JP2015041636A - Organic semiconductor element and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic semiconductor element capable of suppressing oxidation of a source electrode, a drain electrode, and data wiring at etching of an organic semiconductor layer by using vacuum ultraviolet light and that has a high electrical reliability, and to provide a method of manufacturing the same.SOLUTION: An organic semiconductor element comprises: a base material; a source electrode, a drain electrode, and data wiring formed on the base material and containing a metal material; an organic semiconductor layer formed so as to cover the source electrode, the drain electrode, and the data wiring; and a contact hole penetrating through the organic semiconductor layer, and formed so as to reach the drain electrode. A thickness of the drain electrode in a contact hole region where the contact hole is formed, and a thickness of the drain electrode in an organic semiconductor layer coating region covered with the organic semiconductor layer, are equal to each other.

Description

  The present invention relates to a method for manufacturing an organic semiconductor element in which an organic semiconductor layer is patterned using vacuum ultraviolet light, and an organic semiconductor element obtained by the manufacturing method.

  In recent years, semiconductor transistors typified by TFTs tend to expand their applications with the development of display devices. A semiconductor transistor functions as a switching element when electrodes are connected via a semiconductor material.

  Conventionally, inorganic semiconductor materials such as silicon, gallium arsenide, and indium gallium arsenide have been used as semiconductor materials for semiconductor transistors. In recent years, a semiconductor transistor using such an inorganic semiconductor material is also used for a TFT array substrate for a display of a liquid crystal display element that has been widely spread.

  On the other hand, organic semiconductor materials are also known as semiconductor materials. Organic semiconductor materials have the advantages of being able to increase the area at a lower cost than inorganic semiconductor materials, being able to be formed on a flexible plastic substrate, and being stable against mechanical impacts. Therefore, research is being actively conducted on organic semiconductor materials, assuming application to next-generation display devices such as flexible displays typified by electronic paper.

  When manufacturing an organic semiconductor transistor using an organic semiconductor material, it is usually necessary to form an organic semiconductor layer in a pattern. Conventionally, as a method for forming an organic semiconductor layer in a pattern, a photoresist method has been mainly used as described in Patent Document 1, for example. However, the photoresist method is excellent in that the organic semiconductor layer can be patterned with high accuracy, but has a problem that the productivity is poor because the process is complicated.

  In order to solve such a problem, Patent Document 2 proposes a method of forming an organic semiconductor layer using an inkjet method. The inkjet method is a method in which a small amount of ink is ejected to a predetermined position using an inkjet head, and is excellent in that a fine patterned organic semiconductor layer can be formed with high productivity.

  Further, Patent Document 3 discloses a method of etching an organic semiconductor layer using vacuum ultraviolet light. This method is an excellent method in that a higher-definition organic semiconductor layer can be formed with high productivity. The vacuum ultraviolet light is also referred to as vacuum ultra violet or VUV.

  By the way, in an organic semiconductor transistor, since a source electrode and a drain electrode are connected through an organic semiconductor layer, the electrode material used for the source electrode and the drain electrode has high electrical connectivity with the organic semiconductor layer. It is preferable. It is known that a metal material is suitably used as this electrode material.

  When etching the organic semiconductor layer using the vacuum ultraviolet light described above, the organic semiconductor layer is generally etched so that the organic semiconductor layer is formed in a channel region between the source electrode and the drain electrode. Therefore, in the bottom contact type organic semiconductor transistor, when the source electrode and the drain electrode are made of a metal material, the source electrode and the drain electrode are oxidized by the influence of the vacuum ultraviolet light when the organic semiconductor layer is etched, and the electrode performance is deteriorated. There is a problem of disconnection or disconnection. The oxidation due to the influence of vacuum ultraviolet light is a phenomenon that occurs not only in the source electrode and the drain electrode but also in the data wiring and the like.

  Therefore, in Patent Document 4, in order to prevent the source electrode and the drain electrode from being oxidized and deteriorated by the vacuum ultraviolet light irradiated when the organic semiconductor layer is etched, oxygen source is not formed on the source electrode and the drain electrode. It has been proposed to form an electrode protection layer having a shielding property.

  Patent Document 5 is not related to a method for etching an organic semiconductor layer using vacuum ultraviolet light, but it is intended to protect an electrode wiring already formed at the time of patterning the organic semiconductor layer by a laser ablation method. It has been proposed that the organic semiconductor layer be formed so as to completely cover the source electrode, the drain electrode, and the wiring.

JP 2006-58497 A JP 2003-347552 A JP 2008-244262 A JP 2012-216564 A Japanese Patent No. 4742021 Special table 2008-524839 gazette

However, in patent document 4, it is necessary to form an electrode protective layer on a source electrode and a drain electrode, and the number of processes will increase.
Further, in the laser ablation method, as described in Patent Document 5, the electrode located under the organic semiconductor layer is also damaged, so that not only the organic semiconductor layer but also the source electrode, the drain electrode, and the Wiring is also removed. Therefore, when the laser ablation method is used, it is difficult to form the organic semiconductor layer in the channel region between the source electrode and the drain electrode in the bottom contact type organic semiconductor transistor. This point is also described in Patent Document 6, for example. Therefore, the laser ablation method does not cause a problem that the source electrode and the drain electrode are oxidized at the time of patterning the organic semiconductor layer.

  In an organic semiconductor transistor, for example, an interlayer insulating layer is formed on an organic semiconductor layer, a source electrode, a drain electrode, a gate electrode, a gate insulating layer, and a wiring, a pixel electrode is formed on the interlayer insulating layer, and a contact The pixel electrode and the drain electrode are electrically connected through the hole. As a method for forming a contact hole, for example, Patent Document 5 discloses a laser etching method. However, in the laser etching method, it is technically difficult to remove only the organic semiconductor layer and the interlayer insulating layer without removing the drain electrode. Therefore, when a contact hole is formed on the drain electrode, the laser etching method damages the drain electrode in the same manner as the laser ablation described above, so that the thickness of the drain electrode is reduced at the contact hole portion. As a result, there is a problem that poor contact between the pixel electrode and the drain electrode occurs, resulting in a decrease in electrical reliability.

  In Patent Document 5, a photolithography method is also disclosed as a method for forming a contact hole. However, usually, when the planarization insulating film is patterned by photolithography, the organic semiconductor layer is not patterned at the same time. That is, when patterning the planarization insulating film by photolithography, it is impossible to simultaneously pattern the organic semiconductor layer in the contact hole portion. In that case, since the pixel electrode and the drain electrode are connected in a state where the organic semiconductor layer remains in the contact hole portion, a contact failure occurs. In addition, when patterning a planarization insulating film by photolithography, it is thought that the organic semiconductor layer in the contact hole portion can be washed with an organic solvent or the like, but the organic solvent soaks into the in-plane direction of the organic semiconductor layer. This is not realistic because the organic solvent penetrates to the channel region and lacks reliability.

  The present invention has been made in view of the above circumstances, and can suppress oxidation of a source electrode, a drain electrode, and a data wiring during etching of an organic semiconductor layer using vacuum ultraviolet light, and has an electrical reliability. The main object of the present invention is to provide an organic semiconductor element having a high thickness and a method for producing the same.

  In order to solve the above problems, the present invention includes a base material, a source electrode, a drain electrode and a data wiring formed on the base material and including a metal material, and the source electrode, the drain electrode and the data wiring. The drain of the contact hole region having the organic semiconductor layer formed to cover and the contact hole formed so as to penetrate the organic semiconductor layer and reach the drain electrode. Provided is an organic semiconductor element characterized in that the thickness of the electrode is equal to the thickness of the drain electrode in the organic semiconductor layer covering region covered with the organic semiconductor layer.

  According to the present invention, since the organic semiconductor layer is formed on the source electrode, the drain electrode and the data wiring including the metal material, the source electrode and the drain electrode are used when the organic semiconductor layer is etched using vacuum ultraviolet light. Further, it is possible to suppress oxidation of the data wiring. Therefore, it is possible to suppress a decrease in electrode performance and disconnection, and to improve electrical connectivity between the source and drain electrodes and the organic semiconductor layer. According to the present invention, since the drain electrode has the same thickness in the contact hole region and the organic semiconductor layer covering region, when an external input / output electrode such as a pixel electrode is connected to the drain electrode through the contact hole, Contact failure between the electrode and the external input / output electrode can be suppressed. Therefore, an organic semiconductor element with high electrical reliability can be obtained.

