or "an embodiment" means that a particular feature, structure, material, or characteristic described with respect to that embodiment is included in at least one embodiment of the invention, but may not be present in all embodiments. Thus, the phrases "in one embodiment" or "in an embodiment" appearing in various places throughout this specification do not necessarily refer to the same embodiment of the invention. Furthermore, particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments. In other embodiments, various additional layers and / or structures may be included and / or described features may be omitted.

[0079] As used herein, "microelectronic workpiece" refers generally to an object that is processed according to the present invention. A microelectronic workpiece may include any material portion or structure of a device, particularly a semiconductor or other electronic device, and may be a base substrate structure, such as a semiconductor substrate or layer on or overlying a base substrate structure, such as a thin film. Thus, it is not intended to limit the workpiece to any particular base structure, underlying layer, or overlying layer, patterned or unpatterned, but rather is intended to include any such layer or base structure and any combination of layers and / or base structures. Although the following description may refer to a particular type of substrate, this description is for illustrative purposes only and not for limiting purposes.

[0080] As used herein, the term "substrate" means and includes a base material or structure on which a material is formed. It will be understood that a substrate may include a single material, multiple layers of different materials, a layer or layers having regions of different materials or structures therein, and the like. These materials may include semiconductors, insulators, conductors, or combinations thereof. For example, the substrate may be a semiconductor substrate, a base semiconductor layer on a supporting structure, a metal electrode, or a semiconductor substrate having one or more layers, structures, or regions formed thereon. The substrate may be a conventional silicon substrate or other bulk substrate that includes a layer of a semiconducting material. As used herein, the term "bulk substrate" means and includes not only silicon wafers, but also silicon-on-insulator ("SOI") substrates, such as silicon-on-sapphire ("SOS") substrates, silicon-on-glass ("SOG") substrates, epitaxial layers of silicon on a base semiconductor foundation, and the like, and other semiconductor or optoelectronic materials, such as silicon germanium, germanium, gallium arsenide, gallium nitride, and indium phosphide, and the like. The substrate may or may not be doped with impurities.

[0081] Systems and methods for processing microelectronic workpieces have been described in various embodiments. Those skilled in the art will recognize that the various embodiments can be practiced without one or more of the specific details or with other alternative and / or additional methods, materials, or elements. In other instances, well-known structures, materials, or operations have not been shown or described in detail to avoid obscuring aspects of the various embodiments of the invention. Similarly, for purposes of explanation, specific values, materials, and configurations are set forth to provide a thorough understanding of the invention. However, the invention may be practiced without the specific details. Additionally, it should be understood that the various embodiments shown in the figures are representations for illustrative purposes and are not necessarily drawn to scale.

[0082] Further modifications and alternative embodiments of the described systems and methods will be apparent to those skilled in the art from this description. It will therefore be appreciated that the described systems and methods are not limited to these exemplary configurations. It should be understood that the forms of the systems and methods shown herein should be construed as being given as exemplary embodiments. Various modifications to the implementations may be made. Thus, while the present invention has been described with respect to specific embodiments, various improvements and modifications may be made without departing from the scope of the present invention. Thus, the present specification and figures should be construed in an illustrative, rather than restrictive, sense, and such improvements are intended to be included within the scope of the present invention. Furthermore, any advantages, benefits or solutions to problems described herein with respect to specific embodiments are not intended to be construed as essential, required or essential features or elements of any or all elements of the claims.

Claims

1. 1. A method of dispensing liquid for a microelectronic workpiece processing system, comprising: receiving a liquid to be dispensed in a dispensing system including a pump for pressurizing the liquid and a flow sensor disposed between the pump and a microelectronic workpiece to be processed; causing a flow change event of the liquid in the dispensing system, the causing of the liquid flow change event comprising applying pressure to the liquid in the dispensing system with the pump; sensing with the flow sensor a flow rate of the liquid after inducing the flow change event; determining one or more conditions within the dispensing system based on a delay between the application of the pressure and a change in flow rate measured by the flow sensor; The method comprising:

2. The method of claim 1 , wherein the one or more conditions include at least one of an air bubble in the dispensing system, a condition of a filter in the dispensing system, or a change in viscosity of the liquid.

3. 10. The method of claim 1, wherein the flow change event comprises opening a valve to allow flow of the liquid within the dispensing system, and wherein the determining comprises determining one or more conditions within the dispensing system based on a delay between the opening of the valve and a change in flow rate.

4. The method of claim 3 , wherein the one or more conditions include at least one of an air bubble in the dispensing system, a condition of a filter in the dispensing system, or a change in viscosity of the liquid.

5. The method of claim 1 , wherein the one or more conditions include at least one of an air bubble in the dispensing system, a condition of a filter in the dispensing system, or a change in viscosity of the liquid.

6. The method of claim 1 , wherein the one or more conditions include a condition associated with recharging a pump.

7. 10. The method of claim 1, further comprising sensing pressure in the liquid, and wherein determining one or more conditions within the dispensing system based on a delay between the application of the pressure and a change in flow rate is performed utilizing flow rate information and pressure information.

8. 1. A method of dispensing liquid for a microelectronic workpiece processing system, comprising: receiving a liquid to be dispensed in a dispensing system comprising a pump, a flow sensor disposed between the pump and a microelectronic workpiece to be processed, and a mixer disposed between the flow sensor and the microelectronic workpiece; applying pressure to the liquid in the dispensing system with the pump; dispensing the liquid onto a microelectronic workpiece; rotating the microelectronic workpiece at a spin speed during said dispensing; sensing a flow rate of the liquid during the dispense with the flow sensor; applying one or more process models to adjust at least one of the pressure, the flow rate, or the spin speed to achieve target parameters; having moreover, mixing the liquid with one or more solvents to produce a solvent concentration in the liquid prior to said dispensing; adjusting the mixing of the liquid with one or more solvents based on the process model; The method comprising:

9. The method of claim 8 , wherein the one or more processing models are one or more court simulation models.

10. The method of claim 8 , wherein the target parameters include a thickness of the coat and / or a uniformity of the coat.

11. 1. A system for dispensing liquid for a microelectronic workpiece processing system, comprising: a pump coupled to receive the liquid to be dispensed; a nozzle coupled to receive the liquid from the pump and to dispense the liquid onto a microelectronic workpiece; a pressure sensor coupled to sense pressure in the liquid; a flow sensor coupled to sense a flow rate of the liquid; a substrate holder for said microelectronic workpiece; a spin motor coupled to rotate the substrate holder at a spin speed; a controller coupled to receive pressure information from the pressure sensor, flow rate information from the flow sensor, and spin speed information from the spin motor; Including, The system further comprises a mixer configured to mix the liquid with one or more solvents; the pressure sensor is coupled between the pump and the nozzle, the flow sensor is coupled between the pressure sensor and the nozzle, and the mixer is coupled between the flow sensor and the nozzle; The system, wherein the controller is configured to adjust solvent mixing by the mixer and at least one of the pressure, the flow rate, or the spin speed based on one or more process models to achieve target parameters.

12. The system of claim 11 , wherein the pump includes a hydraulic pump having a piston controlled by the controller, and a displacement reading from the hydraulic pump is used as the pressure sensor.

13. The system of claim 11 , wherein the target parameters include a thickness of the coat and / or a uniformity of the coat.

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