JP2006053452A - Pattern forming method for polymer insulating film and electronic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pattern forming method for an insulating film by which the insulating film can be simply and easily patterned and which ensures less damage to the constituent elements of a device, and to provide an electronic device. <P>SOLUTION: The pattern forming method for a polymer insulating film comprises: a step of forming a polymer precursor layer 12 by coating the top of a substrate 11 with a polymer insulating film material containing a heat polymerizable polymer precursor material; a step of selectively polymerizing the polymer precursor layer 12 with a heating means; and a step of removing the unpolymerized polymer precursor material with a solvent which does not dissolve the polymer of the polymerized part 13, but dissolves the unpolymerized part 14. The electronic device has a contact hole formed in a polymer insulating film by the method. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a polymer insulating film pattern forming method and an electronic device.

As electronic devices such as arithmetic elements are required to be highly integrated like VLSI and ULSI in recent years, the importance of multi-layered elements and fine wiring technology has increased.
FIG. 12 is a diagram illustrating an example of an arithmetic circuit. p-ch and n-ch respectively indicate a transistor using a hole transport material and a transistor using an electron transport material. The arithmetic circuit of FIG. 12 is an example of a NOT arithmetic circuit, but other OR, NAND, NOR, XOR arithmetic circuits, etc. are integrated via the interlayer insulating film 201 as illustrated in FIG. 13A. In addition, a fine wiring electrode 202 is connected on the interlayer insulating film 201, whereby a highly integrated arithmetic element is configured. As is well known, the transistor 203 in this arithmetic element includes a gate electrode 204, a gate insulating film 205, a source electrode 206, a drain electrode 207, and a semiconductor 208 (FIG. 13B).
FIG. 14 is a diagram illustrating an example of a display device. In the display device 209, a display element 213 is provided between the substrate 210 and the second substrate 212 including the transparent conductive film 211. A TFT (electronic element) 214 is arranged on the non-display side, a pixel electrode 215 is formed on the interlayer insulating film 216, and a voltage is applied between the pixel electrode 215 and the transparent conductive film 211 to display the pixel electrode 215. The element 214 displays an image. In order to perform high-definition display, the pixel electrode 215 needs to be finely formed on the interlayer insulating film 216. Reference numerals 204, 205, 206, 207, and 208 denote the gate electrode 204, the gate insulating film 205, the source electrode 206, the drain electrode 207, and the semiconductor 208, as in FIG. 13.

Here, as can be seen from FIGS. 13 and 14, the interlayer insulating film is formed not only on the electrode material but also on the semiconductor material layer when there is a transistor. On the other hand, in recent years, an element using an organic material as a semiconductor material has been attracting attention because of its merit in manufacturing such as cost reduction and ease of enlargement and the possibility of function not found in inorganic materials. For example, according to Patent Document 1, a field effect transistor using an organic semiconductor material whose carrier mobility is changed by a physical external stimulus such as light or heat is proposed.
In some cases, this organic semiconductor material is dissolved in an organic solvent having a small polarity such as toluene, THF, xylene, and formed into a coating film. When an interlayer insulating film is formed using such a solvent, an organic semiconductor material layer is formed on the organic semiconductor material layer. On the other hand, it has a problem of causing damage.

On the other hand, for example, Patent Document 2 uses SiO ₂ as an interlayer insulating film material. Although SiO ₂ has a high withstand voltage and is a highly reliable material as an interlayer insulating film, it is generally necessary to form it by a vacuum film forming process such as sputtering. There's a problem. Since this problem is the same when Si ₃ N ₄ , SiON, or the like is used, a material that can be formed by a coating process such as spin coating and has a high withstand voltage has been desired. In the interlayer insulating film, it is necessary to reduce the parasitic capacitance that causes wiring delay. Since this wiring delay is a cause of lowering the operating frequency of an arithmetic element such as an LSI, a material having a dielectric constant smaller than that of SiO ₂ (ε = less than 3.9) has been desired.

Contact holes are formed in the interlayer insulating film in order to make electrical contact between the wiring layers.
Patent Document 3 discloses a photolithography method using a photosensitive resist. First, a metal thin film is provided on the insulating film, a photosensitive resist is applied thereon, and a pattern is formed by photolithography. Next, the metal thin film is dry-etched, and the insulating film is subjected to reactive ion etching using the patterned metal thin film as a mask to form a contact hole in the insulating film.
For example, Patent Document 4 discloses a technique for forming a contact hole by exposure with a photomask using photosensitive polyimide.
Since the above method uses a light source with high energy such as ultraviolet rays for exposure, there is a risk of damaging components other than the insulating film. Particularly in the case of an element using an organic material as a component such as a wiring material, an electrode material, or a semiconductor material, these characteristics may be adversely affected.

