Liquid dispensing system, device and method

Abstract

A liquid dispensing system (100, 200, 300), comprising: at least one nozzle (110) designed to dispense a liquid; at least one sensor module (120) configured to provide a sensor signal that includes information relating to whether liquid is being dispensed through the at least one nozzle (110); and at least one electromagnetic emitter module (122) configured to emit electromagnetic radiation in the direction of a falling path of liquid, which is discharged through the at least one nozzle (110), wherein at least part of the at least one sensor module (120) is arranged near the nozzle (110), wherein at least one sensor module (120) is configured to provide the sensor signal based on an influence of the dispensed liquid on the electromagnetic radiation, wherein at least one sensor module (120) is configured to determine the sensor signal based on a refraction of the emitted electromagnetic radiation caused by the dispensed liquid, wherein a portion of the electromagnetic radiation emitted by the at least one electromagnetic emitter module (122) and received by the at least one sensor module (120) while liquid is dispensed through the at least one nozzle (110) is at least 10% higher than a portion of the electromagnetic radiation emitted by the at least one electromagnetic emitter module (122) and received by the at least one sensor module (120) while no liquid is dispensed through the at least one nozzle (110).

Description

Technical field

[0001] Exemplary embodiments relate to concepts for a liquid dispensing system and in particular to a liquid dispensing system, a device for providing a control signal for a liquid dispensing system and a method for providing a control signal for a liquid dispensing system. background

[0002] Dispensing liquids is a key processing step in many chemical and chemo-mechanical applications. In many cases, it can be important to dispense a precise amount of liquid or to prevent cross-contamination, for example, between processing steps. Some approaches rely on check valves to prevent liquid dripping after a liquid flow through a nozzle is stopped.

[0003] For example, German patent application DE 10 2005 010 847 A1 relates to a method and a device for measuring the discharge of a liquid. Furthermore, German patent application DE 600 30 007 T2 relates to a method and a system for determining the acceptability of a fluid discharge. German patent application EP 0 222 258 A2 relates to a device for checking the discharge of fluid or semifluid products. German patent application DE 10 2014 104 996 A1 relates to a metering valve for dispensing liquid or pasty media. German patent application EP 1 946 843 A1 relates to a liquid droplet monitoring and measuring device. US patent specification 5,801,315 relates to a system for checking a liquid flow and a corresponding method. A method and a device for generating a conversion layer are known from German patent application DE 10 2007 052 ​​770. German patent application DE 25 08 927 A1 relates to a flow measuring device.Furthermore, the patent application DE 10 2015 100 395 A1 relates to a spectrometer and a fluid analysis system. Summary

[0004] There may be a need to provide an improved concept for liquid dispensing systems that enables the reduction of failures or unwanted behavior due to incorrectly dispensed liquids.

[0005] This need is met by the subject matter of the independent claims. Further aspects are contained in the dependent claims, the figures, and the following description.

[0006] Some embodiments relate to a liquid dispensing system. The liquid dispensing system comprises at least one nozzle configured to dispense a liquid. The liquid dispensing system comprises at least one sensor module configured to provide a sensor signal containing information about whether liquid is being dispensed through the nozzle. At least one section of the at least one sensor module is located near the nozzle.

[0007] Some embodiments relate to a device for providing a control signal for a liquid dispensing system. The device comprises at least one interface configured to receive a sensor signal containing information about whether liquid is being dispensed through a nozzle of the liquid dispensing system. The device further comprises a control module configured to detect a faulty dispensing of liquid through the nozzle based on the sensor signal. The at least one interface is configured to provide a control signal based on a detected faulty dispensing of liquid through the nozzle.

[0008] Some embodiments relate to a method for providing a control signal for a liquid dispensing system. The method includes receiving a sensor signal containing information about whether a liquid is being dispensed through a nozzle of the liquid dispensing system. The method further includes detecting a faulty dispensing of liquid through the nozzle based on the sensor signal. The method further includes providing a control signal based on a detected faulty dispensing of liquid through the nozzle. Brief description of the characters

[0009] Some exemplary embodiments of devices and / or methods are described below only by way of example and with reference to the accompanying figures, in which: Fig. 1 shows a schematic cross-section of a liquid dispensing system; Fig. Figure 2 shows a schematic cross-section of a liquid dispensing system comprising an electromagnetic emitter module; Fig. 2a represents an example of a lensing effect caused by a released liquid; Fig. 2b shows a schematic cross-section of a sensor module; Fig. 3 shows a schematic cross-section of a liquid dispensing system comprising a housing; Fig. Figures 3a-3f show schematic representations of elements of a housing for a liquid dispensing system; Fig. 3g shows a schematic cross-section of an opening that includes three pin holes; Fig. Figures 3h-3i show schematic representations of housings for a liquid dispensing system; Fig. 4 represents a block diagram of a device for providing a control signal to a liquid dispensing system; and Fig. Figure 5 shows a flowchart of a procedure for providing a control signal for a liquid dispensing system. Detailed description

[0010] Several embodiments are now described in more detail with reference to the accompanying drawings, in which some embodiments are illustrated. For clarity, the thickness of lines, layers, and / or regions in the figures may be exaggerated.

[0011] While modifications and alternative forms of embodiments are possible, examples of such embodiments are shown in the figures and described in detail here. It is understood, however, that the intention is not to limit embodiments to the specific forms disclosed, but rather that embodiments should encompass all modifications, correspondences, and alternatives falling within the scope of the disclosure. Throughout the description of the figures, identical numbers refer to identical or similar elements.

[0012] It is understood that when an element is described as "connected" or "coupled" to another element, it may be directly connected or coupled to the other element, or intermediate elements may exist. Conversely, when an element is described as "directly" "connected" or "coupled" to another element, no intermediate elements exist. Other expressions used to describe the relationship between elements should be interpreted similarly (e.g., "between" versus "directly between," "adjacent" versus "directly adjacent," etc.).

[0013] The terminology used here is intended only to describe specific embodiments and is not meant to be limiting. According to our usage, the singular forms "ein, eine" and "das, der, die" are to include the plural forms as well, unless the context clearly indicates otherwise. Furthermore, it is understood that the terms "umfassungt," "umfassend," "aufweist," and / or "aufweisend," as used here, indicate the presence of specified features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0014] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as they are commonly understood by a person skilled in the art in the field to which the embodiments belong. Furthermore, it is understood that terms, e.g., those defined in commonly used dictionaries, should be interpreted as having a meaning corresponding to their meaning in the context of the relevant technology. However, should the present disclosure give a particular meaning to an expression that differs from a meaning commonly understood by a person skilled in the art, that meaning should be taken into account in the specific context in which that definition is given here.

[0015] Fig. Figure 1 shows a schematic cross-section of a liquid dispensing system 100. The liquid dispensing system comprises at least one nozzle 110 configured to dispense a liquid. The liquid dispensing system further comprises at least one sensor module 120 configured to provide a sensor signal containing information about whether liquid is being dispensed through the nozzle. At least a portion of the at least one sensor module 120 is located near the nozzle.

[0016] The sensor signal can be used to detect liquid dripping from deactivated nozzles, enabling the detection of defects in a manufacturing process (e.g., wafer fabrication) during production. Early detection of dripping allows for appropriate steps to be taken to prevent contamination of subsequent processing materials. Furthermore, the sensor signal can be used to monitor liquid flow, for example, to detect positive or negative deviations from a planned quantity of liquid to be dispensed. For instance, the quantity of liquid (to be dispensed) could refer to a time period over which the liquid is dispensed and / or a volume of liquid dispensed per unit of time.

[0017] The liquid dispensing system 100 can correspond to a liquid dispensing system of a chemical or chemo-mechanical manufacturing system. For example, the liquid dispensing system 100 can correspond to a liquid dispensing system of a semiconductor wafer manufacturing system. For example, the liquid dispensing system 100 can be configured to dispense at least one liquid for chemical or chemo-mechanical processing. For example, the liquid dispensing system can further comprise at least one liquid tank suitable for storing the at least one liquid. For example, the liquid dispensing system can further comprise at least one valve configured to control the flow of the at least one liquid. For example, the liquid dispensing system can further comprise at least one backflow preventer valve configured to draw back any remaining fluid after the at least one backflow preventer valve has closed.

