KR100976205B1 - Inkjet Head and Manufacturing Method Thereof - Google Patents

Abstract

An inkjet head and a method of manufacturing the same are disclosed. A reservoir for storing ink, an inlet port through which ink is supplied to the reservoir, a chamber for receiving ink from the reservoir, a restrictor connecting the reservoir and the chamber, a nozzle for discharging ink, and an interposition between the chamber and the nozzle An inkjet head comprising a damper portion, comprising: a first plate made of silicon, wherein a portion of the damper portion, the chamber, the reservoir, and the restrictor are formed; A vibrating plate of glass material bonded to an upper surface of the first plate to cover the chamber; A second plate of glass material bonded to a lower surface of the first plate and having a portion of the damper portion formed thereon; And the inkjet head is bonded to the lower surface of the second plate, the inkjet head including a nozzle plate of the silicon material in which the nozzle is formed, the production yield is improved, it is possible to ensure a stable quality based on the warning coupling force between the respective components.

Inkjet, Head, SOI Board, Diaphragm, Glass

Description

Inkjet head and manufacturing method thereof

The present invention relates to an inkjet head and a method of manufacturing the same.

The inkjet head uses a principle that converts an electrical signal into a physical force so that ink is ejected in the form of droplets through a small nozzle. The inkjet head is manufactured by processing various components such as a chamber, a restrictor, a nozzle, a damper, and the like on each layer, and then bonding the processed layers to each other. The inkjet technology is not only used in the graphic inkjet industry for printing on paper and textiles, but also recently, the use of inkjet technology has been expanded to manufacture electronic components such as print-based and LCD panels.

However, the inkjet printing technology for electronic components, which requires accurate and precise ejection of functional inks compared to conventional graphic printing, requires functions not required in the conventional inkjet head. For example, variations in the size and speed of discharge droplets are basically required, and in addition, high nozzle density and high frequency characteristics are required to increase production.

Conventional inkjet heads are made mainly of stainless steel (SUS), high-temperature ceramics and single crystal silicon. In the case of SUS, it is necessary to manufacture using a mold, so design change is not easy, so the head of a single crystal silicon material is receiving attention recently. In the production method using single crystal silicon wafers, elements having respective functions are processed into two or three wafers separately and bonded.

In order to fabricate the inkjet head, a SUS plate processed by punching or wet etching or the like is bonded, or a silicon wafer is processed by using a plasma processing method, and these are bonded by using a silicon direct bonding or fusion bonding method. However, the problem is that the processing of silicon joints is quite difficult and does not yield sufficient reliability and yield.

In the silicon direct bonding, the surface roughness of the silicon wafer to be bonded needs to be low. In the case of the silicon wafer subjected to the MEMS process, the surface is rough or stressed. When the silicon direct bonding is to be performed with such a silicon wafer, there is a problem that the yield falls below 50 to 70%.

The present invention provides an inkjet head and a method for manufacturing the same, which can improve production yield and ensure stable quality.

According to an aspect of the present invention, a reservoir for storing ink, an inlet for supplying ink to the reservoir, a chamber for receiving ink from the reservoir, a restrictor for connecting the reservoir and the chamber, a nozzle for discharging ink, and An inkjet head comprising a damper portion interposed between the chamber and the nozzle.

A first plate of silicon material in which a part of the damper part, the chamber, the reservoir, and the restrictor are formed; A vibrating plate of glass material bonded to an upper surface of the first plate to cover the chamber; A second plate of glass material bonded to a lower surface of the first plate and having a portion of the damper portion formed thereon; And a nozzle plate bonded to a lower surface of the second plate and including a nozzle plate on which the nozzle is formed.

In this case, a portion of the damper portion formed on the second plate may have a shape that becomes narrow toward the nozzle plate.

The first plate may be an SOI substrate, and a part of the damper portion and the reservoir may be formed by processing a lower surface of the SOI substrate, and the chamber and the restrictor may be formed by processing an upper surface of the SOI substrate. .

