JP2008132398A - Discharge method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a discharge method in which the discharge amount can be controlled with high precision. <P>SOLUTION: The method for discharging a liquid droplet of a functional liquid to a workpiece from a nozzle of a liquid droplet discharge head comprises: a preliminary discharge step S6 of discharging the liquid droplet to a preliminary discharge area from the nozzle and heating the nozzle; a measurement discharge step S8 of discharging the liquid droplet to a discharge amount measuring part from the nozzle; measurement steps S7, S9 of measuring the amount of the functional liquid to be discharged from the liquid droplet discharge head by the discharge amount measuring part; a discharge amount adjustment step S10 of adjusting the amount of the liquid droplet to be discharged from the nozzle; and a plotting step S11 of discharging the liquid droplet to the workpiece from the nozzle. At the preliminary discharge step S6, the discharge of the liquid droplet is continued until the nozzle temperature becomes almost same as the plotting nozzle temperature being the nozzle temperature at the plotting step S11. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a discharge method for discharging using a droplet discharge device.

  2. Description of the Related Art Conventionally, as a method for ejecting droplets onto a workpiece, a method for ejecting droplets using an ink jet droplet ejecting apparatus is known. The droplet discharge device moves along a table on which a workpiece such as a substrate is placed and the workpiece is moved in one direction, and a guide rail arranged in a direction perpendicular to the moving direction of the table at a position above the table. And a carriage. An ink jet head (hereinafter referred to as a droplet discharge head) is disposed on the carriage, and droplets are discharged onto the workpiece and applied.

  Various materials are used for the functional liquid that is discharged and applied to the workpiece as droplets. Many functional fluids change in viscosity with temperature, and fluid resistance changes as the viscosity changes. As the fluid resistance changes, the flow velocity of the functional liquid flowing through the flow path in the droplet discharge head changes. By changing the flow rate of the functional liquid, the discharge amount per dot fluctuates, and it is difficult to apply a desired amount of the functional liquid.

  In order to solve this problem, Patent Document 1 discloses a method for controlling the discharge amount per dot. According to this, the drive waveform for driving the piezoelectric element that pressurizes the cavity of the droplet discharge head, the drive voltage, and the temperature of the liquid to be discharged are controlled. Further, in order to control the temperature of the liquid, heaters are installed in the droplet discharge head, the supply pipe, and the tank.

JP 2003-26679 A

  When pressurizing the cavity of the droplet discharge head, a part of the energy applied to the operation of the piezoelectric element is converted into heat, which causes the temperature of the droplet discharge head to rise. In addition, when the piezoelectric element is not driven, the piezoelectric element does not generate heat, and the droplet discharge head dissipates heat, which causes the temperature to fluctuate. The method of heating a droplet discharge head, a supply pipe, and a tank using a heater is effective in warming the apparatus and setting the liquid temperature to a predetermined temperature in a short time. On the other hand, in the method in which the temperature fluctuation due to the operation of the droplet discharge head is made constant by the heater heating, there is a case where control following the liquid temperature fluctuation cannot be performed.

  Since the discharge amount is affected by temperature when drawing, the head temperature before drawing needs to be the same head temperature as during drawing.

  The present invention has been made paying attention to such conventional problems, and an object thereof is to provide a discharge method capable of controlling the discharge amount with high accuracy.

  In order to solve the above problems, a discharge method of the present invention is a discharge method for discharging a functional liquid from a nozzle, including a preliminary discharge step of discharging a functional liquid from a nozzle to a preliminary discharge region, and a functional liquid from the nozzle. In the preliminary discharge step, the functional liquid is discharged until the nozzle reaches a temperature substantially the same as that in the discharge step.

  According to this discharge method, drawing is performed by discharging functional liquid as droplets from a nozzle onto a workpiece. This discharge method has a preliminary discharge step and a discharge step.

  In the preliminary discharge step, droplets are discharged from the nozzles to the preliminary discharge region. At this time, droplets are discharged until the nozzle temperature is substantially the same as the drawing nozzle temperature, which is the temperature of the nozzle in the discharge process. In the ejection step, droplets are ejected from the nozzle onto the workpiece while the nozzle temperature is substantially the same as the drawing nozzle temperature.

  Since the viscosity of the functional liquid changes when the temperature changes, pressure is applied to the functional liquid in the droplet discharge head, and the fluid resistance changes when passing through a nozzle or other flow path, causing the liquid to be discharged from the nozzle. The amount of liquid discharged changes.

  In the preliminary discharge process, the nozzle is at the drawing nozzle temperature. In the discharging step, droplets are discharged from the nozzle having the drawing nozzle temperature. As a result, it is possible to discharge with less fluctuation of the discharge amount when discharging.

  The discharge method of the present invention further includes a discharge amount adjustment step of adjusting the discharge amount of the functional liquid discharged from the nozzle.

  According to this discharge method, the discharge amount adjusting step is included. In the discharge amount adjustment step, the discharge amount of droplets discharged from the nozzle is adjusted. Accordingly, the discharge amount can be controlled with high accuracy and discharged.

  The discharge method of the present invention includes a preliminary measurement step of measuring the number of discharges until the nozzle reaches the temperature in the discharge step after discharging the functional liquid, and in the preliminary discharge step, the functional liquid of the discharge number is discharged. It is characterized by that.

  This discharge method has a preliminary measurement step. In the preliminary measurement step, the number of ejections from when the nozzle ejects droplets to the drawing nozzle temperature is measured. Then, in the preliminary ejection step, the number of droplets ejected until the drawing nozzle temperature is reached is ejected. Therefore, even when the nozzle temperature is the nozzle temperature when no discharge is performed for a long time, the drawing nozzle temperature in the discharge process can be set in the preliminary discharge process.

  The ejection method of the present invention is characterized in that in the preliminary ejection process, ejection is performed using substantially the same ejection pattern as the ejection pattern of functional liquid ejection and ejection stop in the ejection process.

  According to this discharge method, when droplets are discharged from the nozzle in the preliminary discharge step, the discharge pattern of discharge and discharge stop is discharged using substantially the same discharge pattern as the discharge pattern in the discharge step. .

  In the preliminary ejection step and the ejection step, ejection is performed with substantially the same ejection pattern, so that the droplet ejection head has substantially the same temperature distribution. Accordingly, droplets are ejected from the nozzles in the droplet ejection head having the same temperature distribution as the ejection process. As a result, discharge can be performed with little variation in the discharge amount in the discharge process.

  The discharge method of the present invention is a preliminary process for forming a preliminary discharge pattern of functional liquid discharge and discharge stop, which is formed at substantially the same ratio as the ratio of the functional liquid discharge time and the discharge stop time in the discharge process. A discharge pattern forming step is provided, and the preliminary discharge step is characterized by discharging using a preliminary discharge pattern.

  According to this discharge method, a preliminary discharge pattern forming step is provided. In the preliminary discharge pattern forming step, a preliminary discharge pattern having a ratio substantially equal to the ratio of the droplet discharge time and the discharge stop time in the discharge step is formed. In the preliminary discharge step, discharge is performed using a preliminary discharge pattern.

  In the preliminary ejection pattern forming step, it is possible to form a preliminary ejection pattern having the number of ejections corresponding to the number of ejections required for the nozzle temperature to become the drawing nozzle temperature in the preliminary ejection. In the ejection process, when the number of ejections when discharging and drawing droplets is large, in the preliminary ejection process, when ejecting using the ejection pattern in the ejection process, the number of ejections ejected in the preliminary ejection is too large There is. In the preliminary ejection pattern, the number of ejections suitable for preliminary ejection can be set. Therefore, when the number of ejections in the ejection process is more than the number of ejections required for the nozzle temperature to become the drawing nozzle temperature in the preliminary ejection, the preliminary ejection pattern is compared with the case where the drawing ejection pattern is used in the preliminary ejection process. When used, the nozzle temperature can be made the drawing nozzle temperature with a smaller number of ejections. As a result, since the number of discharges required for the preliminary discharge can be set optimally, the preliminary discharge can be performed in a resource-saving manner.

  In the discharge method of the present invention, the preliminary discharge step determines whether or not to discharge the functional liquid from the nozzle based on the nozzle temperature measurement step for measuring the nozzle temperature and the nozzle temperature measured in the nozzle temperature measurement step. The preliminary discharge step is characterized in that the functional liquid is discharged so that the nozzle temperature reaches a predetermined temperature while repeating the nozzle temperature measurement step and the temperature determination step.

