JP2015010883A - Method for inspecting surface energy of wettability pattern - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for inspecting surface energy of a wettability pattern, which is capable of improving accuracy of inkjet coating in a method of forming a functional film pattern by inkjet coating.SOLUTION: A method for inspecting surface energy of a wettability pattern includes the steps of: forming, on a substrate, a wettability pattern comprising a high surface energy area A and a low surface energy area B; ejecting liquid drops to at least one or more positions including a position being across the boundary between the areas A and B, by an inkjet device; observing states of the liquid drops landing on the at least one or more positions including the position being across the boundary between the areas A and B, by image inspection means and obtaining a measurement tolerance by measuring an allowable landing shift for complete movement from the area B to the area A, of the liquid drops landing on the at least one or more positions including the position being across the boundary between the areas A and B; and determining whether the measurement tolerance is equal to or higher than a set tolerance preliminarily set or not.

Description

  The present invention includes a surface modification step for forming a wettability pattern on a non-permeable substrate, and an inkjet coating step for forming a pattern following the wettability pattern by discharging droplets onto the wettability pattern. The present invention relates to a surface energy inspection method for wettability patterns introduced during a manufacturing process.

Attention is focused on the method of forming a fine functional film pattern on a wettability pattern using a pattern with different wettability consisting of a lyophilic region (high surface energy region) and a liquid repellent region (low surface energy region). And research is ongoing.
For example, a technique is known in which a color filter is obtained by forming a pixel portion by ejecting ink to a lyophilic region having a pattern with different wettability by an ink jet method. However, since it is difficult to inspect a colorless and transparent pattern having different wettability, in Patent Document 1, the test liquid is adhered to a pattern having different wettability composed of a lyophilic region and a liquid repellent region by a liquid film. There has been proposed a method of examining the test liquid that has been discharged with an inspection means. Specifically, for the purpose of detecting defects in patterns with different surface energies, a test solution (for example, water) was attached to a region with low surface energy, that is, a new liquid region by dip coating or spin coating. A method for inspecting and inspecting an inspection liquid with a CCD element is described.
On the other hand, as one method of forming a ferroelectric film used as a piezoelectric actuator, a ferroelectric precursor film is formed by a CSD method (also called a chemical solution deposition method or a sol-gel method). Then, a method of forming a film by repeating crystallization by heating and baking treatment a predetermined number of times is known. In addition, a ferroelectric precursor sol is applied using an ink jet coating mechanism, the sol (ink) is subjected to a heat treatment to crystallize the sol, and a ferroelectric thin film is formed to form a pattern. There has also been proposed a method of forming the ferroelectric film. By setting the surface of the substrate to be coated in a state where the surface energy is patterned in advance, the ink spreads only in a desired region, and even if the ink landing position is shifted, correction can be performed and coating accuracy can be improved. For example, Patent Document 2 proposes a method of forming a functional film having a predetermined pattern by selectively supplying a functional liquid to a predetermined dropping position in a high surface energy region using an ink jet method.
According to the methods proposed in Patent Document 1 and Patent Document 2, regions having different surface energies composed of a low surface energy region and a high surface energy region are formed on a non-printing surface, and selectively formed in the high surface energy region. Since the functional liquid is supplied, the functional film pattern can be miniaturized. However, in order to form a functional film pattern without short-circuiting to a high surface energy region or to precisely control the film thickness of the functional film pattern, the functional liquid is accurately supplied to the printing surface. There was a need to do.

As described in the above-mentioned prior art, the substrate to be coated is previously formed as a pattern having different wettability composed of a lyophilic region (high surface energy region) and a liquid repellent region (low surface energy region). Accuracy can be increased. In surface energy patterning, it is desirable that the surface energy difference (surface energy contrast) between the high surface energy region and the low surface energy region is large. Since the surface energy is affected by the state of the outermost surface of the substrate, the surface energy of the substrate may change due to adhesion of organic substances or resist residues. If the functional liquid is applied while the surface energy contrast is small, the landing position deviation cannot be corrected and the application accuracy is deteriorated. In order to prevent this, it is necessary to inspect the surface energy of the wettability pattern of the substrate in advance before the inkjet application.
However, the conventional method for inspecting the surface energy contrast of a substrate has a problem in that it is necessary to measure the contact angles of a high energy surface and a low energy surface, and the operation is complicated. In addition, when the functional liquid is selectively supplied as droplets on the wettability pattern (high energy surface) using the ink jet method to form a functional film of a predetermined pattern, the landing position of the droplets in the conventional inspection method It is difficult to determine the allowable amount of deviation, to increase the accuracy of the inkjet, and to set and maintain stable conditions.
The present invention has been made in view of the above-described prior art, and includes a surface modification step for forming a wettability pattern on a non-permeable substrate and a wettability pattern by discharging droplets onto the wettability pattern. A liquid used in forming a pattern that follows the wettability pattern in the inkjet coating process by simply inspecting the surface energy of the wettability pattern. It is an object of the present invention to provide a method for inspecting the surface energy of a wettability pattern that can obtain an allowable amount of droplet landing position deviation and can improve the accuracy of inkjet coating.

As a result of intensive studies, the present inventors have ejected droplets by an ink jet apparatus at a position including a portion straddling the regions A and B of the wettability pattern composed of the high surface energy region A and the low surface energy region B. The present inventors have found that the above problems can be solved by a simple inspection method for observing the behavior due to the surface energy contrast of the landed droplets with an image inspection means.
That is, the present invention includes a surface modification step for forming a wettability pattern on a non-permeable substrate, and an ink jet coating step for forming a pattern following the wettability pattern by discharging droplets on the wettability pattern. A surface energy inspection method for a wettability pattern introduced during a manufacturing process comprising:
Forming a wettability pattern composed of a high surface energy region A and a low surface energy region B on a non-permeable substrate by a surface modification step;
A step of ejecting droplets by an ink jet device at at least one position including a portion straddling the boundary line between the high surface energy region A and the low surface energy region B;
A process of observing the form of a droplet landed on at least one position including a portion straddling a boundary line between the high surface energy region A and the low surface energy region B by an image inspection means to obtain the following measurement allowable value;
And a process for determining whether or not the measurement allowable value is greater than or equal to a preset allowable value.
[Measurement tolerance]: A droplet landed on at least one position including a portion straddling the boundary line between the region A and the region B by the surface energy contrast between the region A and the region B is completely moved from the region B to the region A. An allowable value set based on the shortest distance from the center of the droplet at the allowable landing position to the boundary line between the area A and the area B.

  The surface energy inspection method of the wettability pattern of the present invention can easily inspect the surface energy of the wettability pattern and can improve the accuracy of the ink jet coating process based on the obtained landing position deviation tolerance.

