JPH11245426A - Manufacture of ink-jet recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing an ink jet recorder in which serious troubles, e.g. production of residues through mechanomechical polishing or nonejection of ink due to burrs, are eliminated. SOLUTION: After respective layers are laminated on a first substrate 1 of Si, a thick film polyimide layer 2 of polymer based insulation film is formed thereon and patterned. Since irregularities appear on the surface when the thick film layer 2 is thermally set, mechanochemical polishing is employed. At the time of polishing, slurry may be left or the edge of the thick film layer 2 may be burred. Ultrasonic cleaning is performed using a weak alkaline surfactant in order to remove residual slurry principally. Cleaning is performed furthermore using an ethanol amine based organic solvent in order to remove burr principally. Subsequently, it is bonded to a second substrate 3 and cut off.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a first substrate and a second substrate.
More particularly, the present invention relates to a method for manufacturing an ink jet recording apparatus comprising joining a substrate, and more specifically, after forming a thick film layer made of a planarized and patterned polymer-based insulating film on a first substrate, The present invention relates to a method for manufacturing an ink jet recording apparatus joined to a second base.

[0002]

2. Description of the Related Art FIG. 2 is a sectional view showing an example of a thermal type ink jet recording apparatus, and FIG. 3 is a front view of the same. In the figure, 1 is a first base, 2 is a thick film layer, 3 is a second base.
4, a glaze layer, 5 a heating resistor, 6 a heating resistor protection layer, 7 a wiring, 8 a bonding pad, 9 an ink supply port, 10 a liquid chamber, 11 an ink flow path, 12 and
13 is a cutting position and 14 is a bubble. The first base 1 is
The glaze layer 4 is formed on the surface of, for example, Si. On the glaze layer, a heating resistor 5 serving as an ink ejecting element, and an electric circuit such as a wiring 7 and a drive circuit for sending an electric signal to the heating resistor 5 for driving are formed. Further, a bonding pad 8 and the like for receiving an image signal and power to be recorded from outside are formed.
Further, a heating resistor protection layer 6 is formed on the heating resistor 5. Of course, various layers other than these layers may be formed.

Further, a thick film layer 2 made of a polymer-based insulating film is formed thereon, and a portion, for example, on the heating resistor 5 is removed by patterning to form a concave portion. Further, the portion where the bonding pad 8 is arranged is also removed. Then, the thick film layer 2 is thermally cured, for example.

On the other hand, through holes are formed by etching or the like in a second substrate 3 also made of Si to provide an ink supply port 9 and a liquid chamber 10, and a heating resistor 5 formed on the first substrate 1 is formed. Is formed by etching or the like.

[0005] Then, the first substrate 1 on which the thick film layer 2 is formed and the second substrate 3 are aligned and joined so as to sandwich the thick film layer 2. Then, the cutting position 12 and the cutting position 1
By cutting at 3, the ink jet recording apparatus is formed. At this time, the first base 1 and the second base 3 are also cut at the cutting position 12, and the nozzles for discharging the ink by opening the ink flow path 11 are formed as shown in FIG. At the cutting position 13, only the second base 3 is cut to expose the bonding pad 8. The ink jet recording apparatus thus formed is mounted on, for example, a heat sink or the like, and the bonding pad 8 and the wiring board are electrically connected by wire bonding or the like.

The ink is supplied from a not-shown ink tank to a liquid chamber 10 and an ink flow path 11 via an ink supply port 9. When a signal or power of an image to be recorded is supplied from the main body via the bonding pad 8, the electric circuit formed on the first base 1 is temporarily connected to the heating resistor 5 via the wiring 7. A signal is sent, and the heating resistor 5 generates heat. The generated heat is transmitted to the ink via the heat-generating resistor protection layer 6, and the ink undergoes film boiling to generate bubbles 14. The pressure at which the bubble 14 grows causes the ink flow path 11 to grow.
The ink inside is pushed out of the nozzles and flies as ink droplets. The ink droplet lands on a recording medium such as paper to form a recording pixel. An image is formed on a recording medium by controlling a signal to be sent to the heating resistor 5 according to a given image signal.

