JP2009177214A - Method of manufacturing field effect transistor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a field effect transistor for surely forming source/drain electrodes made of a metal single layer film with good adhesiveness on a gate insulating film. <P>SOLUTION: The method of manufacturing a field effect transistor includes: (A) a step of applying silane coupling treatment on a surface of a substrate 11; (B) a step of forming a gate electrode 12 on the substrate 11 subjected to silane coupling treatment; (C) a step of forming a gate insulating film 13 on the gate electrode 12; (D) a step of applying silane coupling treatment on a surface of the gate insulating film 13; (E) a step of forming source/drain electrodes 14 made of a metal single layer film on the gate insulating film 13 subjected to silane coupling treatment; and (F) a step of forming a channel forming region 15 made of a semiconductor material layer on the gate insulating film 13 between the source/drain electrodes 14. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

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

In a semiconductor device, forming a wiring or an electrode made of gold (Au), platinum (Pt) or the like (hereinafter sometimes referred to as a metal layer) directly on an insulating film made of SiO ₂ This is difficult because the adhesion between the metal layer and the metal layer is low. Therefore, usually, an adhesion layer made of titanium (Ti) or chromium (Cr) is formed between the insulating film and the metal layer to prevent the metal layer from peeling from the insulating film.

  However, in such a multilayer structure of the metal layer and the adhesion layer, the controllability of patterning of the metal layer and the adhesion layer may deteriorate due to the difference in etching conditions. Further, since the adhesion layer is formed, an increase in manufacturing cost of the semiconductor device such as an increase in raw material costs and an increase in manufacturing processes is caused. Furthermore, when the channel formation region constituting the semiconductor device is in contact with both the source / drain electrodes made of gold (Au) and the adhesion layer made of titanium (Ti), the space between titanium (Ti) and the channel is between It has been observed that the channel mobility of the entire transistor is reduced due to the movement of electric charges.

Accordingly, an object of the present invention, for example, a metal single-layer film forming method capable of reliably forming the adhesion good metal single-layer film on a substrate made of SiO _2, for example, good adhesion wiring on a substrate of SiO ₂ And a method of manufacturing a field effect transistor capable of reliably forming a source / drain electrode composed of a metal single layer film having good adhesion on a gate insulating film or a substrate. There is.

  In order to achieve the above object, a metal single layer film forming method of the present invention is a method of forming a metal single layer film on the surface of a substrate, and before forming the metal single layer film, silane on the surface of the substrate. A coupling process is performed.

The wiring forming method according to the first aspect of the present invention for achieving the above object relates to a so-called lift-off method,
(A) forming a resist layer on a substrate from which a portion where wiring is to be formed is removed;
(B) a step of subjecting the exposed surface of the substrate to a silane coupling treatment;
(C) forming a metal single layer film on the resist layer and the substrate;
(D) removing the resist layer, thereby leaving a wiring made of a metal single layer film on the substrate;
It is characterized by comprising.

Further, the wiring forming method according to the second aspect of the present invention for achieving the above object relates to a so-called etching method,
(A) applying a silane coupling treatment to the surface of the substrate;
(B) forming a metal monolayer film on the surface of the substrate subjected to the silane coupling treatment;
(C) a step of selectively removing the metal single layer film by an etching method to form a wiring made of the metal single layer film on the substrate;
It is characterized by comprising.

In order to achieve the above object, a method of manufacturing a field effect transistor according to the first aspect of the present invention includes:
(A) forming a gate electrode on a support;
(B) forming a gate insulating film on the gate electrode;
(C) performing a silane coupling process on the surface of the gate insulating film;
(D) forming a source / drain electrode made of a metal single layer film on the gate insulating film subjected to the silane coupling treatment;
(E) forming a channel formation region made of a semiconductor material layer on the gate insulating film between the source / drain electrodes;
It is characterized by comprising.

In order to achieve the above object, a method of manufacturing a field effect transistor according to the second aspect of the present invention includes:
(A) applying a silane coupling treatment to the surface of the substrate;
(B) forming a source / drain electrode made of a metal single layer film on the surface of a silane coupling-treated substrate;
(C) forming a semiconductor material layer on the source / drain electrodes and the base material therebetween, and thereby obtaining a channel formation region composed of the semiconductor material layer between the source / drain electrodes;
(D) forming a gate insulating film on the semiconductor material layer;
(E) forming a gate electrode on the gate insulating film;
It is characterized by comprising.