  In the said invention, it is preferable that the said organic-semiconductor layer is formed so that a part of external connection terminal and an inspection terminal may be covered. The organic semiconductor layer can enhance adhesion between a part of the external connection terminal and the inspection terminal and an interlayer insulating layer or a gate insulating layer formed on the organic semiconductor layer. Also, when etching an organic semiconductor layer using vacuum ultraviolet light, unlike the laser ablation method, only the organic semiconductor layer is removed without removing the external connection terminals and inspection terminals located under the organic semiconductor layer. Can be removed. Therefore, the organic semiconductor layer can be formed so as to cover a part of the external connection terminal and the inspection terminal.

  According to the present invention, an organic semiconductor layer forming step for forming an organic semiconductor layer and a contact hole reaching the drain electrode are formed on a base material on which a source electrode, a drain electrode and a data wiring containing a metal material are formed. A resist layer is formed on the organic semiconductor layer in the channel region between the source electrode, the drain electrode, and the data wiring other than the contact hole region, and the channel region between the source electrode and the drain electrode. An organic semiconductor layer patterning step of etching the organic semiconductor layer in a portion where the resist layer is not formed by irradiating the resist layer and the organic semiconductor layer with vacuum ultraviolet light, and removing the resist layer; An organic semiconductor device manufacturing method is provided.

  According to the present invention, since the organic semiconductor layer is patterned so that the organic semiconductor layer remains on the source electrode, the drain electrode, and the data wiring including the metal material, the organic semiconductor is used using vacuum ultraviolet light in the organic semiconductor layer patterning step. When the layer is etched, the source electrode, the drain electrode, and the data wiring can be prevented from being oxidized by the vacuum ultraviolet light. Therefore, it is possible to suppress a decrease in electrode performance and disconnection, and to improve electrical connectivity between the source and drain electrodes and the organic semiconductor layer. According to the present invention, since the contact hole is formed by etching the organic semiconductor layer using vacuum ultraviolet light, the thickness of the drain electrode in the contact hole region can be suppressed from being reduced. In the case where an external input / output electrode such as a pixel electrode is connected to the drain electrode through, contact failure between the drain electrode and the external input / output electrode can be suppressed. Therefore, an organic semiconductor element with high electrical reliability can be obtained.

  According to the present invention, since the organic semiconductor layer is formed on the source electrode, the drain electrode, and the data wiring containing the metal material, the source electrode and the drain electrode can be used even when the organic semiconductor layer is etched using vacuum ultraviolet light. In addition, oxidation of the data wiring can be suppressed. Further, since the thickness of the drain electrode is the same in the contact hole region and the organic semiconductor layer coating region, it is possible to suppress contact failure between the drain electrode and the external input / output electrode. Therefore, the electrical reliability of the organic semiconductor element can be improved.

It is a schematic sectional drawing which shows an example of the organic-semiconductor element of this invention. It is a schematic sectional drawing which shows the other example of the organic-semiconductor element of this invention. It is a schematic plan view which shows the other example of the organic-semiconductor element of this invention. It is process drawing which shows an example of the manufacturing method of the organic-semiconductor element of this invention. It is process drawing which shows an example of the manufacturing method of the organic-semiconductor element of this invention. It is a schematic plan view which shows the other example of the organic-semiconductor element of this invention. It is the schematic plan view and sectional drawing which show an example of the wiring in the organic-semiconductor element of this invention, a terminal, and an organic-semiconductor layer. It is a schematic sectional drawing which shows the other example of the organic-semiconductor element of this invention. It is a schematic sectional drawing which shows the other example of the organic-semiconductor element of this invention.

  Hereinafter, the organic semiconductor device and the manufacturing method thereof of the present invention will be described in detail.

A. Organic Semiconductor Element The organic semiconductor element of the present invention covers a base material, a source electrode, a drain electrode, and a data wiring that are formed on the base material and include a metal material, and covers the source electrode, the drain electrode, and the data wiring. The drain electrode in the contact hole region in which the contact hole is formed, and the contact hole formed so as to penetrate the organic semiconductor layer and reach the drain electrode And the thickness of the drain electrode in the organic semiconductor layer covering region covered with the organic semiconductor layer are equal to each other.

  In the following description, “organic semiconductor transistor” refers to a transistor having a gate electrode, a source electrode, a drain electrode, and an organic semiconductor layer. In the present invention, since the organic semiconductor layer is formed on the source electrode and the drain electrode, the organic semiconductor element of the present invention has a bottom gate bottom contact type or top gate bottom contact type organic semiconductor transistor. is there.

The organic semiconductor element of this invention is demonstrated using figures.
FIG. 1 is a schematic cross-sectional view showing an example of the organic semiconductor element of the present invention. As shown in FIG. 1, an organic semiconductor element 1 is formed on a base material 2, a source electrode 3 and a drain electrode 4a that are formed on the base material 2 and contain a metal material, and covers the source electrode 3 and the drain electrode 4a. The organic semiconductor layer 6 formed, the gate insulating layer 7 formed on the organic semiconductor layer 6, the gate electrode 8 formed on the gate insulating layer 7, the gate insulating layer 7 and the organic semiconductor layer 6 are penetrated. The contact hole 12 is formed to reach the drain electrode 4a, and the intermediate electrode 4b is formed on the gate insulating layer 7 and connected to the drain electrode 4a through the contact hole 12. The organic semiconductor layer 6 includes a channel region 21 between the source electrode 3 and the drain electrode 4a, and an electrode region 22 in which the source electrode 3 and the drain electrode 4a are formed other than the contact hole region 23 in which the contact hole 12 is formed. Is arranged. Further, the thickness of the drain electrode 4 a in the contact hole region 23 is equal to the thickness of the drain electrode 4 a in the organic semiconductor layer covering region 24 covered with the organic semiconductor layer 6. This organic semiconductor element 1 has a top gate bottom contact type organic semiconductor transistor.

  FIG. 2 is a schematic cross-sectional view showing another example of the organic semiconductor element of the present invention. As shown in FIG. 2, the organic semiconductor element 1 includes a base material 2, a gate electrode 8 formed on the base material 2, a gate insulating layer 7 formed so as to cover the gate electrode 8, and a gate insulating layer. 7, the source electrode 3 and the drain electrode 4 containing a metal material, the organic semiconductor layer 6 formed so as to cover the source electrode 3 and the drain electrode 4, the organic semiconductor layer 6, and the drain electrode 4 And a contact hole 12 formed so as to reach the above. The organic semiconductor layer 6 includes a channel region 21 between the source electrode 3 and the drain electrode 4, and an electrode region 22 in which the source electrode 3 and the drain electrode 4 are formed other than the contact hole region 23 in which the contact hole 12 is formed. Is arranged. The thickness of the drain electrode 4 in the contact hole region 23 is equal to the thickness of the drain electrode 4 in the organic semiconductor layer covering region 24 covered with the organic semiconductor layer 6. This organic semiconductor element 1 has a bottom gate bottom contact type organic semiconductor transistor.

  FIGS. 3A and 3B are schematic plan views showing other examples of the organic semiconductor element of the present invention. In FIG. 3A, configurations other than the base material, the source electrode, the drain electrode, and the data wiring are omitted. In FIG.3 (b), structures other than a base material and an organic-semiconductor layer are abbreviate | omitted. 3A and 3B, a region where the external input / output electrode 11 such as a pixel electrode connected to the drain electrode through the contact hole is formed is indicated by a one-dot chain line. As shown in FIGS. 3A and 3B, in the organic semiconductor element, a source electrode 3, a drain electrode 4, and a data wiring 5 containing a metal material are formed on a base material 2. An organic semiconductor layer 6 is formed so as to cover the electrode 4 and the data wiring 5. The organic semiconductor layer 6 includes a channel region between the source electrode 3 and the drain electrode 4 and a source electrode 3, a drain electrode 4, and a data wiring 5 other than a contact hole region (not shown) where contact holes are formed. The electrode region 22 is arranged. Although not shown, the thickness of the drain electrode 4 in the contact hole region is equal to the thickness of the drain electrode 4 in the organic semiconductor layer coating region covered with the organic semiconductor layer 6.

