JP2015012010A - Apparatus for manufacturing thin film, electromechanical conversion element, liquid discharge head and ink jet recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus for manufacturing thin film capable of suppressing occurrence of clogging at a nozzle opening to maintain good discharge in discharge of a functional ink that is likely to react with moisture in an atmosphere.SOLUTION: An apparatus for manufacturing thin film at least comprises: a stage for holding a substrate; a liquid discharge head 208 which is arranged opposite to the stage and discharges a functional ink having reactivity with water from a nozzle in an ink jet method to apply the functional ink onto the substrate; and a cap member 60 for capping a discharge surface 208a of the liquid discharge head 208, in which humidity of an atmosphere in the inside 60a of the cap member sealed by capping is adjusted.

Description

The present invention relates to a thin film manufacturing apparatus for manufacturing a thin film such as an electromechanical conversion film, an electromechanical conversion element including an electromechanical conversion film manufactured by the thin film manufacturing apparatus, and a liquid discharge head including the electromechanical conversion element And an ink jet recording apparatus.
About.

2. Description of the Related Art An ink jet recording apparatus used as an image forming apparatus such as a printer, a facsimile machine, and a copying apparatus includes a liquid ejection head (hereinafter also referred to as “ink jet head”) that ejects liquid droplets (ink droplets) onto an object to be coated.
The liquid ejection head includes a nozzle that ejects ink droplets, a pressure chamber (also referred to as an ink flow path, a pressure liquid chamber, a pressure chamber, a discharge chamber, and a liquid chamber) that communicates with the nozzle, and a pressure chamber. Energy generated by the energy generation means, comprising: an electromechanical conversion element such as a piezoelectric element that pressurizes the ink, or an electrothermal conversion element such as a heater; a diaphragm that forms a wall surface of the ink flow path; and an energy generation means. As a result, an ink droplet is ejected from a nozzle by pressurizing ink in a pressurizing chamber.

  If the droplet discharge head is left in the air during standby of the ink jet recording apparatus or the like, the ink solvent evaporates over time, so that the ink dries and the ink viscosity near the nozzle holes increases and the ink is discharged. It may become difficult to be discharged. A method for preventing such a discharge failure has been proposed (see, for example, Patent Documents 1 and 2).

  Patent Document 1 includes a capping unit that seals a nozzle forming surface of a jet type recording head, and receives a negative pressure from a negative pressure generating unit to suck and discharge ink from the nozzle opening. Is a taper-shaped space having an inclined surface that continuously shrinks from the opening that seals the nozzle formation surface of the recording head toward the ink discharge port and guides the ink in the capping unit toward the discharge port. There is described an ink jet recording apparatus in which a liquid holding means capable of holding a liquid by a capillary action is applied to a pipe line formed and communicated from an ink discharge port to a negative pressure generating means.

  On the other hand, in Patent Document 2, even when the nozzle opening of the droplet discharge head is still sealed by the capping device, clogging of the nozzle opening and the like is enabled by allowing the moisturizing liquid to be supplied into the sealing portion. In order to prevent this, an absorbent material is provided in the sealing part, and a first communication pipe and a second communication pipe that penetrate the sealing part and the absorbent material are provided, and the first communication pipe is provided. An ink jet recording apparatus is described in which a first pump for decompressing the space is connected, and a second pump for supplying moisturizing liquid to the interior of the space is connected to the second communication pipe.

  By the way, in the sol-gel method known as one of methods for producing ceramics or the like, a method of applying a precursor solution by an ink jet method has been proposed. For example, a technique is known in which a functional ink (for example, PZT precursor) is dropped onto a thin electromechanical conversion film constituting an electromechanical conversion element of an inkjet head by an inkjet method to form a predetermined pattern ( For example, see Patent Document 3).

  In Patent Document 3, an electromechanical conversion film is formed on a first electrode formed on a substrate by an ink jet method, and a second electrode is formed on the electromechanical conversion film. A sol-gel method is used in the forming process, and a technique for applying the precursor liquid by inkjet is disclosed.

A functional ink such as a precursor sol-gel ink used in the sol-gel method may react with moisture in the atmosphere to cause a hydrolysis / polycondensation reaction and stick to the nozzle opening.
That is, the precursor liquid filled in the liquid discharge head of the thin film manufacturing apparatus adheres not only to the volatilization of the solvent at the nozzle opening but also to the reaction with water in the atmosphere during the rest or standby of the apparatus, and clogs the nozzle. Therefore, there is a problem that it is difficult to obtain the effect of preventing the occurrence of defective discharge only by preventing the drying from the nozzle opening by the methods described in Patent Documents 1 and 2.

  In a device that discharges functional ink such as sol-gel precursor liquid (PZT precursor) by an inkjet method to form an electromechanical conversion film, it prevents clogging due to ink sticking at the nozzle opening of the liquid discharge head, and is good There is a need for a technique that can maintain accurate discharge.

  Therefore, in view of the above problems, the present invention provides a thin film manufacturing apparatus capable of preventing clogging at a nozzle opening and maintaining good discharge in discharging functional ink that easily reacts with moisture in the atmosphere. For the purpose.

  In order to solve the above-described problems, a thin film manufacturing apparatus according to the present invention discharges a functional ink that is disposed opposite to a stage that holds a substrate and has water and reactivity from the nozzle by an inkjet method. At least a liquid discharge head to be coated on the substrate and a cap member for capping the discharge surface of the liquid discharge head, wherein the humidity of the atmosphere inside the cap member sealed by capping is adjusted. It is a thin film manufacturing apparatus.

  According to the present invention, it is possible to provide a thin film manufacturing apparatus capable of preventing clogging at a nozzle opening and maintaining good discharge in discharging functional ink that easily reacts with moisture in the atmosphere.

