Nozzle monitoring system, deposition apparatus and method of detecting clogging of one or more nozzles

Abstract

A nozzle monitoring system (100) for monitoring one or more nozzles (210) of a deposition source (200) is described. The nozzle monitoring system (100) includes a substrate support (110) configured to hold a substrate (10), and a camera (120) configured to monitor a material accumulation at a nozzle opening (211) of the one or more nozzles (210). The camera (120) is arranged behind a front side (111) of the substrate support. Further, a deposition apparatus for deposition of a material on a substrate and a method of detecting clogging of one or more nozzles are described.

Description

NOZZLE MONITORING SYSTEM, DEPOSITION APPARATUS AND METHOD OF DETECTING CLOGGING OF ONE OR MORE NOZZLESTECHNICAL FIELD

[0001] Embodiments of the present disclosure relate to systems for monitoring one or more nozzles of a deposition source. Further embodiments of the present disclosure relate to deposition apparatuses for material deposition on substrates. Yet further embodiments relate to methods of detecting clogging of one or more nozzles.BACKGROUND

[0002] An organic light-emitting diode (OLED) is a light-emitting diode in which an electroluminescent layer is a film of organic compounds that emits light in response to an electric current. Since OLEDs emit light directly without involving backlight and color filters, the color gamut and viewing angles possible with OLED displays are greater as compared to traditional LCD displays. Further, OLEDs can be manufactured on flexible substrates, and accordingly, they can be utilized in a variety of applications. OLEDs are used in the manufacture of television screens, computer monitors, mobile phones, other hand-held devices, etc., for displaying information. OLEDs can also be used for general space illumination. An OLED display, for example, may include layers of organic material situated between two electrodes that are deposited on a substrate in a manner to form a matrix display panel having individually energizable pixels.

[0003] Organic materials and metallic materials are deposited on a substrate in a vacuum processing chamber for OLED manufacturing. Metallic materials are employed as, for example, electrode materials or electron transport layer (ETL) materials. The materials to be deposited are evaporated with evaporation sources, and the evaporated materials are directed on a substrate by nozzles. Metallic materials are, for example, typically evaporated in an evaporation source at atemperature of 1 ,000°C or above, or 1 ,500°C or above. Organic materials are typically evaporated in an evaporation source arrangement at temperatures between 250°C and 450°C.

[0004] Metallic and organic evaporators can be used for the production of organic light-emitting diodes (OLED). Also other applications utilize evaporators for depositing metal or organic layers, for example, on large area substrates. An OLED display, for example, may include a plurality of layers of organic material situated between two electrodes that are deposited on a substrate. One of the electrodes can include a transparent conductive layer such as indium tin oxide (ITO) or other transparent conductive oxide materials (TOO). The second electrode can include a metal or a metal alloy.

[0005] Evaporators bear the potential risk of nozzle clogging. Nozzle clogging refers to the obstruction or blockage of the nozzle, which is the final passage through which a material to be deposited flows before being deposited on a substrate. The nozzle is used to precisely control the flow of material onto the substrate surface.

[0006] When nozzle clogging occurs, some form of debris or residue has accumulated within the nozzle, hindering or completely obstructing the flow of the intended substance. This obstruction disrupts the smooth operation of the system in the manufacturing processes, such as in the production of coatings, nozzle clogging can have serious consequences. It can result in interruptions to production, leading to downtime and potentially significant financial losses. Moreover, if the clogging is not promptly addressed, it can adversely affect the quality and consistency of the final product.

[0007] Accordingly, there is a demand for nozzle monitoring systems, deposition apparatuses and methods of detecting clogging of nozzles, which at least partially overcome one or more of the disadvantages of the state of the art.SUMMARY

[0008] In light of the above, a nozzle monitoring system for monitoring one or more nozzles of a deposition source, a deposition apparatus for deposition of a material on a substrate, and a method of detecting clogging of one or more nozzles according to the independent claims are provided. Further aspects, benefits, and features of the present disclosure are apparent from the claims, the description, and the accompanying drawings.

[0009] According to an aspect of the present disclosure, a nozzle monitoring system for monitoring one or more nozzles of a deposition source is provided. The nozzle monitoring system includes a substrate support configured to hold a substrate. Additionally, the nozzle monitoring system includes a camera configured to monitor a material accumulation at a nozzle opening of the one or more nozzles. The camera is arranged behind a front side of the substrate support.