  According to this discharge method, a nozzle temperature measuring step and a temperature determining step are provided. In the nozzle temperature measuring step, the nozzle temperature of the droplet discharge head is measured. In the temperature determination step, it is determined whether the nozzle temperature measured in the nozzle temperature measurement step has reached a predetermined temperature. In the temperature determination step, when the nozzle temperature does not reach a predetermined temperature, a droplet is ejected from the nozzle. Then, the nozzle temperature measurement process, the temperature determination process, and the discharge are repeated so that the nozzle temperature reaches a predetermined temperature.

  The nozzle temperature is measured, and when the nozzle temperature is lower than a predetermined temperature, droplets are ejected from the nozzle to raise the nozzle temperature. Since this is repeated until the nozzle temperature reaches a predetermined temperature, the nozzle temperature can be reliably set to the predetermined temperature.

Embodiments of the present invention will be described below with reference to the drawings.
In addition, each member in each drawing is illustrated with a different scale for each member in order to make the size recognizable on each drawing.

(First embodiment)
In the present embodiment, an example of a characteristic discharge method of the present invention, in which a droplet discharge device and a droplet are discharged and drawn using the droplet discharge device, will be described with reference to FIGS.

(Droplet discharge device)
First, a droplet discharge device 1 that discharges and applies droplets to a workpiece will be described with reference to FIGS. There are various types of droplet discharge devices, but a device using an ink jet method is preferable. The ink jet method is suitable for microfabrication because it can discharge minute droplets.

  FIG. 1 is a schematic perspective view showing the configuration of the droplet discharge device. A functional liquid is discharged and applied by the droplet discharge device 1. As shown in FIG. 1, the droplet discharge device 1 includes a base 2 formed in a rectangular parallelepiped shape. In the present embodiment, the longitudinal direction of the base 2 is the Y direction, and the direction orthogonal to the Y direction is the X direction.

  On the upper surface 2a of the base 2, a pair of guide rails 3a, 3b extending in the Y direction is provided so as to protrude over the entire width in the Y direction. On the upper side of the base 2, a stage 4 constituting a scanning means provided with a linear motion mechanism (not shown) corresponding to the pair of guide rails 3a and 3b is attached. The linear movement mechanism of the stage 4 is, for example, a screw type linear movement mechanism including a screw shaft (drive shaft) extending in the Y direction along the guide rails 3a and 3b and a ball nut screwed to the screw shaft. The drive shaft is connected to a Y-axis motor (not shown) that receives a predetermined pulse signal and rotates forward and backward in units of steps. When a drive signal corresponding to a predetermined number of steps is input to the Y-axis motor, the Y-axis motor rotates normally or reversely, and the stage 4 corresponds to the same number of steps along the Y-axis direction. The robot moves forward or backward (scans in the Y direction) at a predetermined speed.

  Further, a main scanning position detection device 5 is disposed on the upper surface 2a of the base 2 in parallel with the guide rails 3a and 3b so that the position of the stage 4 can be measured.

  In the base 2, vent holes 6 are formed between the guide rail 3 a and the main scanning position detection device 5 and between the guide rail 3 b and the main scanning position detection device 5. And the air of the upper part of the droplet discharge apparatus 1 passes the ventilation hole 6, and flows in the direction of a floor (downward direction in the figure).

  A placement surface 7 is formed on the upper surface of the stage 4, and a suction-type substrate chuck mechanism (not shown) is provided on the placement surface 7. When a substrate 8 as a workpiece is placed on the placement surface 7, the substrate 8 is positioned and fixed at a predetermined position on the placement surface 7 by a substrate chuck mechanism.

  A pair of support bases 9a and 9b are erected on both sides in the X direction of the base 2, and a guide member 10 extending in the X direction is installed on the pair of support bases 9a and 9b.

  On the upper side of the guide member 10, a storage tank 11 for storing the functional liquid to be discharged is provided. On the other hand, a guide rail 12 extending in the X direction is provided on the lower side of the guide member 10 so as to protrude over the entire width in the X direction.

  A carriage 13 as a table that is movably arranged along the guide rail 12 is formed in a substantially rectangular parallelepiped shape. The linear movement mechanism of the carriage 13 is, for example, a screw type linear movement mechanism including a screw shaft (drive shaft) extending in the X direction along the guide rail 12 and a ball nut screwed with the screw shaft. The drive shaft is connected to an X-axis motor (not shown) that receives a predetermined pulse signal and rotates forward and backward in steps. When a drive signal corresponding to a predetermined number of steps is input to the X-axis motor, the X-axis motor rotates forward or backward, and the carriage 13 moves forward or backward along the X direction by the amount corresponding to the same number of steps. Move (scan in X direction). A sub-scanning position detector 14 is arranged between the guide member 10 and the carriage 13 so that the position of the carriage 13 can be measured. A droplet discharge head 15 is provided on the lower surface of the carriage 13 (the surface on the stage 4 side).

  A cleaning unit 16 is disposed on the upper side of the base 2 and on one side (right side in the drawing) of the stage 4. The cleaning unit 16 includes a maintenance stage 17, a flushing unit 18 serving as a preliminary discharge region, a capping unit 19, a wiping unit 20, a weight measuring device 21 serving as a discharge amount measuring unit, and the like disposed on the maintenance stage 17. It is configured.

  The maintenance stage 17 is located on the guide rails 3 a and 3 b and includes a linear motion mechanism similar to that of the stage 4. By detecting the position using the main scanning position detection device 5 and moving with a linear motion mechanism, it is possible to move to a desired location and stop.

  The flushing unit 18 is a device that receives liquid droplets ejected from the liquid droplet ejection head 15 when the flow path in the liquid droplet ejection head 15 is washed. When solid matter is mixed in the droplet discharge head 15, in order to exclude the solid matter from the droplet discharge head 15, droplets are discharged from the droplet discharge head 15 for cleaning. The flushing unit 18 performs the function of receiving the droplets.

  The capping unit 19 is a device that covers the droplet discharge head 15. Droplets discharged from the droplet discharge head 15 may have volatility, and when the functional liquid solvent contained in the droplet discharge head 15 volatilizes from the nozzle, the viscosity of the functional liquid changes and the nozzle is clogged. Sometimes. The capping unit 19 covers the droplet discharge head 15 to prevent the nozzles from being clogged.

  The wiping unit 20 is a device that wipes the nozzle plate on which the nozzles of the droplet discharge head 15 are arranged. The nozzle plate is a member disposed on the surface of the droplet discharge head 15 that faces the substrate 8. When droplets adhere to the nozzle plate, the droplets adhering to the nozzle plate may come into contact with the substrate 8, and the droplets may adhere to an unplanned location on the substrate 8. The wiping unit 20 prevents droplets from adhering to unscheduled locations on the substrate 8 by wiping the nozzle plate.

  The weight measuring device 21 is provided with an electronic balance, and a tray is arranged on the electronic balance. A droplet is ejected from the droplet ejection head 15 to a tray, and an electronic balance measures the weight of the droplet. The tray is provided with a sponge-like absorber so that the ejected liquid droplets bounce and do not come out of the tray. The electronic balance measures the weight of the tray before and after the droplet discharge head 15 discharges droplets. The difference between the weights of the trays before and after the discharge is calculated, and the weight of the droplets to be discharged is measured.

  As the maintenance stage 17 moves along the guide rails 3 a and 3 b, any one of the flushing unit 18, the capping unit 19, the wiping unit 20, and the weight measuring device 21 is disposed at a location facing the droplet discharge head 15. The device is arranged.

  When the carriage 13 moves along the guide rail 12 in the X direction, the droplet discharge head 15 moves to a position facing the cleaning unit 16 or the substrate 8 and discharges droplets. ing.

  The droplet discharge device 1 includes support columns 22 at four corners, and an air control device 23 at the top (upper side in the figure). The air control device 23 includes a fan, a filter, a cooling / heating device, a humidity adjusting device, and the like. The fan (blower) takes in the air in the factory, passes through the filter, removes dust and dirt in the air, and supplies purified air.

  The air conditioner is a device that controls the temperature of the supplied air so that the atmospheric temperature of the droplet discharge device 1 is maintained within a predetermined temperature range. The humidity adjusting device is a device that controls the humidity of air supplied by dehumidifying or humidifying air so that the atmospheric humidity of the droplet discharge device 1 is maintained within a predetermined humidity range.

  A sheet 24 is disposed between the four support columns 22 to block the air flow. The air supplied from the air control device 23 flows from the air control device 23 toward the floor 25 (in the direction from the top to the bottom in the figure), and dust and dirt in the space surrounded by the sheet 24 are directed toward the floor 25. To flow. As a result, dust and dirt are less likely to adhere to the substrate 8.