It is a cross-sectional schematic diagram which shows an example of the capping means with which the thin film manufacturing apparatus of this embodiment is provided. It is a cross-sectional schematic diagram which shows an example of the capping means with which the thin film manufacturing apparatus of this embodiment is provided. It is a cross-sectional schematic diagram which shows an example of the capping means with which the thin film manufacturing apparatus of this embodiment is provided. It is a flowchart which shows an example of the synthesis | combining method of the functional ink (precursor liquid) which is a material of an electromechanical conversion film. It is explanatory drawing which shows an example of the formation method of an electromechanical conversion element. It is a perspective view which shows an example of the thin film manufacturing apparatus of this embodiment. It is explanatory drawing which shows an example of the formation method of an electromechanical conversion element. It is a cross-sectional schematic diagram which shows an example of the liquid discharge head concerning this embodiment. It is a cross-sectional schematic diagram which shows an example of the liquid discharge head concerning this embodiment. It is a schematic diagram which shows an example of the inkjet printer which is an inkjet recording device concerning this embodiment. It is sectional drawing which shows an example of the inkjet printer which is an inkjet recording device concerning this embodiment. It is a perspective view which shows an example of the deflection | deviation mirror of this embodiment. It is a cross-sectional schematic diagram which shows an example of the acceleration sensor of this embodiment. It is a perspective view which shows an example of the head position adjustment means of HDD of this embodiment. It is a cross-sectional schematic diagram which shows an example of the piezoelectric power generation element of this embodiment. It is a cross-sectional schematic diagram which shows an example of the ferroelectric memory of this embodiment. It is a perspective view which shows an example of the angular velocity sensor of this embodiment. It is a cross-sectional schematic diagram which shows an example of the micropump of this embodiment. It is a cross-sectional schematic diagram which shows an example of the microvalve of this embodiment.

  Hereinafter, a thin film manufacturing apparatus, an electromechanical conversion element, a liquid discharge head, and an ink jet recording apparatus according to the present invention will be described with reference to the drawings. It should be noted that the present invention is not limited to the embodiments of the examples shown below, and other embodiments, additions, modifications, deletions, and the like can be changed within a range that can be conceived by those skilled in the art. Any aspect is included in the scope of the present invention as long as the operations and effects of the present invention are exhibited.

[Thin film manufacturing equipment]
The thin film manufacturing apparatus according to the present embodiment is disposed on a stage that holds a substrate and a functional ink that is disposed opposite to the stage and has reactivity with water from a nozzle by an inkjet method. At least a liquid discharge head and a cap member for capping the discharge surface of the liquid discharge head are provided, and the humidity of the atmosphere inside the cap member sealed by capping is adjusted.

The stage and / or the liquid discharge head is relatively moved to discharge the functional ink onto the substrate and apply in an arbitrary pattern, and the functional ink on the substrate is heated and crystallized. And a heating mechanism unit that is a functional thin film.
In addition, as a means for heating the functional ink in the heating mechanism section, a heating means such as a hot plate, an oven, a halogen lamp, a xenon lamp, an infrared lamp, or a laser irradiation means such as a YAG laser, a CO ₂ laser, an Ar laser, etc. Is used.
Since the thin film manufacturing apparatus of the present invention is characterized by the liquid discharge application mechanism unit, the liquid discharge application mechanism unit will be described below.

FIG. 6 is a perspective view illustrating a configuration example of a liquid discharge coating mechanism used in the thin film manufacturing apparatus.
As shown in FIG. 6, the liquid discharge application mechanism is a so-called inkjet coating apparatus, which is a base 200 as a base of the apparatus, and is installed on the base 200, and a Y-axis drive that moves the stage 203 in the Y-axis direction. Means 201, a stage 203 which is installed on the Y-axis driving means 201 and holds the substrate 202 thereon, and is disposed opposite to the stage 203 and ejects functional ink (inkjet head). ) 208, a Z-axis drive unit 211 that supports the liquid discharge head 208 via the head base 206 and moves it in the Z-axis direction, and supports the liquid discharge head 208, the head base 206, and the Z-axis drive unit 211 to support X. An X-axis drive unit 205 that moves in the axial direction, an X-axis support member 204 that supports the X-axis drive unit 205, and head maintenance And a Nsu means 209.

  Here, as shown in FIG. 8, the liquid discharge head 208 includes a vibration plate 30, an electromechanical transducer 40 that is a piezoelectric element provided on the vibration plate 30, and a pressure chamber (filled with functional ink). 21) and a nozzle plate 10 provided with nozzles 11 serving as droplet discharge holes for discharging functional ink corresponding to the pressure chambers 21.

The pressure chamber 21 is a space surrounded by the diaphragm 30, the wall surface (partition wall portion) of the pressure chamber substrate 20, and the nozzle plate 10.
An electromechanical conversion element 40 is formed on the surface of the diaphragm 30 opposite to the pressure chamber 21. The plate surface of the pressure chamber 21 facing the diaphragm 30 is the nozzle plate 10.

  In the ink jet head 208 configured as described above, the nozzle 11 to be ejected by the oscillation circuit based on predetermined pattern data from a control unit (not shown) in a state where the functional ink is filled in each pressure chamber 21. A pulse voltage is applied to the upper electrode 44 corresponding to. By applying this voltage pulse, the electromechanical conversion film 43 is contracted in the direction parallel to the vibration plate 30 by the piezoelectric effect so that the vibration plate 30 becomes convex toward the pressure chamber 21 side. Will be bent. As a result, the pressure in the pressure chamber 21 is rapidly increased, and the functional ink is ejected from the nozzle 11 communicating with the pressure chamber 21. At this time, several tens to several hundreds of droplets are continuously discharged from the nozzle 11. Next, after applying the pulse voltage, the contracted electromechanical conversion film 43 returns to its original position, so that the flexed diaphragm 30 returns to its original position, and the functional ink is transferred from the common liquid chamber (not shown) to the pressure chamber 21. Supplied. By repeating the above-described operation control, the liquid ejection head 208 can continuously eject functional ink droplets. It should be noted that functional ink is supplied from an ink tank (not shown) to the liquid discharge head 208 via the ink supply pipe 210.

  The stage 203 has an adsorbing unit that adsorbs and holds the substrate 202 on the main surface of the stage 203 using vacuum, static electricity, or the like.

The head maintenance unit 209 includes a waste liquid receiving unit that receives an empty discharged droplet, a capping unit that caps the discharge surface of the liquid discharge head 208, and a suction unit.
The liquid discharge head 208 is moved to the head maintenance means 209 side during the rest or standby of the apparatus and is capped by the capping means to protect the discharge surface from drying and reaction with moisture in the air.