The substrate in the metal single layer film forming method of the present invention, the substrate in the wiring forming method according to the first aspect or the second aspect of the present invention, and the substrate in the method of manufacturing the field effect transistor according to the second aspect of the present invention Furthermore, the gate insulating film in the method for manufacturing the field effect transistor according to the first aspect of the present invention can be subjected to silane coupling treatment if the outermost surface is terminated with an OH group. As long as it has a group, it may be composed of essentially any material. As an example, a SiO ₂ -based material can be mentioned. Furthermore, examples of the base and base material include organic insulating materials exemplified by polymethyl methacrylate (PMMA), polyvinyl phenol (PVP), polyvinyl alcohol (PVA), and polyethylene. In addition, as a material constituting the metal single layer film, for example, a metal that reacts with a thiol group (—SH), specifically, gold (Au), platinum (Pt), silver (Ag), palladium (Pd), rubidium. One type of metal selected from the group consisting of (Rb) and rhodium (Rh) can be exemplified.

Here, as the SiO ₂ material, silicon dioxide (SiO ₂ ), BPSG, PSG, BSG, AsSG, PbSG, silicon oxynitride (SiON), SOG (spin on glass), SiO ₂ material having a low dielectric constant (for example, , Polyaryl ether, cycloperfluorocarbon polymer and benzocyclobutene, cyclic fluororesin, polytetrafluoroethylene, fluorinated aryl ether, fluorinated polyimide, amorphous carbon, and organic SOG).

Physical vapor deposition method (PVD method, Physical Vapor Deposition method) exemplified by vacuum deposition method and sputtering method for bases and base materials or gate insulating films composed of SiO ₂ materials; Vapor phase growth method (CVD method); spin coating method; printing method such as screen printing method and ink jet printing method; various coating methods described later; dipping method (dipping method); casting method; spray method; SiO ₂ by thermal oxidation of silicon It can be formed by a known process such as forming.

Alternatively, the gate insulating film can be formed by oxidizing 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. Furthermore, for example, when a gate electrode is composed of Au, an insulating molecule having a functional group capable of forming a chemical bond with the gate electrode, such as a linear hydrocarbon modified at one end with a mercapto group. The gate insulating film can also be formed on the surface of the gate electrode by coating the surface of the gate electrode in a self-organizing manner by a method such as immersion.

The silane coupling agent can generally be represented by X—Si (OR) ₃ . Here, “X” means a functional group such as a thiol group (mercapto group), amino group, vinyl group, epoxy group, chloro group, methacryl group, and “OR” means a hydrolyzable group (for example, methoxy group). , An ethoxy group). Specific examples of the silane coupling agent include 3-mercaptopropyltrimethoxysilane [(CH ₃ O) ₃ SiC ₃ H ₃ SH].

  Various silane coupling treatment methods include exposing the substrate, base material or gate insulating film to the vapor of the silane coupling agent, dipping the silane coupling agent solution (dipping method), and various silane coupling agent solutions. The method of apply | coating by this coating method, the various printing methods, and the method of spin-coating a silane coupling agent solution can be mentioned. Here, as a coating 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 Examples thereof include a coater method, a slit orifice coater method, and a calendar coater method.

  As a constituent material of the gate electrode, one kind of metal selected from the group consisting of gold (Au), platinum (Pt), silver (Ag), palladium (Pd), rubidium (Rb) and rhodium (Rh) is illustrated. be able to. Alternatively, as a constituent material of the gate electrode, aluminum (Al), copper (Cu), nickel (Ni), chromium (Cr), tungsten (W), tantalum (Ta), titanium (Ti), indium ( Examples thereof include metals such as In) and tin (Sn), various alloys, or conductive particles made of these metals, or conductive particles of alloys containing these metals. A layered structure of layers containing can also be used. Furthermore, various conductive polymers (described later) such as poly (3,4-ethylenedioxythiophene) / polystyrene sulfonic acid [PEDOT / PSS] can be cited, and highly doped silicon can be cited. You can also.

  As a method for forming a metal monolayer film, source / drain electrodes, and gate electrodes, depending on the materials constituting them, PVD methods exemplified by vacuum deposition methods and sputtering methods; various CVD methods including MOCVD methods; spins Coating method; printing method such as screen printing method and ink jet printing method using conductive paste and various conductive polymer solutions described later; various coating methods described above; lift-off method; shadow mask method; electroplating method and electroless method Any one of a plating method such as a plating method or a combination thereof; and a spray method, or a combination with a patterning technique as necessary may be mentioned. In addition, as the 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, direct current sputtering method, direct current magnetron sputtering method Various sputtering methods such as high-frequency sputtering method, magnetron sputtering method, ion beam sputtering method, bias sputtering method, (d) DC (direct current) method, RF method, multi-cathode method, activation reaction method, electric field evaporation method, high-frequency method Various ion plating methods such as an ion plating method and a reactive ion plating method can be given.

