CN100586718C - Pattern forming method, droplet discharge device, electro-optic device and liquid crystal display device - Google Patents

Abstract

In the pattern forming method of the present invention, the pattern formed of the liquid droplets is formed on the substrate by ejecting the liquid droplets of the pattern forming material toward the substrate. The droplets are ejected in a direction inclined at a predetermined angle from a normal line of the substrate to a predetermined direction, and the ejection is performed at a predetermined distance in the predetermined direction. The predetermined angle is set based on the diameter of the liquid droplet and the predetermined distance so that a size of an ink dot made of each liquid droplet landing on the substrate in the predetermined direction is equal to or larger than the predetermined distance. Therefore, the film thickness uniformity of the pattern can be improved.

Description

Pattern forming method, droplet discharge device, electro-optic device and liquid crystal display device

technical field

The present invention relates to a pattern forming method, a droplet discharge device, an electro-optic device and a liquid crystal display device.

Background technique

The manufacturing process of a display device or a semiconductor device includes a large number of patterning (patterning) steps in which a film deposited on a substrate is patterned into a desired shape to form a patterned film.

In recent years, in such a pattern forming process, in order to improve productivity, an inkjet method in which liquid droplets discharged onto a substrate are solidified to form a patterned film in a self-aligned manner has been utilized. Since the inkjet method can form a patterned film corresponding to the droplet shape on the substrate, it is not necessary to form a mask for patterning, and the number of steps in the pattern formation process can be reduced.

However, in the case of forming a patterned film by an inkjet method, if the landed droplets do not diffuse and wet on the substrate surface, the uneven shape of the droplets will be reflected in the pattern shape, which will damage the patterned film. flatness and film thickness uniformity.

Therefore, in such an inkjet method, it has been proposed to expand the diffusion and wetting of the landed droplets. For example, in Japanese Patent Application Laid-Open No. 2005-131498, the velocity component along the tangential direction of the substrate is given to the ejected liquid droplets by inclining the ejection direction of the liquid droplets relative to the normal line of the substrate. Thereby, it is possible to diffuse and wet the landing droplet along the tangential direction of the substrate by the angle (inclination angle) formed between the normal direction of the substrate and the discharge direction.

However, in the above-mentioned inkjet method, in the case of forming patterned films with different film thicknesses, that is, in the case of changing the total discharge amount per unit area, generally speaking, each droplet The capacity is kept constant, and the ejection interval of liquid droplets is changed. For example, in the case of forming a patterned film of a thin film, the droplet capacity of each drop is kept constant, and the scanning speed of the substrate relative to the nozzle is increased, or the operating cycle of the ejection operation is extended, so that the ejection of the droplets The output interval is expanded. As a result, the droplet discharge operation can be stabilized, and the reproducibility of the total discharge amount, that is, the film thickness reproducibility of the patterned film can be ensured.

However, in the aforementioned Japanese Unexamined Patent Application Publication No. 2005-131498, only the flight deflection of the ejected liquid droplet and the scattering of the landed liquid droplet are considered, and the inclination angle of the ejection direction is specified within a wide range. Therefore, as shown in FIG. 10 , in the case of forming a patterned film of a thin film by enlarging the discharge interval W of the liquid droplets Fb, if the inclination angle θ of the discharge direction A is small, the impact diameter R1 of the liquid droplets Fb is smaller than The ejection interval W of the liquid droplets Fb is short. Then, the landing droplets Fb are dispersed on the substrate Sb, respectively.

As a result, there is a problem that the uneven shape of each droplet Fb is reflected in the shape of the patterned film, so that the film thickness of the patterned film is significantly uneven.

Contents of the invention

The present invention was made to solve the above-mentioned problems, and an object of the present invention is to provide a pattern forming method and a droplet ejection device that improve the film thickness uniformity of a pattern such as a patterned film made of droplets. Another object of the present invention is to provide an electro-optical device and a liquid crystal display device including a pattern formed using such a droplet discharge device.

A pattern forming method for forming a pattern composed of liquid droplets on a substrate by spraying liquid droplets of a pattern forming material toward a substrate, and the liquid droplets are sprayed in a direction inclined at a predetermined angle from a normal line of the substrate to a predetermined direction. and the ejection is carried out at a predetermined distance in the predetermined direction, and the predetermined angle is set based on the diameter of the droplet and the predetermined distance so that the ink formed by each droplet landing on the substrate The size of the point in the specified direction is above the specified distance, and when the diameter of the droplet is R, the specified distance is W, and the specified angle is θ, the specified angle is set to satisfy: arccos(R/W)≤θ<90.

