JP4747882B2 - Surface treatment method, method for manufacturing droplet discharge head, and method for manufacturing droplet discharge device - Google Patents

Description

The present invention is a surface treatment method, a method of manufacturing a manufacturing method and a droplet discharging device of a droplet discharge head, a surface treatment method capable of performing a surface treatment of the wafer uniform, manufacturing method and a droplet of the droplet ejection heads The present invention relates to a method for manufacturing a discharge device.

  As a droplet discharge head for discharging droplets, for example, an inkjet head mounted on an inkjet recording apparatus is known. In general, this inkjet head has a nozzle substrate formed with a plurality of nozzle holes for discharging ink droplets, an ejection chamber joined to the nozzle substrate and communicating with the nozzle holes, and an ink flow path such as a reservoir. And a cavity substrate, and is configured to eject ink droplets from selected nozzle holes by applying pressure to the ejection chamber. As means for ejecting ink droplets as described above, there are an electrostatic drive system using an electrostatic actuator that utilizes electrostatic force, a piezoelectric system using a piezoelectric element, a bubble jet (registered trademark) system that uses a heating element, and the like.

  Among these, in an inkjet head using an electrostatic drive type actuator, a cavity substrate having a diaphragm at the bottom of the discharge chamber and an individual electrode facing the diaphragm through a predetermined gap (gap) are formed. It is the structure which joined the electrode glass substrate. This individual electrode is formed by sputtering ITO (Indium Tin Oxide) or the like on the bottom surface of a glass groove formed on the surface of an electrode glass substrate, for example, in order to ensure a predetermined gap length so that the diaphragm can be displaced. Is formed.

  Then, when ejecting ink droplets, a drive voltage is applied to the individual electrodes to be positively charged, and a drive voltage is applied to the corresponding diaphragm to be negatively charged. Then, the diaphragm is elastically deformed toward the individual electrode by the electrostatic attractive force generated at this time. When this drive voltage is turned off, the diaphragm is restored. At this time, the pressure inside the discharge chamber rises rapidly, and a part of the ink in the discharge chamber is discharged from the nozzle hole as an ink droplet. Such an electrostatic drive system has a feature that it consumes less power compared to a piezoelectric system using a piezoelectric element, a bubble jet (registered trademark) system using a heating element, and the like.

  In recent years, in an inkjet head using such an electrostatic drive type actuator, in order to cope with high-speed printing of a high-resolution image, the number of nozzles and the size of the inkjet head have been reduced. That is, in order to pursue high printing performance, it is required to increase the density of nozzles and discharge chambers for discharging droplets. As described above, when the actuator is densified, the partition wall constituting the discharge chamber becomes thinner as the density is increased, the rigidity of the partition wall is reduced, and crosstalk occurs due to the influence of adjacent dots. It becomes easy.

  In order to suppress the occurrence of this crosstalk, if the thickness of the cavity substrate that constitutes the diaphragm and the partition wall of the discharge chamber is reduced, handling becomes difficult, and thus a new problem that the yield is extremely lowered is caused. It was supposed to occur. In order to solve this problem, an inkjet head has been proposed, in which after the cavity substrate and the electrode glass substrate having individual electrodes are joined, the thickness of the cavity substrate is reduced and then the diaphragm and the partition wall of the discharge chamber are formed. (For example, see Patent Document 1).

  Also, in order to make the head size of the inkjet head compact, “the adhesive is discharged from the sealant injection hole opened in the electrode glass substrate through the sealant injection groove and from the sealant discharge hole. , While flowing through the sealant injection groove, each of the narrow grooves communicating with the groove was infiltrated and filled by capillary force, and an adhesive was applied from the outside to the external communication port portion of the groove. Unlike the method, an inkjet head has been proposed in which the sealing mechanism is made compact by eliminating the need for adhesive application (see, for example, Patent Document 2).

  When these are combined to increase the density of the actuator and make the head size compact, in the process of thinning the cavity substrate and the process of forming the diaphragm and the discharge chamber, the through hole of the electrode glass and the cavity A new problem has arisen that the processing liquid such as an etchant enters the actuator through the sealing agent injection groove of the substrate and the actuator cannot be driven.