JP-A-7-86600 Japanese Patent Laid-Open No. 5-36627 Japanese Patent Laid-Open No. 7-94490 JP-A-9-55426

  SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide an insulating film pattern forming method and an electronic device that can easily pattern an insulating film and cause little damage to constituent elements of the device.

In the first aspect of the present invention, a polymer insulating film material containing a heat-polymerizable polymer precursor material is coated on a base to form a polymer precursor layer, and the polymer precursor layer is selectively formed by heating means. And a step of removing unpolymerized polymer precursor material using a solvent that does not dissolve the polymer after polymerization and dissolves the polymer precursor layer. This is a pattern forming method.
According to this structure, the insulating film can be easily patterned, and a method for forming a pattern of the insulating film with less damage to the constituent elements of the element is provided.

A second aspect of the present invention is the polymer insulating film pattern forming method according to the first aspect, wherein the heating means is means using infrared rays.
According to this configuration, since the heating means is infrared, high-definition patterning can be performed.

According to a third aspect of the present invention, the positive pattern of the infrared absorbing material is formed on the infrared transmitting material to prepare a mask, and the polymer precursor layer is irradiated with infrared through the mask. A method for forming a pattern of a polymer insulating film according to a second aspect.
According to this configuration, since infrared rays are irradiated through a mask in which a positive pattern is formed with an infrared absorbing material, a large amount of high-definition patterns can be easily formed.

According to a fourth aspect of the present invention, a mask is prepared by forming a negative pattern of an infrared ray shielding material on an infrared ray transmissive material, and infrared rays are irradiated on the polymer precursor layer through the mask. The method for forming a pattern of a polymer insulating film according to the second aspect.
According to this configuration, since infrared rays are irradiated through the mask on which the light-shielding negative pattern is formed, a higher definition pattern can be easily formed.

A fifth aspect of the present invention is the polymer insulating film pattern forming method according to the second aspect, wherein the heating unit is a unit that scans and irradiates an infrared laser.
According to this configuration, since the infrared laser is scanned and irradiated, the pattern of the polymer insulating film can be further easily formed.

6th of this invention has the process of apply | coating an infrared-absorbing material on this polymer precursor layer, and forming an infrared-absorbing material layer after forming the said polymer precursor layer. 5. The polymer insulating film pattern forming method according to any one of 5 above.
According to this configuration, since the infrared ray absorbing material layer is formed on the polymer precursor layer to form the infrared ray absorbing material layer, the pattern of the polymer insulating film can be formed with less energy.

A seventh aspect of the present invention is the polymer insulating film pattern forming method according to the sixth aspect, wherein the infrared absorbing material layer is patterned.
According to this configuration, since the infrared absorbing material layer is patterned, it is possible to more easily form the pattern of the polymer insulating film.

An eighth aspect of the present invention is the polymer insulating film pattern forming method according to any one of the first to fifth aspects, wherein the polymer insulating film material contains an infrared absorbing material.
According to this configuration, since the polymer insulating film material contains the infrared absorbing material, the pattern of the polymer insulating film can be formed with less energy.

A ninth aspect of the present invention is the polymer insulating film pattern forming method according to the eighth aspect, wherein the infrared absorbing material is present in the polymer precursor layer with a distribution in a film thickness direction.
According to this configuration, since the infrared absorbing material exists in the polymer precursor layer with a distribution in the film thickness direction, it is possible to easily pattern the polymer insulating film with good insulating characteristics.

A tenth aspect of the present invention is the polymer insulating film pattern forming method according to the first aspect, wherein the heating means is a thermal head.
According to this configuration, since the heating means is a thermal head, the pattern of the polymer insulating film can be more easily formed.

The eleventh aspect of the present invention is the polymer insulating film pattern forming method according to any one of the first to tenth aspects, wherein the polymer precursor material is a polyamic acid.
According to this configuration, since the polymer precursor layer is a polyamic acid, it is possible to easily form a pattern of a polymer insulating film with good insulating properties.

In the twelfth aspect of the present invention, the application of the polymer insulating film material is performed using a solvent containing a polymer precursor, and the solvent is a solvent compatible with water at an arbitrary ratio. The polymer insulating film pattern forming method according to any one of the first to eleventh aspects.
According to this configuration, since the solvent is compatible with water at an arbitrary ratio, the pattern of the polymer insulating film can be formed without damaging the substrate and the constituent elements.

