JP2006108354A - Field effect transistor and manufacturing method thereof - Google Patents

Abstract

Disclosed is a field effect transistor including a channel forming region having bonds between channel-forming region-constituting fine particles and organic semiconductor molecules arranged with substantially regularity.
A field effect transistor includes a source / drain electrode, a channel formation region, a gate insulating layer, and a gate electrode, and at least a portion of a support located between the source / drain electrodes and a channel. A base layer 30 is formed between the base layer 30 and the formation region 15. The base layer 30 is composed of base layer-constituting particles 31 made of an electrically insulating material and arranged with a regularity. The channel formation region 15 is a conductor or a semiconductor. Channel forming region constituting fine particles 21 and organic semiconductor molecules 22 bonded to the channel forming region constituting fine particles 21, and the channel forming region constitution based on the fine particle arrangement state of the underlayer 30. The fine particles 21 are arranged with substantially regularity.
[Selection] Figure 1

Description

  The present invention relates to a field effect transistor and a manufacturing method thereof.

Field effect transistors (FETs) including thin film transistors (TFTs) currently used in many electronic devices are, for example, channel formation regions and source / drains formed in a silicon semiconductor substrate or silicon semiconductor layer. A gate insulating layer made of SiO ₂ formed on the region, the surface of the silicon semiconductor substrate or the surface of the silicon semiconductor layer, and a gate electrode provided facing the channel formation region via the gate insulating layer. Alternatively, it includes a gate electrode formed on the support, a gate electrode and a gate insulating layer formed on the support, and a channel formation region and source / drain electrodes formed on the gate insulating layer. . For manufacturing field effect transistors having these structures, very expensive semiconductor manufacturing apparatuses are used, and reduction of manufacturing costs is strongly demanded.

  Therefore, in recent years, attention has been focused on the research and development of FETs using organic semiconductor materials that can be manufactured based on methods that do not use vacuum techniques exemplified by spin coating, printing, and spraying.

  By the way, since it is required to be incorporated into many electronic devices including a display device, the FET is required to operate at high speed. For example, there is a need for an FET that can convert a video signal into necessary data at any time and can perform an on / off switching operation at high speed.

However, when an organic semiconductor material is used, for example, the mobility, which is a characteristic index of a TFT, is only 10 ^{−3 to 1} cm ² / Vs as a typical value (for example, CD Dimitrakopoulos, et al ., Adv. Mater. (2002), 14, 99). This value is lower than several cm ² / Vs, which is the mobility of amorphous silicon, and approximately 100 cm ² / Vs, which is the mobility of polysilicon, and is 1 to 3 cm ² / Vs required for TFTs for display devices. Not reached. Therefore, in the FET using an organic semiconductor material, improvement of mobility is a big problem.

  Mobility in an FET using an organic semiconductor material is determined by charge transfer within a molecule and charge transfer between molecules. Intramolecular charge transfer is made possible by overlapping atomic bonds in adjacent multiple bonds across a single bond and delocalizing electrons to form a conjugated system. The movement of charge between molecules is performed by intermolecular bonding, conduction due to overlapping of molecular orbitals by van der Waals forces, or hopping conduction through trap levels between molecules.

In this case, if the intramolecular mobility is μ _intra , the intermolecular mobility is μ _inter , and the intermolecular hopping mobility is μ _hop , the following relationship is established. In an organic semiconductor material, the charge mobility is low because slow intermolecular charge transfer limits the overall mobility.

μ _intra ≫μ _inter > μ _hop

International Publication WO2004 / 006337A1 C. D. Dimitrakopoulos, et al., Adv. Mater. (2002), 14, 99

  Therefore, various studies have been made to improve the mobility in FETs using organic semiconductor materials.

  For example, in the semiconductor device disclosed in International Publication WO2004 / 006337A1, a conductive path is formed by fine particles made of a conductor or a semiconductor and organic semiconductor molecules bonded to the fine particles, and the conductivity of the conductive path is controlled by an electric field. Is done. By adopting such a structure, charge movement in the conductive path occurs predominantly in the axial direction of the molecule along the main chain of the organic semiconductor molecule, and the mobility in the axial direction of the molecule, for example, non-locality It is possible to make maximum use of the high intramolecular mobility due to the activated p electrons. As a result, an unprecedented high mobility comparable to that of a monolayer transistor can be realized.

  By the way, in the semiconductor device disclosed in this international publication WO2004 / 006337A1, the conductive path constituting the channel formation region can be formed by a simple and low-cost process using a solution. In order to form the source / drain electrode, the gate electrode, and the gate insulating layer, a high temperature process or a high vacuum process is required. Therefore, it is difficult to achieve simplification and cost reduction of the manufacturing process of the entire semiconductor device.

  In addition, since no particular regularity is given to the arrangement of the fine particles constituting the conductive path, the distance between the fine particles varies, and there are fine particles in which the fine particles and the fine particles are not bonded by the organic semiconductor molecules. There is a risk that the number of roads may not be sufficiently secured.

  Therefore, a first object of the present invention is to provide a channel forming region constituting fine particle in a channel forming region having a conductive path constituted by channel forming region constituting fine particles and organic semiconductor molecules bonded to the channel forming region constituting fine particles. It is an object of the present invention to provide a field effect transistor that can be arranged with substantially regularity and a manufacturing method thereof. A second object of the present invention is to provide a field effect transistor that does not require a high-temperature process or a high-vacuum process in the formation of any or all of the source / drain electrode, the gate electrode, and the gate insulating layer, and its manufacture. It is to provide a method.

The field effect transistor according to the first aspect of the present invention for achieving the first object is as follows.
(A) source / drain electrodes formed on a support;
(B) a channel formation region formed on a portion of the support located between the source / drain electrodes and the source / drain electrodes;
(C) a gate insulating layer formed on the entire surface, and
(D) a gate electrode formed on the gate insulating layer so as to face the channel formation region;
A field effect transistor comprising:
An underlayer is formed at least between the portion of the support located between the source / drain electrode and the source / drain electrode and the channel formation region,
The underlayer is composed of underlayer-constituting particles made of an electrically insulating material arranged with substantially regularity.
The channel forming region has a channel formed by a conductor or a semiconductor, and has a conductive path formed by organic semiconductor molecules bonded to the channel forming region forming particle.
The channel forming region constituting fine particles are arranged with substantially regularity based on the fine particle arrangement state of the underlayer.

The field effect transistor according to the second aspect of the present invention for achieving the first and second objects is as follows:
(A) a gate electrode formed on a support;
(B) a gate insulating layer formed on the gate electrode and on the support;
(C) a source / drain electrode formed on the gate insulating layer, and
(D) a channel formation region formed on the portion of the gate insulating layer located between the source / drain electrode and the source / drain electrode, facing the gate electrode;
A field effect transistor comprising:
The gate insulating layer includes a fine particle layer in which the fine particles constituting the gate insulating layer made of an electrically insulating material are arranged with substantially regularity,
The channel forming region has a channel formed by a conductor or a semiconductor, and has a conductive path formed by organic semiconductor molecules bonded to the channel forming region forming particle.
Based on the fine particle arrangement state of the fine particle layer, the channel forming region constituting fine particles are arranged with substantially regularity.

The field effect transistor according to the third aspect of the present invention for achieving the second object described above,
(A) source / drain electrodes formed on a support;
(B) a channel formation region formed on a portion of the support located between the source / drain electrodes and the source / drain electrodes;
(C) a gate insulating layer formed on the source / drain electrode and the channel formation region; and
(D) a gate electrode formed on the gate insulating layer so as to face the channel formation region;
A field effect transistor comprising:
The channel forming region has a conductive path constituted by channel forming region constituting fine particles made of a conductor and organic semiconductor molecules bonded to the channel forming region constituting fine particles,
The source / drain electrodes are characterized by being composed of a layer in which channel forming region constituting fine particles are melted.

The field effect transistor according to the fourth aspect of the present invention for achieving the second object described above,
(A) a gate electrode formed on a support;
(B) a gate insulating layer formed on the gate electrode and on the support;
(C) a source / drain electrode formed on the gate insulating layer, and
(D) a channel formation region formed on the portion of the gate insulating layer located between the source / drain electrode and the source / drain electrode, facing the gate electrode;
A field effect transistor comprising:
The channel forming region has a conductive path constituted by channel forming region constituting fine particles made of a conductor and organic semiconductor molecules bonded to the channel forming region constituting fine particles,
The source / drain electrodes are characterized by being composed of a layer in which channel forming region constituting fine particles are melted.

The field effect transistor according to the fifth aspect of the present invention for achieving the second object described above,
A field effect transistor comprising a gate electrode, a gate insulating layer, a source / drain electrode, and a channel formation region,
The channel forming region has a channel formed by a conductor or a semiconductor, and has a conductive path formed by organic semiconductor molecules bonded to the channel forming region forming particle.
Any or all of the source / drain electrode, the gate electrode, and the gate insulating layer are made of fine particles.

A method for manufacturing a field effect transistor according to the first aspect of the present invention for achieving the first object is as follows.
(A) source / drain electrodes formed on a support;
(B) a channel formation region formed on a portion of the support located between the source / drain electrodes and the source / drain electrodes;
(C) a gate insulating layer formed on the entire surface, and
(D) a gate electrode formed on the gate insulating layer so as to face the channel formation region;
A method of manufacturing a field effect transistor comprising:
Forming a base layer in which base layer-constituting particles made of an electrically insulating material are arranged with substantially regularity on at least a portion of the support located between the source / drain electrode and the source / drain electrode; ,
Forming a channel forming region having a conductive path constituted by channel-forming region-constituting particles made of a conductor or semiconductor and organic semiconductor molecules bonded to the channel-forming region-constituting fine particles on the underlayer;
Including
The channel forming region constituting fine particles are arranged with substantially regularity based on the fine particle arrangement state of the underlayer.

A method for manufacturing a field effect transistor according to the second aspect of the present invention for achieving the first and second objects described above,
(A) a gate electrode formed on a support;
(B) a gate insulating layer formed on the gate electrode and on the support;
(C) a source / drain electrode formed on the gate insulating layer, and
(D) a channel formation region formed on the portion of the gate insulating layer located between the source / drain electrode and the source / drain electrode, facing the gate electrode;
A method of manufacturing a field effect transistor comprising:
Forming a gate insulating layer comprising a fine particle layer in which fine particles constituting a gate insulating layer made of an electrically insulating material are arranged with substantially regularity on a gate electrode and a support;
Forming a channel forming region having a conductive path constituted by channel forming region constituting fine particles made of a conductor or a semiconductor and organic semiconductor molecules combined with the channel forming region constituting fine particles on the fine particle layer;
Including
The channel-forming region constituting fine particles are arranged with substantially regularity based on the fine particle arrangement state of the fine particle layer.

A method for manufacturing a field effect transistor according to the third aspect of the present invention to achieve the second object described above,
(A) source / drain electrodes formed on a support;
(B) a channel formation region formed on a portion of the support located between the source / drain electrodes and the source / drain electrodes;
(C) a gate insulating layer formed on the source / drain electrode and the channel formation region; and
(D) a gate electrode formed on the gate insulating layer so as to face the channel formation region;
A method of manufacturing a field effect transistor comprising:
After forming a layer made up of channel-forming region-constituting particles made of a conductor on a support,
The source / drain electrode is formed by melting the layer composed of the channel forming region constituting fine particles in the region where the source / drain electrode is to be formed, and the organic semiconductor is formed in the layer constituted of the channel forming region constituting fine particles. Forming a channel forming region having a conductive path constituted by channel forming region constituting fine particles and organic semiconductor molecules bonded to the channel forming region constituting fine particles by contacting molecules.
Including a process.