[0010] According to another aspect of the present disclosure, a deposition apparatus for deposition of a material on a substrate is provided. The deposition apparatus includes a vacuum chamber. Additionally, the deposition apparatus includes one or more deposition sources in the vacuum chamber. Further, the deposition apparatus includes a nozzle monitoring system according to any embodiments of the present disclosure, the nozzle monitoring system being arranged inside the vacuum chamber.

[0011] According to a further aspect of the present disclosure, a method of detecting clogging of one or more nozzles is provided. The method includes monitoring a material accumulation at a nozzle opening of the one or more nozzles by using a nozzle monitoring system having a camera being arranged behind a front side of a substrate support configured to hold a substrate. Additionally, the method includes analyzing image data recorded by the camera by a data analysis unit to obtain status information with respect to an open cross-sectional area of the nozzle opening. Further, the method includes categorizing the status information on the open cross-sectional area into various clogging statuses of nozzle opening.

[0012] Embodiments are also directed at apparatuses for carrying out the disclosed methods and include apparatus parts for performing each described method aspect. These method aspects may be performed by way of hardware components, a computer programmed by appropriate software, by any combination of the two or in any other manner. Furthermore, embodiments according to the disclosure are also directed at methods for operating the described apparatus. The methods for operating the described apparatus include method aspects for carrying out every function of the apparatus.BRIEF DESCRIPTION OF THE DRAWINGS

[0013] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments. The accompanying drawings relate to embodiments of the disclosure and are described in the following:FIG. 1 shows a schematic top view of a nozzle monitoring system according to embodiments of the present disclosure;FIG. 2A shows a schematic top view of a nozzle monitoring system according to further embodiments of the present disclosure;FIG. 2B shows a schematic front view of a nozzle monitoring system according to embodiments of the present disclosure;FIG. 2C shows a schematic front view of a nozzle monitoring system according to a particular example of the present disclosure;FIG. 3 shows a schematic top view illustrating further embodiments of the nozzle monitoring system according to the present disclosure;FIG. 4 shows a schematic front view illustrating further embodiments of the nozzle monitoring system according to the present disclosure;FIG. 5 shows a schematic top view illustrating further embodiments of the nozzle monitoring system according to the present disclosure;FIG. 6 shows a schematic side view illustrating further embodiments of the nozzle monitoring system according to the present disclosure;FIG. 7 shows a schematic side view of a deposition apparatus according to embodiments of the present disclosure; andFIG. 8 shows a block diagram for illustrating a method of detecting clogging of one or more nozzles according to embodiments of the present disclosure.DETAILED DESCRIPTION OF EMBODIMENTS

[0014] Reference will now be made in detail to the various embodiments, one or more examples of which are illustrated in each figure. Each example is provided by way of explanation and is not meant as a limitation. For example, features illustrated or described as part of one embodiment can be used on or in conjunction with any other embodiment to yield yet a further embodiment. It is intended that the present disclosure includes such modifications and variations.

[0015] Within the following description of the drawings, the same reference numbers refer to the same or to similar components. Generally, only the differences with respect to the individual embodiments are described. Unless specified otherwise, the description of a part or aspect in one embodiment can apply to a corresponding part or aspect in another embodiment as well.

[0016] With exemplary reference to FIG. 1 , a nozzle monitoring system 100 for monitoring one or more nozzles 210 of a deposition source 200 according to embodiments of the present disclosure is described. According to embodiments, which can be combined with other embodiments described herein, the nozzle monitoring system 100 includes a substrate support 110 configured to hold a substrate 10. Additionally, the nozzle monitoring system 100 includes a camera 120 configured to monitor a material accumulation at a nozzle opening 211 of theone or more nozzles 210. The camera 120 is arranged behind a front side 111 of the substrate support 110.

[0017] Accordingly, compared to the state of the art, an improved nozzle monitoring system is provided. In particular, the nozzle monitoring system according to embodiments described herein is beneficially configured for monitoring nozzles from the front, such that clogging can be observed with high accuracy. Another advantage is that nozzle clogging can be observed in real time.

[0018] Before various further embodiments of the present disclosure are described in more detail, some aspects with respect to some terms used herein are explained.

[0019] In the present disclosure, a “nozzle monitoring system” can be understood as a system of components or devices which are configured to monitor one or more nozzles of a deposition source, particularly a material accumulation at one or more nozzle openings.