FIG. 6 is a schematic diagram illustrating a target landing position of a droplet discharged by an ink jet apparatus at a position including a portion straddling a boundary line between a high surface energy region A and a low surface energy region B. It is a schematic diagram showing the actual landing position of a droplet moved by the surface energy contrast of the high surface energy region A and the low surface energy region B. It is a figure which shows the example of an inspection flowchart at the time of introducing the surface energy inspection method of the wettability pattern of this invention into the manufacturing process which produces an electromechanical conversion element. It is a schematic diagram which shows a mode that a droplet is discharged with an inkjet apparatus on the wettability pattern divided into the area | region A and the area | region B by the process including (Ia)-(Id), and a PZT coating film is formed repeatedly. It is a schematic diagram which shows a mode that a droplet is discharged with an inkjet apparatus on the wettability pattern divided into the area | region A and the area | region B by the process including (IIa)-(IIc), and a PZT coating film is formed. It is a top view which shows typically the non-permeable board | substrate which provided the wettability pattern for a test | inspection with the wettability pattern actually used. It is a perspective view which shows the structural example of an inkjet apparatus. It is a schematic sectional drawing which shows the structural example of the droplet discharge head provided with the electromechanical conversion element. FIG. 9 is another schematic cross-sectional view illustrating a configuration example of a droplet discharge head configured by arranging a plurality of electro-mechanical conversion elements illustrated in FIG. 8. 1 is a perspective view illustrating an example of an ink jet recording apparatus including a droplet discharge head according to the present invention. It is side surface explanatory drawing of the mechanism part of the inkjet recording device shown in FIG.

As described above, the surface energy inspection method of the wettability pattern according to the present invention includes a surface modification step of forming a wettability pattern on a non-permeable substrate, and wettability by discharging droplets onto the wettability pattern. A method of inspecting the surface energy of a wettability pattern introduced during a manufacturing process comprising: an inkjet coating process for forming a pattern following the pattern;
Forming a wettability pattern composed of a high surface energy region A and a low surface energy region B on a non-permeable substrate by a surface modification step;
A step of ejecting droplets by an ink jet device at at least one position including a portion straddling the boundary line between the high surface energy region A and the low surface energy region B;
A process of observing the form of a droplet landed on at least one position including a portion straddling a boundary line between the high surface energy region A and the low surface energy region B by an image inspection means to obtain the following measurement allowable value;
And determining whether or not the measurement allowable value is equal to or greater than a preset allowable value.
[Measurement tolerance]: A droplet landed on at least one position including a portion straddling the boundary line between the region A and the region B by the surface energy contrast between the region A and the region B is completely moved from the region B to the region A. An allowable value set based on the shortest distance from the center of the droplet at the allowable landing position to the boundary line between the area A and the area B.

  According to the inspection method of the present invention, the surface energy is a high surface energy region A (hereinafter sometimes referred to as “region A”) and a low surface energy region B (hereinafter sometimes referred to as “region B”). In the surface energy inspection of the so-called wettability pattern patterned on the surface, a droplet is ejected by an inkjet device to at least one or more positions including a portion straddling the boundary line between the region A and the region B. The target landing position is compared with the actual droplet position (the droplet that has landed across the region B moves to the region A due to the surface energy contrast between the region A and the region B) to obtain a measurement allowable value. Thus, it is characterized in determining whether or not it is greater than a preset allowable value.

A wettability pattern surface energy inspection method (hereinafter sometimes abbreviated as “wetability pattern inspection method”) will be described in detail with reference to the drawings.
FIG. 1 is a schematic diagram showing a target landing position of a droplet ejected by an ink jet apparatus at a position including a portion straddling a boundary line between a high surface energy region A and a low surface energy region B.
FIG. 2 is a schematic diagram showing the actual landing position of a droplet moved by the surface energy contrast (high, low) of the high surface energy region A and the low surface energy region B.

As shown in FIG. 1, a non-permeable substrate (hereinafter abbreviated as “substrate”) on which a wettability pattern in which a high surface energy region A and a low surface energy region B are separated by a boundary line (straight line) (L1) is formed. Be prepared). Liquid droplets are ejected from the ink jet apparatus onto this substrate, ejected in a straight line intersecting the boundary line (L1), and landed as a liquid droplet array (L2). As shown in FIG. 1, the boundary line between the high surface energy region A and the low surface energy region B is preferably linear.
The circles in FIG. 1A indicate the target landing positions of the droplets. For example, the droplets straddling the boundary line between the high surface energy region A and the low surface energy region B like the droplets b to d are total. It shows the behavior of moving from the target landing position that is likely to be drawn into the high surface energy region A so as to lower the surface / interface energy.

In general, if the surface energy contrast between the high surface energy region A and the low surface energy region B is sufficient, if even a part of the droplet enters the high surface energy region A, the region B straddles the boundary line between the region A and the region B. The droplets that have landed on the surface move from the target landing position and are drawn into the high surface energy region A. However, when the surface energy contrast is small, the driving force for moving the droplet from the region B to the region A is small, and the movement takes time. In the case of a liquid that dries quickly, some of the droplets start to adhere to the substrate before the movement is completed, and eventually the droplets also remain in the region B. That is, since the ease of being drawn depends on the surface energy contrast, the way the droplets spread varies depending on the surface energy contrast of the substrate as shown in FIGS.
That is, the surface energy of the substrate can be inspected by measuring how the droplets b to d shown in FIG.
In the case of the surface energy contrast between the region A and the region B in FIG. 2B, all the droplets whose target landing positions straddle the region A and the region B move to the region A, and a marginal allowable landing deviation is obtained. The measurement tolerance measured based on this increases. If droplets are ejected from the ink jet apparatus to a wettability pattern having a measurement tolerance greater than a predetermined set tolerance, a fine pattern following the wettability pattern can be formed with high accuracy. That is, if the surface energy states of the region A and the region B in FIG. 2B are sufficient, it can be determined that the surface energy contrast is sufficient and an acceptable wettability pattern can be formed.
On the other hand, in the case of the surface energy contrast between the region A and the region B in FIG. 2 (C), the droplets whose target landing positions straddle the region A and the region B are recognized to move to the region A, but partially. Remaining in the region B, the allowable landing deviation is extremely small and there is no tolerance for the allowable landing deviation. That is, if the surface energy states of the region A and the region B in FIG. 2C are used, it can be determined that the surface energy contrast is insufficient and an unacceptable wettability pattern is formed.

As described above, the measurement allowable value is set based on the measured allowable amount of landing position deviation. That is, landing at at least one position (particularly a position biased toward the area B) including a portion straddling the boundary line between the area A and the area B due to the surface energy contrast between the high surface energy area A and the low surface energy area B. The permissible landing deviation in which the liquid droplet completely moves to the region A is measured, and a measurement allowable value is set based on the shortest distance from the center of the droplet to the boundary line (L1) between the region A and the region B.
For example, when the surface energy contrast of FIG. 2B is high, the shortest distance from the center of the droplet a at the target landing position to the boundary line (L1) of the region A and the region B is la, which is the target. When the landing position is the droplet b, the shortest distance is lb. For this reason, the measurement tolerance is lb. The allowable measurement value in FIG. 2C is la.
The set allowable value is determined in consideration of the specifications of the nozzle bending of the inkjet head and the misalignment of the coating apparatus.