As a material constituting the semiconductor material layer, 2,3,6,7-dibenzoanthracene (also called pentacene); C ₉ S ₉ (benzo [1,2-c; 3,4-c ′; 5,6-c) "] tris [1,2] dithiol-1,4,7 _{trithiones); C 24 H 14 S 6} ( alpha - sexithiophene); fullerene (C _60);; phthalocyanines typified by copper phthalocyanine tetrathiotetracene (C ₁₈ H ₈ S ₄ ); tetraselenotetracene (C ₁₈ H ₈ Se ₄ ); tetratellurtetracene (C ₁₈ H ₈ Te ₄ ); poly (3,4-ethylenedioxythiophene) / polystyrene sulfonic acid [PEDOT The structural formula (1) of poly (3,4-ethylenedioxythiophene) and the structural formula (2) of polystyrene sulfonic acid are shown in FIG.

Alternatively, as a material constituting the semiconductor material layer, for example, a heterocyclic conjugated conductive polymer and a heteroatom-containing conjugated conductive polymer exemplified below can be used. In the structural formula, “R” and “R ′” mean an alkyl group (C _n H _{2n + 1} ).

[Heterocyclic conjugated conductive polymer]
Polypyrrole [see structural formula (3) in FIG. 6]
Polyfuran [see structural formula (4) in FIG. 6]
Polythiophene [see structural formula (5) in FIG. 6]
Polyselenophene [see structural formula (6) in FIG. 6]
Polytellophene [see structural formula (7) in FIG. 6]
Poly (3-alkylthiophene) [see structural formula (8) in FIG. 6]
Poly (3-thiophene-β-ethanesulfonic acid) [see structural formula (9) in FIG. 6]
Poly (N-alkylpyrrole) [see structural formula (10) in FIG. 7]
Poly (3-alkylpyrrole) [see structural formula (11) in FIG. 7]
Poly (3,4-dialkylpyrrole) [see structural formula (12) in FIG. 7]
Poly (2,2′-thienylpyrrole) [see structural formula (13) in FIG. 7]

[Containing heteroatom-containing conductive polymer]
Polyaniline [see structural formula (14) in FIG. 7]
Poly (dibenzothiophene sulfide) [see structural formula (15) in FIG. 7]

Alternatively, as a material constituting the semiconductor material layer, an organic semiconductor molecule having a conjugated bond, a thiol group (SH), an amino group (—NH ₂ ), an isocyano group (—NC), thioacetoxy at both ends of the molecule. The following materials can be exemplified as the organic semiconductor molecule. More specifically, the organic semiconductor molecule can be exemplified by those having a thio group (—SCOCH ₃ ) or a carboxyl group (—COOH).

4,4′-biphenyldithiol [see the structural formula (16) in FIG. 8]
4,4′-Diisocyanobiphenyl [see the structural formula (17) in FIG. 8]
4,4′-Diisocyano-p-terphenyl [see structural formula (18) in FIG. 8]
2,5-bis (5′-thioacetoxyl-2′-thiophenyl) thiophene [see the structural formula (19) in FIG. 8]

  Furthermore, the semiconductor material layer can be made of an inorganic semiconductor material, and specific examples of the inorganic semiconductor material include Si, Ge, and Se.

  When the semiconductor material layer is composed of the above-described conductive polymer material, the method for forming the semiconductor material layer (channel formation region) is exemplified by a vacuum deposition method or a sputtering method, although it depends on the material constituting the semiconductor material layer. Various PVD methods; Various CVD methods; Spin coating methods; Printing methods such as screen printing methods and inkjet printing methods; Various coating methods described above; Immersion method (dipping method); Stamp method; Lift-off method; Shadow mask method; Any of the spray methods can be mentioned. In the case where the semiconductor material layer is composed of the above-described inorganic semiconductor material, various CVD methods and PVD methods can be used as a method for forming the semiconductor material layer (channel formation region).

