Liquid discharge device, control method of liquid discharge device, substrate processing apparatus, and article manufacturing method

Abstract

To provide a technique advantageous in reducing time required for recovery processing of a discharge failure nozzle and a liquid used amount.SOLUTION: A liquid discharge device includes: a discharge element which discharges liquid; a driver which drives the discharge element; and a control section which controls the driver. The driver is configured to prepare a plurality of kinds of data sets having pulse patterns in which frequencies are lowered stepwise for each time segment of a prescribed length. In this case, frequencies of the pulse patterns are different from each other between the plurality of kinds of data sets. The control section controls the driver so as to supply each of the plurality of kinds of data sets in order from the pulse pattern having the highest maximum frequency to the discharge element and perform preliminary discharge.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to a liquid ejection apparatus, a control method for a liquid ejection apparatus, a substrate processing apparatus, and a method for manufacturing an article. [Background technology]

[0002] In recent years, when manufacturing various functional elements, attempts have been made to form patterns or films by applying the materials of the functional elements onto a substrate using an inkjet device. Patterning using an inkjet device has the advantages of being highly efficient in terms of material usage because it allows on-demand patterning, being a non-vacuum process that requires relatively small manufacturing equipment, and being able to coat large areas at high speed.

[0003] Incidentally, in the inkjet device described above, during dot pattern formation or while on standby, problems such as poor ejection or impaired quality may occur due to foreign matter adhering inside the flow path or near the nozzle opening, thickening of the ink, settling of ink components, electrophoresis, and the like.

[0004] Patent Document 1 discloses a technique for starting with a small amount of preliminary ejection, then performing a medium amount and a large amount of preliminary ejection until recovery is confirmed. Patent Document 2 discloses discharging ink while increasing or decreasing the drive frequency of the print head in order to remove air bubbles in the print head. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2012-201076 A [Patent Document 2] Patent No. 2659954 Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the recovery method described in Patent Document 1, recovery is performed while changing the amount of preliminary ejection, and there are cases where nozzles cannot be recovered. Also, in the configuration described in Patent Document 2, preliminary ejection is performed while continuously changing the drive frequency for all nozzles, so recovery processing takes a long time and consumes a large amount of ink (liquid).

[0007] The present invention provides a technique that is advantageous for reducing the amount of liquid used and the time required for recovery processing of a nozzle having an ejection failure, for example. [Means for solving the problem]

[0008] According to one aspect of the present invention, there is provided a liquid ejection device comprising an ejection element for ejecting liquid, a driver for driving the ejection element, and a control unit for controlling the driver, wherein the driver is configured to prepare a plurality of types of data sets having pulse patterns in which the frequency gradually decreases for each time segment of a predetermined length, wherein the frequencies of the pulse patterns differ among the plurality of types of data sets, and the control unit controls the driver to supply each of the plurality of types of data sets to the ejection element in order of the highest maximum frequency of the pulse pattern to perform preliminary ejection. Effect of the Invention

[0009] According to the present invention, for example, it is possible to provide a technique that is advantageous for reducing the amount of liquid used and the time required for recovery processing of a discharge-failed nozzle. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram showing a configuration of an inkjet device. [Diagram 2] FIG. 4 is a diagram showing an example of a control configuration for one ejection head. [Diagram 3] 6A and 6B are diagrams for explaining the relationship between a residual signal waveform and a discharge failure state. [Figure 4] 6A and 6B are diagrams for explaining a method of determining a nozzle ejection failure state using a residual signal waveform. [Diagram 5]6A to 6C are diagrams for explaining recovery processing by preliminary ejection. [Figure 6] 5A to 5C are diagrams showing examples of pulse patterns supplied to a nozzle. [Figure 7] FIG. 13 is a diagram showing an example of multiple types of data sets. [Figure 8] 4 is a flowchart showing an operation sequence of the inkjet device. [Figure 9] Schematic diagram showing an example of application of materials for a functional element. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, the embodiments will be described in detail with reference to the attached drawings. Note that the following embodiments do not limit the invention according to the claims. Although the embodiments describe a number of features, not all of these features are essential to the invention, and the features may be combined in any manner. Furthermore, in the attached drawings, the same reference numbers are used for the same or similar configurations, and duplicated descriptions are omitted.

