JPH07118270B2 - Carbon nanotube transistor - Google Patents
Carbon nanotube transistorInfo
- Publication number
- JPH07118270B2 JPH07118270B2 JP5266644A JP26664493A JPH07118270B2 JP H07118270 B2 JPH07118270 B2 JP H07118270B2 JP 5266644 A JP5266644 A JP 5266644A JP 26664493 A JP26664493 A JP 26664493A JP H07118270 B2 JPH07118270 B2 JP H07118270B2
- Authority
- JP
- Japan
- Prior art keywords
- nanotube
- electrode
- transistor
- electrons
- carbon nanotube
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y10/00—Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
- H10K10/00—Organic devices specially adapted for rectifying, amplifying, oscillating or switching; Organic capacitors or resistors having a potential-jump barrier or a surface barrier
- H10K10/40—Organic transistors
- H10K10/46—Field-effect transistors, e.g. organic thin-film transistors [OTFT]
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
- H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
- H10K85/20—Carbon compounds, e.g. carbon nanotubes or fullerenes
- H10K85/221—Carbon nanotubes
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11C—STATIC STORES
- G11C2213/00—Indexing scheme relating to G11C13/00 for features not covered by this group
- G11C2213/10—Resistive cells; Technology aspects
- G11C2213/17—Memory cell being a nanowire transistor
Description
【０００１】[0001]
【産業上の利用分野】本発明は電子回路等に用いられる
トランジスタに関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transistor used in electronic circuits and the like.
【０００２】[0002]
【従来の技術】図２は一般的な３極真空管を模式的に示
した図である。３極真空管では陰極２１と陽極２２間に
電圧を印加し、陰極２１から電子を放出させ、陽極２２
で受け取る。このときグリッド２３に正電圧をかける
と、電子はグリッドに補足され陽極２２に到達する数が
減少する。このようにグリッド２３の電圧をコントロー
ルすることによって陰極２１−陽極２２間の電流を制御
することができ、トランジスタが構成できる。またこの
トランジスタは電子の走行経路を真空に保ためガラス管
２４の中に封入されている。2. Description of the Related Art FIG. 2 is a diagram schematically showing a general triode vacuum tube. In a triode vacuum tube, a voltage is applied between the cathode 21 and the anode 22 to cause the cathode 21 to emit electrons and
Receive at. At this time, when a positive voltage is applied to the grid 23, the number of electrons that are captured by the grid and reach the anode 22 is reduced. By thus controlling the voltage of the grid 23, the current between the cathode 21 and the anode 22 can be controlled, and a transistor can be formed. Further, this transistor is enclosed in a glass tube 24 in order to keep the electron travel path vacuum.
【０００３】[0003]
【発明が解決しようとする課題】従来の技術で述べた３
極真空管は、半導体トランジスタと比べると寸法が大き
いという欠点があった。このことにより、陰極２１から
陽極２２への電子の走行時間が長い、高い印加電圧が必
要等の不都合が生じ、結果として動作が遅く消費電力が
高くなっていた。また集積化にも不向きであった。DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
The extreme vacuum tube has a drawback that it is large in size as compared with a semiconductor transistor. This causes inconveniences such as a long transit time of electrons from the cathode 21 to the anode 22 and a need for high applied voltage, resulting in slow operation and high power consumption. It was also unsuitable for integration.
【０００４】本発明は、従来の３極真空管の欠点を克服
し、半導体トランジスタを上回る性能を持ったカーボン
ナノチューブを用いた超小型で超高性能のトランジスタ
を提供することを目的としている。An object of the present invention is to overcome the drawbacks of the conventional triode vacuum tube and to provide an ultra-compact and ultra-high performance transistor using a carbon nanotube having a performance superior to that of a semiconductor transistor.