  According to the present invention, since the organic semiconductor layer is formed on the source electrode, the drain electrode and the data wiring including the metal material, the source electrode and the drain electrode are used when the organic semiconductor layer is etched using vacuum ultraviolet light. Further, it is possible to suppress oxidation of the data wiring.

Here, the patterning method of the organic semiconductor layer in the present invention will be described. 4 (a) to 4 (g) and FIGS. 5 (a) to 5 (d) are process diagrams showing an example of the method for producing an organic semiconductor element of the present invention. The method for producing the organic semiconductor element of the present invention will be described in detail in the section “B. Method for producing organic semiconductor element”.
When patterning the organic semiconductor layer, first, as shown in FIG. 4B, the organic semiconductor layer 6 is formed on the entire surface of the substrate 2 on which the source electrode 3 and the drain electrode 4a are formed. Next, as shown in FIG. 4C, a resist layer 31 is formed in a pattern on the organic semiconductor layer 6. Subsequently, as shown in FIGS. 4D to 4E, the resist layer 31 and the organic semiconductor layer 6 are irradiated with vacuum ultraviolet light L, so that the organic semiconductor layer 6 in a portion where the resist layer 31 is not formed is exposed. Etch. Thereafter, the resist layer 31 is removed as shown in FIG. Thereby, the organic semiconductor is formed in the channel region 21 between the source electrode 3 and the drain electrode 4a and the electrode region 22 in which the source electrode 3 and the drain electrode 4a other than the contact hole region 23 in which the contact hole 12a is formed. Layer 6 is formed.

In the present invention, since the organic semiconductor layer is formed so as to cover the source electrode, the drain electrode, and the data wiring, the organic semiconductor layer is formed using vacuum ultraviolet light L as shown in FIGS. When etching 6, the source electrode 3 and the drain electrode 4 a are covered with the organic semiconductor layer 6 and the resist layer 31 except for the contact hole region 23. Therefore, the source electrode 3 and the drain electrode 4a can be prevented from coming into contact with oxygen. Furthermore, it is possible to prevent the source electrode 3 and the drain electrode 4a from being irradiated with high-energy light in the ultraviolet region, particularly high-energy vacuum ultraviolet light L. Although data wiring is not shown in FIGS. 4A to 4G and FIGS. 5A to 5D, oxygen contact and vacuum are also applied to the data wiring as in the case of the source electrode and the drain electrode. Irradiation with ultraviolet light can be prevented.
Therefore, in the present invention, when the organic semiconductor layer is etched using vacuum ultraviolet light, the source electrode, the drain electrode, and the wiring can be suppressed from being oxidized, and the electrode performance can be prevented from being lowered or disconnected. is there. Furthermore, the electrical connectivity between the source and drain electrodes and the organic semiconductor layer can be improved.

Note that when the organic semiconductor layer is etched using vacuum ultraviolet light, a part of the drain electrode may come into contact with oxygen or be irradiated with vacuum ultraviolet light in the contact hole region. Is done.
Here, with the intensity of the vacuum ultraviolet light used for etching the organic semiconductor layer, even if the electrode and the wiring are exposed, the progress of oxidation of the electrode and the wiring is slow. However, the oxidation of the electrode and the wiring cannot be made completely zero due to the influence of the uneven irradiation of the vacuum ultraviolet light and the thickness unevenness of the electrode and the wiring. For this reason, oxidation is a problem for electrodes and wirings having a narrow line width. On the other hand, since the width of the contact hole region is wider than the line width of the source electrode and the data wiring, the possibility that the entire contact hole region is oxidized is very low. In addition, when the data wiring is oxidized, it causes a line defect, which has a great influence on the display quality. However, if a part of the drain electrode in the contact hole region is oxidized, only a point defect is generated, which affects the display quality. The impact is small. Therefore, even if a part of the drain electrode in the contact hole region is oxidized, it is not considered a problem.

According to the present invention, since the drain electrode has the same thickness in the contact hole region and the organic semiconductor layer covering region, when an external input / output electrode such as a pixel electrode is connected to the drain electrode through the contact hole, Contact failure between the electrode and the external input / output electrode can be suppressed.
Here, when the contact hole is formed by laser etching after laminating each layer as in the prior art, the drain electrode of the laser irradiated portion is damaged, so that the contact hole region and the region other than the contact hole region are damaged. It is difficult to make the thickness of the drain electrode uniform.
On the other hand, when forming a contact hole by etching an organic semiconductor layer using vacuum ultraviolet light, the energy of vacuum ultraviolet light is lower than that of a laser, so that the drain electrode of the vacuum ultraviolet light irradiated part is etched. Therefore, it is possible to obtain a drain electrode having a uniform thickness in the contact hole region and a region other than the contact hole region.

  Hereinafter, each structure of the organic-semiconductor element of this invention is demonstrated.

1. Organic Semiconductor Layer The organic semiconductor layer in the present invention is formed so as to cover the source electrode, the drain electrode, and the data wiring, and imparts semiconductor characteristics to the organic semiconductor transistor.

The organic semiconductor material used for the organic semiconductor layer is not particularly limited as long as an organic semiconductor layer having desired semiconductor characteristics can be obtained, and organic semiconductor materials generally used for organic semiconductor transistors are used. it can. Examples of such organic semiconductor materials include π-electron conjugated aromatic compounds, chain compounds, organic pigments, and organosilicon compounds. More specifically, low molecular organic semiconductor materials such as pentacene, and polypyrroles such as polypyrrole, poly (N-substituted pyrrole), poly (3-substituted pyrrole), and poly (3,4-disubstituted pyrrole). , Polythiophene, poly (3-substituted thiophene), poly (3,4-disubstituted thiophene), polythiophenes such as polybenzothiophene, polyisothianaphthenes such as polyisothianaphthene, and polychess such as polychenylene vinylene Nylene vinylenes, poly (p-phenylene vinylenes) such as poly (p-phenylene vinylene), polyanilines such as polyaniline and poly (N-substituted aniline), polyacetylenes such as polyacetylene, polyazulenes such as polydiacetylene and polyazulene High molecular organic semiconductor materials such as
There may be only one type of organic semiconductor material, or two or more types.

  The organic semiconductor layer is formed so as to cover the source electrode, the drain electrode, and the data wiring. In this case, the organic semiconductor layer may be formed so as to cover the upper surfaces of the source electrode, the drain electrode, and the data wiring, and to expose the side surfaces of the source electrode, the drain electrode, and the data wiring. An organic semiconductor layer may be formed so as to cover the upper surface and the side surface. In particular, the organic semiconductor layer is preferably formed so as to cover the upper and side surfaces of the source electrode, the drain electrode, and the data wiring. This is because the oxidation of the source electrode, the drain electrode and the data wiring can be effectively suppressed.

As the formation position of the organic semiconductor layer, the source electrode, the drain electrode and the data wiring other than the contact hole region where the organic semiconductor layer is formed in the channel region between the source electrode and the drain electrode and the contact hole is formed are formed. There is no particular limitation as long as it is formed in the electrode region.
Here, the “contact hole region where a contact hole is formed” refers to a contact hole region where a contact hole leading to the drain electrode is formed. For example, as shown in FIG. 5D, when the contact hole 12a and the second contact hole 12b are formed as contact holes, the contact hole region 23 in which the contact hole 12a leading to the drain electrode 4a is formed. .

  Further, as illustrated in FIG. 6, in the organic semiconductor element 1, when a terminal such as an external connection terminal 52 such as an FPC connection part or an inspection terminal 53 is formed around the display part 51 on the base material 2. Although not shown, an organic semiconductor layer may be formed so as to cover a part of the terminal. Specifically, as shown in FIGS. 7A and 7B, when the terminal 55 and the wiring 56 are formed on the substrate 2, the organic semiconductor layer 6 is formed so as to cover the wiring 56. At the same time, it may be formed so as to cover a part of the terminal 55. FIG. 7B is a cross-sectional view taken along line AA in FIG. In this case, the adhesion between the part of the terminal and the interlayer insulating layer or the gate insulating layer formed on the organic semiconductor layer can be improved by the organic semiconductor layer. Also, when etching an organic semiconductor layer using vacuum ultraviolet light, unlike the conventional laser ablation method, only the organic semiconductor layer is removed without removing the terminal located under the organic semiconductor layer. Can do. Therefore, the organic semiconductor layer can be formed so as to cover a part of the terminal. In this case, it is preferable that the external connection terminal and the inspection terminal are partly covered.