  As a solution to this problem, the surface treatment jig is designed to hold a bonded substrate that is bonded to the cavity substrate and the electrode glass substrate by constantly sucking with an external vacuum pump from the suction hole inside the surface treatment jig. A semiconductor wafer etching apparatus has been proposed that uses a tool and protects the electrode glass substrate side to prevent the processing liquid from entering through the through-holes (see, for example, Patent Document 3).

Japanese Patent Laid-Open No. 11-993 (pages 4 and 4) JP 2001-3179974 (page 5 and FIG. 1) U.S. Pat. No. 6,443,440 (page 5, FIGS. 2 and 3)

  In the semiconductor wafer etching apparatus described in Patent Document 3, it is impossible to rotate the substrate in the processing solution for the purpose of improving the uniformity of etching in the wafer surface due to the presence of the tube. There is a problem that handling of the tube becomes complicated when processing the sheets. However, in order to prevent intrusion of the processing liquid from the through hole and protect the electrode glass substrate side, it is desirable to vacuum-adsorb the surface processing jig and the bonding substrate.

  For example, when attaching a bonding substrate to a surface treatment jig, the bonding substrate and the surface treatment jig are placed in a vacuum chamber, and the space formed between the bonding substrate and the surface treatment jig is gradually increased. After depressurization, the bonding substrate is adsorbed to the surface treatment jig by utilizing the fact that the space formed between the bonding substrate and the surface treatment jig is left in a depressurized state due to rapid release of air in the vacuum chamber. You can do it. Further, when removing the bonding substrate from the surface treatment jig, the pressure-reducing space may be returned to atmospheric pressure by reducing the pressure in the vacuum chamber to a pressure lower than that at the time of adsorption and then gradually releasing it to the atmosphere.

  However, when the bonding substrate is attached to and detached from the surface treatment jig in this way, the surface treatment jig has an adsorption mechanism, and thus the thickness of the surface treatment jig is inevitably increased due to the structure. That is, the number of surface treatment jigs set on the cassette carrier is limited. Therefore, the number of bonded substrates that can be subjected to surface treatment is limited, resulting in poor production efficiency.

  Further, when the surface treatment jig is set on the cassette carrier, the etched surface of the bonded substrate adsorbed by the surface treatment jig and the convex portion of the cassette carrier come into contact with each other, and the etched surface is damaged. A defect is caused on the surface of the bonded substrate. Furthermore, since the surface to be etched and the surface of the cassette carrier are close to each other, there has been a problem in that the etching solution replacement efficiency on the surface to be etched is reduced or fluctuated and the etching rate varies.

The present invention has been made to solve the above problems, a surface treatment method capable of performing surface treatment of a substrate which is held by suction by the surface treatment apparatus uniform, the method for manufacturing the droplet-discharging head And a method of manufacturing a droplet discharge device.

The surface treatment method according to the present invention includes a step of placing a substrate to be surface-treated on a surface treatment jig having a concave portion formed on a side surface, storing the substrate in a decompression chamber, and holding the substrate on the surface treatment jig. And a step of fitting the surface treatment jig holding the substrate by suction into the cassette carrier by fitting the concave portion formed on the side surface thereof into the convex portion formed by projecting to the inside of the cassette carrier, and the cassette And dipping the carrier in a surface treatment liquid and subjecting the substrate to a surface treatment. Therefore, the substrate can be sucked and held on the surface treatment jig without requiring a special sucking mechanism, complicated procedure, or operation.

In the method for manufacturing a droplet discharge head according to the present invention, an electrode in which a silicon substrate and an individual electrode for driving a vibration plate formed on the silicon substrate are formed on a surface treatment jig in which a concave portion is formed on a side surface. Placing a glass substrate and a bonding substrate bonded with a gap between one side of the silicon substrate and the individual electrodes , storing the bonding substrate in a decompression chamber, and sucking and holding the bonding substrate on a surface treatment jig; A step of setting the surface treatment jig holding and holding the bonding substrate on the cassette carrier, and immersing the cassette carrier in an etching solution and applying a surface treatment to the silicon substrate of the bonding substrate to form a flow path in the silicon substrate. And a step of forming a cavity substrate. Accordingly, since the surface treatment liquid such as an etchant is uniformly replaced over the entire surface to be etched of the silicon substrate, stable etching can be realized at a uniform etching rate.