1 to 3 show a configuration example of the capping means.
FIG. 1 shows a cap member 60 that seals the nozzle surface 208a on which the nozzle 11 of the liquid discharge head 208 is formed, and an atmosphere that is connected in communication with the inside of the cap member 60 and the humidity is controlled inside the cap member 60. FIG. 1A shows a state immediately before capping, and FIG. 1B shows a capped state. FIG. 1A shows a configuration having a purge means for supplying gas.

The sealed space 60a is formed by pressing the cap member 60 against the nozzle surface 208a of the liquid ejection head. A seal member 61 is provided between the cap member 60 and the nozzle surface 208a to improve the adhesion between the cap member 60 and the nozzle surface 208a.
The purge means includes an atmosphere gas supply means 70 and an atmosphere gas supply pipe 71. Low-humidity atmosphere gas is supplied from the atmosphere gas supply means 70 connected through the atmosphere gas supply pipe 71 connected to the inside of the cap member 60.

The functional ink having reactivity with water reacts with moisture in the atmosphere to cause hydrolysis and polycondensation reaction to gel, and adheres at the opening of the nozzle 11 of the liquid discharge head 208 to cause clogging of the nozzle. This can be prevented by lowering the humidity of the atmosphere inside the cap member 60a sealed with the configuration shown in FIGS. 1 (A) and 1 (B).
Furthermore, in the sealed cap member interior 60a, the solvent volatilized from the opening of the nozzle 11 stays in the sealed space, and the vapor pressure of the solvent gradually increases. It can be surely prevented.

  As a method for capping and supplying low-humidity atmospheric gas, for example, low-humidity atmospheric gas is supplied from the atmospheric gas supply means 70 in the state shown in FIG. 1A, and the atmosphere in the cap member 60 is replaced with low-humidity atmosphere. After that, the cap unit 60 can be pressed against the nozzle surface 208a of the liquid discharge head 208 to perform capping as shown in FIG.

Although it does not specifically limit as low humidity atmospheric gas, For example, dry nitrogen is mentioned.
The humidity of the atmosphere inside the cap member 60a during the rest or standby of the apparatus is preferably 10 g / kg (DA: abbreviation of dry air) or less in terms of weight absolute humidity, and is 5 g / kg (DA) or less. Is more preferable.
For example, when the precursor liquid described later as functional ink is filled in the liquid discharge head 208 and left in an atmosphere with a humidity of 10 g / kg (DA), the time until nozzle clogging occurs is about 1 minute. . On the other hand, when left in an atmosphere with a humidity of 5 g / kg (DA), the nozzles were not clogged even after 10 minutes.

  It is known that film quality such as ferroelectric properties of a thin film formed by applying a precursor liquid is greatly affected by humidity during application (for example, Non-Patent Document 1: T. Schneller, R. Waser, J. Sol-Gel Sci. Technol., 42, 337 (2007).). For this reason, it is preferable that the humidity of the atmosphere at the time of application and the humidity of the atmosphere inside the cap member 60a can be controlled independently, and an embodiment including a capping unit and a purge unit as shown in FIG. 1 is preferable.

  On the other hand, in the case where strict control of humidity is not required, it is also possible to provide a mode in which only the capping means without the purge means is provided, as shown in FIG. .

Another aspect of the capping means is shown in FIG.
FIG. 3 shows a configuration including a liquid holding unit 62 capable of holding a liquid and a liquid level sensor 63 inside the cap member 60.
The liquid held in the liquid holding unit 62 is a liquid composed of at least one component constituting the solvent of the functional ink. Although the solvent of the functional ink will be described later, in this embodiment, for example, 2-methoxyethanol which is a component constituting the solvent in the PZT precursor liquid can be selected.

  In the form shown in FIG. 3, the inside of the cap member 60 is connected to the atmospheric gas / liquid supply pipe 65 and the atmospheric gas / liquid supply means 64, and the purge means and the liquid supply means switch a switching valve (not shown). Thus, the supply of the atmospheric gas and the liquid can be switched.

  First, the liquid level of the liquid holding unit 62 is detected by the liquid level sensor 63 before capping. When the liquid level is low, the liquid is supplied from the atmospheric gas / liquid supply means 64 to the liquid holding unit 62. Next, a low humidity atmosphere is supplied from the atmosphere gas / liquid supply means 64, and the atmosphere in the cap portion 60a is replaced with the low humidity atmosphere. Thereafter, the cap member 60 is pressed against the nozzle surface 208a of the liquid discharge head 208 to perform capping.

  According to the configuration of FIG. 3, since the solvent volatilizes not only from the precursor liquid at the nozzle opening but also from the liquid in the liquid holding unit 62, the vapor pressure of the solvent increases rapidly, which is higher than the configuration illustrated in FIG. 1. Drying of the solvent is suppressed and nozzle clogging can be reliably prevented.

[Functional ink]
The functional ink ejected from the nozzle and applied onto the substrate in the thin film manufacturing apparatus of the present embodiment can be appropriately selected according to the type of thin film to be manufactured. For example, an electromechanical conversion film is used. The functional ink containing the metal alkoxide in the case of manufacturing is mentioned, The said metal alkoxide includes what contains at least any one of Pb, Zr, and Ti.

Hereinafter, an example using a precursor liquid used when forming a film of PZT (lead zirconate titanate) as a functional ink by a sol-gel method will be described. The synthesis of the precursor liquid is performed according to a method described in literature (for example, Non-Patent Document 2: T. Iijima, et al., Int. J. Appl. Ceram. Technol., 3, 442 (2006)). Can be performed.
The flow of the synthesis method is shown in FIG.