  The field effect transistor manufactured by the method for manufacturing a field effect transistor according to the first aspect of the present invention is formed on a support, and as the support, various glass substrates and an insulating layer on the surface are used. Examples thereof include various formed glass substrates, quartz substrates, quartz substrates having an insulating layer formed on the surface, and silicon substrates having an insulating layer formed on the surface. Furthermore, as a support, a plastic film or a plastic sheet composed of a polymer material exemplified by polyethersulfone (PES), polyimide, polycarbonate, polyethylene terephthalate (PET), or a plastic substrate can be mentioned. 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. Further, the field effect transistor may be sealed with resin. Also in the field effect transistor manufactured by the method for manufacturing a field effect transistor according to the second aspect of the present invention, the substrate is preferably supported by a support, and the above-mentioned materials are mentioned as the support. be able to.

  According to the present invention, the surface of the base body, the base material, and the gate insulating film is subjected to silane coupling treatment, so that the outermost surface of the base body, the base material, and the gate insulating film is terminated with a functional group such as a thiol group. Next, if a metal single layer film is formed on the substrate, base material, or gate insulating film, the functional group can increase the adhesion between the base material, base material, gate insulating film and metal single layer film. Serves as a function. And since a metal single layer film can be formed on a substrate, a base material, or a gate insulating film, it improves etching control, reduces raw material costs, simplifies the manufacturing process of field effect transistors, etc., and reduces manufacturing costs. Can be achieved. Further, by constituting the source / drain electrodes of the field effect transistor from a metal single layer film, there is no movement of electric charge between the adhesion layer and the channel, and the source / drain electrodes made of the metal single layer film and the channel The electric charge can be smoothly transferred between them, and the improvement of the characteristics of the field effect transistor such as the improvement of the channel mobility can be achieved.

1A to 1D are schematic partial cross-sectional views of a support and the like for explaining the method for manufacturing the field-effect transistor of Example 1. FIG. 2A to 2C are schematic partial cross-sectional views of a support and the like for explaining the method for manufacturing the field-effect transistor of Example 1 following FIG. 1D. . FIG. 3 is a schematic partial cross-sectional view of a support and the like for explaining the method for manufacturing the field effect transistor of Example 1 following FIG. 4A to 4D are schematic partial cross-sectional views of a support and the like for explaining the method for producing the field effect transistor of Example 2. FIG. FIG. 5 is a schematic partial cross-sectional view of a support and the like for explaining the manufacturing method of the field effect transistor of Example 2 following FIG. FIG. 6 illustrates a structural formula of a conductive polymer material constituting a semiconductor material layer suitable for use in the present invention. FIG. 7 illustrates a structural formula of a conductive polymer material constituting a semiconductor material layer suitable for use in the present invention. FIG. 8 illustrates a structural formula of a conductive polymer material constituting a semiconductor material layer suitable for use in the present invention.

  In the following, the present invention will be described based on examples with reference to the drawings, but without any change in the configuration of the conventional field effect transistor and the configuration of the wiring, the manufacturing process is slightly added, thereby improving the adhesion. Excellent source / drain electrodes and wirings can be obtained.

  Example 1 is a method for manufacturing a field-effect transistor according to the first aspect of the present invention, a wiring formation method according to the first and second aspects of the present invention, and formation of a metal single layer film according to the present invention. Regarding the method. Schematic view when a field effect transistor (more specifically, a thin film transistor, TFT) obtained by the field effect transistor manufacturing method of Example 1 is cut on a virtual vertical plane perpendicular to the extending direction of the gate electrode. A partial cross-sectional view is shown in FIG.

The field effect transistor in Example 1 is specifically a so-called bottom gate type and bottom contact type TFT,
(A) a gate electrode 12 formed on a support;
(B) a gate insulating film 13 formed on the gate electrode 12;
(C) a source / drain electrode 14 formed on the gate insulating film 13, and
(D) a channel forming region 15 made of a semiconductor material layer formed between the source / drain electrodes 14 and on the gate insulating film 13;
It has.

Furthermore, an interlayer insulating layer 20 made of SiO ₂ is formed on the entire surface, and wirings 21 are formed on the interlayer insulating layer 20. In addition, an opening is formed in the portion of the interlayer insulating layer 20 above the word line and the source / drain electrode 14 extending from the gate electrode 12, and a wiring 21 extends into these openings, and the word line and The source / drain electrode 14 is connected.

  Here, the TFT shown in FIG. 3 is manufactured not only by the field effect transistor manufacturing method according to the first aspect of the present invention, but also by considering the gate electrode 12 functioning as a word line as a wiring. 12 (wiring) is formed by the wiring forming method according to the first aspect of the present invention, and the wiring 21 on the interlayer insulating layer 20 is formed by the wiring forming method according to the second aspect of the present invention.