According to a thirteenth aspect of the present invention, there is provided a wiring pattern forming method, wherein the groove of the wiring portion is formed by the polymer insulating film pattern forming method according to any one of the first to twelfth aspects.
According to this configuration, a wiring pattern can be easily formed.

A fourteenth aspect of the present invention is an electronic device characterized in that a contact hole is formed in a polymer insulating film by the polymer insulating film pattern forming method according to any one of the first to tenth aspects.
According to this configuration, it is possible to provide an electronic element in which multilayer wiring is performed by a simple method.

The fifteenth aspect of the present invention is the electronic element according to the fourteenth aspect, wherein a component of the electronic element includes an organic semiconductor material.
According to this configuration, it is possible to provide an electronic device in which multilayer wiring using an organic semiconductor material is performed by a simple method.

According to a sixteenth aspect of the present invention, there is provided a display device comprising the electronic device according to the fourteenth or fifteenth aspect.
According to this configuration, it is possible to provide a display element that is simpler and less expensive than the conventional one.

  ADVANTAGE OF THE INVENTION According to this invention, an insulating film can be patterned easily and the pattern formation method and electronic device of an insulating film with little damage with respect to the component of an element can be provided.

  The first feature of the present invention is that a polymer insulating film material containing a heat-polymerizable polymer precursor material is applied on a base to form a polymer precursor layer, and the polymer precursor layer is formed by heating means. A polymer insulation comprising: a step of selectively polymerizing; and a step of removing unpolymerized polymer precursor material using a solvent that does not dissolve the polymer after polymerization and dissolves the polymer precursor layer. A method for forming a film pattern. In addition, the polymer precursor material as used in the field of this invention means the material which becomes a polymer by superposition | polymerization, and includes a monomer, an oligomer, an intermediate body, etc.

  FIG. 1 is a diagram for explaining an example of the method of the present invention. As shown in FIG. 1A, a polymer insulating film material containing a polymer precursor material is applied to the surface of a substrate 11 to form a polymer precursor layer 12. Although nothing is configured on the surface of the substrate 11 in FIG. 1, electronic elements such as wirings, resistors, capacitors, diodes, and transistors may be formed on the surface of the substrate 11. Next, as shown in FIGS. 1B and 1C, the polymer precursor layer 12 is selectively polymerized by heating with a heating means (not shown) to form a polymerized portion 13 and an unpolymerized portion 14. Finally, as shown in FIG. 1 (d), the polymerized polymer is not dissolved, and a solvent for dissolving the unpolymerized portion is used to dissolve and remove the polymer precursor in the unpolymerized portion, thereby completing the patterning of the polymer insulating film. . Compared to the patterning of insulating materials using a photosensitive insulating film material as used in the past, thermopolymerizable polymer precursors are easier to handle and do not require equipment like the yellow room. Simple patterning can be realized. Examples of the thermopolymerizable polymer precursor include polyamic acid derivatives, acrylic acid derivatives, and phenol derivatives.

  The second feature of the present invention is to use infrared rays as the heating means. Since infrared rays are used as the heating means, patterning with high definition can be performed. Examples of the infrared heating method include an infrared lamp and an infrared laser.