【０００５】[0005]
【発明を解決するための手段】本発明は、ゲート電極と
なるカーボンナノチューブの両端に絶縁体を介してそれ
ぞれソース・ドレイン電極が設けられ、ソース電極とド
レイン電極の間に電圧が印加されてソース電極からドレ
イン電極に向かって電子が放出され、カーボンナノチュ
ーブに印加されるゲート電圧によってドレインに到達す
る電子の数を制御することを特徴とするカーボンナノチ
ューブトランジスタである。ソース電極の電子が放出さ
れる部分は絶縁体を設けず露出しておき、電子を放出し
やすくするとよい。According to the present invention, a source / drain electrode is provided on both ends of a carbon nanotube serving as a gate electrode via an insulator, and a voltage is applied between the source electrode and the drain electrode to form a source. It is a carbon nanotube transistor characterized in that electrons are emitted from an electrode toward a drain electrode, and the number of electrons reaching the drain is controlled by a gate voltage applied to the carbon nanotube. It is preferable that the portion of the source electrode from which electrons are emitted is exposed without providing an insulator to facilitate the emission of electrons.
【０００６】[0006]
【作用】カーボンナノチューブは「固体物理」第２７
巻、第６号、第４４１頁（１９９２年）にあるようにナ
ノメートルサイズの黒鉛の円筒形の極微細管で、金属ま
たは半導体の性質を持つ導電体である。カーボンナノチ
ューブ（以下ナノチューブと略称する）の直径は２〜５
０ｎｍと極めて小さい。また円筒壁は炭素の６員環でで
きており、酸素や窒素等のガスは透過できない。そのた
めナノチューブの内側は製造時に真空であれば、その後
は真空に保たれる。[Function] Carbon nanotube is "solid state physics" No. 27
Vol. 6, No. 6, page 441 (1992), it is a cylindrical ultrafine tube of nanometer-sized graphite, which is a conductor having the properties of metal or semiconductor. The diameter of a carbon nanotube (hereinafter abbreviated as a nanotube) is 2 to 5
It is as small as 0 nm. Moreover, the cylindrical wall is made of a 6-membered ring of carbon and cannot pass gases such as oxygen and nitrogen. Therefore, if the inside of the nanotube is in vacuum at the time of manufacture, it is kept in vacuum thereafter.
【０００７】このナノチューブの内側を電子の通り道と
して真空管式トランジスタを構成すれば、ナノチューブ
に正電圧を印加することで、ナノチューブ円筒壁に電子
を引きつけることができ、電流が変調できる。このナノ
チューブ真空管式トランジスタは、ナノチューブのサイ
ズを反映して極めて小型であるため、極めて低い電圧の
印加で電流が変調できる。また電子の走行距離も短くで
き、超高速で消費電力の極めて小さなトランジスタが実
現できる。If a vacuum tube type transistor is constructed with the inside of the nanotube as a path for electrons, by applying a positive voltage to the nanotube, electrons can be attracted to the nanotube wall and the current can be modulated. Since this nanotube vacuum tube transistor is extremely small, reflecting the size of the nanotube, the current can be modulated by applying an extremely low voltage. In addition, the distance traveled by electrons can be shortened, and a transistor with ultra-high speed and extremely low power consumption can be realized.
【０００８】[0008]
【実施例】図１は本発明の実施例を説明するための図で
ある。以下図１を用いて本発明の実施例の説明を行う。FIG. 1 is a diagram for explaining an embodiment of the present invention. An embodiment of the present invention will be described below with reference to FIG.
