KR100919411B1 - Apparatus for printing electrohydrodynamic and method thereof - Google Patents

Abstract

PURPOSE: An electrohydrodynamic printing machine used for forming a conductive line and a method thereof are provided to form the conductive line of a correct pattern regardless of materials or shape of a sprinting substrate by forming a nozzle with an electrode into one body. CONSTITUTION: An electrohydrodynamic printing machine used for forming a conductive line includes a chamber, a nozzle, a power unit, a control unit, and a fluid feed unit. The chamber(100) is laminated on the top of a silicon substrate, and receives the fluid of the constant amount. The nozzle(300) is comprised of a silicon substrate and an insulator. The silicon substrate(120) is patterned on the top of an upper electrode(110), and includes a nozzle hole. The insulator(130) is formed on the bottom of a lower electrode(140) corresponding to the upper electrode. The insulator includes the nozzle holes(121,121a,121b), and laminated on the bottom of the silicon substrate. The power unit(160) supplies nozzle driving voltage to the upper and the lower electrodes. THE control unit(150) controls voltage applied to the electrodes.

Description

Apparatus for printing electrohydrodynamic and method

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrohydrodynamic printing apparatus and method for forming conductive lines, and more particularly, to an electrohydrodynamic lens using a MEMS-based technology. The present invention relates to an electro-hydraulic printing apparatus and method capable of forming a pattern of micro-sized fine conductive lines without using a ground electrode.

In general, an electrohydrodynamic printing apparatus is composed of a nozzle in the form of a pin and a ground electrode in the form of a pin or a plate, and uses a potential difference generated by applying a voltage between the nozzle and the ground electrode. Is a device for printing.

Korean Patent No. 10-0800321 (name: "electro-hydraulic printing apparatus and method using a lens") is disclosed as a related art related to the electro-hydraulic printing apparatus, and is illustrated in FIG. 1.

As shown in FIG. 1, a conventional electrohydraulic printing apparatus includes a liquid supply unit 1, an electrohydraulic lens 2, a stage unit 3, a control unit (not shown), a power supply unit 4, a substrate (5), the nozzle 6, and the syringe pump (7).

The liquid supply 1 has a nozzle 6 for spraying a conductive liquid at a constant hydrodynamic pressure. In addition, the liquid supply unit 1 supplies the conductive liquid to the nozzle 6 using the syringe pump 7.

The electrohydraulic lens 2 is located at a distance from the nozzle 6 and has a constant height. The electrohydraulic lens 2 is also located between the nozzle 6 and the substrate 5 to make the solution sprayed from the nozzle 6 into a cone jet mode.

The stage 3 is positioned below the substrate 5 to precisely move the substrate so that the conductive lines are formed in a pattern input to the controller while maintaining the substrate 5. The stage part 3 is formed as a stage of two axes x-y so that the liquid can be patterned on the substrate according to a command of a controller capable of digital control.

The power supply 4 is connected to the nozzle 6 and the electrohydraulic lens 2 to apply a voltage to each of them.

The conventional electrohydraulic printing apparatus configured as described above has a shape of droplets (meniscus) at the end of the nozzle (6) when voltage is applied to the nozzle (6) and the electrohydraulic lens (2) by the voltage supply device (4). This deforms and a jet generated at this time forms a pattern of a form input to the substrate 5.

The conventional electrohydraulic printing apparatus needs to apply positive voltage of the same magnitude to the nozzle 6 and the electrohydrodynamic lens (2). In this case, however, the electrohydraulic lens simply affects the jet's path and printing position, and does not help form the electric field, which is the basic principle of electrohydraulic printing. Since a voltage is applied under the assumption that there is a ground electrode somewhere in the lower part of the substrate, the energy consumption is increased than when the ground electrode is disposed at a certain distance below the substrate.

In addition, in the conventional electro-hydraulic printing device, since the substrate is positioned between the positive electrode and the ground electrode, the thickness of the substrate, the degree of insulation, and the characteristics of other materials may be used. There is a problem that the shape is changed and the droplet can not be printed in the desired position, the printing cannot be carried out continuously in a stable state.