  FIG. 2A is a schematic plan view of the droplet discharge head 15. As shown in FIG. 2A, a droplet discharge head 15 is disposed on the carriage 13, and a nozzle plate 30 is disposed on the surface of the droplet discharge head 15. A plurality of nozzles 31 are arranged on the nozzle plate 30. The number of nozzles 31 may be set according to the pattern to be ejected and the size of the substrate 8. In the present embodiment, for example, the number is set to 30.

  Of the nozzles 31 arranged in the droplet discharge head 15, the leftmost nozzle 31 in the drawing is referred to as nozzles 31 a, 31 b, 31 c, and 31 d in order from the left. In the figure, the nozzle 31 at the center is the nozzles 31e, 31f, and 31g in order from the left, and the nozzle 31 at the right end in the figure is the nozzles 31h, 31i, 31j, and 31k in order from the left. The nozzles 31 a to 31 k are all nozzles 31.

  FIG. 2B is a schematic cross-sectional view of a main part for explaining the structure of the droplet discharge head 15. As shown in FIG. 2B, the droplet discharge head 15 includes a nozzle plate 30, and a nozzle 31 is formed on the nozzle plate 30. A cavity 32 communicating with the nozzle 31 is formed at a position above the nozzle plate 30 and facing the nozzle 31. The functional liquid 33 stored in the storage tank 11 is supplied to the cavity 32 of the droplet discharge head 15.

  Above the cavity 32, a vibration plate 34 that vibrates in the vertical direction (Z direction) and expands and contracts the volume in the cavity 32 and a piezoelectric element 35 that expands and contracts in the vertical direction to vibrate the vibration plate 34 are arranged. Has been. The piezoelectric element 35 expands and contracts in the vertical direction to pressurize and vibrate the vibration plate 34, and the vibration plate 34 expands and contracts the volume in the cavity 32 to pressurize the cavity 32. Thereby, the pressure in the cavity 32 fluctuates, and the functional liquid 33 supplied into the cavity 32 is discharged through the nozzle 31.

  When the droplet discharge head 15 receives a nozzle drive signal for controlling and driving the piezoelectric element 35, the piezoelectric element 35 expands and the diaphragm 34 reduces the volume in the cavity 32. As a result, the functional liquid 33 corresponding to the reduced volume is discharged as droplets 36 from the nozzles 31 of the droplet discharge head 15. When the droplets 36 are ejected from the nozzles 31, a part of the energy applied to the droplet ejection head 15 is converted into heat in order to eject the droplets 36. And the periphery of the nozzle 31 which discharges the droplet 36 is heated, and temperature rises.

  The droplet discharge head 15 may discharge the droplets 36 from all the nozzles 31, but may not discharge the droplets 36 from some of the nozzles 31. The location where each nozzle 31 discharges is designed according to the pattern shape to be drawn. At this time, when it is easier to design a place where each nozzle 31 discharges than when discharging using all the nozzles 31, a part of the nozzles 31 is used. It discharges using the nozzle 31. FIG. For example, in the present embodiment, the droplets 36 are not ejected from the nozzles 31a, 31b, 31j, and 31k located on both ends. For other reasons, some nozzles 31 may be used for ejection.

  FIG. 3 is an electric control block diagram of the droplet discharge device. In FIG. 3, the droplet discharge device 1 includes a CPU (arithmetic processing unit) 40 that performs various arithmetic processes as a processor, and a memory 41 that stores various types of information.

  The main scanning drive device 42, the sub-scanning drive device 43, the main scanning position detection device 5, the sub-scanning position detection device 14, and the head drive circuit 44 that drives the droplet discharge head 15 include an input / output interface (I / F) 45 and It is connected to the CPU 40 via the data bus 46. Further, an input device 47, a display device 48, an electronic balance 49, a flushing unit 18, a capping unit 19, and a wiping unit 20 constituting the weight measuring device 21 shown in FIG. 1 are also provided with an input / output interface (I / F) 45 and a data bus 46. It is connected to the CPU 40 via Similarly, in the cleaning unit 16, a cleaning selection device 50 that selects one unit is also connected to the CPU 40 via an input / output interface (I / F) 45 and a data bus 46.

  The main scanning drive device 42 is a device that controls the movement of the stage 4, and the sub-scanning drive device 43 is a device that controls the movement of the carriage 13. The main scanning position detection device 5 recognizes the position of the stage 4 and the main scanning driving device 42 controls the movement of the stage 4 so that the stage 4 can be moved and stopped to a desired position. Yes. Similarly, the sub-scanning position detecting device 14 recognizes the position of the carriage 13 and the sub-scanning driving device 43 controls the movement of the carriage 13 so that the carriage 13 can be moved to and stopped at a desired position. It has become.

  The input device 47 is a device that inputs various processing conditions for discharging the droplets 36. For example, the input device 47 is a device that receives and inputs coordinates for discharging the droplets 36 on the substrate 8 from an external device (not shown). The display device 48 is a device that displays processing conditions and work status, and an operator performs an operation using the input device 47 based on information displayed on the display device 48.

  The electronic balance 49 is a device that measures the weight of the droplets 36 ejected by the droplet ejection head 15 and the tray that receives the droplets 36. The weight of the saucer before and after the droplet 36 is discharged is measured, and the measured value is transmitted to the CPU 40. The weight measuring device 21 shown in FIG. 1 includes a tray and an electronic balance 49.

  The cleaning selection device 50 selects one device from the flushing unit 18, the capping unit 19, the wiping unit 20, and the weight measuring device 21, and sets the maintenance stage 17 so as to be positioned at a location facing the droplet discharge head 15. It is a moving device.

  The memory 41 is a concept including a semiconductor memory such as a RAM and a ROM, and an external storage device such as a hard disk and a CD-ROM. Functionally, a storage area is set for storing program software 51 in which a procedure for controlling operations in the droplet discharge device 1 is described. Further, a storage area for storing the discharge position data 52 which is the coordinate data of the discharge position in the substrate 8 is also set. In addition, in the warm-up driving of the droplet discharge head 15, the warm-up drive data 53 such as the location of the nozzle 31 to be discharged and the discharge frequency data is set. Further, a storage area for storing a main scanning movement amount for moving the substrate 8 in the main scanning direction (Y direction) and a sub scanning movement amount for moving the carriage 13 in the sub scanning direction (X direction); A storage area that functions as a work area, a temporary file, and the like, and various other storage areas are set.

  The CPU 40 performs control for discharging the functional liquid droplets 36 to predetermined positions on the surface of the substrate 8 according to the program software 51 stored in the memory 41. As a specific function realization part, it has the weight measurement calculating part 54 which performs the calculation for implement | achieving the weight measurement using the electronic balance 49. FIG. Furthermore, when the droplet discharge head 15 is warmed up, the cleaning calculation unit 55 that calculates the timing for cleaning the droplet discharge head 15 is selected. And a warm-up discharge calculation unit 56. In addition, a discharge calculation unit 57 that performs calculation for discharging the droplets 36 by the droplet discharge head 15 is provided.

  If the discharge calculation unit 57 is divided in detail, it has a discharge start position calculation unit 58 for setting the droplet discharge head 15 to an initial position for droplet discharge. Further, the ejection calculation unit 57 includes a main scanning control calculation unit 59 that calculates control for moving the substrate 8 in the main scanning direction (Y direction) at a predetermined speed. In addition, the discharge calculation unit 57 includes a sub-scanning control calculation unit 60 that calculates control for moving the droplet discharge head 15 in the sub-scanning direction (X direction) by a predetermined sub-scanning amount. Further, the discharge calculation unit 57 includes various types such as a nozzle discharge control calculation unit 61 that performs calculation for controlling which nozzle among a plurality of nozzles in the droplet discharge head 15 is operated to discharge the functional liquid. It has a function calculation unit.

(Discharge method)
Next, an ejection method for drawing on the substrate 8 using the above-described droplet ejection apparatus 1 will be described with reference to FIGS. FIG. 4 is a flowchart showing a manufacturing process for measuring the number of ejections required for warming up the droplet ejection head, and FIG. 5 is a flowchart showing a manufacturing process for drawing on a substrate. 6 and 7 are diagrams for explaining a discharge method using a droplet discharge device.

  The steps of the manufacturing process for measuring the number of ejections necessary for warming up the droplet ejection head will be described using the flowchart of FIG. Step S1 corresponds to a nozzle temperature measurement step, and is a step of measuring the temperature in the vicinity of each nozzle (hereinafter referred to as nozzle temperature). Next, the process proceeds to step S2. Step S2 corresponds to a temperature determination step for determining whether the variation range of the nozzle temperature is equal to or less than the threshold value, and compares the variation range of the nozzle temperature measured in step S1 with the threshold value to determine whether the variation range of the nozzle temperature is small. It is a process to do. When the fluctuation range of the nozzle temperature is larger than the threshold value (NO), the process proceeds to step S3. In step S2, when the fluctuation range of the nozzle temperature is equal to or less than the threshold (YES), the process proceeds to step S4.

