Substrate processing liquid supply unit and substrate processing apparatus having the same

Abstract

The present invention provides a substrate processing liquid supply unit having a first reservoir and a second reservoir, and forming a flow by maintaining a constant pressure difference between the first reservoir and the second reservoir, and a substrate processing apparatus having the same. The substrate processing liquid supply unit includes a supply reservoir module including a first reservoir supplying a substrate processing liquid to an inkjet head unit ejecting the substrate processing liquid onto a substrate, and a second reservoir recovering the substrate processing liquid unused in the inkjet head unit, and a buffer reservoir module providing the substrate processing liquid to the first reservoir, wherein a constant pressure difference is maintained between the first reservoir and the second reservoir.

Description

Technical Field

[0001] This invention relates to a substrate processing liquid supply unit and a substrate processing apparatus having the same. More specifically, it relates to a substrate processing liquid supply unit that supplies substrate processing liquid to an inkjet head unit that ejects substrate processing liquid onto a substrate, and a substrate processing apparatus having the same. Background Technology

[0002] When performing printing processes (e.g., RGB patterning) on ​​transparent substrates to manufacture display devices such as LCD panels, PDP panels, and LED panels, printing equipment with inkjet head units can be used. Summary of the Invention

[0003] An inkjet head unit can be used to eject ink onto a substrate. A substrate processing apparatus with such an inkjet head unit can typically supply ink to the inkjet head unit using a single reservoir, and can use a pump to restore unused ink in the inkjet head unit back into the reservoir.

[0004] However, since the circulating flow rate can affect the ejection quality of the inkjet head unit, the substrate processing apparatus described above is not suitable for high-flow-rate circulation, and additional methods may be required to prevent the precipitation of particles in the ink.

[0005] The technical problem to be solved by the present invention is to provide a substrate processing liquid supply unit having a first liquid reservoir and a second liquid reservoir, and a flow rate being formed by maintaining a constant pressure difference between the first liquid reservoir and the second liquid reservoir, and a substrate processing apparatus having the same.

[0006] The technical problems of this invention are not limited to those described above. Those skilled in the art can clearly understand other technical problems not mentioned in the following description.

[0007] An aspect of the substrate processing liquid supply unit of the present invention for solving the above-mentioned technical problems includes: a supply reservoir module including a first reservoir for supplying the substrate processing liquid to an inkjet head unit that ejects the substrate processing liquid onto a substrate and a second reservoir for recovering the substrate processing liquid not used in the inkjet head unit; and a buffer reservoir module for supplying the substrate processing liquid to the first reservoir, wherein a constant pressure difference is maintained between the first reservoir and the second reservoir.

[0008] The substrate processing liquid supply unit may further include: a first line connecting the first liquid reservoir and the inkjet head unit; a second line connecting the inkjet head unit and the second liquid reservoir; and a third line connecting the first liquid reservoir and the second liquid reservoir.

[0009] The third line can move ink at a flow rate corresponding to the pressure difference between the first reservoir and the second reservoir.

[0010] The flow rate through the third line may differ from the flow rate through the first line and / or the second line.

[0011] The flow rate through the third line can be greater than the flow rate through the first line and / or the second line.

[0012] The flow rate through the third line can be changed.

[0013] The pressure difference can be the head difference between the first liquid reservoir and the second liquid reservoir.

[0014] The initial pressure difference can be formed by using negative pressure to create different pressures in the first and second reservoirs after the substrate processing liquid is supplied to the first and second reservoirs.

[0015] The first reservoir can be positioned at the same height as the second reservoir, and the buffer reservoir module can be positioned above the first reservoir and / or the second reservoir.

[0016] The substrate processing liquid supply unit may further include: a circulation control module, which circulates the substrate processing liquid recovered to the second reservoir so that it can be supplied to the first reservoir again.

[0017] The circulation control module may include: a pump for circulating the substrate processing liquid from the second reservoir to the first reservoir; a flow meter for measuring the flow rate of the circulating substrate processing liquid; and a filter for filtering the circulating substrate processing liquid.

[0018] The pressure supplied to the cycle control module can be changed.

[0019] The pressure supplied to the circulation control module can be changed based on the water level information of the second reservoir, or based on the ratio between the water level information of the first reservoir and the water level information of the second reservoir.

[0020] The substrate processing liquid supply unit may further include: a water level measuring sensor for measuring water level information, wherein the water level measuring sensor may be disposed in the second liquid reservoir, or may be disposed in both the first liquid reservoir and the second liquid reservoir.

[0021] The substrate processing liquid supply unit may further include a pressure control module that independently controls the pressure of the first liquid reservoir and the pressure of the second liquid reservoir.