  As described above, the measurement allowable value can be determined from the movement of the plurality of droplets from the actual landing position, and the surface energy inspection of the wettability pattern can be easily performed. At that time, in order to know the movement from the landing position, it is necessary to know the target landing position. For that purpose, the target landing position of the droplets ejected by the ink jet apparatus at at least one position including the portion straddling the boundary line (L1) between the high surface energy region A and the low surface energy region B (see FIG. 1). b to d) shows the position of a droplet (see FIG. 1: a) completely landed in the high surface energy region B (no fear of movement) and the risk of movement completely landed in the high surface energy region A. It can be estimated from the position of the liquid droplet (see FIG. 1: e) that does not exist.

In order to know the target landing position, an ink jet device crosses the boundary line (L1) between the high surface energy region A and the low surface energy region B and discharges it linearly to land as a droplet row (L2). It is preferable to do so. At this time, it is preferable that the droplet arrays (L2) are formed by using an inkjet apparatus having the same nozzles of the inkjet head and arranging the landing intervals of the droplets at equal intervals D.
Thus, if the landing interval of each droplet is D and the crossing angle between the boundary line (L1) and the droplet row (L2) is θ, the boundary from each droplet is expressed as shown in the following formula (1). Droplets having different distances to the line (L1) by D × sin θ are arranged. This can be used to know the target landing position.
Difference in distance from the center of each droplet to the boundary line (L1) = D × sin θ (1)
In order to increase the accuracy of measurement of the measurement tolerance, the landing interval D and / or θ may be controlled to be small.

As a manufacturing process for introducing the surface energy inspection method of the wettability pattern of the present invention, a surface modification step for forming the wettability pattern on the non-permeable substrate, and droplets are ejected onto the wettability pattern. For example, an electro-mechanical conversion film (for example, lead zirconate titanate) using a printing technique based on an inkjet method capable of forming a fine pattern. : PZT)) to form an electromechanical conversion element.
Although the manufacturing process which produces an electromechanical conversion element is not limited, For example, what includes the following processes is illustrated.
(Ia) A step of forming a first electrode made of metal [for example, platinum (Pt)] (Ib) A step of forming a second electrode made of a conductive oxide formed on the first electrode (Ic ) Applying a treatment [for example, SAM film (self-assembled monomolecular film)] to make only the surface of the first electrode a hydrophobic region (low surface energy region B), the second electrode (high surface energy region A) (Id) Inkjet coating process for forming an electro-mechanical conversion film by ejecting droplets by an inkjet device onto the second electrode having a wettability pattern,
(Ie) Step of forming the upper electrode (third electrode) on the electro-mechanical conversion film The first electrode and the second electrode are stacked to form the lower electrode. Examples of the conductive oxide include a general formula ABO ₃ (where A represents an element selected from Sr, Ba, Ca, La, and B represents Ru, Co, Ni, Mn, Al, Cr). And an oxide having a perovskite structure represented by:

  Here, the substrate on which the first electrode and the second electrode are formed corresponds to a non-permeable substrate. That is, the surface of the non-permeable substrate is composed of a noble metal surface and a non-noble metal surface, the low surface energy region B is formed by surface modification of the noble metal surface, and the high surface energy region A is the non-noble metal surface. It is formed by a surface (see FIG. 4 described later).

Further, another example of the manufacturing process for producing the electromechanical conversion element includes one including the following steps.
(IIa) Process of treating the entire surface of a metal [for example, platinum (Pt)] [for example, SAM film (self-assembled monomolecular film)] to form a hydrophobic region (low surface energy region B) (IIb) Low Surface modification in which a part of the surface energy region B is stimulated from the outside [for example, dry etching is performed using a resist pattern] to be partially changed to form a wettability pattern (high surface energy region A) Step (IIc) Inkjet coating step of forming an electro-mechanical conversion film by discharging droplets on the wettability pattern (lower electrode) by an inkjet device,
(IId) Step of forming the upper electrode on the electromechanical conversion film

  That is, the surface of the non-permeable substrate is composed of a noble metal surface, the low surface energy region B is formed by subjecting the noble metal surface to surface modification, and the high surface energy region A is a region of the low surface energy region B. A part is formed by applying a stimulus from the outside to be partially changed (see FIG. 5 described later).

For surface modification of the noble metal surface, it is preferable to form a SAM film using a thiol compound.
A self-assembled monomolecular film (SAM film: Self Assembled Mon-layer film) is formed by applying a solution containing a material for SAM formation on the entire surface of a noble metal. Although the material for forming the SAM varies depending on the material of the base, it is preferable to mainly select a thiol compound (for example, alkanethiol) when using a metal as the base.
When alkanethiol is used, the reactivity and hydrophobicity (water repellency) differ depending on the molecular chain length, but normally molecules having C6 to C18 carbon numbers are dissolved in common organic solvents (alcohol, acetone, toluene, etc.) (concentration) A solution for SAM formation is prepared by several mmol / l). Using this solution, a coating treatment is performed on the substrate by any of dipping, steam, spin coater, etc., and surplus molecules are replaced and washed with a solvent and dried to form a SAM.
In (IIb), a photoresist is patterned on the SAM film by photolithography, and the SAM film where the photoresist is not formed is removed by dry etching to obtain a hydrophilic region (high surface energy region A) and a hydrophobic region. A wettability pattern is formed by dividing into (low surface energy region B).

The electro-mechanical conversion film used in the step of forming the electro-mechanical conversion film of (Id) and (IIc) is not limited, but a PZT film is preferably used. PZT is a solid solution of lead zirconate (PbZrO ₃ ) and titanic acid (PbTiO ₃ ), and the characteristics differ depending on the ratio. In general, the composition exhibiting excellent piezoelectric characteristics is expressed as Pb (Zr _0.53 , Ti _0.47 ) O ₃ in a chemical formula where the ratio of PbZrO ₃ and PbTiO ₃ is 53:47, Generally indicated as PZT (53/47).
The electro-mechanical conversion film (for example, PZT) is formed by an inkjet method (a precursor solution is discharged as droplets by an inkjet apparatus) using a precursor solution (PZT precursor solution) for an electro-mechanical conversion film. Is done. The PZT precursor solution can be prepared by using lead acetate, zirconium alkoxide, and titanium alkoxide compounds as starting materials and dissolving them in methoxyethanol as a common solvent to obtain a uniform solution.
Examples of composite oxides other than PZT include barium titanate. In this case, a barium titanate precursor solution is prepared by using a barium alkoxide compound and a titanium alkoxide compound as starting materials and dissolving them in a common solvent. It is also possible.