The third feature of the present invention is that a positive pattern of an infrared absorbing material is formed on an infrared transmitting material to produce a mask, and the polymer precursor layer is irradiated with infrared through the mask. A large amount of the same pattern can be easily produced, and a high-definition pattern can be easily formed by increasing the definition of the mask.
FIG. 2 is a diagram for explaining a process of irradiating infrared rays on the polymer precursor layer through a mask in which a positive pattern of the infrared absorbing material is formed. As in the previous FIG. 1, a polymer insulating film material containing a polymer precursor material is applied to the surface of the substrate 11 to form a polymer precursor layer 12 (FIG. 2 (a)), as shown in FIG. 2 (b). As described above, a positive pattern is formed on the light-transmitting substrate 15 by the infrared absorbing material 16. A photomask 17 on which a positive pattern is formed on a substrate 11 on which a polymer precursor layer 12 as shown in FIG. 2A is formed, and an infrared absorbing material 16 is formed on the polymer precursor layer 12 as shown in FIG. Lay it in contact and irradiate with infrared rays. As a result, the infrared absorbing material 16 of the photomask 17 absorbs infrared rays to generate heat, selectively heats the polymer precursor layer 12, and forms a polymerized portion 13 and an unpolymerized portion 14 as shown in FIG. To do. At this time, in order to prevent the polymer precursor layer 12 from being polymerized by infrared rays that are directly irradiated through the photomask 17, the infrared absorption material provided on the photomask is more than the infrared absorption efficiency of the polymer insulating film material. It is necessary that the infrared absorption efficiency is high. The portion overlapping the positive portion (infrared absorbing material portion) of the photomask 17 of the polymer precursor layer 12 is polymerized by irradiation with infrared rays. Finally, the pattern of the polymer insulating film as shown in FIG. 2D is obtained by washing with a solvent that dissolves the polymer precursor.
As the infrared absorbing material, a dye or a pigment can be used. As dyes, azo dyes, nitro dyes, nitrosolo dyes, stilbene azo dyes, ketoimine dyes, triphenylmethane dyes, xanthene dyes, acridine dyes, quinoline dyes, methine / polymethine dyes, thiazole dyes, indamine / indophenol dyes, azine dyes Oxazine dye, thiazine dye, sulfur dye, aminoketone dye, oxyketone dye, anthraquinone dye, indigoid dye, phthalocyanine dye and the like. Examples of pigments include inorganic pigments composed of compounds such as metal oxides and salts, nitro pigments, dye lake lakes, azo lakes, insoluble azo, monoazo, disazo, condensed azo, azo pigments such as benzimidazolone, phthalocyanine, anthraquinone, Mention may be made of organic pigments such as perylene, quinacridone, dioxazine, isoindolinone, quinophthalone, isoindoline, azomethine, pyrrolopyrrole. Furthermore, carbon black can also be used suitably.

A fourth feature of the present invention is that a mask is formed by forming a negative pattern of an infrared light shielding material on an infrared transparent material, and infrared rays are irradiated on the polymer precursor layer through the mask. . Compared with the method of FIG. 2, since the mask side does not generate heat, the pattern accuracy can be increased.
FIG. 3 is a diagram for explaining a process of irradiating infrared rays through a mask on which a light-shielding negative pattern is formed. As in the previous FIG. 1, a polymer insulating film material containing a polymer precursor material is applied to the surface of the substrate 11 to form a polymer precursor layer 12 (FIG. 3 (a)), as shown in FIG. 3 (b). In this manner, a negative pattern is formed on the light transmissive substrate 15 by the light shielding material 18. The substrate 11 on which the polymer precursor layer 12 as shown in FIG. 3A is formed is overlaid with a photomask 19 on which a negative pattern is formed and irradiated with infrared rays, and as shown in FIG. An unpolymerized portion 14 is formed. At this time, as shown in FIG. 3B, it is preferable that the light-shielding material 18 is overlapped so as to be in contact with the polymer precursor layer 12 because blurring of a pattern due to infrared wrap-around can be prevented. As a result, the polymer precursor layer 12 generates heat and is selectively heated by the infrared rays transmitted through the photomask 19. Finally, the pattern of the polymer insulating film as shown in FIG. 3D is obtained by washing with a solvent that dissolves the polymer precursor.

  The fifth feature of the present invention is that the heating means scans and irradiates an infrared laser. FIG. 4 is a view showing an example of means for scanning and irradiating an infrared laser. Infrared rays from the infrared laser 20 are shaped by an optical system such as a lens 21, deflected by a deflection mechanism 22 such as a polygon mirror or a galvanometer mirror, and then condensed on the polymer precursor layer 12 by a lens 23. The scanning speed is determined from the wavelength and intensity of the infrared laser, the infrared absorption characteristics of the polymer precursor layer 12, and the like. In the case of selective polymerization using a laser, it is not necessary to prepare a photomask as shown in FIGS. 2 and 3, so that it is possible to more easily form a pattern of a polymer insulating film.

The sixth feature of the present invention is that it has a step of forming an infrared absorbing material layer by applying an infrared absorbing material after forming the polymer precursor layer. Since the infrared absorption efficiency is improved by the infrared absorbing material layer, it is possible to efficiently absorb the irradiated infrared rays and heat the polymer precursor layer, so that the pattern of the polymer insulating film can be formed with less energy. .
FIG. 5 is a diagram for explaining a process of forming an infrared absorbing material layer by applying an infrared absorbing material. An infrared absorbing material layer 24 is provided on the polymer precursor layer 12 as shown in FIG. Next, infrared mask exposure or selective irradiation with an infrared laser as described above is performed, and the infrared absorbing material layer is selectively heated as shown in FIG. Although FIG. 5B shows a method using the negative photomask 19, a method using a positive mask or infrared laser scanning may be used. As shown in FIG. 5C, the polymer precursor layer 12 is selectively polymerized to form the polymerized portion 13 and the unpolymerized portion 14, and finally the infrared absorbing material layer 24 and the unpolymerized portion 14 are removed. A polymer insulating film patterned as shown in FIG. 5 (d) is obtained. As the infrared absorbing material, dyes and pigments as described above can be used.