[0022] Another aspect of the substrate processing liquid supply unit of the present invention for solving the above-mentioned technical problems includes: a supply reservoir module, comprising a first reservoir for supplying the substrate processing liquid to an inkjet head unit that ejects the substrate processing liquid onto a substrate, and a second reservoir for recovering the substrate processing liquid not used in the inkjet head unit; a buffer reservoir module for supplying the substrate processing liquid to the first reservoir; a circulation control module for circulating the substrate processing liquid recovered to the second reservoir so as to be supplied to the first reservoir again; a first line connecting the first reservoir and the inkjet head unit; a second line connecting the inkjet head unit and the second reservoir; and a third line connecting the first reservoir and the second reservoir, wherein the third line causes ink flow corresponding to the pressure difference between the first reservoir and the second reservoir, and the flow rate through the third line is greater than the flow rate through the first line and / or the second line.

[0023] An aspect of the substrate processing apparatus of the present invention for solving the above-mentioned technical problems includes: an inkjet head unit for spraying substrate processing liquid onto a substrate; and a substrate processing liquid supply unit for supplying the substrate processing liquid to the inkjet head unit, wherein the substrate processing liquid supply unit includes: a supply reservoir module including a first reservoir for supplying the substrate processing liquid to the inkjet head unit and a second reservoir for recovering the substrate processing liquid not used in the inkjet head unit; and a buffer reservoir module for supplying the substrate processing liquid to the first reservoir, wherein a constant pressure difference is maintained between the first reservoir and the second reservoir.

[0024] The substrate processing apparatus may use quantum dot ink as the substrate processing liquid.

[0025] Specific details of other embodiments are included in the detailed description and accompanying drawings. Attached Figure Description

[0026] Figure 1 This is a schematic diagram illustrating the internal structure of a substrate processing apparatus according to an embodiment of the present invention.

[0027] Figure 2 This is a schematic diagram illustrating the internal structure of a substrate processing liquid supply unit constituting a substrate processing apparatus according to an embodiment of the present invention.

[0028] Figure 3 This is a diagram illustrating the movement path of ink within a substrate processing liquid supply unit constituting a substrate processing apparatus according to an embodiment of the present invention.

[0029] Figure 4 It schematically shows the composition. Figure 2 and Figure 3The diagram shows the internal structure of the circulation control module of the substrate processing liquid supply unit.

[0030] Figure 5 It is used to explain the composition Figure 4 The diagram shows a first example of the pump's operation method in the circulating control module.

[0031] Figure 6 It is used to explain the composition Figure 4 The second example diagram shows the operation method of the pump in the circulation control module.

[0032] Figure 7 This is a flowchart illustrating the operation method of a substrate processing liquid supply unit constituting a substrate processing apparatus according to an embodiment of the present invention.

[0033] Explanation of reference numerals in the attached figures

[0034] 100: Substrate processing apparatus; 110: Processing unit

[0035] 120: Maintenance unit; 130: Rack unit

[0036] 140: Inkjet head unit; 150: Substrate processing solution supply unit

[0037] 160: Control Unit; 210: Buffer Reservoir Module

[0038] 220: Liquid reservoir supply module; 221: First liquid reservoir

[0039] 222: Second liquid reservoir; 230: Circulation control module

[0040] 231: Pump 232: Flow meter

[0041] 233: Filter; 240: Pressure control module

[0042] 251: First line 252: Second line

[0043] 253: Third line 260a, 260b: Water level measurement sensor Detailed Implementation

[0044] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. The advantages and features of the present invention, as well as methods for achieving these advantages and features, will be explained by referring to the following description in conjunction with the accompanying drawings. Figure 1The invention becomes clear from the detailed description of the embodiments. However, the invention is not limited to the embodiments disclosed below, but can be implemented in many different forms. These embodiments are provided only to make the disclosure of the invention complete and to fully inform those skilled in the art of the scope of the invention, which is defined only by the scope of the claims. Throughout the specification, the same reference numerals refer to the same constituent elements.

[0045] When an element or layer is referred to as "on" or "above" another element or layer, it includes not only that it is directly above another element or layer, but also that other layers or elements are in between. Conversely, when an element is referred to as "directly" on or directly above another element, it indicates that there are no other elements or layers in between.

[0046] To readily describe the relationship between one element or component and another, as shown in the figure, spatial relative terms such as "below," "below," "lower," "above," and "upper" can be used. It should be understood that, in addition to the orientation shown in the figure, spatial relative terms also include terms indicating the different orientations of the elements during use or operation. For example, when the element shown in the figure is flipped, an element described as "below" or "below" of another element may be located "above" of that element. Therefore, the exemplary term "below" can include both "below" and "above" orientations. An element may also be oriented in another direction, thus allowing the spatial relative terms to be interpreted according to orientation.