A method for manufacturing a field effect transistor according to the fourth aspect of the present invention for achieving the second object described above,
(A) a gate electrode formed on a support;
(B) a gate insulating layer formed on the gate electrode and on the support;
(C) a source / drain electrode formed on the gate insulating layer, and
(D) a channel formation region formed on the portion of the gate insulating layer located between the source / drain electrode and the source / drain electrode, facing the gate electrode;
A method of manufacturing a field effect transistor comprising:
After forming a layer composed of channel forming region constituting fine particles made of a conductor on the gate insulating layer,
The source / drain electrode is formed by melting the layer composed of the channel forming region constituting fine particles in the region where the source / drain electrode is to be formed, and the organic semiconductor is formed in the layer constituted of the channel forming region constituting fine particles. Forming a channel forming region having a conductive path constituted by channel forming region constituting fine particles and organic semiconductor molecules bonded to the channel forming region constituting fine particles by contacting molecules.
Including a process.

A method for manufacturing a field effect transistor according to the fifth aspect of the present invention for achieving the second object described above,
An organic semiconductor comprising a gate electrode, a gate insulating layer, a source / drain electrode, and a channel formation region, wherein the channel formation region is composed of channel formation region constituting fine particles made of a conductor or a semiconductor, and the channel formation region constituting fine particles. A method of manufacturing a field effect transistor having a conductive path composed of molecules,
Any or all of the source / drain electrode, the gate electrode, and the gate insulating layer are formed from fine particles.

In the method of manufacturing the field effect transistor according to the third aspect or the fourth aspect of the present invention, the layer formed of the channel forming region constituting fine particles in the region where the source / drain electrode is to be formed is melted. Thus, the source / drain electrodes are formed, and the organic semiconductor molecules are brought into contact with the layer composed of the channel-forming region-constituting fine particles, thereby combining the channel-forming region-constituting fine particles and the channel-forming region-constituting fine particles. Forming a channel formation region having a conductive path composed of organic semiconductor molecules,
(1) A source / drain electrode is formed by melting a layer composed of channel-forming region-constituting particles in a region where a source / drain electrode is to be formed. By bringing the organic semiconductor molecules into contact with each other, a channel forming region having a channel formed by the channel forming region constituting fine particles and an organic semiconductor molecule bonded to the channel forming region constituting fine particles may be formed.
(2) By bringing an organic semiconductor molecule into contact with a layer composed of channel-forming region-constituting fine particles, a conductive path composed of the channel-forming region-constituting fine particles and organic semiconductor molecules combined with the channel-forming region-constituting fine particles Forming a channel forming region and a channel forming region extending portion, and then melting a layer (channel forming region extending portion) composed of channel forming region constituting fine particles in a region where a source / drain electrode is to be formed. Source / drain electrodes may be formed, and this procedure (2) is preferred to procedure (1).

  In the field effect transistors according to the first to fifth aspects of the present invention (hereinafter, these may be collectively referred to simply as the field effect transistors of the present invention), organic semiconductor molecules It is preferable that the functional group possessed at the end is chemically bonded to the channel-forming region constituting fine particles. In this case, the organic semiconductor molecule and the channel-forming region-constituting fine particles are chemically (alternatively) bonded to each other by the functional groups of the organic semiconductor molecule at both ends, so that a network-like conductive path is constructed. More preferably, the conductive path is preferably constituted by a single layer of a combination of channel-forming region-constituting fine particles and organic semiconductor molecules. Alternatively, in this case, the organic semiconductor molecule and the channel-forming region-constituting fine particles are three-dimensionally chemically (alternately) bonded by the functional groups of the organic semiconductor molecule at both ends, thereby constructing a network-like conductive path. Furthermore, it is preferable that the conductive path is constituted by a laminated structure of a combined body of channel-forming region constituting fine particles and organic semiconductor molecules.

  On the other hand, the method for producing field effect transistors according to the first to fifth aspects of the present invention (hereinafter, these may be collectively referred to simply as the method for producing the field effect transistor of the present invention). In this case, it is preferable that the organic semiconductor molecule is chemically bonded to the channel-forming region-constituting fine particles by the functional group at the end. And in this case, it is preferable to construct a network-like conductive path by chemically (alternatively) bonding the organic semiconductor molecule and the channel-forming region constituting fine particles by the functional group that the organic semiconductor molecule has at both ends, Furthermore, it is preferable that the conductive path is constituted by a single layer of a combination of fine particles forming the channel forming region and organic semiconductor molecules. Alternatively, in this case, a network-like conductive path is constructed by three-dimensionally (alternatively) bonding organic semiconductor molecules and channel-forming region-constituting particles by functional groups possessed by the organic semiconductor molecules at both ends. Further, it is preferable that the conductive path is constituted by a laminated structure of a combined body of channel forming region constituting fine particles and organic semiconductor molecules.

  The field effect transistor according to the first aspect to the fifth aspect of the present invention or the method for producing the field effect transistor according to the first aspect to the fifth aspect of the present invention (hereinafter collectively referred to simply as In some cases, the present invention may be referred to as the present invention, and by constructing such a kind of network-like conductive path, the charge transfer in the conductive path causes the molecular axial direction along the main chain of the organic semiconductor molecule. As a result, the molecular mobility in the axial direction, for example, high mobility due to delocalized π-electrons can be utilized to the maximum, which is comparable to a monolayer transistor. Unprecedented high mobility can be realized.

In the present invention, the fine particles forming the channel forming region are gold (Au), silver (Ag), platinum (Pt), copper (Cu), aluminum (Al), palladium (Pd), chromium (Cr), nickel as conductors. (Ni), iron (Fe), or an alloy composed of these metals, or cadmium sulfide (CdS), cadmium selenide (CdSe), or cadmium telluride (CdTe) as a semiconductor. ), Gallium arsenide (GaAs), titanium oxide (TiO ₂ ), or silicon (Si). The channel forming region constituting fine particles as a conductor refers to channel forming region constituting fine particles made of a material having a volume resistivity of the order of 10 ⁻⁴ Ω · m (10 ⁻⁶ Ω · cm) or less. Further, the channel forming region constituting fine particles as a semiconductor is a material having a volume resistivity of the order of 10 ⁻⁴ Ω · m (10 ⁻⁶ Ω · cm) to 10 ¹² Ω · m (10 ¹⁰ Ω · cm). The channel-forming region constituting fine particles consisting of

Here, it is preferable that σ / r _AVE ≦ 0.5 is satisfied, where r _AVE is the average particle diameter of the fine particles forming the channel forming region and σ is the standard deviation of the particle diameter of the fine particles forming the channel forming region. The r _AVE range is not limited, but 5.0 × 10 ⁻¹⁰ m ≦ r _AVE ≦ 1.0 × 10 ⁻⁶ m, preferably 5.0 × 10 ⁻¹⁰ m ≦ r _AVE ≦ It is desirable that it is 1.0 × 10 ⁻⁸ m. The shape of the channel-forming region-constituting fine particles can include a sphere, but the present invention is not limited to this, and for example, in addition to a sphere, a triangle, a tetrahedron, a cube, a cuboid, a cone, a cylinder, and the like can be given. . Note that the average particle diameter of the channel forming region constituting fine particles when the shape of the channel forming region constituting fine particles is other than spherical is assumed to be a sphere having the same volume as the measured volume of the non-spherical channel forming region constituting fine particles. The average value of the diameters of the spheres may be the average particle diameter of the channel forming region constituting fine particles.

From the viewpoint of preventing aggregation of the channel-forming region-constituting fine particles, the surface of the channel-forming region-constituting fine particles before being bonded to the organic semiconductor molecules is covered with a protective film made of chain-like insulating organic molecules. preferable. The molecules constituting the protective film are bonded to the channel-forming region-constituting fine particles, but the binding strength of the molecules forming the channel-forming region is covered by the protective film (actually, it is covered by the protective film. It has a great influence on the final diameter distribution of the aggregates (clusters) when producing the aggregates or clusters of the channel-forming region constituting particles. It is preferable that one end of the insulating organic molecule constituting the protective film has a functional group that chemically reacts (bonds) with the fine particles forming the channel formation region. For example, a thiol group (—SH) can be given as a functional group, and an alkanethiol [eg, dodecanethiol (C ₁₂ H ₂₅ SH)] can be given as one of molecules having this thiol group at the terminal. It is considered that when a thiol group of dodecanethiol is bonded to fine particles forming a channel forming region such as gold, a hydrogen atom is detached and becomes C ₁₂ H ₂₅ S—Au. Alternatively, as an insulating organic molecule constituting the protective film, an alkylamine molecule [for example, dodecylamine (C ₁₂ H ₂₅ NH ₂ )] can be exemplified.

  Here, when the channel forming region constituting fine particles and the organic semiconductor molecule are brought into contact with each other, the organic semiconductor molecules are replaced with the organic molecules constituting the protective film. As a result, the channel forming region constituting fine particles and the organic semiconductor molecules constituting the channel forming region are replaced. The chemical conjugate is formed.

  In the method for producing a field effect transistor of the present invention, the step of bringing the channel forming region constituting fine particles and the organic semiconductor molecule into contact with each other may be performed at least once in order to bond the channel forming region constituting fine particles and the organic semiconductor molecules. . Further, the contact between the channel forming region constituting fine particles and the organic semiconductor molecule can be specifically achieved by, for example, immersing the channel forming region constituting fine particles in a solution of the organic semiconductor molecule.

In the present invention, the organic semiconductor molecule is an organic semiconductor molecule having a conjugated bond, and at both ends of the molecule, a thiol group (—SH), an amino group (—NH ₂ ), an isocyano group (—NC), a cyano group ( -CN), Chioasetokishiru group (-SCOCH _3), or preferably has a carboxyl group (-COOH). A thiol group, an amino group, an isocyano group, a cyano group, and a thioacetoxyl group are functional groups that bind to a channel forming region constituent fine particle as a conductor such as Au, and a carboxyl group is a channel forming region constituent fine particle as a semiconductor. Is a functional group that binds to The functional groups located at both ends of the molecule may be different, and it is more preferable that the functional groups at both ends are close to the channel forming region constituting fine particles.

  Specifically, as the organic semiconductor molecule, for example, 4,4′-biphenyldithiol (BPDT) of the structural formula (1), 4,4′-diisocyanobiphenyl of the structural formula (2), structural formula (3) 4,4′-diisocyano-p-terphenyl and 2,5-bis (5′-thioacetoxyl-2′-thiophenyl) thiophene of the structural formula (4), 4,4 ′ of the structural formula (5) -Diisocyanophenyl, benzidine (biphenyl-4,4'-diamine) of structural formula (6), TCNQ (tetracyanoquinodimethane) of structural formula (7), biphenyl-4,4 of structural formula (8) '-Dicarboxylic acid, 1,4-di (4-thiophenylacetylinyl) -2-ethylbenzene of structural formula (9), 1,4-di (4-isocyanophenylacetylinyl of structural formula (10) ) -2-Ethylbenzene It can be exemplified Bovine Serum Albumin, Horse Radish Peroxidase, the Antibody-Antigen. These are all π-conjugated molecules, and preferably have functional groups that chemically bond with the channel-forming region-constituting fine particles in at least two places.