As starting materials for the PZT precursor liquid, lead acetate trihydrate Pb (CH ₃ COO) ₂ .3H ₂ O, zirconium tetranormal propoxide Zr (OCH ₂ CH ₂ CH ₃ ) ₄ , titanium tetraisopropoxide Ti [ OCH (CH ₃ ) ₂ ] ₄ can be used.
These starting materials are composed of Pb (Zr _0.53 , Ti _0.47 ) O ₃ , generally lead zirconate titanate, generally indicated as PZT (53/47), with a lead content of 20 mol. It is weighed so that the composition becomes% excess, that is, Pb _1.20 (Zr _0.53 , Ti _0.47 ) O ₃ . This is to prevent the deterioration of crystallinity caused by so-called “lead loss” that occurs during the heat treatment of the applied sol-gel liquid film.

After weighing, first, lead acetate trihydrate is dissolved in ₂ -methoxyethanol CH ₃ OCH ₂ CH ₂ OH as a main solvent (S01). Next, heating and refluxing are performed at the boiling point of the solvent (S02), and hydrate dehydration and alcohol exchange treatment of lead acetate are performed (S03).

  Subsequently, zirconium tetranormal propoxide and titanium tetraisopropoxide are added to the 2-methoxyethanol solution of lead acetate subjected to dehydration and alcohol exchange treatment (S04), heated and refluxed (S05), and alcohol exchange is performed. Reaction and polycondensation reaction are allowed to proceed (S06).

An alkoxide compound is dissolved in a 2-methoxyethanol solution, a small amount of acetic acid CH ₃ COOH is added as a stabilizer to prevent hydrolysis of the metal alkoxide (S07), the solid content concentration is adjusted (S08), and the PZT precursor A body sol-gel solution is obtained (S09). In step S08, the solid content concentration can be, for example, 0.5 mol / L, but is not limited thereto.

Next, an ink forming step for applying the obtained precursor sol-gel solution as a functional ink by a thin film manufacturing apparatus by an inkjet method is performed (S10).
In the preparation of the functional ink in the ink forming process in step S10, in order to adjust the drying speed of the ink, the solvent component (main solvent) that is compatible with the prepared precursor liquid and is used in the precursor liquid before preparation is used. The solvent having a boiling point higher than that of the above (hereinafter referred to as “sub-solvent”) is added and stirred. Any one or more of alcohols, glycols, and ethers can be used as a subsolvent. By adding such a subsolvent, it can be stably applied by an ink jet method. An inking precursor liquid is obtained.

In the present embodiment, 2-methoxyethanol is used as the main solvent, and 1-nonanol (CH ₃ (CH ₂ ) ₈ OH) having a higher boiling point than the main solvent and good compatibility with the sol-gel solution is used as the auxiliary solvent. Can do. A functional ink is obtained by setting the volume ratio of the main solvent and the sub-solvent to 1: 1 and diluting the solid content concentration of the precursor liquid. As solid content concentration, although it can be set as 0.3 mol / L, for example, it is not limited to this.

[Electromechanical conversion film, electromechanical conversion element]
The electromechanical conversion film of this embodiment is manufactured by applying the functional ink made of the material of the electromechanical conversion film on the substrate by the thin film manufacturing apparatus.
The electromechanical conversion element of the present embodiment is an electromechanical conversion element having the electromechanical conversion film, the first electrode being the substrate, the second electrode facing the first electrode, The electromechanical conversion film sandwiched between the first electrode and the second electrode.

5 and 7 are cross-sectional views showing the manufacturing process of the electromechanical conversion film and the electromechanical conversion element.
The manufacturing process of the present embodiment shown in FIGS. 5 and 7 relates to a method of directly patterning by applying the functional ink to a desired region on a substrate by an inkjet method using the thin film manufacturing apparatus.

In the step shown in FIG. 5A, TiO ₂ is deposited to a thickness of 50 nm as the base layer 52 on the upper surface of the substrate 51, and platinum (Pt) and strontium ruthenium oxide (SRO) are formed as the first electrodes 53 and 54. Are sequentially stacked. In the present embodiment, the Pt film thickness of the first electrode 53 is 250 mm and the SRO film thickness of the first electrode 54 is 60 nm, but the film thickness is not limited to this.

  In the step shown in FIG. 5B, the photoresist 55 is patterned by photolithography so that the first electrode 54 matches the pattern formed as an electromechanical conversion film by an ink jet method, and electromechanical conversion is performed by dry etching. The SRO layer existing on the surface outside the element pattern region is etched. Subsequently, in the step shown in FIG. 5C, the photoresist 55 remaining on the electromechanical conversion element pattern is peeled off.

The electromechanical conversion film pattern of the present embodiment is a long pattern having a width of 45 μm and a length of 1000 μm, and is arranged at a 1: 1 pitch (pattern width = space width = 45 μm) in the width direction. it can.
The surface outside the electromechanical conversion element pattern region after the patterning step in FIG. 5B is in a state where Pt of the first electrode lower layer 53 exists.

In the step shown in FIG. 5D, surface treatment is performed on the entire surface of the substrate 51 to form a SAM film (Self Assembled Mono-Layer) 58 outside the electromechanical conversion element pattern region. The SAM film 56 is obtained by immersing the substrate in an alkanethiol dilution and allowing the thiol groups to self-align. Here, as the alkanethiol, dodecanethiol CH ₃ (CH ₂ ) ₁₁ —SH is used, and an ethanol dilution solution having a molar concentration of 0.1 mmol / L is used. The immersion time of the substrate 51 in the alkanethiol solution is 10 seconds, and after the immersion, ultrasonic cleaning is performed in an ethanol bath for 5 minutes.

  As a result, the contact angle with respect to pure water inside / outside the electromechanical conversion element pattern area of the substrate is 100 degrees or more outside the pattern area, and sufficient hydrophobicity is obtained, and it becomes 40 degrees or less within the pattern area and becomes hydrophilic. . A large contact angle contrast inside / outside the pattern area can be secured by the above-described steps.

5E, the functional region (precursor liquid) 207 is formed into a hydrophilic region 59 on the substrate, that is, a desired electromechanical conversion film pattern is formed by a thin film manufacturing apparatus equipped with a liquid discharge head 208. Apply to area.
The thin film manufacturing apparatus used for coating includes a maintenance unit 209 as shown in FIG. 6, and the maintenance unit 209 includes a capping unit and a purge unit shown in FIG.
Since the functional ink (precursor liquid) 207 has a contact angle contrast inside / outside the formation region of the electromechanical conversion film pattern as described above, the sol-gel liquid 57a spreads only to the hydrophilic portion, as shown in FIG. Thus, a pattern is formed.