  A method for manufacturing a droplet discharge device according to the present invention includes the method for manufacturing the droplet discharge head described above. Therefore, the same effect as the above-described method for manufacturing a droplet discharge head is obtained.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing a state in which a surface treatment jig 50 according to an embodiment of the present invention is set on a cassette carrier 70. FIG. 2 is a plan view showing a state in which the surface treatment jig 50 is set on the cassette carrier 70. FIG. 3 is an explanatory diagram for explaining the distribution of the etching amount of the wafer. Based on FIGS. 1-3, the structure of the surface treatment jig | tool 50 is demonstrated. In addition, the case where one side of the wafer 60 is attracted to the surface treatment jig 50 is shown as an example.

  The surface treatment jig 50 is configured to have a size capable of attracting the wafer 60. Further, the surface treatment jig 50 is formed with a recess 51 so as to be fitted into a protrusion 71 formed to protrude inside the cassette carrier 70. Here, a case where the surface treatment jig 50 is an octagonal column is shown as an example, but the present invention is not limited to this. For example, the surface treatment jig 50 may be of a size that allows the wafer 60 to be placed thereon and can form a recess 51 that can be fitted to the protrusion of the cassette carrier 70. The case where the wafer 60 is a bonded substrate obtained by bonding the cavity substrate 20 and the electrode glass substrate 30 will be described as an example.

  The conventional surface treatment jig has no concave portion formed on the side surface, and is set between the convex portions formed on the inside of the cassette carrier. That is, when the surface treatment jig is set on the cassette carrier, the etched surface of the wafer held by the surface treatment jig and the convex portion of the cassette carrier come into contact with each other, and the wafer etched surface is damaged. This gave a defect on the wafer surface.

  In addition, since the wafer etching surface and the convex portion of the cassette carrier are close to each other, the etching solution replacement efficiency on the wafer etching surface is reduced or fluctuated, resulting in variations in the etching rate. . That is, as shown by A in FIG. 3, the portion where the wafer to be etched and the convex portion of the cassette carrier come into contact with each other is not etched, and the portion where the wafer to be etched and the convex portion of the cassette carrier do not come into contact with each other. It was supposed to be etched.

  The surface treatment jig 50 according to this embodiment has a concave portion 51 formed on its side surface, and the concave portion 51 is combined with the convex portion 71 of the cassette carrier 70. Therefore, as shown in FIG. 2, the surface to be etched of the wafer 60 and the convex portion 71 of the cassette carrier 70 do not come into contact with each other. Further, since the concave portion 51 of the surface treatment jig 50 and the convex portion 71 of the cassette carrier 70 are fitted to each other, the surface treatment jig 50 can be easily and reliably set on the cassette carrier 70. It is.

  That is, since the surface to be etched of the wafer 60 and the convex portion 71 of the cassette carrier 70 do not come into contact with each other, the surface to be etched of the wafer 60 is not damaged by the contact, and the surface of the wafer 60 to be etched has surface defects. Surface treatment (wet etching) can be realized in such a way that it does not occur. Further, as shown by B in FIG. 3, the surface to be etched of the wafer 60 and the convex portion 71 of the cassette carrier 70 do not come into contact with each other, so that the surface treatment liquid such as an etchant is uniform over the entire surface to be etched of the wafer 60. Therefore, a stable surface treatment can be realized on the entire wafer 60 at a uniform etching rate.

  The surface treatment jig 50 is preferably formed of a material having excellent chemical resistance. Then, etching with a wide selection range of the liquid (etchant) used for etching can be realized. Examples of such materials having excellent chemical resistance include PTFE (polytetrafluoroethylene), PFA (tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer), and FEP (tetrafluoroethylene / hexafluoropropylene copolymer). Fluorine resin such as coalescence).

  Next, attachment / detachment of the wafer 60 to / from the surface processing jig 50 will be described. FIG. 4 is an explanatory diagram for explaining attachment of the wafer 60 to the surface treatment jig 50. FIG. 5 is an explanatory diagram for explaining the removal of the wafer 60 from the surface treatment jig 50. First, a case where the wafer 60 is attached to the surface treatment jig 50 will be described with reference to FIG. Then, a case where the wafer 60 is removed from the surface treatment jig 50 will be described with reference to FIG.