According to another aspect of the present invention, a reservoir for storing ink, an inlet port through which ink is supplied to the reservoir, a chamber for receiving ink from the reservoir, a restrictor for connecting the reservoir and the chamber, a nozzle for discharging ink, and A method of manufacturing an inkjet head comprising a damper portion interposed between the chamber and the nozzle,

Machining an upper surface of the first plate of silicon-containing material to correspond to the chamber and the restrictor; Machining a lower surface of the first plate so as to correspond to the damper portion and the reservoir; Processing a diaphragm of glass material so as to correspond to the inlet; Machining a second plate of glass material to correspond to the damper portion; Machining the nozzle plate of silicon material so as to correspond to the nozzle; Bonding the diaphragm to an upper surface of the first plate; Bonding the nozzle plate to a bottom surface of the second plate; And bonding a lower surface of the first plate and an upper surface of the second plate to each other.

A portion of the damper portion formed on the second plate may have a shape that narrows toward the nozzle plate, and the first plate may be an SOI substrate.

In addition, the step of processing the diaphragm made of glass material to correspond to the inlet, before the step of bonding the diaphragm to the upper surface of the first plate, forming a groove corresponding to the inlet on one surface of the diaphragm; And after the bonding of the diaphragm to the upper surface of the first plate, grinding the other surface of the diaphragm.

At this time, polishing the other surface of the diaphragm may be performed through a chemical mechanical polishing (CMP) process.

On the other hand, the step of processing the nozzle plate of silicon material to correspond to the nozzle, prior to the step of bonding the nozzle plate to the lower surface of the second plate, forming a groove corresponding to the nozzle on one surface of the nozzle plate Making; And after bonding the nozzle plate to the bottom surface of the second plate, grinding the other surface of the nozzle plate.

According to a preferred embodiment of the present invention, the production yield is improved, it is possible to ensure a stable quality based on the warning coupling force between the respective components.

As the invention allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all transformations, equivalents, and substitutes included in the spirit and scope of the present invention. In the following description of the present invention, if it is determined that the detailed description of the related known technology may obscure the gist of the present invention, the detailed description thereof will be omitted.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

Hereinafter, preferred embodiments of an inkjet head and a method of manufacturing the same according to the present invention will be described in detail with reference to the accompanying drawings. In the following description with reference to the accompanying drawings, the same or corresponding components are given the same reference numbers Duplicate description thereof will be omitted.

First, an inkjet head manufacturing method according to an aspect of the present invention will be described with reference to FIGS. 1 to 9.

1 is a flowchart illustrating a method of manufacturing an inkjet head according to an aspect of the present invention, and FIGS. 2 to 16 are views illustrating respective processes of the method of manufacturing an inkjet head according to an aspect of the present invention. 2 to 16, the first plate 10, the silicon layers 11 and 12, the damper portion 11a, the reservoir 11b, the chamber 12a, the restrictor 12b, and the inlet 12c. , Insulating layer 13, diaphragm 20, 20 ′, inlet 22, second plate 30, damper portion 32, nozzle plate 40, 40 ′, nozzle 42 are shown. .

Before describing the inkjet head manufacturing method according to the present embodiment in detail, the components of the above-described inkjet head will be briefly described with reference to FIG. 16.

The chamber 12a accommodates ink and, when pressure is applied by an actuator (not shown) formed on the upper surface of the diaphragm 20 ', means for moving the contained ink toward the nozzle 42 to eject the ink. to be.

The reservoir 11b is a means for receiving ink from the outside through the inlets 12c and 22, storing the ink, and supplying the ink to the chamber 12a.

The restrictor 12b communicates with the above-described reservoir 11b and the chamber 12a and is a means for controlling the flow of ink generated between the reservoir 11b and the chamber 12a. The restrictor 12b is formed to have a smaller cross-sectional area than the reservoir 11b and the chamber 12a. When the diaphragm 20 'is vibrated by an actuator (not shown), the restrictor 12b is moved from the reservoir 11b to the chamber 12a. The amount of ink supplied can be adjusted.

The nozzle 42 is connected to the chamber 12a to receive ink from the chamber 12a and to eject ink. When the vibration generated by the actuator (not shown) is transmitted to the chamber 12a through the diaphragm 20 ', pressure is applied to the chamber 12a so that the nozzle 42 can eject ink by the pressure. do.

On the other hand, damper portions 11a and 32 are formed between the chamber 12a and the nozzle 42 described above. The dampers 11a and 32 may function to concentrate energy generated in the chamber 12a toward the nozzle 42 and to buffer a sudden pressure change.

In order to form the above-described components, the present embodiment proposes a method of using two silicon substrates and two glass substrates. That is, the above-mentioned components are formed by dividing the two silicon substrates and the two glass substrates, and then bonding them to manufacture an inkjet head. Hereinafter, this will be described in more detail.