Structural formula (1): 4,4′-biphenyldithiol

Structural formula (2): 4,4′-diisocyanobiphenyl

Structural formula (3): 4,4′-diisocyano-p-terphenyl

Structural formula (4): 2,5-bis (5′-thioacetoxyl-2′-thiophenyl) thiophene

Structural formula (5): 4,4′-diisocyanophenyl

Structural formula (6): benzidine (biphenyl-4,4′-diamine)

Structural formula (7): TCNQ (tetracyanoquinodimethane)

Structural formula (8): Biphenyl-4,4′-dicarboxylic acid

Structural formula (9): 1,4-di (4-thiophenylacetylinyl) -2-ethylbenzene

Structural formula (10): 1,4-di (4-isocyanophenylacetylinyl) -2-ethylbenzene

  A dendrimer represented by the structural formula (11) can also be used as the organic semiconductor molecule.

Structural formula (11): Dendrimer

In the method of manufacturing the field effect transistor according to the fifth aspect of the present invention or the field effect transistor according to the fifth aspect of the present invention,
(1) Form in which source / drain electrode is made of fine particles (2) Form in which gate electrode is made of fine particles (3) Form in which gate insulating layer is made of fine particles (4) Source / drain electrode is made of fine particles, and gate electrode is a source (5) The source / drain electrode is composed of fine particles, and the gate insulating layer is composed of fine particles constituting the source / drain electrodes and different types of fine particles (6) ) Form in which the gate electrode is composed of fine particles, and the gate insulating layer is composed of fine particles constituting the gate electrode and other kinds of fine particles. (7) The source / drain electrodes are composed of fine particles, and the gate electrode is composed of fine particles constituting the source / drain electrode. And the gate insulating layer constitutes the source / drain electrode and the gate electrode. It can be mentioned seven forms of embodiment consisting of particles with another type of particles.

  Here, any or all of the source / drain electrode, the gate electrode, and the gate insulating layer are “consisting of fine particles” means that any or all of the source / drain electrode, the gate electrode, and the gate insulating layer are included. In addition to the case of being composed of an aggregate of fine particles, the case of being composed of fine particles as a raw material (for example, comprising fine particles and a binder) is also included. In addition, any or all of the source / drain electrode, the gate electrode, and the gate insulating layer are “formed from fine particles”, which means that any or all of the source / drain electrode, the gate electrode, and the gate insulating layer are formed. It means that it is formed from an appropriate material using fine particles as a raw material (for example, formed based on a material composed of fine particles and a binder, a material composed of fine particles and a dispersion medium, etc.).

  In the field effect transistor according to the first aspect of the present invention or the method of manufacturing the same, any or all of the source / drain electrode, the gate electrode, and the gate insulating layer are made of fine particles. Alternatively, all can be formed from fine particles.

  In the field effect transistor or the method for manufacturing the same according to the second aspect of the present invention, either or all of the source / drain electrode and the gate electrode are formed of fine particles, All can also be formed from fine particles.

  Furthermore, in the field effect transistor according to the second aspect of the present invention or the method for manufacturing the same, the gate insulating layer can have a single-layer structure of a fine particle layer, or two layers of a fine particle layer and a film-like layer. A layer structure can also be used.

  In the field effect transistor according to the third aspect or the fourth aspect of the present invention or the manufacturing method thereof, either or all of the gate electrode and the gate insulating layer are formed of fine particles. Any or all of them can be formed from fine particles. Furthermore, in the field effect transistor according to the third aspect of the present invention or the method for manufacturing the same, the underlayer is formed in the same manner as the field effect transistor according to the first aspect of the present invention or the method for manufacturing the same. May be. Further, in the field effect transistor according to the fourth aspect of the present invention or the method for manufacturing the same, the fine particle layer is provided as in the field effect transistor according to the second aspect of the present invention or the method for manufacturing the same. It can also be a gate insulating layer.

  In the field effect transistor or the manufacturing method thereof according to the first to fourth aspects of the present invention, electrodeposition, spin coating, casting, advection integration ( AS Dimitrov et al., Langmuir, 10, 432 (1994)), a method similar to the LB (Langmuir-Blodgett) method [underlying layer comprising fine particles and gate insulation having a hydrophobic surface on a hydrophilic solvent (eg water) The layer-constituting fine particles are floated in a single layer so as to have a two-dimensional regular arrangement, or conversely, the base layer constituting fine particles having a hydrophilic surface on the hydrophobic solvent or the gate insulating layer constituting fine particles are divided into two A method of floating like a dimensionally ordered array and transferring it like the LB method (see V. Santhanam, et al., Langmuir, 2003, 19, 7881)].

  Here, the base layer constituting fine particles are arranged with substantially regularity, or the gate insulating layer constituting fine particles are arranged with substantially regularity. This means that the base layer constituting fine particles and the gate insulating layer constituting fine particles are equilateral triangles. It means that they are densely arranged so as to be located at the vertices, or densely arranged so as to be located at the vertices of the square. Since not all of the underlying layer constituent fine particles and the gate insulating layer constituent fine particles are arranged with regularity, it is needless to say that there may be some depletion, lattice defects, etc. It is expressed as "almost" ordered.

  In the field effect transistor according to the first to fourth aspects of the present invention or the method of manufacturing the same, in order to arrange the channel-forming region-constituting particles on the underlayer or the gate insulating layer, the channel-forming region configuration After a thin film made of a solution containing fine particles is formed on the base layer or the gate insulating layer, the solvent contained in the solution may be evaporated. Examples of the method for forming a thin film made of a solution containing channel forming region constituting fine particles include an immersion method, a casting method, and a spin coating method. This also makes it possible to obtain a layer composed of channel-forming region-constituting particles made of a conductor in the field-effect transistor according to the third aspect or the fourth aspect of the present invention or the manufacturing method thereof.

  The channel forming region constituent particles are arranged with substantially regularity. When the base layer constituent particles and the gate insulating layer constituent particles are densely arranged so as to be located at the vertices of the equilateral triangle, the center of the equilateral triangle is arranged. It means that the channel forming region constituting fine particles are located on the normal line passing through. In this case, the channel forming region constituting fine particles are located at the apex of the regular triangle formed by the channel forming region constituting fine particles, or are located at the vertex of the regular hexagon formed by the channel forming region constituting fine particles. . On the other hand, when the base layer constituent fine particles and the gate insulating layer constituent fine particles are densely arranged so as to be located at the apex of the square, it means that the channel forming region constituent fine particles are located on the normal passing through the center of the square. . In this case, the channel forming region constituent fine particles are located at the apexes of the square formed by the channel forming region constituent fine particles. Since not all of the channel-forming region-constituting particles are regularly arranged, that is, there may be some depletion, lattice defects, etc. It is expressed that it is arranged.

  In these cases, the distance between the channel forming region constituent fine particles and the channel forming region constituent fine particles is such that the channel forming region constituent fine particles and the channel forming region constituent fine particles are appropriately connected by the organic semiconductor molecules. It is desirable. That is, such a state can be achieved by appropriately selecting the particle diameters of the channel-forming region constituting fine particles, the underlayer constituting fine particles and the gate insulating layer constituting fine particles, and the organic semiconductor molecules. In other words, it is most preferable that the distance between the surfaces of the adjacent channel forming region constituting fine particles is substantially the same as the length in the major axis direction of the organic semiconductor molecule to be used. Since organic semiconductor molecules always exist between the channel forming region constituent fine particles, the channel forming region constituent fine particles are not in contact with each other. The layer in which the channel forming region constituting fine particles are regularly arranged two-dimensionally may be a single layer or a multilayer.

In the present invention, as the fine particles constituting the gate insulating layer, or as the ground layer constituting fine particles constituting the ground layer in the field effect transistor according to the first aspect of the present invention or the manufacturing method thereof, or the present invention. As the fine particles constituting the gate insulating layer of the fine particle layer constituting the gate insulating layer in the field effect transistor according to the second aspect of the present invention or the manufacturing method thereof, silicon oxide (SiO _x ), silicon nitride (SiN _Y ), aluminum oxide (Al ₂ O ₃ ) and other inorganic insulating materials such as highly insulating metal oxides or highly insulating metal nitrides, as well as polymethyl methacrylate (PMMA), polyvinyl phenol (PVP), polyvinyl alcohol (PVA), polyimide , Polycarbonate (PC), polyethylene terephthalate (PE ), Can be exemplified fine particles of organic insulating materials exemplified by polystyrene (organic polymers) may also be used a combination thereof. The shape of these fine particles is preferably spherical.

Alternatively, in the present invention, a highly insulating metal such as silicon oxide (SiO _x ), silicon nitride (SiN _y ) or aluminum oxide (Al ₂ O ₃ ) is used as a material constituting the gate insulating layer having a film-like form. Not only inorganic insulating materials such as oxides or highly insulating metal nitrides, but also polymethyl methacrylate (PMMA), polyvinyl phenol (PVP), polyvinyl alcohol (PVA), polyimide, polycarbonate (PC), polyethylene terephthalate (PET), Silanol derivatives (silane coupling agents) such as N-2 (aminoethyl) 3-aminopropyltrimethoxysilane (AEAPTMS), 3-mercaptopropyltrimethoxysilane (MPTMS), octadecyltrichlorosilane (OTS), octadecanethiol, dodecyl It can be exemplified organic insulating material exemplified by straight-chain hydrocarbons (organic polymer) having a functional group capable of bonding to the gate electrode or the like to one end of such Soshianeito, can also be used a combination thereof. Furthermore, BPSG, PSG, BSG, AsSG, PbSG, silicon oxynitride (SiON), SOG (spin-on-glass), low dielectric constant SiO ₂ materials (eg, polyaryl ethers, cycloperfluorocarbon polymers and benzocyclobutene, cyclic Examples thereof include silicon oxide materials such as fluororesin, polytetrafluoroethylene, fluorinated aryl ether, fluorinated polyimide, amorphous carbon, and organic SOG).

  In the present invention, when the gate electrode and the source / drain electrode are composed of fine particles, platinum (Pt), gold (Au), palladium (Pd), and chromium (Cr) are used as materials constituting the gate electrode and the source / drain electrode. Nickel (Ni), Aluminum (Al), Silver (Ag), Tantalum (Ta), Tungsten (W), Copper (Cu), Titanium (Ti), Indium (In), Tin (Sn), Iron (Fe) , Conductive particles made of a metal such as cobalt (Co) and molybdenum (Mo), and conductive particles of an alloy containing these metals.