A droplet ejection device forms a pattern made of droplets on a substrate by ejecting droplets of a pattern forming material toward a substrate. The liquid droplets are ejected in a direction inclined by a predetermined angle from the normal line of the substrate to a predetermined direction, and the ejection is performed at a predetermined distance in the predetermined direction, the liquid droplet ejection device has: a discharge port forming surface, It is disposed opposite to the substrate, and a plurality of ejection ports for ejecting the liquid droplets are arranged in a row on the ejection port forming surface; a tilting mechanism is used to make the ejection port forming surface surround the ejection port The tilting axis extending parallel to the direction in which the outlets are arranged is tilted; the angle setting mechanism controls the tilting mechanism to set the predetermined angle based on the diameter of the liquid droplet and the predetermined distance, so that the droplet falls on the substrate The size of the ink dot formed by each liquid droplet in the predetermined direction is greater than the predetermined distance, and the angle setting mechanism includes: a tilting information generation mechanism that determines the angle based on the diameter of the liquid droplet and the predetermined distance. generating tilting information for controlling the tilting mechanism so that the external dimension of the ink dot in the predetermined direction is equal to or greater than the predetermined distance; and a control means based on the tilting information generated by the tilting information generating means To control the tilting mechanism, when the diameter of the droplet is R, the specified distance is W, and the specified angle is θ, the tilting information generating mechanism generates the tilting information to satisfy: arccos(R/ W)≤θ<90.

An electro-optical device includes a substrate patterned using the above-mentioned droplet discharge device.

A liquid crystal display device includes a substrate on which an alignment film is formed using the above-mentioned droplet discharge device.

Description of drawings

FIG. 1 is a perspective view showing a liquid crystal display device in one embodiment of the present invention;

2 is a cross-sectional view showing the liquid crystal display device of FIG. 1;

3 is a perspective view showing a droplet ejection device in the same embodiment;

4 is a perspective view showing a droplet ejection head of the droplet ejection device of FIG. 3;

Fig. 5, Fig. 6, Fig. 7 are the side views showing the same liquid drop discharge head;

FIG. 8 is an explanatory diagram for explaining the droplet ejection operation of the droplet ejection device of FIG. 3;

9 is an electrical block circuit diagram showing the electrical configuration of the droplet ejection device of FIG. 3;

Fig. 10 is a schematic side view showing a conventional droplet discharge device.

Detailed ways

Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 to 9 . First, a liquid crystal display device 10 as an electro-optic device having an alignment film (pattern) formed by the pattern forming method of the present invention will be described. FIG. 1 is a perspective view of a liquid crystal display device 10 , and FIG. 2 is a cross-sectional view taken along line A-A of FIG. 1 .

In FIG. 1 , an edge light type backlight 12 is provided below a liquid crystal display device 10. The backlight has a light source 11 such as an LED and is formed in a quadrangular plate shape.

Above the backlight 12 is provided a quadrangular plate-shaped liquid crystal panel 13 having substantially the same size as the backlight 12 . Then, the light emitted from the light source 11 is irradiated to the liquid crystal panel 13 .

The liquid crystal panel 13 is provided with an element substrate 14 and an opposing substrate 15 which are opposed to each other. As shown in FIG. 2 , the element substrate 14 and the counter substrate 15 are bonded together via a quadrangular frame-shaped sealing material 16 made of a photocurable resin. Furthermore, a liquid crystal 17 is sealed in a gap between these element substrates 14 and the counter substrate 15 .

An optical substrate 18 such as a polarizing plate and a retardation plate is bonded to the lower surface (side surface on the backlight 12 side) of the element substrate 14 . The optical substrate 18 linearly polarizes the light from the backlight 12 to the liquid crystal 17 . On the upper surface of the element substrate 14 (the side facing the substrate 15 : element formation surface 14 a ), a plurality of scanning lines Lx extending substantially in one direction (X arrow direction) are arranged and formed. The scanning line Lx is electrically connected to the scanning line driving circuit 19 disposed on one side of the element substrate 14 . The scanning signal is input from the scanning line driving circuit 19 at predetermined timing. In addition, a plurality of data lines Ly extending substantially over the entire area in the Y arrow direction are arranged and formed on the element formation surface 14 a. The data line Ly is electrically connected to the data line driving circuit 21 disposed on the other side of the element substrate 14, and receives input of a data signal based on display data from the data line driving circuit 21 at a predetermined timing.

On the element formation surface 14a, a plurality of pixels 22 connected to the corresponding scanning lines Lx and data lines Ly and arranged in a matrix are formed at positions where the scanning lines Lx and the data lines Ly intersect. Each pixel 22 includes a control element (not shown) such as a TFT, and a light-transmitting pixel electrode 23 made of a transparent conductive film or the like.

In FIG. 2 , an alignment film 24 subjected to alignment treatment by rubbing is laminated on the entire upper side of each pixel 22 . The alignment film 24 is a thin patterned film made of an alignment polymer such as alignment polyimide, and functions to set the liquid crystal 17 in a predetermined alignment state in the vicinity of the corresponding pixel electrode 23 . The alignment film 24 is formed by an inkjet method. That is, by spraying an alignment film forming material F (refer to FIG. 6 ) as a pattern forming material in which an alignment polymer is dissolved in a predetermined solvent, as a liquid droplet Fb (refer to FIG. 7 ), the entire upper side of the pixel 22 is sprayed. The landed droplets Fb are dried to form an alignment film 24 .

