JP2005268550A - Organic semiconductor, semiconductor device using the same, and method of manufacturing the same - Google Patents

Organic semiconductor, semiconductor device using the same, and method of manufacturing the same Download PDF

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JP2005268550A
JP2005268550A JP2004079094A JP2004079094A JP2005268550A JP 2005268550 A JP2005268550 A JP 2005268550A JP 2004079094 A JP2004079094 A JP 2004079094A JP 2004079094 A JP2004079094 A JP 2004079094A JP 2005268550 A JP2005268550 A JP 2005268550A
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organic semiconductor
material
effect transistor
field effect
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Yasuhiko Hayashi
靖彦 林
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Japan Science & Technology Agency
独立行政法人科学技術振興機構
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B82NANOTECHNOLOGY
    • B82YSPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y30/00Nanotechnology for materials or surface science, e.g. nanocomposites
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B82NANOTECHNOLOGY
    • B82YSPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y10/00Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic thin film of a polymeric material system which can be constituted at a low cost, can be constituted as a p-type film, and can be constituted as an n-type film because of its simple structure, and which is excellent in current-driving power; to provide a semiconductor device using the same; and the method of manufacturing the same. <P>SOLUTION: A field-effect transistor 10 comprises an organic semiconductor layer 16 used as a channel formed on a substrate 11. The organic semiconductor layer 16 comprises the mixture of a first material of the derivative of polyphenylene vinylene or a polythiophene system polymeric material and a second material of at least one of C<SB>n</SB>fullerene (in which n is an integer equal to or more than 60), a C<SB>n</SB>fullerene derivative, CNTs (carbon nanotubes) having a semiconductor nature, and a CNTs compound. The organic semiconductor layer 16 can be manufactured using the method of application and deposition. Further, the type of the conductivity thereof can be controlled. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an organic semiconductor using a polymer material, a semiconductor device using the organic semiconductor, and a manufacturing method thereof.

  Conventionally, a field effect transistor using a polymer-based organic thin film, for example, an oxide film formed on the surface of a Si substrate, or a polymer material is applied, for example, onto a flexible substrate such as PET on which an oxide film is deposited in advance. The film is formed by simple ink-jet printing or printing by a rotary press.

By the way, a field effect transistor using such an organic thin film of a polymer material is often a p-type field effect transistor.
In contrast, in order to constitute the n-type field effect transistor, as a polymer material, although the use of C n fullerene or its derivatives have been studied, the formation of the these materials on a substrate As a method for this, for example, a vacuum deposition method is used, so that it is difficult to manufacture a field effect transistor by a simple coating film formation as in the case of a conventional polymer material system.
In addition, since these materials are unstable in the atmosphere, it is necessary to be shielded from the atmosphere by a sealing film after the film formation, which increases the number of processes.
Therefore, for example, in order to reduce power consumption, it has been impossible to configure a so-called complementary integrated circuit in which p-type and n-type are mixed.

In addition, in order to increase the carrier mobility in the field effect transistor, research for shortening the channel length and increasing the current driving capability has been widely performed.
Although it is possible to increase the current driving capability and switching speed by increasing the carrier mobility, the current driving capability of the field effect transistor using the high molecular material is lower than that using the low molecular material. .
In the conventional LSI process, elements are formed using a photolithography method during or after the film formation. However, when a photolithography method is used after the formation of the polymer film, the properties of the polymer deteriorate due to the temperature process required for the film and the influence of ultraviolet rays used for exposure, and therefore it cannot be introduced.
Therefore, a polymer material is formed by simple ink jet printing by the above-described coating film formation or printing by a rotary press. However, in such a method, a very fine structure of several microns to submicron order is formed. It is difficult to manufacture, and therefore it is difficult to shorten the channel length with high accuracy.

On the other hand, in Patent Document 1, a C n compound (n is an integer of 60 or more) and a π-conjugated compound different from C n are deposited by vapor deposition in a stacked or mixed state. A field effect transistor is disclosed.
In Patent Document 2, an n-type field effect transistor in which a thin fullerene (for example, C 60 ) is deposited as a semiconductor layer on a substrate by vapor deposition in an ultrahigh vacuum and then sealed with a protective film is disclosed. It is disclosed.

Japanese Patent Application Laid-Open No. 06-273711 JP 08-264863 A

However, in the field effect transistor in Patent Document 1, in the case of laminating each depositing a C n compound and π-conjugated compound, the number of steps increases, since the film formation is performed by each vacuum evaporation There is a problem that the cost becomes high.
Also, C n compound and π-conjugated compound is evaporated at the same time, when depositing a mixed state, heat by end up with different physical properties of the π-conjugated compound during deposition, resulting excellent field effect transistor There is a problem that it is not possible.

  In addition, the field effect transistor disclosed in Patent Document 2 requires a vapor deposition process in an ultra-high vacuum, and there is a problem that the manufacturing cost increases.

  Furthermore, in the above-mentioned Patent Document 1 and Patent Document 2, both an n-type semiconductor layer and a field effect transistor are manufactured, and a so-called complementary integrated circuit composed of p-type and n-type is realized. There is a problem that is not.