That is, when performing printing using the conventional electrohydraulic technique of the configuration as shown in FIG. 1, the following problems should be solved first.

First, since the nozzle 6 is configured in the form of a pin, it is difficult to print a large area, and a small contact area between the conductive liquid and the nozzle 6 at the tip of the nozzle 6 is small, causing shaking of the meniscus. This may occur so that the shape of the droplets is difficult to stabilize, thus making it impossible to accurately print the shape of the desired pattern.

Second, when the ground electrode is used, an error between patterns occurs because the shape of the electric field varies depending on the material and shape of the substrate positioned between the nozzle and the ground electrode.

On the other hand, nozzles manufactured using MEMS-based technology have advantages in that the nozzle array is easy, batch fabrication is possible, and miniaturization is possible due to advantages in the manufacturing process.

As another example of the conventional technology related to the MEMS-based technology, Korean Patent No. 10-0596200 (name: "dropping device and method using an electrostatic field") is disclosed and illustrated in FIG.

As shown in FIG. 2, the droplet injection device using the electrostatic field is formed of a nozzle array in which an electrohydraulic nozzle (not shown) is manufactured by MEMS-based technology, and includes a body 11 and a chamber 12. And an actuator (13), a nozzle (14), a columnar member (15), a control unit (16), and a power supply unit (17), and the actuator (13) comprises N-1 electrodes (13a) and the respective electrodes. N insulating layers 13b bonded between the layers are alternately stacked.

However, this conventional configuration has a disadvantage in that the manufacturing process is complicated because the actuator must be composed of N-1 electrodes in layers, and conical liquid injection mode is used for the purpose of spraying droplets. Is not formed, and thus there is a problem that it is impossible to generate droplets of a size smaller than the nozzle size.

The technical problem to be solved by the present invention, by forming a nozzle integrally with the electrode to enable electro-hydraulic printing without the use of a separate ground electrode to affect the material or shape of the substrate (substrate) It is to provide an electro-hydraulic printing apparatus and method capable of forming conductive lines in a precise pattern form without being received.

Another technical problem to be solved by the present invention is to reduce the size of the meniscus (meniscus) having a unit nozzle capable of attaching droplets of even finer and more uniform size to the desired substrate position without error An electrohydraulic printing apparatus and method are provided.

Another technical problem to be solved by the present invention is to enable on-off by applying a differential voltage to the nozzle array and each unit nozzle to realize a conductive line having a complex shape in one printing. An electrohydraulic printing apparatus and method are provided.

Another technical problem to be solved by the present invention is a drop on demend (DOD) method using a piezo electric material attached to a chamber (dropzode) in the form of conductive lines and a certain interval (microns) droplets (droplet) It is to provide an electro-hydraulic printing apparatus and method for enabling printing.

According to an embodiment of the present invention for achieving the above object, an electro-hydraulic printing apparatus, comprising: a chamber stacked on top of a silicon substrate and formed to have a predetermined space inside the body and containing a predetermined amount of fluid; A nozzle comprising a silicon substrate having an upper electrode patterned on an upper surface and a nozzle hole formed therein, and an insulator formed on a lower surface of a lower electrode having a pattern corresponding to the upper electrode, a nozzle hole being formed on the lower surface of the silicon substrate; A power supply unit supplying a nozzle driving voltage to the upper electrode and the lower electrode of the nozzle; A control device for controlling a voltage applied from the power supply device to the upper electrode and the lower electrode, respectively; It is coupled to one side of the chamber is an electro-hydraulic printing device having a fluid supply device for supplying a conductive fluid to the interior space.

According to another embodiment of the present invention for achieving the above object, a piezoelectric element located above the chamber and enabling the frequency control for forming a droplet of a desired size in the nozzle; electro-hydraulic printing further comprising Device.

According to another embodiment of the present invention for achieving the above object, a heater for generating bubbles for forming a droplet of a desired size in the nozzle by heating the fluid inside the chamber is installed above the nozzle inside the chamber It is an electro-hydraulic printing device further comprising.