On the upper surface of the counter substrate 15, a polarizing plate 25 for emitting linearly polarized light perpendicular to the light from the optical substrate 18 to the outside (upward in FIG. 2 ) is arranged. On the entire lower surface of the opposing substrate 15 (the side surface on the element substrate 14 side: the electrode formation surface 15a), an opposing electrode 26 is laminated. constitute. The opposing electrode 26 is electrically connected to the data line driving circuit 21 , and a predetermined common potential is applied to the opposing electrode 26 from the data line driving circuit 21 . An alignment film 27 subjected to alignment treatment by rubbing is laminated on the entire lower surface of the counter electrode 26 . The alignment film 27 is also formed by the inkjet method like the alignment film 24, and works to set the liquid crystal 17 in a predetermined alignment state in the vicinity of the counter electrode 26.

Then, based on the line-sequential scanning, the scanning lines Lx are selected one by one at a predetermined timing, and the control element of each pixel 22 is turned on only during the respective selection periods. Then, a data signal based on the display data from the corresponding data line Ly is output to each pixel electrode 23 corresponding to each control element. When a data signal is output to each pixel electrode 23 , based on the potential difference between each pixel electrode 23 and the counter electrode 26 , the alignment state of the corresponding liquid crystal 17 is modulated. That is, the polarization state of the light from the optical substrate 18 is modulated for each pixel 22 . Then, an image based on the display data is displayed on the upper side of the liquid crystal panel 13 according to whether or not the modulated light passes through the polarizing plate 25 .

Next, a droplet ejection device 30 for forming the alignment film 27 (orientation film 24 ) described above will be described with reference to FIGS. 3 to 9 .

In FIG. 3 , the droplet discharge device 30 is an alignment film forming device in this embodiment, and the droplet discharge device 30 is equipped with a base 31 formed in a rectangular parallelepiped shape, and on the upper surface of the base 31, a There are a pair of guide grooves 32 extending along its length direction (X arrow direction). Above this base 31, there is provided a substrate mounting table 33 as a moving mechanism drivingly coupled to the output shaft of an X-axis motor MX (refer to the upper left in FIG. The guide groove 32 reciprocates (scans in the direction of the X arrow) at a predetermined speed (transportation speed Vx) in the direction of the X arrow and in the opposite direction of the X arrow.

On the upper surface of the substrate mounting table 33, a mounting surface 34 capable of mounting the opposing substrate 15 with the opposing electrode 26 on the upper side is formed. The positioning is fixed. In addition, in the present embodiment, although the counter substrate 15 is placed on the placement surface 34, it is not limited thereto, and the element substrate 14 may be placed with the pixel electrodes 23 on the upper side. structure.

Door-shaped guide members 35 are arranged on both sides of the base 31 in the Y-arrow direction, and a pair of upper and lower guide rails 36 extending in the Y-arrow direction are formed on the guide member 35 .

In addition, the guide member 35 is equipped with a carriage 37 drivingly connected to the output shaft of the Y-axis electrode MY (refer to the lower left of FIG. Reciprocate in the opposite direction of the Y arrow (scan along the direction of the Y arrow). Inside the carriage 37, an ink cartridge 38 is arranged to accommodate the alignment film forming material F (refer to FIG. 6 ) in a derivable manner. The droplet discharge head 41.

4 is a schematic perspective view of the carriage 37 (droplet discharge head 41 ) viewed from below, and FIGS. 5 and 6 are schematic side views of the carriage 37 and droplet discharge head 41 viewed from the side in the Y arrow direction.

In FIG. 4 , a rectangular parallelepiped guide mounting table 39 extending in the Y arrow direction is disposed below the carriage 37 (upper side in FIG. 4 ). On the lower surface (upper surface in FIG. 4 ) of the guide mounting table 39 , a concave curved surface (guiding surface 39 a ) having an arcuate cross section is formed over substantially the entire area of the guide mounting table 39 in the Y arrow direction. The guide surface 39a is formed such that the center of curvature 39C (refer to the lower center in FIG. 5 ) is located directly below the guide mounting table 39 and along the upper surface of the counter electrode 26 placed on the substrate mounting table 33 . .

In FIG. 4 , on the guide mounting table 39 , a tilt table 40 extending in the Y arrow direction and forming a semi-conical (kamahoko-like) shape constituting a tilt mechanism is arranged. On one side surface of the tilt table 40 , a convex curved surface (sliding surface 40 a ) corresponding to the guide surface 39 a is formed on the side surface (lower surface in FIG. 4 ) on the side of the guide mounting table 39 . Further, on the other side of the tilt table 40 , a plane (mounting surface 40 b ) parallel to the opposing substrate 15 is formed on the side (the upper surface in FIG. 4 ) opposite to the sliding surface 40 a.

The tilt table 40 is drive-connected to the output shaft of the tilt motor MR (refer to the upper right in FIG. 9 ) built in the carriage 37, and receives the driving force of the tilt motor MR so that its sliding surface 40a moves along the guide surface 39a. Swipe (reverse). That is, the sliding surface 40 a of the tilting table 40 is on the same plane as the guiding surface 39 a, and the mounting surface 40 b thereof tilts relative to the opposing substrate 15 around the center of curvature 39C on the opposing electrode 26 . In other words, the mounting surface 40b is tilted around a tilt axis extending in the Y arrow direction.

And a signal for tilting the mounting surface 40b is supplied to the tilting motor MR. Then, the tilting motor MR is driven forward or reverse at a predetermined rotational speed, and the mounting surface 40b of the tilting table 40 is tilted around the center of curvature 39C.