In Example 1, pentacene was used as the semiconductor material layer constituting the channel formation region 15. The support was composed of a glass substrate 10 on the surface of which an insulating layer 11 made of SiO ₂ was formed by sputtering. Further, the gate electrode 12, the source / drain electrode 14, and the wiring 21 are made of a metal single layer film made of gold (Au), and the gate insulating film 13 is made of SiO ₂ . Further, the interlayer insulating layer 20 is made of SiO ₂ . That is, the insulating layer 11 corresponds to the substrate in the wiring forming method according to the first aspect of the present invention, and the interlayer insulating layer 20 corresponds to the substrate in the wiring forming method according to the second aspect of the present invention. The layer 11, the gate insulating film 13 or the interlayer insulating layer 20 corresponds to the substrate in the metal single layer film forming method of the present invention.

  Hereinafter, with reference to FIGS. 1A to 1D, FIGS. 2A to 2C, and FIG. An outline of a method for manufacturing a field effect transistor will be described.

[Step-100]
First, the gate electrode 12 is formed on the support. Specifically, a resist layer 31 in which a portion where a wiring (gate electrode 12) is to be formed is removed from the insulating layer 11 (base body) made of SiO ₂ formed on the surface of the glass substrate 10 by lithography. It forms based on (refer (A) of FIG. 1). In addition, after the formation of the resist layer 31, it is preferable to perform an ashing process using oxygen plasma in order to remove the residue of the resist layer.

Then, 3-mercaptopropyl trimethoxysilane _{[(CH 3 O) 3 SiC} 3 H 3 SH] solution (solvent: ethanol) was exposed to vapor of, and dried, the surface of the exposed substrate (insulating layer 11) Silane coupling treatment can be performed.

  Next, a metal single layer film made of gold (Au) is formed on the resist layer 31 and the base body (insulating layer 11) by a vacuum deposition method, so that gold (Au) is formed as shown in FIG. A gate electrode 12 composed of a metal single-layer film made of can be obtained. Thereafter, the resist layer 31 is removed by a lift-off method, so that the wiring (gate electrode 12) made of a metal single layer film is left on the substrate (insulating layer 11). Thus, the gate electrode 12 corresponding to the wiring can be formed over the base body (insulating layer 11) (see FIG. 1C).

  By performing the above [Step-100], the metal single layer film forming method of the present invention and the wiring forming method according to the first aspect of the present invention are carried out.

[Step-110]
Next, the gate insulating film 13 is formed on the support (more specifically, the insulating layer 11) including the gate electrode 12. Specifically, the gate insulating film 13 made of SiO ₂ is formed on the gate electrode 12 and the insulating layer 11 based on the sputtering method. When forming the gate insulating film 13, by covering a part of the gate electrode 12 with a hard mask, an extraction portion (not shown) of the gate electrode 12 can be formed without a photolithography process.

[Step-120]
Next, after the surface of the gate insulating film 13 is subjected to silane coupling treatment, the source / drain electrodes formed of a metal single layer film made of gold (Au) are formed on the gate insulating film 13 subjected to the silane coupling treatment. 14 is formed.

  Specifically, a resist layer 32 from which portions where the source / drain electrodes 14 are to be formed is removed is formed on the gate insulating film 13 based on the lithography technique (see FIG. 1D). In addition, after the formation of the resist layer 32, it is preferable to perform an ashing process using oxygen plasma in order to remove the residue of the resist layer. Then, in the same manner as in [Step-100], the exposed surface of the gate insulating film 13 is subjected to silane coupling treatment. Next, a metal single layer film made of gold (Au) is formed on the resist layer 32 and the gate insulating film 13 by a vacuum deposition method, so that gold (Au) is formed as shown in FIG. A source / drain electrode 14 composed of a metal single layer film made of can be obtained. Thereafter, the resist layer 32 is removed by a lift-off method, so that the source / drain electrodes 14 made of a metal single layer film are left on the gate insulating film 13. Thus, the source / drain electrode 14 can be formed on the gate insulating film 13 (see FIG. 2B).