[0012] The configuration and operation principle of an inkjet device 1 (substrate processing device) will be described with reference to FIG. 1. The inkjet device 1, which can function as a substrate processing device for processing substrates such as display panels and semiconductors, deposits a material of a functional element onto a substrate to form a pattern or film. In the specification and drawings, directions are indicated in an XYZ coordinate system in which a plane parallel to a surface on which a substrate 2 is arranged is the XY plane, as shown in FIG. 1. The inkjet device 1 includes a substrate stage 3 that holds and moves a substrate 2 of, for example, a display panel. The substrate 2 may be appropriately selected from a glass substrate or a plastic substrate, depending on the target product to be manufactured. The substrate 2 is typically a plate-shaped member, but is not limited to a specific shape as long as it can function as a substrate. For example, the substrate 2 may be a deformable film or a circular substrate. The substrate 2 on the substrate stage 3 has a pixel area 201 for applying ink to form an array of a large number of display pixels. An evaluation area 202, in which ink is experimentally discharged to evaluate the state of the ink, is arranged on the substrate stage 3. Alternatively, the evaluation area 202 may be provided in a specific region of the substrate 2. In this specification, the term "ink" refers to a liquid used to form a pattern or a film on the substrate 2. In this specification, there is no particular limitation on the components of the ink, but for example, a liquid containing a solute and a solvent for forming an organic film can be used.

[0013] The inkjet device 1 includes a discharge head 5 (liquid discharge device) capable of discharging ink droplets 4 toward a predetermined position on a substrate 2, and an ink supply system 6 that supplies ink to the discharge head 5 from an ink tank 7 that stores ink. The discharge head 5 includes a plurality of nozzles 19 (discharge elements) for discharging ink. The ink tank 7 may be disposed inside the inkjet device 1, or may be disposed outside the inkjet device 1. The inkjet device 1 may also include a recovery unit 8 that performs a cleaning process or the like on the discharge nozzles of the discharge head 5 to recover the discharge characteristics.

[0014] When the substrate 2 is mounted on the substrate stage 3, a placement error may occur. Furthermore, as the substrate 2 undergoes various manufacturing processes, shape distortion may occur in the substrate 2 in the XY directions. For this reason, the inkjet device 1 may include an alignment scope 9 that measures the position of the substrate 2 and the amount of distortion of the substrate 2. In order to perform alignment measurement on the entire surface of the substrate 2, the alignment scope 9 and the substrate stage 3 are driven relatively in the XY directions. That is, the alignment scope 9 and / or the substrate stage 3 are driven in the XY directions. Furthermore, the substrate mounted on the substrate stage 3 has a variation in thickness. Therefore, when ink is discharged by the discharge head 5 while scanning the substrate stage 3 in the Y direction, the landing position of the ink droplets on the substrate 2 may vary due to the variation in thickness of the substrate 2. For this reason, the inkjet device 1 may also include a height sensor 10 that measures the position (height) of the substrate 2 in the Z direction. In order to perform height measurement on the entire surface of the substrate 2, the height sensor 10 and the substrate stage 3 are driven relatively in the XY directions. That is, the height sensor 10 and / or the substrate stage 3 are driven in the XY directions.

[0015] The main control unit 11 controls each unit of the inkjet device 1 to supervise patterning on the substrate 2. The main control unit 11 can be configured, for example, by a PLD (abbreviation for Programmable Logic Device) such as an FPGA (abbreviation for Field Programmable Gate Array), or an ASIC (abbreviation for Application Specific Integrated Circuit), or a general-purpose computer with a built-in program, or a combination of all or part of these.

[0016] In one example, a plurality of ejection heads 5 are arranged in each of the X direction and the Y direction, and the ejection of ink droplets from each ejection head is individually controlled to apply ink in a desired distribution to a pixel area 201 on the substrate 2. FIG. 2 shows an example of a control configuration of one ejection head 5. The ejection head 5 may include a plurality of nozzles 19. Each of the plurality of nozzles 19 constitutes an ejection element including a piezoelectric element (ejection energy generating element). Each of the plurality of nozzles 19 is connected to a driver D that drives the piezoelectric element via a flexible cable F. The driver D is connected to an ejection control unit C (control unit). The ejection control unit C sends a command (recovery process command) to the driver D to recover an abnormal nozzle among the plurality of nozzles 19. The driver D applies a drive signal to the piezoelectric element of the abnormal nozzle in response to the received command and executes the recovery process. The function of the ejection control unit C may be realized by the main control unit 11.