[0047] Although the terms "first," "second," etc., are used to describe various elements, constituent elements, and / or parts, these elements, constituent elements, and / or parts are obviously not limited by these terms. These terms are only used to distinguish one element, constituent element, and / or part from another element, constituent element, and / or part. Therefore, the first element, first constituent element, or first part mentioned below can obviously also be a second element, second constituent element, or second part within the technical concept of the present invention.

[0048] The terminology used in this specification is for illustrative purposes and is not intended to limit the invention. In this specification, the singular form includes the plural form unless specifically stated otherwise. The terms "comprises" and / or "comprising" as used in this specification do not exclude the presence or addition of one or more other constituent elements, steps, operations, and / or components in addition to those mentioned.

[0049] Unless otherwise defined, all terms used in this specification (including technical and scientific terms) may be used in the sense that can be commonly understood by one of ordinary skill in the art to which this invention pertains. Furthermore, terms defined in commonly used dictionaries are not to be ideally or excessively interpreted unless explicitly defined otherwise.

[0050] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. When describing the invention with reference to the drawings, identical or corresponding constituent elements are given the same reference numerals, regardless of the reference numerals, and repeated descriptions thereof are omitted.

[0051] This invention relates to a substrate processing liquid supply unit having a first reservoir and a second reservoir, and to a substrate processing apparatus having the same, wherein a flow rate is generated by maintaining a constant pressure difference between the first reservoir and the second reservoir. The invention will now be described in detail with reference to the accompanying drawings.

[0052] Figure 1 This is a schematic diagram illustrating the internal structure of a substrate processing apparatus according to an embodiment of the present invention.

[0053] according to Figure 1 The substrate processing apparatus 100 may include a process processing unit 110, a maintenance unit 120, a gantry unit 130, an inkjet head unit 140, a substrate processing liquid supply unit 150, and a controller 160.

[0054] The substrate processing apparatus 100 processes a substrate G (e.g., a glass substrate) used to manufacture a display device. This substrate processing apparatus 100 can be implemented as a printing device that jettisons substrate processing liquid onto the substrate G using an inkjet head unit 140, and can be implemented as a circulating inkjet device to prevent the nozzles from being clogged by the substrate processing liquid.

[0055] The process processing unit 110 supports the substrate G during the PT operation. This process processing unit 110 can support the substrate G in a non-contact manner. For example, the process processing unit 110 can support the substrate G by suspending it in the air using air. However, this embodiment is not limited to this. The process processing unit 110 can also support the substrate G in a contact manner. The process processing unit 110 can support the substrate G using, for example, a support member with a mounting surface on its upper part.

[0056] Furthermore, the aforementioned PT operation refers to printing on substrate G using a substrate processing solution, where the substrate processing solution is a chemical solution used for printing on substrate G. The substrate processing solution can be, for example, QD (Quantum Dot) ink containing ultrafine semiconductor particles.

[0057] When using an air-supported substrate G, the process unit 110 may include a first stage (1 st Stage 111 and Air Hole 112.

[0058] The first stage 111 is a base, and is configured such that the substrate G can be placed on it. The vents 112 can be formed by penetrating the upper surface of the first stage 111, and can be formed in multiples in the PT zone (PTZone, printing area) of the first stage 111.

[0059] The vent 112 can spray air upwards (to the third direction 30) towards the first stage 111. The vent 112 can thereby suspend the substrate G placed on the first stage 111 in the air.

[0060] On the other hand, although Figure 1 Although not shown, the process unit 110 may also include a clamp. The clamp is used to prevent the substrate G from detaching from the first stage 111 when it moves along the length direction (first direction 10) of the first stage 111. The clamp can prevent the substrate G from detaching from the first stage 111 by clamping the substrate G, and can slide along the guide rail (not shown) while the substrate G is moving.

[0061] The maintenance unit 120 measures the ejection position (i.e., dotting) and whether the substrate processing liquid is ejected on the substrate G. The maintenance unit 120 can measure the ejection position and whether the substrate processing liquid is ejected for each of the multiple nozzles provided in the inkjet head unit 140, and can provide the measurement results obtained in this way to the control unit 160.

[0062] Maintenance unit 120 may include, for example, a second stage (2 nd Stage 121, Third guide rail (3) rd GuideRail)122, First Board (1 st Plate 123, Calibration Board 124, and Vision Module 125.

[0063] The second stage 121, like the first stage 111, is a base and can be arranged parallel to the first stage 111. The second stage 121 can be set to the same size as the first stage 111, but it can also be set to have a size smaller or larger than the first stage 111. The second stage 121 may include an MT zone (maintenance zone) on its upper part.