  Step S3 corresponds to a warm-up discharge process, and is a process of discharging droplets from the nozzle. Next, the process proceeds to step S1. If step S1 to step S3 are not performed a plurality of times, data indicating the fluctuation range of the nozzle temperature cannot be obtained in step S2. Therefore, steps S1 to S3 are repeated a predetermined number of times. In the present embodiment, the predetermined number of times is, for example, 10 times. Meanwhile, in step S2, no determination is made, and after step S2, the process proceeds to step S3. Step S4 corresponds to a discharge number setting step, and is a step of storing the number of discharges discharged in step S3 in the warm-up drive data of the memory. Step S1 to step S4 are collectively referred to as step S5. Step S5 corresponds to a preliminary measurement step, and is a step of measuring the number of discharges during which warm-up discharge is performed and the fluctuation range of the nozzle temperature is smaller than a threshold value. This completes the manufacturing process for measuring the number of ejections required for warming up the droplet ejection head.

  Next, steps of the manufacturing process corresponding to the ejection method for drawing on the substrate will be described using the flowchart of FIG. In FIG. 5, steps S6 to S11 are steps for manufacturing with the same droplet discharge device. Step S6 corresponds to a preliminary discharge step, and is a step of discharging the droplets from the nozzles to the receiving tray of the electronic balance and driving the droplet discharge head to warm up. Next, the process proceeds to step S7. Step S7 corresponds to the first measurement process step, and is a step of measuring the weight of the tray of the electronic balance. Next, the process proceeds to step S8. Step S8 corresponds to a measurement discharge step, and is a step of discharging a predetermined number of times from the nozzle to the tray of the electronic balance. Next, the process proceeds to step S9. Step S9 corresponds to the second measurement step, and measures the weight of the tray of the electronic balance. And it is the process of estimating the discharge amount per time using the weight of the saucer measured in Step 7 and the number of discharges discharged in Step S8. A measurement process is comprised from step S7 and step S8. Next, the process proceeds to step S10. Step S10 corresponds to a discharge amount adjustment step, and is a step of adjusting the discharge amount per time. Next, the process proceeds to step S11. Step S11 corresponds to a drawing process as a discharging process, and is a process of drawing by discharging droplets onto the substrate. This completes the manufacturing process of drawing on the substrate.

Next, a manufacturing method for measuring the number of ejections necessary for warming up the droplet ejection head will be described in detail with reference to FIG. 6 in association with the steps shown in FIG.
FIG. 6A and FIG. 6B are diagrams corresponding to step S1 to step S4. As shown in FIG. 6A, the nozzle temperature is measured using the infrared radiation thermometer 62 in step S1. Next to the electronic balance 49, an infrared camera 63 having an area sensor is arranged, and the infrared camera 63 can image the arranged nozzles 31. A temperature analyzer 64 is electrically connected to the infrared camera 63, and an infrared radiation thermometer 62 is configured by the infrared camera 63 and the temperature analyzer 64. The infrared camera 63 receives the infrared light emitted from the nozzle plate 30, converts it into an electrical signal, and outputs it to the temperature analyzer 64. The temperature analyzer 64 converts light energy received by the infrared camera 63 into temperature. Therefore, the temperature around each nozzle 31 on the nozzle plate 30 can be measured as the nozzle temperature.

  Subsequently, in step S2, the fluctuation range of the nozzle temperature is compared with a threshold value. However, initially, since the group of nozzle temperature data is small, step S1 and step S3 are repeated about 10 times. Then, step S2 is performed after step S1.

  In step S <b> 3, the liquid droplet 36 is discharged from the nozzle 31 toward the electronic balance 49. A tray 65 as a preliminary discharge area is arranged on the electronic balance 49, and a sponge-like receiver 66 is stored in the tray 65. When the liquid droplet 36 ejected from the nozzle 31 lands on the receiver 66, the liquid droplet 36 is absorbed by the receiver 66 so that a part of the liquid droplet 36 does not jump out of the tray 65. . Further, when the liquid droplet 36 contains a volatile liquid, the liquid droplet 36 permeates into the receiver 66, so that the liquid droplet 36 is less likely to come into contact with the outside air and is less likely to volatilize. The number of discharges discharged in one step is preferably set in consideration of the responsiveness of the infrared radiation thermometer 62. In the present embodiment, for example, 10 times are adopted. Therefore, when step S1 and step S3 are repeated 10 times, the nozzle 31 discharges 100 times.

  FIG. 6B is a schematic diagram showing the relationship between the number of ejections and the nozzle temperature when ejecting continuously. In the figure, the horizontal axis indicates the number of discharges 67 that one nozzle 31 discharges, and the vertical axis indicates the nozzle temperature 68. A transition of the nozzle temperature 68 with respect to the number of discharges 67 when the droplets 36 are continuously discharged from the nozzle 31 is shown in a nozzle temperature curve 69. In the nozzle temperature curve 69, the nozzle temperature curve 69 at the discharge start point 69a when starting discharge increases as the number of discharges 67 increases. In the temperature rise region 69b, the nozzle temperature 68 rises as the number of discharges 67 increases.

  And even if the number of discharges 67 increases, the temperature equilibrium region 69d where the nozzle temperature 68 does not rise is obtained. In the temperature equilibrium region 69d, in the vicinity of the nozzle 31, the thermal energy radiated by the droplet ejection head 15 and the thermal energy generated by ejection are in an equilibrium state. When the nozzle temperature 68 rises, the temperature difference between the nozzle temperature 68 and the gas surrounding the droplet discharge head 15 (hereinafter referred to as ambient gas) increases. The greater the difference between the nozzle temperature 68 and the ambient gas temperature, the greater the heat energy dissipated from the droplet discharge head 15. Therefore, the nozzle temperature 68 does not increase and stabilizes at a certain nozzle temperature 68. This temperature is set as an equilibrium nozzle temperature 70 as a drawing nozzle temperature.

  The point of transition from the temperature rise region 69b to the temperature equilibrium region 69d is defined as a temperature equilibrium point 69c. In step S2, the temperature equilibrium point 69c at which the variation in the nozzle temperature 68 becomes small is detected by comparing the variation in the nozzle temperature 68 with a threshold value. In step S <b> 4, an equilibrium discharge count 71 as the warm-up discharge count that is the discharge count 67 at the temperature equilibrium point 69 c is stored in the warm-up drive data 53.

Next, a manufacturing method corresponding to the ejection method for drawing on the substrate will be described in detail with reference to FIG. 7 in association with the steps shown in FIG.
FIGS. 7A and 7B are diagrams corresponding to steps S6 to S9. As shown in FIG. 7A, during step S <b> 6 to step S <b> 9, the droplet 36 is discharged from the nozzle 31 to the tray 65 of the electronic balance 49. At this time, the droplets 36 are not discharged from the nozzles 31a, 31b, 31j, and 31k located at both ends of the arranged nozzles 31.

  Since the electronic balance 49 is disposed under the tray 65, the electronic balance 49 can measure the weight of the weight of the tray 65 and the weight of the liquid droplets 36 to be discharged. .

  FIG.7 (b) is a schematic diagram which shows the relationship between the frequency | count of discharge when discharging continuously, and the weight of a saucer. In the figure, the horizontal axis indicates the number of discharges 72 that the nozzle 31 discharges, and the vertical axis indicates the tray weight 73. The tray weight 73 indicates a weight obtained by adding the weight of the tray 65 and the weight of the droplets 36 discharged to the tray 65 and is a weight measured by the electronic balance 49. A transition of the saucer weight 73 with respect to the number of ejections 72 when the droplets 36 are continuously ejected from the nozzle 31 is shown as a saucer weight curve 74.

  In step S6, preliminary discharge is started. Preliminary discharge is discharge for warm-up driving that raises the nozzle temperature 68 of the droplet discharge head 15. In the tray weight curve 74, a place where the discharge is started is set as a discharge start point 74a. In this step, a preset number of preliminary discharges 75 is discharged. The preliminary discharge number 75 is set to discharge with a discharge number equal to or greater than the equilibrium discharge number 71 shown in FIG. Therefore, when this step is completed, the nozzle temperature 68 becomes the equilibrium nozzle temperature 70.