  First, the case where the wafer 60 is attached to the surface treatment jig 50 will be described. On the contact surface of the surface treatment jig 50 with the wafer 60, a suction portion 52 is formed with a predetermined depth to suck and hold the wafer 60. The suction portion 52 is provided with an O-ring 56. The O-ring 56 is for forming a closed space that keeps the surface treatment jig 50 and the wafer 60 airtight. The O-ring 56 only needs to be formed smaller than the outer diameter of the wafer 60.

  Further, the O-ring 56 may be attached to the surface treatment jig 50 from the beginning, or may be attached when holding the wafer 60 by suction. The O-ring 56 is not particularly limited as long as it has chemical resistance and elasticity. For example, the O-ring 56 may be formed of fluorine rubber or the like. The O-ring 56 preferably has a diameter equal to or smaller than the depth of the suction portion 52 formed in the surface treatment jig 50.

  When the wafer 60 is attached to the surface treatment jig 50, the wafer 60 is placed on the surface treatment jig 50 and the suction auxiliary jig 55 is placed on the wafer 60 as shown in FIG. Thus, the wafer 60 and the O-ring 56 are brought into contact with each other. The suction assisting jig 55 serves to press the wafer 60 against the O-ring 56 by applying a load to the wafer 60. Accordingly, the suction assisting jig 55 optimizes the weight of the suction assisting jig 55 so that the wafer 60 and the entire O-ring 56 of the surface treatment jig 50 are in contact with each other, and controls the load for pressing the wafer 60. There is a need to.

  That is, if the suction assisting jig 55 is too light, the wafer 60 and the entire O-ring 56 of the surface treatment jig 50 do not come into contact with each other, so that the wafer 60 cannot be sufficiently sucked. On the other hand, if the suction assisting jig 55 is too heavy, the O-ring 56 of the wafer 60 and the surface treatment jig 50 will be in close contact with each other, and there is sufficient closed space between the wafer 60 and the surface treatment jig 50. Will not be decompressed. Therefore, the suction assisting jig 55 is required to set a weight capable of sufficiently sucking and holding the wafer 60 on the surface processing jig 50.

  Note that the suction assisting jig 55 need not be used as long as it is pressed against the O-ring 56 by the weight of the wafer 60 itself. However, since the wafer 60 is warped, the wafer 60 is not completely flat. Therefore, it is desirable to use the suction assisting jig 55 whose weight is optimized so as to control the load, so that the wafer 60 is pressed against the surface processing jig 50. Then, the wafer 60 can be sufficiently sucked and held on the surface treatment jig 50.

  Next, the wafer 60 on which the suction assisting jig 55 is placed and the surface treatment jig 50 are placed in the vacuum chamber 80. The vacuum chamber 80 may be of a size that can accommodate the wafer 60 on which the suction assisting jig 55 is placed and the surface processing jig 50, and the material and type thereof are not particularly limited. A vacuum pump 81 is connected to the vacuum chamber 80. The vacuum pump 81 allows the inside of the vacuum chamber 80 to be evacuated.

  When the wafer 60 on which the suction auxiliary jig 55 is placed and the surface treatment jig 50 are accommodated in the vacuum chamber 80, the pressure is slowly reduced by a vacuum pump (FIG. 4A). As a result, the closed space formed between the wafer 60 and the surface treatment jig 50 is gradually decompressed. Thereafter, the vacuum chamber 80 is suddenly opened to the atmosphere (FIG. 4B). By doing so, the closed space formed between the wafer 60 and the surface treatment jig 50 is left in a decompressed state. Using this principle, the wafer 60 is vacuum-sucked to the surface processing jig 50.

  Next, a case where the wafer 60 is removed from the surface processing jig 50 will be described. After performing predetermined processing on the wafer 60 (after forming the discharge chamber 21 and the reservoir 23 on the cavity substrate 20), the surface treatment jig 50 on which the wafer 60 is sucked and held is placed in the vacuum chamber 80. Then, the inside of the vacuum chamber 80 is depressurized by a vacuum pump. When this reduced pressure reaches a lower pressure than when the wafer 60 is sucked, a force is applied to the wafer 60 from the outside in the direction opposite to the suction assisting jig 50. Then, the wafer 60 is lifted, and the closed space between the wafer 60 and the surface treatment jig 50 is opened (FIG. 5A). At this time, the entire inside of the vacuum chamber 80 is in a vacuum state.