[0064] The third guide rail 122 guides the movement path of the first plate 123. This third guide rail 122 can be configured as at least one line on the second stage 121 along the length direction (first direction 10) of the second stage 121. The third guide rail 122 can be implemented, for example, as an LM guide system (Linear Motor Guide System).

[0065] On the other hand, although Figure 1 Not shown in the diagram, but the maintenance unit 120 may also include a fourth guide rail (4). th The fourth guide rail, like the third guide rail 122, guides the movement path of the first plate 123, and can be set as at least one line on the second stage 121 along the width direction (second direction 20) of the second stage 121. The fourth guide rail can also be implemented as an LM guide system, just like the third guide rail 122.

[0066] The first plate 123 can move along the third guide rail 122 and / or the fourth guide rail on the second stage 121. The first plate 123 can move parallel to the substrate G along the third guide rail 122, and can move closer to or further away from the substrate G along the fourth guide rail.

[0067] The calibration plate 124 is used to measure the ejection position of the substrate processing liquid on the substrate G. This calibration plate 124 may include alignment marks, scales, etc. and be disposed on the first plate 123, and may be disposed along the length direction (first direction 10) of the first plate 123.

[0068] The vision module 125 acquires image information about the substrate G to measure the ejection position of the substrate processing liquid, whether the substrate processing liquid has been ejected, etc. The vision module 125 may include an area scan camera, a line scan camera, etc., and can acquire image information about the substrate G in real time. On the other hand, in addition to information about the substrate G from which the substrate processing liquid has been ejected, the vision module 125 can also acquire and provide information about the calibration plate 124.

[0069] The vision module 125 can be disposed on the side or bottom of the rack unit 130 to capture images of the substrate G, etc. The vision module 125 can be configured, for example, attached to the side surface of the inkjet head unit 140. However, this embodiment is not limited to this. The vision module 125 can also be disposed on the first plate 123. On the other hand, multiple vision modules 125 can be disposed in the substrate processing apparatus 100, and can be either fixed or movable.

[0070] The frame unit 130 supports the inkjet head unit 140. This frame unit 130 can be disposed above the first stage 111 and the second stage 121 so that the inkjet head unit 140 can spray substrate processing liquid onto the substrate G.

[0071] The rack unit 130 can be arranged on the first stage 111 and the second stage 121 with the width direction (second direction 20) of the first stage 111 and the second stage 121 as its length direction. The rack unit 130 can be arranged along the first guide rail (1 st Guide Rail 170a and Second Guide Rail (2) nd Guide rail 170b moves along the length direction (first direction 10) of the first stage 111 and the second stage 121. On the other hand, the first guide rail 170a and the second guide rail 170b can be arranged outside the first stage 111 and the second stage 121 along the length direction (first direction 10) of the first stage 111 and the second stage 121.

[0072] On the other hand, although Figure 1 Although not shown, the substrate processing apparatus 100 may further include a rack moving unit. The rack moving unit moves the rack unit 130 along a first guide rail 170a and a second guide rail 170b. The rack moving unit may be disposed inside the rack unit 130 and may include a first moving module (not shown) and a second moving module (not shown). The first moving module and the second moving module may be disposed at two ends within the rack unit 130 and may allow the rack unit 130 to slide along the first guide rail 170a and the second guide rail 170b.

[0073] The inkjet head unit 140 ejects the substrate processing liquid into the substrate G in the form of droplets. This inkjet head unit 140 can be disposed on the side or the bottom of the frame unit 130.

[0074] At least one inkjet head unit 140 may be disposed on the rack unit 130. When multiple inkjet head units 140 are disposed on the rack unit 130, the multiple inkjet head units 140 may be arranged in a row along the length direction (second direction 20) of the rack unit 130.

[0075] The inkjet head unit 140 can move along the length direction (second direction 20) of the frame unit 130 to a desired position on the substrate G. However, this embodiment is not limited thereto. The inkjet head unit 140 can move along the height direction (third direction 30) of the frame unit 130, and can also rotate in a clockwise or counterclockwise direction.

[0076] Alternatively, the inkjet head unit 140 can be fixed to the rack unit 130. In this case, the rack unit 130 can be made movable.

[0077] On the other hand, although Figure 1 Although not shown, the substrate processing apparatus 100 may further include an inkjet head moving unit. The inkjet head moving unit causes the inkjet head unit 140 to move linearly or rotate. When the substrate processing apparatus 100 includes multiple inkjet head units 140, the inkjet head moving units may be arranged in the substrate processing apparatus 100 corresponding to the number of inkjet head units 140, so that the multiple inkjet head units 140 operate independently. Alternatively, the inkjet head moving unit may be a single unit in the substrate processing apparatus 100, so that the multiple inkjet head units 140 operate uniformly.