In addition, in this embodiment, as shown by the solid line in FIG. 5 , at the arrangement position of the tilt table 40, the normal direction of the mounting surface 40b (hereinafter referred to as the ejection direction A) and the normal direction of the opposing substrate 15 are aligned. (Z arrow direction) The parallel arrangement position is called "initial position". In addition, as shown by the two-dot chain line in FIG. 5 , the arrangement position of the tilting table 40, that is, the arrangement of the state in which the ejection direction A is inclined by a predetermined angle (inclination angle θ) from the normal line of the counter substrate 15 to the X arrow direction The position is called the "tilted position".

In FIG. 4 , a droplet discharge head (hereinafter referred to as a discharge head) 41 extending in the direction of the arrow Y and formed in a rectangular parallelepiped shape is fixed to the mounting surface 40b. A nozzle plate 42 is provided on the lower side (upper side in FIG. 4 ) of the shower head 41, and a nozzle plate 42 parallel to the mounting surface 40 b is formed on the opposing substrate 15 side (upper side in FIG. 4 ) of the nozzle plate 42 as a discharge port. The nozzle forming surface 42a is formed. On the nozzle forming surface 42a, a plurality of nozzles N serving as ejection ports are arranged and formed at equal intervals along the Y arrow direction.

In FIG. 5, each nozzle N is formed through the nozzle plate 42 along the normal direction of the nozzle forming surface 42a (mounting surface 40b), that is, along the ejection direction A, and when the tilt table 40 is located at the "initial position", Each nozzle N is arranged so as to be located in the Z arrow direction (opposite side to the discharge direction A) of the curvature center 39C. In the present embodiment, the positions corresponding to the center of curvature 39C and the ejection direction A of each nozzle N are referred to as landing positions PF.

Then, the tilting motor MR is driven in the forward direction to move the tilting body 40 from the "initial position" arrangement to the "tilt position". Then, as shown in FIG. 5 , each nozzle N rotates to the right with the center of curvature 39C (corresponding landing position PF) as the center of rotation, and its forming direction is in the direction relative to the normal line (Z arrow direction) of the opposing substrate 15. The X arrow direction is inclined at an inclination angle θ. Accordingly, each nozzle N can maintain the position of the corresponding landing position PF when the forming direction is inclined, and can maintain the distance from the corresponding landing position PF at a predetermined distance (flying distance L). That is, the droplet ejection device 30 is configured to maintain the landing accuracy of the droplets Fb ejected from the respective nozzles N when the ejection direction A is changed.

In FIG. 6 , a chamber 43 communicating with the ink cartridge 38 is formed on the opposite side of each nozzle N in the ejection direction A, and the alignment film forming material F from the ink cartridge 38 is supplied to the corresponding nozzle N. On the opposite side of the discharge direction A of each chamber 43 , a vibrating plate 44 capable of vibrating in the discharge direction A and its opposite direction is attached to expand and/or reduce the volume of the chamber 43 . On the upper side of the vibrating plate 44, a plurality of piezoelectric elements PZ corresponding to the respective nozzles N are arranged. Each piezoelectric element PZ receives a signal for driving and controlling the piezoelectric element PZ (piezoelectric element driving signal COM: refer to the lower left of FIG. It vibrates in the opposite direction.

Here, as shown in FIG. 7 , on the opposite electrode 26 (opposite substrate 15 ), in the region where the alignment film 27 is formed, equal intervals (discharging intervals W) along the direction of the arrow X are defined for making the droplets Fb Landing grid point (target position P).

Next, the moving and tilting table 40 is placed at the "tilt position", and the transfer of the substrate mounting table 33 in the direction of the X arrow is started. Then, the piezoelectric element drive signal COM is supplied to each piezoelectric element PZ when each landing position PF is at a position (target position P) on the counter electrode 26 for landing the droplet Fb.

Then, the volume of each chamber 43 expands and/or shrinks, and the meniscus (interface of the alignment film forming material F) in each nozzle N vibrates. When the meniscus in each nozzle vibrates, as shown in FIG. 7 , the alignment film forming material F of a predetermined weight corresponding to the piezoelectric element drive signal COM is released from the corresponding nozzle N as having a predetermined diameter (droplet diameter R0 : is ejected with reference to the liquid droplet Fb of FIG. 8 ). Each of the ejected droplets Fb flies for a flight distance L at a predetermined speed (discharge speed Vf) along the formation direction of each nozzle N, that is, the ejection direction A inclined by the inclination angle θ, and finally lands on the opposite The area of the target position P (landing position PF) on the electrode 26 .

In addition, the piezoelectric element driving signal COM of this embodiment is generated based on the waveform data WD (see FIG. 9 ) set in advance according to experiments, etc., and the meniscus is vibrated smoothly, and the weight of the droplet Fb is set to be stable. Specified weight. That is, the droplet discharge device 30 of the present embodiment discharges each droplet Fb by the common piezoelectric element drive signal COM (waveform data WD), and stabilizes the diameter of each droplet Fb at the droplet diameter R0. .