  Subsequently, in step S <b> 7, the weight of the tray 65 is measured, and this weight is set as a first weight 76. The CPU 40 stores the first weight 76 in the memory 41. The first weight 76 includes weights such as the weight of the tray 65 itself and the weight of the ejected droplets 36. In the saucer weight curve 74, the location of this step is defined as a first measurement point 74b.

  Next, in step S8, a predetermined number of ejections are performed. This number of times is set as the measured discharge number 77. The measurement discharge number 77 may be any number that allows the average weight of the discharged droplets 36 to be statistically measured. In the present embodiment, for example, the nozzles 31a, 31b, 31j, and 31k located at both ends are excluded. From each nozzle 31, discharge is performed 100 times.

  In this step, discharge is performed in a state where the nozzle temperature 68 is stable at the equilibrium nozzle temperature 70. When the nozzle temperature 68 is stabilized, the variation in the weight of the ejected droplets 36 is reduced. Therefore, in this step, the tray weight curve 74 is substantially straight.

  Subsequently, in step S <b> 9, the weight of the tray 65 is measured, and this weight is set as a second weight 78. The CPU 40 stores the second weight 78 in the memory 41. In addition to the first weight 76, the second weight 78 includes the weight of the droplets 36 discharged to the tray 65 in step S8. In the saucer weight curve 74, the location of this step is defined as a second measurement point 74c.

  The number of discharges discharged between the first measurement point 74 b and the second measurement point 74 c is the measured discharge number 77. The total weight of the discharged liquid droplet 36 between the first measurement point 74b and the second measurement point 74c is a value obtained by subtracting the first weight 76 from the second weight 78, and this value is measured and discharged. The liquid weight is 79. At this time, the average discharge weight in one discharge can be obtained by dividing the measured discharge liquid weight 79 by the measured discharge frequency 77. The average discharge amount per nozzle, which is the weight of the droplets 36 discharged from one nozzle 31, can be obtained by dividing the average discharge weight by the number of discharged nozzles 31. The weight measurement calculation unit 54 acquires the measured discharge number 77, the first weight 76, and the second weight 78 from the memory 41, and calculates the average discharge amount per nozzle.

  In step S10, the weight of the ejected droplets 36 is adjusted. When the head drive circuit 44 drives the droplet discharge head 15, the drive voltage waveform is applied to the piezoelectric element 35 to drive it. At this time, the larger the drive voltage that is the voltage difference between the maximum voltage and the minimum voltage of the drive voltage waveform, the greater the weight of the ejected droplets 36 than when the drive voltage is small. Further, the memory 41 stores data of a voltage ejection amount correlation table, which is a relationship between the increment of the driving voltage and the increment of the weight of the droplet 36 to be ejected.

  First, the nozzle discharge control calculation unit 61 compares the target discharge amount, which is the discharge amount of the droplets 36 to be adjusted, with the average discharge amount per nozzle. When the average discharge amount is larger than the target discharge amount, the drive voltage is decreased. When the average discharge amount is smaller than the target weight, the drive voltage is increased. The nozzle discharge control calculation unit 61 calculates a voltage when adjusting the drive voltage with reference to the voltage discharge amount correlation table. Then, the calculated drive voltage is stored in the memory 41.

  FIG. 7C is a diagram corresponding to step S11. As shown in FIG. 7C, the droplet discharge device 1 relatively moves the stage 4 and the carriage 13. Then, the droplet discharge head 15 is moved to a location on the substrate 8 opposite to the location where the functional liquid 33 is applied. Next, the liquid droplets 36 are ejected from the nozzle 31 for drawing.

  At this time, the nozzle ejection control computation unit 61 computes in step S10 and applies the drive voltage waveform of the drive voltage stored in the memory 41 to the piezoelectric element 35 for ejection. When discharging from the nozzle 31 to the substrate 8, the droplets 36 are discharged at a high frequency from the nozzle 31, so that the drawing nozzle temperature which is the nozzle temperature 68 at the time of drawing is substantially the same as the equilibrium nozzle temperature 70. Therefore, in the drawing process, it is possible to draw by discharging the target discharge amount of the liquid droplets 36. When the drawing on the substrate 8 is completed, the drawing manufacturing process is completed.

As described above, this embodiment has the following effects.
(1) According to the present embodiment, in step S <b> 6, the liquid droplets 36 are received from the nozzle 31 and discharged to the tray 65, and the nozzle 31 is heated. At this time, the liquid droplets 36 are discharged until the equilibrium nozzle temperature 70 which is the nozzle temperature 68 which is substantially the same as the drawing nozzle temperature which is the nozzle temperature 68 in step S11. In step S <b> 8, the droplet 36 is received from the nozzle 31 and discharged to the tray 65. In step S7 and step S9, the electronic balance 49 measures the weight of the droplet 36 discharged from the nozzle 31. In step S <b> 10, the droplets 36 to be ejected are adjusted. In step S <b> 11, the droplets 36 are ejected from the nozzle 31 to the substrate 8.

  Since the viscosity of the functional liquid 33 changes as the temperature changes, pressure is applied to the functional liquid 33 in the droplet discharge head 15, and the fluid resistance changes when passing through the flow path such as the nozzle 31. The discharge amount of the droplets 36 discharged from the nozzle changes.

  In step S6, the nozzle 31 is heated to an equilibrium nozzle temperature 70 that is substantially the same as the drawing nozzle temperature. In step S <b> 8, the droplets 36 are ejected from the nozzle 31 having the equilibrium nozzle temperature 70. Therefore, in step S7 and step S9, the discharge amount at the nozzle 31 at the equilibrium nozzle temperature 70 can be measured. As a result, the discharge amount can be accurately measured and drawn.

  (2) According to the present embodiment, in step S9, the average discharge amount per nozzle in the droplets 36 discharged from the nozzle 31 is accurately measured. In step S10, the discharge amount of the droplets 36 discharged from the nozzle 31 is adjusted based on the measured average discharge amount per nozzle. Since the adjustment is performed based on the average discharge amount per nozzle measured with high accuracy, the discharge amount can be controlled with high accuracy for drawing.

  (3) According to the present embodiment, in step 5, the number of ejections from the nozzle temperature 68 when the nozzle 31 ejects the liquid droplet 36 and does not eject from the nozzle 31 for a long time until the equilibrium nozzle temperature 70 is reached. A certain number of equilibrium discharges 71 is measured. Then, a preliminary discharge number 75 is set from the equilibrium discharge number 71. In step S <b> 6, the liquid droplet 36 having the preliminary discharge count of 75 is discharged. Therefore, even when the nozzle temperature 68 is the nozzle temperature 68 when the ejection is not performed for a long time, the equilibrium nozzle temperature 70 can be set in step S6.

  (4) According to the present embodiment, the droplet discharge head 15 includes the plurality of nozzles 31. In step S6, the droplet 36 is discharged from the nozzle 31 that discharges the droplet 36 in step S11. That is, in step S11, the droplets 36 are not ejected from the nozzles 31a, 31b, 31j, and 31k among all the nozzles 31 included in the droplet ejection head 15. At this time, even in step S6, the droplets 36 are not discharged from the nozzles 31a, 31b, 31j, and 31k among all the nozzles 31.

  Since it is not necessary to measure the discharge amount of the nozzle 31 that does not discharge the droplets 36 in step S11, it is not necessary to heat the nozzle 31 in step S6. Compared to the case where the liquid droplets 36 are discharged from all the nozzles 31 in step S6, it is not necessary to discharge from the nozzles 31 that do not need to discharge the liquid droplets 36. It can be a method.

(Second Embodiment)
Next, an embodiment of a discharge method embodying the present invention will be described with reference to FIGS. 2, 4 to 5 and 8.
This embodiment differs from the first embodiment in that the drive waveform for driving the piezoelectric element of the droplet discharge head is different.

  That is, in the first embodiment, driving is performed by applying, to the piezoelectric element 35, a driving waveform for ejecting the droplets 36 continuously from the nozzle 31 in step S3 shown in FIG. 4, step S6 and step S8 shown in FIG. Was.

  In this embodiment, when drawing on the substrate 8 in step S11, a pattern equivalent to the pattern of the drive waveform applied to the piezoelectric element 35 is used, and in step S3, step S6 and step S8, the piezoelectric element 35 is moved. Driven to discharge the droplet 36 from the nozzle 31.