The electro-mechanical conversion film is formed on the electrode by an inkjet method. At that time, on the wettability pattern (electrode) previously divided into a high surface energy region A and a low surface energy region B, after forming a coating film by ejecting and landing the precursor solution as droplets by an inkjet device, An electro-mechanical conversion film can be obtained by subjecting the coating film to heat treatment (solvent drying, thermal decomposition, crystallization).
When this electro-mechanical conversion film is formed, the transformation from the coating film to the crystallized film involves volume shrinkage, so that a film having a thickness of 100 nm or less can be obtained in one step in order to obtain a crack-free film. It is necessary to adjust the concentration of the precursor solution. For this reason, in order to form an electromechanical conversion film having a thickness of about several μm, it is necessary to repeatedly form a film having a thickness of 100 nm or less by an ink jet method and to produce a plurality of coating films. A process of repeatedly producing a PZT coating layer by repeatedly ejecting a precursor solution (precursor sol) as droplets by an ink jet apparatus on a wettability pattern (electrode) is shown in FIG. 4 described later.

  The wettability pattern forming method is not particularly limited as long as it is a method capable of patterning the surface energy of the outermost surface of the substrate. A substrate composed of a plurality of layers may be patterned by etching to expose a part of the surface of the lower layer, or a surface treatment may be performed in a pattern on a substrate composed of a single wettability changing material. As the wettability changing material described here, a material whose surface energy is changed by physical or chemical stimulation such as thermal energy or light energy is preferably used.

The wettability pattern surface energy inspection method of the present invention includes a surface modification step of forming a wettability pattern on a non-permeable substrate, and a pattern imitating the wettability pattern by discharging droplets onto the wettability pattern. It is preferably introduced during the inkjet coating process for forming the film.
That is, the manufacturing process for producing the electromechanical conversion element includes a surface modification step for forming a wettability pattern on a non-permeable substrate, and a droplet is ejected onto the wettability pattern to follow the wettability pattern. Since the inkjet coating process for forming the pattern is repeated a plurality of times, the inspection is preferably carried out after each of the plurality of surface modification processes. If it can be determined that the droplet ejection can be reliably reproduced in the range of the allowable landing position deviation in the ink jet coating process, it is possible to omit the inspection after the first to n-th time. For example, if it can be determined by the first inspection that the droplet discharge can be reliably reproduced in the range of the allowable landing position deviation, the second and subsequent inspections can be omitted.

FIG. 3 shows an example of an inspection flowchart in the case where the surface energy inspection method for wettability patterns of the present invention (shown as “wetability inspection” in the figure) is introduced into the manufacturing process for producing the electromechanical conversion element.
As described above, the wettability inspection method includes a surface modification step [a high surface energy region A and a low surface energy region B that forms a wettability pattern on a non-permeable substrate in a manufacturing process for producing an electromechanical conversion element. Between the ink-jet coating process (formation of the PZT film) in which droplets are ejected onto the wettability pattern to form a pattern imitating the wettability pattern. Is done.
Introduced the surface energy inspection method of the wettability pattern of the present invention, and after the surface modification step, the measurement allowable value obtained by observing the form of the droplet ejected and landed by the ink jet device by the image inspection means is set An electro-mechanical conversion film (PZT film) having a desired film thickness is determined by repeating the ink-jet coating process (shown as “coating process” in the figure) and the heating process a predetermined number of times while determining whether or not the value is greater than the allowable value. Form. Here, the predetermined number of times, as described above, requires a film thickness of 100 nm or less in one step in order to obtain a crack-free PZT film, and 20 times in order to make the thickness of the PZT film several μm. It is necessary to repeat the above (for example, about 24 times).

In the schematic diagram of FIG. 4, a precursor solution (precursor sol) is ejected as droplets by an inkjet device onto a wettability pattern (electrode) divided into a high surface energy region A and a low surface energy region B, and PZT coating is performed. A state in which a plurality of layers are repeatedly stacked is shown.
FIG. 4A shows a state on a non-permeable substrate (abbreviated as “substrate”) before the surface modification step. The substrate has a platinum film on a silicon wafer and a conductive oxide film formed on a part of the platinum film.
That is, the first electrode [for example, platinum (Pt)] made of the metal formed by (Ia) exemplified in the manufacturing process for producing the electro-mechanical conversion element, and the conductive oxidation formed by (Ib) This corresponds to a second electrode made of a material.
Platinum and oxide electrodes (for example, SrRuO ₃ ) are formed by sputtering, but are patterned by photolithography and etching processes.

A method for partially forming a SAM film in the surface modification step will be described. For example, a phenomenon is used in which a thiol compound (alkanethiol) does not adhere to the oxide surface and self-aligns with a platinum group metal. The SAM film formed on the platinum group metal has low surface energy because the alkyl group is arranged on the surface side.
Therefore, in this example, a silicon wafer having a lower electrode in which an oxide is partially formed on platinum as shown in FIG. 4A is used as an alkanethiol solution, for example, CH ₃ (CH ₂ ) _n —SH , 6-18 are preferred) are immersed (dip) in a solution in an organic solvent (alcohol, acetone, toluene, etc.).
Alkanethiol has a property of forming a SAM film only on a platinum group metal, and the SAM film is formed only on platinum. As a result, a wettability pattern (having a wettability contrast) divided into a high surface energy region A and a low surface energy region B is formed (FIG. 4B). Thus, the contact angle of water with platinum surface-modified with the SAM film was 100 ° or more.
A droplet made of a PZT precursor solution is ejected onto the wettability pattern by an inkjet coating process to form a pattern that follows the wettability pattern (FIG. 4C), and heat treatment is performed to form a PZT film (FIG. 4D).
Since the SAM film disappears in the heating process, it is necessary to perform SAM treatment before the second and subsequent coatings. In the second and subsequent times, the SAM treatment is performed on the substrate on which the PZT film is formed only on the oxide electrode. However, the SAM film is not formed on the PZT film that is an oxide, but only on the platinum. Since the SAM film is formed, the same wettability contrast as in the first treatment is formed.

  As shown in FIG. 3, after the surface modification step, the surface energy inspection method of the wettability pattern of the present invention is introduced, and the form of the liquid droplet ejected and landed by the ink jet apparatus is observed by the image inspection means. The electro-mechanical conversion film (PZT film) having a desired film thickness is formed by repeating the ink jet coating process while determining whether the allowable measurement value is equal to or greater than the set allowable value.