Then, when the liquid droplet Fb lands on the region of the target position P, the shape of the liquid droplet Fb after landing expands by an amount inclined in the discharge direction A in the direction of the X arrow. For example, as the inclination angle θ becomes smaller, the shape of the droplet Fb after landing is closer to a circle centered on the landing position PF as the inclination angle θ becomes smaller when viewed from the direction of the Z arrow. Conversely, as the inclination angle θ increases, the shape of the droplet Fb after landing is formed in an elliptical shape extending in the direction of the X arrow as the inclination angle θ becomes larger when viewed from the direction of the Z arrow.

Therefore, the inventors of the present invention found that by making the shape of the landed liquid droplet Fb close to the projected image of the liquid droplet Fb with the ejection direction A as the projection direction, it is possible to define the direction of the landed liquid droplet Fb in the X arrow direction. The landing diameter R1 of the above size, that is, the lower limit value of the size of the ink dot formed by the landing droplet in the direction of the X arrow.

That is, if the shape of the landed droplet Fb is close to the projected image of the droplet Fb, then as shown in FIG.

R1=R0/cosθ

And, to each ejected liquid droplet Fb, due to the inclination of the ejection direction A, a velocity component in the X arrow direction corresponding to the inclination angle θ is added thereto (tangential direction velocity Vfx=Vf×sinθ: refer to FIG. 7 ) . In addition, a relative velocity corresponding to the conveyance velocity Vx can be applied in the direction opposite to the X-arrow direction to each discharged liquid droplet Fb by the conveyance velocity Vx relative to the substrate 15 .

Therefore, the shape of the dropped droplet Fb expands its landing diameter R1 in the direction of the X arrow by the amount of the tangential speed Vfx and the transport speed Vx. That is, the landing diameter R1 of the droplet Fb can be derived from the following formula from the droplet diameter R0 and the inclination angle θ.

R1≥R0/cosθ

Furthermore, in the present embodiment, in the step of discharging the liquid droplets Fb, the inclination angle θ is set so that the above-mentioned impact diameter R1 is equal to or larger than the above-mentioned discharge interval W. Thereby, the droplets Fb arranged on the opposing substrate 15 can be reliably bonded to each other in the direction of the arrow X.

In addition, in the droplet discharge device 30 of the present embodiment, the inclination angle θ satisfying θ=arccos(R0/W) is set using the droplet diameter R0 and the discharge interval W, but it is not limited thereto, and may be The inclination angle θ satisfying arccos(R0/W)≦θ<90 is set.

Next, the electrical configuration of the droplet ejection device 30 configured as described above will be described with reference to FIG. 9 .

In FIG. 9, the control device 51 constituting the angle setting means includes a CPU, RAM, ROM, etc. constituting the tilt information generating means and the control means. Furthermore, the control device 51 scans the substrate stage 33 and the carriage 37 and drives and controls the piezoelectric elements PZ of the shower head 41 according to various data and various programs stored in RAM, ROM, or the like.

An input device 52 , an X-axis motor drive circuit 53 , a Y-axis motor drive circuit 54 , a head drive circuit 55 , and a tilting mechanism drive circuit 56 are connected to the control device 51 .

The input device 52 has operation switches such as a start switch and a stop switch, and inputs various operation signals to the control device 51, and uses information on the target film thickness of the alignment film 27 formed on the opposing substrate 15 as a predetermined film thickness. The information It is input to the control device 51 .

Furthermore, the film thickness information It is input to the control device 51 from the input device 52 . Then, the control device 51 receives the film thickness information It from the input device 52, calculates the total weight of the alignment film forming material F ejected on the counter electrode 26, and based on the calculated total weight and the droplet corresponding to the waveform data WD The weight of Fb is used to calculate the discharge interval W (position coordinates of each target position P) of the liquid droplets Fb. After calculating the position coordinates of each target position P, the control device 51 generates and stores bitmap data BMD for ejecting the liquid droplets Fb and tilt data RD corresponding to the ejection interval W.

The bitmap data BMD is data in which the value of each bit (0 or 1) corresponds to each target position P on the counter electrode 26, and is data in which the piezoelectric element PZ is turned on or off corresponding to the value of each bit. Furthermore, the bitmap data BMD is defined so that the liquid droplets Fb are ejected every time the respective landing positions PF are located at the respective corresponding target positions P.

The tilt data RD is data in which the tilt angle θ corresponds to the rotation speed of the tilt motor MR. The inclination angle θ is set so as to satisfy θ=arccos(R0/W) based on the discharge interval W and the droplet diameter R0 corresponding to the waveform data WD.

The X-axis motor drive circuit 53 rotates the X-axis motor MX that reciprocates the substrate stage 33 in forward or reverse directions in response to a drive control signal from the control device 51 corresponding to the X-axis motor drive circuit 53 . The X-axis motor drive circuit 53 is connected to the X-axis motor rotation detector MEX, and receives a detection signal from the X-axis motor rotation detector MEX. The X-axis motor driving circuit 53 calculates the movement direction and movement amount of the substrate stage 33 (relative substrate 15) based on the detection signal from the X-axis motor rotation detector MEX, and generates information related to the current position of the substrate stage 33 as The stage position information SPI. Then, the control device 51 receives the stage position information SPI from the X-axis motor drive circuit 53 and outputs various signals.