The nozzle formed on the silicon substrate is a nozzle assembly in which a plurality of unit nozzles that can be formed by a meniscus are arranged in succession. Such a nozzle assembly may include a plurality of unit nozzles in one body, and each of The potential difference applied to the unit nozzle may be adjusted differently.

A lower voltage than the upper electrode may be applied to the lower electrode to give a potential difference for forming a conical liquid injection mode at a lower voltage.

The outlet portion of the unit nozzle may be formed in a square pyramid shape to prevent the spreading of the conductive fluid, or a coating layer may be further formed on the outlet portion of the unit nozzle to maintain hydrophobicity.

According to another embodiment of the present invention for achieving the above object, each unit is formed of a silicon substrate formed with an upper electrode and a nozzle hole, and an insulator for forming a lower electrode corresponding to the upper electrode and maintaining the distance between the electrodes. An electrohydraulic printing method in a device comprising a chamber, the chamber containing the fluid, a fluid supply device for supplying fluid to the chamber, and a power supply and a control device for supplying and controlling voltage to each unit nozzle. A method comprising: (a) receiving a conductive fluid inside a chamber; (b) setting the magnitude and time control amount of the voltage applied to the upper electrode and the lower electrode of each nozzle through the power supply and the control device to determine the shape of the meniscus formed on the nozzle and the shape of the injected fluid; Making; (c) controlling the respective nozzles on / off by applying a voltage to the upper electrode and the lower electrode with the magnitude and time control amount of the set voltage.

The electro-hydraulic printing method according to the present invention comprises the steps of: placing a piezoelectric body above the chamber to form droplets of a desired size in each nozzle through vibration control of the fluid by the piezoelectric body; Installing a heater above the chamber to form droplets having a desired size in each nozzle through controlling the amount of bubble generation by heating the fluid; It may be implemented to further include any one step.

According to the present invention, electro-hydraulic printing is performed by using nozzles in which upper and lower electrodes are integrally formed, thus eliminating the need for a grounding electrode, thereby forming conductive lines having an accurate pattern without being affected by the material or shape of the printing substrate. There is an advantage to this.

In addition, according to the present invention, by applying a differential voltage to the nozzle array and each unit nozzle to enable on-off, it is possible to implement a conductive pattern of a complex pattern in one printing, the size of the meniscus By reducing the size, droplets of finer and more uniform size can be attached to the desired substrate position without error.

1 is a diagram illustrating the configuration of an electrohydraulic printing apparatus according to the prior art.

2 is a view illustrating a configuration of a droplet ejection apparatus using an electrostatic field according to the prior art.

3 is a cross-sectional view illustrating a schematic configuration of an electrohydraulic printing apparatus according to an embodiment of the present invention.

4 is a perspective view illustrating an example in which a plurality of unit nozzles illustrated in FIG. 3 are arranged to constitute a nozzle assembly.

5A and 5B are top and bottom views, respectively, of the nozzle assembly illustrated in FIG. 4.

6 is a detailed cross-sectional view showing an example in which a coating layer is formed inside the nozzle in the electrohydraulic printing apparatus according to another embodiment of the present invention.

7A and 7B are cross-sectional views illustrating examples in which a piezoelectric body or a heater is installed above the chamber in the electrohydraulic printing apparatus according to another embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

100: chamber 110: upper electrode

120: silicon substrate 121,121a, 121b: nozzle hole

130: insulator 140: lower electrode

150: controller 160: power supply

170: fluid supply device 180: coating layer

190: piezoelectric 200: heater

210: electrohydrodynamic lens 220: substrate

300: nozzle

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 3 is a cross-sectional view illustrating a schematic configuration of an electrohydraulic printing apparatus according to an embodiment of the present invention. In particular, FIG. 3 is a cross-sectional view illustrating in detail a nozzle of a jet and droplet injector.