  In view of the above, the present invention is a high-molecular-weight organic semiconductor that can be configured as a p-type or an n-type at a low cost with a simple configuration, and further enhances the current driving capability. It is an object of the present invention to provide a used semiconductor device and a manufacturing method thereof.

To achieve the above object, the organic semiconductor of the present invention comprises a first material comprising a polyphenylene vinylene derivative or a polythiophene polymer material, C n fullerene (where n is an integer of 60 or more), C n fullerene. It is composed of a mixture of a derivative, semiconducting CNTs (carbon nanotubes), and a second material made of at least one of CNTs compounds.
In the above configuration, preferably, the mixture weight ratio x of the first material and the second material is set to x> 1.1 to 1.5 so that the conductivity type of the organic semiconductor is set to p-type, and x By setting <1.1 to 1.5, the conductivity type of the organic semiconductor is set to n-type.

  According to the above configuration, the p-type and n-type semiconductors can be obtained by mixing the first material and the second material. And the semiconductor manufactured in this way is stable in air | atmosphere, and can make carrier mobility high.

Furthermore, the field effect transistor of the present invention includes an organic semiconductor layer serving as a channel formed on a substrate, and the organic semiconductor layer includes a first material made of a polyphenylene vinylene derivative or a polythiophene polymer material, and C n fullerene (where, n represents 60 or more integer), wherein C n fullerene derivative, CNTs having semiconducting (carbon nanotubes), and a second material consisting of at least one of CNTs compound that consists of a mixture of And In the above configuration, preferably, the mixture weight ratio x of the first material and the second material is set to x> 1.1 to 1.5 so that the conductivity type of the organic semiconductor is set to p-type, and x By setting <1.1 to 1.5, the conductivity type of the organic semiconductor is set to n-type.
The organic semiconductor layer is preferably formed on the substrate by a coating film forming method. Further, at least a part of the organic semiconductor layer is preferably irradiated with light for a predetermined time in a vacuum or in a predetermined gas atmosphere, so that the mutual conductance of the field effect transistor can be increased.

According to the above configuration, in particular, a polymer material-based n-type field effect transistor that has been conventionally difficult to obtain by the coating film forming method can be easily realized by the coating film forming method.
Accordingly, the number of processes can be reduced because the conventional laminating process is not required, and the first material and the second material are stable in the air. For example, the vacuum deposition method is not used. In addition, it is possible to form a film in the atmosphere, and it is not necessary to hermetically seal with a protective film after the film formation. Accordingly, a field effect transistor using a polymer material-based organic thin film can be easily configured with a simple configuration at low cost and in a short time without changing the physical properties of the first material and the second material. be able to.
Furthermore, since the semiconductor layer described above has high carrier mobility, a field effect transistor with high current driving capability and high switching speed can be obtained. Then, by performing light irradiation treatment to the field effect transistor, it can be increased and the g m.

In addition, the optical field effect transistor of the present invention includes an organic semiconductor layer serving as a channel formed on a substrate, and the organic semiconductor layer includes a first material made of a polyphenylene vinylene derivative or a polythiophene polymer material, and C It consists of a mixture of n fullerene (where n is an integer of 60 or more), C n fullerene derivatives, semiconducting CNTs (carbon nanotubes), and a second material composed of at least one of CNTs compounds, and is organic The current between the drain and the source of the optical field effect transistor changes in accordance with light irradiation to the semiconductor layer.
In the above configuration, preferably, the mixture weight ratio x of the first material and the second material is set to x> 1.1 to 1.5 so that the conductivity type of the organic semiconductor is set to p-type, and x By setting <1.1 to 1.5, the conductivity type of the organic semiconductor is set to n-type.

  According to the above configuration, an n-type or p-type optical field effect transistor with high photosensitivity can be realized.

The integrated circuit of the present invention includes an organic semiconductor layer formed on a substrate, and the organic semiconductor layer includes a first material made of a polyphenylene vinylene derivative or a polythiophene polymer material, and a C n fullerene (here, , n represents more than 60 integer), C n fullerene derivative, CNTs (carbon nanotubes) having semiconducting, characterized and a second material consisting of at least one of CNTs compound that consists of a mixture of.
In the above configuration, preferably, the mixture weight ratio x of the first material and the second material is set to x> 1.1 to 1.5 so that the conductivity type of the organic semiconductor is set to p-type, and x By setting <1.1 to 1.5, the conductivity type of the organic semiconductor is set to n-type.
The integrated circuit preferably includes a complementary inverter including a p-type field effect transistor in which the conductivity type of the organic semiconductor layer is p-type and an n-type field effect transistor in which the conductivity type of the organic semiconductor layer is n-type. A complementary integrated circuit.

  According to the above configuration, an integrated circuit made of an n-type field effect transistor made of an organic semiconductor layer, which has been difficult to obtain in the past, can be realized. A complementary integrated circuit can be easily realized by combining an n-type field effect transistor and a p-type field effect transistor.