[0078] On the other hand, although Figure 1 Although not shown, the inkjet head unit 140 may include a nozzle plate, multiple nozzles, piezoelectric elements, etc. The nozzle plate constitutes the main body of the inkjet head unit 140. Multiple nozzles (e.g., 128, 256, etc.) can be arranged in multiple rows and columns at predetermined intervals on the lower part of such a nozzle plate, and the number of piezoelectric elements can be set within the nozzle plate to correspond to the number of nozzles. With such a configuration, the inkjet head unit 140 can eject substrate processing liquid onto the substrate G through the nozzles according to the operation of the piezoelectric elements.

[0079] On the other hand, the inkjet head unit 140 can also independently control the amount of substrate processing liquid ejected through each nozzle according to the voltage applied to the piezoelectric element.

[0080] The substrate processing liquid supply unit 150 supplies ink to the inkjet head unit 140. This substrate processing liquid supply unit 150 may include a storage tank and a pressure control module.

[0081] The storage tank stores substrate processing fluid, and the pressure control module regulates the internal pressure of the storage tank. The storage tank can supply an appropriate amount of substrate processing fluid to the inkjet head unit 140 based on the pressure provided by the pressure control module.

[0082] The control unit 160 is used to perform maintenance on the inkjet head unit 140. This control unit 160 can correct the substrate processing liquid ejection position of each nozzle in the inkjet head unit 140 based on the measurement results of the maintenance unit 120, or detect faulty nozzles (i.e., nozzles that do not eject substrate processing liquid) from among multiple nozzles and perform cleaning operations on the faulty nozzles. For this purpose, the control unit 160 can control the operation of each component constituting the substrate processing apparatus 100.

[0083] The control unit 160 can be implemented as a computer or server including a process controller, a control program, an input module, an output module (or a display module), a memory module, etc. As described above, the process controller may include a microprocessor that performs control functions on the various components constituting the substrate processing apparatus 100, and the control program may execute various processes on the substrate processing apparatus 100 according to the control of the process controller. The memory module may store programs, i.e., processing recipes, for executing various processes on the substrate processing apparatus 100 based on various data and processing conditions.

[0084] On the other hand, although Figure 1 Although not shown, the substrate processing apparatus 100 may also include a nozzle inspection unit. The nozzle inspection unit is used to determine whether each nozzle disposed in the inkjet head unit 140 is abnormal. The nozzle inspection unit may utilize, for example, optical inspection to determine whether the nozzle is abnormal.

[0085] The substrate processing liquid supply unit 150 typically has a single storage tank to supply ink to the inkjet head unit 140, and can circulate the ink between the inkjet head unit 140 and the storage tank to prevent the precipitation of particles in the ink.

[0086] However, this type of substrate processing apparatus is unsuitable for high-flow-rate circulation. In this embodiment, to solve this problem, the substrate processing liquid supply unit 150 may have a first reservoir (1 st Reservoir) and second reservoir (2 nd (Reservoir), and flow can be generated by maintaining a constant pressure difference between the first and second reservoirs.

[0087] Figure 2 This diagram schematically illustrates the internal structure of a substrate processing liquid supply unit constituting a substrate processing apparatus according to an embodiment of the present invention. Figure 3 This is a diagram illustrating the movement path of ink within a substrate processing liquid supply unit constituting a substrate processing apparatus according to an embodiment of the present invention.

[0088] according to Figure 2 and Figure 3The substrate processing liquid supply unit 150 may include a buffer reservoir module (BRM) 210, a supply reservoir module (SRM) 220, a circulation control module 230, and a pressure controller module (PCM) 240.

[0089] The buffer reservoir module 210 receives and stores ink from an external ink supply source (not shown). This buffer reservoir module 210 is arranged above the supply reservoir module 220 and serves to fill the supply reservoir module 220 with ink.

[0090] The supply reservoir module 220 stores ink supplied from the buffer reservoir module 210. This supply reservoir module 220 can supply ink to the inkjet head unit 140, and the inkjet head unit 140 can eject the ink supplied by the supply reservoir module 220 onto the substrate G.

[0091] The supply reservoir module 220 may include a first reservoir 221 and a second reservoir 222. Here, the first reservoir 221 may be a feed reservoir for supplying ink to the inkjet head unit 140, and the second reservoir 222 may be a drain reservoir for recovering unused ink in the inkjet head unit 140. Alternatively, the first reservoir 221 may also be a drain reservoir, and the second reservoir 222 may also be a supply reservoir.

[0092] The following explanation will be based on the case where the first reservoir 221 is a supply reservoir and the second reservoir 222 is a recovery reservoir.

[0093] The first reservoir 221 can be connected to the inkjet head unit 140 via the first line 251. The first reservoir 221 can supply ink to the inkjet head unit 140 via the first line 251. The first line 251 can be a supply line.