[0018] For example, the at least one nozzle 110 may have a tube or hose. The at least one nozzle 110 may be configured to direct or modify the flow of the at least one liquid. For example, a first inner diameter of the nozzle at a first opening of the nozzle may be at least 10% larger than a second inner diameter of the nozzle at a second opening of the nozzle. For example, the nozzle 110 may be mounted vertically on a valve of the liquid dispensing system 100. For example, the at least one nozzle 110 may be arranged below at least one valve of the liquid dispensing system 100. For example, an outlet opening (lower opening) of the at least one nozzle may have an inner diameter of less than 2 cm (or less than 1 cm, less than 8 mm, less than 6 mm, less than 5 mm, less than 4 mm, less than 3 mm, or less than 2 mm).For example, at least one nozzle can be configured to dispense less than 2 liters of liquid per hour (1 / h) (or less than 31 / h, less than 51 / h, less than 101 / h). For example, the liquid dispensing system 100 can have at least two nozzles. A first nozzle of the at least two nozzles can be configured to dispense a first liquid, and a second nozzle of the at least two nozzles can be configured to dispense a second liquid that is different from the first liquid. For example, the at least two nozzles can be configured to dispense at least two different liquids. For example, the liquid dispensing system can have two or more nozzles 110 and two or more sensors 120 configured to provide the sensor signal, which includes information relating to whether the liquid is being dispensed through the two or more nozzles.

[0019] For example, the liquid could be an acid or solvent, such as sulfuric acid (H₂SO₄), nitric acid (HNO₃), or hydrofluoric acid (HF). For example, the liquid could be a photoresist, such as polymethyl methacrylate (PMMA), polymethyl glutarimide (PMGI), phenol-formaldehyde resin (diazonaphthoquinone (DNQ) / Novolak), SU-8, or OSTE polymers (off-stoichiometry thiol-enes polymers). For example, the liquid could be a fluid used in chemical or chemo-mechanical processing.

[0020] For example, at least one sensor module 120 can have a receiver component (e.g. a sensor) and an emitter component (e.g. an electromagnetic or sound emitter).

[0021] For example, at least one sensor module 120 can be configured to measure electromagnetic radiation, e.g., the intensity or power of the electromagnetic radiation. For example, at least one sensor module 120 can include at least one optical sensor, e.g., an electro-optical sensor. The optical sensor can be used to detect the flow of liquid from the nozzle and can enable the detection of the liquid by refraction or absorption of light, for example. The optical sensor can be configured to generate the sensor signal based on light received after an interaction with liquid discharged through the at least one nozzle (e.g., after passing through or crossing a path along which liquid discharged through the at least one nozzle falls).For example, the interaction can be a refraction or reflection of light caused by the liquid being dispensed through the at least one nozzle. The sensor signal can contain optical sensor information. For example, the at least one optical sensor can be configured to measure a physical quantity of the light striking the optical sensor and to provide the sensor signal based on that physical quantity. For example, a first physical quantity of the light can be higher when liquid is dispensed through the at least one nozzle than a second physical quantity of the light when no liquid is dispensed through the at least one nozzle. For example, the at least one optical sensor can be configured to determine the sensor signal based on a refraction or reflection of light caused by the liquid (the medium).For example, at least one sensor module 120 can be configured to measure the intensity of light (or electromagnetic radiation) striking the at least one sensor module 120 (e.g., the at least one optical sensor) for the sensor signal. For example, the optical sensor can comprise at least one photoconductor module, one photovoltaic module, one photodiode, or one phototransistor.

[0022] For example, the at least one sensor module can further comprise one or more optical fibers. For example, one end of each of the one or more optical fibers can be located near the nozzle. For example, at least a subset of the one or more optical fibers (receiver fibers) can be coupled to the at least one optical sensor (photodetector). For example, another subset of the one or more optical fibers (emitter fibers) can be coupled to an electromagnetic emitter module, e.g., a light emitter module. For example, the at least one optical sensor and the electromagnetic emitter module can be located farther away from the at least one nozzle than one end of the one or more optical fibers.For example, a subset of the one or more optical fibers can be configured to carry light emitted by the electromagnetic emitter module (light emitter module) along a path of liquid emitted through the at least one nozzle. For example, another subset of the one or more optical fibers can be configured to carry light reflected or refracted by the liquid emitted through the at least one nozzle toward the optical sensor. For example, the optical sensor and / or the emitter module can be located at a distance of at least 10 cm (or at least 20 cm, at least 30 cm, at least 50 cm) from the at least one nozzle. For example, the optical sensor and / or the emitter module can be located outside a chemically resistant housing of the at least one sensor module.

[0023] For example, at least one sensor module 120 may include an image generation sensor (camera sensor) designed to convert light or other electromagnetic radiation influenced by the dispensed liquid into electronic signals and to provide the sensor signal based on the converted light or other electromagnetic radiation.

[0024] For example, the liquid dispensing system (e.g., the at least one sensor module) can further comprise at least one acoustic emitter module configured to emit ultrasound. The at least one sensor module 120 can be configured to generate the sensor signal based on the influence of the dispensed liquid on the ultrasound. The at least one acoustic emitter module can be configured to emit ultrasound at a frequency of, for example, between 20 kHz (or 50 kHz, 100 kHz, 1 MHz, 100 MHz) and 5 GHz (or 1 GHz, 500 MHz, 200 MHz). Utilizing the ultrasound range can enable the use of available sensor modules and analysis techniques. The at least one sensor module 120 can be configured to measure the ultrasound transmitted by the at least one acoustic emitter module and influenced by the dispensed liquid.

[0025] For example, the at least one sensor module 120 can include an inductive sensor, e.g., a field sensor. The at least one sensor module 120 can be configured to induce eddy currents in the liquid dispensed through the at least one nozzle; for example, the at least one sensor module 120 can include an induction loop configured to emit eddy currents. The at least one sensor module 120 can be configured to generate the sensor signal based on the intensity of eddy currents induced in the dispensed liquid. For example, a field sensor of the at least one sensor module 120 can be configured to detect a change in the inductance of the induction loop caused by the dispensed liquid. Using eddy currents to determine the sensor signal can enable inductive measurement of the liquid dispensing.

[0026] For example, at least one sensor module 120 can be a capacitive sensor module. At least one sensor module 120 can be configured to generate the sensor signal based on a capacitance formed between the passing liquid and the sensor module 120, for example.

[0027] For example, the sensor signal can contain analog or digital sensor information. For instance, the sensor signal can be proportional to electromagnetic radiation measured by the at least one sensor module. For example, the at least one sensor module 120 can be configured to convert an analog signal measured by a sensor, such as an optical or inductive sensor, into a digital representation of the analog signal measured by the sensor. The sensor signal can contain the digital representation of the analog signal, for example, as digital bit values ​​according to a specified code. For example, the sensor signal can contain the analog signal or a transformation of the analog signal. The sensor signal can be, for example, an electronic signal, an optical signal, or a radio signal.

[0028] For example, the liquid dispensing system 100 can further comprise at least one interface configured for transmitting the sensor signal provided by the at least one sensor module 120. The at least one interface can correspond to one or more inputs and / or outputs for receiving and / or transmitting information, which may be in digital (bit) values ​​according to a specified code, within a module, between modules, or between modules of different entities.

[0029] The information relating to whether the liquid is dispensed through the at least one nozzle may include information relating to at least a quantity (e.g., information relating to the duration of a time period during which the liquid is dispensed and / or information relating to a volume of liquid dispensed per unit of time) of liquid dispensed through the at least one nozzle, an influence of the liquid dispensed through the at least one nozzle on electromagnetic radiation (e.g., light) or ultrasound measured by the at least one sensor module, an intensity of sound waves, electromagnetic radiation (e.g., light), or ultrasound influenced by the dispensed liquid, a refraction of electromagnetic radiation (e.g., light) or ultrasound influenced by the dispensed liquid, and a drop of liquid from the at least one nozzle.

[0030] For example, at least part of the at least one sensor module 120 can be located near the liquid dispensed through the nozzle. For example, a lateral distance between part (e.g., one end of an optical fiber) of the at least one sensor module and the liquid dispensed through the at least one nozzle can be less than 5 cm (or less than 4 cm, less than 3 cm, less than 2 cm, less than 1 cm, or less than 5 mm). A small lateral distance can enable more precise monitoring or detection of dispensed liquid. For example, the lateral distance between the at least one sensor module and the dispensed liquid can depend on the diameter of the liquid dispensed through the at least one nozzle 110.

[0031] For example, the lateral distance between (the part of) the at least one sensor module and the at least one nozzle can be less than 5 cm (or less than 4 cm, or less than 3 cm, less than 2 cm, less than 1 cm, less than 5 mm, or less than 1 mm). For example, at least the part of the sensor module located near the nozzle can include at least one (optical) sensor or optical fiber. For example, the at least one nozzle can be located within a cavity of a housing that contains at least part of the at least one sensor module, for example.

[0032] For example, at least part of the at least one sensor module 120 can be arranged vertically below the nozzle outlet and laterally offset from a lateral center of the nozzle by at least the inner radius of the nozzle (or at least the inner radius of the nozzle plus 1 mm, plus 2 mm, plus 3 mm, plus 4 mm, plus 5 mm, plus 1 cm). For example, a vertical distance between (a part of) the at least one sensor module and the nozzle outlet can be less than 5 cm (or less than 4 cm, or less than 3 cm, less than 2 cm, less than 1 cm, less than 5 mm, or less than 1 mm).