In addition, a method for manufacturing a semiconductor device according to the present invention includes a first material made of a polyphenylene vinylene derivative or a polythiophene polymer material, a C n fullerene (where n is an integer of 60 or more), a C n fullerene derivative, A semiconducting CNTs (carbon nanotube) and a second material composed of at least one of CNTs compounds are mixed, and this mixture is applied onto a substrate by a coating film forming method to form an organic semiconductor layer. A film forming step is included.
In the above structure, the semiconductor device having an organic semiconductor layer is preferably any one of a field effect transistor, an optical field effect transistor, an integrated circuit, and a complementary integrated circuit.
Preferably, the mixture weight ratio x of the first material and the second material is set to x> 1.1 to 1.5 to set the conductivity type of the organic semiconductor to p-type, and x <1 .1 to 1.5, the conductivity type of the organic semiconductor is set to n-type.

  According to the above configuration, p-type and n-type field effect transistors using an organic semiconductor layer and an integrated circuit using the same can be manufactured easily and at low cost by a coating film forming method. Thereby, for example, a p-type and an n-type semiconductor layer can be simultaneously formed on a substrate, and for example, a complementary integrated circuit can be easily configured.

  In the above configuration, more preferably, the organic semiconductor layer includes a light irradiation process in which light irradiation is performed for a predetermined time in a vacuum or in a predetermined gas atmosphere. Preferably, the characteristics of the field effect transistor included in the semiconductor device are adjusted by irradiating the organic semiconductor layer with light.

  According to the above configuration, the mobility of the semiconductor layer is improved by this light irradiation treatment, so that the current driving capability of the field effect transistor can be improved regardless of the shortening of the channel. As a result, various semiconductor devices having high current drive capability can be manufactured at low cost by a coating film forming method using a spin casting method or a printing process method without using a photolithography method necessary for shortening the channel. .

  According to the present invention, an organic semiconductor thin film of a polymer material system that can be configured as a p-type or an n-type can be obtained by a coating film formation method at a low cost with a simple configuration. In addition, a semiconductor device having a large current driving capability using the organic semiconductor and a manufacturing method thereof are provided.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
First, a polymer material-based organic thin film according to the first embodiment of the present invention will be described.
Semiconductor composed of an organic thin film of polymer material system of the present invention, polyphenylene vinylene (Poly-phenylene-vinylene: PPV ) derivatives, or polythiophene (Polythiophene) a first material made of a polymer material, C n fullerenes (here in, n represents more than 60 integer), C n fullerene derivative, CNTs having semiconducting (carbon nanotube), and a second material consisting of at least one of CNTs compound, a mixture of.
The conductivity type of an organic semiconductor (hereinafter referred to as “semiconductor” as appropriate) made of an organic thin film of this polymer material is the weight ratio of the mixture of the first material and the second material (first material / second material). Material) By setting x to x> 1.1 to 1.5, the conductivity type of the organic semiconductor is set to p-type, and by setting x <1.1 to 1.5, the conductivity type of the organic semiconductor is n. Can be set to type. Further, a mixing weight ratio of about 1.1 to 1.5 is a boundary between p-type and n-type, and is a simultaneous bipolar type (ammbipolar) in which p-type and n-type are mixed. In the case of the simultaneous bipolar type, a high resistance intrinsic semiconductor (i) type, a high resistance n type (n or new type), and a high resistance p type (p or pi type) can be used.

As a derivative of the above polyphenylene vinylene, MEH-PPV (poly [2-methoxy, 5- (2′-ethyl-hexyloxy) -p-phenylene-vinylene]) or the like can be used.
In addition, as a polythiophene-based polymer material, P3HT (poly (3-hexythiophene), poly (3-alkylthiophenes), F8T2 (dioctylfluorene-bithiophene copolymer), PEDOT (3,4-ethylene), and the like can be used.

As the C n fullerene derivative, and the like can be used PCBM ([6,6] -phenylC 61 -butyric acid methyl ester). In addition, a fullerene dimer, a fullerene compound into which an alkali metal, an alkaline earth metal, or the like is introduced can be used.
Furthermore, as the CNTs, carbon nanotubes containing fullerene or metal-encapsulated fullerene can be used. In addition, compounds in which various molecules are added to the side wall or the tip of CNTs can also be used.

For example, the conductivity type of the semiconductor can be changed by changing the mixing ratio x (PPV derivative / n-type fullerene (C n )) between the PPV derivative material and the n-type fullerene (C n ) -based material. Thus, the reason why the conductivity type can be controlled can be estimated as follows.
In the mixed material (x <1.1 to 1.5) in which the n-type fullerene (C n ) -based material is increased, the PPV derivative material whose characteristics of the n-type fullerene (C n ) -based material as a whole is a p-type material It is more strongly affected and becomes n-type. Conversely, when the n-type fullerene (C n ) -based material is reduced (x> 1.1 to 1.5), the characteristics of the PPV derivative-based material are stronger than those of the n-type fullerene (C n ) -based material. Influences and becomes p-type.
In the mixed material (x <1.1 to 1.5) in which the n-type fullerene (C n ) -based material is increased, the mixed material of the PPV derivative-based material and the n-type fullerene (C n ) -based material is a compound. It is also possible that the compound exhibits n-type. However, in this case, it is considered that the conductivity type does not change unless the weight ratio x of the mixed material exceeds a certain value.

  The semiconductor thin film comprising the organic thin film of the polymer material of the present invention is formed by applying an organic solvent liquid such as dichlorobenzene containing the above polymer material onto the substrate by a spin coating method or a spin casting method. can do. As another film forming method, a printing method or an ink jet method can be used. In the present invention, the film forming methods are collectively referred to as a coating film forming method.