[0017] During the formation of a dot pattern using multiple nozzles 19 or while waiting, problems such as poor ejection or quality degradation can occur due to foreign matter adhering to the inside of the flow path or near the nozzle opening, thickening of the ink, settling of ink components, electrophoresis, etc. These problems are caused by the combined effects of various factors such as ejection time, flow path shape, distance from the electrode, and waiting time before ejection. The severity of the problem can vary from nozzle to nozzle.

[0018] The recovery unit 8 is used for recovery from foam entrapment or severe nozzle clogging that cannot be recovered by preliminary ejection. However, recovery processing using the recovery unit 8 takes a long time, and a very large amount of ink is used in the recovery processing. For this reason, recovery processing using the recovery unit 8 is only carried out at times set as regular maintenance. In normal operation, preliminary ejection from multiple nozzles 19 is carried out in the preliminary ejection area 20 as appropriate, and nozzles with ejection problems are restored to normal.

[0019] The ejection failure state of each nozzle can be confirmed using a related signal (residual signal waveform) measured after the generation of a specific pressure wave. Specifically, the ejection control unit C operates the piezoelectric element by providing a specific pulse signal to the piezoelectric element via the driver D. The operation of the piezoelectric element generates a specific pressure wave in the piezoelectric element. If the piezoelectric element is normal, this pressure wave will cause ink to drip from the nozzle. At this time, the pressure wave generated by the piezoelectric element causes distortion in the piezoelectric element, and an electrical signal corresponding to this distortion is generated. This electrical signal is called a "residual signal." The ejection control unit C detects this electrical signal and judges the ejection failure state of the piezoelectric element based on the detected electrical signal.

[0020] An example of a residual signal waveform is shown in Figure 3(a). The horizontal axis represents time, and the vertical axis represents potential. The residual signal waveform shown in Figure 3(a) is a reference signal waveform that indicates the state of a nozzle capable of stable ejection, and if a signal waveform equivalent to this is obtained, the nozzle is determined to be in a normal state. As the nozzle's ejection failure progresses, this waveform changes as shown below.

[0021] As the nozzle ejection failure progresses, the residual signal waveform changes from the solid line to the dashed line, as shown in FIG. 3(b). Specifically, the first peak position is T 0 From T 1 , T 2 and the signal period becomes longer. As the discharge failure progresses, the residual signal waveform transitions from dashed line 1 to dashed line 2. When preliminary ejection is performed at an appropriate frequency on the nozzle with this discharge failure and the nozzle returns to a normal state, the residual signal waveform returns to the original reference waveform (solid line waveform) in Figure 3(a).

[0022] The recovery process using preliminary ejection will be described with reference to Figures 4(a) to (d). Figure 4(a) shows the residual signal waveforms indicating the defective ejection state for each of the five nozzles, nozzles A to E. The defective ejection state differs for each nozzle, and as shown in Figure 4(a), the residual signal waveforms also differ for each nozzle. The process for recovering the defective ejection state, which differs for each nozzle as shown in Figure 4(a), to a normal state (reference waveform) as shown in Figure 3(a) by preliminary ejection is carried out according to the following procedure. (1) A preliminary ejection frequency suited to the defective state of a nozzle is determined, and a pulse signal of that frequency is applied to the nozzle. (2) The pre-ejection frequency is applied in order starting from the nozzle with the worst nozzle failure.