[0033] For example, the liquid delivery system 100 can further include a support structure (e.g., a chuck or a rotating table) for holding a semiconductor wafer under the at least one nozzle. For example, a path of the delivered liquid can terminate at the semiconductor wafer. For example, a vertical distance between the support structure and the at least one nozzle 110 can be more than 10 cm (or more than 15 cm, more than 20 cm, more than 25 cm) and / or less than 50 cm (or less than 40 cm, less than 30 cm, less than 20 cm, less than 15 cm). The semiconductor wafer can be a silicon wafer. Alternatively, the semiconductor wafer can be a wideband-gap semiconductor wafer with a bandgap greater than that of silicon (1.1 eV). For example, the semiconductor wafer can be a silicon carbide (SiC) based semiconductor wafer, a gallium arsenide (GaAs) based semiconductor wafer, or a gallium nitride (GaN) based semiconductor wafer.The semiconductor wafer can have a lateral diameter greater than 100 mm (or greater than 200 mm, 290 mm, or 400 mm). The semiconductor wafer can also have a lateral diameter less than 500 mm (or less than 400 mm, 250 mm, or 180 mm). For example, the semiconductor wafer can have a lateral diameter of 150 mm, 200 mm, 300 mm, or 450 mm (e.g., ±10%).

[0034] For example, the liquid dispensing system 100 may further comprise a device for providing a control signal for the liquid dispensing system, e.g., a device 400 for providing a control signal for a liquid dispensing system, described in conjunction with Fig. 4. For example, the liquid dispensing system 100 can be configured to control an operation of the liquid dispensing system 100 or of a chemical or chemo-mechanical processing plant comprising the liquid dispensing system 100 based on the control signal. Further embodiments provide a chemical or chemo-mechanical processing plant (e.g., a centrifugal etching tool / a semiconductor wafer fabrication plant) that includes the liquid dispensing system 100.

[0035] For example, a vertical direction, a vertical distance, and a vertical dimension can be measured parallel to a local gravity vector. A lateral direction, a vertical distance, and lateral dimensions can be measured orthogonally to the vertical direction.

[0036] Fig. Figure 2 shows a diagram of a schematic cross-section of an embodiment of a liquid dispensing system 200. The liquid dispensing system 200 can be similar to the one in connection with Fig. The liquid dispensing system described in Section 1 is implemented. The liquid dispensing system can additionally include at least one electromagnetic emitter module 122 configured to emit electromagnetic radiation in the direction of a path of falling liquid dispensed through the at least one nozzle (e.g., in the direction of at least one part of the at least one sensor module). At least one sensor module 120 can be configured to provide the sensor signal based on the influence of the dispensed liquid on the electromagnetic radiation. For example, the at least one sensor module can include the at least one electromagnetic emitter module.

[0037] The at least one electromagnetic emitter module can enable the detection of whether the liquid is being released, e.g. by enabling a measurement of the influence of the liquid on the electromagnetic radiation by the at least one sensor module, e.g. a refraction or absorption of the electromagnetic radiation by the liquid.

[0038] For example, the at least one electromagnetic emitter module 122 can include at least one light emitter module configured to emit light. The at least one electromagnetic emitter module 122 can be configured to emit light with a wavelength between 100 nm and 100 µm, for example. Using the (visible) light range can enable the use of available sensor modules and can facilitate analysis of the sensor signal, as the influence of the liquid on the (visible) light can be readily investigated. For example, the at least one electromagnetic emitter module 122 can be configured to emit electromagnetic radiation within a visible light range, e.g., electromagnetic radiation with a wavelength between 300 nm and 800 nm. For example, the at least one electromagnetic emitter module can include at least one light-emitting diode (LED) or a laser diode.For example, at least one electromagnetic emitter module 122 can be configured to emit light (electromagnetic radiation) with a beam angle of less than 20° (or less than 15°, less than 12°, less than 10°, less than 8°, less than 5°, less than 2°).

[0039] For example, the at least one electromagnetic emitter module 122 can be configured to emit electromagnetic radiation at a wavelength where more than 30% (or more than 40%, more than 50%, more than 60%, more than 70%, more than 80%, more than 90%) of a portion of the electromagnetic radiation striking the liquid discharged through the at least one nozzle passes through the liquid. For example, the at least one electromagnetic emitter module 122 can be configured to emit electromagnetic radiation at a wavelength where less than 70% (or less than 60%, less than 50%, less than 40%, less than 30%, less than 20%, less than 10%) of a portion of the electromagnetic radiation striking the liquid discharged through the at least one nozzle is absorbed or reflected by the liquid.Using electromagnetic radiation at a wavelength where the electromagnetic radiation is only partially absorbed by the liquid allows the use of refraction to determine whether the liquid is dispensed, while remaining independent of any changes in the liquid's absorption behavior. For example, the at least one electromagnetic emitter module 122 can be configured to emit electromagnetic radiation based on physical properties (e.g., refraction, attenuation, or reflection) of the liquid, which is then dispensed through the at least one nozzle.

[0040] For example, the liquid dispensing system 200 can further comprise at least one opening 130. An opening structure 130a can, for example, comprise at least one opening 130. The opening can enable a more defined propagation of the electromagnetic radiation and can allow the measurement of a more pronounced difference between a liquid being dispensed and the case when no liquid is dispensed. The at least one opening 130 can be configured to shield the at least one sensor module 120 from at least a portion of the electromagnetic radiation emitted by the at least one electromagnetic emitter module 122. The at least one opening 130 can be configured to narrow the beam angle of the electromagnetic radiation emitted by the at least one electromagnetic emitter module 122, for example.Due to the narrower beam angle, the positioning of the at least one sensor module 120 and the at least one electromagnetic emitter module can be less sensitive to misalignment. The at least one opening 130 can have a pinhole opening (circular opening) or a slot opening, for example. The opening structure 130a can correspond to a cuboid shape, encompassing the at least one opening 130. The opening structure 130a can be contained in and be part of a housing of the liquid dispensing system, for example. The at least one opening 130 can have a void or be made of a transparent or semi-transparent material.The opening structure 130a comprising the at least one opening can be configured to absorb or reflect the electromagnetic radiation emitted by the at least one electromagnetic emitter module 122, apart from the electromagnetic radiation emitted by the at least one opening 130, for example. For instance, the at least one opening can be made of a semi-transparent material. The semi-transparent material can shield the at least one electromagnetic emitter module 122 from the liquid and prevent liquid deposition within the at least one opening. Alternatively, a semi-transparent housing can contain the at least one electromagnetic emitter module 122 and the opening structure comprising the at least one opening 130.The at least one opening can have an inner diameter of less than 1 cm (or less than 5 mm, less than 4 mm, less than 3 mm, less than 2 mm). The opening can have a minimum width of less than 10 mm (or less than 5 mm, less than 4 mm, less than 3 mm, or less than 2 mm) and more than 0.4 mm (more than 0.5 mm, more than 1 mm, more than 2 mm, more than 4 mm), for example. The width (inner diameter) of the at least one opening can define an angled beam of the electromagnetic radiation beam that crosses the at least one opening. For example, the width (inner diameter) of the at least one opening can depend on the diameter of a flow of liquid discharged through the at least one nozzle and / or on a distance between the flow of liquid, the at least one opening, and the at least one sensor module 120, for example.For example, a lateral distance between the at least one aperture 130 (or the aperture structure) and the emitted liquid can be less than 2 cm (or less than 1 cm or less than 5 mm). A small lateral distance between the aperture and the emitted liquid can allow a more concentrated stream of electromagnetic radiation upon impact with the liquid. For example, a lateral distance between the at least one electromagnetic emitter module 122 and the at least one aperture 130 can be less than 5 cm (or less than 2 cm, less than 1 cm, or less than 5 mm). For example, the distance between the at least one aperture and the emitted liquid can depend on a refractive index of the emitted liquid and / or on a lateral length and an inner diameter of the at least one aperture 130, for example.

[0041] For example, the at least one sensor module 120 can be configured to determine the sensor signal based on the refraction (or diffraction) of the emitted electromagnetic radiation caused by the dispensed liquid. Using refraction to determine the sensor signal (comprising information related to whether the liquid is dispensed through the at least one nozzle) allows the at least one sensor module and the electromagnetic emitter module to be used with different liquids or with liquids that change their absorption behavior over time. For example, the dispensed liquid can act as a lens, focusing the electromagnetic radiation (light). Dispensed liquid can narrow the beam angle of the electromagnetic radiation, for example.