According to the organic semiconductor layer of the present invention, the semiconductor layer can be configured by mixing the first material and the second material. In that case, since the lamination process is unnecessary only by mixing, it can be manufactured easily. And the semiconductor manufactured in this way is stable in air | atmosphere, and can make carrier mobility high.
Further, the conductivity type of the semiconductor layer can be controlled to be p-type or n-type by appropriately selecting the weight ratio of the mixture of the first material and the second material.

Next, a field effect transistor according to a second embodiment of the present invention will be described.
FIG. 1 is a schematic sectional view showing a configuration of a second embodiment of a field effect transistor according to the present invention. In FIG. 1, a field effect transistor 10 is a field effect transistor using a substrate, and sequentially from below, a gate electrode 11, a substrate 12, an insulating layer 13, a source electrode 14 and a drain electrode 15, a semiconductor layer 16, a sealing layer. It consists of a thin film layer 17.

  The semiconductor layer 16 is an n-type or p-type semiconductor layer made of a polymer material-based organic thin film according to the first embodiment of the present invention, and serves as a channel layer of the field effect transistor 10.

The substrate 12 is composed of a high concentration Si substrate having a resistivity of, for example, 0.001 to 0.005 Ωcm. Furthermore, the insulating layer 13 is, for example, a gate insulating film composed of SiO 2, Si 3 N 4, Al 2 O 3, Ta 2 O 5 or the like. The gate electrode 11 is made of a metal such as gold. The source electrode 14 and the drain electrode 15 are each composed of electrodes such as Ti / Au and Cr / Au, and are arranged on the insulating layer 13 so as to face each other so as to define a channel. Yes. Further, the sealing thin film layer 17 is made of, for example, SiO 2 , Si 3 N 4 , SiON or the like, and serves as a protective film for the field effect transistor 10.

Next, a modification of the field effect transistor according to the second embodiment of the present invention will be described. FIG. 2 is a schematic sectional view showing a configuration of a modification of the second embodiment of the field effect transistor according to the present invention.
In FIG. 2, a field effect transistor 20 is a field effect transistor using a substrate 21, and sequentially from the bottom, a substrate 21, a gate electrode 11, an insulating layer 13, a source electrode 14 and a drain electrode 15, a semiconductor layer 16, a sealing layer. It is comprised from the thin film layer 17.

  The gate electrode 11 is formed on the surface of the substrate 21 and is made of a metal such as gold. Here, as the substrate 21, for example, an insulator or an insulating and flexible PET (polyethylene terephthalate) substrate can be used.

  The insulating layer 13, the source electrode 14, the drain electrode 15, the semiconductor layer 16, and the sealing thin film layer 17 have the same configuration as the corresponding parts in the field effect transistor 10 shown in FIG.

According to the configuration of the field effect transistor of the present invention, the organic semiconductor layer serving as the channel can be formed on the substrate by a coating film forming method in the atmosphere. For this reason, since the lamination process by the conventional vapor deposition method etc. is unnecessary, the number of processes may be small. In addition, since the first material and the second material of the organic semiconductor layer are stable in the air, the field effect transistor operates stably for a long period of time, and its reliability is improved. Furthermore, since it is possible to change the conductivity type of the organic semiconductor layer, in particular, an n-type field effect transistor can be easily realized.
Thereby, a field effect transistor using a polymer material-based organic thin film can be easily configured with a simple configuration at low cost and in a short time without changing the physical properties of the first material and the second material. be able to. Furthermore, since the semiconductor layer described above has high carrier mobility, a field effect transistor having a high current driving capability and a high switching speed can be obtained.

Next, an optical field effect transistor according to a third embodiment of the present invention will be described.
The optical field effect transistor of the present invention uses the field effect transistors 10 and 20 according to the second embodiment of the present invention, and the uppermost layer 17 is a protective film that can transmit excitation light to the channel formed of the semiconductor layer 16. That's fine.

  According to the optical field effect transistor of the present invention, the current between the drain and the source of the field effect transistor changes due to the increase of carriers in the semiconductor layer serving as a channel in response to external light irradiation, thereby obtaining a large photocurrent gain. be able to.

Next, an integrated circuit according to a fourth embodiment of the present invention will be described.
The integrated circuit of the present invention can be configured using the field effect transistors 10 and 20 according to the second embodiment of the present invention. For example, an integrated circuit can be realized by forming a large number of n-type or p-type field effect transistors 20 on an insulating substrate 21 and forming a logic circuit therefrom. Further, on the substrate 21, a complementary integration comprising a complementary inverter comprising a p-type field effect transistor having a p-type semiconductor layer and an n-type field effect transistor having a n-type semiconductor layer. A circuit (CMOS integrated circuit) can be formed.

  According to the integrated circuit of the present invention, when a complementary integrated circuit structure is configured, the complementary integrated circuit structure can be easily configured by a simple process by using the same material and changing the mixing ratio. Thus, a complementary integrated circuit with low power consumption can be realized which is composed of organic thin films of p-type and n-type polymer materials.