Further, in FIG. 5, the high surface energy region A and the low surface energy region B were divided by the steps including (IIa) to (IIc) shown in another example of the manufacturing process for producing the electro-mechanical conversion element. The schematic diagram in the case of producing a PZT coating film by discharging a precursor solution (precursor sol) as droplets by an ink jet apparatus on a wettability pattern (electrode) is shown.
In FIG. 5, the surface of the non-permeable substrate is composed of a noble metal surface, the low surface energy region B is formed by subjecting the noble metal surface to surface modification, and the high surface energy region A is the low surface energy region B. A part is formed by applying a stimulus from the outside and changing it partially.
FIG. 5 is the same as the other steps except that the steps of the high surface energy region A and the low surface energy region B in FIG. 4 are different. The substrate is formed of platinum (Pt) to be an electrode (lower electrode) on a silicon wafer.
First, a SAM film is formed by coating the entire surface of the substrate surface with a solution containing a SAM forming material. As a film forming method, for example, the substrate is immersed (dip) in an alkanethiol solution to form a SAM film on the entire surface of Pt (FIG. 5b-1).
Next, a photoresist is patterned on the SAM film by photolithography.
FIG. 5b-2 shows a photolithography process for protecting the SAM film necessary for removing the SAM film in the wettability pattern region and dividing it into the high surface energy region A and the low surface energy region B. A state in which the resist is patterned is shown.
In FIG. 5b-3, the SAM film where the photoresist is not formed is removed by performing dry etching on the substrate surface patterned with the photoresist, for example, by irradiating the substrate surface with oxygen plasma. By such surface modification treatment, a wettability pattern is formed by being divided into a high surface energy region A and a low surface energy region B.
FIG. 5c is an inkjet coating process in which a precursor solution (precursor sol) is ejected as droplets by an inkjet device onto a wettability pattern (electrode) in the same manner as described in FIG. Indicates.
Although FIG. 5 illustrates an example in which the SAM film is removed with oxygen plasma and the surface modification process is performed, the surface modification process may be performed by irradiation with ultraviolet rays (UV light).

In the surface energy inspection method of the wettability pattern of the present invention introduced between the surface modification step and the inkjet coating step, an inspection pattern is provided in advance in addition to the wettability pattern actually used. Can be used.
FIG. 6 is a plan view schematically showing an example of a non-permeable substrate provided with a wettability pattern for inspection in combination with a wettability pattern actually used.
In FIG. 6, the wettability pattern (application pattern) to be actually used is a pattern made of an oxide electrode having a rectangular shape (the dimensions are appropriately determined according to the purpose. In the embodiment, 1000 μm × 50 μm). The wettability pattern (inspection pattern) is an oxide electrode having a rectangular shape (the dimensions are appropriately determined according to the purpose. In the embodiment, 500 μm × 50 μm). The inspection pattern is provided so as to be inclined (in the embodiment, θ = about 5 °) with respect to the coating pattern.
If droplets are ejected by an ink jet device in parallel to the Y axis with respect to the inspection pattern having such an arrangement, the inspection pattern is positioned at a position including a portion straddling the boundary (L1) between the high surface energy region A and the low surface energy region B. , Droplets can be landed.
The form of the landed droplet is observed by the image inspection means, and the measurement allowable value obtained from the observed liquid droplet form (position / spreading, movement, etc.) is compared with the set allowable value. If the measurement allowable value is equal to or greater than the set allowable value, it is determined that the ink-jet application process (for example, formation of a PZT film) can be allowed for the wettability pattern (application pattern) that is actually used, and the manufacturing process can proceed. it can. On the other hand, when the measurement allowable value is less than the set allowable value, it is determined that it is necessary to correct the surface modification process or improve the landing position deviation of the droplet.
The form (position / spreading, movement, etc.) of the droplets shown in FIGS. 1 and 2 is observed by image inspection means, and a microscope such as an optical microscope is used as such image inspection means.
When using SrRuO ₃ as the oxide electrode, the surface energy of the PZT is because of the higher tendency than SrRuO _3, SrRuO ₃ and platinum the second and subsequent Invite Torere sufficient surface energy contrast test can be omitted .

FIG. 7 is a perspective view illustrating a configuration example of the ink jet apparatus.
In the inkjet apparatus of FIG. 7, a Y-axis driving unit 201 is installed on the gantry 200, and a stage 203 on which the substrate 202 is mounted is installed on the platform 200 so as to be driven in the Y-axis direction. The stage 203 is provided with suction means such as vacuum and static electricity (not shown), and the substrate 202 is fixed. An X-axis drive unit 205 is attached to the X-axis support member 204, and a head base mounted on the Z-axis drive unit 211 is attached to the X-axis support member 204 so that it can move in the X-axis direction. Yes. An ink jet head 208 that discharges liquid is mounted on the head base. Liquid is supplied to the droplet discharge head 208 through a supply pipe 210 from a liquid tank (not shown).

The ink jet head 208 mounted on the ink jet apparatus shown in FIG. 7 has two scanning directions of X and Y, and can eject droplets at predetermined positions. For example, droplets can be ejected following the pattern shown in FIG. 6 (the wettability pattern for inspection and the wettability pattern actually used).
As shown in FIG. 6, the coating pattern actually used on the substrate is rectangular, but the stage on which the substrate is placed is rotated so that the scanning pattern and the coating direction are parallel, and the alignment mark on the substrate The position of the substrate is measured by using a microscope attached to a coating apparatus (not shown).
As a result, the inspection pattern is inclined with respect to the scanning direction Y by θ of about 5 °, for example, and the boundary line between the high surface energy region A and the low surface energy region B constituting the inspection pattern. The droplets can be ejected by the ink jet device to a position including the portion extending over the area.
As shown in FIG. 1, droplets are ejected in a straight line with the target landing position intersecting the boundary line (L1) and landed as a droplet row (L2). For example, as in the embodiment, the landing interval of each droplet is set to 40 μm, and the droplet (precursor sol ink) is ejected at 8 pl to be landed.

The form of the landed droplet is observed and inspected by an image inspection means (microscope). The inspection is performed with the substrate 202 placed on the stage 203 using a microscope (optical microscope) attached to the coating apparatus.
It is determined whether or not the measurement allowable value is greater than or equal to a set allowable value. This allowable setting value, that is, the allowable amount of landing position deviation is a variation that is allowed when droplets are ejected aiming at a position across the boundary between the high surface energy region A and the low surface energy region B.
Here, how to determine the measurement allowable value will be described. When droplets are ejected onto the coating pattern, the landing position shifts due to the influence of the substrate positioning (alignment) error and the nozzle bending of the inkjet head. Assuming that droplets are ejected aiming at the center line of the coating pattern with a landing position deviation of ± 35 μm and a width of 50 μm at the time of coating, the center of the droplet after landing is 35− from the end of the coating pattern. There is a possibility of deviation from 50/2 = 10 (μm). Therefore, the set allowable value may be set to 10 μm.