  In this state, the vacuum chamber 80 is opened to the atmosphere (FIG. 5B). Then, the closed space formed between the wafer 60 and the surface treatment jig 50 can be returned to the same pressure as the atmospheric pressure. In this way, the wafer 60 is removed from the surface treatment jig 50. Therefore, by placing the wafer 60 and the surface treatment jig 50 in the vacuum chamber 80, the wafer 60 can be vacuum-sucked to the surface treatment jig 50. It is not necessary to provide a mechanism, and handling is easy.

  Further, when a sealing agent injection hole is formed in the electrode glass substrate 30 and the sealing agent is filled there from, an electrode glass is prevented from entering a processing liquid such as an etchant from the sealing agent injection hole. The wafer 50 can be attached to or detached from the surface treatment jig 50 while protecting the substrate 30. Therefore, when attaching / detaching the wafer 60 to / from the surface processing jig 50, complicated procedures and operations are not required, and the processing liquid is prevented from entering the actuator, and the head size of the inkjet head is increased. It becomes possible.

  FIG. 6 is an exploded perspective view of the droplet discharge head 100 assembled using the surface treatment jig 50. FIG. 7 is a cross-sectional view illustrating a schematic configuration in a state where the droplet discharge head 100 is assembled. The configuration and operation of the droplet discharge head 100 will be described with reference to FIGS. In the embodiment, as a representative of a device equipped with an electrostatic actuator that is driven by an electrostatic drive method, a face ejection type droplet discharge head that discharges droplets from nozzle holes provided on the surface side of the nozzle substrate. Is described as an example.

  In this embodiment, a case of a face eject type droplet discharge head will be described as an example, but the present invention is not limited to this. For example, a side eject type droplet discharge head that discharges droplets from nozzle holes provided on the side surface of the nozzle substrate or cavity substrate may be used. Moreover, in the following drawings including FIG. 6, the relationship of the size of each component may be different from the actual one.

  As shown in FIG. 6, this droplet discharge head 100 is characterized by a three-layer structure in which three substrates of a nozzle substrate 10, a cavity substrate 20, and an electrode glass substrate 30 are joined in order. The nozzle substrate 10 is bonded to one surface (upper surface) of the cavity substrate 20, and the electrode glass substrate 30 is bonded to the other surface (lower surface). That is, the cavity substrate 20 is sandwiched between the electrode glass substrate 30 and the nozzle substrate 10 from above and below.

  In this embodiment, the electrode glass substrate 30 and the cavity substrate 20 are bonded by anodic bonding (the anodic bonding is described in FIG. 8), and the cavity substrate 20 and the nozzle substrate 10 are epoxy resin. It demonstrates as what joins using adhesive agents, such as. The individual electrodes 31 formed on the electrode glass substrate 30 of the droplet discharge head 100 are supplied with a drive signal (pulse voltage) by a power supply means such as a driver IC (not shown).

[Electrode glass substrate 30]
The electrode glass substrate 30 is preferably formed of, for example, glass such as borosilicate glass having a thickness of 1 mm as a main material. Here, a case where the electrode glass substrate 30 is formed of borosilicate glass is shown as an example, but the electrode glass substrate 30 may be formed of single crystal silicon. On the surface of the electrode glass substrate 30, a plurality of glass grooves 32 are formed in a thickness of 0.3 μm (micrometer), for example, in accordance with the shape of the discharge chamber 21 of the cavity substrate 20 described later.

  In addition, inside the glass groove 32 (particularly at the bottom), the individual electrodes 31 serving as fixed electrodes are formed so as to face the respective discharge chambers 21 (vibrating plates 22) of the cavity substrate 20 with a certain interval. Has been. And this glass groove | channel 32 is pattern-formed by the slightly large shape similar to these shapes so that the one part can mount | wear with the individual electrode 31. FIG. The individual electrode 31 may be produced by sputtering ITO (Indium Tin Oxide) with a thickness of 0.1 μm, for example.

  The individual electrode 31 is formed with a lead portion 33 and a terminal portion 34. The individual electrode 31 is connected to power supply means such as an FPC (Flexible Print Circuit) (not shown) at the terminal portion 34, and a drive signal is supplied to the individual electrode 31 from the power supply means. Yes. The lead portion 33 is a portion that connects the individual electrode 31 and the terminal portion 34. In addition, when it is not necessary to distinguish in particular, the lead part 33 and the terminal part 34 will be described together as the individual electrode 31. A portion where the power supply means and the terminal portion 34 are connected is referred to as a connection portion 35.