First, the upper surface of the first plate 10 made of silicon is processed to correspond to the chamber 12a and the restrictor 12b (S110). In this case, as the first plate 10, as shown in FIG. 2, an SOI substrate 10 having a form in which an insulating layer 13 such as SiO 2 is interposed between silicon layers may be used. Hereinafter, a case in which an SOI substrate is used as the first plate 10 will be described as an example. However, a silicon wafer other than the SOI substrate may be used as the first plate 10.

In order to process the upper surface of the first plate 10, that is, the upper silicon layer 12 of the SOI substrate 10, a portion where the chamber 12a and the restrictor 12b are to be formed on the upper surface of the upper silicon layer 12. After arranging the selectively opened mask (not shown), a method of selectively etching the opened portion may be used.

At this time, in order to process the part where the restrictor 12b is to be formed, the process of processing the upper surface of the SOI substrate 10 may be binary. That is, after performing the primary etching as shown in FIG. 3, the etching may be performed secondarily as shown in FIG. 4 to more reliably form the region h on which the restrictor 12b is to be formed. It is.

When the chamber 12a and the like are formed using the SOI substrate 10, the insulating layer 13 positioned between the upper and lower silicon layers 11 and 12 can function as an etch stop. The depth of the chamber 12a and the like can be ensured more stably.

That is, since the depth of the chamber 12a may be determined according to the thickness of the upper silicon layer, regardless of the environment of the processing process, the upper silicon layer 12 having a thickness corresponding to the depth of the chamber 12a to be formed. By preparing the SOI substrate 10 having), it is possible to secure a stable depth of the chamber 12a regardless of various process environments.

As a method of processing the top surface of the SOI substrate 10, a dry reactive ion etching (DRIE) process, which is advantageous for vertical shape control, may be used.

After processing the upper surface of the SOI substrate 10 in this manner, as shown in Figure 5, the lower surface of the first plate 10 is processed to correspond to the damper portion (11a) and the reservoir (11b) (S120). The lower silicon layer 11 is also processed in the same manner as the first plate 10, that is, the upper surface of the SOI substrate 10 of the present embodiment.

Then, grooves are formed on one surface of the vibrating plate 20 of glass material so as to correspond to the inlet 22 (S130, FIG. 6), and after the diaphragm 20 is bonded to the upper surface of the first plate 10 (S140). 7, the other surface of the diaphragm 20 is polished (S150, FIG. 8). As a method of forming grooves in the glass diaphragm 20, a process such as sandblasting may be used, and the method of polishing the diaphragm 20 may be performed by using a chemical mechanical polishing (CMP) process. Excellent quality can be secured. In addition, by bonding the diaphragm 20 of the glass material on the first plate 10 of the silicon material, the anodic bonding between the silicon and the glass in the bonding surface between the first plate 10 and the diaphragm 20 can be implemented. It is possible to expect improved product reliability based on a firm coupling force.

Next, the second plate 30 of glass material is prepared (FIG. 9), and the second plate 30 of glass material is processed to correspond to the damper part 32 (S160 and FIG. 10). As a method of processing the second plate 30, a process such as sandblasting may be used as in the case of the diaphragm 20.

Meanwhile, as shown in FIG. 10, the damper part 32 formed on the second plate 30 may have a shape in which the width thereof is narrowed toward the direction when the nozzle plate 40 is later joined. Through such an inclined surface structure, it is possible to reduce the possibility of micro bubbles being formed at the interface between the nozzle 42 and the damper portion 32. In addition, when the inclined surface structure is formed in the damper portion 32 and the nozzle 42 is formed in the straight surface, the straightness of the ejected ink can also be ensured, and the effect of improving the printing quality can be expected. .

Next, the nozzle plate 40 made of silicon is prepared (FIG. 11), and a groove is formed in the nozzle plate 40 made of silicon so as to correspond to the nozzle 42 (S170, FIG. 12). A groove is formed in the nozzle plate 40 made of silicon in the same manner as the SOI substrate 10 described above.

Then, the nozzle plate 40 is bonded to the lower surface of the second plate 30 (S180, FIG. 13), and the other surface of the nozzle plate 40 is polished (S190, FIG. 14). By bonding the nozzle plate 40 of the silicon material to the second plate 30 of the glass material, an anodic bonding between the glass and the silicon may be realized at the bonding surface between the second plate 30 and the nozzle plate 40. As a result, the reliability of the improved product can be expected based on the firm coupling force. As a method of grinding the nozzle plate 40, a CMP process can be used as in the case of the diaphragm 20.