[0020] In the present disclosure, a “substrate support” can be understood as a structure that provides a stable base or foundation for a substrate to be placed upon or attached to. In other words, the substrate support can be configured to provide a fixture or platform for securely supporting a substrate during substrate processing, e.g. coating. Typically, the substrate 10 is provided on a front side 111 of the substrate support 110, as exemplarily indicated in FIG. 3. Accordingly, typically a backside 10B of the substrate 10 is at least partially in contact with the front side 111 of the substrate support 110. The front side 10F of the substrate 10 typically faces the deposition source. Typically, the substrate support ensures stability and proper positioning of the substrate during processing, e.g. layer deposition. It is to be understood that the substrate support can be configured for holding a large area substrate as described herein. The substrate support may also be referred to as a substrate holder or substrate carrier. A substrate holder typically refers to a static substrate support, i.e. a substrate support which is notmoving during substrate processing. In other words, a substrate holder does not travel within a processing system, particularly during substrate processing.

[0021] A substrate carrier typically refers to a dynamic substrate support, i.e. a substrate support which is moved during substrate processing, e.g. past one or more deposition sources for depositing a layer on a substrate supported by the carrier. In particular, the substrate support can be a substrate carrier for moving the substrate past one or more deposition sources for providing a coating, e.g. of evaporated material, on the substrate.

[0022] According to embodiments, which can be combined with other embodiments described herein, the substrate support can include an electrostatic chuck (E-chuck) providing an electrostatic force for holding the substrate, particularly at a substrate support surface of the substrate support, e.g. the front side of the substrate support. For example, the substrate support may include an electrode arrangement configured to provide an attracting force acting on the substrate. Typically, the substrate support is configured for holding the substrate 10 during material deposition in a substantially vertical orientation. A “substantially vertical orientation” of the substrate can be understood in that the orientation of the substrate is vertical within a tolerance T of T < ±15°, particularly T < ±10°, more particularly T < ±5°, from the perfect vertical orientation. Alternatively, the holder can be configured holding a substrate during material deposition in a substantially horizontal orientation. A “substantially horizontal orientation” of the substrate or the mask can be understood in that the orientation of the substrate or the mask is horizontal within a tolerance T of T < ±15°, particularly T < ±10°, more particularly T < ±5°, from the perfect horizontal orientation.

[0023] Embodiments described herein particularly relate to deposition of materials, e.g. for display manufacturing on large area substrates. According to some embodiments, large area substrates or substrate supports supporting one or more substrates may have a size of 0.5 m2or larger, particularly of 1 m2or larger. For instance, the deposition system may be adapted for processing large area substrates, such as substrates of GEN 4.5, which corresponds to about 0.67 m2ofsubstrate (0.73x0.92m), GEN 5, which corresponds to about 1.4 m2 substrates (1.1 m x 1 .3 m), GEN 6, which corresponds to about 2.7 m2 (1 .5 m x about 1.8 m), GEN 7.5, which corresponds to about 4.29 m2 substrates (1.95 m x 2.2 m), GEN 8.5, which corresponds to about 5.7 m2 substrates (2.2 m x 2.5 m), or even GEN 10, which corresponds to about 8.7 m2 substrates (2.85 m x 3.05 m). Even larger generations such as GEN 11 and GEN 12 and corresponding substrate areas can similarly be implemented. According to yet further implementations, half sizes of the above-mentioned substrate generations can be processed.

[0024] In the present disclosure, a “substrate” can be understood as a material or object onto which some form of processing, treatment, or material deposition is applied. In particular, the substrate can be a large area substrate as described herein. Typically, the substrate is of transparent material, e.g. transparent glass or transparent plastic.

[0025] According to embodiments, which can be combined with other embodiments described herein, the substrate thickness can be from 0.1 to 1 .8 mm. For example, the substrate thickness can be about 0.9 mm or below, such as 0.5 mm. The term “substrate” as used herein may particularly embrace substantially inflexible substrates, e.g., a glass plate, a plastic plate or other suitable substrates. However, the present disclosure is not limited thereto and the term “substrate” may also embrace flexible substrates such as a web or a foil. The term “substantially inflexible” is understood to distinguish over “flexible”. Specifically, a substantially inflexible substrate can have a certain degree of flexibility, e.g. a glass plate having a thickness of 0.9 mm or below, such as 0.5 mm or below, wherein the flexibility of the substantially inflexible substrate is small in comparison to the flexible substrates. In particular, the substrate can be a “large area substrate” as described herein.

[0026] In the present disclosure, a “camera" can be understood as a device used to capture and record visual images, typically through the use of optics and sensors. According to embodiments, which can be combined with other embodiments described herein, the camera is a high-resolution camera. A high-resolution camera is a device capable of capturing images with a high level of detail and clarity. Resolution refers to the amount of detail that a camera sensor can capture, typically measured in pixels. A higher resolution means that the camera can record finer details in an image, resulting in sharper and more detailed pictures. High-resolution cameras typically feature larger sensors, which can capture more light and detail compared to smaller sensors. Larger sensors are particularly advantageous in low-light conditions and for achieving shallow depth of field effects.