In an ink jet recording apparatus having such a structure that the thick film layer 2 made of a polymer insulating film is sandwiched between the first base 1 and the second base 3, the thick film directly bonded to the second base 3 is used. The unevenness of the layer 2 becomes a problem. As the polymer-based insulating film, it is desirable to use polyimide as a material that can be patterned into a required geometrical shape and can withstand the temperature cycle of the heating element.
Patterned edges rise or lip (1-8
(Height of microns). FIG. 4 is an enlarged sectional view showing the vicinity of a heating resistor in an example of a conventional ink jet recording apparatus. FIG.
In FIG. 3, the part indicated by a circle in FIG. 3 is enlarged. If the surface of the thick film layer 2 has irregularities as described above, when the first base 1 and the second base 3 are joined, these raised edges and lips come into contact with the second base 3, and Cannot be joined and a gap is generated. For this reason, the ink flow paths 11 are not separated from each other, which may cause a serious obstacle such as crosstalk.

In order to solve such a problem, for example, as disclosed in Japanese Patent Application Laid-Open No.
After thermal curing of the thick film layer 2 and before joining with the second substrate 3, the surface of the thick film layer 2 is subjected to chemical mechanical polishing to be flattened. As a result, the surface of the thick film layer 2 is flattened, and even if the thick film layer 2 is bonded to the second substrate 3, it is possible to avoid a serious obstacle such as a gap.

FIG. 5 is an enlarged sectional view showing the vicinity of a heating resistor in an example of a conventional ink jet recording apparatus in which a thick film layer is polished. In the figure, 21 is a residue and 22 is a burr. As described in the above-mentioned literature, when the surface of the thick film layer 2 is subjected to chemical mechanical polishing, the fragments or abrasives (slurries) of the thick film layer 2 which are shaved off at that time are concave portions. It accumulates on the heating resistor 5 and becomes a residue 21. Such a residue 21 is 1% of the area of the heating resistor 5.
Amounts exceeding 0% are reached. Further, burrs 22 that have not been removed are generated at the corners of the thick film layer 2. If the bonding with the second substrate 3 is performed while such residue 21 and burrs 22 remain, the heat generated in the heating resistor 5 due to the residue 21 is not well transmitted to the ink during recording. Further, the growth of the air bubbles 14 generated on the heating resistor 5 is hindered by the burrs 22, which causes a non-uniform amount of ink droplets to be ejected or a serious obstacle that the ink droplets are not ejected. There was a problem.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has a serious problem of non-ejection of ink droplets due to residues or burrs generated by chemical mechanical polishing of a thick film layer. It is an object of the present invention to provide a method of manufacturing an ink jet recording apparatus in which no trouble occurs.

[0011]

SUMMARY OF THE INVENTION The present invention is directed to a method of ultrasonic cleaning in a solution containing a neutral or weakly alkaline surfactant after chemical-mechanical polishing of the outer surface of a thick film layer. It is characterized by washing with an amine-based organic solution or ultrasonic washing in a solution containing a neutral or weakly alkaline surfactant, and then successively washing with an ethanolamine-based organic solution. By ultrasonic cleaning in a solution containing a neutral or weakly alkaline surfactant, residues generated during polishing can be removed. Further, by washing with an ethanolamine-based organic solution, it is possible to remove burrs generated in the thick film layer together with residues generated during polishing. By such cleaning, residues and burrs generated by chemical mechanical polishing can be removed, so that the amount of ink droplets does not change, and problems such as ink droplets not being ejected may occur. Absent. Of course, since the first base and the second base are satisfactorily bonded, there is no possibility of causing serious trouble due to poor bonding.

[0012]

FIG. 1 is a process chart showing an embodiment of a method for manufacturing an ink jet recording apparatus according to the present invention. Here, description will be made on the assumption that the ink jet recording apparatus shown in FIGS. 2 and 3 is manufactured. As in the conventional manufacturing method, in S31, a glaze layer 4, a heating resistor 5 serving as an ink ejection element, and an electric signal are sent to the heating resistor 5 on the first base 1 made of, for example, Si. An electric circuit such as a wiring 7 or a driving circuit for driving;
Each layer such as a heating resistor protection layer 6 is laminated on the heating resistor 5. Of course, various layers other than these layers may be formed. For example, the heating resistor 5 and the electric circuit may be replaced by C
An insulating film such as a VD oxide film or silicon nitride can be formed, and these can be inactivated. Also, when each layer is laminated, it is appropriately patterned.

In S32, after the respective layers are stacked,
For example, the polyimide thick film layer 2 made of a polymer insulating film is applied by a spin coating method or the like. Then, by photolithography or the like, for example, a portion on the heating resistor 5 and a portion where the bonding pad 8 is arranged is removed by patterning.