【０００９】銅からなるソース電極１１、同じく銅から
なるドレイン電極１２とがアルミニウム酸化物からなる
絶縁体１３をそれぞれ介してナノチューブ１４で接続さ
れている。ナノチューブはゲート電極１４となる。ソー
ス電極１１とドレイン電極１２間およびナノチューブ１
４からなるゲート電極はそれぞれ独立に電圧が印加され
る。ナノチューブゲート電極１４とソース電極１１およ
びドレイン電極１２の間は絶縁体１３によって完全に絶
縁されている。ナノチューブゲート電極１４は直径が３
０ｎｍ長さが１００ｎｍである。また絶縁体１３の厚さ
はそれぞれ１０ｎｍである。A source electrode 11 made of copper and a drain electrode 12 made of copper are connected by a nanotube 14 via an insulator 13 made of aluminum oxide. The nanotube becomes the gate electrode 14. Between source electrode 11 and drain electrode 12 and nanotube 1
A voltage is independently applied to each of the four gate electrodes. The nanotube gate electrode 14 and the source electrode 11 and the drain electrode 12 are completely insulated by the insulator 13. The nanotube gate electrode 14 has a diameter of 3
The 0 nm length is 100 nm. The thickness of each insulator 13 is 10 nm.
【００１０】ナノチューブゲート電極１４の円筒壁は炭
素の６員環でできており、酸素や窒素等のガスは通過で
きない。そのため製造時にナノチューブゲート電極１４
内部が真空であるならば、その後も内部はほぼ真空に保
たれる。（ナノチューブは通常、炭素電極を用いた真空
中のアーク放電で製造する。）図１のトランジスタの動
作は以下のように行われる。まずソース電極１１とドレ
イン電極１２間に電圧が印加されると、ソース電極表面
から電子が放出され、電解に引かれてドレイン電極１２
に達する。このときナノチューブゲート電極１４に正電
圧が印加されると、前記ソース電極１１から放出された
電子の軌道は曲げられ、一部の電子がナノチューブゲー
ト電極１４の方に流れる。従って、ナノチューブゲート
電極１４に印加する電圧によってソース電極１１−ドレ
イン電極１２間の電流を変調するトランジスタ動作が得
られる。The cylindrical wall of the nanotube gate electrode 14 is made of a carbon 6-membered ring and cannot pass gases such as oxygen and nitrogen. Therefore, when manufacturing, the nanotube gate electrode 14
If the interior is a vacuum, then the interior is maintained at a near vacuum. (Nanotubes are typically manufactured by arc discharge in a vacuum using a carbon electrode.) The operation of the transistor of FIG. 1 operates as follows. First, when a voltage is applied between the source electrode 11 and the drain electrode 12, electrons are emitted from the surface of the source electrode and are attracted to electrolysis to cause drain electrode 12
Reach At this time, if a positive voltage is applied to the nanotube gate electrode 14, the orbits of the electrons emitted from the source electrode 11 are bent, and some electrons flow toward the nanotube gate electrode 14. Therefore, a transistor operation in which the current applied between the source electrode 11 and the drain electrode 12 is modulated by the voltage applied to the nanotube gate electrode 14 can be obtained.
【００１１】一般に電解電子放射を得るには１０7 Ｖ／
ｃｍ程度の電解強度が必要であるが、ソース電極１１と
ドレイン電極１２間の距離が１２０ｎｍと極めて短いこ
とと、ソース電極１１とドレイン電極１２の先端は３０
ｎｍ程度であり著しく劣っており電解強度が高いことか
ら、ｍＶオーダーの電圧で動作させることが可能であ
る。またゲート電圧とソースドレイン電圧の比は、ナノ
チューブゲート電極１４の半径とソース電極１１とドレ
イン電極１２間の比（本実施例の場合１：８）に比例す
るため、ゲート電圧はソースドレイン電圧よりさらに低
くすることができ、高いゲインが得られる。Generally, to obtain electrolytic electron emission, 10 7 V /
Although an electrolytic strength of about cm is required, the distance between the source electrode 11 and the drain electrode 12 is extremely short at 120 nm, and the tips of the source electrode 11 and the drain electrode 12 are 30
It is possible to operate at a voltage on the order of mV, because it is about nm, which is extremely inferior, and the electrolytic strength is high. Since the ratio of the gate voltage to the source / drain voltage is proportional to the radius of the nanotube gate electrode 14 and the ratio between the source electrode 11 and the drain electrode 12 (1: 8 in this embodiment), the gate voltage is more than the source / drain voltage. It can be further lowered, and high gain can be obtained.