A seventh feature of the present invention is that the infrared absorbing material layer is patterned. Since the infrared absorbing material layer is patterned, infrared irradiation may be performed on the entire surface, and the pattern formation of the polymer insulating film can be performed more easily.
FIG. 6 is a diagram showing an example of patterning the infrared absorbing material layer. As shown in FIG. 6A, an infrared absorbing material layer 24 is formed in a positive pattern on the surface of the polymer precursor layer 12. For the formation of the infrared absorbing material layer 24, an existing patterning method such as etching, screen printing, or an ink jet method can be used. From the viewpoint of simplicity, a printing method such as screen printing or an ink jet method is preferable. Next, the infrared absorption layer generates heat by irradiating infrared rays, and the polymer precursor layer 12 is selectively polymerized as shown in FIG. 6B to form the polymerized portion 13 and the unpolymerized portion 14, and finally the infrared ray is irradiated. By removing the absorbing material layer 24 and the unpolymerized portion 14, a polymer insulating film patterned as shown in FIG. 6C is obtained.

The eighth feature of the present invention is that the polymer insulating film material contains an infrared absorbing material.
Since the polymer insulating film material contains an infrared absorbing material, the irradiated infrared rays are efficiently converted into heat, so that the pattern of the polymer insulating film can be formed with less energy. When the polymer precursor layer 12 is directly heated by infrared rays, heat generation is small depending on the infrared absorption rate of the polymer precursor layer 12, and it may take time for the polymerization or may be insufficient. According to the eighth feature of the present invention, a pattern can be stably formed regardless of the polymer insulating film material. As the infrared absorbing material, dyes and pigments as described above can be used, but a material that does not impair the insulating characteristics is preferable because it remains in the polymer insulating film. In the polymer precursor layer 12, the proportion of the infrared absorbing material is preferably 5 to 50% by weight.

  A ninth feature of the present invention is that the infrared absorbing material exists in the polymer precursor layer with a distribution in the film thickness direction. A polymer precursor layer containing an infrared absorbing material is formed, and the infrared absorbing material is distributed in the film thickness direction at the time of film formation, so that the infrared absorbing material layer and the polymer insulating film material can be formed in a single film formation. The layer can be formed with or without an interface, and the process can be simplified. In addition, when the distribution of the polymer insulating material and the infrared absorbing material is different in the film thickness direction, the layer with more polymer insulating film material has a better insulating property, so the infrared absorbing material is evenly distributed Insulation characteristics can be improved compared to The distribution can be formed before the solvent evaporates during drying, for example, by differentiating the polarities and molecular weights of the infrared absorbing material and the polymer insulating film material.

  The tenth feature of the present invention is that the heating means is a thermal head. The resolution of the thermal head may be higher than the resolution of the polymer insulating film pattern to be formed. In the case of the method using the thermal head, the definition is lower than the method using the infrared rays described above. However, if the pattern to be formed is not so high definition, the polymer insulating film has a simpler structure than the method using the infrared rays. Can be patterned.

  An eleventh feature of the present invention is that the polymer precursor material is a polyamic acid. As the polymer precursor material, various materials can be used as described above. However, when a polyamic acid represented by the following formula is used as the polymer precursor, particularly good insulating properties can be obtained. Here, A and B are aromatic compounds, aliphatic compounds or cyclic compounds. Polyimide is obtained by polymerizing polyamic acid. Polyimide has good insulating properties and is suitable for use in an interlayer insulating film. In the formula, n is an integer and the number of repeating units.

A twelfth feature of the present invention is that the polymer insulating film material is applied using a solvent containing a polymer precursor, and the solvent is compatible with water at an arbitrary ratio. That is.
This feature makes it possible to form a polymer insulating film without damage even when a material that is easily dissolved in an organic solvent is provided on the surface on which the polymer insulating film is formed. Examples of the solvent in the present invention include alcohol solvents such as ethanol, methanol, and propanol, glycol solvents such as ethylene glycol, propylene glycol, and diethylene glycol, cellosolv solvents such as 2-methoxyethanol, 2-ethoxyethanol, and 2-butoxyethanol. Is mentioned. In the present invention, the solvent compatible with water at an arbitrary ratio is desirably 30 vol% or more with respect to the total solvent used in the polymer precursor layer. More desirably, 90 vol% or more is desirable.