  When the organic semiconductor layer is formed so as to cover a part of the terminal, as the formation position of the organic semiconductor layer, the organic semiconductor layer may be formed so that a part of the terminal is exposed, As illustrated in FIGS. 7A and 7B, the organic semiconductor layer 6 is preferably formed so as to cover the four ends of the terminal 55. This is because adhesion to the interlayer insulating layer and the gate insulating layer can be ensured. Further, since the line width becomes narrow at the boundary between the terminal such as the inspection terminal and the wiring, it is important to prevent oxidation. It is preferable that an organic semiconductor layer is formed in this portion.

In addition to data wiring, wiring connected to external connection terminals such as an FPC connection portion may be formed on the base material, and an organic semiconductor layer is formed so as to cover those wirings. It is preferable.
In addition to the channel region between the source electrode and the drain electrode, the source electrode, the drain electrode, and the data wiring, the organic semiconductor layer has a narrow line width such as a scan wiring and the above-described terminal and wiring boundary. It is preferable that it is formed in a portion that is easily processed. In particular, it is preferable that an organic semiconductor layer is formed on an electrode or wiring having a line width of 20 μm or less and at a boundary with a terminal connected to the electrode or wiring.

  Moreover, it is preferable that the organic-semiconductor layer is not formed in the whole surface of a base material. This is because when the organic semiconductor layer is formed on the entire surface of the base material, a leakage current is generated by the organic semiconductor layer or the electrodes are insulated between the electrodes in the contact hole region or the like.

  The thickness of the organic semiconductor layer only needs to be such that desired semiconductor characteristics can be obtained, and is appropriately selected according to the type of the organic semiconductor material. Specifically, the thickness of the organic semiconductor layer is preferably in the range of 1 nm to 1000 nm, particularly preferably in the range of 5 nm to 300 nm, and more preferably in the range of 20 nm to 100 nm. This is because if the organic semiconductor layer is too thick, a drain current is generated by a sneak current even when the current is turned off in the organic semiconductor element of the present invention, which may result in an increase in the off current. On the other hand, if the thickness of the organic semiconductor layer is too thin, the semiconductor characteristics of the organic semiconductor layer may be insufficient depending on the type of organic semiconductor material.

  As a method for forming the organic semiconductor layer, a method in which the organic semiconductor layer is formed on the entire surface of the base material on which the source electrode, the drain electrode, and the data wiring are formed, and then the organic semiconductor layer is etched using vacuum ultraviolet light is preferable. In addition, since the formation method of an organic-semiconductor layer is described in detail in "B. Manufacturing method of an organic-semiconductor element" mentioned later, description here is abbreviate | omitted.

2. Source electrode and drain electrode The source electrode and the drain electrode in the present invention are formed on a substrate so as to have a desired channel region between the source electrode and the drain electrode, and include a metal material.

  The metal material used for the source electrode and the drain electrode is not particularly limited as long as it has desired conductivity. For example, Ag, Au, Ta, Ti, Al, Zr, Cr, Nb, Hf , Mo, Mo-Ta alloy and the like. Among these, it is preferable that the metal material is easily oxidized. In the present invention, since the oxidation of the source electrode and the drain electrode can be suppressed, it is particularly useful when the source electrode and the drain electrode contain a metal material that is easily oxidized. Examples of such a metal material include Ag, Cu, Al, and alloys thereof. Specific examples of the alloy include Ag, Pd, and Cu alloy called APC.

The thickness of the drain electrode in the contact hole region where the contact hole is formed is equal to the thickness of the drain electrode in the organic semiconductor layer coating region covered with the organic semiconductor layer.
Here, “the thickness of the drain electrode in the contact hole region where the contact hole is formed” means the thickness of the drain electrode in the contact hole region where the contact hole leading to the drain electrode is formed. For example, when the contact hole 12a and the second contact hole 12b are formed as shown in FIG. 5D, the drain electrode 4a in the contact hole region 23 in which the contact hole 12a leading to the drain electrode 4a is formed. Refers to thickness.
Further, “the thickness of the drain electrode in the contact hole region where the contact hole is formed and the thickness of the drain electrode in the organic semiconductor layer covering region covered with the organic semiconductor layer” means that the contact hole in the same element Regarding the average value of the drain electrode in the region and the average value of the drain electrode in the organic semiconductor layer coating region, when the average value of the drain electrode in the organic semiconductor layer coating region is 100%, the organic semiconductor layer coating region The difference between the average value of the drain electrode thickness and the average thickness of the drain electrode in the contact hole region is within ± 30%. Preferably it is within ± 20%, more preferably within ± 10%. Note that the thickness of the drain electrode can be measured by, for example, TEM or SEM.

  The thickness of the source electrode and the drain electrode is not particularly limited as long as it is a thickness that can function as an electrode. Specifically, the thickness is preferably within a range of 0.01 μm to 1 μm, and particularly 0.03 μm to 0.03 μm. It is preferable to be in the range of 5 μm. Further, the thickness of the source electrode and the thickness of the drain electrode may be the same or different.

  The size of the channel region between the source electrode and the drain electrode is appropriately selected according to the use of the organic semiconductor element of the present invention and is not particularly limited. The width of the channel region is not particularly limited as long as an organic semiconductor layer can be formed in the channel region, but is preferably in the range of 1 μm to 100 μm, particularly in the range of 3 μm to 50 μm, and more preferably in the range of 5 μm to It is preferable to be within the range of 10 μm.

  As a method for forming the source electrode and the drain electrode, for example, a metal layer containing the above metal material is formed on the entire surface of the base material by using an evaporation method or the like, and then the above metal material is patterned using a metal mask. The method of vapor-depositing in a shape, the printing method, etc. can be mentioned. A lift-off method can also be used. The method for forming the metal layer can be the same as the general electrode forming method, and specific examples include a sputtering method, a vacuum deposition method, and an ion plating method.

3. Data Wiring The data wiring in the present invention is formed on a base material, connected to the source electrode, and contains a metal material.

Note that the metal material is the same as the metal material used for the source electrode and the drain electrode, and a description thereof is omitted here.
The metal material included in the data wiring may be the same as or different from the metal material included in the source electrode and the drain electrode, but usually the source electrode, the drain electrode and the data wiring are formed at the same time. The metal materials included in the data wiring, the source electrode, and the drain electrode are the same.

  The thickness and formation method of the data wiring can be the same as the thickness and formation method of the source electrode and the drain electrode. In particular, it is preferable to simultaneously form the source electrode, the drain electrode, and the data wiring using the same metal material.

4). Gate Electrode The organic semiconductor element of the present invention has a gate electrode.
The formation position of the gate electrode varies depending on the structure of the organic semiconductor transistor as illustrated in FIGS. 1 and 2 described above.

  Examples of the conductive material used for the gate electrode include metal materials such as Ag, Au, Ta, Ti, Al, Zr, Cr, Nb, Hf, Mo, and Mo—Ta alloy, and metal oxides such as ITO and IZO. Examples thereof include conductive materials such as materials and PEDOT / PSS.

  In an organic semiconductor element having a top gate bottom contact type organic semiconductor transistor, an intermediate electrode 4b connected to the drain electrode 4a may be formed as illustrated in FIG. In this case, the conductive material used for the intermediate electrode can be the same as the conductive material used for the gate electrode.

As a method for forming the gate electrode, for example, after forming a conductive layer on the entire surface of the substrate by a vacuum deposition method or a method of applying and sintering metal nanoparticles, a patterning method or a pattern-like pattern directly on the substrate is used. A method for forming a gate electrode can be given. As a patterning method for the conductive layer, a lithography method is usually used, and among them, a photolithography method is preferably used. On the other hand, as a method for directly forming a patterned gate electrode, a printing method such as a screen printing method or an ink jet method, a mask vapor deposition method, or the like is preferably used.
In addition, when the intermediate electrode is formed, the gate electrode and the intermediate electrode are usually formed collectively.

5. Gate Insulating Layer The organic semiconductor element of the present invention has a gate insulating layer. The gate insulating layer has a function of insulating the source and drain electrodes from the gate electrode.
The formation position of the gate insulating layer varies depending on the structure of the organic semiconductor transistor as illustrated in FIGS. 1 and 2 described above.