[0042] For example, the at least one sensor module 120 can be configured to determine the sensor signal based on a reflection of the emitted electromagnetic radiation caused by the dispensed liquid. For example, the at least one sensor module can include the at least one emitter module; for instance, the at least one sensor module can share a housing with the at least one emitter module. For example, an optical fiber coupled to an optical sensor of the at least one sensor module can be adjacent to one or more optical fibers coupled to the at least one emitter module.The at least one emitter module can be configured to emit light through the one or more optical fibers, which can be reflected by liquid dispensed through the at least one nozzle, and the optical sensor can be configured to detect light reflected by the dispensed liquid and transported through the optical fiber towards the optical sensor.

[0043] For example, a section of electromagnetic radiation emitted by the at least one electromagnetic emitter module 122, received by the at least one sensor module 120, while liquid is dispensed through the at least one nozzle, can be at least 10% (or at least 20%, at least 30% higher, at least 50%) higher (or lower) than a section of electromagnetic radiation emitted by the at least one electromagnetic emitter module 122, received by the sensor module 120, while no liquid is dispensed through the at least one nozzle, e.g. due to refraction.For example, a first section of electromagnetic radiation emitted by the at least one electromagnetic emitter module 122, received by the at least one sensor module 120, while liquid is dispensed through the at least one nozzle, can be at least 10% higher (or at least 20% higher, at least 50% higher) than a second section of electromagnetic radiation emitted by the at least one electromagnetic emitter module 122, received by the at least one sensor module 120, while no liquid is dispensed through the at least one nozzle.For example, a first section of electromagnetic radiation emitted by the at least one electromagnetic emitter module 122, received by the at least one sensor module 120, while liquid is dispensed through the at least one nozzle, can be at least 10% lower (or at least 20% lower, at least 50% lower) than a second section of electromagnetic radiation emitted by the at least one electromagnetic emitter module 122, received by the at least one sensor module 120, while no liquid is dispensed through the at least one nozzle.For example, (an inner diameter or location of) the at least one opening 130, (a size or location of) the at least one sensor module 120 and / or (a beam angle or location) the at least one electromagnetic emitter module 122 can be arranged and configured such that a first section of the electromagnetic radiation emitted by the at least one electromagnetic emitter module 122, received by the at least one sensor module 120, while liquid is dispensed through the at least one nozzle, can be at least 10% higher (or at least 20% higher, at least 50% higher) than a second section of the electromagnetic radiation emitted by the at least one electromagnetic emitter module 122, received by the at least one sensor module 120, while no liquid is dispensed through the at least one nozzle.

[0044] Fig. Figure 2a presents an example of a lensing effect caused by a released liquid. The at least one electromagnetic emitter module 122 (emitter) is configured to emit light 202 through the pinhole opening 130. The liquid 204 narrows the angle of the beam (due to refraction), resulting in a narrower beam 206 (solid lines) compared to a beam 208 that is not affected by the liquid 204 (dashed lines). The at least one sensor module 120 (detector) is configured to measure the intensity of the light 202 incident on the at least one sensor module 120, which may be higher for the narrower beam 206 than for the narrower beam 208, for example. Without an opening, there can be competition between refraction and absorption, where differences are difficult to detect and may be masked by a change, e.g., if the liquid changes color and refractive behavior over time.

[0045] Fig. Figure 2b shows a schematic cross-section of a sensor module comprising an optical fiber 210 coupled to an optical sensor of the sensor module and a plurality of optical fibers 212 coupled to at least one electromagnetic emitter module (light emitter module). The optical fibers can be bundled 214 and lead towards the optical sensor and the at least one electromagnetic emitter module. Fig. 2b can represent a dual-core (multi-core) optical fiber with a coaxial structure. One fiber can be used for the emitter (electromagnetic emitter module), and the other fiber(s) can be used for the receiver (optical sensor). For example, the optical fiber 210 coupled to the optical sensor can have a larger diameter (e.g., at least 20% larger) than the majority of optical fibers 212 coupled to the at least one electromagnetic emitter module. For example, the optical fiber 210 coupled to the optical sensor can have a diameter of approximately 0.5 mm, and the majority of optical fibers 212 coupled to the at least one electromagnetic emitter module can have a diameter of approximately 0.25 mm.

[0046] Further details and aspects of the liquid dispensing system 200 are related to the proposed concept or one or more preceding or following (e.g. Fig. 1, Fig. The liquid dispensing system 200 may have one or more additional optional features corresponding to one or more aspects of the proposed concept or to one or more of the examples described above or below.

[0047] Fig. Figure 3 shows a schematic cross-section of a liquid dispensing system 300. The liquid dispensing system 300 can be similar to one of the systems described in connection with Fig. The liquid dispensing systems described in 1-2 are implemented. The liquid dispensing system 300 comprises at least one nozzle 110 configured to dispense a liquid. The liquid dispensing system 300 further comprises at least one sensor module 120 configured to provide a sensor signal containing information about whether the liquid is being dispensed through the nozzle. The liquid dispensing system 300 further comprises a housing 140 for the at least one sensor module 120. The housing 140 is chemically resistant to at least one of the acids sulfuric acid, nitric acid, and hydrofluoric acid. The housing can shield the at least one sensor module and / or the at least one electromagnetic emitter module, for example.

[0048] Chemical resistance can be defined according to standards ISO 2812, e.g., ISO 2812-1:2007 and ISO 2812-4:2007 of the International Organization for Standardization (ISO). Chemical resistance can be based on visual inspection after prolonged immersion of the material in a liquid (e.g., sulfuric acid, nitric acid, or hydrofluoric acid) or after spotting, for example. The housing can be chemically resistant if prolonged immersion or spotting of the housing 140 in / with sulfuric acid, nitric acid, and / or hydrofluoric acid results in no or only a slight change (intensity of change 0 or 1 according to ISO standard ISO 4628-1 to -5) of the housing 140. The housing can be made of a fluoroelastomer (FKM), e.g., Viton or Viton B, for example. The housing can also be made of polyvinylidene fluoride (PVDF) or polytetrafluoroethylene (PTFE, Teflon), for example.

[0049] For example, the housing can enable a chemically resistant device (e.g., resistant to H₂SO₄ (sulfuric acid), HNO₃ (nitric acid), HF (hydrofluoric acid), etc.). The housing can have small dimensions for "plugging in" into an existing setup. The housing can have a smooth surface to remain within defect density requirements and prevent droplet adhesion. The housing can be a closed, semi-transparent enclosure for reduced defect density and prevention of droplet adhesion.

[0050] The housing can be designed to protect the at least one sensor module 120 from the liquid dispensed through the at least one nozzle, for example. The housing can be designed to protect the at least one electromagnetic emitter module (e.g., at least one electromagnetic emitter module 122, which is used in conjunction with Fig. 2) to protect from the liquid dispensed through the at least one nozzle, for example. The housing can be transparent or semi-transparent, for example. For example, at least a part of the housing 140 can be made of a semi-transparent material, e.g., parts of the housing arranged between the at least one sensor module 120 and the at least one electromagnetic emitter module 122. At least a part of the housing 140 arranged between at least one of the electromagnetic emitter modules 122 or the sensor module 120 and a path of fall of the dispensed liquid can be made of a semi-transparent material. The semi-transparent material can provide protection for the at least one sensor module and / or the at least one electromagnetic emitter module while maintaining functionality.Semi-transparency can refer to at least partial transparency of at least part of the housing in the direction of (visible) light, or to at least partial transparency of at least part of the housing in the direction of (other) electromagnetic radiation.

[0051] The at least one nozzle 110 can be arranged within a void contained in the housing, for example. For example, the housing 140 can be attached to a dispensing structure of the liquid dispensing system 300, which has the at least one nozzle 110.

[0052] For example, the housing 140 can have or contain at least one sensor module 120. For example, at least one section of the at least one sensor module 120 can extend from the housing 140 (e.g., protrude). For example, at least sections of a wiring structure of the at least one sensor module 120 can be located in the housing 140. The housing 140 can have cavities, e.g., a cavity for arranging fasteners (e.g., screws), a cavity for inserting the at least one sensor module 120 or the at least one electromagnetic emitter module, and / or a cavity containing the at least one nozzle 110.

[0053] For example, the liquid dispensing system 300 can have an opening structure 130a, which has at least one opening 130. The housing 140 can have the opening structure 130a, for example. Alternatively, the housing 140 can have the at least one opening 130. For example, the opening carrier can be made of a non-transparent material. The opening structure 130a can be configured to shield the at least one sensor module 120 from at least part of the electromagnetic radiation emitted by the electromagnetic emitter module 122, for example.