  In the first heating step, that is, the step of drying the solvent, the substrate bottom surface is heated by a hot plate, and the temperature is raised from room temperature to 120 ° C. at a rate of temperature rise of 30 ° C./min. Heat treatment is performed until 57a is dried.

  After the sol film is dried in this step, the second heating step, that is, the thermal decomposition treatment of the organic substance is performed at a temperature of 500 ° C., and the PZT film 57b having the electromechanical conversion film pattern as shown in FIG. Form. The film thickness of the formed electromechanical conversion film is 80 nm at the center of the pattern.

Subsequently, in the step shown in FIG. 7 (H), after performing isopropyl alcohol cleaning as a repetitive treatment, surface treatment of the substrate is performed by dipping in a thiol diluent as in the step of FIG. 5 (D). 56 is formed.
Since the SAM film 56 is not formed on the oxide film, that is, the PZT film 57b after the second time, the pattern of the SAM film 56 as shown in FIG. 7H can be easily obtained.
The contact angle with respect to pure water at this time is 100 degrees or more outside the electromechanical conversion film pattern region (on the SAM film 56) and 25 degrees or less on the PZT film 57b.

Next, as shown in FIGS. 7I and 7J, alignment is performed on the electromechanical conversion film pattern formed first, and the functional ink 207 is again formed by the liquid discharge head 208 using the thin film manufacturing apparatus. Apply.
After the coating, as in the first coating, after a drying step by a temperature increase from room temperature to 120 ° C. at a temperature rising rate of 30 ° C./min, an organic matter thermal decomposition treatment step at a temperature of 500 ° C., and then a crystallization treatment (Temperature 750 ° C.) is performed by RTA (rapid heat treatment), and the overcoated PZT film 57b is obtained. According to such a process, defects such as cracks do not occur in the film.

  Subsequently, a series of steps from formation of the SAM film 56 by surface treatment, application of the functional ink 207, drying, thermal decomposition, formation of the SAM film 56, application of the functional ink 207, drying, thermal decomposition, and crystallization treatment. Can be produced by performing 3 to 30 cycles under the same conditions as described above. As the number of cycles, for example, 21 cycles can be used.

An upper electrode (platinum) was formed on the electromechanical conversion pattern film obtained by the above method, and the electrical characteristics and electromechanical conversion ability (piezoelectric constant) were evaluated.
As a result, the relative permittivity of the electromechanical conversion film was 1400, the dielectric loss was 0.05, and the withstand voltage was 50 V, indicating that it has excellent electrical characteristics.
Further, the remanent polarization was 12.2 μC / cm ² , the coercive electric field was 28.1 kV / cm, and the characteristics were equivalent to those of a normal ceramic sintered body.
Furthermore, the electromechanical conversion capacity was calculated by measuring the amount of deformation by applying an electric field with a laser Doppler vibrometer and fitting it by simulation. As a result, the piezoelectric constant d31 was 142 pm / V, which was the same value as the ceramic sintered body. From the above results, the electromechanical conversion film of this embodiment has characteristics that can be sufficiently designed as an electromechanical conversion element constituting the liquid ejection head.

[Liquid discharge head]
The configuration of a liquid discharge head using the electromechanical transducer of the present invention is shown in FIGS.
The liquid discharge head shown in FIG. 8 is provided with an electromechanical conversion film 43 on the platinum group electrode 42 and the oxide electrode 41 of the lower electrode, and the electromechanical conversion film 43 is formed by applying, for example, platinum ink. The electromechanical conversion element 40 is configured by laminating the upper electrodes 44 thus stacked.
A pressure chamber 21 is configured by the vibration plate 30, the pressure chamber substrate 20 which is a Si substrate, and the nozzle plate 10 provided with the nozzles 11.
In FIG. 8, the liquid supply means, the flow path, and the fluid resistance are omitted.

FIG. 9 is a schematic cross-sectional view showing an example in which a plurality of droplet discharge heads of FIG. 8 are arranged. As described above, the electromechanical conversion element 40 can be easily manufactured without causing clogging at the nozzle opening in discharging the ink on the process surface, and the performance is as high as that of the ceramic sintered body. Can be formed. A liquid discharge head can be obtained by removing etching from the rear surface for forming the pressure chamber 21 and joining a nozzle plate having nozzle holes.
In FIG. 9, liquid supply means, flow paths, and fluid resistance are omitted.

[Inkjet recording device]
An example of an ink jet recording apparatus equipped with the liquid discharge head according to the present invention will be described with reference to FIGS. 10 is a perspective explanatory view of the recording apparatus, and FIG. 11 is a side explanatory view of a mechanism portion of the recording apparatus.

  The ink jet recording apparatus includes a carriage that is movable in the main scanning direction inside the recording apparatus main body 81, a recording head that includes the liquid discharge head that implements the present invention mounted on the carriage, an ink cartridge that supplies ink to the recording head, and the like. A sheet feeding cassette (or a sheet feeding tray) 84 on which a large number of sheets 83 can be stacked from the front side is detachably attached to the lower part of the apparatus main body 81. The manual feed tray 85 for manually feeding the paper 83 can be opened, the paper 83 fed from the paper feed cassette 84 or the manual feed tray 85 is taken in, and the printing mechanism 82 After recording a required image, the image is discharged to a paper discharge tray 86 mounted on the rear side.

  The printing mechanism 82 holds a carriage 93 slidably in the main scanning direction by a main guide rod 91 and a sub guide rod 92 which are guide members horizontally mounted on left and right side plates (not shown). The head 94 formed of the liquid discharge head according to the present invention that discharges ink droplets of each color (Y), cyan (C), magenta (M), and black (Bk) passes through a plurality of ink discharge ports (nozzles) in the main scanning direction. And are mounted with the ink droplet ejection direction facing downward. In addition, each ink cartridge 95 for supplying ink of each color to the head 94 is replaceably mounted on the carriage 93.