The material constituting the gate insulating layer is not particularly limited as long as it is an insulating material having a desired insulating property. For example, acrylic resin, phenol resin, fluorine resin, epoxy resin, cardo type Examples thereof include organic materials such as resins, vinyl resins, imide resins, and novolac resins, and inorganic materials such as SiO ₂ , SiN _x , and Al ₂ O ₃ . One type of insulating material may be used, or two or more types may be used.

As a method for forming the gate insulating layer, for example, when an organic material is used as the insulating material, a coating liquid for forming a gate insulating layer in which the organic material is dissolved in a solvent is prepared, and this is covered with the gate electrode. The method of apply | coating to can be mentioned. Moreover, when using an inorganic material as an insulating material, CVD method etc. can be mentioned, for example.
In the case of forming a gate insulating layer having a contact hole, for example, a photolithography method, a printing method, or the like can be given.

6). External Connection Terminal and Inspection Terminal In the present invention, for example, as shown in FIG. 6, even if an external connection terminal 52 such as an FPC connection portion or an inspection terminal 53 is formed around the display portion 6 on the substrate 2. Good.
In the present invention, the organic semiconductor layer can be formed so as to cover a part of the external connection terminal and the inspection terminal as described above.
The material used for the external connection terminal and the inspection terminal is not particularly limited as long as desired conductivity is obtained. For example, aluminum, silver, copper, or an alloy thereof can be used.
The shape, interval, number, and the like of the external connection terminals and inspection terminals can be the same as those of a general organic semiconductor element, and are set as appropriate.

7). Interlayer Insulating Layer In the present invention, as illustrated in FIGS. 8 and 9, an interlayer insulating layer 10 is formed on the source electrode 3, the drain electrodes 4, 4 a, the organic semiconductor layer 6, the gate electrode 8, and the gate insulating layer 7. It may be formed. The interlayer insulating layer is provided to insulate an external input / output electrode, which will be described later, and a source electrode, a drain electrode, or a gate electrode. In the interlayer insulating layer, a contact hole is formed in a part on the drain electrode in order to connect the external input / output electrode and the drain electrode.
The material and thickness of the interlayer insulating layer can be the same as those used for general organic semiconductor elements.
The method for forming the interlayer insulating layer is not particularly limited as long as it can form an interlayer insulating layer having a contact hole, and examples thereof include a photolithography method and a printing method.

8). Contact hole The contact hole in the present invention is formed so as to penetrate the organic semiconductor layer and reach the drain electrode.

The form of the contact hole differs depending on the structure of the organic semiconductor transistor.
In an organic semiconductor element having a top gate bottom contact type organic semiconductor transistor, a contact hole 12a that penetrates the gate insulating layer 7 and the organic semiconductor layer 6 and a second contact that penetrates the interlayer insulating layer 10 as illustrated in FIG. A hole 12b may be formed. In this case, the contact hole including the contact hole 12 a and the second contact hole 12 b may be formed so as to penetrate the interlayer insulating layer 10 and the organic semiconductor layer 6.
On the other hand, in an organic semiconductor element having a bottom gate bottom contact type organic semiconductor transistor, a contact hole 12 penetrating the interlayer insulating layer 10 and the organic semiconductor layer 6 is formed as illustrated in FIG.

  In the contact hole, the size of the opening of the organic semiconductor layer may be the same as or different from the size of the opening of the interlayer insulating layer or the gate insulating layer. For example, the opening of the organic semiconductor layer 6 may be larger than the opening of the gate insulating layer 7 as shown in FIG. 1, and the opening of the organic semiconductor layer 6 may be an opening of the interlayer insulating layer 10 as shown in FIG. The opening of the organic semiconductor layer 6 may be smaller than the opening of the gate insulating layer 7 as shown in FIG. 8, and the opening of the organic semiconductor layer 6 is an interlayer as shown in FIG. It may be smaller than the opening of the insulating layer 10.

As a method of forming a contact hole in the organic semiconductor layer, an organic semiconductor layer is formed on the entire surface of the base material on which the source electrode, the drain electrode, and the data wiring are formed, and then the organic semiconductor layer is etched using vacuum ultraviolet light. The method is preferred. The method for forming the contact hole in the organic semiconductor layer will be described in detail in “B. Manufacturing method of organic semiconductor element” described later, and thus the description thereof is omitted here.
As a method for forming contact holes in an interlayer insulating layer, a gate insulating layer, or the like, for example, a method of forming contact holes at the same time when forming each layer can be cited. Specific examples include a photolithography method and a printing method.

9. External Input / Output Electrodes In the present invention, as illustrated in FIGS. 8 and 9, external input / output electrodes connected to the drain electrodes 4 and 4a through the contact hole 12 or the second contact hole 12b on the interlayer insulating layer 10 11 may be formed.

The connection mode of the external input / output electrode and the drain electrode differs depending on the structure of the organic semiconductor transistor.
In an organic semiconductor element having a top gate bottom contact type organic semiconductor transistor, an intermediate electrode 4b connected to the drain electrode 4a is formed and penetrates through the gate insulating layer 7 and the organic semiconductor layer 6 as illustrated in FIG. In some cases, a contact hole 12a to be formed and a second contact hole 12b penetrating the interlayer insulating layer 10 are formed. In this case, the drain electrode 4a and the intermediate electrode 4b may be connected through the contact hole 12a, and the intermediate electrode 4b and the external input / output electrode 11 may be connected through the second contact hole 12b.
On the other hand, in an organic semiconductor element having a bottom gate bottom contact type organic semiconductor transistor, the drain electrode 4 and the external input / output electrode 11 are connected through the contact hole 12 as illustrated in FIG.

The external input / output electrodes can be the same as those used for general organic semiconductor elements. For example, when the organic semiconductor element of the present invention is used for driving a display device, a pixel electrode can be used. Moreover, when using the organic-semiconductor element of this invention for a pressure sensor or a temperature sensor, an input electrode can be mentioned.
Conductive materials used for external input / output electrodes include metal materials such as Al, Ti, Cr, and Cu, metal oxide materials such as ITO and IZO, conductive paste materials such as carbon paste and silver paste, and PEDOT / PSS. Examples thereof include conductive polymer materials such as
The external input / output electrode can be formed in the same manner as a general electrode formation method.

10. Base material The base material in this invention supports each layer mentioned above.
The substrate is not particularly limited as long as it has a predetermined self-supporting property, and a substrate having an arbitrary function can be used according to the use of the organic semiconductor element of the present invention. Examples of the base material include a rigid base material such as a glass base material and a flexible base material such as a film made of a plastic resin. Examples of the plastic resin include PET, PEN, PES, PI, PEEK, PC, PPS, and PEI.

  Further, the substrate may be composed of a single layer, or may have a configuration in which a plurality of layers are laminated. Examples of the substrate having a configuration in which a plurality of layers are laminated include those having a configuration in which a barrier layer made of a metal material is laminated on a substrate made of the plastic resin. It has been pointed out that a base material made of a plastic resin has an advantage that the organic semiconductor element of the present invention can be made flexible, but has a drawback that the surface is easily damaged. However, by using a base material on which a barrier layer is laminated, there is an advantage that the above-described drawbacks can be eliminated even when a base material made of a plastic resin is used.

  In general, the thickness of the substrate is preferably 1 mm or less, and more preferably in the range of 50 μm to 700 μm. In addition, when a base material has the structure by which the several layer was laminated | stacked, the said thickness means the sum total of the thickness of each layer.

11. Other Configurations The organic semiconductor element of the present invention is not particularly limited as long as it has the above-described configurations, and other necessary configurations can be added as appropriate.

(1) Light Shielding Layer In the present invention, a light shielding layer may be formed on the organic semiconductor layer. The light shielding layer is provided to prevent light irradiation to the organic semiconductor layer. By forming the light shielding layer, an increase in off current and deterioration of the organic semiconductor layer over time can be suppressed.