[0023] By carrying out the above two procedures, it is possible to recover nozzles with discharge problems. In one example, when there are multiple nozzles with different discharge problems as shown in FIG. 4(a), the discharge control unit C classifies the discharge problems into multiple (three) groups as shown in FIG. 4(b), (c), and (d). The discharge control unit C then performs preliminary ejection for each group via the driver D at a frequency suited to the discharge problem. For example, the discharge control unit C performs preliminary ejection for each group at a frequency suited to the discharge problem as shown in FIG. 4(d). 2 If the first peak is within the area I including T, the nozzle E is determined to be in a severe discharge failure state. 1 If the nozzle D is within the area II including T 0 If the nozzles are within area III, which includes nozzles A, B, and C, then they are determined to be in a state of minor ejection defects. Note that since nozzle A is in a normal state, the waveform for nozzle A in Figure 4(b) is the same as the reference waveform in Figure 4(a).

[0024] In this way, the discharge control unit C determines the discharge failure state based on the position of the first peak in the residual signal waveform, and controls the driver D to perform preliminary discharge by giving a pulse signal of a frequency suitable for the discharge failure state to the nozzle. High frequency preliminary discharge is suitable for a nozzle with severe discharge failure in which the first peak of the residual signal waveform is in area I. Medium frequency preliminary discharge is suitable for a nozzle with moderate discharge failure in which the first peak of the residual signal waveform is in area II. Low frequency preliminary discharge is suitable for a nozzle with mild discharge failure in which the first peak of the residual signal waveform is in area III. In one example, the high frequency is a frequency within the range of 10 kHz to 50 kHz. The medium frequency is a frequency within the range of 1 kHz to 10 kHz. The low frequency is a frequency within the range of 100 Hz to 1 kHz.

[0025] With reference to Figs. 5(a) to (d), a procedure for recovering nozzle E in a severe discharge failure state shown in Fig. 4(d) will be described. Fig. 5(a) shows the same signal waveform as Fig. 4(d). As shown in Fig. 5(a), the first peak position of the signal waveform indicating the defective state of nozzle E is in area I, so high-frequency preliminary discharge is first performed. As a result of this high-frequency preliminary discharge, the signal period of the residual signal waveform becomes shorter and the first peak position is advanced, as shown in Fig. 5(b), and the residual signal waveform transitions to area II. In response to the transition of the first peak position to area II, medium-frequency preliminary discharge is performed. As a result of this medium-frequency preliminary discharge, the signal period of the residual signal waveform becomes shorter and the first peak position is advanced, as shown in Fig. 5(c), and the residual signal waveform transitions to area III. In response to the transition of the first peak position to area III, low-frequency preliminary discharge is performed. As a result of this low-frequency preliminary discharge, the residual signal waveform returns to the reference waveform as shown in Fig. 5(d), and the recovery process is completed.

[0026] According to the recovery processes shown in Figures 5(a) to (d) above, the degree of recovery by each recovery process can be predicted without checking the residual signal waveform. For example, the driver D may perform preliminary ejection using a data set (a combination of high, medium, and low ejection frequencies) having a pulse pattern in which the frequency is gradually decreased for each time segment of a predetermined length, as shown in Figure 6. In the example of Figure 6, the pulse pattern may include the following pulse train: (1) a first pulse train of high frequency (e.g., 50 kHz) corresponding to a severe nozzle malfunction during a first time segment; (2) a second pulse train of a medium frequency (e.g., 5 kHz) corresponding to a moderate nozzle failure in a second time segment following the first time segment; (3) A third pulse train of low frequency (e.g., 500 Hz) corresponding to minor nozzle malfunction in a third time segment following the second time segment.

[0027] However, when the same data set shown in FIG. 6 is applied to a plurality of nozzles each having a different discharge failure state, the recovery ability is low, especially for nozzles whose discharge failure state and preliminary discharge frequency do not match. In order to obtain the same recovery effect for a plurality of nozzles each having a different discharge failure state, the driver D prepares a plurality of types of data sets having different frequencies in advance, as shown in FIG. 7. That is, the frequencies of the pulse patterns are different between the plurality of types of data sets. Each data set may be stored in an internal or external memory of the driver D and read out for use, or each data set may be generated as needed. The discharge control unit C controls the driver D to supply each of the plurality of types of data sets to the nozzle in order of the highest frequency of the pulse pattern to perform preliminary discharge. In the example of FIG. 7, set 1 includes a 50 kHz pulse train in the first time segment, a 5 kHz pulse train in the second time segment, and a 500 Hz pulse train in the third time segment. Set 2 includes a 30 kHz pulse train in the first time segment, a 3 kHz pulse train in the second time segment, and a 300 Hz pulse train in the third time segment. Set 3 includes a 10 kHz pulse train in the first time segment, a 1 kHz pulse train in the second time segment, and a 100 Hz pulse train in the third time segment. By supplying the pulse patterns to the nozzle in descending order of maximum frequency, i.e., set 1, set 2, and set 3, and performing preliminary ejection, the nozzle can be reliably restored in a short time.