Next, in S33, heat treatment is performed at 350 ° C. for 120 minutes. The heat treatment cures the polyimide thick film layer 2, but the edges of the pattern are raised, and a change in the film thickness due to the unevenness of the underlying layer appears on the surface. Therefore, chemical mechanical polishing is performed in S34. The polishing conditions for this chemical mechanical polishing include, for example, a table speed of 80 rpm and a carrier speed of 40 rpm.
m, down pressure 5.0 psi, back pressure 3.0 psi. Of course, it is not restricted to this condition. As the slurry used at this time, an alumina-based slurry (specifically, R-90 manufactured by Rodale, average particle size 0.8 to 1.4 μm) can be used.

After the chemical mechanical polishing, before the first substrate 1 is dried, ultrasonic cleaning (for example, about 10 minutes at room temperature) is performed in step S35 with a 1% solution of a weak alkaline surfactant. Thereafter, it is washed with water (for example, for about 10 minutes).
This ultrasonic cleaning with a 1% solution of a weakly alkaline surfactant mainly removes slurry residues. FIG. 6 is an explanatory diagram showing an example of the remaining state of the slurry with respect to the concentration of the surfactant and the cleaning time. In the figure, ○ indicates that there was no slurry residue, Δ indicates that some slurry may remain, and x indicates that slurry remains. Here, ultrasonic cleaning is performed for 10 minutes using a 1% solution surrounded by a thick frame in FIG. 6, but even if the cleaning is performed for a shorter time or the concentration of the solution is low, it is necessary to sufficiently remove the slurry residue. Can be. When a surfactant solution having a low concentration is used, the washing time may be increased, and when it is desired to perform the washing in a short time, the concentration of the solution may be increased. However, the effect of removing the slurry residue does not change much even when the concentration of the solution is 3% or more. Conversely, the cleaning is performed in a state where the aluminum bonding pad 8 is exposed. Therefore, when cleaning is performed with a high-concentration weakly alkaline surfactant, aluminum is dissolved by the surfactant and the bonding pad 8 is removed. Another obstacle appears, such as a decrease in film thickness. Therefore, the concentration of the weakly alkaline surfactant is desirably 3% or less. Also, by utilizing the dissolution of this aluminum with a weakly alkaline surfactant, slurry residues stuck on the bonding pad 8 and the like can be removed.

Next, in S36, the substrate is washed with an ethanolamine-based organic solvent at 50 ° C. for 10 minutes, and then washed with water (for example, about 10 minutes). Washing with an ethanolamine-based organic solvent also has the effect of removing residues,
The burrs of the polyimide generated on the thick film layer 2 mainly by polishing are removed. The ethanolamine-based organic solvent is used as, for example, a resist stripper. This ethanolamine-based resist stripping solution has a property that the stripping characteristics rapidly increase when the processing temperature is increased. Generally, the resist is stripped at a temperature of 90 to 110 ° C. However, if the polyimide thick film layer 2 is treated at this temperature, problems such as a decrease in the film thickness occur. for that reason,
It was confirmed that the temperature of 50 ° C. or less was optimal for removing burrs generated by polishing. If the treatment is performed at 50 ° C. or less, the surface of the thick film layer 2 is etched by about 0.1 μm. At this time, the slurry, dust and the like fixed on the surface of the thick film layer 2 are simultaneously removed.

By performing the washing in S35 and S36 in this manner, slurry residues, burrs, and the like generated by polishing are removed. Here, only one of the cleaning in S35 and the cleaning in S36 may be performed depending on the remaining state of the slurry after polishing and the state of occurrence of burrs.

On the other hand, in another step, a through-hole serving as a liquid chamber 10 is formed in the second substrate 3 made of, for example, Si by etching or the like, and the heating resistor 5 formed on the first substrate 1 is formed in the second substrate 3. The corresponding ink channel 11 is formed by etching or the like.

In S37, an adhesive is applied to both or one of the first substrate 1 on which the thick film layer 2 has been formed and polished and cleaned, and the second substrate 3 formed in a separate step. Is applied, the first base 1 and the second base 3 are aligned, and the first base 1 and the second base 3 are joined to sandwich the thick film layer 2 therebetween. At this time, the surface of the thick film layer 2 is slightly etched by the ethanolamine-based organic solvent in S36, and the surface is roughened at that time, so that the adhesion area is increased and the adhesion is improved. can do. Then, in S38, the sheet is cut into individual ink jet recording devices by cutting at the cutting position.

FIG. 7 is an enlarged sectional view showing the vicinity of a heating resistor of an ink jet recording apparatus manufactured according to an embodiment of the present invention. Compared with the conventional ink jet recording apparatus shown in FIGS. 4 and 5, the thick film layer 2 and the second substrate 3 are better bonded, and the residue 21 and the burr 22 are present. Absent. Therefore, the heat generated by the heating resistor 5 is efficiently transmitted to the ink, and the growth of the bubbles 14
As a result, the ink droplets can be ejected in a predetermined amount and the printing can be performed satisfactorily.