  FIG. 8 is a diagram illustrating a drive waveform pattern for driving the piezoelectric element. FIG. 8A is a diagram showing a part of a drive waveform pattern for driving the piezoelectric element 35 when the droplet 36 is ejected from the nozzle 31d shown on the left side of FIG. Similarly, FIG. 8B is a diagram showing a part of a drive waveform pattern for driving the piezoelectric element 35 when the liquid droplet 36 is ejected from the nozzle 31f shown in the center of FIG. FIG. 8C is a diagram showing a part of a drive waveform pattern for driving the piezoelectric element 35 when the droplet 36 is ejected from the nozzle 31i shown on the right side of FIG.

  8A, 8B, and 8C, a drawing waveform that is a pattern of a driving waveform applied to the piezoelectric element 35 when drawing on the substrate 8 in step S11 shown in FIG. Indicates a pattern. In FIG. 8A, FIG. 8B, and FIG. 8C, the horizontal axis indicates the passage of time 82, and the vertical axis indicates the drive voltage 83. As shown in FIGS. 8A, 8B, and 8C, the drive waveform pattern 84 has a place where the drive voltage is applied at equal intervals and a place where the drive voltage is not applied. In the drawing section 85, a pulse 84a is formed in accordance with the pattern to be drawn. Therefore, the presence or absence of the pulse 84a is designed by the pattern to be drawn. Since the nozzles 31d, 31f, and 31i pass through different places, the drive waveform patterns 84 are different from each other.

  The droplet 36 is discharged at a place where the pulse 84a is formed, and the discharge is stopped at a place where the pulse 84a is not formed. Accordingly, the drive waveform pattern 84 has the same form as the discharge pattern for discharging the droplets 36 from the nozzles 31 and stopping the discharge.

  The drawing stop section 86 is a section where the pulse 84a is not formed. In this section, the place facing the nozzle 31 is a place away from the place where the nozzle 8 is discharged, and the discharge is stopped. Then, when the stage 4 is moved by changing the traveling direction of the stage 4 and the place facing the nozzle 31 is the place to be ejected to the substrate 8, the ejection is resumed to become the drawing section 85.

  In step S3, when warm-up discharge is performed, droplets 36 are discharged using the waveform pattern during drawing. Then, the number of equilibrium discharges 71 is measured. In step S4, the number of preliminary discharges 75 is set with reference to the balanced discharge number 71. Accordingly, the preliminary ejection number 75 is the number of ejections when the droplets 36 are ejected using the waveform pattern at the time of drawing.

  In step S6, ejection is performed for the preliminary ejection number 75 using the waveform pattern at the time of drawing. At this time, the nozzle temperature 68 is substantially equal to the equilibrium nozzle temperature 70. In step S8, measurement discharge is performed using the waveform pattern during drawing. Accordingly, in step S9, the average discharge amount per nozzle when using the waveform pattern during drawing can be calculated. In step S10, the discharge amount is adjusted using the average discharge amount per nozzle, and in step S11, the droplets 36 are discharged and drawn using the drive waveform pattern of the adjusted drive voltage.

As described above, according to the present embodiment, in addition to the effects (1) to (3) of the first embodiment, the following effects are obtained.
(1) According to the present embodiment, in step S6 and step S8, when the droplet 36 is ejected from the nozzle 31, the waveform pattern at the time of drawing is used as the drive pattern for driving the piezoelectric element 35.

  In step S6, step S8, and step S11, the droplet discharge heads 15 have substantially the same temperature distribution because they are discharged with substantially the same discharge pattern. Accordingly, in step S8, the droplet 36 is discharged from the nozzle 31 in the droplet discharge head 15 having substantially the same temperature distribution as in step S11. In step S7 and step S9, the discharge amount in the droplet discharge head 15 having the same temperature distribution as in step S11 can be measured. As a result, it is possible to accurately measure the discharge amount in the drawing process of step S11.

(Third embodiment)
Next, an embodiment of a discharge method embodying the present invention will be described with reference to FIGS. 2, 4 to 5, and FIGS. 9 to 10.
This embodiment differs from the second embodiment in that the piezoelectric element 13 is driven using a warm-up drive waveform pattern instead of the drawing waveform pattern.

  In other words, in the second embodiment, when drawing is performed, the preliminary discharge and the measurement discharge are performed using a drawing waveform pattern that is a drive waveform pattern for driving the piezoelectric element 35. In the present embodiment, the warm-up drive waveform pattern is formed with reference to the drawing waveform pattern, and preliminary discharge and measurement discharge are performed.

  FIG. 9 is a flowchart of a manufacturing process for forming a warm-up drive waveform pattern. The steps of the manufacturing process for forming the warm-up drive waveform pattern will be described using the flowchart of FIG. First, step S12 corresponds to a discharge count counting process for each nozzle, and is a process of counting the discharge count at each nozzle. Next, the process proceeds to step S13. Step S13 corresponds to a discharge time calculation step, and is a step of calculating the discharge time required for drawing. Next, the process proceeds to step S14. Step S14 corresponds to a discharge frequency calculation step for each nozzle, and is a step of calculating the number of discharges per unit time. Next, the process proceeds to step S15. Step S15 corresponds to a discharge pattern setting step and is a step of forming a warm-up drive waveform pattern. Steps S12 to S15 are collectively referred to as step S16. Step S16 corresponds to a preliminary ejection pattern forming step. The warm-up drive waveform pattern is completed through the above steps.

  Next, a manufacturing method for forming a warm-up drive waveform pattern will be described in detail with reference to FIG. 10 in association with the steps shown in FIG. The waveform pattern handles a long pattern. However, in order to simplify the description, the description is limited to the waveform pattern in the figure.

  FIG. 10 is a diagram for explaining a pattern of a driving waveform for driving a piezoelectric element, and FIGS. 10A and 10B show an example of a driving waveform pattern at the time of drawing. 10A and 10B, the horizontal axis indicates the passage of time 82, and the vertical axis indicates the drive voltage 83. In step S12, the number of ejections during drawing is counted. When drawing on the substrate 8, the number of ejections ejected by each nozzle 31 is counted. For example, in the first drawing waveform pattern 87 in FIG. 10A, 40 pulse waveforms are formed, and therefore the number of ejections is 40. Similarly, since 42 pulse waveforms are formed in the second drawing waveform pattern 88 of FIG. 10B, the number of ejections is 42.

  In step S13, the discharge time is calculated. The time required for drawing on the substrate 8 is calculated. For example, in FIG. 10A and FIG. 10B, the first drawing waveform pattern 87 or the second drawing waveform pattern 88 of 50 pulses is drawn. In order to simplify the description, the discharge time is 50 seconds.

  In step S14, the number of discharges per unit time is calculated. Since 40 pulses are formed in the first drawing waveform pattern 87 in 50 seconds, the number of ejections per unit time is 40/50 (pulses / second). This is the same as 0.8 (pulses / second). Similarly, since the second drawing waveform pattern 88 is formed with 42 pulses in 50 seconds, it is set to 42/50 (pulses / second). This is the same as 0.82 (pulses / second).

  In step S15, a warm-up drive waveform pattern is formed from the number of discharges per time calculated in step S14. Since the first drawing waveform pattern 87 is 0.8 (pulses / second), the number of ejections is 4 pulses in 5 seconds. A first warm-up drive waveform pattern 89 shown in FIG. 10C is a waveform formed based on the number of ejections per unit time of the first drawing waveform pattern 87 shown in FIG. Since the first warm-up drive waveform pattern 89 forms four pulses in the time of five pulses, the number of ejections per unit time is 0.8 (pulses / second).

  Similarly, the second drawing waveform pattern 88 is a waveform formed based on the number of ejections per unit time of the second drawing waveform pattern 88 shown in FIG. Since the number of ejections per unit time of the second drawing waveform pattern 88 is 0.82 (pulses / second), the number of ejections is about 5 pulses in 6 seconds. In the second warm-up drive waveform pattern 90 shown in FIG. 10 (d), 5 pulses are formed in the time of 6 pulses, so the number of ejections per unit time is 0.83 (pulses / second). It has become.

  In this manner, in step S15, the number of pulses included in a predetermined time is adjusted to form a warm-up drive waveform pattern that repeats the same pattern. The warm-up drive waveform pattern is a drive waveform pattern that drives the piezoelectric element 35 during warm-up driving. Using this warm-up drive waveform pattern, the piezoelectric element 35 is driven, and the droplets 36 are ejected from the nozzle 31.

  The droplet 36 is ejected at the place where the pulses 89a and 90a are formed, and the ejection is stopped at the place where the pulses 89a and 90a are not formed. Accordingly, the first warm-up drive waveform pattern 89 and the second warm-up drive waveform pattern 90 have the same form as the discharge pattern for discharging the droplets 36 from the nozzle 31 and discharging stop. This discharge pattern is used as a preliminary discharge pattern. In step S6 shown in FIG. 5, preliminary discharge is performed using this preliminary discharge pattern. In step S8, measurement discharge is performed using the preliminary discharge pattern, and the average discharge amount per nozzle is calculated.