[0028] In the examples of Figures 6 and 7, the signals constituting each set have three different frequencies, but this is not limited to this. The signals constituting each set may have two different frequencies, or four or more different frequencies. When the nozzle recovery state is checked and multiple unrecovered nozzles are found, the number of different frequencies of the signals constituting each set may be increased.

[0029] With reference to FIG. 8, the operation sequence of the inkjet device 1 will be described. In S801, the main control unit 11 controls a substrate transport device (not shown) to carry the substrate 2 into the inkjet device 1. In S802, the discharge control unit C performs recovery judgment for the multiple nozzles 19 of the discharge head 5. The recovery judgment is performed by judging whether or not the first peak position of the residual signal waveform is equivalent to that of the reference waveform. Specifically, the discharge control unit C applies a specific pulse signal to the nozzle via the driver D to operate the nozzle, and detects an electric signal corresponding to the distortion of the nozzle caused by a pressure wave generated by the operation of the nozzle as a residual signal. Thereafter, the discharge control unit C judges the nozzle's discharge failure state based on a comparison between the first peak position of the residual signal waveform and the peak position of the reference waveform. Note that the recovery judgment for the multiple nozzles 19 may be performed before ink discharge. If there is a nozzle that is judged to be discharge failure in this recovery judgment, in S803, the discharge control unit C executes the above-mentioned nozzle recovery process for the nozzle. That is, in the nozzle recovery process, the discharge control unit C acquires multiple types of data sets having pulse patterns with a stepwise decreasing frequency for each time segment of a predetermined length. Here, the frequencies of the pulse patterns differ between the multiple types of data sets. The discharge control unit C then supplies each of the multiple types of data sets to the nozzle in order of the highest pulse pattern frequency, and performs preliminary discharge. Note that the nozzle recovery determination and recovery process described above may be performed by the main control unit 11.

[0030] In S804, the main control unit 11 controls the substrate stage 3 and the alignment scope 9 to perform alignment measurement of the substrate 2. In S805, the main control unit 11 controls the substrate stage 3 and the height sensor 10 to perform height measurement of the substrate 2. Note that the order of the alignment measurement in S804 and the height measurement in S805 may be reversed. Information regarding the position, distortion amount, and height of the substrate 2 obtained by the alignment measurement and the height measurement is stored, for example, in a memory in the main control unit 11. The main control unit 11 obtains ejection control information based on pixel data including information such as pixel arrangement and pixel size formed on the substrate 2. The ejection control information includes information indicating a target ink application distribution in the pixel area 201 and the evaluation area 202 on the substrate 2.

[0031] In S806, the discharge control unit C performs a recovery determination for the multiple nozzles 19 of the discharge head 5. The recovery determination is performed by determining whether or not the first peak position of the residual signal waveform is equivalent to that of the reference waveform, as described above. If this recovery determination finds that a nozzle has a discharge defect, in S807 the discharge control unit C executes the nozzle recovery process described above for that nozzle.

[0032] In S808, the main control unit 11 controls the ejection of ink droplets by the ejection head 5 based on the target application distribution via the ejection control unit C while synchronously driving the ejection head 5 and the substrate stage 3. In order to form a large number of functional elements on the substrate using the inkjet device 1, the material of the functional elements is applied by scanning the application area where the ink is applied and the ejection head 5 relatively. FIG. 9 shows a schematic diagram for explaining the application of the material of such functional elements. In FIG. 9, the substrate surface 101 is the surface of the substrate 2 on which the functional elements 102 are formed. Arrows 103, 104, 105, and 106 indicate the scanning direction. Since FIG. 9 is a schematic diagram, only 7×5 functional elements 102 are shown, but in reality, a very large number of functional elements can be formed.