  On the other hand, when the gate electrode and the source / drain electrode are not composed of fine particles (that is, in the case of taking a film form), platinum (Pt), gold (Au), Palladium (Pd), chromium (Cr), nickel (Ni), aluminum (Al), silver (Ag), tantalum (Ta), tungsten (W), copper (Cu), titanium (Ti), indium (In), Examples thereof include metals such as tin (Sn), iron (Fe), cobalt (Co), and molybdenum (Mo), alloys containing these metal elements, and conductive materials such as polysilicon containing impurities. A layered structure of layers containing these elements can also be used. Furthermore, an organic material (conductive polymer) such as poly (3,4-ethylenedioxythiophene) / polystyrene sulfonic acid [PEDOT / PSS] is used as a material constituting the gate electrode, the source / drain electrode, and various wirings. It can also be mentioned.

  These are configured as the method for forming the gate electrode in the present invention, the field effect transistor according to the first aspect, the second aspect, and the fifth aspect of the present invention or the method for forming the source / drain electrode in the manufacturing method thereof. Depending on the material, physical vapor deposition (PVD); various chemical vapor deposition (CVD) including MOCVD; spin coating; screen printing, inkjet printing, offset printing, Various printing methods such as gravure printing method; air doctor coater method, blade coater method, rod coater method, knife coater method, squeeze coater method, reverse roll coater method, transfer roll coater method, gravure coater method, kiss coater method, cast coater method, Spray coater method, slit orifice coater method, calendar Various coating methods such as coater method and dipping method; stamp method; lift-off method; sol-gel method; electrodeposition method; shadow mask method; plating method such as electrolytic plating method, electroless plating method or a combination thereof; A combination of any of these and, if necessary, a patterning technique can be given. In addition, as physical vapor phase growth method (PVD method), (a) various vacuum deposition methods such as electron beam heating method, resistance heating method, flash deposition, (b) plasma deposition method, (c) bipolar sputtering method, DC sputtering method, DC magnetron sputtering method, high frequency sputtering method, magnetron sputtering method, ion beam sputtering method, bias sputtering method and other various sputtering methods, (d) DC (direct current) method, RF method, multi-cathode method, activation Various ion plating methods such as a reaction method, a field evaporation method, a high frequency ion plating method, and a reactive ion plating method can be given.

  In the field effect transistor according to the third aspect or the fourth aspect of the present invention or the method of manufacturing the same, the melting of the channel forming region forming fine particles for forming the source / drain electrodes is performed using, for example, a laser. Alternatively, a method of heating the support with a hot plate, an oven or the like can also be mentioned.

  The method for forming the gate insulating layer depends on the material constituting the gate insulating layer, but the various PVD methods described above; various CVD methods; spin coating methods; the various printing methods described above; the various coating methods described above; the dipping method; Examples thereof include any one of a method; a sol-gel method; an electrodeposition method; a shadow mask method; and a spray method, or various formation methods described in the method for forming a gate electrode.

Alternatively, the gate insulating layer can be formed by oxidizing or nitriding the surface of the gate electrode, or can be obtained by forming an oxide film or a nitride film on the surface of the gate electrode. As a method for oxidizing the surface of the gate electrode, although depending on the material constituting the gate electrode, an oxidation method using O ₂ plasma and an anodic oxidation method can be exemplified. Further, as a method of nitriding the surface of the gate electrode, although it depends on the material constituting the gate electrode, a nitriding method using N ₂ plasma can be exemplified. Alternatively, for example, for an Au electrode, it is immersed by an insulating molecule having a functional group that can form a chemical bond with the gate electrode, such as a linear hydrocarbon modified at one end with a mercapto group. An insulating film can be formed on the surface of the gate electrode by covering the surface of the gate electrode in a self-organized manner by a method such as a method. Alternatively, the gate insulating layer can be formed by modifying the surface of the gate electrode with a silanol derivative (silane coupling agent).

  In the present invention, various glass substrates, various glass substrates having an insulating film formed on the surface, quartz substrates, quartz substrates having an insulating film formed on the surface, and silicon substrates having an insulating film formed on the surface are used as the support. Can be mentioned. Alternatively, as a support, polyethersulfone (PES), polyimide, polycarbonate (PC), polyethylene terephthalate (PET), polymethyl methacrylate (polymethyl methacrylate, PMMA), polyvinyl alcohol (PVA), polyvinyl phenol (PVP) And a plastic film, a plastic sheet and a plastic substrate made of a polymer material exemplified in (1), or mica. By using a support made of such a flexible polymer material, for example, a field effect transistor can be incorporated or integrated into a display device or electronic device having a curved shape. Other examples of the support include a conductive substrate (a substrate made of metal such as gold or aluminum, a substrate made of highly oriented graphite). Further, depending on the configuration and structure of the field effect transistor, the field effect transistor is provided on the support member, but this support member can also be formed of the above-described materials.

  When the field effect transistor of the present invention is applied to and used in a display device or various electronic devices, it may be a monolithic integrated circuit in which a number of field effect transistors are integrated on a support, or each field effect transistor may be cut. It may be individualized and used as a discrete part. The field effect transistor may be sealed with resin. In addition, the field effect transistor of the present invention can be operated as an optical sensor or the like by using a dye that absorbs light near the visible region as an organic semiconductor molecule having a conjugated system. It is.

  In the field effect transistor and the method for manufacturing the same according to the first aspect or the second aspect of the present invention, the underlayer in which the underlayer-constituting particles made of an electrically insulating material are arranged with substantially regularity, or By using as a template a gate insulating layer having a fine particle layer in which gate insulating layer constituent particles made of an electrically insulating material are arranged with substantially regularity, a two-dimensional regular arrangement of channel forming region constituent particles is achieved. Can be made. Therefore, it is difficult for the distance between the channel forming region constituent particles to vary. As a result, there is a channel forming region constituent fine particle in which the channel forming region constituent fine particle and the channel forming region constituent fine particle are not bonded by the organic semiconductor molecule, and the occurrence of the problem that the number of conductive paths is not sufficiently secured is avoided. Therefore, the characteristics of the field effect transistor can be improved and the production stability can be improved.

  In the field effect transistor and the manufacturing method thereof according to the third aspect or the fourth aspect of the present invention, the source / drain electrodes are formed from the layer in which the channel forming region constituting fine particles are melted. Simplification of the formation process of the drain electrode and cost reduction can be realized.

  Furthermore, in the field effect transistor and the method for manufacturing the same according to the fifth aspect of the present invention, any or all of the source / drain electrode, the gate electrode, and the gate insulating layer are made of fine particles, and Since any or all of these are formed from fine particles, the manufacturing process of the entire field effect transistor can be simplified and the cost can be reduced.

  In addition, in the present invention, since the channel forming region constituting fine particles are combined with the organic semiconductor molecule to form a conductive path, the conductive path in the channel forming region constituting fine particle is aligned with the molecular skeleton in the organic semiconductor molecule. A kind of network-like conductive path connected to the conductive path can be formed. Therefore, a structure in which charge transfer in the conductive path occurs predominantly in the axial direction of the molecule along the main chain of the organic semiconductor molecule. Since the conduction path does not include intermolecular electron transfer, the mobility may be limited by intermolecular electron transfer, which was the cause of low mobility in field effect transistors using conventional organic semiconductor materials. Absent. Therefore, the charge transfer in the axial direction in the organic semiconductor molecule can be utilized to the maximum extent. For example, when a molecule having a conjugated system formed along the main chain is used as an organic semiconductor molecule, high mobility due to delocalized π electrons can be used.

  In addition, since the conductive path can be formed one layer at a time in a low temperature process of 200 ° C. or less under normal pressure, a conductive path having a desired thickness can be easily formed, and the field effect type can be formed at low cost. A transistor can be manufactured.

  Hereinafter, the present invention will be described based on examples with reference to the drawings.

  Example 1 relates to a field effect transistor according to the first and fifth aspects of the present invention, and a method of manufacturing the same. A schematic partial cross-sectional view of the field-effect transistor of Example 1 is shown in FIG. 1C, and a conceptual diagram of the conductive path 20 is shown in FIG.

The field effect transistor of Example 1 is specifically a top gate / top contact type TFT, and as shown in a schematic partial cross-sectional view in FIG.
(A) source / drain electrodes 14 formed on the support 11;
(B) a channel forming region 15 formed on a portion of the support 11 located between the source / drain electrode 14 and the source / drain electrode 14;
(C) a gate insulating layer 13 formed on the entire surface (more specifically, on the source / drain electrode 14 and the channel formation region 15), and
(D) a gate electrode 12 formed on the gate insulating layer 13 so as to face the channel formation region 15;
Consists of.

At least between the portion of the support 11 located between the source / drain electrode 14 and the source / drain electrode 14 and the channel forming region 15 (more specifically, in the first embodiment, over the entire surface). An underlayer 30 is formed, and the underlayer 30 is formed by arranging underlayer-constituting fine particles 31 made of an electrically insulating material (specifically, SiO _x fine particles, silica fine particles) with substantially regularity. In Example 1, the base layer 30 composed of the base layer constituting fine particles 31 and the extending portion 15A of the channel forming region 15 are also formed between the source / drain electrodes 14 and the support 11. . In the drawings, the underlayer 30 is illustrated as being composed of one layer composed of the underlayer constituting fine particles 31, but the underlayer 30 is formed by laminating layers composed of the underlayer constituting fine particles 31. You may have a structure. The same applies to Example 2 and Example 5 described later.

  Further, as shown in the conceptual diagram of FIG. 1D, the channel forming region 15 is composed of channel forming region constituting fine particles 21 made of a conductor and organic semiconductor molecules 22 bonded to the channel forming region constituting fine particles 21. The channel forming region constituting fine particles 21 are arranged with substantially regularity based on the fine particle arrangement state of the underlayer 30. In the drawing, the channel forming region 15 is illustrated as being composed of one layer composed of channel forming region constituting particles 21, but the channel forming region 15 is a layer composed of channel forming region constituting particles 21. May have a laminated structure. The same applies to Examples 2 to 6 described later.

In Example 1, gold fine particles (gold nanoparticles) are used as the channel forming region constituting fine particles 21 made of a conductor, and the organic semiconductor molecules 22 are organic semiconductor molecules having a conjugated bond, and thiol groups at both ends of the molecule. 4,4′-biphenyldithiol (BPDT) with (—SH) is used. The gate insulating layer 13 is made of SiO ₂ , the gate electrode 12 and the source / drain electrode 14 are made of copper fine particles, and the support 11 is made of a glass substrate having an insulating film (not shown) formed on the surface.

  FIG. 7A schematically shows a state in which the base layer constituting fine particles 31 are arranged with substantially regularity in Example 1, but the base layer constituting fine particles 31 are positioned at the vertices of an equilateral triangle. Closely arranged in contact. Further, a state in which the channel forming region constituting fine particles 21 are arranged with substantially regularity is schematically shown in FIGS. 8A and 8B or schematically in FIGS. 9A and 9B. .

  The underlayer constituting fine particles 31 are indicated by solid circles in FIGS. 7A and 7B, and FIGS. 8A and 8B, FIGS. 9A and 9B, and FIG. 10 (A) and (B) are indicated by dotted circles. Further, the channel-forming region constituting fine particles 21 are indicated by solid circles in FIGS. 8A and 8B, FIGS. 9A and 9B, and FIGS. 10A and 10B. The semiconductor molecules 22 are indicated by solid line segments in FIG. 8B, FIG. 9B, and FIG.