[0054] Fig. Figure 3a shows a schematic diagram of a housing 140 according to an exemplary embodiment. The housing comprises a first substructure 302 and a second substructure 304. The housing 140 further comprises a first plurality of lateral fastening elements 306, a second plurality of lateral fastening elements 308, and a first plurality of vertical fastening elements 310. The housing further comprises an opening structure 130a comprising at least one opening (130, as shown in Figure 3a). Fig. 3f shown).

[0055] The first plural of lateral fasteners 306, the second plural of lateral fasteners 308, and / or the first plural of vertical fasteners 110 may have two or more screws, e.g., hexagon head screws, slotted screws, or headless screws. A thread of the first plural of lateral fasteners 306, the second plural of lateral fasteners 308, and / or the first plural of vertical fasteners 110 may have a diameter greater than 1 mm (or greater than 2 mm, greater than 5 mm, greater than 10 mm, greater than 15 mm), for example. The thread of the first plural of lateral fasteners 306, the second plural of lateral fasteners 308, and / or the first plural of vertical fasteners 110 may have a diameter less than 20 mm (or less than 15 mm, less than 10 mm, less than 5 mm), for example.The thread length of the first plural of lateral fasteners 306, the second plural of lateral fasteners 308 and / or the first plural of vertical fasteners 110 can be greater than 10 mm (or greater than 20 mm, greater than 50 mm, greater than 100 mm), for example. The thread length of the first plural of lateral fasteners 306, the second plural of lateral fasteners 308 and / or the first plural of vertical fasteners 110 can be less than 100 mm (or less than 50 mm, less than 20 mm, less than 10 mm), for example.

[0056] The first plurality of lateral fastening elements 306 can be configured to attach the first substructure 302 to a substructure of the liquid dispensing system that has at least one nozzle. The first plurality of vertical fastening elements 310 can connect the first and second substructures 302; 304 (e.g., force-fit), for example.

[0057] Fig. Figure 3b shows another schematic diagram of a housing 140 according to an exemplary embodiment. Fig. 3b further represents a position of a substructure of the liquid delivery system, which has at least one nozzle 110. Fig. 3b and Fig. 3d shows further perspectives of a schematic diagram of a housing 140 according to an exemplary embodiment.

[0058] For example, the lateral width / length of the enclosure can be less than 10cm (or less than 8cm, less than 5cm, or less than 3cm). The vertical height of the enclosure can be less than 15cm (or less than 10cm, less than 10cm, or less than 5cm).

[0059] Fig. Figure 3e presents schematic diagrams of an embodiment of the first substructure 302. Fig. Figure 3e comprises a schematic top view, a schematic cross-section, and a schematic 3D view of the first substructure 302. The first substructure 302 may have voids (holes) 312; 316 for a wiring structure for the at least one sensor module 120 (316) and / or a wiring structure for the at least one electromagnetic emitter module 122 (312), for example. The first substructure 302 may further have voids (holes) 314 for the first plurality of vertical fasteners 310, for example. The first substructure 302 may further have voids (holes) 306a; 308a for the first and second lateral fasteners 306; 308, for example.

[0060] Fig. Figure 3f presents schematic diagrams of an embodiment of the second substructure 304. Fig. Figure 3f includes a schematic top view, a schematic cross-section, and a schematic 3D view of the second substructure 304. The second substructure includes at least one void (hole) 318, configured to accommodate the at least one electromagnetic emitter module 122 and at least one light / electromagnetic radiation channel 318a; configured to allow propagation of the electromagnetic radiation emitted by the at least one electromagnetic emitter module 122. The at least one light / electromagnetic radiation channel 318a may be closed in the direction of the at least one nozzle 110, e.g., to prevent the liquid from entering the at least one light / electromagnetic radiation channel 318a. The second substructure may be made of a transparent or semi-transparent material, for example.The second substructure 304 may further comprise a cuboid-shaped cavity 320 for the opening structure 130a, which has at least one opening 130. The second substructure 304 may further comprise mounting holes 320a for the opening structure 130a, for example. The second substructure 304 may have a lateral length of less than 100 mm (or less than 50 mm, less than 40 mm, less than 35 mm, less than 20 mm, less than 10 mm) and a lateral width of less than 50 mm (less than 30 mm, less than 20 mm). The at least one light / electromagnetic radiation shaft 318a may have a lateral width of less than 10 mm (or less than 5 mm, less than 4 mm, less than 3 mm).The at least one cavity 318, configured to accommodate the at least one electromagnetic emitter module 122, can be round, rectangular, or a more complex (composite) shape and can have a lateral width of less than 100 mm (or less than 50 mm, less than 40 mm, less than 30 mm, or less than 20 mm). For example, the liquid dispensing system can have two or more nozzles and a housing that includes a second substructure having two or more cavities for two or more electromagnetic emitter modules. A first distance between the centers of the two or more nozzles can be substantially equal (e.g., ±10%) to a second distance between the centers of the two or more cavities, for example. The first distance and the second distance can be greater than 5mm (or greater than 8mm, greater than 10mm, greater than 20mm) and / or less than 100mm (less than 80mm, less than 50mm, less than 25mm).

[0061] Fig. Figure 3g presents schematic diagrams of an embodiment of the opening structure 130a, which has at least one opening 130. Fig. Figure 3f comprises a schematic top view, a schematic cross-section, and a schematic 3D view of the opening structure 130a. The opening structure 130a can have a lateral width of less than 10 mm (or less than 5 mm, less than 4 mm, less than 3 mm, or less than 2 mm), for example. The opening structure can have two or more openings. A distance between the centers of the two or more openings can be substantially equal (e.g., ±10%) to a first and second distance, which is related to… Fig. 3f is described.

[0062] For example, the lateral length of an object can be its greatest lateral extent. The vertical height of an object can be its greatest vertical extent. The lateral width of an object can be its lateral extent perpendicular to its greatest lateral extent.

[0063] Fig. Figure 3h shows a schematic diagram of an embodiment of a housing 140. The housing includes holes (voids) 322; 324 for the at least one sensor module 120 and the at least one electromagnetic emitter module 122. The housing 140 can be clamped to a substructure 326 of the liquid dispensing system 300, which has the at least one nozzle 110.

[0064] Fig. Figure 3i shows a schematic diagram of another embodiment of a liquid dispensing system comprising a housing. A media dispensing system with all three sensors in a chemically resistant housing can look like this. Fig. 3i. The housing comprises substructures 328; 330 for the at least one sensor module and the at least one electromagnetic emitter module 122. The housing 140 can be attached to a substructure 326 of the liquid dispensing system 300, which has the at least one nozzle 110.

[0065] Further details and aspects of the liquid dispensing system 300 are described in connection with the proposed concept or one or more preceding or following (e.g. Fig. 1-2a, Fig. The liquid dispensing system 300 may have one or more additional optional features that correspond to one or more aspects of the proposed concept or to one or more of the examples described above or below.

[0066] Fig. Figure 4 shows a block diagram of a device 400 for providing a control signal to a liquid dispensing system. The device includes at least one interface 410 configured to receive a sensor signal containing information about whether liquid is being dispensed through a nozzle of the liquid dispensing system. The device further includes a control module 420 configured to detect a faulty dispensing of liquid through the nozzle based on the sensor signal. The at least one interface 410 is configured to provide a control signal based on a detected faulty dispensing of liquid through the nozzle. For example, the at least one interface 410 can be configured to receive a status signal containing information about the activation of the nozzle of the liquid dispensing system.

[0067] The device can be configured to detect liquid dripping from deactivated nozzles, enabling the detection of defects in a manufacturing process (e.g., wafer fabrication) during production. Early detection of dripping allows for appropriate steps to be taken to prevent contamination of subsequent processing materials. Furthermore, the sensor signal can be used to monitor liquid flow, for example, to detect positive or negative deviations from a planned quantity (e.g., duration or volume) of liquid to be dispensed.

[0068] The faulty dispensing of liquid through the nozzle can correspond to a drop from the nozzle, the dispensing of liquid when the nozzle is deactivated, or the dispensing of a quantity of liquid where the quantity is below a (lower) size threshold or above a (upper) size threshold, for example.

[0069] For example, the control module 420 can further be configured to detect whether liquid is being dispensed through the nozzle, based on the sensor signal. The control module 420 can further be configured to determine information relating to a mismatch between whether liquid is being dispensed through the nozzle and information related to nozzle activation. The information related to nozzle activation can indicate whether the nozzle (or a media valve coupled to the nozzle) is turned on or off. For example, the information related to nozzle activation can indicate activation / deactivation or an open / closed state of a liquid dispensing valve for the nozzle. The control module 420 can be configured to detect a faulty dispensing of liquid through the nozzle, based on the information related to the mismatch (e.g.,(if there is a mismatch between whether the liquid is dispensed and whether the nozzle is activated).