[0033] In S809, the main control unit 11 determines whether or not the ejection to the target coating distribution is completed based on the ejection control information. If the ejection is not completed, the process returns to S806, and if the ejection is completed, the process proceeds to S810. In S810, the main control unit 11 controls a substrate transport device (not shown) to transport the substrate 2 out of the inkjet device 1.

[0034] <Embodiment of the article manufacturing method> The article manufacturing method according to the embodiment of the present invention is suitable for manufacturing articles such as display panels for organic EL displays, microdevices such as semiconductor devices, and elements having fine structures. The article manufacturing method according to the present embodiment includes a step of discharging a liquid onto a substrate using the inkjet device to form a discharged liquid film, a step of drying the substrate on which the discharged liquid film has been formed to obtain a substrate on which a dry film has been formed, and a step of manufacturing an article from the substrate on which the dry film has been formed. Furthermore, the article manufacturing method includes other well-known steps (baking, cooling, cleaning, oxidation, film formation, deposition, doping, flattening, etching, resist stripping, dicing, bonding, packaging, etc.). The article manufacturing method according to the present embodiment is advantageous in at least one of the performance, quality, productivity, and production cost of the article compared to conventional methods.

[0035] The disclosure of the present specification includes at least the following liquid ejection apparatus, a control method for a liquid ejection apparatus, a substrate processing apparatus, and an article manufacturing method. (Item 1) An ejection element that ejects liquid; A driver that drives the ejection elements; A control unit that controls the driver; Equipped with The driver is configured to prepare a plurality of types of data sets having a pulse pattern in which the frequency is gradually decreased for each time segment of a predetermined length, wherein the frequencies of the pulse patterns are different from each other among the plurality of types of data sets; the control unit controls the driver to supply each of the plurality of types of data sets to the ejection elements in order from highest to lowest maximum frequency of a pulse pattern, thereby performing preliminary ejection. A liquid ejection device comprising: (Item 2) The plurality of types of data sets include: A first data set having a pulse pattern in which the frequency is gradually decreased for each time segment of the predetermined length; a second data set having a pulse pattern in which the frequency is gradually decreased for each time segment of the predetermined length, the second data set having a frequency lower than the frequency of the first data set in each time segment; a third data set having a pulse pattern in which the frequency is gradually decreased for each time segment of the predetermined length, the third data set having a frequency lower than the frequency of the second data set in each time segment; 2. The liquid ejection device according to item 1, comprising: (Item 3) The pulse pattern is a first series of high frequency pulses corresponding to a severe ejection failure of the ejection element during a first time segment; a second train of medium frequency pulses corresponding to moderate ejection failure of the ejection element in a second time segment following the first time segment; a third pulse train having a lower frequency corresponding to minor ejection failures of the ejection elements in a third time segment following the second time segment; 3. The liquid ejection device according to item 1 or 2, comprising: (Item 4) The liquid ejection device described in item 3, characterized in that the high frequency is a frequency within a range of 10 kHz to 50 kHz, the medium frequency is a frequency within a range of 1 kHz to 10 kHz, and the low frequency is a frequency within a range of 100 Hz to 1 kHz. (Item 5) the ejection element includes a piezoelectric element; The control unit is A specific pulse signal is applied to the piezoelectric element via the driver to operate the piezoelectric element, and an electrical signal corresponding to the distortion of the piezoelectric element caused by a pressure wave generated by the operation of the piezoelectric element is detected; when it is determined that the ejection element is defective based on the detected electrical signal, the driver is controlled to perform preliminary ejection using the plurality of types of data sets. 5. The liquid ejection device according to any one of items 1 to 4. (Item 6) A method for controlling a liquid ejection device including an ejection element that ejects liquid, comprising: acquiring a plurality of types of data sets having a pulse pattern whose frequency is gradually decreased for each time segment of a predetermined length, wherein the frequencies of the pulse patterns differ from one another among the plurality of types of data sets; supplying each of the plurality of types of data sets to the ejection elements in order of the highest maximum frequency of the pulse pattern to perform preliminary ejection; A control method comprising the steps of: (Item 7) A substrate processing apparatus for processing a substrate, a stage for holding and moving the substrate; 6. The liquid ejection apparatus according to any one of items 1 to 5, which ejects liquid onto the substrate held by the stage; A substrate processing apparatus comprising: (Item 8) Discharging a liquid onto a substrate using the substrate processing apparatus according to item 7; processing the substrate onto which the liquid has been discharged; and producing an article from the processed substrate.