  Here, since the underlying layer constituting fine particles 31 are densely arranged so as to be located at the apexes of the equilateral triangle, the channel forming region constituting fine particles 21 are located on the normal passing through the center of the equilateral triangle. The channel forming region constituting fine particles 21 are located at the apexes of an equilateral triangle formed by the channel forming region constituting fine particles 21 (see FIG. 8B) or are formed by the channel forming region constituting fine particles 21. It is located at the apex of a regular hexagon (see FIG. 9B). The same applies to Example 2 and Example 5 described later. In order to obtain the state shown in FIG. 8B and the state shown in FIG. 9B, the average particle diameter of the base layer constituting fine particles 31, the average particle diameter of the channel forming region constituting fine particles 21, and the organic semiconductor The lengths of the molecules 22 in the major axis direction are illustrated in Tables 1 and 2 below, respectively.

[Table 1]
Average particle diameter of the underlying layer constituting fine particles 31: 7 nm
Average particle diameter of channel forming region constituting fine particles 21: 5 nm
The length of the organic semiconductor molecule 22 in the major axis direction: 2 nm

[Table 2]
Average particle diameter of the underlying layer constituting fine particles 31: 14 nm
Average particle diameter of channel forming region constituting fine particles 21: 5 nm
Length of major axis direction of organic semiconductor molecule 22: 2 nm

  In Example 1 or Examples 2 to 6 to be described later, the functional group possessed by the organic semiconductor molecule 22 at the terminal is chemically bonded to the channel-forming region constituting fine particles 21. Alternatively, the organic semiconductor molecule 22 is chemically bonded to the channel forming region constituting fine particles 21 by the functional group at the end. More specifically, the functional group which the organic semiconductor molecule 22 has at both ends (in Example 1, it is an organic semiconductor molecule having a conjugated bond, which is a thiol group having both ends of 4,4′-biphenyldithiol (BPDT). The organic semiconductor molecules 22 and the channel-forming region-constituting fine particles 21 are chemically (alternately) bonded by [-SH]), or are three-dimensionally chemically (alternately) bonded to form a network. A conductive path 20 is constructed. The conductive path 20 is constituted by a single layer of a conjugate of the channel forming region constituting fine particles 21 and the organic semiconductor molecules 22, or alternatively, by a laminated structure of the conjugate of the channel forming region constituting fine particles 21 and the organic semiconductor molecules 22. A conductive path 20 is configured.

  The channel forming region constituting fine particles 21 are regularly arranged two-dimensionally on a base layer 30 (or a fine particle layer 50 described later) within a plane substantially parallel to the surface of the base layer 30 (or fine particle layer 50 described later). After the alignment, the single step of bringing the organic semiconductor molecules 22 into contact is performed once, whereby a single layer of a combined body of the channel forming region constituting fine particles 21 and the organic semiconductor molecules 22 can be formed. Thus, a layer composed of a combination of the channel forming region constituting fine particles 21 and the organic semiconductor molecules 22 is laminated, and a laminated structure of the combination can be obtained. Alternatively, the channel forming region constituting fine particles 21 are regularly arranged three-dimensionally by repeating this step a plurality of times, and then the step of contacting the organic semiconductor molecules 22 is performed at least once. It is possible to obtain a laminated structure of a bonded body in which layers formed of a bonded body of the formation region constituting fine particles 21 and the organic semiconductor molecules 22 are stacked.

  That is, in the formation process of the channel formation region 15, after forming one layer of the channel formation region constituting fine particles 21, the organic semiconductor molecules 22 are brought into contact with the channel formation region constituting fine particles 21, thereby By forming a conjugate with the semiconductor molecule 22, one layer of the conjugate is formed. Thus, since the channel formation region 15 can be formed by forming each layer of the combined body, the channel formation region 15 having a desired thickness can be formed by repeating this process. . The channel forming region 15 thus obtained is composed of a combined body in which the channel forming region constituting fine particles 21 and the organic semiconductor molecules 22 are combined in a network shape, and carrier movement is caused by the gate voltage applied to the gate electrode 12. Be controlled. Specifically, for example, when the gate voltage applied to the gate electrode 12 is 0 volt, a source / drain current flows between the source / drain electrodes 14. Furthermore, the source / drain current flowing between the source / drain electrodes 14 can be controlled by controlling the direction (plus or minus) and the value of the gate voltage applied to the gate electrode 12.

  Here, in the channel formation region 15, the channel formation region constituting fine particles 21 are two-dimensionally or three-dimensionally linked by the organic semiconductor molecules 22, and the conductive path in the channel formation region constituting fine particles 21 and the organic semiconductor molecules 22 A network-like conductive path 20 connected to the conductive paths along the molecular skeleton is formed. And, as shown in the conceptual diagram of FIG. 1D, this conductive path 20 does not include the intermolecular electron transfer that was the cause of the low mobility in the channel formation region made of a conventional organic semiconductor, In addition, since the electron movement in the molecule is performed through a conjugated system formed along the molecular skeleton, high mobility is expected. Electron conduction in the channel forming region 15 is performed through the network-like conductive path 20, and the conductivity of the channel forming region 15 is controlled by a gate voltage applied to the gate electrode 12.

  The channel formation region 15 may be a single layer of a combined body, or a stacked structure of a combined body of two or more layers and about ten layers. The thickness of one layer is substantially the same as the particle diameter (several nm) of the channel forming region constituting fine particles. When the channel forming region constituting fine particles 21 are made of gold (Au) having an average particle diameter of about 10 nm and have a laminated structure of 10 layers, the thickness of the channel forming region 15 is approximately 100 nm. In addition, since the channel forming region 15 can be obtained by forming each layer of the bonded body independently, the channel forming region constituting fine particles 21 are formed for each bonded body or for each stacked structure of the bonded body. The characteristics of the channel forming region 15 may be controlled by changing the material to be formed, the average particle size of the channel forming region constituting fine particles 21 and the organic semiconductor molecules 22.

  The matters described above basically apply to Examples 2 to 6 described later.

  Hereinafter, a method for manufacturing the field-effect transistor of Example 1 will be described with reference to FIGS. 1A to 1C which are schematic partial end views of a support and the like.

[Step-100]
First, at least on the portion of the support 11 located between the source / drain electrode 14 and the source / drain electrode 14 (in the first embodiment, on the entire surface of the support 11), an electrically insulating material is used. An underlayer 30 in which the underlayer-constituting fine particles 31 made of SiO _x are arranged with substantially regularity is formed. Specifically, a spin coating method in which a colloidal solution (solvent: cyclohexane) of silica (SiO ₂ ) nanoparticles is dropped so as to cover the entire surface of the support 11 and an excess solution and nanoparticles are removed by a spin coater. Based on this, the underlayer 30 can be formed. FIG. 7A schematically shows a state in which the base layer constituting fine particles 31 thus obtained are arranged with substantially regularity.

[Step-110]
Next, a channel forming region 15 having a conductive path 20 constituted by channel forming region constituting fine particles 21 made of a conductor and organic semiconductor molecules 22 bonded to the channel forming region constituting fine particles 21 on the base layer 30; Then, the extending portion 15A of the channel forming region 15 is formed.

In Example 1, gold nanoparticles having a uniform particle size obtained by improving gold nanoparticles prepared in advance are used. That is, in Example 1, a method proposed by Leff et al. (A method for producing gold nanoparticles using dodecylamine (C ₁₂ H ₂₅ NH ₂ ) as a protective film. DV Leff, et al., Langmuir, 1996, 12, 4723). Applying a modified method of Lin et al. (See XM Lin, et al., J. Nanoparticle Res., 2000, 2, 157) to the colloidal solution of gold nanoparticles. To make the particle size of the gold nanoparticles uniform.

Specifically, gold nanoparticles are obtained by the following preparation method. That is, tetrachloroauric acid (HAuCl ₄ .3H ₂ O) is dissolved in ion exchange water. The solution is then stirred vigorously and tetraoctyl ammonium bromide (N (C ₈ H ₁₇ ) ₄ Br) dissolved in toluene is added to the solution. Then dodecylamine (C ₁₂ H ₂₅ NH ₂ ) dissolved in toluene is added to the mixture. Thereafter, a solution obtained by dissolving sodium borohydride (NaBH ₄ ) in ion-exchanged water is dropped into the vigorously stirred mixture. And after continuing stirring for 12 hours, after leaving still, an aqueous layer is removed with a separatory funnel. Next, toluene and dodecylamine are added to this solution, and the mixture is heated to reflux at 130 ° C. for 1 hour. Then, after leaving still to room temperature, liquid volume is reduced with an evaporator, Then ethanol is added and it leaves still for 12 hours in a freezer. The precipitated gold nanoparticles are separated by filtration, washed with ethanol, and dissolved in toluene. A gold nanoparticle colloidal solution (solvent: toluene) in which 0.05% by weight of gold nanoparticles whose surface is coated with a protective film made of dodecylamine is dispersed.

  And after forming the thin film which consists of the solution containing the channel formation area | region structure fine particle 21 obtained in this way on the base layer 30 by the casting method, the solvent contained in a solution is evaporated. Accordingly, the channel-forming region constituting fine particles 21 can be arranged with substantially regularity based on the fine particle arrangement state of the underlayer 30 (see FIG. 8A or FIG. 9A).

  Next, the conductive path 20 is formed by bonding the organic semiconductor molecules 22 to the channel forming region constituting fine particles 21. Specifically, after immersing the whole in a solution in which organic semiconductor molecule 22 composed of 4,4′-biphenyldithiol is dissolved in toluene at a molar concentration of several mM, the solution is replaced by washing with toluene. Evaporate. At this time, the dodecylamine constituting the protective film is replaced by the organic semiconductor molecule 22 composed of 4,4′-biphenyldithiol, and the organic semiconductor molecule 22 is composed of gold nanoparticles by the thiol group (—SH) at the terminal. It is chemically bonded to the surface of the channel forming region constituting fine particles 21. A large number of organic semiconductor molecules 22 are bonded to the surface of one channel forming region constituting particle 21 so as to enclose the channel forming region constituting particle 21. Some of them are also bonded to other channel-forming region constituting particles 21 by a thiol group at the other molecule end, so that the organic semiconductor molecules 22 make the channel-forming region constituting particles 21 in a two-dimensional network form. A connected state can be obtained (see FIG. 8B or FIG. 9B).

  In this way, the organic semiconductor molecules 22 and the channel forming region constituting fine particles 21 are chemically (alternatively) bonded to each other by the functional groups of the organic semiconductor molecules 22 at both ends, whereby the network-like conductive path 20 is constructed. In the state shown in FIG. 1A, the conductive path 20 is constructed by a single layer of a combination of the channel forming region constituting fine particles 21 and the organic semiconductor molecules 22.

[Step-120]
Next, if necessary, [Step-110] is repeated a desired number of times. In this way, the organic semiconductor molecule 22 and the channel-forming region-constituting fine particles 21 are three-dimensionally chemically (alternately) bonded by the functional groups of the organic semiconductor molecule 22 at both ends, thereby constructing the network-like conductive path 20. As a result, it is possible to obtain a structure in which the conductive path 20 is constituted by a laminated structure of a combined body of the channel forming region constituting fine particles 21 and the organic semiconductor molecules 22.