  The light-shielding material used for the light-shielding layer is a wavelength that can be absorbed by the organic semiconductor layer and can shield light having a wavelength that causes an increase in off-current or deterioration of the organic semiconductor layer. It is not limited. Examples of such a light-shielding material include a material that absorbs light. Specifically, although depending on the wavelength absorbed by the organic semiconductor layer, metal oxide such as carbon black, titanium black, and black iron oxide is used. And metal sulfides such as bismuth sulfide, black organic pigments such as phthalocyanine black, nigrosine, aniline black and perylene black, and mixtures of chromatic organic pigments such as red, green and blue. In addition, materials that scatter light can also be used. Specifically, inorganic fine particles such as silicon oxide, aluminum oxide, barium sulfate, titanium oxide, and barium titanate, acrylic resins, divinylbenzene resins, and benzoguanamine resins. And styrene resin, melamine resin, acrylic-styrene resin, polycarbonate resin, polyethylene resin, polyvinyl chloride resin and other organic fine particles, or a mixture of two or more of these fine particles. it can.

  In the light shielding layer, the above light shielding material is usually dispersed in a binder resin. Examples of the binder resin include resin materials such as acrylic resin, phenol resin, fluorine resin, epoxy resin, cardo resin, vinyl resin, imide resin, and novolac resin.

  The light shielding layer may be formed as long as the light shielding layer is formed on the organic semiconductor layer. For example, as shown in FIGS. 8 and 9, the source electrode, the drain electrode, the organic semiconductor layer, the gate electrode, and the gate insulating layer are formed. A light shielding layer can be formed thereon.

  Examples of the method for forming the light shielding layer include a method of preparing a light shielding layer forming coating solution prepared by dissolving or dispersing the light shielding material and the binder resin in a solvent, and applying the solution. Moreover, when forming the light shielding layer which has a contact hole, the photolithographic method, the printing method, etc. can be mentioned, for example.

(2) Passivation layer In the present invention, a passivation layer may be formed so as to cover the external input / output electrodes. The passivation layer is provided to prevent the organic semiconductor layer from deteriorating due to the action of moisture and oxygen present in the air. Since the passivation layer is formed, it is possible to prevent the organic semiconductor layer from being deteriorated, so that a high-performance organic semiconductor element with little deterioration with time can be obtained.

  The material constituting the passivation layer is not particularly limited as long as it does not easily transmit moisture and oxygen in the air and can prevent deterioration of the organic semiconductor layer to a desired degree. For example, acrylic resin or fluorine Based resins and the like.

  The thickness of the passivation layer is appropriately adjusted according to the material constituting the passivation layer, but is preferably in the range of, for example, 0.1 μm to 100 μm, and more preferably in the range of 1 μm to 10 μm. Is preferred.

  A method for forming a passivation layer is not particularly limited as long as it can form a passivation layer having a function of preventing deterioration of a desired organic semiconductor layer. When forming a passivation layer for a general organic semiconductor element It can be the same as the method used for.

12 Application As an application of the organic semiconductor element of the present invention, for example, it can be used as a TFT array substrate of a display device using a TFT method. Examples of such a display device include a liquid crystal display device, an electrophoretic display device, and an organic EL display device. The organic semiconductor element can also be used for a temperature sensor, a pressure sensor, or the like.

13. Manufacturing method of organic semiconductor element The manufacturing method of the organic semiconductor element of the present invention is not particularly limited as long as it is a method capable of manufacturing the organic semiconductor element having the above-described configuration. As such a method, for example, the method described in the section of “B. Manufacturing method of organic semiconductor element” described later can be used.

B. Manufacturing method of organic semiconductor element An organic semiconductor element manufacturing method of the present invention includes an organic semiconductor layer forming step of forming an organic semiconductor layer on a substrate on which a source electrode, a drain electrode, and a data wiring including a metal material are formed. The source electrode other than the contact hole region where the contact hole reaching the drain electrode is formed, the electrode region where the drain electrode and the data wiring are formed, and the channel region between the source electrode and the drain electrode A resist layer is formed on the organic semiconductor layer, and the resist layer and the organic semiconductor layer are irradiated with vacuum ultraviolet light to etch the organic semiconductor layer in a portion where the resist layer is not formed, and the resist And an organic semiconductor layer patterning step for removing the layer.

The manufacturing method of the organic semiconductor element of this invention is demonstrated using figures.
4 (a) to 4 (g) and FIGS. 5 (a) to 5 (d) are process diagrams showing an example of the method for producing an organic semiconductor element of the present invention.
First, as shown in FIG. 4A, a base material 2 on which a source electrode 3 and a drain electrode 4a are formed is prepared. Next, as shown in FIG. 4B, an organic semiconductor layer forming step for forming the organic semiconductor layer 6 on the entire surface of the substrate 2 is performed.
Next, as shown in FIG. 4C, the source electrode 3 and the drain electrode 4a other than the channel region 21 between the source electrode 3 and the drain electrode 4a and the contact hole region 23 in which the contact hole is formed are formed. A resist layer 31 is formed on the organic semiconductor layer 6 in the electrode region 22. Next, as shown in FIGS. 4D to 4E, the resist layer 31 and the organic semiconductor layer 6 are irradiated with vacuum ultraviolet light L, so that the organic semiconductor layer 6 in a region where the resist layer 31 is not formed is applied. Etch. Thereafter, as shown in FIG. 4F, the resist layer 31 is removed. Thereby, the organic semiconductor layer 6 having the contact hole 12a is formed so as to cover the source electrode 3 and the drain electrode 4a. In this way, the organic semiconductor layer patterning step is performed.
Next, as shown in FIG. 4G, the gate insulating layer 7 is formed so as to cover the organic semiconductor layer 6 in addition to the contact hole region 23 where the contact hole 12a is formed. Next, a gate electrode 8 is formed on the gate insulating layer 7 as shown in FIG. Further, as shown in FIG. 5A, an intermediate electrode 4b connected to the drain electrode 4a through the contact hole 12a is formed on the gate insulating layer 7.
Next, as shown in FIG. 5B, the light shielding layer 9 is formed so as to cover the gate electrode 8 and the intermediate electrode 4b in addition to the second contact hole region where the second contact hole 12b is formed. Next, as shown in FIG. 5C, an interlayer insulating layer forming step is performed on the light shielding layer 9 to form an interlayer insulating layer 10 in a region other than the second contact hole region where the second contact hole 12b is formed. Subsequently, as shown in FIG. 5D, an external input / output electrode forming step for forming the external input / output electrode 11 connected to the intermediate electrode 4b through the second contact hole 12b on the interlayer insulating layer 10 is performed.

In the present invention, a resist layer is formed on the organic semiconductor layer in the electrode region other than the channel region and the contact hole region, so that the vacuum ultraviolet light L is irradiated as shown in FIGS. When etching the organic semiconductor layer 6, the source electrode 3 and the drain electrode 4 a are covered with the organic semiconductor layer 6 and the resist layer 31 except for the contact hole region 23. Therefore, the source electrode 3 and the drain electrode 4a can be prevented from coming into contact with oxygen. Furthermore, it is possible to prevent the source electrode 3 and the drain electrode 4a from being irradiated with high-energy light in the ultraviolet region, particularly high-energy vacuum ultraviolet light L. Although data wiring is not shown in FIGS. 4A to 4G and FIGS. 5A to 5D, oxygen contact and vacuum are also applied to the data wiring as in the case of the source electrode and the drain electrode. Irradiation with ultraviolet light can be prevented.
Therefore, in the present invention, when the organic semiconductor layer is etched using vacuum ultraviolet light in the organic semiconductor layer patterning step, it is possible to suppress the source electrode, the drain electrode and the data wiring from being oxidized, It is possible to suppress a decrease in electrode performance and disconnection, and to improve electrical connectivity between the source and drain electrodes and the organic semiconductor layer.

According to the present invention, a resist layer is not formed on the organic semiconductor layer in the contact hole region, and the contact hole is formed in the organic semiconductor layer by etching the organic semiconductor layer using vacuum ultraviolet light. It can be suppressed that the drain electrode in the contact hole region is thin. Therefore, contact failure between the drain electrode and the external input / output electrode can be suppressed, and an organic semiconductor element with high electrical reliability can be obtained.
Here, when the contact hole is formed by laser etching after laminating each layer as in the prior art, the drain electrode of the laser irradiated portion is damaged, so that the contact hole region and the region other than the contact hole region are damaged. It is difficult to make the thickness of the drain electrode uniform.
On the other hand, in the present invention, contact holes are formed by etching the organic semiconductor layer using vacuum ultraviolet light. Since vacuum ultraviolet light has lower energy than laser, the drain of the vacuum ultraviolet light irradiated portion Etching to the electrode can be prevented, and a drain electrode having a uniform thickness can be obtained in the contact hole region and a region other than the contact hole region.