  The ink cartridge 95 has an air port that communicates with the atmosphere above, a supply port that supplies ink to the liquid ejection head below, and a porous body filled with ink inside, and a capillary tube for the porous body. The ink supplied to the liquid discharge head by the force is maintained at a slight negative pressure. Further, although the heads 94 of the respective colors are used here as the recording heads, a single head having nozzles for ejecting ink droplets of the respective colors may be used.

  Here, the carriage 93 is slidably fitted to the main guide rod 91 on the rear side (downstream side in the paper conveyance direction), and is slidably mounted on the sub guide rod 92 on the front side (upstream side in the paper conveyance direction). doing. In order to move and scan the carriage 93 in the main scanning direction, a timing belt 100 is stretched between a driving pulley 98 and a driven pulley 99 that are rotationally driven by a main scanning motor 97, and the timing belt 100 is moved to the carriage 93. The carriage 93 is driven to reciprocate by forward and reverse rotation of the main scanning motor 97.

  On the other hand, in order to convey the paper 83 set in the paper feed cassette 84 to the lower side of the head 94, the paper feed roller 101 and the friction pad 102 for separating and feeding the paper 83 from the paper feed cassette 84 and the paper 83 are guided. A guide member 103, a transport roller 104 that reverses and transports the fed paper 83, a transport roller 105 that is pressed against the peripheral surface of the transport roller 104, and a leading end that defines a feed angle of the paper 83 from the transport roller 104 A roller 106 is provided. The transport roller 104 is rotationally driven by a sub-scanning motor 107 through a gear train.

  A printing receiving member 109 is provided as a paper guide member that guides the paper 83 sent from the transport roller 104 below the recording head 94 in accordance with the movement range of the carriage 93 in the main scanning direction. A conveyance roller 111 and a spur 112 that are rotationally driven to send the paper 83 in the paper discharge direction are provided on the downstream side of the printing receiving member 109 in the paper conveyance direction, and the paper 83 is further delivered to the paper discharge tray 86. A roller 113 and a spur 114, and guide members 115 and 116 that form a paper discharge path are disposed.

  At the time of recording, the recording head 94 is driven according to the image signal while moving the carriage 93, thereby ejecting ink onto the stopped sheet 83 to record one line. Record the line. Upon receiving a recording end signal or a signal that the trailing edge of the paper 83 has reached the recording area, the recording operation is terminated and the paper 83 is discharged.

  Further, a recovery device 117 for recovering defective ejection of the head 94 is disposed at a position outside the recording area on the right end side in the movement direction of the carriage 93. The recovery device 117 includes a cap unit, a suction unit, and a cleaning unit. The carriage 93 is moved to the recovery device 117 side during printing standby and the head 94 is capped by the capping means, and the ejection port portion is kept in a wet state to prevent ejection failure due to ink drying. Further, by ejecting ink that is not related to recording during recording or the like, the ink viscosity of all the ejection ports is made constant and stable ejection performance is maintained.

  When a discharge failure occurs, the discharge port (nozzle) of the head 94 is sealed with a capping unit, and bubbles and the like are sucked out from the discharge port with the suction unit through the tube. Is removed by the cleaning means to recover the ejection failure. Further, the sucked ink is discharged to a waste ink reservoir (not shown) installed at the lower part of the main body and absorbed and held by an ink absorber inside the waste ink reservoir.

  As an example of the embodiment, a liquid discharge head and an ink jet recording apparatus including the liquid discharge head have been described. However, the electromechanical conversion film and the electromechanical conversion element of the present invention can also be applied as an optical device or a microdevice. it can. Other application examples will be described below.

[Deflection mirror]
An example of a deflection mirror (MEMS mirror) using the electromechanical transducer of the present invention is shown in FIG.
FIG. 12 is a perspective view showing an entire example of a deflection mirror.
As shown in FIG. 12, the deflection mirror 301 includes a fixed base 302, a mirror unit 303 having a reflecting surface, a support member 304 that supports the mirror unit 303 in a swingable manner, and a support member 304 with respect to the fixed base 302. A beam-like member 305 that supports a part of the beam-like member from both sides thereof, and the electromechanical conversion element 40 of the present invention as external force generating means fixed to the beam-like member 305.

  The beam-shaped member 305 and the electromechanical transducer 40 form a piezoelectric unimorph or bimorph structure, and simultaneously drive the drive beams 306 on both sides in the same direction with the support member 304 interposed therebetween, so that the mirror portion 303 is perpendicular to or rotated in the direction of rotation. Is applied to the support member 304 to vibrate the mirror portion 303.

〔Acceleration sensor〕
An example of an acceleration sensor using the electromechanical transducer of the present invention is shown in FIG.
FIG. 13 is a schematic cross-sectional view illustrating an example of a configuration of a main part of the acceleration sensor.
As shown in FIG. 13, the acceleration sensor 311 has a fixed portion 312c sandwiched between a plurality of substrates 313 and 314 at one end, and a mass portion 312b that is displaced according to acceleration at the other end. The movable substrate 312 having a thin portion 312a formed so as to have a concave cross section between the fixed portion 312c and the mass portion 312b, and the mass portion due to acceleration are disposed on the thin portion 312a of the movable substrate 312. It has the electromechanical transducer 40 of the present invention as a displacement detector for detecting the displacement of 312b.

The movable substrate 312 is made of a silicon material, and a fixed portion 312c in which a thin portion 312b is formed by anisotropic etching is sandwiched between two glass substrates 313 and 314. The electromechanical conversion element 40 provided on the upper portion of the thin portion 312b is composed of a PZT thin film electromechanical conversion film 43 sandwiched between an upper electrode (first electrode) 44 and a lower electrode (second electrode) 45. .
When acceleration is applied to the acceleration sensor 311, the mass portion 312 b is deformed, and the displacement due to this deformation is electrically converted by the electromechanical conversion film 43 and is extracted as an acceleration signal.

