Patent Application
20130168657
This application claims the benefit of Korean Patent Application No. 10-2012-0001147, filed on Jan. 4, 2012, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.
1. Field
The present disclosure relates to fiber transistors, and more particularly, to fiber transistors and methods of manufacturing the same.
2. Description of the Related Art
As the application field of electronic devices broadens, there is an increasing demand for flexible electronic devices which may overcome limitations of conventional electronic devices formed on substrates such as silicon (Si) and glass substrates. Thin film transistors (TFTs) used in fields such as flexible displays, smart clothing, dielectric elastomer actuators (DEA), biocompatible electrodes, and electronic devices used to detect electric signals in a living body need to be flexible and foldable. In particular, in order to manufacture a foldable TFT, each element constituting the transistor needs to be flexible.
One or more embodiments provide a thin film transistor formed on a fiber.
One or more embodiments also provide a method of manufacturing a thin film transistor formed on a fiber.
According to an aspect of an embodiment, there is provided a thin film transistor including: a fiber; a first electrode that is disposed on the fiber; a second electrode that is disposed on the fiber and space apart from the first electrode; a gate electrode that is disposed on the fiber; a channel that is disposed between the first electrode and the second electrode; and a gate insulating layer that is disposed on the first electrode, the second electrode, the gate electrode and the channel; and an encapsulant that encapsulates the gate insulating layer.
The fiber may be a natural fiber, a chemical fiber, or any mixture thereof.
The fiber may be a single fiber.
The channel may be a semiconductor thin film formed of an organic semiconductor material or a nanostructure with a fiber shape.
The organic semiconductor material may include polythiophene, polyacetylene, polypyrrole, polyphenylene, polythienyl vinylidene, polyphenylene sulfide, polyaniline, polyparaphenylene vinylene, polyparaphenylene, polyfluorene, or polythiovinylene.
The gate insulating layer may be formed of a mixture of ionic liquids or electrolytes with a resin.
The encapsulant may be a resin or a mold-forming material.
The resin may be a thermosetting or UV-curable acrylic resin, a thermosetting epoxy resin, or an elastomer resin.
The thin film transistor may be used in flexible displays, smart clothing, dielectric elastomer actuators (DEA), biocompatible electrodes or electronic devices used to detect electric signals in a living body need to be flexible and foldable.
According to an aspect of another embodiment, there is provided a method of manufacturing a thin film transistor, the method including depositing a conductive material on a fiber and patterning the deposited conductive material to form a first electrode, a second electrode, and a gate electrode on the fiber; forming a channel between the first electrode and the second electrode; forming a side wall of an encapsulant on the fiber, the first electrode, the second electrode, and the gate electrode; forming a gate insulating layer inside the side wall of the encapsulant; and forming a cover layer of the encapsulant on the gate insulating layer so that the gate insulating layer is encapsulated by the sidewall and the cover layer of the encapsulant.
The above and/or other aspects will become apparent and more readily appreciated from the following description of embodiments, taken in conjunction with the accompanying drawings in which:
Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. In this regard, the present embodiments may have different forms and should not be construed as being limited to the descriptions set forth herein. Accordingly, the embodiments are merely described below, by referring to the figures, to explain aspects of the present description.
Hereinafter, a thin film transistor (TFT) formed on a fiber, according to an embodiment, will be described in detail with reference to the drawings. In the accompanying drawings, thicknesses and sizes of layers or regions are exaggerated for clarity.
The TFT formed on the fiber according to the current embodiment includes the fiber 10 and a first electrode 11, a second electrode 12, and a gate electrode 13 which are formed on the fiber 10 and spaced apart from one another. The first electrode 11 and the second electrode 12 may be respectively a drain electrode and a source electrode, and the reverse is also possible. A channel 14 is formed between the first electrode 11 and the second electrode 12. A gate insulating layer 15 may be formed on the fiber 10, the first electrode 11, the second electrode 12, the gate electrode 13 and the channel. The gate insulating layer 15 may be encapsulated by an encapsulant 16 formed on the fiber 10, the first electrode 11, the second electrode 12, and the gate electrode 13.