Next, a method for manufacturing a semiconductor device according to the fifth embodiment of the present invention will be described.
The semiconductor device using the organic semiconductor layer of the present invention is the above-described field effect transistor, optical field effect transistor, integrated circuit, or the like. For example, the field effect transistor 10 is manufactured as follows.
That is, first, after cleaning the surface of the high-concentration Si substrate 12, an oxide film is formed as an insulating film 13 on the surface of the substrate 12 by a method such as substrate surface oxidation, sputtering, or vacuum deposition.

  Next, the gate electrode 11 is formed on the back surface of the substrate 12 by a method such as vacuum deposition or sputtering.

  Subsequently, the source electrode 14 and the drain electrode 15 are patterned on the surface of the insulating film 13 by photolithography. At this time, an ultrafine structure can be formed by arbitrarily setting the distance between the source and the drain and by the miniaturization accuracy of the photolithography method.

Thereafter, a step of forming the semiconductor layer 16 on the insulating film 13, the source electrode 14, and the drain electrode 15 by a coating film forming method is performed.
In this step, first, the first material and the second material are mixed at a predetermined mixing ratio, dissolved in an organic solvent such as chlorobenzene or dichlorobenzene solvent, and sufficiently stirred to dissolve uniformly. Make a mixture of polymer solutions.
At this time, by appropriately adjusting the mixing ratio x, the conductivity type of the semiconductor layer can be controlled to be p-type or n-type.

  Then, the polymer solution mixture thus mixed is applied onto the insulating film 13, the source electrode 14, and the drain electrode 15 by, for example, spin casting to form the semiconductor layer 16.

  Finally, an insulating thin film is deposited on the surface of the semiconductor layer 16 by a vacuum deposition method or the like to form the sealing thin film layer 17. In the case of a polymer material, since it is stable in the air, the sealing thin film layer 17 may be omitted, but in order to obtain more stable and reproducible electrical characteristics, the sealing thin film layer 17 is formed. In this way, the field effect transistor 10 is completed.

The field effect transistor 20 is manufactured as follows.
That is, first, the gate electrode 11 is formed on the surface of the substrate 21 by one of a vacuum evaporation method and a sputtering method.

  Next, after cleaning the surface of the gate electrode 11, an insulating film 13 is formed on the surface of the gate electrode 11 by sputtering or the like.

  Thereafter, the source electrode 14, the drain electrode 15, the semiconductor layer 16, and the sealing thin film layer 17 are formed in the same manner as the field effect transistor 10 described above. At this time, the conductivity type of the semiconductor layer 16 can be controlled to be p-type or n-type by appropriately adjusting the mixing ratio of the materials. In this way, the field effect transistor 20 is completed.

  In the above-described embodiments, the method of manufacturing a field effect transistor including an n-type or p-type semiconductor layer using a mixture of the first material and the second material according to the present invention has been described. Further, since it is possible to form p-type and / or n-type semiconductor layers on one substrate, for example, a so-called complementary integrated circuit comprising p-type and n-type semiconductor layers on the same substrate. Can be manufactured.

As a result, the conductivity type of the semiconductor layer can be changed continuously from p-type to n-type simply by changing the weight ratio of the first material and the second material of the organic semiconductor layer by the coating film forming method. In particular, an n-type field effect transistor can be easily realized.
In addition, it is possible to easily form a semiconductor integrated circuit such as a complementary integrated circuit by simultaneously forming p-type and n-type semiconductor layers on a substrate.

Next, a modification of the method for manufacturing a semiconductor device according to the fifth embodiment of the present invention will be described.
In the above-described method for manufacturing a field effect transistor, it is preferable to add a light irradiation treatment step in order to increase the driving capability of the field effect transistor. In the light irradiation treatment step, a light source in the visible to ultraviolet wavelength region is applied to the entire semiconductor layer 16 of the field effect transistor in a vacuum or a nitrogen atmosphere for a predetermined time. Next, after the light irradiation treatment, the light-irradiated field effect transistor is held in a lightless state for a predetermined time in the air or in a nitrogen atmosphere. Here, as the light source, for example, a xenon lamp having a wavelength of 300 nm to 800 nm can be used.

When the above-described light irradiation treatment step is performed on the field effect transistor, its current-voltage characteristics are improved, a large transconductance (g m ) is exhibited, and the g m is maintained. This detailed mechanism of g m improvement is unknown, it is estimated to be due to the fact that the mobility of the organic semiconductor layer is increased by light irradiation.

  According to the above manufacturing process, the mobility of the semiconductor layer is improved by the light irradiation treatment, so that the current drive capability of the field effect transistor can be improved regardless of the shortening of the channel. As a result, various semiconductor devices having a high current driving capability can be manufactured at low cost by a coating film formation method using a spin casting method or a printing process method without using a photolithography method necessary for shortening the channel. .

Using MEH-PPV as the first material and C 60 as the second material, the mixture was dissolved in dichlorobenzene and stirred for 24 hours or more.
At this time, the weight ratio x of the mixture was appropriately adjusted in a range of about 0.1 <x <9 to prepare an organic solvent liquid containing the mixture of the materials. Using this organic solvent solution, a semiconductor made of a polymer material-based organic thin film was formed on a SiO 2 -coated Si substrate by spin casting. When the weight ratio of the above mixture x = 0.33 (MEH-PPV / C 60 = 1/3), an n-type semiconductor is obtained, and its mobility is 2 × 10 −3 cm 2 / V · s. It was.