[0027] Alternatively, the camera can be an infrared camera. An infrared camera, also referred to as thermal camera or thermographic camera, is a device that detects infrared radiation (heat) emitted by objects and converts it into a visible image. Unlike conventional cameras, which capture visible light, infrared cameras operate in the infrared spectrum and can produce images based on temperature differences.

[0028] With exemplary reference to FIG. 2A, according to embodiments, which can be combined with other embodiments described herein, the substrate support 110 has a reception 113. The camera 120 is at least partially arranged in the reception 113.

[0029] In the present disclosure, a “reception" of the substrate support can be understood as a designated area or space within the substrate support that is specifically configured to accommodate the camera. The expression “the camera is at least partially arranged in the reception” can be understood in that the camera may not necessarily fill the entire space of the reception, and that there can be some room or space within the reception that is not occupied by the camera. Further, the expression “the camera is at least partially arranged in the reception” can be understood in that the camera is arranged within the reception and may extend partially beyond the boundaries of the reception. It is to be understood that in embodiments in which the camera is connected to a drive to move the camera along at least one linear trajectory, the reception is typically configured to allow the movement of the camera along said linear trajectory.

[0030] According to embodiments, which can be combined with other embodiments described herein, a front side 114 of the reception 113 is covered by the substrate 10, as exemplarily indicated in FIG. 3. Accordingly, it is to be understood that a field of view 121 of the camera 120 is directed towards the backside 10B of the substrate 10. More specifically, typically the optics 122 of the camera 120 are directed towards the backside 10B of the substrate 10. Accordingly, and beneficially, nozzle monitoring can be carried out from the backside of the substrate, such that the nozzle front, particularly the nozzle opening, can be observed while the optics of the camera are protected from deposition material. The camera 120 may be inserted into the reception 13 from a backside 115 of the reception 113.

[0031] Typically, at least the portion of the substrate 10 covering the front side 114 of the reception 113 is transparent. In the present disclosure the term “transparent” can be understood as referring to the optical property of a material, particularly the substrate, to allow light to pass through with minimal distortion, enabling objects on the other side to be seen. In other words, a material is considered transparent if the material allows light to pass through the material without significant absorption, scattering, or reflection. Transparency can be quantified by the material's transmittance (TM), which measures the percentage of incident light that passes through the material. A higher transmittance indicates greater transparency. According to embodiments, which can be combined with other embodiments described herein, at least the portion of the substrate 10 covering the front side 114 of the reception 113 has a transmittance TM > 50%, particularly TM > 70%, more particularly TM > 80%, e.g. TM > 90%.

[0032] With exemplary reference to FIG. 2B, according to embodiments, which can be combined with other embodiments described herein, a protection glass 123 can be arranged in front of the camera 120, particularly in front of the optics 122 of the camera 120. Further, a movable protection cover 124 may be provided, which is configured to be moved in front of the protection glass 123. Accordingly, the protection cover 124 can be moved in front of the protection glass 123 forprotecting the protection glass 123 from material deposition. Further, it is to be understood that the protection cover 124 can be moved out of the field of view of the camera, such that the camera can monitor a material accumulation at a nozzle opening of the one or more nozzles as described herein. The protection cover 124 may also be referred to as protection shield. The arrow 128 in FIG. 2B indicates a possible movement of the protection cover 124.

[0033] With exemplary reference to FIG. 3, according to embodiments, which can be combined with other embodiments described herein, the reception 113 for the camera is arranged in an edge region 118 of the substrate support 110. In particular, the edge region 118 can be an edge exclusion region. An “edge exclusion region” can be understood as a region at the edge of the substrate which is subjected to less or no exposure to evaporated material by the provision of a shield or an edge exclusion mask, arranged in front of the substrate. The edge region 118 may have a width W selected from a range between a lower limit Wi and an upper limit W2, i.e. W1 < W< W2. The lower limit W1 can be W1 = 5 mm, particularly W1 = 10 mm, more particularly W1 = 15 mm. The upper limit W2 can be W2 = 20 mm, particularly W2 = 25 mm, more particularly W2 = 30 mm.

[0034] FIG. 3 shows an exemplary configuration in which an edge exclusion device 20 (e.g. shield, particularly a movable shield, or a mask, particularly an edge exclusion mask) is arranged in front of the substrate. The portion of the substrate, particularly the edge of the substrate, which is covered by the edge exclusion device 20 may be referred to as overlap region 119. Typically, the overlap region 119 is smaller than the edge region 118.