In this regard, the fiber 10 may function as a substrate and may include a natural fiber, a chemical fiber, or any combination thereof with excellent smoothness, water resistance, tensile strength, and bending property. For example, the natural fiber may be produced from wood pulp, hemp, ramie, hemp cloth, or wool, and the chemical fiber may be produced from vinylon, nylon, acryl, rayon, polypropylene, or asbestos fiber. The fiber 10 may be a single fiber with various cross-section shapes such as a circular, oval, and polygonal, e.g., rectangular, cross-sections. The fiber 10 may have a length of a cross-section that is more than several times to several tens of times, for example, 100 to 1000 times, longer than a width of the cross-section.
The first electrode 11, the second electrode 12, and the gate electrode 13 may be formed of a conductive material, for example, metal, a conductive metal oxide, or a conductive polymer. For example, the metal may include aluminum (Al), gold (Au), silver (Ag), chromium (Cr), titanium (Ti), copper (Cu), tantalum (Ta), molybdenum (Mo), tungsten (W), nickel (Ni), palladium (Pd), platinum (Pt), or any alloy thereof. The conductive metal oxide may include indium tin oxide (ITO), indium zinc oxide (IZO), and the like. The conductive polymer may include polyethylene dioxythiophene:polystyrene sulphonate (PEDOT:PSS), polyaniline, polypyrrole, or any mixture thereof.
The channel 14 that is disposed between the first electrode 11 and the second electrode 12 may be a semiconductor thin film formed of an organic semiconductor material or a nanostructure with a fiber shape. The shape of the nanostructure is not limited, and may be, for example, a one-dimensional structure with a circular or polygonal cross-section. For example, the organic semiconductor material may include polythiophene, polyacetylene, polypyrrole, polyphenylene, polythienyl vinylidene, polyphenylene sulfide, polyaniline, polyparaphenylene vinylene, polyparaphenylene, polyfluorene, or polythio vinylene, and the like.
The gate insulating layer 15 is formed on the fiber 10 and on the first electrode 11, the second electrode 12, and the gate electrode 13, which are formed on the fiber 10, and the channel 14, and may be formed of a mixture of ionic liquids or electrolytes and a resin, or a gel-like polymer. As such, the resin mixed with ionic liquids has dielectric properties, is flexible, and has a high adhesion to a substrate.
In this regard, the ionic liquid is a salt including cations and anions in a liquid state. For example, the cations of the ionic liquid may include imidazolium, pyrazolium, triazolium, thiazolium, oxazolium, pyridazinium, pyrimidinium, pyrazinium, ammonium, phosphonium, guanidinium, uronium, thiouronium, pyridinium, pyrroldinium, or any mixture thereof. In addition, the anions of the ionic liquid may include halides, borate-based anions, phosphate-based anions, phosphinate-based anions, imide-based anions, sulfonate-based anions, acetate-based anions, sulfate-based anions, cyanate-based anions, thiocyanate-based anions, carbon-based anions, complex-based anions, or ClO4−.
In addition, the resin used to form the gate insulating layer 15 may be a UV-curable acrylic resin, a thermosetting epoxy resin, or an elastomer resin. For example, the resin may include poly(ethylene glycol) diacrylate, trimethylolpropane triacrylate, and dipentaerythritol hexaacrylate. The mixture of ionic liquids and a resin are cured to form an elastic gate insulating layer. The gate insulating layer 15 formed of the mixture of ionic liquids and the resin may be flexible.
The encapsulant 16 may encapsulate the material used to form the gate insulating layer 15 and may include a resin or a mold-forming material. For example, the resin may be a thermosetting or UV-curable acrylic resin, a thermosetting epoxy resin, or an elastomer resin and may include poly(ethylene glycol)diacrylate, trimethylolpropane triacrylate, and dipentaerythritol hexaacrylate.
Hereinafter, a method of manufacturing a TFT formed on a fiber, according to another embodiment of the present invention, will be described with reference to the drawings.
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According to one or more embodiments, a TFT that is formed on a single fiber and has stable characteristics may be provided.
In addition, according to one or more embodiments, there is provided a method of efficiently manufacturing a TFT formed on a single fiber.
It should be understood that the exemplary embodiments described therein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other embodiments.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2012-0001147 | Jan 2012 | KR | national |