  Hereinafter, each process in the manufacturing method of the organic-semiconductor element of this invention is demonstrated.

1. Organic Semiconductor Layer Forming Step The organic semiconductor layer forming step in the present invention is a step of forming an organic semiconductor layer on a base material on which a source electrode, a drain electrode, and a data wiring containing a metal material are formed.

  Since the organic semiconductor material used for the organic semiconductor layer is described in the above-mentioned section “A. Organic semiconductor element”, description thereof is omitted here.

  As a method for forming the organic semiconductor layer, for example, when the organic semiconductor material is soluble in a solvent, the organic semiconductor material is dissolved in the solvent to prepare a coating solution for forming an organic semiconductor layer, which is then used as a base material. The method of apply | coating above is mentioned. Examples of the coating method include spin coating, die coating, roll coating, bar coating, LB, dip coating, spray coating, blade coating, and casting. On the other hand, when the organic semiconductor material is insoluble in a solvent, for example, a dry process such as a vacuum deposition method can be used.

In addition to the source electrode, the drain electrode, and the data wiring, terminals such as an external connection terminal and an inspection terminal may be formed on the base material on which the organic semiconductor layer is formed.
The base material, the source electrode, the drain electrode, the data wiring, the terminal, and the like are described in the above-mentioned section “A. Organic semiconductor element”, and thus the description thereof is omitted here.

2. Organic semiconductor layer patterning step The organic semiconductor layer patterning step in the present invention comprises the source region other than the contact hole region where the contact hole reaching the drain electrode is formed, the electrode region where the drain electrode and the data wiring are formed, And a resist layer is formed on the organic semiconductor layer in the channel region between the source electrode and the drain electrode, and the resist layer is formed by irradiating the resist layer and the organic semiconductor layer with vacuum ultraviolet light. This is a step of etching the organic semiconductor layer at a portion not exposed to remove the resist layer.

  The resist layer shields vacuum ultraviolet light when the organic semiconductor layer is etched using vacuum ultraviolet light. What is necessary is just to determine suitably as the shielding property of the vacuum ultraviolet light of a resist layer according to the wavelength of the irradiated vacuum ultraviolet light. Specifically, the vacuum ultraviolet light transmittance of the resist layer is preferably 10% or less, particularly preferably 3% or less, and more preferably 1% or less.

The resist layer is preferably one that shields oxygen during etching of the organic semiconductor layer using vacuum ultraviolet light. Thereby, the oxidation of the source electrode, the drain electrode and the data wiring can be further suppressed. As for the oxygen shielding property of the resist layer, specifically, the oxygen permeability of the resist layer is preferably 1 cc / m ² / day / atm or less under conditions of a temperature of 23 ° C. and a humidity of 90%. Here, the oxygen permeability is a value measured using an oxygen gas permeability measuring device OX-TRAN 2/20 manufactured by Modern Control Co., Ltd.

  The material used for the resist layer is not particularly limited as long as a resist layer having a predetermined shielding property against the irradiated vacuum ultraviolet light can be obtained. Examples of such materials include PVP, PVA, PMMA, PS, polyethylene oxide, water-based epoxy resin, epoxy resin, acrylic resin, polyimide, cardo resin, and the like. These materials may be used alone or in combination of two or more.

  The resist layer is formed on the organic semiconductor layer in the channel region between the source electrode and the drain electrode and the electrode region in which the source electrode, the drain electrode, and the data wiring other than the contact hole region where the contact hole is formed are formed. Is done. The resist layer is used as a mask for vacuum ultraviolet light when the organic semiconductor layer is etched using vacuum ultraviolet light. Therefore, the pattern shape of the resist layer is the same as the pattern shape of the organic semiconductor layer after etching. The formation position of the organic semiconductor layer after the etching is described in the above section “A, organic semiconductor element”, and thus the description thereof is omitted here.

  The thickness of the resist layer is not particularly limited as long as a predetermined shielding property against vacuum ultraviolet light can be obtained, but is preferably 100 μm or less, and particularly within a range of 0.1 μm to 10 μm. Furthermore, it is preferable to be within the range of 0.3 μm to 1 μm.

  The method for forming the resist layer is not particularly limited as long as the resist layer can be formed on the organic semiconductor layer in a predetermined region. For example, a photolithography method, an inkjet method, a screen printing method, Examples of the printing method include pad printing, flexographic printing, microcontact printing, gravure printing, offset printing, and gravure offset printing.

When patterning the organic semiconductor layer, the portion of the organic semiconductor layer where the resist layer is not formed is removed by irradiating the resist layer and the organic semiconductor layer with vacuum ultraviolet light.
Here, “vacuum ultraviolet light” refers to ultraviolet light having a wavelength in the range of 10 nm to 200 nm. The vacuum ultraviolet light used in the present invention is not particularly limited as long as it has a wavelength capable of removing the organic semiconductor layer within a desired time, and depends on the type of organic semiconductor material constituting the organic semiconductor layer. Thus, vacuum ultraviolet light having an appropriate wavelength may be used. Among these, the wavelength of vacuum ultraviolet light is preferably in the range of 126 nm to 193 nm, and more preferably 172 nm. This is because by using vacuum ultraviolet light in such a wavelength range, the organic semiconductor layer can be patterned in a short time regardless of the type of organic semiconductor material constituting the organic semiconductor layer.

Examples of the light source used for irradiation with vacuum ultraviolet light include an excimer lamp, a low-pressure mercury lamp, and various other light sources.
Further, the amount of irradiation with vacuum ultraviolet light is not particularly limited as long as the organic semiconductor layer can be etched. Depending on the type of organic semiconductor material constituting the organic semiconductor layer, the wavelength of vacuum ultraviolet light, and the like. What is necessary is just to adjust suitably.

The irradiation method of vacuum ultraviolet light is not particularly limited as long as it is a method capable of irradiating the resist layer and the organic semiconductor layer with vacuum ultraviolet light with a uniform irradiation amount. Examples of such an irradiation method include a method of simultaneously irradiating the entire surface of the resist layer and the organic semiconductor layer, and a resist layer while moving at least one of the light source or the substrate on which the resist layer and the organic semiconductor layer are formed. And a method of sequentially irradiating the entire surface of the organic semiconductor layer.
Of these, the latter method is preferably used. The reason is as follows. That is, since vacuum ultraviolet light is non-directional dispersed light, the method of simultaneously irradiating the entire surface of the resist layer and the organic semiconductor layer, for example, when irradiating vacuum ultraviolet light to a large-area resist layer and organic semiconductor layer In addition, there is a possibility that a difference occurs in the irradiation amount of the vacuum ultraviolet light between the central portion and the end portion. However, according to the method of sequentially irradiating the entire surface of the resist layer and the organic semiconductor layer, the vacuum is uniformly applied to the entire surface even when the resist layer and the organic semiconductor layer having a large area are irradiated with vacuum ultraviolet light. This is because it becomes easy to irradiate ultraviolet light.

  Further, among the above-described sequential irradiation methods, it is preferable to use a method in which the substrate on which the resist layer and the organic semiconductor layer are formed is fixed and the light source is moved. This is because according to such a method, it becomes easy to uniformly irradiate vacuum ultraviolet light to a large-area resist layer and organic semiconductor layer.

  There may be one vacuum ultraviolet light source or a plurality of light sources. In addition, when using a plurality of light sources, when using a method of irradiating while moving the light source as a method of irradiating the vacuum ultraviolet light, the plurality of light sources may be moved simultaneously or individually. .

  As a method for removing the resist layer, a general method for removing a resist layer can be used, and both a wet process and a dry process can be applied.

3. Gate electrode formation process In this invention, the gate electrode formation process which forms a gate electrode is performed.
The order of the gate electrode forming step is appropriately selected according to the structure of the organic semiconductor transistor.
In addition, since it described in the above-mentioned item of "A. organic-semiconductor element" about the material of a gate electrode, a formation method, etc., description here is abbreviate | omitted.

4). Gate Insulating Layer Forming Step In the present invention, a gate insulating layer forming step for forming a gate insulating layer is performed.
The order of the gate insulating layer forming step is appropriately selected according to the structure of the organic semiconductor transistor.
In addition, since it described in the above-mentioned item of "A. Organic-semiconductor element" about the material of a gate insulating layer, a formation method, etc., description here is abbreviate | omitted.