[0035] FIG. 3 illustrates the deposition source 200 with the one or more nozzles 210 at three different relative positions (T1 , T2, T3) with respect to the camera 120. The three different relative positions (T1, T2, T3) typically correspond to three different relative positions in time, when either the deposition source 200 is moving relative to the substrate support 110 or the substrate support 110 is moving relative to the deposition source. In other words, the substrate support 110 may be static while the deposition source 200 moves past the substrate 10, e.g. in a lateraldirection (e.g. the y-direction in FIG 3), or the deposition source 200 may be static while the substrate support 110, with the substrate 10, moves laterally past the deposition source 200. From FIG. 3 it is to be understood that the nozzle opening(s) 211 of the one or more nozzles 210 of the deposition source 200 enter and leave the field of view 121 of the camera 120 over time, such that the camera can capture images of the nozzle opening(s) 211 from the front.

[0036] According to embodiments, which can be combined with other embodiments described herein, the camera 120 is arranged inside an atmospheric box 130, as exemplarily shown in FIG. 5. In the present disclosure, an “atmospheric box” can be understood as an enclosed volume or space in which atmospheric conditions, particularly atmospheric pressure conditions, are provided and / or can be controlled. Typically, the atmospheric box 130 has a transparent front 131 or window. The transparent front 131 allows the camera to capture and record visual images of the nozzle opening(s) 211 of the one or more nozzles 210. The atmospheric box 130 can at least partially be arranged in the reception 113. The atmospheric box 130 may be attached or connected to the substrate support 110.

[0037] According to embodiments, which can be combined with other embodiments described herein, the nozzle monitoring system 100 includes a communication module 140 configured to send image data recorded by the camera 120 to a data analysis unit 150. Accordingly, it is to be understood that the communication module 140 is typically configured to receive image data from the camera 120. The communication module may be a separate module. Alternatively, the communication module may be part of the camera. Accordingly the camera may be provided with an integrated communication module. FIG.5 shows an exemplary configuration, in which a separate communication module 140 is provided.

[0038] The data analysis unit 150 can be understood as a component configured to receive and process the data transmitted by the communication module 140. In particular, the data analysis unit 150 is configured to analyze thereceived image data with respect to an open cross-sectional area of a nozzle opening, as described herein. The image analysis may involve image processing, pattern recognition, defect detection, or any other form of analysis relevant to the monitoring and maintenance of the nozzles. The data analysis unit 150 may incorporate algorithms, machine learning models, or other analytical tools to interpret the image data and extract meaningful insights or actionable information.

[0039] According to embodiments, which can be combined with other embodiments described herein, the communication module 140 is provided within an atmospheric box. In particular, the communication module 140 can be provided within a further atmospheric box 131 , as exemplarily shown in FIG. 5. Typically, the further atmospheric box 131 in which the communication module 140 is arranged is a different atmospheric box than the atmospheric box 130 in which the camera 120 is arranged.

[0040] According to embodiments, which can be combined with other embodiments described herein, the communication module 140 is attached to a frame 116 of the substrate support 110, as exemplarily shown in FIG. 5. In particular, the frame 116 may include a reception 117 for the communication module 140. Accordingly, the communication module 140 can at least partially be arranged in the reception 117 of the frame 116.

[0041] According to embodiments, which can be combined with other embodiments described herein, the communication module 140 includes at least one element selected from the group of a controller 141 , a power supply 142, particularly a battery, and an antenna 143. Typically, the power supply 142 is connected with the controller 141 . The controller can be connected to the camera 120. The line connecting the controller 141 with the camera 120 can include a data transmission line and / or a power supply line for supplying power to the camera 120. Typically, the antenna 143 is connected with the controller 141. The line connecting the controller 141 with the antenna 143 can include a data transmission line and / or a power supply line for supplying power to the antenna 143. It is to beunderstood that data transmission may be conducted via a wired connection or via wireless data transmission technologies.

[0042] According to embodiments, which can be combined with other embodiments described herein, the camera 120 is connected to a drive 125, as schematically indicated in FIG. 3. The drive 125 is configured to move the camera along at least one linear trajectory, for instance along a first linear trajectory x and / or a second linear trajectory y. In FIG. 4 arrow 126 indicates a movement of the camera 120 along an x-direction, particularly the x direction being vertical. Arrow 127 in FIG. 4 indicates a movement of the camera 120 along a y-direction, particularly the y direction being horizontal. As exemplarily indicated in FIG. 4, the reception 113 can be configured to allow a movement of the camera 120 within the reception 130 along the first linear trajectory x and / or the second linear trajectory y. For instance, the reception 130 can have an elongated shape extending substantially over the complete height H of the substrate support 110. Accordingly, and beneficially, the camera can be moved (in FIG. 4 along the x-direction, typically being a vertical direction) such that a plurality of nozzles can be inspected with one camera.