  A thirteenth feature of the present invention is a wiring pattern forming method for forming a groove in a wiring portion by the polymer insulating film pattern forming method. As a wiring pattern forming method, a method shown in FIG. 7 is known. First, as shown in FIG. 7A, a groove 26 according to the wiring pattern is formed in the insulating film 25 for forming the wiring pattern on the substrate 11. Next, as shown in FIG. 7B, a conductive material 27 is formed on the entire surface of the insulating film 25 including the groove 26. Finally, the surface is polished to obtain a conductive pattern 28 buried in the groove as shown in FIG. This method is generally called a damascene method, and a groove is generally formed using a photosensitive insulating film material. By forming the groove corresponding to FIG. 7A by the method of the present invention, the groove can be formed more easily. FIG. 8 is a diagram for explaining a groove forming method according to the present invention. First, a polymer insulating film material is formed on the entire surface of the substrate 11 and heated to form a polymer insulating film 29 as shown in FIG. Next, as shown in FIG. 8B, a polymer precursor layer 12 is formed and selectively polymerized by the above-described method to form a polymerized portion 13 and an unpolymerized portion 14 (FIG. 8C). . Finally, the unpolymerized portion 14 is removed to obtain the groove pattern shown in FIG.

  A fourteenth feature of the present invention is an electronic device in which a contact hole is formed in a polymer insulating film by the polymer insulating film pattern forming method. By providing holes in the polymer insulating film by the above-described pattern forming method of the polymer insulating film and filling the conductive material, conduction between the upper and lower sides of the polymer insulating film can be established, and multilayer laminated wiring becomes possible.

  A fifteenth feature of the present invention is that the constituent elements of the electronic element include an organic semiconductor material. Examples of the electronic element including an organic semiconductor material as a constituent element include an organic diode, an organic transistor, an organic EL, an organic solar battery, and an organic photosensor. When these organic electronic devices are formed, multilayer wiring is generally used to increase the degree of integration. However, by using the present invention, electronic devices using organic semiconductor materials can be easily formed into multilayer wiring. . In addition, if the solvent used for applying the polymer insulating film material is compatible with water at an arbitrary ratio, damage to the organic semiconductor material is minimized. Can be suppressed.

A sixteenth feature of the present invention resides in a display device configured using the electronic element. Thereby, it is possible to provide a display device that is simpler and less expensive than conventional ones.
FIG. 9 is a diagram for explaining an example of the display device of the present invention. As the display device, methods such as liquid crystal, electrophoresis, and organic EL can be used. In the display device of FIG. 9, the display device 30 is provided with a display element 34 between a substrate 31 and a second substrate 33 having a transparent conductive film 32. A TFT (electronic element) 35 is disposed on the non-display side, a pixel electrode 36 is formed on the interlayer insulating film 37, and a voltage is applied between the pixel electrode 36 and the transparent conductive film 32 to display. The element 34 displays an image. Reference numerals 204, 205, 206, 207, and 208 denote the gate electrode 204, the gate insulating film 205, the source electrode 206, the drain electrode 207, and the semiconductor 208, as in FIG. 13.
Since the liquid crystal display element is driven by an electric field, the power consumption is small, and since the driving voltage is low, the driving frequency of the TFT can be increased, which is suitable for large-capacity display. Examples of liquid crystal display elements include TN, STN, guest-host type, polymer-dispersed liquid crystal (PDLC), etc. PDLC is preferable in that a bright white display can be obtained with a reflection type. .
Further, an electrophoretic display device can also be employed as the display device. The electrophoretic display element is composed of a dispersion liquid in which particles exhibiting a first color (for example, white) are dispersed in a coloring dispersion medium exhibiting a second color. The particles exhibiting the first color are contained in the coloring dispersion medium. By being charged, the position in the dispersion medium can be changed by the action of an electric field, and the color to be exhibited thereby changes. According to this display method, it is possible to display brightly and with a wide viewing angle, and since it has a display memory property, it is preferably used particularly from the viewpoint of power consumption.
By using microcapsules in which the dispersion is wrapped with a polymer film, the display operation is stabilized and the display device can be easily manufactured. Microcapsules can be produced by a known method such as a coacervation method, an in-situ polymerization method, or an interfacial polymerization method. Titanium oxide is particularly preferably used as the white particles, and surface treatment or compounding with other materials is performed as necessary. Examples of the dispersion medium include aromatic hydrocarbons such as benzene, toluene, xylene, naphthenic hydrocarbons, aliphatic hydrocarbons such as hexane, cyclohexane, kerosene, and paraffinic hydrocarbons, trichloroethylene, tetrachloroethylene, trichlorofluoroethylene, odor It is preferable to use an organic solvent having a high resistivity such as halogenated carbon (hydrocarbon) such as ethyl halide, fluorine-containing ether compound, fluorine-containing ester compound, or silicone oil. In order to color the dispersion medium, oil-soluble dyes such as anthraquinones and azo compounds having desired absorption characteristics are used. A surfactant or the like may be added to the dispersion for stabilization of dispersion.
In addition, since the organic EL element is a self-luminous type, vivid full color display can be performed. In addition, since the EL layer is a very thin organic thin film, it has high flexibility and is particularly suitable for being formed on a flexible substrate.