【００１２】以上説明したように本実施例を用いれば、
低電圧で動作しかも高いゲインを有するトランジスタが
得られる。低電圧動作のドランジスタはスイッチ時間が
短く、消費電力が小さくなる。また、ナノチューブの寸
法を反映して、超小型のトランジスタを構成できる。As described above, according to this embodiment,
A transistor that operates at a low voltage and has a high gain can be obtained. The transistor operating at low voltage has a short switching time and consumes less power. In addition, an ultra-small transistor can be constructed by reflecting the dimensions of the nanotube.
【００１３】ここで、このトランジスタの製造方法を説
明する。まずアーク放電等で絶縁基板上にナノチューブ
を堆積させ、真空を破らずに別のチャンバーに移す。次
に真空蒸着法でアルミニウム薄膜を厚さ数ｎｍ堆積す
る。次にまた別のチャンバに移して酸素プラズマ中で酸
化してアルミニウム酸化物を形成する。さらに別のチャ
ンバに移送してから、基板を大きく傾けてアルゴンを用
いた異方性エッチングを行うと、ナノチューブの両端の
アルミニウム酸化物が除去されナノチューブの両端を開
口することがきる。その後銅の薄膜を形成する。これは
銅を構成元素として含むガス（有機金属化合物など）を
基板上に流し、きわめて細く絞った電子ビームをナノチ
ューブの両端のソース・ドレイン電極となる部分にだけ
照射してガスを分解するとそこに銅薄膜パターンを堆積
できる。なお電極パターンを形成するには、電子ビーム
の照射以外に、ＳＴＭ（Ｓｃａｎｎｉｎｇ Ｔｕｎｎｅ
ｌｉｎｇ Ｍｉｃｒｏｓｃｏｐｅ）用の微細な針を、電
極を形成すべき部分に位置合わせし、前記のガスを流
し、基板との間に電流を流してガスを分解する方法もあ
る。Now, a method of manufacturing this transistor will be described. First, nanotubes are deposited on an insulating substrate by arc discharge or the like and transferred to another chamber without breaking the vacuum. Next, an aluminum thin film is deposited to a thickness of several nm by the vacuum evaporation method. Then, it is transferred to another chamber and oxidized in oxygen plasma to form aluminum oxide. When the substrate is further moved to another chamber and anisotropically etched with argon while tilting the substrate largely, aluminum oxide on both ends of the nanotube is removed and both ends of the nanotube can be opened. After that, a copper thin film is formed. This is because a gas (organic metal compound, etc.) containing copper as a constituent element is made to flow over the substrate, and an extremely narrowed electron beam is applied only to the source / drain electrodes at both ends of the nanotube to decompose the gas. Copper thin film patterns can be deposited. In addition to the electron beam irradiation, an STM (scanning tunnel) is used to form the electrode pattern.
There is also a method in which a fine needle for a ring microscope is aligned with a portion where an electrode is to be formed, the above gas is caused to flow, and an electric current is passed between the gas and the substrate to decompose the gas.
【００１４】[0014]
【発明の効果】以上説明したように本発明は、ナノチュ
ーブを用いることで、極めて小型で、低電圧動作が可能
なトランジスタを提供できる。このようなトランジスタ
はスイッチング速度が大きく、消費電力が小さい等非常
に優れたトランジスタである。As described above, according to the present invention, by using the nanotube, it is possible to provide an extremely small-sized transistor capable of operating at a low voltage. Such a transistor is a very excellent transistor because of its high switching speed and low power consumption.
【図１】本発明の実施例を説明するためのカーボンナノ
チューブを用いたトランジスタの概略図。FIG. 1 is a schematic view of a transistor using a carbon nanotube for explaining an example of the present invention.
【図２】従来の技術を説明するための３極真空管の概略
図。FIG. 2 is a schematic view of a triode vacuum tube for explaining a conventional technique.