[0043] Further, FIG. 4 shows an exemplary configuration of the substrate 10 having a panel 10P which can be opaque, e.g. since the panel may include a metal pattern. From FIG. 4 it is to be understood that in the case a substrate with an opaque panel is employed, the reception 113 is located at a location of the substrate support 110 which is not covered by said panel 10P.

[0044] With exemplary reference to FIG. 6, according to embodiments, which can be combined with other embodiments described herein, the nozzle monitoring system 100 includes an illumination system 160. Typically, the illumination system 160 includes a light source 161 and an optical fiber 162 for guiding light originating from the light source 161 towards the one or more nozzles 210 to be monitored. The light source 161 can be a white plasma based light source or a LED, particularly a white LED. In particular, the optical fiber 162 can have one or more openings 163 for directing light to the one or more nozzles to be monitored. Thelight 164 from the one or more openings 163 to the one or more nozzles 210 is exemplarily indicted by the doted arrows in FIG. 6. Accordingly, and beneficially, the light originating from a single light source can be passed through the optical fiber with suitable openings at a respective nozzle position to illuminate the plurality of nozzles from the front.

[0045] With exemplary reference to FIG. 6, according to embodiments, which can be combined with other embodiments described herein, the camera 120 can be connected or attached to a frame 170, particularly a movable frame. The frame 170 can be movable in the x-direction and / or the y-direction and / or the z- direction.

[0046] According to embodiments, which can be combined with other embodiments described herein, two or more cameras 120 as described herein can be provided. Features and aspects as described herein with respect to the camera 120 may apply to the two or more cameras. In particular, the nozzle monitoring system may include an array of multiple cameras. Accordingly, it is to be understood that the array of multiple cameras can be configured to monitor material accumulation at nozzle openings of an array of nozzles.

[0047] With exemplary reference to FIG. 7, a deposition apparatus 250 for deposition of a material on a substrate 10 according to embodiments of the present disclosure is described. The deposition apparatus 250 includes a vacuum chamber 251 and one or more deposition sources 200 arranged inside the vacuum chamber 251 . Further, the deposition apparatus 250 includes a nozzle monitoring system 100 according to any embodiments described herein. The nozzle monitoring system 100 is arranged inside the vacuum chamber 251. The deposition apparatus 250 may also be referred to as a vacuum deposition apparatus. The vacuum deposition apparatus can be understood as an apparatus or configured for vacuum deposition of organic or inorganic materials including metallic materials, particularly for display manufacturing, e.g. for OLED display manufacturing.

[0048] In the present disclosure, a "vacuum deposition chamber" can be understood as a chamber configured for vacuum deposition. The term "vacuum", as used herein, can be understood in the sense of a technical vacuum having a vacuum pressure of less than, for example, 10 mbar. Typically, the pressure in a vacuum chamber as described herein may be between 10’5mbar and about 10’8mbar, particularly between 10’5mbar and 10’7mbar.

[0049] In the present disclosure, a “deposition source” can be understood as an arrangement or an assembly configured for material deposition on a substrate as described herein. In other words, the deposition source is configured for providing a source of material to be deposited on the substrate.

[0050] According to embodiments, which can be combined with other embodiments described herein, the one or more deposition sources 200 are evaporation sources. Accordingly, the deposition source 200 may include one or more evaporation crucibles 220 for evaporating material to be deposited. An "evaporation crucible" can be understood as a device having a reservoir for the material to be evaporated by heating the crucible. Accordingly, an "evaporation crucible" can be understood as a source material reservoir, which can be heated to evaporate the source material into a gas by at least one of evaporation and sublimation of the source material. The evaporation crucible can include a heater to evaporate the source material in the crucible into a gaseous source material. For instance, initially the material to be evaporated can be in the form of a powder or a grain. The reservoir can have an inner volume for receiving the source material to be evaporated, e.g. organic or inorganic materials, e.g. metallic materials.

[0051] Further, the deposition source 200 may include one or more distribution assemblies 230 or distribution pipes configured for providing the evaporated material towards the substrate. Typically, the one or more distribution assemblies 230 are connected to the one or more evaporation crucibles 220. The distribution assembly 230 can include a plurality of nozzles 210. The plurality of nozzles 210 may be arranged along a line, particularly in a substantially vertical direction. In FIG. 7 the vertical direction corresponds to the x-direction.