The present invention will be further described below with reference to examples.
Example 1
The transistor array 100 shown in FIG. 10 was fabricated according to the following procedure.
First, the gate electrode 204 was formed on the substrate 31 by vapor deposition. Next, polyimide was spin-coated as the gate insulating film 205 and baked to form a film. Gold was deposited and patterned by photolithography to form a source electrode 206, a drain electrode 207, and a wiring. Further, pentacene, which is the organic semiconductor 208, was vapor deposited by mask. Further, polyamic acid was applied to the surface as a polymer insulating film material and dried. The used polyamic acid has a structure represented by the following formula. Next, a positive pattern was formed on the glass substrate with an ink containing carbon black, and the positive photomask shown in FIG. 2 was produced. This positive photomask was superimposed on a substrate on which a polyamic acid film was formed so that the infrared absorbing material was in contact with the polymer insulating film material, and infrared rays were irradiated by an infrared lamp. Next, unpolymerized polyamic acid was removed by butyl cellosolve to form a contact hole to form an interlayer insulating film 37. Finally, gold was mask-deposited as the pixel electrode 36 to produce a transistor array provided with the pixel electrode. Through the above steps, the contact hole can be formed easily and easily compared to the method of forming the contact hole of the interlayer insulating film using the photosensitive material.

Example 2
The same procedure as in Example 1 was performed until the coating and drying steps of the polymer insulating material were completed. Next, a thin layer of carbon black was formed as an infrared absorbing material layer on the polymer insulating film material layer. Next, the negative photomask which formed the negative pattern with the chromium on the glass substrate was applied, and infrared rays were irradiated. The unpolymerized polyamic acid was removed with butyl cellosolve to form an interlayer insulating film 37 having a contact hole. Finally, gold was deposited to form display electrodes. The TFT array could be easily formed by the above process. Compared to the method of forming a contact hole in an interlayer insulating film using a photosensitive material, the contact hole can be formed easily and easily.

The display device shown in FIG. 11 was produced as follows.
Microcapsules 40 containing titanium oxide particles 38 and isopar 39 colored with oil blue are mixed in a PVA aqueous solution and applied onto a polycarbonate substrate 41 which is a second substrate on which a transparent electrode made of ITO is formed. A layer composed of the capsule 40 and the PVA binder 42 was formed. This substrate was bonded to the TFT array substrate manufactured in Example 2.
A scanning signal driver IC was connected to the bus line connected to the gate electrode, and a data signal driver IC was connected to the bus line connected to the source electrode. When the screen was switched every 0.5 seconds, a good still image could be displayed.
As described above, a display device having favorable characteristics can be manufactured by a simple method.

Comparative Example 1
In the display device of Example 3, an interlayer insulating film and a contact hole were formed using photosensitive polyimide. Others are the same as in the third embodiment. Since the interlayer insulation film and contact holes are formed using photosensitive polyimide, a yellow room is prepared, and film formation, exposure using a photomask, and development are performed with care to avoid unnecessary exposure during film formation. It was necessary to do.

Example 4
The transistor array shown in FIG. 10 was fabricated according to the following procedure.
First, a gate electrode was formed on the substrate by vapor deposition. Next, the same polyamic acid as in Example 1 was applied to the entire surface and heated to form a polyimide film. Next, polyamic acid was applied to the polyimide film surface. Next, a concave pattern was formed by irradiating infrared rays with a photomask in which a negative pattern of the source electrode, drain electrode and wiring was formed with carbon black and washing with butyl cellosolve. Next, after depositing gold on the entire surface, the source electrode, the drain electrode, and the wiring were formed by polishing. Further, polyamic acid was applied to the surface as a polymer insulating film material layer and dried. Next, a positive pattern was formed on the glass substrate with ink containing carbon black, and the positive photomask of FIG. 2 was produced. This positive photomask was placed on a substrate on which a polyamic acid film was formed, and infrared rays were irradiated with an infrared lamp. Next, unpolymerized polyamic acid was removed by butyl cellosolve to form contact holes in the interlayer insulating film. Finally, a transistor array provided with pixel electrodes was produced by mask vapor deposition of gold as pixel electrodes. The TFT array could be easily formed by the above process.