[0070] For example, the control module 420 can be configured to detect a spike (e.g., a temporary deviation within at least one subcomponent of the sensor signal of at least 10% (or at least 20% or at least 50%) from an average value of the subcomponent) within the sensor signal to detect whether liquid is being dispensed through the nozzle, e.g., to detect faulty dispensing of liquid through the nozzle (e.g., nozzle dripping). For example, the device 400 can have a data structure that includes one or more reference values ​​for the sensor signal or subcomponents of the sensor signal. The control module 420 can further be configured to obtain one or more reference values ​​via the interface 410, for example. Alternatively, the control module 420 can be configured to determine the one or more reference values, e.g., during a calibration phase.The 420 control module can be configured to detect whether liquid is being dispensed (erroneously) based on a comparison between the sensor signal or components thereof and reference values. For example, the reference values ​​may contain information related to an (average, maximum, or minimum) value (e.g., energy, current, voltage, intensity) measured by a sensor, encompassing the sensor signal when liquid is being dispensed through the nozzle, and / or information related to an (average, maximum, or minimum) value measured by the sensor when no liquid is being dispensed. The 420 control module can then be configured to compare these reference values ​​with a corresponding current value contained in the sensor signal to detect whether liquid is being dispensed (erroneously).

[0071] For example, the sensor signal can contain information relating to electromagnetic radiation measured by a sensor module. The control module 420 can be configured to compare the intensity level of the electromagnetic radiation, measured by the at least one sensor module, with an intensity threshold to detect whether the liquid is being (faultily) dispensed through the nozzle. Using the information related to the electromagnetic radiation can enable the detection of liquid dispensing by allowing the at least one sensor module to measure the effect of the liquid on the electromagnetic radiation, such as refraction or absorption of the electromagnetic radiation by the liquid. For example, one or more reference values ​​can contain information related to the intensity threshold, for example, in joules or watts.For example, the information related to electromagnetic radiation can include information related to a current or voltage, generated by measuring the intensity of the electromagnetic radiation, and the intensity threshold can include information related to a reference current or voltage for comparison. For example, the control module 420 can be configured to determine information related to the intensity threshold (for an energy level of electromagnetic radiation measured by the at least one sensor module) based on a preceding sensor signal. The preceding sensor signal can correspond to a state or information contained within the sensor signal, measured at a previous time.For example, the control module 420 can be configured to determine an average energy level for activating and / or deactivating the nozzle based on the preceding sensor signal, and to determine the intensity threshold based on the average energy level, e.g., allowing a deviation of up to 50% (or up to 25%, up to 20%, or up to 10%).

[0072] For example, the sensor signal can contain information relating to the influence of liquid on eddy currents induced by a sensor module. The 420 control module can be configured to detect whether liquid is being (faultily) dispensed based on the liquid's influence on the eddy currents. Using eddy currents to detect liquid dispensing can enable inductive measurement of liquid dispensing. For example, the information relating to the influence of liquid on eddy currents induced by a sensor module can include information related to a current flowing through an induction loop. The 420 control module can be configured to detect whether liquid is being (faultily) dispensed based on the information related to the current flowing through the induction loop.For example, the control module 420 can be configured to detect whether liquid is being (erroneously) dispensed (e.g., drops from at least one nozzle) when the current increases by more than 10% (or more than 20% or more than 50%) compared to the current flowing through the induction loop when no liquid is being dispensed. For example, the control module 420 can be configured to determine the quantity of dispensed liquid based on a (linear) relationship between the current and the quantity of dispensed liquid, e.g., based on information related to the (linear) relationship contained in one or more reference values.

[0073] For example, the mismatch information can indicate whether there is a mismatch or a match between the dispensed (or undispensed) liquid and the information related to nozzle activation. For example, the 420 control module can be configured to determine a mismatch (e.g., detecting an erroneous dispensing of liquid) for the mismatch information when the liquid is dispensed and the nozzle activation information indicates that the nozzle is deactivated. For example, the 420 control module can be configured to determine a mismatch (e.g.,(Detection of a faulty liquid dispensing) for determining the mismatch information when liquid is not dispensed and the nozzle activation information indicates that the nozzle is activated, or when a dispensed liquid quantity is below a size threshold and the nozzle activation information indicates that the nozzle is activated. For example, the control module 420 can be configured to determine a match for the mismatch information when liquid is not dispensed and the nozzle activation information indicates that the nozzle is deactivated, or when a liquid quantity is dispensed (e.g., liquid quantity is above the size threshold) and the nozzle activation information indicates that the nozzle is activated.For example, the control module 420 can be configured to provide the control signal to cause a stop of the liquid delivery system when the information relating to a mismatch indicates a mismatch.

[0074] For example, the control module 420 can be configured to provide the control signal to trigger at least one of the following actions: a warning (e.g., a warning message in a display of a component comprising the device 400 or a log entry) or a stop of the liquid dispensing system if the sensor signal indicates that liquid is being dispensed incorrectly, e.g., if the sensor signal indicates that liquid is being dispensed and information related to nozzle activation indicates that the nozzle is deactivated. Stopping the liquid dispensing system and / or a chemical or chemo-mechanical plant when liquid is being dispensed while the nozzle is deactivated can limit consequences caused by dripping onto an actual unit being processed.For example, the control signal can have a voltage or digital bit value that indicates to the liquid dispensing system to stop dispensing the liquid. For example, the control module 420 can be configured to provide the control signal to a chemical or chemo-mechanical processing plant (e.g., a wafer manufacturing plant) to cause a stop or warning in the chemical or chemo-mechanical manufacturing plant. For example, the chemical or chemo-mechanical processing plant (or part thereof, e.g., a liquid dispensing system as in...) Fig. (1-3 discussed) must be trained to stop an operation or a delivery of fluid based on the control signal.

[0075] For example, the control module 420 can be configured to determine a quantity of liquid dispensed through the nozzle (e.g., a time period over which the liquid is dispensed or a volume of liquid dispensed) based on the sensor signal. For example, the quantity of liquid (to be dispensed) can refer to a time period over which the liquid is dispensed and / or to a volume of liquid dispensed per unit of time. The control module 420 can be configured to provide the control signal to trigger at least a warning or to stop the liquid dispensing system (or the chemical or chemo-mechanical processing plant) when information related to nozzle activation indicates that the nozzle is activated and the quantity of dispensed liquid is below a certain threshold (e.g., a time threshold or a volume threshold).Stopping the liquid dispensing system and / or the chemical or chemo-mechanical plant when the dispensed liquid volume falls below a threshold can help prevent manufacturing defects caused by insufficient liquid dispensing and can aid in the detection of sensor malfunctions. For example, one or more reference values ​​can contain information related to the size threshold. For instance, the size threshold can be more than 10% smaller (or more than 20% smaller, more than 50% smaller) than the average dispensed liquid volume. For example, the 420 control module can be configured to detect the dispensed liquid volume based on a (linear) relationship between the sensor signal, or a component of the sensor signal, and the dispensed liquid volume. The one or more reference values ​​can contain information related to this (linear) relationship, e.g.,as a formula or lookup table. For example, the sensor signal can contain information related to a current or voltage generated by a sensor module, or information related to electromagnetic radiation measured by at least one sensor module. The control module 420 can be configured to determine the amount of liquid dispensed based on a (linear) relationship between the current or voltage and the amount of liquid dispensed, e.g., based on a transformation formula or based on a lookup table.

[0076] For example, the control module 420 can be configured to determine information relating to the size threshold (for a certain amount of dispensed liquid) based on a preceding sensor signal. For example, the control module 420 can be configured to determine an average amount of dispensed liquid for nozzle activation based on the preceding sensor signal, and to determine the size threshold based on the average amount of dispensed liquid, e.g., allowing a deviation of up to 50% (or up to 25%, up to 20%, or up to 10%). For example, the control module 420 can be configured to determine the size threshold between a first value of the preceding sensor signal when the at least one nozzle is deactivated and a second value of the preceding sensor signal when the at least one nozzle is activated.For example, the size threshold (for the information related to the size threshold) can be at least 10% (or at least 20%) higher (or lower) than the first value and at least 10% (or at least 20%) lower (or higher) than the second value.

[0077] For example, the control module can be designed to provide self-monitoring control of the sensor threshold using analog intensity values ​​- for significant differences between the sensor's on / off levels, the threshold can be calculated to be between the on and off levels, which can lead to higher sensor stability.

[0078] The at least one 410 interface can correspond to one or more inputs and / or outputs for receiving and / or transmitting information, which may be in digital (bit) values ​​according to a specified code, within a module, between modules, or between modules of different entities. The at least one 410 interface can have or correspond to an interface for external communication. The at least one 410 interface can have a direct I / O (Input / Output) for equipment interaction (media on / off values, process termination, etc.) and / or external communication for monitoring and process control (e.g., APC, Advanced Process Control).