[0036] The invention is not limited to the above-described embodiments, and various modifications and variations are possible without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention. [Explanation of symbols]

[0037] 1: inkjet device (substrate processing device), 2: substrate, 3: substrate stage, 5: ejection head (liquid ejection device), 9: alignment scope, 10: height sensor, 11: main control unit, 19: nozzle (ejection element)

Claims

1. an ejection element that ejects liquid; a driver that applies a drive signal to the ejection element to drive the ejection element; a control unit that controls the driver; Equipped with the drive signal includes a plurality of types of data sets having pulse patterns whose frequency decreases stepwise for each time segment of a predetermined length, wherein the frequencies of the pulse patterns differ from one another among the plurality of types of data sets; the control unit controls the driver to supply each of the plurality of types of data sets to the ejection elements in order from highest to lowest pulse pattern frequency, thereby performing preliminary ejection. A liquid ejection device characterized by:

2. The plurality of types of data sets include: a first data set having a pulse pattern in which the frequency decreases stepwise for each time segment of the predetermined length; a second data set having a pulse pattern in which the frequency decreases stepwise for each time segment of the predetermined length, the second data set having a frequency lower than the frequency of the first data set in each time segment; The liquid ejection device according to claim 1 , further comprising:

3. The plurality of types of data sets further include: a third data set having a pulse pattern in which the frequency decreases stepwise for each of the predetermined length time segments, the third data set having a frequency lower than the frequency of the second data set in each time segment; 3. The liquid ejection device according to claim 2.

4. The pulse pattern is a first pulse train in a first time segment; a second pulse train in a second time segment following the first time segment, the second pulse train having a frequency lower than the frequency of the first pulse train; The liquid ejection device according to claim 1 , further comprising:

5. The pulse pattern a third pulse train in a third time segment following the second time segment, the third pulse train having a frequency lower than that of the second pulse train; 5. The liquid ejection device according to claim 4.

6. 6. The liquid ejection device according to claim 5, wherein the frequency of the first pulse train is within a range of 10 kHz to 50 kHz, the frequency of the second pulse train is within a range of 1 kHz to 10 kHz, and the frequency of the third pulse train is within a range of 100 Hz to 1 kHz.

7. the ejection element includes a piezoelectric element; The control unit A specific pulse signal is applied to the piezoelectric element via the driver to operate the piezoelectric element, and an electrical signal corresponding to the distortion of the piezoelectric element caused by a pressure wave generated in association with the operation of the piezoelectric element is detected; When it is determined that the ejection element is defective based on the detected electrical signal, the driver is controlled to perform preliminary ejection using the plurality of types of data sets. The liquid ejection device according to claim 1 .

8. The liquid ejection device is a device capable of ejecting the liquid onto a substrate, the control unit controls the driver to perform preliminary ejection in an area where the substrate is not provided. The liquid ejection device according to claim 1 .

9. A method for controlling a liquid ejection device including an ejection element that ejects liquid, comprising: acquiring a plurality of types of data sets each having a pulse pattern whose frequency decreases stepwise for each time segment of a predetermined length; wherein the frequencies of the pulse patterns differ from one another among the plurality of types of data sets; a step of supplying each of the plurality of types of data sets to the ejection elements in order of the highest pulse pattern frequency to perform preliminary ejection; A control method comprising:

10. A substrate processing apparatus for processing a substrate, a stage that holds and moves the substrate; a liquid ejection apparatus according to claim 1 , which ejects liquid onto the substrate held by the stage; A substrate processing apparatus comprising:

11. Discharging a liquid onto a substrate using the substrate processing apparatus according to claim 10; processing the substrate onto which the liquid has been discharged; and manufacturing an article from the processed substrate.

Images