  The electrode glass substrate 30 is provided with an ink supply hole 25 serving as a flow path for taking in liquid supplied from an external ink tank (not shown). The ink supply hole 25 communicates with the ink supply hole 25 formed in the cavity substrate 20 so as to supply ink to the reservoir 23. Further, a sealing agent injection hole for filling the sealing agent 40 may be formed in the electrode glass substrate 30. The sealant 40 is preferably, for example, an epoxy resin.

  The sealing agent 40 is for sealing a gap formed between the individual electrode 31 and the diaphragm 22 so that a processing liquid such as an etchant does not enter the gap. FIG. 6 shows two electrode rows extending in the short side direction of the individual electrode 31. In addition, when the short side of the individual electrode 31 is formed obliquely with respect to the long side and the individual electrode 31 has an elongated parallelogram shape, an electrode array extending in a direction perpendicular to the long side direction is formed. What should I do?

[Cavity substrate 20]
The cavity substrate 20 is configured using, for example, a silicon single crystal substrate (hereinafter simply referred to as a silicon substrate) having a thickness of about 50 μm as a main material. In the cavity substrate 20, a plurality of discharge chambers (or pressure chambers) 21 whose bottom wall is the vibration plate 22 are formed. The discharge chamber 21 is formed corresponding to the electrode row of the individual electrode 31. The cavity substrate 20 is formed with a reservoir 23 for supplying droplets to the respective discharge chambers 21.

On the lower surface of the cavity substrate 20 (the surface facing the electrode glass substrate 30), a TEOS film (herein, tetraethylsilane: tetraethoxysilane) An insulating film (not shown) made of an SiO ₂ film made of ethyl silicate) is formed to a thickness of 0.1 μm using a plasma CVD (also referred to as Chemical Vapor Deposition: TEOS-pCVD) method. This is for preventing dielectric breakdown and short-circuit when the diaphragm 22 is driven, and for preventing etching of the cavity substrate 20 by droplets of ink or the like.

Although the case where the insulating film is a TEOS film is shown here, the present invention is not limited to this, and any material that improves the insulating performance may be used. For example, Al ₂ O ₃ (aluminum oxide (alumina)) may be used. The cavity substrate 20 is also provided with ink supply holes 25 (in communication with the ink supply holes 25 provided in the electrode glass substrate 30). Furthermore, a common electrode terminal 27 is provided as a terminal for supplying charges having the opposite polarity to the individual electrode 31 from the power supply means to the diaphragm 22.

The diaphragm 22 may be formed of a high concentration boron doped layer. The etching rate in etching single crystal silicon with an alkaline solution such as an aqueous potassium hydroxide solution is very small in a high concentration region of about 5 × 10 ¹⁹ atoms / cm ³ or more when the dopant is boron. For this reason, when the diaphragm 22 is formed as a high-concentration boron-doped layer and the discharge chamber 21 is formed by anisotropic etching with an alkaline solution, the boron-doped layer is exposed and the etching rate becomes extremely small, so-called etching stop. By using the technique, the diaphragm 22 can be formed in a desired thickness.

[Nozzle substrate 10]
The nozzle substrate 10 is composed of, for example, a silicon substrate having a thickness of about 100 μm as a main material. And it is joined to the upper surface of the cavity substrate 20 (the surface opposite to the surface to which the electrode glass substrate 30 is joined). The nozzle substrate 10 has a plurality of nozzle holes 11 communicating with the discharge chamber 21. Each nozzle hole 11 discharges the liquid droplets transferred from the discharge chamber 21 to the outside. In addition, when the nozzle hole 11 is formed in a plurality of stages (for example, two stages), the straightness at the time of discharging a droplet can be improved.

  Here, the nozzle substrate 10 having the nozzle holes 11 is described as the upper surface, and the electrode glass substrate 30 is described as the lower surface. However, when actually used, the nozzle substrate 10 is lower than the electrode glass substrate 30. There are many. In addition, the nozzle substrate 10 is formed with an orifice 12 that communicates a discharge chamber 21 formed in the cavity substrate 20 and a reservoir 23. Further, a diaphragm 13 for buffering the pressure applied to the liquid on the reservoir 23 side by the diaphragm 22 is formed on the nozzle substrate 10. The orifice 12 may be formed in the cavity substrate 20 instead of the nozzle substrate 10.