[Step-130]
Thereafter, a copper paste containing copper fine particles is printed on the extending portion 15A of the channel forming region 15 by screen printing and baked, whereby the source / drain electrodes 14 can be formed (FIG. 1). (See (B)).

[Step-140]
Thereafter, the gate insulating layer 13 is formed on the entire surface (more specifically, on the source / drain electrode 14 and the channel formation region 15). Specifically, the gate insulating layer 13 made of SiO ₂ is formed on the entire surface based on the sputtering method.

[Step-150]
Next, a copper paste containing copper fine particles is printed on the gate insulating layer 13 by a screen printing method and baked, whereby the gate electrode 12 can be formed (see FIG. 1C).

[Step-160]
Finally, an insulating layer (not shown) as a passivation film is formed on the entire surface, an opening is formed in the insulating layer above the source / drain electrode 14, and a wiring material layer is formed on the entire surface including the inside of the opening. By patterning the wiring material layer, the field effect transistor of Example 1 in which wiring (not shown) connected to the source / drain electrode 14 is formed on the insulating layer can be completed.

  The second embodiment is a modification of the first embodiment. The field effect transistor of Example 2 is different from the field effect transistor of Example 1 in that the field effect transistor of Example 1 is a top gate / top contact type TFT. The second field effect transistor is a top gate / bottom contact type TFT. Other points are the same as those of the field effect transistor described in the first embodiment.

That is, the field effect transistor of Example 2 is specifically a top gate / bottom contact type TFT, and as shown in a schematic partial sectional view in FIG.
(A) source / drain electrodes 14 formed on the support 11;
(B) a channel forming region 15 formed on a portion of the support 11 located between the source / drain electrode 14 and the source / drain electrode 14;
(C) a gate insulating layer 13 formed on the entire surface (more specifically, on the source / drain electrode 14 and the channel formation region 15), and
(D) a gate electrode 12 formed on the gate insulating layer 13 so as to face the channel formation region 15;
Consists of.

  At least between the portion of the support 11 located between the source / drain electrode 14 and the source / drain electrode 14 and the channel formation region 15 (more specifically, in the second embodiment, the source A base layer 30 is formed between the channel forming region 15 and the portion of the support 11 located between the / drain electrode 14 and the source / drain electrode 14, and the base layer 30 is made of an electrically insulating material. The underlying layer constituting fine particles 31 are arranged with substantially regularity.

  The channel formation region 15 in the second embodiment has the same configuration and structure as the channel formation region 15 described in the first embodiment. Further, similarly to the first embodiment, the channel forming region constituting fine particles 21 are arranged with substantially regularity based on the fine particle arrangement state of the underlayer 30. Moreover, since the material which comprises the field effect transistor of Example 2 can be made the same as the material which comprises the field effect transistor of Example 1, detailed description is abbreviate | omitted.

  Hereinafter, a method for manufacturing the field effect transistor of Example 2 will be described with reference to FIGS. 2A to 2C which are schematic partial end views of the support and the like.

[Step-200]
First, in the same manner as in [Step-130] in Example 1, a copper paste containing copper fine particles is printed on the support 11 by screen printing and baked, whereby the source / drain electrodes 14 are formed. It can be formed (see FIG. 2A).

[Step-210]
Thereafter, in the same manner as in [Step-100] of Example 1, the base layer 30 is formed on the portion of the support 11 located between the source / drain electrode 14 and the source / drain electrode 14.

[Step-220]
Next, in the same manner as in [Step-110] to [Step-120] of Example 1, the channel forming region constituting fine particles 21 made of a conductor and the channel forming region constituting fine particles 21 are combined on the underlayer 30. A channel forming region 15 having a conductive path 20 constituted by the organic semiconductor molecules 22 is formed (see FIG. 2B).

[Step-230]
Thereafter, the gate insulating layer 13 and the gate electrode 12 are formed in the same manner as in [Step-140] and [Step-150] in Example 1 (see FIG. 2C). The field effect transistor of Example 2 is completed in the same manner as [Step-160] of Example 1.

  In some cases, the removal of the underlying layer 30 on the source / drain electrode 14 in [Step-210] and the removal of the conductive path 20 on the source / drain electrode 14 in [Step-220] are unnecessary. On the drain electrode 14, the base layer 30 and the extended portion of the channel formation region 15 may be left.

  Example 3 relates to a field-effect transistor according to the second and fifth aspects of the present invention and a method for manufacturing the same. A schematic partial sectional view of the field effect transistor of Example 3 is shown in FIG.

The field effect transistor of Example 3 is specifically a bottom gate / top contact type TFT, and as shown in a schematic partial cross-sectional view in FIG.
(A) a gate electrode 12 formed on the support 11;
(B) a gate insulating layer 43 formed on the gate electrode 12 and the support 11;
(C) the source / drain electrode 14 formed on the gate insulating layer 43, and
(D) a channel formation region 15 formed on the portion of the gate insulating layer 43 located between the source / drain electrode 14 and the source / drain electrode 14 so as to face the gate electrode 12;
Consists of.

The gate insulating layer 43 includes a fine particle layer 50 in which gate insulating layer constituting fine particles 51 made of an electrically insulating material (specifically, SiO _x fine particles, silica fine particles) are arranged with substantially regularity. The gate insulating layer 43 has a two-layer structure including a fine particle layer 50 and a film-like layer (lower gate insulating film 43A made of SiO ₂ ). In the third embodiment, the extending portion 15 </ b> A of the channel forming region 15 is also formed between the source / drain electrode 14 and the gate insulating layer 43. In the drawing, the fine particle layer 50 is illustrated as being composed of one layer composed of the gate insulating layer constituting fine particles 51. However, the fine particle layer 50 is formed by laminating layers composed of the gate insulating layer constituting fine particles 51. Rather, the fine particle layer 50 preferably has a structure in which layers of the gate insulating layer constituting fine particles 51 are laminated. The same applies to Example 4 and Example 6 described later.

  Similarly to the conceptual diagram shown in FIG. 1D, the channel forming region 15 is composed of channel forming region constituting fine particles 21 made of a conductor and organic semiconductor molecules 22 bonded to the channel forming region constituting fine particles 21. Based on the fine particle arrangement state of the fine particle layer 50, the channel forming region constituting fine particles 21 are arranged with substantially regularity.

  Since the material constituting the field effect transistor of Example 3 can be the same as the material constituting the field effect transistor of Example 1, detailed description thereof is omitted.

  FIG. 7A schematically shows a state in which the gate insulating layer constituting fine particles 51 are arranged with substantially regularity in Example 3, and the gate insulating layer constituting fine particles 51 are located at the vertices of an equilateral triangle. Are arranged in close contact with each other. Further, a state in which the channel forming region constituting fine particles 21 are arranged with substantially regularity is schematically shown in FIGS. 8A and 8B or schematically in FIGS. 9A and 9B. . The fine particles 51 constituting the gate insulating layer are shown by solid circles in FIGS. 7A and 7B, and FIGS. 8A and 8B, FIGS. 9A and 9B, In FIGS. 10A and 10B, a dotted circle is shown.

  Here, since the fine particles 51 constituting the gate insulating layer are densely arranged so as to be located at the vertices of the equilateral triangle, the fine particles 21 constituting the channel forming region are located on the normal passing through the center of the equilateral triangle. The channel forming region constituting fine particles 21 are located at the apexes of an equilateral triangle formed by the channel forming region constituting fine particles 21 (see FIG. 8B) or are formed by the channel forming region constituting fine particles 21. It is located at the apex of a regular hexagon (see FIG. 9B). The same applies to Example 4 and Example 6 described later. In order to obtain the state shown in FIG. 8B and the state shown in FIG. 9B, the average particle diameter of the fine particles 51 constituting the gate insulating layer, the average particle diameter of the fine particles 21 constituting the channel formation region, and the organic The lengths of the semiconductor molecules 22 in the major axis direction may be the same as those exemplified in Table 1 and Table 2, respectively. In Tables 1 and 2, “the average particle diameter of the base layer constituting fine particles 31” may be read as “the average particle diameter of the gate insulating layer constituting fine particles 51”.

  Hereinafter, with reference to FIGS. 3A and 3B which are schematic partial end views of the support and the like, a method for manufacturing the field effect transistor of Example 3 will be described.

[Step-300]
First, after forming the gate electrode 12 on the support 11 in the same manner as in [Step-150] in Example 1, the gate electrode 12 is supported and supported in the same manner as in [Step-140] in Example 1. A lower gate insulating film 43A made of SiO ₂ is formed on the body 11.

[Step-310]
Thereafter, in the same manner as in [Step-100] in Example 1, the fine particle layer 50 in which the gate insulating layer constituting fine particles 51 made of SiO _x are arranged with substantially regularity is formed on the lower gate insulating film 43A.

[Step-320]
Next, in the same manner as in [Step-110] to [Step-120] of Example 1, on the fine particle layer 50, the channel forming region constituting fine particles 21 made of a conductor and the channel forming region constituting fine particles 21 are bonded. The channel forming region 15 having the conductive path 20 constituted by the organic semiconductor molecules 22 and the extending portion 15A of the channel forming region 15 are formed (see FIG. 3A).

[Step-330]
Thereafter, in the same manner as in [Step-130] in Example 1, the source / drain electrodes 14 are formed on the extending portions 15A of the channel forming region 15 (see FIG. 3B).

[Step-340]
Finally, an insulating layer (not shown) as a passivation film is formed on the entire surface, an opening is formed in the insulating layer above the source / drain electrode 14, and a wiring material layer is formed on the entire surface including the inside of the opening. By patterning the wiring material layer, the field effect transistor of Example 3 in which the wiring (not shown) connected to the source / drain electrode 14 is formed on the insulating layer can be completed.

  The fourth embodiment is a modification of the third embodiment. The field effect transistor of Example 4 is different from the field effect transistor of Example 3 in that the field effect transistor of Example 3 is a bottom gate / top contact type TFT. The field effect transistor No. 4 is a bottom gate / bottom contact type TFT. Other points are the same as those of the field effect transistor described in the third embodiment.

That is, the field effect transistor of Example 4 is specifically a bottom-gate / bottom-contact TFT, and a schematic partial cross-sectional view is shown in FIG.
(A) a gate electrode 12 formed on the support 11;
(B) a gate insulating layer 43 formed on the gate electrode 12 and the support 11;
(C) the source / drain electrode 14 formed on the gate insulating layer 43, and
(D) a channel formation region 15 formed on the portion of the gate insulating layer 43 located between the source / drain electrode 14 and the source / drain electrode 14 so as to face the gate electrode 12;
Consists of.

As in the third embodiment, the gate insulating layer 43 includes a fine particle layer in which the fine particles 51 constituting the gate insulating layer made of an electrically insulating material (specifically, SiO _x fine particles, silica fine particles) are arranged with substantially regularity. 50. The gate insulating layer 43 has a two-layer structure including a fine particle layer 50 and a film-like layer (lower gate insulating film 43A made of SiO ₂ ). In the fourth embodiment, the source / drain electrode 14 is formed directly on the gate insulating layer 43.