[Head position adjusting means]
An example of a head position adjusting means of a hard disk drive (HDD) using the electromechanical transducer of the present invention is shown in FIG.
FIG. 14 is a perspective view showing an example of a main part configuration of the head position adjusting means.
As shown in FIG. 14, the head position adjusting means 321 includes an access arm 326 that is movable in the radial direction of a disk (not shown), a spring member 323 that supports the head 324, and a center that connects the access arm 326 and the spring member 323. The center member 325 includes the electromechanical conversion elements 40a and 40b of the present invention as a pair of swinging means that expand and contract in opposite directions.

  The central member 325 is a flexible member in the head positioning direction, and notches 322a and 322b are formed on both sides. A pair of electromechanical conversion elements (piezoelectric elements) 40a and 40b are expanded and contracted in opposite directions, and the center member 325 is slightly swung left and right to correct off-track of the head 324 mounted with a magnetic or optical module. Follow-up control to the target track can be performed.

[Piezoelectric generator]
Examples of a piezoelectric power generation element using the electromechanical conversion film of the present invention are shown in FIGS. 15 (A) and 15 (B).
FIG. 15A is a schematic diagram illustrating an example of a single plate structure, and FIG. 15B is a schematic diagram illustrating an example of a structure in which a plurality of single plates are stacked.
The piezoelectric power generation element 331 includes a first electrode, upper and lower counter electrodes 46 made of a second electrode facing the first electrode, and an electromechanical conversion film 43 sandwiched between the counter electrodes 46. The mechanical conversion film 43 is polarized in the direction indicated by the arrow. 15A shows the peripheral support 337, and FIG. 15B shows the cantilever 338.

  This is a power generation mechanism in which an external force 336 in substantially the same direction is applied to the illustrated polarization direction 335, and the electromechanical conversion film 43 receives stress from the external force to generate a voltage proportional to the piezoelectric constant. An external force is not applied from the direction orthogonal to the polarization axis.

[Ferroelectric memory]
An example of a ferroelectric memory (FRAM (registered trademark)) using the electromechanical conversion film of the present invention is shown in FIG.
FIG. 16 is a schematic cross-sectional view showing an example of a ferroelectric memory.
The ferroelectric memory 341 includes a substrate 342, a first electrode (Pt) 47 formed on the substrate 342 with an interlayer insulating film 343 interposed therebetween, and a second electrode (Pt) facing the first electrode 47. 48, an electromechanical conversion film 43 of the present invention which is a piezoelectric body (PZT thin film) sandwiched between the first electrode 47 and the second electrode 48, and an interlayer insulating film 343 formed on the second electrode 44 And a third electrode (Al) 345 formed in a contact hole provided in the interlayer insulating film 343 and a protective film (not shown) formed on the third electrode.

  A bit line 346 and a word line 347 are formed on the substrate 342, and a field oxide film 348 is formed on the substrate 342.

(Angular velocity sensor)
An example of an angular velocity sensor using the electromechanical transducer of the present invention is shown in FIG.
FIG. 17 is a perspective view of a vibration gyro-type angular velocity sensor.
The angle sensor 351 includes a pair of prismatic tuning fork type vibrators 353a and 353b, a drive piezoelectric element 40a that is arranged on the vibrator 353, drives the vibrator 353 at a constant period, and a drive piezoelectric element. The piezoelectric element 40b for detection which is arrange | positioned on the vibrator | oscillator 353 so as to be orthogonal to 40a, and detects the displacement of the vibrator | oscillator 353 is provided. The driving piezoelectric element 40a and the detecting piezoelectric element 40b are electromechanical conversion elements of the present invention.

The angular velocity sensor 3451 is, for example, an angular velocity sensor that detects the angular velocity from the Coriolis force generated in the vibration system when the angular velocity is applied to the vibration system that vibrates in a constant direction at a constant cycle, and includes pads 352a and 352b. The angular velocity is detected by detecting the frequency difference between the electromechanical conversion films (PZT thin films) 43 of the driving piezoelectric element 40a and the detecting piezoelectric element 40b.
The vibrator 353 is preferably formed of a material with little thermal expansion.

[Micro pump]
An example of a micropump using the electromechanical transducer of the present invention is shown in FIG.
FIG. 18 is a schematic cross-sectional view showing the configuration of the micropump.
The micro pump 361 includes a vibration plate 362, a piezoelectric element 40 that is an electromechanical conversion element of the present invention that displaces and deforms the vibration plate 362 by piezoelectric displacement, and a flow path 363 through which a fluid flows, and the deformation of the vibration plate 362. The liquid is transported through the flow path 363 by the force generated by the above.
Although not shown in the drawing, an electromechanical conversion film (PZT thin film) 43 has a laminated structure sandwiched between the first electrode and the second electrode.

  As shown in FIG. 18, a plurality of diaphragms 362 are continuously provided in the longitudinal direction. By sequentially driving the diaphragm 362 from the right side in the figure, the fluid in the flow path 200 flows in the direction of the arrow, Transport is possible. FIG. 18 shows an example in which a plurality of diaphragms 362 are provided. However, only one diaphragm may be used, and the shape of the liquid inflow holes and outflow holes can be devised to increase the transport efficiency.

[Micro valve]
An example of a micro valve using the electromechanical transducer of the present invention is shown in FIG.
FIG. 19 is a schematic cross-sectional view showing the configuration of the microvalve.
The microvalve 371 includes an introduction portion 377 for supplying fluid, a discharge portion 376 for discharging fluid, the piezoelectric element 40 that is an electromechanical transducer of the present invention, and a diaphragm (diaphragm) that is driven by the piezoelectric element 40 to vibrate. 373 and control means for controlling the flow of the fluid by opening and closing the liquid flow path according to the vibration of the diaphragm 373.

A disc-shaped substrate 375 having a discharge portion 376 at the center and a vibration plate 373 having a projection 372 serving as a valve and having substantially the same dimensions as the substrate 375 are attached by a fixing portion 374.
The opening / closing means is means for moving the protrusion 372 up and down by applying a voltage to the piezoelectric element 40 to open and close the discharge port of the discharge portion 376. With this mechanism, the microvalve 371 of this embodiment controls the flow of the fluid that has flowed from the introduction portion 377.