As described above, according to the present embodiment, in addition to the effects (1) to (3) of the first embodiment, the following effects are obtained.
(1) According to the present embodiment, this discharge method includes the preliminary discharge pattern forming step of step S16. In the preliminary discharge pattern forming step, a preliminary discharge pattern is formed that has substantially the same ratio as the ratio between the discharge time of the droplets 36 and the discharge stop time in the drawing step. In the preliminary ejection step, ejection is performed using a preliminary ejection pattern.

  Therefore, the temperature distribution of the nozzles 31 in the droplet discharge head 15 is closer to the nozzle temperature 68 at the time of discharge when discharging using the preliminary discharge pattern than when discharging the droplets 36 from all the nozzles. It can be a temperature distribution. As a result, the discharge amount in the droplet discharge head 15 having a temperature distribution close to that at the time of drawing can be measured. As a result, it is possible to accurately measure the discharge amount in the drawing process of step S11.

  (2) According to the present embodiment, in the preliminary discharge pattern forming step in step S <b> 16, the preliminary discharge pattern for performing the discharge corresponding to the equilibrium discharge number 71 is formed. In the drawing process of step S11, when a large number of times of ejection is performed by ejecting the liquid droplets 36, a large number of liquid droplets 36 are ejected in the preliminary ejection when ejecting using the ejection pattern in the rendering process in the preliminary ejection process. Consume. The preliminary ejection pattern can be set so as to eject the number of ejections suitable for the preliminary ejection. Therefore, since the number of discharges required for the preliminary discharge can be set optimally, the preliminary discharge can be performed in a resource-saving manner.

(Fourth embodiment)
Next, an embodiment of a discharge method embodying the present invention will be described with reference to FIGS.
This embodiment differs from the first embodiment in that a temperature sensor is built in the droplet discharge head.

  FIG. 11 is a schematic cross-sectional view of a main part of the droplet discharge head. That is, in the present embodiment, a droplet discharge head 94 is configured as shown in FIG. The droplet discharge head 94 includes a nozzle plate 30. A nozzle 31 is formed on the nozzle plate 30. A cavity 32 communicating with the nozzle 31 is formed at a position above the nozzle plate 30 and facing the nozzle 31. A temperature sensor 95 is formed so as to be in contact with the functional liquid 33 in the nozzle plate 30 and the cavity 32. The temperature sensor 95 only needs to be able to measure the nozzle temperature. In the present embodiment, for example, a thermistor is employed.

  Since the temperature sensor 95 is in contact with the functional liquid 33 in the nozzle plate 30 and the cavity 32, the temperature of the functional liquid 33 in the nozzle plate 30 and the cavity 32 can be detected. Since the nozzle plate 30 and the functional liquid 33 are located in the vicinity of the nozzle 31, the temperature sensor 95 can detect the temperature in the vicinity of the nozzle 31.

  The droplet discharge head 94 includes a plurality of nozzles 31, and one temperature sensor 95 is disposed corresponding to one nozzle 31. The temperature in the vicinity of each nozzle 31 can be detected, and the nozzle temperature distribution in all the arranged nozzles 31 is detected.

  FIG. 12 is an electric control block diagram of the droplet discharge device. The droplet discharge device 96 includes one droplet discharge head 94, and the droplet discharge head 94 includes 30 nozzles 31. One temperature sensor 95 is arranged for each nozzle 31. That is, since 30 nozzles 31 are arranged, 30 temperature sensors 95 are also arranged.

  The temperature sensor 95 is connected to the nozzle temperature detection device 97. The nozzle temperature detecting device 97 is connected to the CPU 40 via an input / output interface (I / F) 45 and a data bus 46. A temperature measurement unit is configured by the temperature sensor 95, the nozzle temperature detection device 97, and the like.

  The temperature sensor 95 outputs a voltage signal corresponding to the temperature near the nozzle 31 to the nozzle temperature detection device 97. The nozzle temperature detection device 97 receives the voltage signal, converts it into a digital signal corresponding to the temperature, and outputs it to the CPU 40. The nozzle temperature detection device 97 receives a voltage signal from a temperature sensor 95 disposed near each nozzle 31. The nozzle temperature detection device 97 outputs a digital signal corresponding to the temperature near each nozzle 31 to the CPU 40. Therefore, the CPU 40 can recognize the nozzle temperature of each nozzle 31.

FIG. 13 is a flowchart showing a manufacturing process in which drawing is performed by preliminary discharge from the droplet discharge head.
In FIG. 13, step S21 corresponds to a nozzle temperature measurement step, and is a step of detecting the nozzle temperature of each nozzle using a nozzle temperature detection device. Next, the process proceeds to step S22. Step S22 corresponds to a temperature determination step, and is a step in which the warm-up discharge calculation unit determines whether there is a nozzle whose nozzle temperature is lower than the warm-up reference value. When there is a nozzle whose nozzle temperature is lower than the warm-up reference value (YES), the process proceeds to step S23. In step S22, when there is no nozzle whose nozzle temperature is lower than the warm-up reference value (NO), the process proceeds to step S24.

  Step S23 corresponds to a warm-up discharge process, and is a process of discharging to a tray of an electronic balance. Next, the process proceeds to step S21. Steps S21 to S23 are collectively referred to as step S30. Step S30 corresponds to a preliminary discharge step, and is a step of performing preliminary discharge until all nozzle temperatures are higher than a set value. Next, the process proceeds to step S24.

  Steps S24 to S28 are the same as steps S7 to S11 shown in FIG.

Next, the manufacturing method will be described in detail with reference to FIG. 12 in association with the steps shown in FIG.
In step S 21, the temperature sensor 95 shown in FIG. 12 detects the nozzle temperature of each droplet discharge head 94, converts it into a voltage signal, and outputs it to the nozzle temperature detection device 97. The nozzle temperature detection device 97 converts a voltage signal indicating the nozzle temperature into a digital signal and outputs the digital signal to the CPU 40. The CPU 40 receives the digital signal indicating the nozzle temperature and recognizes the nozzle temperature of each nozzle 31.

  In step S <b> 22, the warm-up discharge calculation unit 56 reads the warm-up reference value for the nozzle temperature from the warm-up drive data 98. The nozzle temperature warm-up reference value is a value determined in advance by a discharge experiment, and the nozzle temperature for continuous discharge during a predetermined time is set and stored in the warm-up drive data 98. This warm-up reference value corresponds to the equilibrium nozzle temperature 70 in the first embodiment. The warm-up discharge calculation unit 56 compares the nozzle temperature warm-up reference value with the nozzle temperature of each nozzle 31, and extracts the nozzle 31 whose nozzle temperature is lower than the nozzle temperature warm-up reference value.

  In step S <b> 23, the CPU 40 outputs an ejection instruction signal to the head drive circuit 44. At this time, the CPU 40 outputs an instruction signal for discharging from the nozzle 31 extracted in step S22. The head drive circuit 44 inputs an instruction signal and drives the droplet discharge head 94. Then, the droplet discharge head 94 discharges a predetermined number of droplets 36 from the nozzle 31 extracted in step S22. That is, the droplet discharge head 15 discharges a predetermined number of droplets 36 from the nozzle 31 whose nozzle temperature is lower than the reference value of the nozzle temperature.

  In step S30, the temperature of each nozzle 31 rises by repeating step S21 to step S23. And the nozzle temperature of all the nozzles 31 becomes higher than a warm-up reference value. At that time, the process proceeds from step S22 to step S24.

  In step S24 to step S27, the discharge amount is measured and adjusted, and in step S28, the ink is discharged and drawn on the substrate 8. With the above steps, the drawing manufacturing process is completed.

As described above, according to the present embodiment, in addition to the effect (1) of the first embodiment, the following effect is obtained.
(1) According to this embodiment, the nozzle temperature measuring step in step S21, the temperature determining step in step S22, and the warm-up discharge step in step S23 are provided. In the nozzle temperature measuring step, the nozzle temperature of the droplet discharge head 94 is measured. In the temperature determination step, it is determined whether the nozzle temperature measured in the nozzle temperature measurement step has reached a predetermined temperature. In the warm-up discharge process, the droplet 36 is discharged from the nozzle 31 when the nozzle temperature does not reach the predetermined temperature in the temperature determination process. Then, the nozzle temperature measurement process, the temperature determination process, and the warm-up discharge process are repeated so that the nozzle temperature reaches a predetermined temperature.