  The channel formation region 15 in the fourth embodiment has the same configuration and structure as the channel formation region 15 described in the first embodiment. Further, similarly to the third embodiment, the channel forming region constituting fine particles 21 are arranged with substantially regularity based on the fine particle arrangement state of the fine particle layer 50. Moreover, since the material which comprises the field effect transistor of Example 4 can be made the same as the material which comprises the field effect transistor of Example 3, detailed description is abbreviate | omitted.

  Hereinafter, with reference to FIGS. 4A to 4C which are schematic partial end views of the support and the like, a method for manufacturing the field-effect transistor of Example 4 will be described.

[Step-400]
First, after forming the gate electrode 12 on the support 11 in the same manner as in [Step-150] in Example 1, the gate electrode 12 is supported and supported in the same manner as in [Step-140] in Example 1. A lower gate insulating film 43A made of SiO ₂ is formed on the body 11.

[Step-410]
Thereafter, in the same manner as in [Step-100] of Example 1, the fine particle layer 50 in which the gate insulating layer constituting fine particles 51 made of SiO _x are arranged with substantially regularity is formed on the lower gate insulating film 43A (see FIG. (See (A) of FIG. 4).

[Step-420]
Thereafter, in the same manner as in [Step-130] of Example 1, the source / drain electrodes 14 are formed on the gate insulating layer 43 (more specifically, on the fine particle layer 50) ((B in FIG. 4). )reference).

[Step-430]
Next, in the same manner as in [Step-220] in Example 2, on the fine particle layer 50, the channel forming region constituting fine particles 21 made of a conductor, and the organic semiconductor molecules 22 bonded to the channel forming region constituting fine particles 21 are provided. A channel formation region 15 having a conductive path 20 constituted by the above is formed (see FIG. 4C).

[Step-440]
Finally, an insulating layer (not shown) as a passivation film is formed on the entire surface, an opening is formed in the insulating layer above the source / drain electrode 14, and a wiring material layer is formed on the entire surface including the inside of the opening. By patterning the wiring material layer, the field effect transistor of Example 4 in which wiring (not shown) connected to the source / drain electrode 14 is formed on the insulating layer can be completed.

  Example 5 relates to the field effect transistor according to the third aspect, the first aspect, and the fifth aspect of the present invention, and the manufacturing method thereof. A schematic partial sectional view of the field-effect transistor of Example 5 is shown in FIG.

The field effect transistor of Example 5 is specifically a top-gate TFT, and a schematic partial cross-sectional view is shown in FIG.
(A) a source / drain electrode 64 formed on the support 11;
(B) a channel forming region 15 formed on the portion of the support 11 located between the source / drain electrode 64 and the source / drain electrode 64;
(C) the gate insulating layer 13 formed on the source / drain electrode 64 and the channel forming region 15, and
(D) a gate electrode 12 formed on the gate insulating layer 13 so as to face the channel formation region 15;
Consists of.

  The channel forming region 15 is composed of a channel forming region constituting fine particle 21 made of a conductor and an organic semiconductor molecule 22 bonded to the channel forming region constituting fine particle 21 as shown in FIG. A conductive path 20 is provided.

  In the fifth embodiment, the source / drain electrode 64 is composed of a layer in which the channel forming region constituting fine particles 21 are melted.

Even in the fifth embodiment, although not indispensable, at least between the portion of the support 11 located between the source / drain electrode 64 and the source / drain electrode 64 and the channel forming region 15 (implementation). In Example 5, more specifically, the underlayer 30 is formed over the entire surface, and the underlayer 30 is an underlayer-constituting fine particle made of an electrically insulating material (specifically, SiO _x fine particles, silica fine particles). It is preferable that 31 is arranged with substantially regularity. By adopting such a configuration, the channel forming region constituting fine particles 21 can be arranged with substantially regularity based on the fine particle arrangement state of the underlayer 30 as in the first embodiment. In the fifth embodiment, an underlayer 30 composed of the underlayer constituting fine particles 31 is also formed between the source / drain electrode 64 and the support 11 as in the first embodiment.

  The channel formation region 15 in the fifth embodiment has the same configuration and structure as the channel formation region 15 described in the first embodiment. Moreover, since the material which comprises the field effect transistor of Example 5 can be made the same as the material which comprises the field effect transistor of Example 1, detailed description is abbreviate | omitted.

  Hereinafter, with reference to FIGS. 5A to 5C which are schematic partial end views of the support and the like, a method for manufacturing the field-effect transistor of Example 5 will be described.

[Step-500]
First, the underlayer 30 is formed on the support 11 in the same manner as in [Step-100] of Example 1.

[Step-510]
Next, in the same manner as in [Step-110] to [Step-120] of Example 1, the channel forming region constituting fine particles 21 made of a conductor and the channel forming region constituting fine particles 21 were combined on the underlayer 30. A channel forming region 15 having a conductive path 20 constituted by organic semiconductor molecules 22 is formed (see FIG. 5A).

[Step-520]
Thereafter, the layer (channel formation region extension portion 15A) is formed by irradiating the layer (channel formation region extension portion 15A) composed of the channel formation region constituting fine particles 21 in the region where the source / drain electrode 64 is to be formed. ) (More specifically, the channel forming region constituting fine particles 21 are melted and the organic semiconductor molecules 22 are evaporated) to form the source / drain electrodes 64 (see FIG. 5B).

[Step-530]
Next, in the same manner as in [Step-140] and [Step-150] of Example 1, over the entire surface (more specifically, on the source / drain electrode 64 and on the channel formation region 15). After the gate insulating layer 13 is formed, a copper paste containing copper fine particles is printed on the gate insulating layer 13 by a screen printing method and fired to form the gate electrode 12 ((C in FIG. 5). )reference).

[Step-540]
Finally, an insulating layer (not shown) as a passivation film is formed on the entire surface, an opening is formed in the insulating layer above the source / drain electrode 64, and a wiring material layer is formed on the entire surface including the inside of the opening. By patterning the wiring material layer, the field effect transistor of Example 5 in which the wiring (not shown) connected to the source / drain electrode 64 is formed on the insulating layer can be completed.

  [Step-500], [Step-520], [Step-510], [Step-530], and [Step-540] may be changed in this order.

  Example 6 relates to a field effect transistor according to the fourth, second, and fifth aspects of the present invention, and a method of manufacturing the same. A schematic partial cross-sectional view of the field effect transistor of Example 6 is shown in FIG.

The field effect transistor of Example 6 is specifically a bottom gate type TFT, and a schematic partial cross-sectional view is shown in FIG.
(A) a gate electrode 12 formed on the support 11;
(B) a gate insulating layer 13 formed on the gate electrode 12 and the support 11;
(C) a source / drain electrode 64 formed on the gate insulating layer 13, and
(D) a channel forming region 15 formed on the portion of the gate insulating layer 13 positioned between the source / drain electrode 64 and the source / drain electrode 64 so as to face the gate electrode 12;
Consists of.

  The channel forming region 15 is composed of a channel forming region constituting fine particle 21 made of a conductor and an organic semiconductor molecule 22 bonded to the channel forming region constituting fine particle 21 as shown in FIG. A conductive path 20 is provided.

  Also in the sixth embodiment, the source / drain electrode 64 is formed of a layer in which the channel forming region constituting fine particles 21 are melted, as in the fifth embodiment.

Even in the sixth embodiment, although not essential, the gate insulating layer 43 is composed of the gate insulating layer constituting fine particles 51 made of an electrically insulating material (specifically, SiO _x fine particles, silica fine particles). It is preferable to have a fine particle layer 50 arranged in the same manner. By adopting such a structure, the channel forming region constituting fine particles 21 can be arranged with substantially regularity based on the fine particle arrangement state of the fine particle layer 50 as in the third embodiment. The gate insulating layer 43 has a two-layer structure including a fine particle layer 50 and a film-like layer (lower gate insulating film 43A made of SiO ₂ ).

  The channel formation region 15 in Example 6 has the same configuration and structure as the channel formation region 15 described in Example 1. Moreover, since the material which comprises the field effect transistor of Example 6 can be made the same as the material which comprises the field effect transistor of Example 3, detailed description is abbreviate | omitted.

  Hereinafter, with reference to FIGS. 6A and 6B which are schematic partial end views of the support and the like, a method for manufacturing the field-effect transistor of Example 6 will be described.

[Step-600]
First, after forming the gate electrode 12 on the support 11 in the same manner as in [Step-150] in Example 1, the gate electrode 12 is supported and supported in the same manner as in [Step-140] in Example 1. A lower gate insulating film 43A made of SiO ₂ is formed on the body 11.

[Step-610]
Thereafter, in the same manner as in [Step-100] in Example 1, the fine particle layer 50 in which the gate insulating layer constituting fine particles 51 made of SiO _x are arranged with substantially regularity is formed on the lower gate insulating film 43A.

[Step-620]
Next, in the same manner as in [Step-110] to [Step-120] of Example 1, on the fine particle layer 50, the channel forming region constituting fine particles 21 made of a conductor and the channel forming region constituting fine particles 21 are bonded. A channel forming region 15 having a conductive path 20 constituted by the organic semiconductor molecules 22 is formed (see FIG. 6A).

[Step-630]
Thereafter, the layer (channel formation region extension portion 15A) is formed by irradiating the layer (channel formation region extension portion 15A) composed of the channel formation region constituting fine particles 21 in the region where the source / drain electrode 64 is to be formed. ) Is melted (more specifically, the channel-forming region constituting fine particles 21 are melted and the organic semiconductor molecules 22 are evaporated) to form the source / drain electrodes 64 (see FIG. 6B).

[Step-640]
Finally, an insulating layer (not shown) as a passivation film is formed on the entire surface, an opening is formed in the insulating layer above the source / drain electrode 64, and a wiring material layer is formed on the entire surface including the inside of the opening. By patterning the wiring material layer, the field effect transistor of Example 6 in which the wiring (not shown) connected to the source / drain electrode 64 is formed on the insulating layer can be completed.

  [Step-600], [Step-610], [Step-630], [Step-620], [Step-640] may be changed in this order.

  As mentioned above, although this invention was demonstrated based on the preferable Example, this invention is not limited to these Examples. The structure and configuration of the field-effect transistor, the manufacturing conditions, and the specific manufacturing method are examples, and can be changed as appropriate. When the field effect transistor (TFT) obtained by the present invention is applied to and used in a display device or various electronic devices, a monolithic integrated circuit in which a large number of TFTs are integrated on a support or a support member may be used. The TFT may be cut and individualized and used as a discrete component. The channel forming region constituting fine particles are not limited to gold (Au), but may be composed of other metals (for example, silver or platinum), or cadmium sulfide, cadmium selenide, or silicon as a semiconductor. . Further, the organic semiconductor molecule is not limited to 4,4'-biphenyldithiol (BPDT).

  Depending on the surface properties of the underlying layer constituting particles and the gate insulating layer constituting particles, the underlying layer constituting particles and the gate insulating layer constituting particles are positioned at the vertices of the square as shown in FIG. It can also be arranged in close contact. In this case, as shown in FIGS. 10A and 10B, the channel forming region constituting fine particles are located on the normal line passing through the center of the square, and the channel forming region constituting fine particles are formed in the channel forming region. Located at the apex of a square formed by constituent particles.

  In Example 3, Example 4, and Example 6, the gate insulating layer 43 has a two-layer configuration of the fine particle layer 50 and the lower gate insulating film 43A. However, such a configuration is not essential, and the gate insulating layer 43 is not provided. It can also be configured only from the fine particle layer 50.