As a result of the inspection, if the surface energy contrast is not sufficient and the measurement allowable value does not match the set allowable value (does not satisfy the set allowable value), it is evaluated that the substrate is not suitable for the inkjet coating process. If it is less than the set allowable value, the precursor sol ink is dried by heating, and then the surface modification treatment is performed again, and the surface energy inspection (wetting test) of the wettability pattern is performed. After it is determined that the wettability test is passed, the next inkjet coating process is performed.
If there is a concern about in-plane variation of the surface energy of the substrate, a plurality of wettability test patterns may be arranged in the substrate.

In the next inkjet coating process, droplets (PZT precursor sol ink) were ejected onto a wettability pattern (liquid droplet ejection row for coating) as shown in FIG. A pattern (PZT film) is formed.
Since the substrate has already been rotated and positioned in the previous wettability inspection process, ink jet application can be performed quickly. For example, as shown in FIG. 4, since there is a wettability pattern, even if a landing position shift occurs due to nozzle variation of an inkjet head mounted on the inkjet apparatus, the wettability pattern causes the liquid droplets on the oxide electrode. Then, the PZT film can be patterned with higher accuracy (FIG. 45C).
In the heating process shown in FIGS. 4D and 4F, the substrate is heated up to 700 ° C. to be dried, pyrolyzed, and crystallized. By repeating these steps, a PZT film having a thickness of 1 μm or more can be formed.

Note that a silicon single crystal (SiO ₂ ) plate is preferably used as the base of the non-permeable substrate used in the manufacturing process of the electro-mechanical conversion element. However, when a noble metal (especially platinum) is used as the electrode, it is preferable to use an adhesion layer because a silicon single crystal (SiO ₂ ) plate is used as a base and adhesion is poor. An example of the adhesion layer is TiO ₂ . The adhesion layer can be formed by sputtering.
In addition, the upper electrode or the third electrode is effectively composed of a conductive oxide in the same manner as the second electrode. Specifically, it is represented by the general formula ACO ₃ (where A represents an element selected from Sr, Ba, Ca, and La, and C represents an element selected from Ru, Co, and Ni). And conductive oxides. Examples thereof include SrRuO ₃ and CaRuO ₃ . It is also effective to use platinum group elements such as platinum, iridium and platinum-rhodium, these alloy films, Ag alloy, Cu, Al, and Au on the conductive oxide in order to supplement the wiring resistance.
As a method for producing the upper electrode or the third electrode, it can be produced by a spin coater using a sputtering method or a sol-gel method. In that case, since patterning is required, a desired pattern is obtained by photolithography etching or the like.
Manufacturing processes for producing the electro-mechanical conversion element, for example, after the steps (Ia) to (Ie) or after (IIa) to (IId) An insulating protective film can be provided for the purpose of preventing destruction. As a material for the insulating protective film, an inorganic film such as a silicon oxide film, a silicon nitride film, or a silicon oxynitride film, or an organic film such as a polyimide or parylene film is preferable. As a method for manufacturing the insulating protective film, the insulating protective film can also be manufactured by using a CVD method, a sputtering method, a spin coating method, or a screen printing method.

As described above, from the precursor solution for the electromechanical conversion film on the non-permeable substrate that has been inspected by the surface energy inspection method of the present invention and determined that the measurement allowable value is equal to or higher than a preset set allowable value. The electromechanical conversion film can be manufactured by applying the ink.
An electromechanical conversion element having a lower electrode composed of a non-permeable substrate and an upper electrode facing the lower electrode, and sandwiching the electromechanical conversion film between the lower electrode and the upper electrode If this is used, a liquid discharge head can be formed. An ink jet recording apparatus can be configured by providing such a liquid discharge head.
An electro-mechanical conversion element having an electromechanical conversion film manufactured by inspection by the surface energy inspection method of the present invention can obtain stable ink discharge characteristics even when continuously discharged. When PZT is used, the same characteristics (piezoelectric constant) as the ceramic sintered body can be maintained. If a droplet discharge head is configured using such an electro-mechanical conversion element, it has excellent discharge stability and durability, so it can be applied to printers used in offices, personal printers, MFPs, and other droplet discharge devices. Application to three-dimensional molding technology is also possible.
Hereinafter, the liquid discharge head and the ink jet recording apparatus will be described in detail.

[Liquid discharge head]
The configuration of a liquid discharge head using the electromechanical transducer of the present invention is shown in FIGS.
FIG. 8 is a schematic cross-sectional view illustrating a configuration example of a droplet discharge head including an electro-mechanical conversion element.
In the liquid discharge head shown in FIG. 8, an electromechanical conversion film 43 is provided on the platinum group electrode 42 and the oxide electrode 41 of the lower electrode, and the upper electrode 44 on which, for example, platinum is formed on the electromechanical conversion film 43. Are stacked to constitute the electromechanical transducer 40.
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.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited by these examples, and these examples are appropriately modified without departing from the gist of the present invention. Those are also within the scope of the present invention.