When the weight ratio was x = 4 (MEH-PPV / C 60 = 4/1) using the same material as in Example 1, a p-type semiconductor was obtained. The mobility of this p-type semiconductor was 5 × 10 −5 cm 2 / V · s. Thus, by varying the weight ratio x of the mixture of MEH-PPV and C 60, and can control the conductivity type of the n-type and p-type.
Figure 3 is a diagram showing a semiconductor mobility to weight ratio x of the mixture of MEH-PPV and C 60. In the figure, the horizontal axis represents the weight ratio x of the mixture, and the vertical axis represents the mobility (cm 2 / V · s).
As is apparent from the figure, when the weight ratio x of the mixture is x> 1.1 to 1.5, the semiconductor conductivity type is p-type, and x <1.1 to 1.5. Thus, the conductivity type of the semiconductor could be set to n-type. The region where x = 1.1 to 1.5 is a mixed region of p-type and n-type. The maximum mobility obtained in the present invention was 0.01 cm 2 / V · s due to the n-type semiconductor.

The n-type field effect transistor 10 of Example 3 was manufactured as follows. First, after cleaning the surface of the high-concentration Si substrate 12, a SiO 2 film 13 having a thickness of 500 nm was formed by a thermal oxidation method. Next, a 100 nm-thick gold thin film to be the gate electrode 11 was formed on the back surface of the Si substrate 12 by vacuum deposition. Subsequently, an interdigital structure having a source-drain distance of 50 μm and a finger number of 32, that is, a so-called comb-shaped counter electrode source electrode 14 and drain electrode 15 was formed on the surface of the oxide film 13 by photolithography. Ti / Au was used as the electrode metal. Thereafter, an n-type semiconductor layer 16 was formed on the insulating film 13, the source electrode 14, and the drain electrode 15 in the same manner as in Example 1 by spin casting. For example, after 2000 spins and 10 seconds of spin cast, 4000 spins and 1 second of spin cast are repeated three times. Thereby, the n-type semiconductor layer 16 having a thickness of 100 nm to 150 nm was formed. Finally, a 10 nm-thickness SiO 2 thin film was vapor-deposited on the surface of the n-type semiconductor layer 16 by a vacuum vapor deposition method to form a sealing thin film layer 17, thereby manufacturing the n-type field effect transistor 10 of Example 3. .

FIG. 4 is a diagram showing current-voltage (IV) characteristics of the n-type field effect transistor of Example 3. In the figure, the horizontal axis represents the drain voltage (V), and the vertical axis represents the drain current (μA).
As is clear from the figure, when a voltage of 0 to 50 V is applied between the drain and source electrodes and a gate voltage Vg of 10 to 60 V is applied to the gate electrode 11, the change in Vg is achieved when Vg> 20V. It can be confirmed that the drain current Id changes corresponding to the above, and it is understood that the so-called enhancement type IV characteristic is obtained. The g m of the n-type field effect transistor of this Example 3 was 0.02 mS / mm.

A p-type field effect transistor 10 was manufactured in the same manner as in Example 3 except that the p-type semiconductor layer was used as a channel in the same manner as in Example 2.
FIG. 5 is a graph showing current-voltage (IV) characteristics of the p-type field effect transistor of Example 4. In the figure, the horizontal axis represents the drain voltage (V), and the vertical axis represents the drain current (μA).
As is apparent from the figure, when a voltage of 0 to -50V is applied between the drain and source electrodes and a gate voltage Vg of -10 to -60V is applied to the gate electrode 11, Vg <-20V. It can be seen that the drain current Id changes corresponding to the change in Vg. Enhancement-type IV characteristics were obtained by the p-type field effect transistor of Example 4, and its g m was 1.2 × 10 −5 mS / mm.

  In the manufacturing process of the n-type field effect transistor of Example 3, a light irradiation process was further added at the end of the process to manufacture the n-type field effect transistor 10. In the n-type field effect transistor of Example 5, the entire semiconductor layer 16 of the n-type field effect transistor of Example 3 is irradiated with light for 24 hours by a xenon lamp having a wavelength of 300 nm to 800 nm in a vacuum or in a nitrogen atmosphere. Irradiation treatment was performed, and then the light was kept in the lightless state for 24 hours in air or nitrogen atmosphere.

FIG. 6 is a diagram illustrating IV characteristics of the n-type field effect transistor according to the fifth embodiment. In the figure, the horizontal axis represents the drain voltage (V), the vertical axis represents the drain current (μA) on a logarithmic scale, and the IV characteristics of Example 3 are also shown for comparison.
As is apparent from the figure, it can be seen that the drain current Id in Example 5 is 100 times or more larger than that in Example 3 in which the light irradiation process is not performed, and the current driving capability is greatly improved.

FIG. 7 is a diagram showing the time dependence of the drain current at room temperature of the n-type field effect transistor according to Example 5. In the figure, the vertical axis represents the drain current (μA) on a logarithmic scale, the horizontal axis represents time (minutes), and the characteristics of Example 3 in which the light irradiation process is not performed are also shown for comparison. The bias conditions for each drain current are Vds = 40V and Vg = 60V.
As is apparent from the figure, the drain current of the n-type field effect transistor according to Example 5 increased in a short time within about the first 2 minutes and decreased after reaching the maximum value (enclosed by the dotted line in FIG. 7). It can be seen that after about 1000 minutes, it is maintained at a substantially constant 20 μA. It can be seen that the drain current Id in Example 5 is about 10 times that of Example 3 in which the light irradiation process is not performed, and the current driving capability is greatly improved.