[0079] In exemplary embodiments, the control module 420 can be implemented using one or more processing units, one or more processing elements, or any means of processing, such as a processor, a computer, or a programmable hardware component capable of operation with appropriately adapted software. In other words, the described function of the control module 420 can also be implemented in software that is then executed on one or more programmable hardware components. Such hardware components can include a general-purpose processor, a digital signal processor (DSP), a microcontroller, etc.

[0080] Further details and aspects of the device 400 are described in connection with the proposed concept or one or more preceding or following (e.g. Fig. Examples mentioned in sections 1 to 3i, 4a-5) are mentioned. Device 400 may have one or more additional optional features corresponding to one or more aspects of the proposed concept or to one or more examples described above or below.

[0081] Fig. Figure 4a shows a block diagram of an embodiment of a device 400a for providing a control signal for a liquid dispensing system. The device 400a can be similar to the one described in connection with Fig. The semiconductor device 400a described in section 4 can be implemented. The device 400a can be configured to obtain information relating to a detected light intensity (e.g., in a sensor signal) from a detection head 402 404 (e.g., from a sensor module 120, as described in conjunction with Fig. (as described in 1-3). The device can further be configured to obtain information relating to the activation of a media value (e.g., activation of a nozzle for liquid dispensing) from a centrifugal etching tool 406 408 (which may have a liquid dispensing system). The device 400a (e.g., a PLC (programmable logic controller) system) can be configured to determine a mismatch between the activation information and the detected light intensity. If the detected light intensity is high and the medium is activated, everything may function correctly and a tool stop may not be necessary. If the detected light intensity is low and the medium is activated, the device 400a can be configured to detect a fault, e.g., due to a media interruption, and can provide a control signal 410 to cause a stop of the centrifugal etching tool.If the detected light intensity is low and the medium is deactivated, everything may function correctly and a tool stop may not be necessary. If the detected light intensity is high and the medium is deactivated, a drop of the medium (e.g., liquid) may be detected, and the device 400a may be configured to provide a control signal 410 to cause a stop of the centrifugal etching tool 406, for example. Furthermore, the device 400a may be configured to provide information regarding the status of the device to an external evaluation module 412, e.g., for monitoring or controlling a chemical plant, e.g., via a tool with Advanced Process Control (APC).

[0082] Further details and aspects of the device 400a are described in connection with the proposed concept or one or more preceding or following (e.g. Fig. Examples described in sections 1 to 4 and 5 are mentioned. Device 400a may have one or more additional optional features corresponding to one or more aspects of the proposed concept or to one or more of the examples described above or below.

[0083] Fig. Figure 5 presents a flowchart of a method 500 for providing a control signal to a liquid dispensing system. The method includes receiving 510 a sensor signal containing information about whether a liquid is being dispensed through a nozzle of the liquid dispensing system. The method further includes detecting 520 a faulty dispensing of liquid through the nozzle based on the sensor signal. The method further includes providing 530 a control signal based on a detected faulty dispensing of liquid through the nozzle.

[0084] For example, detecting a faulty liquid dispensing may involve detecting whether liquid is being dispensed through the nozzle, based on the sensor signal, and determining information related to a mismatch between whether liquid is being dispensed through the nozzle and information related to nozzle activation. Such a mismatch may correspond to a faulty liquid dispensing.

[0085] For example, the method 500 can further include receiving a status signal containing information about the activation of the nozzle of the liquid dispensing system (e.g., from the liquid dispensing system). The detection 520 of a faulty dispensing of liquid through the nozzle can further be based on the information relating to the activation of the nozzle.

[0086] The method can be configured to detect liquid dripping from deactivated nozzles, enabling the detection of defects in a manufacturing process (e.g., wafer fabrication) during production. Early detection of dripping allows for timely intervention to prevent contamination of subsequent processing materials. Furthermore, the sensor signal can be used to monitor liquid flow, for example, to detect positive or negative deviations from a planned quantity (e.g., duration or volume) of liquid to be dispensed.

[0087] Further details and aspects of Procedure 500 are related to the proposed concept or one or more above or below (e.g. Fig.The examples described in sections 1 to 4a) are mentioned. Method 500 may have one or more additional optional features corresponding to one or more aspects of the proposed concept or to one or more of the examples described above or below.

[0088] Centrifugal etching processes can be used, for example, to remove specific physical layers (e.g., an oxide) from a wafer or to remove crystal damage after grinding. Depending on the layer to be removed, different chemical media (e.g., liquids) can be centrifugally ejected from the wafer. Sometimes a combination of chemicals (one after the other) may be necessary to achieve the desired results.

[0089] A media delivery arm (e.g., comprising one or more nozzles of a liquid delivery system) can move across the wafer diameter and deliver medium 1, 2, or 3 (which can be different media / liquids). Typically, only one medium (e.g., liquid) is used at a time. The process might be as follows: The first medium can be shut off after a defined time, and the remaining medium can be ejected from the wafer before the second medium is activated. Occasionally, a drop of medium 1 may occur during the process of medium 2, or even after etching is complete. An unintended release of the medium (e.g., a drop) can frequently cause wafer loss, which may not be detected during the process. In some cases, between 20% and 50% of all lost wafers can be attributed to a drop from the media delivery arm.Considerable effort can be made to prevent the media delivery device from dripping and to detect dripping. Other systems may not significantly reduce wafer loss caused by dripping and may not include a suitable drip detection module. Such a module (e.g., from exemplary embodiments) can detect a drip during the process, providing the opportunity to intervene.

[0090] Exemplary embodiments can provide a drip sensor for centrifugal etching processes. At least some embodiments can be based on the use of a laser light layer combined with a detector for each medium to detect a drip when the medium should be switched off.

[0091] Other systems may not provide reliable technology to prevent the dispensing device from dripping, or they may not provide a module that reliably detects a drip. A drip from the media dispensing device can commonly cause wafer loss and may go undetected during the process. For example, the entire batch or multiple batches (of wafers) may be affected.

[0092] In one embodiment, a liquid dispensing system may have three nozzles for three different chemicals in a media dispensing device. Only one medium may be dispensed at a time. An unintentional drip of another medium could lead to wafer loss. At least some embodiments may be based on liquid detection.

[0093] Exemplary embodiments can utilize three optical light layers (laser curtains, one sensor for each medium). A laser curtain can include a transmitter and a detector. The transmitter can emit laser radiation in the form of a light layer with a width comparable to that of a medium dispensing nozzle. The light can be transmitted under the nozzle to the detector (e.g., a sensor module), which can be configured to convert the light intensity into a computable signal. Whenever something (e.g., a drop of chemical) passes through the light layer (e.g., along a precisely defined optical path), the detector can be configured to deliver the corresponding signal to its output. Exemplary embodiments may not be limited to the use of a specific sensor. For example, any type of optical (or electromagnetic radiation) detector could be used.

[0094] For example, the detection head may be insensitive to misalignment and enable reliable and stable media on / off detection. For example, the liquid dispensing system may be insensitive to mechanical deviations. For example, the medium (liquid) may change color and absorption properties over time. Some embodiments may suppress the influence of changing absorption (behavior) of the medium. For example, at least some embodiments may be based on diffraction, absorption, or refraction. For example, some embodiments may provide self-adjusting media on / off thresholds.

[0095] One of these sensors can be used for each medium; for example, three sensors may be required for three different media. This allows for independent detection of a droplet from each of the three media. The sensor housings can be chemically resistant, for example.

[0096] The sensors are read by a PLC (Programmable Logic Controller). The PLC can record the sensor input signals and the tool signals (indicating whether a medium is currently switched on or off). The PLC software (e.g., an in-house development) can process the input signals and send an error signal to the centrifugal etching tool if necessary. In the event of an error message from the PLC, the centrifugal etching tool can stop the process after the currently processed wafer and display an error message.

[0097] Intervention can be triggered immediately after a single wafer is compromised, dramatically reducing wafer loss. With other systems, an entire batch of wafers or multiple batches can be compromised before a single drop from the media delivery device is detected.

[0098] Further embodiments may provide a computer program with program code for performing one of the above methods when the computer program is executed on a computer or processor. A person skilled in the art would readily recognize that steps of various methods described above can be performed by programmed computers. Some embodiments are intended to include program storage devices, such as digital data storage media, that are machine- or computer-readable and encode machine-executable or computer-executable programs of instructions, wherein the instructions perform some or all of the steps of the methods described above. The program storage devices may be, for example, digital storage devices, magnetic storage media such as magnetic disks and magnetic tapes, hard disk drives, or optically readable digital data storage media.Further embodiments should also cover computers programmed to perform the steps of the procedures described above, or (field) programmable logic arrays ((F)PLA = (Field) Programmable Logic Arrays) or (field) programmable gate arrays ((F)PGA = (Field) Programmable Gate Arrays) programmed to perform the steps of the procedures described above.