The Y-axis motor drive circuit 54 rotates the Y-axis motor MY that reciprocates the carriage 37 forward or reverse in response to a drive control signal corresponding to the Y-axis motor drive circuit 54 from the control device 51 . A Y-axis motor rotation detector MEY is connected to this Y-axis motor drive circuit 54, and a detection signal from the Y-axis motor rotation detector MEY is input. The Y-axis motor driving circuit 54 calculates the moving direction and the moving amount of the carriage 37 (head unit 30) based on the detection signal from the Y-axis motor rotation detector MEY, and generates information related to the current position of the carriage 37 as the carriage Location information CPI. Then, the control device 51 receives the carriage position information CPI from the Y-axis motor drive circuit 54, and outputs various drive signals.

In detail, the control device 51, based on the stage position information SPI and the carriage position information CPI, before the opposite substrate 15 enters directly under the carriage 37, based on the scanning amount (moving or retracting) of the opposite substrate 15 The corresponding bitmap data BMD is synchronized with a predetermined block signal to generate a discharge control signal SI. Then, the control device 51 serially transmits the generated ejection control signal SI to the head driving circuit 55 every time the carriage 37 is scanned.

In addition, the control device 51 generates, based on the stage position information SPI, a signal for outputting the piezoelectric element drive signal COM based on the waveform data WD to the piezoelectric element PZ every time each landing position PF is located at the corresponding target position P. signal (spray timing signal LP). Then, the control device 51 sequentially outputs the generated discharge timing signal LP to the head drive circuit 55 .

The head drive circuit 55 is connected to the head 41 and is supplied with waveform data WD, a discharge control signal SI, and a discharge timing signal LP from the control device 51 . The ejection head drive circuit 55 receives the ejection control signal SI from the control device 51, makes the ejection control signal SI correspond to each piezoelectric element PZ, and performs sequential serial/parallel conversion. Then, each time the ejection head drive circuit 55 receives the ejection timing signal LP from the control device 51, based on the serial/parallel converted ejection control signal SI, the piezoelectric element drive signal COM based on the waveform data WD It is supplied to each piezoelectric element PZ. That is, the head drive circuit 55 supplies the piezoelectric element drive signal COM to the corresponding piezoelectric element PZ every time each landing position PF is located at the target position P.

The tilting mechanism driving circuit 56 responds to the tilting data RD from the control device 51 to rotate the tilting motor MR that tilts the tilting table 40 forward or backward. A tilting motor rotation detector MER is connected to this tilting mechanism drive circuit 56, and a detection signal from the tilting motor rotation detector MER is input. The tilt mechanism drive circuit 56 calculates the tilt angle θ (actual tilt angle) of the tilt table 40 based on the detection signal from the tilt motor rotation detector MER. In addition, the tilting mechanism drive circuit 56 generates information on the calculated actual tilt angle as the tilt table information RPI, and outputs it to the control device 51 .

Next, a method of forming the alignment film 27 on the counter substrate 15 using the aforementioned droplet discharge device 30 will be described.

First, as shown in FIG. 3 , the opposing substrate 15 is placed on the substrate mounting table 33 . At this time, the substrate stage 33 is arranged on the opposite side of the carriage 37 in the direction of the arrow X, and the carriage 37 is arranged on the sidemost side of the guide member 35 in the direction opposite to the direction of the arrow Y. Moreover, the tilt table 40 is arrange|positioned at the said "initial position".

From this state, the operation input device 52 inputs the film thickness information It to the control device 51 . Then, the control device 51 generates and stores bitmap data BMD and tilt data RD based on the film thickness information It.

After the bitmap data BMD and the tilt data RD are generated, the control device 51 outputs the tilt data RD to the tilt mechanism drive circuit 56 to dispose and move the tilt table 40 to the "tilt position". When the mobile tilting table 40 is configured, the control device 51 receives the tilting table information RPI from the tilting mechanism driving circuit 56, and judges whether the actual tilting angle is the tilting angle θ corresponding to the tilting data RD. That is, the control device 51 judges whether or not the actual inclination angle is an inclination angle θ satisfying θ=arccos(R0/W).

Then, if it is determined that the actual tilt angle is the tilt angle θ corresponding to the tilt data RD (tilt table 40 is installed), the control device 51 drives and controls the Y-axis motor MY to arrange the moving carriage 37 . Then, when the opposite substrate 15 is conveyed in the X arrow direction, the carriage 37 (each nozzle N) is provided so that each impact position PF is located on the scanning path of the corresponding target position P (X arrow direction). , the control device 51 drives and controls the X-axis motor MX to start conveying the substrate mounting table 33 (opposite substrate 15 ) in the direction of the X arrow.

At this time, the control device 51 synchronizes the waveform data WD with a predetermined frame signal, and outputs the waveform data WD to the head driving circuit 55 . In addition, the control device 51 generates a discharge control signal SI for synchronizing the bitmap data BMD corresponding to one scan amount of the substrate stage 33 with a predetermined frame signal, and the control device 51 generates The ejection control signal SI is transmitted serially to the shower head driving circuit 55.