The present invention can be applied to the manufacture of any ink jet recording apparatus in which a first substrate and a second substrate are joined with a thick film layer interposed therebetween, and the structure thereof is shown in FIGS. It is not limited to those shown in
The present invention can be applied to various flow path structures, for example, a roof shooter type ink jet recording apparatus, and an ink jet recording apparatus using a driving method other than the thermal type using the heating resistor 5.

[0022]

As is apparent from the above description, according to the present invention, the thick film layer of polyimide, which is a polymer insulating film, is subjected to chemical mechanical polishing to flatten its surface, Immediately after polishing, appropriate cleaning is performed, and residues and burrs generated during polishing are satisfactorily removed, so that the first substrate and the second substrate are separated, and ink droplets due to the residues and burrs are removed. There is an effect that it is possible to provide an ink jet recording apparatus in which a serious trouble such as a shortage of an amount or a non-ejection of an ink droplet is prevented.

[Brief description of the drawings]

FIG. 1 is a process chart showing one embodiment of a method for manufacturing an ink jet recording apparatus of the present invention.

FIG. 2 is a cross-sectional view illustrating an example of a thermal type inkjet recording apparatus.

FIG. 3 is a front view showing an example of a thermal type ink jet recording apparatus.

FIG. 4 is an enlarged cross-sectional view near a heating resistor in an example of a conventional ink jet recording apparatus.

FIG. 5 is an enlarged sectional view showing the vicinity of a heating resistor in an example of an ink jet recording apparatus in which a conventional thick film layer is polished.

FIG. 6 is an explanatory diagram showing an example of the remaining state of the slurry with respect to the concentration of the surfactant and the cleaning time.

FIG. 7 is an enlarged cross-sectional view of the vicinity of a heating resistor of the inkjet recording apparatus manufactured according to the embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... 1st base | substrate, 2 ... thick film layer, 3 ... 2nd base | substrate, 4 ... Glaze layer, 5 ... Heating resistor, 6 ... Heating resistor protection layer, 7
... wiring, 8 ... bonding pad, 9 ... ink supply port,
10: liquid chamber, 11: ink flow path, 12, 13: cutting position, 14: bubble, 21: residue, 22: burr.

Claims (5)

[Claims] 1. A method of manufacturing an ink jet recording apparatus comprising joining a first base and a second base, wherein an electric circuit is formed on the first base and a polymer-based insulating film is formed on the first base. A thick film layer, patterning the thick film layer so as to form at least one depression in the thick film layer, curing the thick film layer, and chemically and mechanically forming an outer surface of the thick film layer. An ink jet recording apparatus wherein the outer surface of the thick film layer is flattened by polishing, and ultrasonic cleaning is performed in a solution in which a neutral or weakly alkaline surfactant is diluted, and bonded to a second substrate. Manufacturing method. 2. A method of manufacturing an ink jet recording apparatus comprising joining a first base and a second base, wherein an electric circuit is formed on the first base and a polymer-based insulating film is formed on the first base. A thick film layer, patterning the thick film layer so as to form at least one depression in the thick film layer, curing the thick film layer, and chemically and mechanically forming an outer surface of the thick film layer. A method for manufacturing an ink jet recording apparatus, comprising: polishing an outer surface of the thick film layer to flatten the surface; cleaning the organic layer with an ethanolamine-based organic solvent; and bonding the substrate to a second substrate. 3. A method of manufacturing an ink jet recording apparatus comprising joining a first base and a second base, wherein an electric circuit is formed on the first base and a polymer-based insulating film is formed on the first base. A thick film layer, patterning the thick film layer so as to form at least one depression in the thick film layer, curing the thick film layer, and chemically and mechanically forming an outer surface of the thick film layer. Polishing is performed to flatten the outer surface of the thick film layer, ultrasonic cleaning is performed in a solution in which a neutral or weakly alkaline surfactant is diluted, and then cleaning is performed using an ethanolamine-based organic solvent. A method for manufacturing an ink jet recording apparatus, comprising: 4. The method according to claim 1, wherein the concentration of the solution obtained by diluting the neutral or weakly alkaline surfactant used for performing the ultrasonic cleaning is 3% or less. A method for manufacturing the ink jet recording apparatus according to the above. 5. The ink-jet recording according to claim 2, wherein the washing with the ethanolamine-based organic solvent is performed at a liquid temperature of the ethanolamine-based organic solvent of 50 ° C. or less. Device manufacturing method.