5. Interlayer insulating layer forming step In the present invention, an interlayer insulating layer forming step of forming an interlayer insulating layer having a contact hole on the source electrode, drain electrode, organic semiconductor layer, gate electrode and gate insulating layer may be performed. Good.
In addition, since it described in the above-mentioned "A. organic-semiconductor element" about the material, formation method, etc. of an interlayer insulation layer, description here is abbreviate | omitted.

6). External Input / Output Electrode Formation Step In the present invention, an external input / output electrode formation step of forming an external input / output electrode connected to the drain electrode through the contact hole may be performed on the interlayer insulating layer.
Note that the materials and forming methods of the external input / output electrodes are described in the above-mentioned section “A. Organic semiconductor element”, and thus the description thereof is omitted here.

7). Other Steps The method for producing the organic semiconductor element of the present invention is not particularly limited as long as it is a production method having the above-described steps, and necessary steps can be appropriately selected and added.

(1) Light shielding layer formation process In this invention, you may perform the light shielding layer formation process which forms a light shielding layer on an organic-semiconductor layer.
In addition, since it described in the item of the above-mentioned "A. organic-semiconductor element" about the material, formation method, etc. of a light shielding layer, description here is abbreviate | omitted.

(2) Passivation layer formation process In this invention, you may perform the passivation layer formation process which forms a passivation layer so that each layer of an organic-semiconductor element may be covered.
In addition, since it described in the above-mentioned "A. organic-semiconductor element" about the material, formation method, etc. of a passivation layer, description here is abbreviate | omitted.

8). Organic Semiconductor Device An organic semiconductor device manufactured by the method for manufacturing an organic semiconductor device of the present invention has a bottom gate bottom contact type or top gate bottom contact type organic transistor. In addition, since it described in the term of "A. organic semiconductor element" about the organic semiconductor element, description here is abbreviate | omitted.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.

[Example 1]
Silver was sputter-deposited with a thickness of 40 nm on the entire surface of the glass substrate. Next, a positive photoresist was applied onto the sputtered silver film by spin coating to form a resist layer, and the resist layer was patterned through an exposure and development process using a photomask. Next, an etching process was performed to etch the silver sputtered film at a portion where the resist layer was not formed, and then the resist layer was removed. Thereby, a source electrode, a drain electrode and a data wiring were formed.

Next, a xylene solution of an organic semiconductor in which a thiophene polymer is dissolved in xylene at a solid content concentration of 1 wt% is prepared, and applied to the surface of the substrate on which the source electrode, the drain electrode, and the data wiring are formed by spin coating, An organic semiconductor layer having a thickness of 50 nm was formed on the entire surface of the substrate. Next, a positive resist is spin-coated on the organic semiconductor layer to form a resist layer, exposure through a photomask and an alkali development process are performed, the resist layer is patterned, a channel region, a source electrode, a drain electrode, and data A resist layer was formed so as to cover the wiring. At this time, the resist layer is not formed in the contact hole region where the contact hole is formed.
Next, in the atmosphere, vacuum ultraviolet rays having a wavelength of 172 nm and an illuminance of 3 mW / cm ² were irradiated for 60 seconds, the organic semiconductor layer other than the portion covered with the resist layer was removed by etching, and the organic semiconductor layer was patterned. . Thereafter, the resist layer was removed.

  Next, a gate insulating layer is formed by spin-coating an ultraviolet-sensitive acrylic resin on the base material formed up to the organic semiconductor layer, performing an exposure through a photomask and an alkali developing process, Patterning was performed. At this time, patterning was performed so that a contact hole was formed in the gate insulating layer. Subsequently, it was heat-cured in an oven at 150 ° C. to form a gate insulating layer having a thickness of 1 μm.

  Next, Al was sputter-deposited with a thickness of 200 nm on the base material formed up to the gate insulating layer. Subsequently, a positive photoresist was applied onto the Al sputtered film by spin coating to form a resist layer, and the resist layer was patterned through an exposure and development process using a photomask. Etching was performed to etch the Al sputtered film at the portion where the resist layer was not formed, and then the resist layer was removed. Thereby, a gate electrode and an intermediate electrode were formed.

Next, on the substrate formed up to the gate electrode and the intermediate electrode, an ultraviolet photosensitive resin is spin-coated to form a light shielding layer, and exposure through a photomask and an alkali development process are performed to pattern the light shielding layer. went. At this time, patterning was performed so that a contact hole was formed in the light shielding layer. Subsequently, it was heat-cured in an oven at 150 ° C. to form a light-shielding layer having a thickness of 2 μm.
Next, an ultraviolet-sensitive acrylic resin was spin-coated on the light shielding layer to form an interlayer insulating layer, exposure through a photomask and an alkali development process were performed, and the interlayer insulating layer was patterned. At this time, patterning was performed so that contact holes were formed in the interlayer insulating layer. Subsequently, it was heat-cured in an oven at 150 ° C. to form an interlayer insulating layer having a thickness of 4 μm.

  Next, a carbon paste was pattern-printed on the interlayer insulating layer by screen printing and baked in an oven at 120 ° C. to form external input / output electrodes having a film thickness of 5 μm. In this step, the external input / output electrode and the drain electrode of the organic semiconductor transistor were made conductive.

[Comparative Example 1]
It was produced in the same manner as in Example 1 except that the organic semiconductor layer was formed only in the channel region.

[Evaluation]
When the electrical characteristics of the organic semiconductor transistors of Example 1 and Comparative Example 1 were compared, both the On current and the Off current showed the same value, and there was no adverse effect on the characteristics due to the formation of the organic semiconductor layer on the data wiring. It was.
In Comparative Example 1, disconnection due to oxidation of the data wiring was confirmed, but in Example 1, disconnection due to oxidation was not confirmed.
Further, the organic semiconductor transistor of Example 1 was cut with a focused ion beam (FIB), and the cross section was observed with a transmission electron microscope (TEM), so that the thickness of the drain electrode in the contact hole region and the organic semiconductor layer coating region The thickness of the drain electrode was measured. As a result, in any five elements of the array, the difference between the average value of the drain electrode thickness of the organic semiconductor layer covering region and the average value of the drain electrode thickness of the contact hole region in the same element is When the average value of the thickness of the drain electrode in the region was 100%, it was within ± 10%, and it was confirmed that the thicknesses of both were equal.

DESCRIPTION OF SYMBOLS 1 ... Organic-semiconductor element 2 ... Base material 3 ... Source electrode 4, 4a ... Drain electrode 4b ... Intermediate electrode 5 ... Data wiring 6 ... Organic-semiconductor layer 7 ... Gate insulating layer 8 ... Gate electrode 9 ... Light-shielding layer 10 ... Interlayer insulating layer DESCRIPTION OF SYMBOLS 11 ... External input / output electrode 12, 12a ... Contact hole 12b ... Second contact hole 21 ... Channel region 22 ... Electrode region 23 ... Contact hole region 24 ... Organic-semiconductor layer coating region L ... Vacuum ultraviolet light

Claims (3)

A substrate;
A source electrode, a drain electrode and a data wiring formed on the base material and including a metal material;
An organic semiconductor layer formed to cover the source electrode, the drain electrode, and the data wiring;
A contact hole formed so as to penetrate the organic semiconductor layer and reach the drain electrode, and the thickness of the drain electrode in the contact hole region where the contact hole is formed, and the organic semiconductor layer An organic semiconductor element characterized in that the thickness of the drain electrode in the covered organic semiconductor layer region is equal.   The organic semiconductor element according to claim 1, wherein the organic semiconductor layer is formed so as to cover a part of the external connection terminal and the inspection terminal. An organic semiconductor layer forming step of forming an organic semiconductor layer on a base material on which a source electrode, a drain electrode and a data wiring including a metal material are formed;
The source electrode other than the contact hole region where the contact hole reaching the drain electrode is formed, the electrode region where the drain electrode and the data wiring are formed, and the channel region between the source electrode and the drain electrode A resist layer is formed on the organic semiconductor layer, and the resist layer and the organic semiconductor layer are irradiated with vacuum ultraviolet light to etch the organic semiconductor layer in a portion where the resist layer is not formed, and the resist layer An organic semiconductor layer patterning step for removing the organic semiconductor element.

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