[0052] Accordingly, a distribution assembly as described herein may provide a line source with a plurality of openings and / or nozzles which are arranged in lines along the length of the distribution tube. Accordingly, the distribution assembly can include a linear distribution showerhead, for example, having a plurality of openings, particularly nozzles disposed therein. A showerhead as understood herein can have an enclosure, hollow space, or tube, in which the evaporated material can be provided or guided, for example from the evaporation crucible to the substrate. According to embodiments which can be combined with any other embodiments described herein, the length of the distribution assembly, particularly the distribution pipe, may correspond to at least the height of the substrate to be deposited. In particular, the length of the distribution pipe may be longer than the height of the substrate to be deposited, at least by 10% or even 20%. Accordingly, a uniform deposition at the upper end of the substrate and / or the lower end of the substrate can be provided.

[0053] According to embodiments, which can be combined with other embodiments described herein, the deposition apparatus 200 further includes a transport system 260 for transporting the substrate 10 to be coated past the one or more deposition sources 200. Additionally or alternatively, the deposition apparatus 200 may include a further transport system 270 for moving the one or more deposition sources 200 past the substrate to be coated.

[0054] According to embodiments which can be combined with any other embodiments described herein, the deposition apparatus 250 is configured for material deposition in a substantially vertical orientation of the substrate. Accordingly, typically the vacuum deposition chamber 251 and the deposition source 200 are configured for material deposition on a substantially vertically arranged substrate 10. Accordingly, it is to be understood that the substrate support 110 holding the substrate 10 is typically also configured for holding the substrate in a substantially vertical orientation.

[0055] With exemplary reference to the block diagram shown in FIG. 8, a method 300 of detecting clogging of one or more nozzles according toembodiments of the present disclosure is described. According to embodiments, which can be combined with other embodiments described herein, the method 300 includes monitoring (represented by block 310 in FIG. 8) a material accumulation at a nozzle opening 211 of the one or more nozzles 210 by using a nozzle monitoring system 100 having a camera 120 being arranged behind a front side 111 of a substrate support 110 configured to hold a substrate 10. In particular, the camera 120 can be at least partially arranged in a reception 113 of the substrate support 110. Additionally, the method 300 includes analyzing (represented by block 320 in FIG. 8) image data recorded by the camera 120 by a data analysis unit 150 to obtain status information with respect to an open cross-sectional area of the nozzle opening 211. Further, the method 300 includes categorizing (represented by block 330 in FIG. 8) the status information on the open cross- sectional area into various clogging statuses of nozzle opening 211 . For instance, the clogging statuses can be “open”, “partially clogged” or “fully clogged”.

[0056] According to embodiments, which can be combined with other embodiments described herein, analyzing the image data of the camera 120 by the data analysis unit 150 includes using a machine learning (ML) model. In other words, the data analysis unit 150 can be configured to employ a ML model to analyze the image data recorded by the camera 120. The ML model may be trained using a number of training images of nozzle openings with different open cross- sectional areas. The different open cross-sectional areas can be assigned to different degrees of clogging or different clogging statuses of the nozzle.

[0057] According to embodiments, which can be combined with other embodiments described herein, the method further includes activating (represented by block 340 in FIG. 8) a cleaning mechanism to remove material accumulation at the nozzle opening 211 , when a critical clogging status is identified. For instance, the cleaning mechanism may involve a heating of the nozzle to re-evaporate accumulated material at the nozzle opening.

[0058] Accordingly, in view of the embodiments describe herein, it is to be understood that compared to the state of the art, an improved nozzle monitoringsystem, an improved deposition apparatus, an improved method of detecting clogging of one or more nozzles are provided. In particular, embodiments disclosed herein offer several advantages in efficiently overseeing the performance of nozzles. One advantage is the configuration which allows for monitoring nozzles from the front, which enables the system to detect instances of clogging with high precision. By observing the nozzles from the front perspective, the system can expeditiously identify any blockages or obstructions within the nozzle opening, ensuring prompt intervention to maintain operational integrity.

[0059] Moreover, embodiments of the present disclosure have the advantage that an automated clog detection mechanisms can be provided such that the need for manual nozzle inspections, e.g. through view ports, can be eliminated. By harnessing real-time analysis capabilities, operators can promptly identify and address nozzle issues, mitigating downtime and material wastage. The implementation of the embodiments described herein leads to a significant reduction in downtime and material wastage, ultimately resulting in improved yield and operational efficiency.