10 Nozzle plate 11 Nozzle (nozzle opening)
20 pressure chamber substrate 30 diaphragm 40 electromechanical transducer 41 oxide electrode 42 platinum group electrode (first electrode)
43 Electromechanical conversion film 44 Upper electrode (second electrode)
51 Substrate 52 Underlayer (TiO ₂ )
53 First electrode (Pt)
54 First electrode (SRO)
55 Photoresist 56 SAM film 57a Sol film 57b PZT film 58 Hydrophobic part 59 Hydrophilic part (SRO)
60 Cap member 61 Inside cap member 62 Liquid holding part 63 Liquid level sensor 64 Atmospheric gas / liquid supply means 65 Atmospheric gas / liquid supply pipe 70 Atmospheric gas supply means 71 Atmospheric gas supply pipe 200 Mounting base 201 Y-axis driving means 202 Substrate 203 Stage 204 X-axis indicating member 205 X-axis drive means 206 Head base 207 Functional ink 208 Liquid discharge head 208a Nozzle surface 209 Head maintenance means 210 Ink supply pipe 211 Z-axis drive means 301 Deflection mirror 311 Acceleration sensor 321 Head position adjustment means 331 Piezoelectric generator 341 Ferroelectric memory 351 Angular velocity sensor 361 Micro pump 371 Micro valve

JP 2001-71514 A Japanese Patent No. 4352915 JP 2011-9726 A

T. Schneller, R. Waser, J. Sol-Gel Sci. Technol., 42, 337 (2007). T. Iijima, et al., Int. J. Appl. Ceram. Technol., 3, 442 (2006).

Claims (18)

A stage for holding a substrate;
A liquid ejection head disposed opposite to the stage and ejecting functional ink having reactivity with water from the nozzles by an inkjet method and applying the functional ink onto the substrate;
A cap member for capping the discharge surface of the liquid discharge head,
A thin film manufacturing apparatus, wherein the humidity of the atmosphere inside the cap member sealed by capping is adjusted.   The thin film manufacturing apparatus according to claim 1, further comprising a purge unit that is connected to the inside of the cap member and supplies atmospheric gas with controlled humidity to the inside of the cap member.   The thin film manufacturing apparatus according to claim 1, wherein the functional ink contains a metal alkoxide.   The thin film manufacturing apparatus according to claim 3, wherein the metal alkoxide contains at least one of Pb, Zr, and Ti.   The thin film manufacturing apparatus according to any one of claims 1 to 4, wherein the humidity of the atmosphere inside the cap member is 10 g / kg (DA) or less when the apparatus is at rest or on standby. A liquid holding part capable of holding a liquid inside the cap member;
6. The thin film manufacturing apparatus according to claim 1, wherein the liquid held in the liquid holding unit is a liquid composed of at least one component constituting a solvent of the functional ink.   An electromechanical conversion film produced by applying the functional ink made of a material of an electromechanical conversion film on a substrate by the thin film manufacturing apparatus according to claim 1. An electromechanical transducer having the electromechanical transducer film according to claim 7,
A first electrode serving as the substrate; a second electrode opposed to the first electrode; and the electromechanical conversion film sandwiched between the first electrode and the second electrode. An electromechanical conversion element.   A liquid discharge head comprising the electromechanical conversion element according to claim 8.   An ink jet recording apparatus comprising the liquid discharge head according to claim 9.   A fixed base, a mirror part having a reflective surface, a support member that supports the mirror part so as to be swingable, a beam-like member that supports a part of the support member from both sides of the fixed base, and An external force generating means fixed to a beam-shaped member, wherein the external force generating means drives the beam-shaped member and applies vibration to the support member, thereby deflecting the mirror portion, and the external force A deflecting mirror, wherein the generating means is the electromechanical transducer according to claim 8.   A fixed portion sandwiched between a plurality of substrates is provided at one end portion, a mass portion that is displaced according to acceleration is provided at the other end portion, and a cross section is concave between the fixed portion and the mass portion. In the acceleration sensor, comprising: a movable substrate having a thin portion formed so as to be; and a displacement detection means that is disposed above the thin portion of the movable substrate and detects a displacement of the mass portion due to acceleration. An acceleration sensor, characterized in that the means is the electromechanical transducer according to claim 8. In a head position adjusting means for a hard disk drive, comprising: an access arm movable in a radial direction of the disk; a spring member supporting the head; and a central member connecting the access arm and the spring member.
9. The head position adjusting means according to claim 8, wherein the central member has a pair of oscillating means extending and contracting in opposite directions, and the oscillating means is the electromechanical transducer according to claim 8. A piezoelectric power generation element having the electromechanical conversion film according to claim 7,
A first electrode; a second electrode facing the first electrode; and the electromechanical conversion film sandwiched between the first electrode and the second electrode. A piezoelectric power generation element characterized by being polarized.   A substrate, a first electrode formed on the substrate, a second electrode facing the first electrode, a piezoelectric body sandwiched between the first electrode and the second electrode, and An interlayer insulating film formed on the second electrode, a third electrode formed in a contact hole provided in the interlayer insulating film, and a protective film formed on the third electrode, A ferroelectric memory, wherein the piezoelectric body is the electromechanical conversion film according to claim 7.   A vibrator, a driving piezoelectric element disposed on the vibrator and driving the vibrator in a constant direction at a constant period, and disposed on the vibrator so as to be orthogonal to the driving piezoelectric element, 9. An angular velocity sensor comprising a detecting piezoelectric element for detecting displacement of a vibrator, wherein the driving piezoelectric element and the detecting piezoelectric element are the electromechanical transducer according to claim 8. .   In a micropump that includes a diaphragm, a piezoelectric element that displaces and deforms the diaphragm by piezoelectric displacement, and a flow path through which a fluid flows, and the liquid is transported through the flow path by a force generated by the deformation of the diaphragm. A micropump characterized in that the piezoelectric element is the electromechanical transducer according to claim 8.   An introduction portion for supplying fluid, a discharge portion for discharging fluid, a piezoelectric element, a vibration plate that is driven by the piezoelectric element to vibrate, and opens and closes a liquid flow path according to the vibration of the vibration plate. A microvalve comprising an opening / closing means for controlling the flow of the piezoelectric element, wherein the piezoelectric element is the electromechanical transducer according to claim 8.