Then, as shown in FIG. 15, the lower surface of the first plate 10 and the upper surface of the second plate 30 are bonded (S200). By bonding the first plate 10 made of silicon material and the second plate 30 made of glass material, it is possible to implement anodic bonding between them, thereby ensuring a firm bonding force.

The inkjet head manufactured through the above process is shown in FIG. 16.

On the other hand, the bonding order between each plate presented in this embodiment is only one example, and of course, the bonding order may be changed according to design needs.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention as defined in the appended claims. It will be understood that the invention may be varied and varied without departing from the scope of the invention.

Many embodiments other than the above-described embodiments are within the scope of the claims of the present invention.

1 is a flow chart showing a method of manufacturing an inkjet head according to an embodiment of the present invention.

2 to 16 are views showing each step of the inkjet head manufacturing method according to an embodiment of the present invention.

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

10: first plate, SOI substrate 11, 12: silicon layer

11a: damper portion 11b: reservoir

12a: chamber 12b: restrictor

12c: inlet 13: insulation layer

20, 20 'diaphragm 22: inlet

30: second plate 32: damper portion

40, 40 'nozzle plate 42: nozzle

Claims (9)

A reservoir for storing ink, an inlet port through which ink is supplied to the reservoir, a chamber for receiving ink from the reservoir, a restrictor connecting the reservoir and the chamber, a nozzle for discharging ink, and an interposition between the chamber and the nozzle An inkjet head comprising a damper portion, A first plate of silicon material in which a part of the damper part, the chamber, the reservoir, and the restrictor are formed; A vibrating plate of glass material bonded to an upper surface of the first plate to cover the chamber; A second plate of glass material bonded to a lower surface of the first plate and having a portion of the damper portion formed thereon; And The inkjet head of the second plate is bonded to the bottom surface, and includes a nozzle plate of silicon material in which the nozzle is formed. The method of claim 1, A portion of the damper portion formed in the second plate has a shape in which the width thereof becomes narrow toward the nozzle plate. The method of claim 1, The first plate is an SOI substrate, A portion of the damper portion and the reservoir are formed by processing the lower surface of the SOI substrate, And the chamber and the restrictor are formed by processing an upper surface of the SOI substrate. A reservoir for storing ink, an inlet port through which ink is supplied to the reservoir, a chamber for receiving ink from the reservoir, a restrictor connecting the reservoir and the chamber, a nozzle for discharging ink, and an interposition between the chamber and the nozzle A method of manufacturing an inkjet head comprising a damper portion, Machining an upper surface of the first plate of silicon-containing material to correspond to the chamber and the restrictor; Machining a lower surface of the first plate so as to correspond to the damper portion and the reservoir; Processing a diaphragm of glass material so as to correspond to the inlet; Machining a second plate of glass material to correspond to the damper portion; Machining the nozzle plate of silicon material so as to correspond to the nozzle; Bonding the diaphragm to an upper surface of the first plate; Bonding the nozzle plate to a bottom surface of the second plate; And Bonding a lower surface of the first plate and an upper surface of the second plate. The method of claim 4, wherein A portion of the damper portion formed in the second plate has a shape in which the width thereof becomes narrow toward the nozzle plate. The method of claim 4, wherein The first plate is an ink jet head manufacturing method, characterized in that the SOI substrate. The method of claim 4, wherein Processing the diaphragm made of glass material so as to correspond to the inlet, Prior to bonding the diaphragm to an upper surface of the first plate, forming a groove corresponding to the inlet on one surface of the diaphragm; And And after the bonding of the diaphragm to the upper surface of the first plate, grinding the other surface of the vibrating plate. The method of claim 7, wherein The polishing of the other surface of the diaphragm is carried out through a chemical mechanical polishing (CMP) process. The method of claim 4, wherein Processing the nozzle plate of silicon material to correspond to the nozzle, Forming a groove corresponding to the nozzle on one surface of the nozzle plate before the bonding of the nozzle plate to the bottom surface of the second plate; And And after the bonding of the nozzle plate to the lower surface of the second plate, grinding the other surface of the nozzle plate.

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