  ADVANTAGE OF THE INVENTION According to this invention, an insulating film can be patterned easily and the pattern formation method and electronic device of an insulating film with little damage with respect to the component of an element are provided.

It is a figure for demonstrating an example of the method of this invention. It is a figure for demonstrating the process of irradiating infrared rays on a polymer precursor layer through the mask in which the positive pattern of the infrared rays absorption material was formed. It is a figure for demonstrating the process of irradiating infrared rays through the mask in which the light-shielding negative pattern was formed. It is a figure which shows an example of the means to scan and irradiate an infrared laser. It is a figure for demonstrating the process of apply | coating an infrared-absorbing material and forming an infrared-absorbing material layer. It is a figure which shows the example which patterned the infrared rays absorption material layer. It is a figure for demonstrating the formation method of the conventional wiring pattern. It is a figure for demonstrating the formation method of the groove | channel in this invention. It is a figure for demonstrating an example of the display apparatus of this invention. 2 is a diagram for explaining a transistor array of Example 1. FIG. FIG. 10 is a diagram for explaining a display device according to a second embodiment. It is a figure which shows the example of an arithmetic circuit. It is a figure which shows the example of the highly integrated arithmetic element. It is a figure which shows an example of a display apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Board | substrate 12 Polymer precursor layer 13 Superposition | polymerization part 14 Unpolymerization part 15 Light transmissive board | substrate 16 Infrared absorption material 17, 19 Photomask 24 Infrared absorption material layer 30 Display apparatus 31 Substrate 32 Transparent conductive film 33 2nd board | substrate 34 Display element 35 TFT (electronic device)
36 pixel electrode 37 interlayer insulating film 40 microcapsule 100 electronic element array 204 gate electrode 205 gate insulating film 206 source electrode 207 drain electrode 208 semiconductor

Claims (16)

  A step of forming a polymer precursor layer by applying a polymer insulating film material containing a thermopolymerizable polymer precursor material on a base, a step of selectively polymerizing the polymer precursor layer by heating means, and a polymerization And a step of removing unpolymerized polymer precursor material using a solvent that does not dissolve the later polymer and dissolves the polymer precursor layer.   The method for forming a pattern of a polymer insulating film according to claim 1, wherein the heating means is means using infrared rays.   3. The polymer insulation according to claim 2, wherein a positive pattern of an infrared absorbing material is formed on an infrared transparent material to produce a mask, and infrared rays are irradiated on the polymer precursor layer through the mask. A film pattern forming method.   3. The polymer according to claim 2, wherein a negative pattern of an infrared light shielding material is formed on an infrared transparent material to produce a mask, and infrared rays are irradiated on the polymer precursor layer through the mask. Insulating film pattern forming method.   3. The method for forming a pattern of a polymer insulating film according to claim 2, wherein the heating unit is a unit that scans and irradiates an infrared laser.   6. The method according to claim 1, further comprising a step of forming an infrared absorbing material layer by applying an infrared absorbing material on the polymer precursor layer after forming the polymer precursor layer. Pattern forming method for polymer insulating film.   The method for forming a pattern of a polymer insulating film according to claim 6, wherein the infrared absorbing material layer is patterned.   6. The polymer insulating film pattern forming method according to claim 1, wherein the polymer insulating film material contains an infrared absorbing material.   9. The method for forming a pattern of a polymer insulating film according to claim 8, wherein the infrared absorbing material is present in the polymer precursor layer with a distribution in the film thickness direction.   The method for forming a pattern of a polymer insulating film according to claim 1, wherein the heating means is a thermal head.   The method for forming a pattern of a polymer insulating film according to claim 1, wherein the polymer precursor material is a polyamic acid.   2. The application of the polymer insulating film material is performed using a solvent containing a polymer precursor, and the solvent is a solvent compatible with water at an arbitrary ratio. The pattern formation method of the polymer insulating film in any one of -11.   A method for forming a wiring pattern, comprising forming a groove in a wiring portion by the method for forming a pattern of a polymer insulating film according to any one of claims 1 to 12.   An electronic device comprising a polymer insulating film formed with a contact hole by the polymer insulating film pattern forming method according to claim 1.   The electronic device according to claim 14, wherein a component of the electronic device includes an organic semiconductor material. A display device comprising the electronic device according to claim 14.

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