[0094] The second reservoir 222 can be connected to the inkjet head unit 140 via the second line 252. The second reservoir 222 can recover unused ink in the inkjet head unit 140 via the second line 252. The second line 252 can be a recovery line.

[0095] The first reservoir 221 can be connected to the second reservoir 222 via a third line 253. In this embodiment, in order to maintain a constant pressure difference between the first reservoir 221 and the second reservoir 222, the flow rate corresponding to the pressure difference can be moved from the first reservoir 221 to the second reservoir 222 via the third line 253. The third line 253 can be a bypass line.

[0096] Regarding ink circulation, flow from the first reservoir 221 to the second reservoir 222 is formed by creating a pressure difference between the first reservoir 221 and the second reservoir 222. At this time, the flow rate of ink through the third line 253 can differ from the flow rate of ink through the first line 251 and / or the second line 252. For example, the third line 253 can be configured as the main circulation path for ink, and the first line 251 and / or the second line 252 can be configured as a secondary circulation path for ink, such that the flow rate of ink flowing through the main circulation path can be greater than the flow rate of ink flowing through the secondary circulation path.

[0097] When the third line 253, which is directly connected between the first reservoir 221 and the second reservoir 222, is configured as a bypass line as described above, a low flow rate can be maintained when ink is supplied from the first reservoir 221 to the inkjet head unit 140 via the first line 251, and a high flow rate can be maintained when ink is recovered from the inkjet head unit 140 to the second reservoir 222 via the second line 252.

[0098] Therefore, in this embodiment, by configuring the supply reservoir module 220 as a differential reservoir module (DRM), ink can be prevented from depositing in the nozzle of the inkjet head unit 140, and thus the lifespan of the inkjet head unit 140 can be increased.

[0099] On the other hand, as mentioned above, the pressure difference between the first reservoir 221 and the second reservoir 222 can be the head difference between the ink stored in the first reservoir 221 and the ink stored in the second reservoir 222.

[0100] On the other hand, the flow rate of ink moving from the first reservoir 221 to the second reservoir 222 via the third line 253 can be changed according to the pressure difference between the first reservoir 221 and the second reservoir 222.

[0101] The circulation control module 230 causes ink that has moved to the second reservoir 222 due to unuse in the inkjet head unit 140 to move back to the first reservoir 221. This circulation control module 230 can, as... Figure 4 The device includes a pump 231, a flow meter 232, and a filter 233, and can be implemented, for example, as a pump filter unit (PFU).

[0102] Figure 4 It schematically shows the composition. Figure 2 and Figure 3 The diagram shows the internal structure of the circulation control module of the substrate processing liquid supply unit. See below for reference. Figure 4 Please provide an explanation.

[0103] Pump 231 acts as a pump to move ink from the second reservoir 222 to the first reservoir 221. This pump 231 can be a single unit or multiple units. If multiple pumps are used, they can be arranged in series or in parallel. Alternatively, multiple pumps 231 can be arranged in a mixed series / parallel configuration.

[0104] The ink recovered to the second reservoir 222 via the second line 252 and the third line 253 can be resupplyed to the first reservoir 221 via the pump 231. At this time, in order to maintain a constant pressure difference between the first reservoir 221 and the second reservoir 222, the pressure input to the pump 231 can be changed.

[0105] The pressure of pump 231 can be changed by measuring the water level information of the second reservoir 222 and receiving feedback on that water level information. To measure the water level information of the second reservoir 222, such as... Figure 5 As shown, a water level measuring sensor 260b can be installed in the second liquid reservoir 222. Figure 5 It is used to explain the composition Figure 4 The diagram shows a first example of the pump's operation method in the circulating control module.

[0106] On the other hand, the pressure of pump 231 can also be variably controlled based on the ratio between the water level information of the first reservoir 221 and the water level information of the second reservoir 222. In this case, such as Figure 6 As shown, not only can a water level measuring sensor 260b be installed in the second liquid reservoir 222, but a water level measuring sensor 260a can also be installed in the first liquid reservoir 221. Figure 6 It is used to explain the composition Figure 4 The second example diagram shows the operation method of the pump in the circulation control module.

[0107] Refer again Figure 4 Please provide an explanation.

[0108] Flow meter 232 measures the flow rate of ink moving from the second reservoir 222 to the first reservoir 221. This flow meter 232 can be installed at the rear end of pump 231, i.e., on the pipe (second pump line) connecting pump 231 and the first reservoir 221, or at the front end of pump 231, i.e., on the pipe (first pump line) connecting the second reservoir 222 and pump 231.