  Here, the operation of the droplet discharge head 100 will be briefly described. The reservoir 23 is supplied with droplets of ink or the like from the outside through the ink supply hole 25. In addition, droplets are supplied to the discharge chamber 21 from the reservoir 23 via the orifice 24. A pulse voltage of about 0 V to 40 V is applied to the individual electrode 31 selected by a transmission circuit (not shown) such as a driver IC, and the individual electrode 31 is positively charged.

  At this time, charge having a negative polarity is supplied to the cavity substrate 20 through the common electrode terminal 27, and the diaphragm 22 corresponding to the positively charged individual electrode 31 is relatively negatively charged. Therefore, an electrostatic force is generated between the selected individual electrode 31 and the diaphragm 22. If it does so, the diaphragm 22 will be drawn near to the individual electrode 31 side by electrostatic force, and will bend.

  Thereafter, when the supply of electric charges to the individual electrode 31 is stopped, the electrostatic force between the diaphragm 22 and the individual electrode 31 disappears, and the diaphragm 22 is restored to the original state by the elastic force. At this time, since the volume of the discharge chamber 21 is rapidly decreased, the pressure inside the discharge chamber 21 is rapidly increased. Thereby, a part of the ink in the discharge chamber 21 is discharged from the nozzle hole 11 as an ink droplet. For example, printing is performed by the droplets landing on a recording sheet, for example. Thereafter, the droplets are replenished from the reservoir 23 into the discharge chamber 21 through the supply port 32, and the initial state is restored.

  FIG. 8 is an explanatory view showing an anodic bonding method. Based on FIG. 8, a wafer 60 that is a bonded substrate manufactured by anodic bonding of the electrode glass substrate 30 and the cavity substrate 20 will be described. In general, anodic bonding is performed by aligning a cavity substrate 20 made of a silicon substrate and an electrode glass substrate 30 and then pressing the two substrates between a metal plate in contact with the cavity substrate 20 and a metal plate in contact with the electrode glass substrate 30. It is done.

  A positive electrode is connected to the metal plate in contact with the cavity substrate 20, and a negative electrode is connected to the metal plate in contact with the electrode glass substrate 30 to apply a voltage of 800V. Then, the metal plate is brought into direct contact with the cavity substrate 20, and the cavity substrate 20 and the electrode glass substrate 30 are brought into contact with the electrode substrate formed on the electrode glass substrate 30 of each head chip and the cavity substrate 20 with an equipotential contact. An equipotential with the electrode part formed on the substrate is ensured.

  Thus, the cavity substrate 20 and the electrode glass substrate 30 are bonded together to form a wafer 60 that is a bonded substrate. Then, as described with reference to FIGS. 4 and 5, the wafer 60 is vacuum-sucked by the surface treatment jig 50 and proceeds to the subsequent manufacturing process. That is, the surface to be etched of the wafer 60 is a surface on which liquid flow paths such as the discharge chamber 21 and the reservoir 23 of the cavity substrate 20 are formed, and is a portion that requires high processing accuracy by etching.

  Therefore, if the etching varies or the substrate surface is damaged, the processing accuracy becomes low and the electrostatic actuator does not have a function. Therefore, in the present embodiment, after the cavity substrate 20 and the electrode glass substrate 30 are anodically bonded, the wafer 60 is sucked and held on the surface treatment jig 50 so that the subsequent manufacturing process proceeds. It is. The surface treatment jig 50 can cope with various treatment liquids such as various etchants because of its high chemical resistance.

  FIG. 9 is a perspective view showing an example of a droplet discharge device 150 on which the droplet discharge head 100 is mounted. A droplet discharge device 150 shown in FIG. 9 is a general inkjet printer. The droplet discharge device 150 can be manufactured by a known manufacturing method. The droplet discharge head 100 obtained in the embodiment has high processing accuracy of the cavity substrate 20 because the wafer 60 is sucked and held on the surface processing jig 50 and then subjected to processing such as etching. is there.