[Example 1]
In accordance with the manufacturing process including the steps (Ia) to (Ie) described above, a PZT film was formed according to the process shown in the schematic diagram of FIG. At that time, after the surface modification step (Ic), after performing the “surface energy inspection (wetting test) of the wettability pattern” of the present invention shown in FIG. The inkjet coating process (Id) was performed. In the inkjet coating process of (Id), an electro-mechanical conversion film was formed on the second electrode having a wettability pattern by an inkjet method (discharge droplets by an inkjet device).
First, a thermal oxide film was formed on a silicon wafer, and a platinum film (thickness 250 nm) was formed as a first electrode by sputtering with an adhesion layer (TiO ₂ film) interposed (Ia).
Next, in order to form a patterned second electrode on the first electrode, first, a SrRuO ₃ film (film thickness: 50 nm) is formed by sputtering, and then a photoresist is spin-coated on the SrRuO ₃ film. A film was formed. After making this photoresist film into a resist pattern by ordinary photolithography, an inspection pattern and a coating pattern as shown in FIG. 6 were formed by dry etching (Ib).
The dimension of the coating pattern formed as shown in FIG. 6 was a rectangular shape of 1000 μm × 50 μm, and the dimension of the inspection pattern was a rectangular shape of 500 μm × 50 μm. The inspection pattern was provided with an inclination of about θ = 5 ° with respect to the coating pattern.
Next, surface modification treatment of the first electrode [only the surface of the first electrode (Pt) was modified to form a hydrophobic region (FIG. 4B)] was performed (Ic).
Specifically, a silicon wafer on which a wettability pattern (inspection pattern and coating pattern) as shown in FIG. 6 was formed was immersed in an alkanethiol solution, then washed and dried with ethanol, and SAM treatment was performed. As the alkanethiol solution, a solution in which alkanethiol [CH ₃ (CH ₂ ) ₁₁ -SH] was adjusted to a concentration of 0.1 mmol / l in ethanol and dissolved was used.
The contact angle of water on the SAM-treated platinum film (first electrode: low surface energy region B) is 100 ° or more, whereas the SrRuO ₃ film (second electrode: high surface energy region A). The upper water contact angle is 40 ° or less, and the surface energy contrast between the high surface energy region A and the low surface energy region B, which is necessary for forming the subsequent electro-mechanical conversion film by the inkjet coating process, is sufficient. It was confirmed that it was removed.
After the surface modification, the surface energy inspection (wetting test) of the wettability pattern was performed according to the inspection flowchart shown in FIG. For the wettability test, an ink jet apparatus having the configuration shown in FIG. 7 was used.
For the preparation of a PZT precursor solution (precursor sol ink) to be ejected as droplets in inspection, lead acetate (lead acetate trihydrate), titanium alkoxide (isopropoxide titanium), zirconium alkoxide (isopropoxide) are used as starting materials. Zirconium) was used.
Crystal water of lead acetate was dissolved in methoxyethanol and then dehydrated. The amount of lead was excessive by 10 mol% relative to the stoichiometric composition. This is to prevent crystallinity deterioration due to lead loss during heat treatment in the electro-mechanical conversion film formation process. That is, isopropoxide titanium and isopropoxide zirconium are dissolved in methoxyethanol, followed by alcohol exchange reaction and esterification reaction, and mixed with methoxyethanol solution and 1-nonanol in which lead acetate is dissolved as described above for PZT. A precursor solution was synthesized.
This precursor solution for PZT (precursor sol ink, abbreviated as “ink”) was ejected onto the test pattern shown in FIG. 6 by the ink jet apparatus shown in FIG.
As described with reference to FIG. 1, the target landing position of the droplet intersects with the boundary line (L1) at an angle of θ = 5 ° and is landed as a droplet row (L2). That is, in FIG. 6, droplets are ejected at an angle of θ = 5 ° with respect to the inspection pattern. At that time, the landing interval D of each droplet was set to 40 μm, and the droplet (precursor sol ink) was discharged at 8 pl. As a result, the measurement tolerance was 13 μm.
On the other hand, the range of landing variation calculated from the specifications of the used coating apparatus and inkjet head is ± 35 μm, and the coating pattern width is 50 μm. Therefore, the set allowable value is 35-50 / 2 = 10 (μm). there were. For this reason, the wettability test of this wettability pattern passed.
A surface modification step for forming a wettability pattern on the non-permeable substrate and a droplet wettability pattern by discharging droplets onto the wettability pattern under a condition that the landing position deviation of the droplet is within a set allowable value. The inkjet coating process for forming the copied pattern was repeated. That is, the film thickness obtained by one-time film formation by inkjet coating was set to around 100 nm in order to suppress the generation of cracks. That is, the steps of selective application of PZT precursor, drying, thermal decomposition at 500 ° C., and crystallization treatment (temperature of 750 ° C.) were sequentially repeated to obtain a PZT film having a film thickness of 1.8 μm by a total of 24 repetitions. (Id).
When using SrRuO ₃ as the oxide electrode, the surface energy of the PZT is because of the higher tendency than SrRuO _3, SrRuO ₃ and a sufficient surface energy contrast can take from it is determined in second or subsequent test platinum Omitted.
A third electrode was formed on the formed PZT film.
For the third electrode, first, a SrRuO ₃ film (film thickness: 50 nm) and a Pt film (150 nm) are formed by sputtering, and then a photoresist is formed on the Pt film by a spin coating method. After forming a resist pattern by lithography, it was produced by dry etching (Ie).

[Example 2]
The step of forming the second electrode made of the conductive oxide of (Ib) performed in Example 1 is not provided, and the entire surface of the metal (Pt) of (IIa) is treated with a SAM film to obtain a low surface energy region. An electro-mechanical conversion film was formed in the same manner as in Example 1 except that the wettability pattern (high surface energy region A) was formed via the step B.
That is, in accordance with the manufacturing process including the steps (IIa) to (IId) described above, a PZT film was formed according to the process shown in the schematic diagram of FIG. At that time, after the surface modification step (IIb), after performing the “surface energy inspection (wetting test) of the wettability pattern” of the present invention shown in FIG. The inkjet coating process (IIc) was performed.
Specifically, a thermal oxide film was formed on a silicon wafer, and a platinum film (thickness 250 nm) was formed as a first electrode by sputtering with an adhesion layer (TiO ₂ film) interposed.
The silicon wafer on which the platinum film was formed was immersed in an alkanethiol solution, then washed with ethanol and dried to perform SAM treatment to form a low surface energy region B (IIa). As the alkanethiol solution, the same solution as in Example 1 was used.
Next, a photoresist was formed on the SAM by spin coating. After making this photoresist film into a resist pattern by ordinary photolithography, an inspection pattern and a coating pattern as shown in FIG. 6 were formed by dry etching (IIb).
The contact angle of water on the platinum film (low surface energy region B) after SAM treatment is 100 ° or more, whereas the inspection pattern and coating pattern (Pt: high surface energy) formed by etching treatment The contact angle of water on the region A) is 40 ° or less, and the surface energy of the high surface energy region A and the low surface energy region B necessary for forming the subsequent electro-mechanical conversion film by the ink jet coating process. It was confirmed that sufficient contrast was obtained.
After the surface modification, the surface energy inspection (wetting test) of the wettability pattern was performed according to the inspection flowchart shown in FIG. The inspection method is exactly the same as in the first embodiment.
As described with reference to FIG. 1, the target landing position of the droplet intersects with the boundary line (L1) at an angle θ and is landed as a droplet row (L2). In FIG. 6, droplets are ejected at an angle θ with respect to the inspection pattern. At that time, the landing interval D of each droplet was set to 40 μm, and the droplet (precursor sol ink) was discharged at 8 pl. As a result, the measurement tolerance was 15 μm.
On the other hand, the range of landing variation calculated from the specifications of the used coating apparatus and inkjet head is ± 35 μm and the coating pattern width is 50 μm, so the setting allowable value determined from 35-50 / 2 = 10 (μm) Met. For this reason, the wettability test of this wettability pattern passed.
A surface modification step for forming a wettability pattern on the wet substrate, and a droplet was ejected onto the wettability pattern under the condition that the landing position deviation of the liquid droplet was within a set allowable value, and imitating the wettability pattern The inkjet coating process for forming the pattern was repeated. That is, the film thickness obtained by one-time film formation by inkjet coating was set to around 100 nm in order to suppress the generation of cracks. That is, the steps of selective application of PZT precursor, drying, thermal decomposition at 500 ° C., and crystallization treatment (temperature of 750 ° C.) were sequentially repeated to obtain a PZT film having a film thickness of 1.8 μm by a total of 24 repetitions. (IIc).
An upper electrode was formed on the formed PZT film.
For the upper electrode, a Pt film (thickness 150 nm) is first formed by sputtering, and then a photoresist is formed on the Pt film by a spin coat method, and a resist pattern is formed on the photoresist film by ordinary photolithography. It was fabricated by dry etching (IId)).