  The n-type field effect transistor of Example 3 was irradiated with light, and the IV characteristics of the optical field effect transistor were measured. The IV characteristics at the time of light irradiation were similar to the IV characteristics of Example 5 (see FIG. 6). That is, it was found that the drain current Id was increased 100 times or more by light irradiation, and the current driving capability was greatly improved.

It is a schematic sectional drawing which shows the structure of 2nd Embodiment of the field effect transistor by this invention. It is a schematic sectional drawing which shows the structure of the modification of 2nd Embodiment of the field effect transistor by this invention. Shows a semiconductor mobility to weight ratio x of the mixture of MEH-PPV and C 60. FIG. 6 is a diagram showing current-voltage (IV) characteristics of an n-type field effect transistor of Example 3. It is a figure which shows the current-voltage (IV) characteristic of the p-type field effect transistor of Example 4. FIG. 6 is a diagram showing IV characteristics of an n field effect transistor according to Example 5; It is a figure which shows the time dependence of the drain current in the room temperature of the n field effect transistor by Example 5. FIG.

Explanation of symbols

10, 20: Field effect transistor 11: Gate electrode 12: Substrate (Si substrate)
13: Insulating layer 14: Source electrode 15: Drain electrode 16: Semiconductor layer 17: Sealing thin film layer 21: Substrate (flexible substrate)

Claims (16)

  1. A first material comprising a polyphenylene vinylene derivative, or polythiophene-based polymer material, C n fullerenes (where, n represents more than 60 integer), C n fullerene derivative, CNTs having semiconducting (carbon nanotube), CNTs compound An organic semiconductor comprising a mixture of a second material composed of at least one of the following.
  2.   By setting the mixture weight ratio x of the first material and the second material to x> 1.1 to 1.5, the conductivity type of the organic semiconductor is set to p-type, and x <1.1 to The organic semiconductor according to claim 1, wherein the conductivity type of the organic semiconductor is set to n-type by setting to 1.5.
  3. A field effect transistor comprising an organic semiconductor layer to be a channel formed on a substrate,
    The organic semiconductor layer comprises a first material comprising a derivative or polythiophene-based polymer material of the polyphenylene vinylene, (wherein, n represents more than 60 integer) C n fullerenes, C n fullerene derivative, CNTs having semiconducting ( A field effect transistor comprising a mixture of a carbon nanotube) and a second material made of at least one of CNTs compounds.
  4.   By setting the weight ratio x of the mixture of the first material and the second material to x> 1.1 to 1.5, the conductivity type of the organic semiconductor is set to p-type, and x <1.1 The field effect transistor according to claim 3, wherein the conductivity type of the organic semiconductor is set to n-type by setting to 1.5.
  5.   The field effect transistor according to claim 3 or 4, wherein the organic semiconductor layer is formed on the substrate by a coating film forming method.
  6.   6. At least a part of the organic semiconductor layer is irradiated with light for a predetermined time in a vacuum or in a predetermined gas atmosphere to increase the mutual conductance of the field effect transistor. The field effect transistor according to any one of the above.
  7. An optical field-effect transistor comprising an organic semiconductor layer serving as a channel formed on a substrate,
    The organic semiconductor layer includes a first material made of a polyphenylene vinylene derivative or a polythiophene polymer material, a C n fullerene (where n is an integer of 60 or more), a C n fullerene derivative, semiconducting CNTs ( Carbon nanotubes) and a second material composed of at least one kind of CNTs compound,
    An optical field effect transistor, wherein a current between a drain and a source of the optical field effect transistor changes according to light irradiation to the organic semiconductor layer.
  8.   By setting the weight ratio x of the mixture of the first material and the second material to x> 1.1 to 1.5, the conductivity type of the organic semiconductor is set to p-type, and x <1.1 The field effect transistor according to claim 7, wherein the conductivity type of the organic semiconductor is set to n-type by setting to 1.5.
  9. An integrated circuit comprising an organic semiconductor layer formed on a substrate,
    The organic semiconductor layer comprises a first material comprising a derivative or polythiophene-based polymer material of the polyphenylene vinylene, (wherein, n represents more than 60 integer) C n fullerenes, C n fullerene derivative, CNTs having semiconducting ( An integrated circuit comprising a mixture of a carbon nanotube) and a second material made of at least one kind of CNTs compound.
  10.   By setting the weight ratio x of the mixture of the first material and the second material to x> 1.1 to 1.5, the conductivity type of the organic semiconductor is set to p-type, and x <1.1 The integrated circuit according to claim 9, wherein the conductivity type of the organic semiconductor is set to n-type by setting to 1.5.
  11.   The integrated circuit includes a complementary inverter composed of a p-type field effect transistor in which the conductivity type of the organic semiconductor layer is p-type and an n-type field effect transistor in which the conductivity type of the organic semiconductor layer is n-type. The integrated circuit according to claim 9, wherein the integrated circuit is a type integrated circuit.
  12. A first material comprising a polyphenylene vinylene derivative, or polythiophene-based polymer material, C n fullerenes (where, n represents more than 60 integer), C n fullerene derivative, CNTs having semiconducting (carbon nanotube), CNTs compound And a second material composed of at least one of the above, and a step of coating the mixture on a substrate by a coating film forming method to form an organic semiconductor layer. A method for manufacturing a semiconductor device.
  13.   13. The method of manufacturing a semiconductor device according to claim 12, wherein the semiconductor device having the organic semiconductor layer is any one of a field effect transistor, an optical field effect transistor, an integrated circuit, and a complementary integrated circuit.
  14.   By setting the weight ratio x of the mixture of the first material and the second material to x> 1.1 to 1.5, the conductivity type of the organic semiconductor is set to p-type, and x <1.1 14. The method of manufacturing a semiconductor device according to claim 12, wherein the conductivity type of the organic semiconductor is set to n-type by setting to 1.5.
  15.   Furthermore, the said organic-semiconductor layer is equipped with the light irradiation process of light-irradiating for a predetermined time in a vacuum or a predetermined gas atmosphere, The any one of Claims 12-15 characterized by the above-mentioned. A method for manufacturing a semiconductor device.
  16.   16. The method of manufacturing a semiconductor device according to claim 15, wherein characteristics of a field effect transistor included in the semiconductor device are adjusted by light irradiation on the organic semiconductor layer.
JP2004079094A 2004-03-18 2004-03-18 Organic semiconductor, semiconductor device using the same, and method of manufacturing the same Pending JP2005268550A (en)