4 is a perspective view illustrating an example in which a plurality of unit nozzles illustrated in FIG. 3 are arranged to form a nozzle assembly, and FIGS. 5A and 5B are top and bottom views of the nozzle assembly illustrated in FIG. 4, respectively. 7 is a detailed cross-sectional view showing an example in which a coating layer is formed on an inner surface of a nozzle in an electrohydraulic printing apparatus according to another embodiment of the present invention, and FIGS. 7A and 7B are chambers in an electrohydraulic printing apparatus according to another embodiment of the present invention. Fig. 2 is a cross-sectional view showing an example in which a piezoelectric body or a heater is installed above the.

As shown in FIG. 3, the electrohydraulic printing apparatus according to the present invention includes a nozzle 300 having electrodes 110 and 140 and nozzle holes 121, 121a and 121b formed by MEMS-based technology, on top of a silicon substrate. Stacked and formed to have a predetermined space inside the body, the chamber 100 for receiving a certain amount of fluid, the fluid supply device 170 for supplying a conductive fluid, the power supply unit 160 for supplying voltage to each electrode, each electrode It is configured to include a controller 150 for controlling the applied voltage.

The nozzle 300 is formed by stacking a silicon substrate 120 serving as a body and an insulator 130 serving as a spacer for maintaining a distance between electrodes, and a nozzle hole 121a to which a meniscus is formed. And 121b and upper and lower electrodes 110 and 140 for voltage application are formed. In particular, the nozzle 300 may be configured as a nozzle assembly in which a plurality of unit nozzles that can be formed by a meniscus can be arranged in succession, as shown in FIG. 4. It is preferable to form two unit nozzles in one body.

The silicon substrate 120 serves as a body of the nozzle 300, and as shown in FIG. 5A, an upper electrode 110 to which a voltage for driving the nozzle is applied is formed, and a substrate body is formed at a portion where the upper electrode is formed. A nozzle hole 121a through which the conductive fluid can be discharged is formed. At this time, the outlet portion of the nozzle hole (121a) is preferably formed in a square pyramid, or conical shape in order to prevent the spreading of the conductive fluid as shown in Figure 5b.

The insulator 130 is stacked on the opposite side of the upper electrode forming surface of the silicon substrate, and as shown in FIG. 5B, a body serving as a spacer for maintaining a distance between upper and lower electrodes is formed, and the upper electrode is disposed on a lower surface of the body. A lower electrode 140 of a pattern corresponding to the second electrode 140 is formed. A nozzle hole 121b penetrating the body is formed in a portion where the lower electrode is formed. The nozzle hole 121b is formed at a position corresponding to the nozzle hole 121a of the silicon substrate 120. In addition, the nozzle hole (121b) is formed in a circular shape so that the nozzle hole (121a) can be opened to the outside, as shown in Figure 5b two nozzle holes (121a, 121b) overlap one nozzle hole (121) ) Is formed. The lower electrode serves to correct a potential difference between the voltage applied to the upper electrode and a printing position of the droplet and the jet.

Each nozzle as described above may be configured to maintain the hydrophobic (hydrophobic) of the droplet by further forming a coating layer 180 of the chemical at the outlet portion as illustrated in FIG.

As shown in FIG. 4, the chamber 100 forms a plurality of internal spaces for accommodating the conductive fluid and is stacked on the upper electrode forming surface of the silicon substrate 120, whereby the voltage is applied to the upper electrode. The conductive fluid can be charged. By placing the piezoelectric material 190 (see FIG. 7A) made of a piezo electric material above the chamber 100, the desired size at the outlet of the nozzle through vibration control of the fluid by the piezoelectric material 190 is achieved. It is also possible to configure so as to form droplets. In addition, by installing a heater 200 (see FIG. 7B) that can generate bubbles in the fluid by directly or indirectly heating the fluid above the chamber 100, the amount of bubbles in the fluid due to the operation of the heater is provided. It is also possible to configure it to form droplets of the desired size at the outlet of the nozzle through adjustment.

The fluid supply device 170 is coupled to one side of the chamber 100 to supply a conductive fluid to the inner space of the chamber.

The power supply unit 160 supplies a voltage for driving the nozzle to the upper electrode 110 and the lower electrode 140.