  The nozzle temperature is measured, and when the nozzle temperature is lower than a predetermined temperature, the droplets 36 are discharged from the nozzle 31 to increase the nozzle temperature. Since this is repeated until the nozzle temperature reaches a predetermined temperature, the nozzle temperature can surely reach the predetermined temperature.

In addition, this invention is not limited to embodiment mentioned above, A various change and improvement can also be added. A modification will be described below.
(Modification 1)
In the first embodiment, the infrared camera 63 is used as the thermometer for measuring the temperature of the nozzle 31, but another thermometer may be used. It is sufficient if the temperature of the nozzle 31 can be detected. In addition, for example, a thermocouple, a platinum resistance temperature detector, a crystal resonator, or the like can be used as the temperature sensor. By using a sensor that is sensitive to the nozzle temperature, the temperature can be detected with high accuracy.

(Modification 2)
In the fourth embodiment, a thermistor is employed as the temperature sensor 95, but it is sufficient if the temperature of the nozzle 31 can be detected. In addition, for example, a thermocouple, a platinum resistance thermometer, a crystal resonator, or the like can be used as the temperature sensor 95. By using a sensor that is sensitive to the temperature of the functional liquid 33, the temperature can be detected with high accuracy.

(Modification 3)
In the first embodiment, the discharge amount is estimated by measuring the weight of the droplet 36 discharged from the nozzle 31. However, the discharge amount may be measured by measuring the volume of the discharge amount. For example, the discharge amount may be estimated by collecting the droplets 36 to be discharged into a tube having a constant cross-sectional area and measuring the volume by measuring the length of the liquid in the tube. In the case of a highly volatile liquid, measurement can be performed in a state where it is difficult to volatilize.

(Modification 4)
In the first embodiment, the tray 65 is set as the preliminary discharge area. However, the present invention is not limited to this, and another place may be set as the preliminary discharge area. For example, a place where the substrate 8 is not disposed on the flushing unit 18 and the base 2, a place where preliminary ejection can be performed on the substrate 8, and the like can be given. In any case, by setting the place where preliminary ejection is easy, a liquid droplet ejection apparatus that is easy to design can be obtained.

(Modification 5)
In the first embodiment, after adjusting the discharge amount in step S10, drawing is performed in step S11. After adjustment in step S10, step S6 to step S10 are repeated, and if it is not necessary to adjust in step S10, the process may move to step S11 and be drawn. By measuring and confirming the adjustment result in step S10 in steps S7 to S9, it is possible to draw with a more accurate discharge amount.

(Modification 6)
In the fourth embodiment, one temperature sensor 76 is arranged corresponding to one nozzle 31 in all the nozzles 31, but one temperature sensor 76 is arranged for a plurality of nozzles 31. Also good. That is, for example, one temperature sensor 76 may be arranged for two nozzles 31. If at least the number of temperature sensors 76 can recognize the temperature distribution, the number of temperature sensors 76 may be reduced with respect to the number of nozzles 31. Since the number of parts is reduced, the droplet discharge device 96 can be manufactured with high productivity.

(Modification 7)
In the first embodiment, the droplets 36 are discharged from the nozzles 31 excluding both ends, and the discharge amount is adjusted. However, the discharge amount may be measured for each nozzle 31 and adjusted. Since the discharge amount is adjusted for each nozzle 31, drawing can be performed with a more accurate discharge amount.

(Modification 8)
In the first to fourth embodiments, the program according to the operation procedure is stored in the memory 41 of the computer, and the droplet discharge devices 1 and 96 are controlled by the program. However, the present invention is not limited to this. Alternatively, control may be performed by a control device configured by an electric circuit. Peripheral devices may be controlled according to the procedure.

(Modification 9)
In the fourth embodiment, the temperature sensor 95 detects the temperature of the nozzle plate 30, but is not limited thereto, and may detect the temperature of the diaphragm 34 and the cavity 32. Further, the temperature of the functional liquid 33 in the cavity 32 may be directly detected. The place where the temperature sensor 95 places the temperature-responsive portion can be placed where the diaphragm 34, the cavity 32, and the functional liquid 33 in the cavity 32 come into contact. It becomes possible to measure. The temperature sensor 95 can be designed to be easily arranged in accordance with the shape of the droplet discharge head 94.

(Modification 10)
In the first to fourth embodiments, the liquid droplets 36 are ejected and drawn on the substrate 8, but an object other than the substrate 8 may be used. For example, it can be applied to drawing of a cylinder, a sphere, a spindle-shaped structure, a rectangular parallelepiped, or the like. In either case, drawing can be performed with a precise discharge amount.

(Modification 11)
In the first embodiment, the operation in a state where the temperature of the nozzle 31 is lower than the temperature of the drawing process in step S11 is described before the preliminary ejection process in step S6. Even before the preliminary discharge process in step S6, the nozzle 31 can be operated in the same operation even when the temperature of the nozzle 31 is higher than the temperature in the drawing process in step S11. When the functional liquid 33 is discharged from the nozzle 31 as droplets 36, the temperature of the nozzle 31 can be close to the temperature of the functional liquid 33 stored in the storage tank 11. Accordingly, even when the temperature of the nozzle 31 is high, the temperature of the nozzle 31 can be brought close to the temperature of the drawing process in step S11 by a similar process.

1 is a schematic perspective view illustrating a configuration of a droplet discharge device according to a first embodiment. (A) is a schematic plan view of a droplet discharge head, and (b) is a schematic cross-sectional view of an essential part for explaining the structure of the droplet discharge head. The electric control block diagram of a droplet discharge device. The flowchart which shows the manufacturing process which measures the frequency | count of discharge required for warming up of a droplet discharge head. The flowchart which shows the manufacturing process drawn on a board | substrate. The figure explaining the discharge method. The figure explaining the discharge method. The figure explaining the pattern of the drive waveform which drives the piezoelectric element which concerns on 2nd Embodiment. The flowchart of the manufacturing process which forms the warming-up drive waveform pattern which concerns on 3rd Embodiment. The figure explaining the pattern of the drive waveform which drives a piezoelectric element. FIG. 10 is a schematic cross-sectional view of a main part of a droplet discharge head according to a fourth embodiment. The electric control block diagram of a droplet discharge device. 6 is a flowchart showing a manufacturing process in which drawing is performed by preliminary discharge from a droplet discharge head.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1,96 ... Droplet discharge apparatus, 8 ... Board | substrate as a workpiece | work, 15,94 ... Droplet discharge head, 21 ... Weight measuring apparatus as discharge amount measurement part, 31, 31a, 31d, 31e, 31f, 31h, 31j , 31k ... nozzle, 33 ... functional liquid, 36 ... droplet, 65 ... saucer as preliminary discharge area, 70 ... equilibrium nozzle temperature as drawing nozzle temperature, 71 ... equilibrium discharge frequency as warm-up discharge frequency.

Claims (6)

A discharge method for discharging functional liquid from a nozzle,
A preliminary discharge step of discharging the functional liquid from the nozzle to a preliminary discharge region;
A discharge step of discharging the functional liquid from the nozzle onto a workpiece;
In the preliminary ejection step, the functional liquid is ejected until the nozzle reaches substantially the same temperature as that in the ejection step. The discharge method according to claim 1,
A discharge method, further comprising a discharge amount adjustment step of adjusting the discharge amount of the functional liquid discharged from the nozzle. The discharge method according to claim 1 or 2,
A preliminary measurement step of measuring the number of discharges until the nozzle discharges the functional liquid and reaches a temperature in the discharge step;
In the preliminary discharge step, the discharge is performed by discharging the functional liquid at the number of discharges. The discharge method according to claim 1,
In the preliminary discharge step, the discharge is performed using substantially the same discharge pattern as the discharge pattern for discharging the functional liquid and stopping the discharge in the discharge step. The discharge method according to claim 1 or 2,
A preliminary discharge pattern forming step for forming a preliminary discharge pattern for discharging the functional liquid and stopping the discharge, which is formed at substantially the same ratio as the ratio of the discharge time and the discharge stop time of the functional liquid in the discharge process. With
In the preliminary ejection step, ejection is performed using the preliminary ejection pattern. The discharge method according to claim 1 or 2,
The preliminary discharge step includes a nozzle temperature measurement step for measuring the temperature of the nozzle,
A temperature determination step of determining whether or not to discharge the functional liquid from the nozzle according to the temperature of the nozzle measured in the nozzle temperature measurement step,
In the preliminary ejection step, the functional liquid is ejected so that the nozzle temperature reaches a predetermined temperature while repeating the nozzle temperature measurement step and the temperature determination step.

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