[Step-130]
Next, a channel formation region 15 made of a semiconductor material layer is formed on the gate insulating film 13 between the source / drain electrodes 14 (see FIG. 2C). Specifically, an organic semiconductor material layer made of pentacene is formed on the source / drain electrode 14 and the gate insulating film 13 based on a vacuum deposition method. When forming the organic semiconductor material layer, the channel formation region 15 can be formed without a photolithography process by covering a part of the gate insulating film 13 and the source / drain electrode 14 with a hard mask.

  Through the execution of the above [Step-100] to [Step-140], the manufacturing method of the field effect transistor according to the first aspect of the present invention and the metal single layer film forming method of the present invention were implemented. become.

[Step-140]
Next, after an interlayer insulating layer 20 made of SiO ₂ is formed on the entire surface, an opening is formed in the portion of the interlayer insulating layer 20 above the word line and the source / drain electrode 14 extending from the gate electrode 12.

  Then, the surface of the interlayer insulating layer 20 (corresponding to the substrate) is subjected to silane coupling treatment in the same manner as in [Step-100] of Example 1.

  Next, a metal single layer film is formed on the surface of the substrate (interlayer insulating layer 20) subjected to the silane coupling treatment. Specifically, a metal single layer film made of gold (Au) is formed on the interlayer insulating layer 20 including the inside of these openings by a vacuum deposition method, and this metal single layer film is selectively formed by an etching method. By removing (that is, by patterning) the wiring (not shown) connected to the word line extending from the gate electrode 12 and the source / drain electrode 14 on the interlayer insulating layer 20 as the base. The wiring 21 connected to can be formed (FIG. 3). Thus, the TFT of Example 1 can be obtained.

  By performing this [Step-140], the wiring forming method according to the second aspect of the present invention and the metal single layer film forming method of the present invention are implemented.

When the channel mobility of the TFT thus obtained was measured, a result of 2.0 × 10 ⁻¹ cm ² / (V · second) was obtained. On the other hand, instead of [Step-120], a titanium (Ti) layer is formed as an adhesion layer, and then a TFT having a source / drain electrode made of gold (Au) is manufactured as a comparative example, and the channel mobility is increased. As a result of measurement, only a result of 7.1 × 10 ⁻³ cm ² / (V · sec) was obtained. That is, it was found that the TFT manufactured by the method of the present invention has a channel mobility improved by two orders of magnitude as compared with the comparative TFT manufactured by the conventional method. Further, no phenomenon such as peeling of the source / drain electrode 14, the gate electrode 12, and the wiring 21 was observed.

  Example 2 is a method for manufacturing a field effect transistor according to the second aspect of the present invention, a wiring formation method according to the first and second aspects of the present invention, and formation of a metal single layer film according to the present invention. Regarding the method. A schematic partial view of a field-effect transistor (more specifically, a TFT) obtained by cutting the field-effect transistor of Example 2 on a virtual vertical plane perpendicular to the extending direction of the gate electrode. A cross-sectional view is shown in FIG.

The field effect transistor in Example 2 is a so-called bottom gate type and top contact type TFT,
(A) source / drain electrodes 14 formed on the substrate;
(B) a channel forming region 15 made of a semiconductor material layer, which is formed between the source / drain electrodes 14 and on the base material (more specifically, the insulating layer 111);
(C) a gate insulating film 13 formed on the semiconductor material layer, and
(D) a gate electrode 12 formed on the gate insulating film 13,
It has.

Furthermore, an interlayer insulating layer 20 made of SiO ₂ is formed on the entire surface, and wirings 21 are formed on the interlayer insulating layer 20. In addition, an opening is formed in the portion of the interlayer insulating layer 20 above the word line and the source / drain electrode 14 extending from the gate electrode 12, and a wiring 21 extends into these openings, and the word line and The source / drain electrode 14 is connected.

  Here, not only the TFT shown in FIG. 5 is manufactured by the field effect transistor manufacturing method according to the second aspect of the present invention, but also the gate electrode 12 functioning as a word line is regarded as a wiring. 12 (wiring) is formed by the wiring forming method according to the first aspect of the present invention, and the wiring 21 on the interlayer insulating layer 20 is formed by the wiring forming method according to the second aspect of the present invention.

Also in Example 2, the same semiconductor material layer as in Example 1 was used as the semiconductor material layer constituting the channel formation region 15. The base material was an insulating layer 111 made of SiO ₂ . The insulating layer 111 is formed on the surface of the glass substrate 10 as a support by a sputtering method. Further, the gate electrode 12, the source / drain electrode 14, and the wiring 21 are made of a metal single layer film made of gold (Au), and the gate insulating film 13 is made of SiO ₂ . Further, the interlayer insulating layer 20 is made of SiO ₂ . That is, the gate insulating film 13 corresponds to the substrate in the wiring forming method according to the first aspect of the present invention, and the interlayer insulating layer 20 corresponds to the substrate in the wiring forming method according to the second aspect of the present invention. The insulating layer 111, the gate insulating film 13 or the interlayer insulating layer 20 corresponds to the substrate in the metal single layer film forming method of the present invention.