[0109] Filter 233 filters the ink moving from the second reservoir 222 to the first reservoir 221. This filter 233 can be located at the rear end of pump 231, just like flow meter 232, or it can be located at the front end of pump 231.

[0110] On the other hand, the filter 233 can be a single unit on the pipeline (first pump line or second pump line) connecting the second reservoir 222 and the first reservoir 221, or it can be multiple units. When multiple filters 233 are installed on the pipeline connecting the second reservoir 222 and the first reservoir 221, the multiple filters 233 can be arranged in series or in parallel on the aforementioned pipeline, or they can be arranged in a mixed series / parallel manner.

[0111] Refer again Figure 2 and Figure 3 Please provide an explanation.

[0112] The pressure control module 240 controls the pressure of the first reservoir 221 and the second reservoir 222 that constitute the supply reservoir module 220. This pressure control module 240 can also control the pressure of the pump 231 that constitutes the circulation control module 230. The pressure control module 240 can be implemented as, for example, a PCM (Pressure Controller Module) including a PCON (Pressure Controller) board.

[0113] The pressure control module 240 can independently control the pressure of the first reservoir 221 and the pressure of the second reservoir 222. In this case, one pressure control module 240 can be connected to both the first reservoir 221 and the second reservoir 222 simultaneously and independently control the pressure of the first reservoir 221 and the second reservoir 222. However, this embodiment is not limited to this. Alternatively, two pressure control modules 240 can be connected to the first reservoir 221 and the second reservoir 222 respectively and independently control the pressure of the first reservoir 221 and the second reservoir 222.

[0114] Next, the operation method of the substrate processing liquid supply unit 150 will be described. The operation method of the substrate processing liquid supply unit 150 described below involves maintaining a constant circulation flow between the supply reservoir module 220 and the inkjet head unit 140.

[0115] Figure 7 This is a flowchart illustrating the operation method of a substrate processing liquid supply unit constituting a substrate processing apparatus according to an embodiment of the present invention. The following refers to... Figure 7 Please provide an explanation.

[0116] First, ink is filled into the first reservoir 221 and the second reservoir 222 to the preset water level (S310).

[0117] Then, the pressure in the first reservoir 221 and the second reservoir 222 is set to their respective preset negative pressure, thereby forming a pressure difference (S320).

[0118] Then, the ink is circulated from the first reservoir 221 to the second reservoir 222 via the third line 253, which is the main circulation path, and the first line 251 and the second line 252, which are sub-circulation paths (S330).

[0119] Then, the water level information of the second liquid reservoir 222 is measured, and the measured value is compared with the preset water level value (reference value) (S340).

[0120] Subsequently, based on the difference between the measured value and the reference value, the amount of ink poured into the second reservoir 222 is supplied to the first reservoir 221 again through the operation of the preset pump 231 (S350).

[0121] On the other hand, it can continuously provide evidence. Figure 7 The control can then include a refilling step to replenish ink when the pressure difference deviates from a preset area.

[0122] Reference above Figures 1 to 7 A substrate processing apparatus and method thereof are described, namely, an inkjet circulation system and method utilizing pressure control. This invention relates to pressure-controlled inkjet circulation. More specifically, it relates to an inkjet circulation system and method for circulating substrate processing liquid by establishing a constant pressure difference between two reservoirs (first reservoir 221 and second reservoir 222).

[0123] Embodiments of the present invention may consist of two reservoirs 221 and 222, an inkjet head unit 140, a pump 231, a pressure control module 240 for individual pressure control, etc., and the flow rate can be generated by maintaining a constant pressure difference between the two reservoirs 221 and 222.

[0124] The present invention can maintain the circulation of ink supplied to the inkjet head unit 140 at a low flow rate, while circulating the ink at a high flow rate in an additional path other than the head supply path. This can prevent the precipitation of particles in the ink, thereby preventing poor ejection of the inkjet head unit 140 and increasing the lifespan of the inkjet head unit 140.

[0125] According to the present invention, the optimal condition for forming a constant pressure difference between the two reservoirs is to form a water head difference in the liquid inside the two reservoirs, and the positive water pressure at the nozzle face of the head can be kept constant by individual pressure control.

[0126] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, those skilled in the art will understand that the present invention can be implemented in other specific forms without changing its technical concept or essential features. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive.

Claims

1. A substrate processing liquid supply unit, comprising: A liquid supply reservoir module includes a first reservoir for supplying substrate processing liquid to an inkjet head unit that ejects substrate processing liquid onto a substrate, and a second reservoir for recovering substrate processing liquid not used in the inkjet head unit. A buffer reservoir module provides the substrate processing liquid to the first reservoir; as well as The third line connects directly to the first and second liquid reservoirs. A constant pressure difference is maintained between the first and second liquid reservoirs. The substrate processing liquid moves from the first reservoir to the second reservoir via the third line at a flow rate corresponding to the pressure difference between the first reservoir and the second reservoir.