The controller 150 controls voltages applied to the upper electrode 110 and the lower electrode 140 from the power supply device 160, respectively. The control device can control the power supply so that the potential difference applied to the electrodes of each nozzle is adjusted differently, and in particular, the lower electrode is lower than the upper electrode in order to give a potential difference for forming a conical liquid mode at a low voltage. Control to apply voltage.

On the other hand, in the configuration according to another embodiment of the present invention, a piezoelectric body 190 is formed on the nozzle of the chamber 100 to form droplets of a desired size in the nozzle by the vibration of the fluid as shown in Figure 7a. . In the configuration in which the piezoelectric body 190 is installed, after the predetermined electric field is applied, the piezoelectric body 190 is driven to cause vibration in the fluid, thereby making the meniscus of the nozzle into a desired shape and using the electrohydrodynamic lens 210. It is possible to accurately jetting to the desired position on the (), and conversely, if the driving of the piezoelectric body 190 is reversed, the jetting stops because the shape of the meniscus is not efficient. Therefore, it is possible to implement electro-hydraulic printing of the drop (Drop On Demand) method by accurately dropping the droplet to the desired position by using the vibration of the fluid by the piezoelectric body.

In addition, in the configuration according to another embodiment of the present invention, a heater 200 that can generate bubbles in the chamber by heating the fluid as shown in Figure 7b above the nozzle inside the chamber 100 Install. In the configuration in which the heater 200 is installed, the fluid inside the chamber is heated by driving the heater to generate bubbles between the fluids, thereby making the meniscus of the nozzle into a desired shape and moving it to a desired position on the electro-hydraulic lens 210. It is possible to make the jetting of the precisely, and on the contrary, when the driving of the heater 200 is stopped, the jetting stops because the shape of the meniscus is not efficient. Therefore, it is possible to implement electro-hydraulic printing of the drop (Drop On Demand) method by accurately dropping the droplet to the desired position by using the bubble of the fluid by the heater.

Table 1 shows conical shapes by applying different voltages to the nozzle 300, the electrohydrodynamic lens 210, and the substrate 220 in the electrohydraulic printing apparatus according to the preferred embodiment of the present invention illustrated in FIG. 3. It is a table exemplifying the voltage when the liquid pouring mode can be formed.

                 Experimental Example One 2 3 4 5 6 Nozzle applied voltage (kV) 3.82 GND 7.00 3.12 5 GND Lens applied voltage (kV) GND 3.82 3.12 7.00 Floating Floating Substrate applied voltage (kV) Floating Floating GND GND GND 5

The voltage example table illustrated in Table 1 is an electrohydraulic when the height between the nozzle 300 and the electrohydraulic lens 210 is 5 mm and the height between the electrohydraulic lens 210 and the substrate 220 is 5 cm. An experimental example using a printing apparatus is shown.

According to Table 1, the potential difference between the nozzle and the electrohydraulic lens due to the voltage applied to the nozzle 300, the electrohydraulic lens 210, and the substrate 220 is (+,-), or (-, + It can be seen that the conical liquid injection mode can be formed in both cases. In other words, it can be seen that since there is an electrohydraulic lens, the voltage for generating a conical liquid column can be reduced.

Referring to the printing operation in the electro-hydraulic printing apparatus according to the present invention configured as described above and the operation and effect by it as follows.

First, as illustrated in FIG. 5A, a plurality of upper electrodes 110 are patterned on a top surface of the silicon substrate 120 in a desired pattern shape, and then a nozzle hole 121a penetrating the body at an end of each upper electrode pattern. To form. The nozzle hole 121a is formed in a conical or square pyramid shape that becomes wider toward the lower portion, thereby preventing the spreading of the conductive fluid. Here, the silicon substrate 120 is formed through a series of etching processes using a silicon wafer to perform the function of the unit nozzle, and serves to connect the chamber 100 and the insulator 130. In the silicon wafer, the MEMS process is applied to the silicon wafer because the meniscus formed at the outlet of the unit nozzle is formed in a cone jet mode of 1/15 to 1/120. In case of having the advantage that it is easy to adjust the size of the unit nozzle.