[0060] While the foregoing is directed to embodiments of the disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

[0061] In particular, this written description uses examples to disclose the disclosure, including the best mode, and also to enable any person skilled in the art to practice the described subject-matter, including making and using any devices or systems and performing any incorporated methods. While various specific embodiments have been disclosed in the foregoing, mutually nonexclusive features of the embodiments described above may be combined with each other. The patentable scope is defined by the claims, and other examples are intended to be within the scope of the claims if the claims have structural elements that do not differ from the literal language of the claims, or if the claims include equivalent structural elements with insubstantial differences from the literallanguage of the claims.

Claims

WHAT IS CLAIMED:1 . A nozzle monitoring system (100) for monitoring one or more nozzles (210) of a deposition source (200), comprising: a substrate support (110) configured to hold a substrate (10), and a camera (120) configured to monitor a material accumulation at a nozzle opening (211 ) of the one or more nozzles (210), wherein the camera (120) is arranged behind a front side (111 ) of the substrate support (110).

2. The nozzle monitoring system (100) of claim 1 , wherein the substrate support (110) has a reception (113), and wherein the camera (120) is at least partially arranged in the reception (113).

3. The nozzle monitoring system (100) of claim 1 or 2, wherein a front side (114) of the reception (113) is covered by the substrate (10), particularly the substrate being transparent.

4. The nozzle monitoring system (100) of any of claims 1 to 3, wherein a protection glass (123) is arranged in front of the camera (120), particularly wherein a movable protection cover (124) is provided being configured to be moved in front of the protection glass (123).

5. The nozzle monitoring system (100) of any of claims 1 to 4, wherein the camera (120) is arranged inside an atmospheric box (130), particularly the atmospheric box (130) having a transparent front (131 ).

6. The nozzle monitoring system (100) of any of claims 1 to 5, further comprising a communication module (140) configured to send image data recorded by the camera (120) to a data analysis unit (150).

7. The nozzle monitoring system (100) of claim 6, wherein the communication module (140) is provided within a further atmospheric box (131 ).

8. The nozzle monitoring system (100) of any of claims 1 to 7, wherein the communication module (140) is attached to a frame (116) of the substrate support (110).

9. The nozzle monitoring system (100) of any of claims 1 to 8, wherein the camera (120) is a high resolution camera or an infrared camera.

10. The nozzle monitoring system (100) of any of claims 1 to 9, wherein the camera (120) connected to a drive (125) to move the camera along at least one linear trajectory, particularly a first linear trajectory (x) and a second linear trajectory (y).11 . The nozzle monitoring system (100) of any of claims 1 to 10, further comprising an illumination system (160) having a light source (161 ) and an optical fiber (162) for guiding light originating from the light source (161 ) towards the one or more nozzles to be monitored, particularly the optical fiber (162) having one or more openings for directing light to the one or more nozzles to be monitored.

12. The nozzle monitoring system (100) of any of claims 1 to 11 , wherein the substrate support (110) is a substrate carrier for moving the substrate past the deposition source (200).

13. A deposition apparatus (250) for deposition of a material on a substrate (10), comprising: a vacuum chamber (251); one or more deposition sources (200) in the vacuum chamber (251 ); anda nozzle monitoring system (100) according to any of claims 1 to 12 arranged inside the vacuum chamber (251 ).

14. The deposition apparatus (250) of claim 13, wherein the one or more deposition sources (200) comprise an evaporation crucible (220) connected to a distribution assembly (230) with a plurality of nozzles (210) arranged along a line, particularly in a substantially vertical direction.

15. The deposition apparatus (250) of claim 13 or 14, further comprising a transport system (260) for transporting the substrate (10) past the one or more deposition sources (200).

16. A method (300) of detecting clogging of one or more nozzles (210), comprising: monitoring (310) a material accumulation at a nozzle opening (211 ) of the one or more nozzles (210) by using a nozzle monitoring system (100) having a camera (120), being arranged behind a front side (111 ) of a substrate support (110) configured to hold a substrate (10), analyzing (320) image data recorded by the camera (120) by a data analysis unit (150) to obtain status information with respect to an open cross- sectional area of the nozzle opening (211 ), categorizing (330) the status information on the open cross-sectional area into various clogging statuses of nozzle opening (211 ).

17. The method (300) of claim 16, wherein analyzing (320) the image data recorded by the camera (120) by the data analysis unit (150) comprises using a machine learning model.

18. The method of claim 16 or 17, further comprising activating (340) a cleaning mechanism to remove material accumulation at the nozzle opening (211 ), when a critical clogging status is identified.

Images