Finally, the control device 51, based on the stage position information SPI and the carriage position information CPI, outputs the ejection timing control signal LP each time each landing position PF is located at each grid point on the opposing motor 26, and executes the ejection control based on The droplet ejection operation of the signal SI.

That is, the control device 51 supplies the piezoelectric element driving signal COM corresponding to the waveform data WD to each piezoelectric element PZ at the timing when each landing position PF is located at the target position P, and ejects the alignment film forming material F from each nozzle N at once. The droplet Fb.

At this time, the ejected liquid droplets Fb fly at the ejection speed Vf along the ejection direction A inclined by the inclination angle θ, and successively land on the target positions P separated by the ejection interval W along the X arrow direction. area. The ejection direction A of each landing droplet Fb is inclined at an inclination angle θ close to the approximate shape of the landing, and its landing diameter R1 is greater than or equal to the ejection interval W. Then, each landing droplet Fb further expands its landing diameter R1 by the relative speed corresponding to its tangential speed Vfx and transport speed Vx. Therefore, each liquid droplet Fb ejected onto the counter electrode 26 is reliably joined in the direction of the X arrow.

Thus, a liquid film having a uniform film thickness can be formed by joining the droplets Fb, and the alignment film 27 having a uniform film thickness can be formed by drying the liquid film. When the alignment film 27 is formed on the counter substrate 15 , the alignment film 27 is subjected to known polishing treatment.

On the other hand, the alignment film 24 is also formed on the element substrate 14 by the droplet ejection device 30 in the same manner, and the same polishing treatment is performed on the alignment film 24 . Then, sealing material 16 is formed on element substrate 14, liquid crystal 17 is arranged in a region surrounded by sealing material 16, and element substrate 14 and counter substrate 15 are bonded together to form liquid crystal panel 13.

Next, effects of the present embodiment configured in this way will be described below.

(1) According to the above-mentioned embodiment, based on the droplet diameter R0 of the ejected liquid droplet Fb and the ejection interval W of the liquid droplet Fb, the inclination angle θ with respect to the normal line of the substrate 15 and the ejection direction A is set, The impact diameter R1 of the liquid droplet Fb is set to be equal to or greater than the discharge interval W of the liquid droplet Fb.

Therefore, it is possible to reliably receive the landed liquid droplet Fb in the direction corresponding to the ejection direction A. As shown in FIG. As a result, the droplets Fb arranged in the direction of the arrow X on the counter substrate 15 can be joined to each other irrespective of the change of the discharge interval W, that is, the change of the target film thickness of the alignment film 27 . Therefore, the film thickness uniformity of the alignment film 27 composed of the droplets Fb can be improved.

(2) According to the above embodiment, the impact diameter R1 of the droplet Fb is approximated by the projected image of the droplet Fb with the discharge direction A as the projection direction. Also, the inclination angle θ between the ejection direction A and the normal line is set based only on the droplet diameter R0 of the liquid droplet Fb and the ejection interval W of the liquid droplet Fb.

Therefore, the droplets Fb arranged in the direction of the arrow X on the opposing substrate 15 can be more easily joined to each other.

(3) According to the above-described embodiment, the ejection direction A is inclined from the normal to the counter substrate 15 in a direction that coincides with the scanning direction (X arrow direction) of the counter substrate 15 . Therefore, the impact diameter R1 of the droplet Fb can be further increased by the amount of the transport speed Vx to the substrate 15 . As a result, the film thickness uniformity of the alignment film 27 can be improved more reliably.

(4) According to the above embodiment, the control device 51 generates the tilt data RD related to the tilt angle θ based on the droplet diameter R0 and the discharge interval W of the droplet Fb. Then, based on the tilt data RD, the tilt motor MR is driven and controlled so that the tilt angle θ satisfies θ=arccos(R0/W). Therefore, the liquid droplets Fb arranged in the X-arrow direction on the opposing substrate 15 can be joined to each other more reliably.

In addition, the above-mentioned embodiment can also be changed as follows.

- In the above-described embodiment, the inclination angle θ is set based only on the droplet diameter R0 of the droplet Fb and the discharge interval W. However, it is not limited thereto. For example, in addition to the droplet diameter R0 of the droplet Fb and the discharge interval W, the surface tension of the droplet Fb, the viscosity of the droplet Fb, and the ejection distance of the droplet Fb may also be configured. Set the inclination angle θ according to the output speed Vf and so on. That is, the inclination angle θ is set based on at least the droplet diameter R0 of the droplet Fb and the discharge interval W of the droplet Fb.

- In the above-described embodiment, the substrate stage 33 is scanned along the side opposite to the ejection direction A when viewed from the normal direction of the opposing substrate 15 . That is, the substrate stage 33 is scanned in the direction of the arrow X, which is the direction in which the ejection direction A is inclined from the normal to the substrate 15 . However, the present invention is not limited thereto, and the substrate stage 33 may be scanned along the ejection direction A as viewed from the normal to the opposing substrate 15 . That is, the substrate stage 33 may be scanned in the direction opposite to the direction of the ejection direction A inclined from the normal to the substrate 15 , that is, in the direction of the arrow X. In this case, the inclination angle θ may be set based on the transport speed Vx of the substrate mounting table 33 in addition to the droplet diameter R0 and the discharge interval W of the droplets Fb. That is, the inclination angle θ may be set based on at least the droplet diameter R0 of the droplet Fb and the discharge interval W of the droplet Fb such that the impact diameter R1 of the droplet Fb is equal to or greater than the discharge interval W.