In addition, as shown in FIG. 5B, a plurality of lower electrodes 140 are patterned on a lower surface of the insulator 130 having a body serving as a spacer to have a pattern shape corresponding to the upper electrode 110, and then the respective lower electrodes are patterned. A nozzle hole 121b penetrating the body is formed at the end of the pattern. The nozzle hole 121b is formed to be wider than the lower width of the nozzle hole 121a formed in the silicon substrate.

Next, by stacking the silicon substrate 120 and the insulator 130 by overlapping the two nozzle holes 121a and 121b, a plurality of nozzle holes 121 are formed in the body, and a plurality of nozzle holes 121 are formed on the upper and lower surfaces of the body, respectively. The top electrode 110 and the bottom electrode 140 form a corresponding nozzle assembly. Here, the insulator 130 is attached to the silicon substrate 120 through an anodic bonding, and the nozzle hole 121b is formed to be larger than the size of the nozzle hole 121a of the silicon substrate 120.

 Subsequently, a chamber 100 having a plurality of internal spaces is stacked on the upper electrode 110 of the nozzle assembly, and a fluid supply device 170 is connected to the other side of the chamber to connect a conductive fluid to the internal space of the chamber. To be supplied and stored.

When the conductive fluid is accommodated in the interior space of the chamber 100 as described above, the power supply unit 160 and the control unit 150 which can supply voltage to each unit nozzle constituting the nozzle assembly are connected to The configuration in a state in which voltage can be applied to each electrode is completed.

Next, the upper electrode 110 and the lower portion of each unit nozzle are connected through the power supply device 160 and the control device 150 to determine the shape of the meniscus formed on the nozzle and the shape of the injected fluid. Set the magnitude and time control amount of the voltage applied to the electrode 140, and selectively apply the respective unit nozzles while applying voltage to the upper electrode 110 and the lower electrode 140 with the magnitude and time control amount of the set voltage. On-off control is performed to perform the electrohydraulic printing operation.

At this time, by supplying the respective nozzles 121 by controlling the potential difference applied to each of the upper electrode 110 and the lower electrode 140 differently, the size of the meniscus formed at the outlet of each unit nozzle (meniscus) And it is possible to determine the shape of the discharged conductive fluid by adjusting the shape, and by applying a lower voltage than the upper electrode to the lower electrode it is possible to form a conical liquid mode at a low voltage.

In addition, by placing the piezoelectric body above the chamber 100 and adjusting the frequency by the piezoelectric body, droplets having a desired size can be formed in each unit nozzle of the nozzle assembly.

In the above, the present invention has been shown and described with respect to certain preferred embodiments. However, the present invention is not limited to the above-described embodiments, and those skilled in the art to which the present invention pertains can vary as many without departing from the spirit of the technical idea of the present invention described in the claims below. Changes may be made.

Claims (21)