  Hereinafter, with reference to FIGS. 4A to 4D which are schematic partial cross-sectional views of a support and the like, and FIG. 5, an outline of a method for manufacturing the field effect transistor of Example 2 will be described. To do.

[Step-200]
First, the surface of the base material is subjected to silane coupling treatment, and then a source / drain electrode made of a metal single layer film is formed on the surface of the base material subjected to silane coupling treatment. Specifically, in the same manner as in [Step-120] in Example 1, the resist layer 131 from which the portion where the source / drain electrode 14 is to be formed is removed on the insulating layer 111 made of SiO _{2 as the} base material. Is formed based on the lithography technique (see FIG. 4A). Note that after the formation of the resist layer 131, it is preferable to perform an ashing process using oxygen plasma in order to remove residues of the resist layer. Then, in the same manner as in [Step-100] of Example 1, the exposed surface of the insulating layer 111 is subjected to silane coupling treatment. Next, a metal single layer film made of gold (Au) is formed on the resist layer 131 and the base material (insulating layer 111) by a vacuum vapor deposition method, as shown in FIG. A source / drain electrode 14 composed of a metal single layer film made of (Au) can be obtained. Thereafter, the resist layer 131 is removed by a lift-off method, so that the source / drain electrodes 14 made of a metal single layer film are left on the base material (insulating layer 111). In this way, the source / drain electrode 14 can be formed on the base material (insulating layer 111) (see FIG. 4C).

[Step-210]
Next, a semiconductor material layer is formed on the source / drain electrode 14 and the base material (insulating layer 111) therebetween, and thus the semiconductor material layer is formed on the base material (insulating layer 111) between the source / drain electrodes 14. A channel forming region 15 is obtained. Specifically, in the same manner as in [Step-130] of Example 1, the same organic semiconductor material layer as used in Example 1 is formed on the source / drain electrode 14 and the insulating layer 11 based on the vacuum deposition method. Form.

[Step-220]
Thereafter, a gate insulating film 13 is formed on the semiconductor material layer. Specifically, the gate insulating film 13 made of SiO _{2 is} formed on the entire surface based on the sputtering method in the same manner as in [Step-110] of the first embodiment.

[Step-230]
Next, the gate electrode 12 is formed on the gate insulating film 13. Specifically, in the same manner as in [Step-100] of Example 1, the portion where the gate electrode (corresponding to 12 wirings) is to be formed on the gate insulating film 13 (corresponding to the substrate) was removed. A resist layer (not shown) is formed based on a lithography technique. Note that after the formation of the resist layer, it is preferable to perform an ashing process using oxygen plasma in order to remove the residue of the resist layer.

  Then, in the same manner as in [Step-100] in Example 1, the exposed surface of the substrate (gate insulating film 13) is subjected to silane coupling treatment.

  Next, a metal single layer film made of gold (Au) is formed on the resist layer and the base body (gate insulating film 13) by a vacuum deposition method, thereby forming a metal single layer film made of gold (Au). The gate electrode 12 can be obtained. Thereafter, the resist layer is removed by a lift-off method, so that the wiring (gate electrode 12) made of a metal single layer film is left on the base (gate insulating film 13). Thus, the gate electrode 12 corresponding to the wiring can be formed on the gate insulating film 13 which is a base (see FIG. 4D).

  Through the execution of the above [Step-200] to [Step-230], the field effect transistor manufacturing method according to the second aspect of the present invention and the metal single layer film forming method of the present invention were implemented. become. In addition, by performing [Step-230], the wiring forming method according to the first aspect of the present invention and the metal single layer film forming method of the present invention are implemented.