  In addition to the droplet discharge device 150 shown in FIG. 9, the droplet discharge head 100 obtained in the embodiment can be used to manufacture liquid crystal display color filters and an organic EL display device by variously changing the droplets. The present invention can also be applied to the formation of the light-emitting portion, the discharge of biological fluid, and the like. Further, the surface treatment jig 50, the surface treatment method, the droplet discharge head 100, and the droplet discharge device 150 according to the embodiment of the present invention are not limited to the contents described in the above-described embodiment. These can be changed within the scope of the idea of the present invention.

  Although the case where the droplet discharge head 100 according to the embodiment has a three-layer structure including the electrode glass substrate 30, the cavity substrate 20, and the nozzle substrate 10 has been described as an example, the present invention is not limited to this. For example, the droplet discharge head may have a four-layer structure including an electrode glass substrate, a cavity substrate, a reservoir substrate, and a nozzle substrate. Further, in the embodiment, the case where the cavity substrate 20 and the electrode glass substrate 30 are bonded by anodic bonding to form the wafer 60 has been described as an example, but the present invention is not limited to this, and a bonding method other than anodic bonding is used. A wafer 60 may be formed.

  In the embodiment, the case where the wafer 60 is formed by bonding the cavity substrate 20 and the electrode glass substrate 30 has been described as an example. However, the present invention is not limited to this. For example, the wafer 60 may be a substrate that can be sucked and held by the surface treatment jig 50 and may not be a bonded substrate obtained by bonding a plurality of substrates. In the embodiments, the case where the surface to be etched of the wafer 60 is subjected to surface treatment by etching has been described as an example. However, the present invention is not limited to this, and any method may be used as long as one surface of the wafer 60 is subjected to surface treatment.

It is a perspective view which shows the setting method to the cassette carrier of the jig for surface treatment. It is a top view which shows the set state to the cassette carrier of the jig for surface treatment. It is explanatory drawing for demonstrating distribution of the etching amount of a wafer. It is explanatory drawing for demonstrating the attachment to the jig | tool for surface treatment of a wafer. It is explanatory drawing for demonstrating the removal from the jig | tool for surface treatment of a wafer. It is a disassembled perspective view of a droplet discharge head. It is sectional drawing which shows schematic structure of the state by which the droplet discharge head was assembled. It is explanatory drawing which shows the anodic bonding method. It is the perspective view which showed an example of the droplet discharge apparatus carrying a droplet discharge head.

Explanation of symbols

10 Nozzle Substrate, 11 Nozzle Hole, 12 Orifice, 13 Diaphragm, 20 Cavity Substrate, 21 Discharge Chamber, 22 Vibration Plate, 23 Reservoir, 25 Ink Supply Hole, 27 Common Electrode Terminal, 30 Electrode Glass Substrate, 31 Individual Electrode, 32 Glass Groove, 33 Lead part, 34 Terminal part, 35 Connection part, 40 Sealant, 50 Surface treatment jig, 51 Recess, 52 Adsorption part, 55 Adsorption jig, 56 O-ring, 60 Wafer, 70 Cassette carrier , 71 convex portion, 80 vacuum chamber, 81 vacuum pump, 100 droplet discharge head, 150 droplet discharge device.

Claims (3)

Placing a substrate to be surface-treated on a surface treatment jig having a recess formed on a side surface, storing the substrate in a decompression chamber, and sucking and holding the substrate on the surface treatment jig;
A step of fitting the surface treatment jig holding the substrate by suction with a concave portion formed on a side surface of the jig and projecting the convex portion formed inside the cassette carrier, and setting the cassette carrier on the cassette carrier;
A step of immersing the cassette carrier in a surface treatment liquid and subjecting the substrate to a surface treatment. A surface treatment jig having a recess formed on a side surface , a silicon substrate, and an electrode glass substrate on which an individual electrode for driving a vibration plate formed on the silicon substrate is formed. Placing a bonded substrate bonded with a gap between the individual electrodes , storing the bonded substrate in a decompression chamber, and holding the bonded substrate on the surface treatment jig;
A step of setting the surface treatment jig holding the bonded substrate on a cassette carrier;
Immersing said cassette carrier in an etching solution, a droplet discharge, characterized in that and a step of the cavity substrate by forming a flow path on the silicon substrate by performing a surface treatment on the silicon substrate of the bonded substrate Manufacturing method of the head. A method for manufacturing a droplet discharge device, comprising the method for manufacturing a droplet discharge head according to claim 2 .

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