１１ ソース電極 １２ ドレイン電極 １３ 絶縁体 １４ カーボンナノチューブゲート電極 ２１ 陰極 ２２ 陽極 ２３ グリッド ２４ ガラス管 11 Source Electrode 12 Drain Electrode 13 Insulator 14 Carbon Nanotube Gate Electrode 21 Cathode 22 Anode 23 Grid 24 Glass Tube
Claims (2)
の両端に絶縁体を介してそれぞれソース・ドレイン電極
が設けられ、ソース電極とドレイン電極の間に電圧が印
加されてソース電極からドレイン電極に向かって電子が
放出され、カーボンナノチューブに印加されるゲート電
圧によってドレインに到達する電子の数を制御すること
を特徴とするカーボンナノチューブトランジスタ。1. A source / drain electrode is provided on both ends of a carbon nanotube serving as a gate electrode via an insulator, and a voltage is applied between the source electrode and the drain electrode to direct electrons from the source electrode toward the drain electrode. A carbon nanotube transistor characterized in that the number of electrons that are emitted and are controlled by the gate voltage applied to the carbon nanotubes reach the drain.
縁体が設けられていない請求項１に記載のカーボンナノ
チューブトランジスタ。2. The carbon nanotube transistor according to claim 1, wherein an insulator is not provided in a portion of the source electrode where electrons are emitted.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5266644A JPH07118270B2 (en) | 1993-10-25 | 1993-10-25 | Carbon nanotube transistor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5266644A JPH07118270B2 (en) | 1993-10-25 | 1993-10-25 | Carbon nanotube transistor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH07122198A JPH07122198A (en) | 1995-05-12 |
| JPH07118270B2 true JPH07118270B2 (en) | 1995-12-18 |
Family
ID=17433697
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5266644A Expired - Lifetime JPH07118270B2 (en) | 1993-10-25 | 1993-10-25 | Carbon nanotube transistor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07118270B2 (en) |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE69728410T2 (en) | 1996-08-08 | 2005-05-04 | William Marsh Rice University, Houston | MACROSCOPICALLY MANIPULATED DEVICES MANUFACTURED FROM NANOROE ASSEMBLIES |
| DE69942585D1 (en) * | 1998-09-07 | 2010-08-26 | Quantum Prec Instr Asia Pte Lt | MEASUREMENTS BETWEEN LONG-RUNNING LADDERS USING THE TUNNEL STREAM |
| KR100636951B1 (en) * | 1999-02-22 | 2006-10-19 | 조셉 이. 쥬니어 클로손 | Nanostructure device and apparatus |
| JP2001135251A (en) * | 1999-03-15 | 2001-05-18 | Toshiba Corp | Multielectrode electron tube |
| AU2001236763A1 (en) * | 2000-02-07 | 2001-08-14 | Xidex Corporation | System and method for fabricating logic devices comprising carbon nanotube transistors |
| WO2002063693A1 (en) * | 2001-02-08 | 2002-08-15 | Hitachi, Ltd. | Carbon nanotube electronic device and electron source |
| US7084507B2 (en) | 2001-05-02 | 2006-08-01 | Fujitsu Limited | Integrated circuit device and method of producing the same |
| KR100426495B1 (en) * | 2001-12-28 | 2004-04-14 | 한국전자통신연구원 | Semiconductor device using a single carbon nanotube and a method for manufacturing of the same |
| US7276285B2 (en) * | 2003-12-31 | 2007-10-02 | Honeywell International Inc. | Nanotube fabrication basis |
| US7329931B2 (en) | 2004-06-18 | 2008-02-12 | Nantero, Inc. | Receiver circuit using nanotube-based switches and transistors |
| WO2013011399A1 (en) * | 2011-07-20 | 2013-01-24 | Koninklijke Philips Electronics N.V. | Vaccum nano electronic switching and circuit elements. |
-
1993
- 1993-10-25 JP JP5266644A patent/JPH07118270B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH07122198A (en) | 1995-05-12 |
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