[Step-240]
Next, in the same manner as in [Step-140] of Example 1, an interlayer insulating layer 20 made of SiO ₂ is formed on the entire surface, and then the word line extending from the gate electrode 12 and the interlayer above the source / drain electrode 14 are formed. An opening is formed in the insulating layer 20. Then, the surface of the interlayer insulating layer 20 (corresponding to the base) is subjected to silane coupling treatment in the same manner as in [Step-100] of Example 1. Next, a metal single layer film is formed on the surface of the substrate subjected to the silane coupling treatment. Specifically, a metal single layer film made of gold (Au) is formed on the interlayer insulating layer 20 including the inside of these openings by a vacuum deposition method, and this metal single layer film is selectively formed by an etching method. By removing (that is, by patterning) the wiring (not shown) connected to the word line extending from the gate electrode 12 and the source / drain electrode 14 on the interlayer insulating layer 20 as the base. The wiring 21 connected to can be formed (FIG. 5). Thus, the TFT of Example 2 can be obtained. In the obtained TFT, no phenomenon such as peeling of the source / drain electrode 14, the gate electrode 12, and the wiring 21 was observed.

  By performing this [Step-240], the wiring forming method according to the second aspect of the present invention and the metal single layer film forming method of the present invention are carried out.

  As mentioned above, although this invention was demonstrated based on the preferable Example, this invention is not limited to these Examples. The structure and manufacturing conditions of the field effect transistor are illustrative and can be changed as appropriate. In Example 1 and Example 2, the gate electrode (wiring) may be formed by the wiring forming method according to the second aspect of the present invention, and the wiring 21 on the interlayer insulating layer 20 is formed according to the first aspect of the present invention. You may form by the wiring formation method which concerns on the aspect. The wiring structure obtained by the wiring forming method of the present invention is not limited to the wiring structure described in the embodiments. In addition, 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. Each TFT may be cut and individualized and used as a discrete component.

DESCRIPTION OF SYMBOLS 10 ... Glass substrate, 11, 111 ... Insulating layer, 12 ... Gate electrode, 13 ... Gate insulating film, 14 ... Source / drain electrode, 15 ... Channel formation area, 20 * ..Interlayer insulating layer, 21 ... wiring, 31, 32, 131 ... resist layer
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Claims (12)

(A) applying a silane coupling treatment to the surface of the substrate;
(B) forming a gate electrode on the silane-coupled substrate;
(C) forming a gate insulating film on the gate electrode;
(D) performing a silane coupling process on the surface of the gate insulating film;
(E) forming a source / drain electrode made of a metal single layer film on the gate insulating film subjected to the silane coupling treatment;
(F) forming a channel formation region made of a semiconductor material layer on the gate insulating film between the source / drain electrodes;
A method of manufacturing a field effect transistor comprising:   2. The method of manufacturing a field effect transistor according to claim 1, wherein the gate insulating film is made of a material whose outermost surface is terminated with an OH group.   3. The method of manufacturing a field effect transistor according to claim 1, wherein the substrate is made of a material whose outermost surface is terminated with an OH group.   The method of manufacturing a field effect transistor according to any one of claims 1 to 3, wherein the gate electrode is made of a metal single layer film.   5. The method of manufacturing a field effect transistor according to claim 4, wherein the gate electrode and the source / drain electrode are made of the same type of metal.   The silane coupling agent used for the silane coupling treatment in the step (A) and the silane coupling agent used for the silane coupling treatment in the step (D) are the same kind of silane coupling agents. The method for producing a field effect transistor according to claim 5. (A) applying a silane coupling treatment to the surface of the substrate;
(B) forming a source / drain electrode made of a metal single layer film on the surface of the substrate subjected to the silane coupling treatment;
(C) forming a semiconductor material layer on the source / drain electrodes and the base material therebetween, thereby obtaining a channel formation region composed of the semiconductor material layers between the source / drain electrodes;
(D) forming a gate insulating film on the semiconductor material layer;
(E) performing a silane coupling process on the surface of the gate insulating film;
(F) forming a gate electrode on the gate insulating film subjected to the silane coupling treatment;
A method of manufacturing a field effect transistor comprising:   8. The method of manufacturing a field effect transistor according to claim 7, wherein the base material is made of a material whose outermost surface is terminated with an OH group.   9. The method of manufacturing a field effect transistor according to claim 7, wherein the gate insulating film is made of a material whose outermost surface is terminated with an OH group.   10. The method of manufacturing a field effect transistor according to claim 7, wherein the gate electrode is made of a metal single layer film.   11. The method of manufacturing a field effect transistor according to claim 10, wherein the gate electrode and the source / drain electrode are made of the same type of metal.   The silane coupling agent used for the silane coupling treatment in the step (A) and the silane coupling agent used for the silane coupling treatment in the step (E) are the same kind of silane coupling agents. The method for manufacturing a field effect transistor according to claim 11.

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