2. The substrate processing liquid supply unit according to claim 1 further includes: The first line connects the first liquid reservoir and the inkjet head unit; The second line connects the inkjet head unit and the second liquid reservoir.

3. The substrate processing liquid supply unit according to claim 2, wherein, The substrate processing liquid supply unit uses quantum dot ink as the substrate processing liquid.

4. The substrate processing liquid supply unit according to claim 2, wherein, The flow rate through the third line is different from the flow rate through the first line and / or the second line.

5. The substrate processing liquid supply unit according to claim 4, wherein, The flow rate through the third line is greater than the flow rate through the first line and / or the second line.

6. The substrate processing liquid supply unit according to claim 2, wherein, The flow rate through the third line can be changed.

7. The substrate processing liquid supply unit according to claim 1, wherein, The pressure difference is the head difference between the first liquid reservoir and the second liquid reservoir.

8. The substrate processing liquid supply unit according to claim 1, wherein, The initial pressure difference is formed by creating different pressures in the first and second reservoirs by using negative pressure after the substrate processing liquid is supplied to the first and second reservoirs.

9. The substrate processing liquid supply unit according to claim 1, wherein, The first reservoir is positioned at the same height as the second reservoir, and The buffer reservoir module is positioned on top of the first reservoir and / or the second reservoir.

10. The substrate processing liquid supply unit according to claim 1, further comprising: The circulation control module recirculates the substrate processing liquid recovered to the second reservoir so that it can be supplied to the first reservoir again.

11. The substrate processing liquid supply unit according to claim 10, wherein, The loop control module includes: A pump circulates the substrate processing liquid from the second reservoir to the first reservoir. A flow meter measures the flow rate of the circulating substrate processing liquid; and A filter is used to filter the circulating substrate processing solution.

12. The substrate processing liquid supply unit according to claim 10, wherein, The pressure supplied to the cycle control module can be changed.

13. The substrate processing liquid supply unit according to claim 12, wherein, The pressure supplied to the circulation control module can be changed based on the water level information of the second reservoir, or based on the ratio between the water level information of the first reservoir and the water level information of the second reservoir.

14. The substrate processing liquid supply unit according to claim 10, further comprising: Water level measurement sensor, measures water level information. The water level measurement sensor is located in the second liquid reservoir, or in both the first and second liquid reservoirs.

15. The substrate processing liquid supply unit according to claim 1, further comprising: The pressure control module independently controls the pressure of the first reservoir and the pressure of the second reservoir.

16. A substrate processing liquid supply unit, comprising: A liquid supply reservoir module includes a first reservoir for supplying substrate processing liquid to an inkjet head unit that ejects substrate processing liquid onto a substrate, and a second reservoir for recovering substrate processing liquid not used in the inkjet head unit. A buffer reservoir module provides the substrate processing liquid to the first reservoir; The circulation control module recirculates the substrate processing liquid recovered to the second reservoir so that it can be supplied to the first reservoir again. The first line connects the first liquid reservoir and the inkjet head unit; The second line connects the inkjet head unit and the second liquid reservoir; as well as The third line connects directly to the first and second liquid reservoirs. In this process, ink moves from the first reservoir to the second reservoir via the third line at a flow rate corresponding to the pressure difference between the first and second reservoirs. The flow rate through the third line is greater than the flow rate through the first line and / or the second line.

17. A substrate processing apparatus, comprising: The inkjet head unit sprays the substrate processing liquid onto the substrate. as well as The substrate processing solution supply unit supplies the substrate processing solution to the inkjet head unit. The substrate processing liquid supply unit includes: A liquid supply module includes a first liquid reservoir for supplying the substrate processing liquid to the inkjet head unit and a second liquid reservoir for recovering the substrate processing liquid not used in the inkjet head unit. The buffer reservoir module provides the substrate processing liquid to the first reservoir; and The third line connects directly to the first and second liquid reservoirs. A constant pressure difference is maintained between the first and second liquid reservoirs. The substrate processing liquid moves from the first reservoir to the second reservoir via the third line at a flow rate corresponding to the pressure difference between the first reservoir and the second reservoir.

18. The substrate processing apparatus according to claim 17, wherein, The substrate processing apparatus uses quantum dot ink as the substrate processing liquid.

19. The substrate processing apparatus according to claim 17, wherein, The substrate processing liquid supply unit further includes: The first line connects the first liquid reservoir and the inkjet head unit; The second line connects the inkjet head unit and the second liquid reservoir.

20. The substrate processing apparatus according to claim 19, wherein, The flow rate through the third line is greater than the flow rate through the first line and / or the second line.

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