- In the above-mentioned embodiment, the tilting mechanism was embodied as the tilting table 40 . However, the present invention is not limited thereto. For example, the substrate mounting table 33 may be embodied as a tilting mechanism to tilt the opposing substrate 15 mounted on the substrate mounting table 33 relative to the nozzle forming surface 42a.

- In the said embodiment, the structure provided with the nozzle N of only one row was formed. However, the present invention is not limited thereto, and a configuration including multiple rows of nozzles N may be employed.

- In the above-mentioned embodiment, the pattern was embodied in the alignment film 27 of the liquid crystal display device 10 . However, the present invention is not limited thereto. For example, liquid crystal display device 10 and various types of field effect devices (FED, SED, etc.) provided on a fluorescent material to emit light by utilizing electrons emitted from an electron emitting element may also be embodied. Films, metal wiring, color filters, etc. That is, any pattern formed by the landed liquid droplets Fb may be used.

- In the above-described embodiments, the substrate is embodied as the counter substrate 15 of the liquid crystal display device 10 .

However, it is not limited thereto, and the substrate may be embodied as a silicon substrate, a flexible substrate, or a metal substrate.

- In the above-described embodiments, the electro-optical device is embodied as the liquid crystal display device 10 .

However, the present invention is not limited thereto. For example, the electro-optical device may be embodied as an electroluminescence device.

Claims (10)

1. A method for forming a pattern, forming a pattern made of droplets on a substrate by ejecting droplets of a pattern forming material towards a substrate, characterized in that, The liquid droplets are ejected in a direction inclined by a predetermined angle from a normal line of the substrate to a predetermined direction, and the ejection is performed every predetermined distance in the predetermined direction, The predetermined angle is set based on the diameter of the liquid droplet and the predetermined distance, so that the size of the ink dot formed by each liquid droplet landing on the substrate in the predetermined direction is greater than or equal to the predetermined distance, When the diameter of the droplet is R, the predetermined distance is W, and the predetermined angle is θ, the predetermined angle is set to satisfy: arccos(R/W)≦θ<90. 2. The pattern forming method according to claim 1, wherein The liquid droplets are ejected from a plurality of ejection ports formed on the ejection port forming surface, and the predetermined angle is set by tilting the ejection port forming face with reference to the normal line of the substrate. 3. The pattern forming method according to claim 2, wherein: When the liquid droplets are ejected toward the substrate, the substrate moves relative to the discharge port forming surface in the predetermined direction. 4. The pattern forming method according to claim 1, wherein The pattern formed on the substrate is an alignment film. 5. A droplet ejection device for forming a pattern made of droplets on a substrate by ejecting droplets of a pattern forming material toward a substrate, characterized in that, The liquid droplets are ejected in a direction inclined by a predetermined angle from a normal line of the substrate to a predetermined direction, and the ejection is performed every predetermined distance in the predetermined direction, The droplet ejection device has: an ejection port forming surface disposed opposite to the substrate, and a plurality of ejection ports for ejecting the liquid droplets are arranged in a row on the ejection port forming surface; a tilting mechanism for tilting the discharge port forming surface about a tilt axis extending parallel to the direction in which the discharge ports are arranged; an angle setting mechanism for setting the predetermined angle by controlling the tilting mechanism based on the diameter of the liquid droplet and the predetermined distance, so that the ink dot composed of each liquid droplet landing on the substrate is within the predetermined distance. dimension in the direction is above the specified distance, The angle setting mechanism has: tilting information generation means for generating tilting information for controlling the tilting mechanism based on the diameter of the liquid droplet and the predetermined distance so that the outer dimension of the ink dot in the predetermined direction is the predetermined above the distance; a control mechanism that controls the tilt mechanism based on the tilt information generated by the tilt information generation mechanism, When the diameter of the droplet is R, the predetermined distance is W, and the predetermined angle is θ, the tilt information generation mechanism generates the tilt information so as to satisfy: arccos(R/W)≤θ<90. 6. The droplet ejection device according to claim 5, wherein: A moving mechanism is provided for relatively moving the substrate and the ejection port forming surface when the liquid droplets are ejected toward the substrate, The angle setting mechanism controls the tilting mechanism so that a moving direction of the substrate with respect to the ejection port forming surface coincides with the predetermined direction. 7. The droplet ejection device according to claim 6, wherein: The moving mechanism is a mounting table on which the substrate can be mounted, and the mounting table conveys the mounted substrate in the moving direction. 8. The droplet ejection device according to any one of claims 5 to 7, wherein: The pattern formed on the substrate is an alignment film. 9. An electro-optical device comprising a substrate patterned by the droplet discharge device according to any one of claims 5 to 7. 10 . A liquid crystal display device comprising a substrate on which an alignment film is formed using the droplet discharge device according to claim 8 .

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