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JP2008243841A (en) * 2007-03-23 2008-10-09 Sumitomo Chemical Co Ltd Composition, optical conductor thin film, and optical conductor element
JP2009176985A (en) * 2008-01-25 2009-08-06 Asahi Kasei Corp New optical field effect transistor with organic semiconductor layer
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KR20160001895A (en) * 2014-06-27 2016-01-07 동국대학교 산학협력단 Carbon nanotube organic semiconductor, thin-film transistor, chemical sensor and application using the same
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US8034890B2 (en) 2005-02-24 2011-10-11 Roskilde Semiconductor Llc Porous films and bodies with enhanced mechanical strength
US7790234B2 (en) 2006-05-31 2010-09-07 Michael Raymond Ayers Low dielectric constant materials prepared from soluble fullerene clusters
US7919188B2 (en) 2006-05-31 2011-04-05 Roskilde Semiconductor Llc Linked periodic networks of alternating carbon and inorganic clusters for use as low dielectric constant materials
US7883742B2 (en) 2006-05-31 2011-02-08 Roskilde Semiconductor Llc Porous materials derived from polymer composites
US7875315B2 (en) 2006-05-31 2011-01-25 Roskilde Semiconductor Llc Porous inorganic solids for use as low dielectric constant materials
KR101206661B1 (en) 2006-06-02 2012-11-30 삼성전자주식회사 Organic electronic device comprising semiconductor layer and source/drain electrodes which are formed from materials of same series
JP2008103717A (en) * 2006-10-18 2008-05-01 Kofukin Seimitsu Kogyo (Shenzhen) Yugenkoshi P-n junction element, its manufacturing method, and transistor using p-n junction element
KR101151096B1 (en) 2006-11-30 2012-06-01 삼성전자주식회사 Organic Thin Film Transistor Using Carbon nanotube introduced surface modification
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WO2008090969A1 (en) * 2007-01-26 2008-07-31 Toray Industries, Inc. Organic semiconductor composite, organic transistor material and organic field effect transistor
JP2008243841A (en) * 2007-03-23 2008-10-09 Sumitomo Chemical Co Ltd Composition, optical conductor thin film, and optical conductor element
KR100857542B1 (en) 2007-07-19 2008-09-08 삼성전자주식회사 Carbon nano-tube(cnt) light emitting device and a manufacturing method thereof
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JP2009176985A (en) * 2008-01-25 2009-08-06 Asahi Kasei Corp New optical field effect transistor with organic semiconductor layer
WO2009139339A1 (en) * 2008-05-12 2009-11-19 東レ株式会社 Carbon nanotube composite, organic semiconductor composite, and field-effect transistor
US8530889B2 (en) 2008-05-12 2013-09-10 Toray Industries, Inc. Carbon nanotube composite, organic semiconductor composite, and field-effect transistor
US10089930B2 (en) 2012-11-05 2018-10-02 University Of Florida Research Foundation, Incorporated Brightness compensation in a display
JP2016506068A (en) * 2012-11-30 2016-02-25 ユニバーシティー オブ フロリダ リサーチ ファウンデーション,インコーポレイテッドUniversity Of Florida Research Foundation,Inc. Ambipolar vertical field effect transistor
KR20160001895A (en) * 2014-06-27 2016-01-07 동국대학교 산학협력단 Carbon nanotube organic semiconductor, thin-film transistor, chemical sensor and application using the same
KR102062928B1 (en) * 2014-06-27 2020-01-07 동국대학교 산학협력단 Carbon nanotube organic semiconductor, thin-film transistor, chemical sensor and application using the same

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