[0099] The description and drawings represent only the principles of the disclosure. It is therefore understood that the person skilled in the art may derive various arrangements which, although not expressly described or shown here, embody the principles of the disclosure and are contained within its meaning and scope. Furthermore, all examples given here are expressly intended for teaching purposes only, to assist the reader in understanding the principles of the disclosure and the concepts contributed by the inventor(s) to the advancement of the technology, and are to be understood as serving without limitation to such specifically listed examples and conditions. Furthermore, all statements made herein concerning principles, aspects, and embodiments of the disclosure, as well as specific examples thereof, are intended to encompass their equivalents.

[0100] The person skilled in the art should understand that all block diagrams herein represent conceptual views of exemplary circuits embodying the principles of the disclosure. Similarly, it is understood that all flowcharts, process diagrams, state transition diagrams, pseudocode, and the like represent various processes that are essentially represented in a computer-readable medium and can thus be executed by a computer or processor, irrespective of whether such a computer or processor is explicitly depicted.

[0101] Furthermore, the following claims are hereby included in the detailed description, where each claim can stand alone as a separate embodiment. While each claim can stand alone as a separate example, it should be noted that—although a dependent claim may refer in the claims to a specific combination with one or more other claims—other embodiments may also include a combination of the dependent claim with the subject matter of any other dependent or independent claim. These combinations are suggested here unless it is stated that a particular combination is not intended. Furthermore, features of a claim are also intended to be included for any other independent claim, even if that claim is not directly dependent on the independent claim.

[0102] It should also be noted that methods disclosed in the description or in the claims may be implemented by a component with means for carrying out each of the respective steps of these methods.

[0103] Furthermore, it is understood that the disclosure of several steps or functions in the description or the claims should not be interpreted as being in a specific order. The disclosure of several steps or functions therefore does not restrict them to a specific order, unless these steps or functions are not interchangeable for technical reasons. Furthermore, in some embodiments, a single step may include or be subdivided into several sub-steps. Such sub-steps may be included and form part of the disclosure of that single step, unless they are expressly excluded.

Claims

[1] A liquid delivery system (100, 200, 300) comprising: at least one nozzle (110) configured to dispense a liquid; at least one sensor module (120) configured to provide a sensor signal comprising information relating to whether liquid is dispensed through the at least one nozzle (110); and at least one electromagnetic emitter module (122) configured to emit electromagnetic radiation in the direction of a path of falling liquid discharged through the at least one nozzle (110), wherein at least a part of the at least one sensor module (120) is arranged near the nozzle (110), wherein the at least one sensor module (120) is designed to provide the sensor signal based on an influence of the dispensed liquid on the electromagnetic radiation, wherein the at least one sensor module (120) is designed to determine the sensor signal based on a refraction of the emitted electromagnetic radiation caused by the dispensed liquid, wherein a portion of the electromagnetic radiation emitted by the at least one electromagnetic emitter module (122) and received by the at least one sensor module (120) while liquid is being dispensed through the at least one nozzle (110) is at least 10% higher than a portion of the electromagnetic radiation emitted by the at least one electromagnetic emitter module (122) and received by the at least one sensor module (120) while no liquid is being dispensed through the at least one nozzle (110). [2] A liquid delivery system (100, 200, 300) comprising: at least one nozzle (110) configured to dispense a liquid; at least one sensor module (120) configured to provide a sensor signal comprising information relating to whether liquid is dispensed through the at least one nozzle (110); at least one electromagnetic emitter module (122) configured to emit electromagnetic radiation in the direction of a path of falling liquid discharged through the at least one nozzle (110), wherein at least a part of the at least one sensor module (120) is arranged near the nozzle (110), wherein the at least one sensor module (120) is designed to provide the sensor signal based on an influence of the dispensed liquid on the electromagnetic radiation, wherein a portion of the electromagnetic radiation emitted by the at least one electromagnetic emitter module (122) and received by the at least one sensor module (120) while liquid is being dispensed through the at least one nozzle (110) is at least 10% higher than a portion of the electromagnetic radiation emitted by the at least one electromagnetic emitter module (122) and received by the at least one sensor module (120) while no liquid is being dispensed through the at least one nozzle (110), wherein the electromagnetic emitter module (122) is configured to emit electromagnetic radiation in the direction of at least a part of the at least one sensor module (120). [3] The liquid dispensing system according to any one of the preceding claims, wherein the at least one sensor module (120) comprises an optical sensor configured to generate the sensor signal based on light received after interaction with the liquid dispensed through the at least one nozzle (110). [4] The liquid dispensing system according to any one of the preceding claims, further comprising an opening (130) configured to shield the at least one sensor module (120) from a portion of the electromagnetic radiation emitted by the at least one electromagnetic emitter module (122). [5] The liquid dispensing system according to claim 4, wherein a lateral distance between the at least one opening (130) and the dispensed liquid is less than 2 cm. [6] The liquid dispensing system according to any one of claims 4 or 5, wherein the opening (130) has a minimum width of less than 10 mm and more than 0.4 mm. [7] The liquid dispensing system according to any one of the preceding claims, wherein the at least one electromagnetic emitter module (122) is configured to emit light having a wavelength between 100nm and 100µm. [8] The liquid dispensing system according to any one of the preceding claims, wherein the at least one electromagnetic emitter module (122) is configured to emit electromagnetic radiation at a wavelength at which more than 30% of a portion of the electromagnetic radiation striking the liquid dispensed through the at least one nozzle (110) passes through the liquid dispensed through the at least one nozzle (110). [9] The liquid dispensing system according to one of claims 1 or 2, further comprising at least one acoustic emitter module configured to emit ultrasound at a frequency between 20 kHz and 5 GHz, wherein the at least one sensor module (120) is configured to generate the sensor signal based on an influence of the dispensed liquid on the ultrasound. [10] The liquid dispensing system according to one of claims 1 or 2, wherein the at least one sensor module (120) is configured to induce eddy currents in the liquid dispensed through the at least one nozzle (110), and wherein the at least one sensor module (120) is configured to generate the sensor signal based on an intensity of eddy currents induced in the dispensed liquid. [11] The liquid dispensing system according to any one of the preceding claims, wherein a lateral distance between the at least one sensor module (120) and the liquid dispensed through the at least one nozzle (110) is less than 5 cm. [12] The liquid dispensing system according to any one of the preceding claims, further comprising a housing (140) for the at least one sensor module (120), wherein the housing (140) is chemically resistant to at least one of sulfuric acid, nitric acid and hydrofluoric acid. [13] The liquid dispensing system according to claim 12, wherein at least a part of the housing (140) disposed between at least one of an electromagnetic emitter module (122) or the sensor module (120) and a path of falling of the dispensed liquid may comprise a semi-transparent material. [14] System comprising: a liquid dispensing system (100, 200, 300) according to any one of the preceding claims; and a device (400) for providing a control signal for the liquid dispensing system (100, 200, 300), comprising: at least one interface (410) configured to receive the sensor signal; and a control module (420) configured to detect an erroneous dispensing of liquid through the nozzle (110) based on the sensor signal, wherein the at least one interface (410) is configured to provide a control signal based on a detected, faulty dispensing of liquid through the nozzle (110). [15] The system of claim 14, wherein the sensor signal comprises information related to electromagnetic radiation measured by the at least one sensor module (120), wherein the control module (420) is configured to compare a radiation intensity level of the electromagnetic radiation measured by the at least one sensor module (120) with an intensity threshold to detect whether liquid is erroneously dispensed through the nozzle (110). [16] The system of claim 14 or 15, wherein the control module (420) is configured to provide the control signal to trigger at least one of a warning or a stop of the liquid dispensing system (100, 200, 300) when the sensor signal indicates that liquid is being dispensed, and information related to activation of the nozzle (110) indicates that the nozzle (110) is deactivated. [17] The system of any one of claims 14-16, wherein the control module (420) is configured to determine an amount of liquid dispensed through the nozzle (110) based on the sensor signal, wherein the control module (420) is configured to provide the control signal to trigger at least one of a warning or a stop of the liquid dispensing system (100, 200, 300) when information related to activation of the nozzle (110) indicates that the nozzle (110) is activated and the amount of liquid dispensed is below a size threshold. [18] A method (500) for providing a control signal for a liquid dispensing system (100, 200, 300) according to any one of claims 1 to 13, comprising: Receiving (510) the sensor signal; Detecting (520) a faulty dispensing of liquid through the nozzle (110) based on the sensor signal; and Providing (530) a control signal based on a detected, faulty dispensing of liquid through the nozzle (110).

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