From the results of Example 1 and Example 2, the surface energy inspection method for wettability pattern according to the present invention was carried out using a surface modification step for forming a wettability pattern on a non-permeable substrate and droplets on the wettability pattern. The surface energy of the wettability pattern can be easily inspected, and the wettability pattern in the inkjet coating process It was confirmed that the tolerance of the landing position deviation of the droplet when forming a pattern following the above can be obtained, and the accuracy of ink jet coating can be improved.
The electro-mechanical transducers of Example 1 and Example 2 produced by the manufacturing process incorporating the surface energy inspection method of the wettability pattern of the present invention have excellent wettability pattern accuracy. A piezoelectric thin film (for example, PZT) could be laminated stably.

The electromechanical conversion element provided with the electromechanical conversion film (for example, PZT film) manufactured by the manufacturing process in which the surface energy inspection method of the wettability pattern of the present invention is introduced does not deteriorate the displacement amount even when continuously discharged. Sufficiently suppressed, stable ink ejection characteristics can be obtained, and characteristics (piezoelectric constant) equivalent to those of a ceramic sintered body are maintained, and an ink jet apparatus (for example, an ink jet printer or MFP) having excellent durability is used. It has been confirmed that the present invention is useful for digital printing apparatuses, offices, personal printers, MFPs, and the like.
The wettability pattern surface energy inspection method of the present invention includes a surface modification step for forming a wettability pattern on a non-permeable substrate, and a droplet is ejected onto the wettability pattern to imitate the wettability pattern. In addition to the electro-mechanical conversion element manufacturing process, for various functional films (for example, color filters, metal wiring, etc.) It is also useful.

(Reference in FIG. 7)
DESCRIPTION OF SYMBOLS 200 Base 201 Y-axis drive means 202 Substrate 203 Stage 204 X-axis support member 205 X-axis drive means 208 Ink jet head 210 Supply pipe 211 Z-axis drive means (reference numerals in FIGS. 8 and 9)
10 Nozzle plate 11 Nozzle 20 Pressure chamber substrate (Si substrate)
21 Pressure chamber 30 Diaphragm 40 Electromechanical transducer 41 Oxide electrode 42 Lower electrode (platinum group electrode)
43 Electromechanical conversion film 44 Upper electrode (reference numerals in FIGS. 10 and 11)
81 Recording Device Body 82 Printing Mechanism Unit 83 Paper 84 Paper Feed Cassette 85 Manual Tray 86 Paper Discharge Tray 91 Main Guide Rod 92 Subordinate Guide Rod 93 Carriage 94 Head 95 Ink Cartridge 97 Main Scanning Motor 98 Drive Pulley 99 Driven Pulley 100 Timing Belt 101 Feed roller 102 Friction pad 103 Guide member 104 Transport roller 105 Transport roller 106 Front roller 107 Sub-scanning motor 109 Printing receiving member 111 Transport roller 112 Spur 113 Discharge roller 114 Spur 115 Guide member 116 Guide member 117 Recovery device

JP 2003-121384 A (Patent No. 3975067) JP 2012-124376 A

Claims (12)

Manufacturing process comprising: a surface modification step for forming a wettability pattern on a non-permeable substrate; and an ink jet coating step for forming a pattern following the wettability pattern by discharging droplets on the wettability pattern A surface energy inspection method for wettability patterns introduced in
Forming a wettability pattern composed of a high surface energy region A and a low surface energy region B on a non-permeable substrate by a surface modification step;
A step of ejecting droplets by an ink jet device at at least one position including a portion straddling the boundary line between the high surface energy region A and the low surface energy region B;
A process of observing the form of a droplet landed on at least one position including a portion straddling a boundary line between the high surface energy region A and the low surface energy region B by an image inspection means to obtain the following measurement allowable value;
And a step of determining whether or not the measurement allowable value is equal to or larger than a preset allowable value.
[Measurement tolerance]: A droplet landed on at least one position including a portion straddling the boundary line between the region A and the region B by the surface energy contrast between the region A and the region B is completely moved from the region B to the region A. An allowable value set based on the shortest distance from the center of the droplet at the allowable landing position to the boundary line between the area A and the area B.   2. The surface energy inspection method for a wettability pattern according to claim 1, wherein the image inspection means is an optical microscope.   The surface energy inspection method for a wettability pattern according to claim 1 or 2, wherein a boundary line between the high surface energy region A and the low surface energy region B is linear. In the process of ejecting droplets by the inkjet device, the droplets are ejected in a straight line across the boundary line (L1) between the high surface energy region A and the low surface energy region B to form a droplet row (L2). When landing and making the droplet row, the landing interval D and / or θ in the following formula (1) is controlled to determine the difference in distance from the droplet center to the boundary line (L1) of each droplet. The surface energy inspection method for a wettability pattern according to any one of claims 1 to 3, wherein adjustment is performed.
Difference in distance from the center of each droplet to the boundary line (L1) = D × sin θ (1)
[In the formula (1), D represents the landing interval of each droplet, and θ represents the crossing angle between the boundary line (L1) and the droplet row (L2). ]   The surface of the non-permeable substrate is composed of a noble metal surface and a non-noble metal surface, the low surface energy region B is formed by surface modification of the noble metal surface, and the high surface energy region A is formed by the non-noble metal surface. The surface energy inspection method for a wettability pattern according to any one of claims 1 to 4, wherein the wettability pattern is formed.   The surface of the non-permeable substrate is composed of a noble metal surface, the low surface energy region B is formed by surface modification of the noble metal surface, and the high surface energy region A is a part of the low surface energy region B. 5. The surface energy inspection method for a wettability pattern according to any one of claims 1 to 4, wherein the surface energy is partially changed by applying an external stimulus.   The surface energy inspection method for a wettability pattern according to claim 5 or 6, wherein the surface modification of the noble metal surface is performed using a thiol compound.   The surface energy inspection of the wettability pattern according to any one of claims 1 to 7, wherein the manufacturing process into which the surface energy inspection method of the wettability pattern is introduced is a manufacturing process of an electro-mechanical conversion element. Method.   A precursor for an electromechanical conversion film is formed on a non-permeable substrate that has been inspected by the surface energy inspection method according to claim 1 and determined that the measurement allowable value is equal to or greater than a preset allowable value. An electromechanical conversion film produced by applying an ink made of a body solution. An electromechanical conversion element comprising the electromechanical conversion film according to claim 9,
An electric machine having a lower electrode made of the non-permeable substrate and an upper electrode facing the lower electrode, wherein the electromechanical conversion film is sandwiched between the lower electrode and the upper electrode Conversion element.   A liquid discharge head comprising the electromechanical transducer according to claim 10.   An ink jet recording apparatus comprising the liquid discharge head according to claim 11.