1A, 1B, and 1C are schematic partial end views of a support and the like for explaining the method of manufacturing the field-effect transistor of Example 1, and FIG. D) is a conceptual diagram of a conductive path constituted by channel-forming region-constituting fine particles and organic semiconductor molecules. 2A, 2 </ b> B, and 2 </ b> C are schematic partial end views of a support and the like for explaining the method for manufacturing the field-effect transistor of Example 2. FIG. 3A and 3B are schematic partial end views of a support and the like for explaining the method for producing the field-effect transistor of Example 3. FIG. 4A, 4 </ b> B, and 4 </ b> C are schematic partial end views of a support and the like for describing the method for manufacturing the field-effect transistor of Example 4. FIG. FIGS. 5A, 5 </ b> B, and 5 </ b> C are schematic partial end views of a support and the like for describing the method for manufacturing the field-effect transistor of Example 5. FIGS. 6A and 6B are schematic partial end views of a support and the like for explaining the method for producing the field-effect transistor of Example 6. FIG. FIGS. 7A and 7B are diagrams schematically showing a state in which the base layer constituting fine particles are arranged with substantially regularity. FIGS. 8A and 8B are diagrams schematically showing a state in which channel-forming region-constituting fine particles are arranged with substantially regularity. FIGS. 9A and 9B are diagrams schematically showing a state in which channel-forming region-constituting particles are arranged with substantially regularity. (A) and (B) of FIG. 10 are diagrams schematically showing a state in which the channel forming region constituting fine particles are arranged with substantially regularity.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Support body, 12 ... Gate electrode, 13, 43 ... Gate insulating layer, 14, 64 ... Source / drain electrode, 15 ... Channel formation region, 15A ... Channel formation region 20 ... conductive path, 21 ... channel forming region constituting fine particles, 22 ... organic semiconductor molecules, 30 ... underlying layer, 31 ... underlying layer constituting fine particles, 43A ... Lower gate insulating film, 50 ... fine particle layer, 51 ... gate insulating layer constituting fine particles

Claims (18)

(A) source / drain electrodes formed on a support;
(B) a channel formation region formed on a portion of the support located between the source / drain electrodes and the source / drain electrodes;
(C) a gate insulating layer formed on the entire surface, and
(D) a gate electrode formed on the gate insulating layer so as to face the channel formation region;
A field effect transistor comprising:
An underlayer is formed at least between the portion of the support located between the source / drain electrode and the source / drain electrode and the channel formation region,
The underlayer is composed of underlayer-constituting particles made of an electrically insulating material arranged with substantially regularity.
The channel forming region has a channel formed by a conductor or a semiconductor, and has a conductive path formed by organic semiconductor molecules bonded to the channel forming region forming particle.
A field effect transistor characterized in that channel-forming region-constituting fine particles are arranged with substantially regularity based on the fine particle arrangement state of the underlayer. (A) a gate electrode formed on a support;
(B) a gate insulating layer formed on the gate electrode and on the support;
(C) a source / drain electrode formed on the gate insulating layer, and
(D) a channel formation region formed on the portion of the gate insulating layer located between the source / drain electrode and the source / drain electrode, facing the gate electrode;
A field effect transistor comprising:
The gate insulating layer includes a fine particle layer in which the fine particles constituting the gate insulating layer made of an electrically insulating material are arranged with substantially regularity,
The channel forming region has a channel formed by a conductor or a semiconductor, and has a conductive path formed by organic semiconductor molecules bonded to the channel forming region forming particle.
A field-effect transistor characterized in that channel-forming region-constituting fine particles are arranged with substantially regularity based on the fine particle arrangement state of the fine particle layer. (A) source / drain electrodes formed on a support;
(B) a channel formation region formed on a portion of the support located between the source / drain electrodes and the source / drain electrodes;
(C) a gate insulating layer formed on the source / drain electrode and the channel formation region; and
(D) a gate electrode formed on the gate insulating layer so as to face the channel formation region;
A field effect transistor comprising:
The channel forming region has a conductive path constituted by channel forming region constituting fine particles made of a conductor and organic semiconductor molecules bonded to the channel forming region constituting fine particles,
The field effect transistor according to claim 1, wherein the source / drain electrodes are formed of a layer in which fine particles forming the channel forming region are melted. (A) a gate electrode formed on a support;
(B) a gate insulating layer formed on the gate electrode and on the support;
(C) a source / drain electrode formed on the gate insulating layer, and
(D) a channel formation region formed on the portion of the gate insulating layer located between the source / drain electrode and the source / drain electrode, facing the gate electrode;
A field effect transistor comprising:
The channel forming region has a conductive path constituted by channel forming region constituting fine particles made of a conductor and organic semiconductor molecules bonded to the channel forming region constituting fine particles,
The field effect transistor according to claim 1, wherein the source / drain electrodes are formed of a layer in which fine particles forming the channel forming region are melted. A field effect transistor comprising a gate electrode, a gate insulating layer, a source / drain electrode, and a channel formation region,
The channel forming region has a channel formed by a conductor or a semiconductor, and has a conductive path formed by organic semiconductor molecules bonded to the channel forming region forming particle.
1. A field effect transistor, wherein any or all of a source / drain electrode, a gate electrode, and a gate insulating layer are made of fine particles.   6. The field effect transistor according to any one of claims 1 to 5, wherein the functional group at the terminal of the organic semiconductor molecule is chemically bonded to the channel forming region constituting fine particles.   The channel-forming region constituting fine particles are made of gold, silver, platinum, copper, aluminum, palladium, chromium, nickel, or iron as a conductor, or an alloy made of these metals. The field effect transistor according to any one of claims 1 to 5.   The channel forming region constituting fine particles are made of cadmium sulfide, cadmium selenide, cadmium telluride, gallium arsenide, titanium oxide, or silicon as a semiconductor, according to any one of claims 1 to 5. The field effect transistor described. The organic semiconductor molecule is an organic semiconductor molecule having a conjugated bond, and at both ends of the molecule, a thiol group (—SH), an amino group (—NH ₂ ), an isocyano group (—NC), a cyano group (—CN), The field effect transistor according to claim 1, which has a thioacetoxyl group (—SCOCH ₃ ) or a carboxyl group (—COOH). (A) source / drain electrodes formed on a support;
(B) a channel formation region formed on a portion of the support located between the source / drain electrodes and the source / drain electrodes;
(C) a gate insulating layer formed on the entire surface, and
(D) a gate electrode formed on the gate insulating layer so as to face the channel formation region;
A method of manufacturing a field effect transistor comprising:
Forming a base layer in which base layer-constituting particles made of an electrically insulating material are arranged with substantially regularity on at least a portion of the support located between the source / drain electrode and the source / drain electrode; ,
Forming a channel forming region having a conductive path constituted by channel-forming region-constituting particles made of a conductor or semiconductor and organic semiconductor molecules bonded to the channel-forming region-constituting fine particles on the underlayer;
Including
A method for producing a field-effect transistor, characterized in that channel-forming region-constituting fine particles are arranged with substantially regularity based on a fine particle arrangement state of an underlayer. (A) a gate electrode formed on a support;
(B) a gate insulating layer formed on the gate electrode and on the support;
(C) a source / drain electrode formed on the gate insulating layer, and
(D) a channel formation region formed on the portion of the gate insulating layer located between the source / drain electrode and the source / drain electrode, facing the gate electrode;
A method of manufacturing a field effect transistor comprising:
Forming a gate insulating layer comprising a fine particle layer in which fine particles constituting a gate insulating layer made of an electrically insulating material are arranged with substantially regularity on a gate electrode and a support;
Forming a channel forming region having a conductive path constituted by channel forming region constituting fine particles made of a conductor or a semiconductor and organic semiconductor molecules combined with the channel forming region constituting fine particles on the fine particle layer;
Including
A method for producing a field-effect transistor, characterized in that channel-forming region-constituting particles are arranged with substantially regularity based on the particle arrangement state of the particle layer. (A) source / drain electrodes formed on a support;
(B) a channel formation region formed on a portion of the support located between the source / drain electrodes and the source / drain electrodes;
(C) a gate insulating layer formed on the source / drain electrode and the channel formation region; and
(D) a gate electrode formed on the gate insulating layer so as to face the channel formation region;
A method of manufacturing a field effect transistor comprising:
After forming a layer composed of channel-forming region-constituting particles made of a conductor on a support,
The source / drain electrode is formed by melting the layer composed of the channel forming region constituting fine particles in the region where the source / drain electrode is to be formed, and the organic semiconductor is formed in the layer constituted of the channel forming region constituting fine particles. Forming a channel forming region having a conductive path constituted by channel forming region constituting fine particles and organic semiconductor molecules bonded to the channel forming region constituting fine particles by contacting molecules.
The manufacturing method of the field effect transistor characterized by including a process. (A) a gate electrode formed on a support;
(B) a gate insulating layer formed on the gate electrode and on the support;
(C) a source / drain electrode formed on the gate insulating layer, and
(D) a channel formation region formed on the portion of the gate insulating layer located between the source / drain electrode and the source / drain electrode, facing the gate electrode;
A method of manufacturing a field effect transistor comprising:
After forming a layer composed of channel forming region constituting fine particles made of a conductor on the gate insulating layer,
The source / drain electrode is formed by melting the layer composed of the channel forming region constituting fine particles in the region where the source / drain electrode is to be formed, and the organic semiconductor is formed in the layer constituted of the channel forming region constituting fine particles. Forming a channel forming region having a conductive path constituted by channel forming region constituting fine particles and organic semiconductor molecules bonded to the channel forming region constituting fine particles by contacting molecules.
The manufacturing method of the field effect transistor characterized by including a process. An organic semiconductor comprising a gate electrode, a gate insulating layer, a source / drain electrode, and a channel formation region, wherein the channel formation region is composed of channel formation region constituting fine particles made of a conductor or a semiconductor, and the channel formation region constituting fine particles. A method of manufacturing a field effect transistor having a conductive path composed of molecules,
A method for manufacturing a field effect transistor, wherein any or all of a source / drain electrode, a gate electrode, and a gate insulating layer are formed from fine particles.   15. The method of manufacturing a field effect transistor according to claim 10, wherein the organic semiconductor molecule is chemically bonded to the channel-forming region constituting fine particles by a functional group at a terminal thereof. .   The channel-forming region constituting fine particles are made of gold, silver, platinum, copper, aluminum, palladium, chromium, nickel, or iron as a conductor, or an alloy made of these metals. The method for producing a field effect transistor according to any one of claims 10 to 14.   The channel forming region constituting fine particles are made of cadmium sulfide, cadmium selenide, cadmium telluride, gallium arsenide, titanium oxide, or silicon as a semiconductor, according to any one of claims 10 to 12. The manufacturing method of the field effect transistor of description. The organic semiconductor molecule is an organic semiconductor molecule having a conjugated bond, and at both ends of the molecule, a thiol group (—SH), an amino group (—NH ₂ ), an isocyano group (—NC), a cyano group (—CN), The method for producing a field effect transistor according to claim 10, which has a thioacetoxyl group (—SCOCH ₃ ) or a carboxyl group (—COOH).

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