In electro-hydraulic printing device, A chamber 100 stacked on the silicon substrate, the chamber 100 having a predetermined space in the body and receiving a predetermined amount of fluid; The silicon substrate 120 having the upper electrode 110 patterned on the upper surface and the nozzle hole 121a formed thereon, and the lower electrode 140 having a pattern corresponding to the upper electrode are formed on the lower surface thereof, and the nozzle hole 121b is formed. A nozzle 300 including an insulator 130 stacked on a bottom surface of the substrate; A power supply unit 160 for supplying a nozzle driving voltage to the upper electrode 110 and the lower electrode 120 of the nozzle; A control device 150 for controlling a voltage applied to the upper electrode and the lower electrode from the power supply device, respectively; And a fluid supply device (170) coupled to one side of the chamber and supplying a conductive fluid to the inner space thereof. The method of claim 1, The nozzle 300 is an electro-hydraulic printing apparatus, characterized in that consisting of a nozzle assembly consisting of a plurality of unit nozzles are arranged in succession that can be formed by the meniscus (meniscus). The method of claim 2, The nozzle assembly is an electro-hydraulic printing apparatus, characterized in that formed by a plurality of unit nozzles. The method of claim 2, An electrohydraulic printing apparatus, characterized in that the potential difference applied to each unit nozzle is adjusted differently. The method of claim 1, And a lower voltage is applied to the lower electrode than the upper electrode to give a potential difference for forming a conical liquid injection mode at a low voltage. The method of claim 1, Electrostatic printing apparatus, characterized in that the outlet portion of the unit nozzle is formed in a square pyramid shape in order to prevent the spreading of the conductive fluid. The method of claim 1, Electro-hydraulic printing apparatus, characterized in that the coating layer 180 is formed to maintain the hydrophobic (hydrophobic) at the outlet of the unit nozzle. The method of claim 1, And a piezoelectric body (190) installed above the nozzle of the chamber and configured to control the vibration of the fluid to form droplets of a desired size in the nozzle. The method of claim 1, And a heater (200) installed above the nozzle inside the chamber to generate bubbles for heating the fluid inside the chamber to form droplets of a desired size in the nozzle. The method according to claim 8 or 9, The nozzle is an electro-hydraulic printing apparatus, characterized in that consisting of a nozzle assembly consisting of a plurality of unit nozzles that can be formed by the meniscus in succession. The method of claim 10, The nozzle assembly is an electro-hydraulic printing apparatus, characterized in that formed by a body of a plurality of unit nozzles. The method of claim 10, And an electric potential difference applied to each unit nozzle of the nozzle assembly in the control apparatus is different from each other. The method according to claim 8 or 9, And a lower voltage is applied to the lower electrode than the upper electrode to give a potential difference for forming a conical liquid injection mode at a low voltage. The method according to claim 8 or 9, Electrostatic printing apparatus, characterized in that the outlet portion of the nozzle is formed in a square pyramid shape in order to prevent the spreading of the conductive fluid. The method according to claim 8 or 9, Electro-hydraulic printing apparatus characterized in that the coating layer 180 is further formed to maintain the hydrophobicity at the outlet portion of the nozzle. The silicon substrate 120 having the upper electrode 110 and the nozzle hole 121a formed therein, and the lower electrode 140 having a pattern corresponding to the upper electrode are formed, and the insulator 130 maintaining the distance between the upper and lower electrodes. Comprising a plurality of unit nozzles, the chamber 100 for receiving the fluid, the fluid supply unit 170 for supplying the fluid to the chamber, and the power supply unit 160 for controlling and supplying voltage to each unit nozzle and control In an electrohydraulic printing method in a device comprising a device 150, (a) receiving a conductive fluid inside the chamber 100; (b) the upper electrode 110 and the lower electrode of each unit nozzle through the power supply device 160 and the control device 150 to determine the shape of the meniscus formed on the nozzle and the shape of the injected fluid; Setting the magnitude and time control amount of the voltage applied to 140; and (c) controlling the respective unit nozzles on / off by applying a voltage to the upper electrode 110 and the lower electrode 140 with the magnitude and time control amount of the set voltage. Electrohydraulic printing method. The method of claim 16, And applying a lower voltage to the lower electrode than the upper electrode to give a potential difference for forming a conical liquid injection mode at a low voltage. The method of claim 16, (d1) placing a piezoelectric body above the chamber, and forming droplets of a desired size in the unit nozzle through vibration control of the fluid by the piezoelectric body; electro-hydraulic printing method further comprising. The method of claim 16, (d2) installing a heater above the chamber, and forming droplets of a desired size in the unit nozzle by adjusting a bubble generation amount by heating the heater; Electro-hydraulic printing method characterized in that it further comprises. The method of claim 16, The electrohydraulic printing method, characterized in that for supplying by differently adjusting the potential difference applied to the upper electrode 110 and the lower electrode 140 of each unit nozzle. The method of claim 16, The nozzle is composed of a nozzle assembly consisting of a plurality of unit nozzles that can be formed by the meniscus successively arranged in one body, the electric potential difference is applied to each unit nozzle of the nozzle assembly is differently controlled Hydraulic printing method.