JPH0888418A - Piezoelectric element using ultra-thin metal film - Google Patents
Piezoelectric element using ultra-thin metal filmInfo
- Publication number
- JPH0888418A JPH0888418A JP6297194A JP29719494A JPH0888418A JP H0888418 A JPH0888418 A JP H0888418A JP 6297194 A JP6297194 A JP 6297194A JP 29719494 A JP29719494 A JP 29719494A JP H0888418 A JPH0888418 A JP H0888418A
- Authority
- JP
- Japan
- Prior art keywords
- piezoelectric
- film
- effect
- ultra
- metal
- 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.)
- Granted
Links
- 239000002184 metal Substances 0.000 title claims abstract description 34
- 239000010408 film Substances 0.000 claims abstract description 42
- 230000000694 effects Effects 0.000 claims abstract description 20
- 239000010409 thin film Substances 0.000 claims abstract description 16
- 230000005684 electric field Effects 0.000 abstract description 3
- 239000000463 material Substances 0.000 description 8
- 239000004065 semiconductor Substances 0.000 description 8
- 230000010354 integration Effects 0.000 description 3
- 238000000151 deposition Methods 0.000 description 2
- 230000005685 electric field effect Effects 0.000 description 2
- 230000005669 field effect Effects 0.000 description 2
- 239000010410 layer Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000007769 metal material Substances 0.000 description 2
- 230000005428 wave function Effects 0.000 description 2
- 229910003327 LiNbO3 Inorganic materials 0.000 description 1
- 229910003781 PbTiO3 Inorganic materials 0.000 description 1
- 229910002113 barium titanate Inorganic materials 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- WPYVAWXEWQSOGY-UHFFFAOYSA-N indium antimonide Chemical compound [Sb]#[In] WPYVAWXEWQSOGY-UHFFFAOYSA-N 0.000 description 1
- 239000012212 insulator Substances 0.000 description 1
- 238000001459 lithography Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N30/00—Piezoelectric or electrostrictive devices
- H10N30/20—Piezoelectric or electrostrictive devices with electrical input and mechanical output, e.g. functioning as actuators or vibrators
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N30/00—Piezoelectric or electrostrictive devices
- H10N30/30—Piezoelectric or electrostrictive devices with mechanical input and electrical output, e.g. functioning as generators or sensors
Landscapes
- Thin Film Transistor (AREA)
Abstract
(57)【要約】
【目的】 本発明は、圧電効果（piezo-electric effec
t）を利用したトランジスターに関するもので、特に金
属超薄膜から構成された圧電素子を提供することを目的
とする。
【構成】 本発明の圧電素子は、所定電圧により所定の
力学的な力を発生させることができる圧電膜１４と、上
記圧電膜１４の力学的な力により電気抵抗が変化されて
電子の流れを制御することができるように上記圧電膜１
４下部に形成された金属超薄膜１２から構成された電子
通路と、上記圧電膜１４上部に形成されて圧電膜１４に
圧電効果を起こすことができるように所定電圧を印加す
るための電極１６から構成されている。
【効果】 上記電極と超薄膜金属の間に電気場を印加す
る時、圧電効果による力学的な力が圧電膜下部の電子通
路の抵抗を変化させることにより、通常のトランジスタ
ーと同一な効果を発揮することができる。
(57) [Abstract] [Purpose] The present invention is directed to a piezoelectric effect (piezo-electric effec).
The present invention relates to a transistor using t), and an object thereof is to provide a piezoelectric element composed of an ultrathin metal film. According to the piezoelectric element of the present invention, a piezoelectric film 14 capable of generating a predetermined mechanical force by a predetermined voltage, and an electric resistance changed by the mechanical force of the piezoelectric film 14 to cause a flow of electrons. The piezoelectric film 1 so that it can be controlled
4 an electron path composed of the ultra-thin metal film 12 formed in the lower part, and an electrode 16 formed in the upper part of the piezoelectric film 14 for applying a predetermined voltage so that a piezoelectric effect can be generated in the piezoelectric film 14. It is configured. [Effect] When an electric field is applied between the electrode and the ultra-thin film metal, the mechanical effect due to the piezoelectric effect changes the resistance of the electron path under the piezoelectric film, thereby achieving the same effect as a normal transistor. can do.
Description
【０００１】[0001]
【産業上の利用分野】本発明は圧電効果（piezo-electr
ic effect）を利用したトランジスターに関するもの
で、特に金属超薄膜から構成された圧電効果トランジス
ターに関するものである。The present invention relates to a piezoelectric effect (piezo-electr).
ic effect) is related to the transistor, especially to the piezoelectric effect transistor composed of ultra-thin metal film.
【０００２】[0002]
【従来の技術】現在、開発され常用されている殆ど全部
の電子素子は半導体材料、特にシリコンを主材料として
製作されている。2. Description of the Related Art At present, almost all electronic devices which have been developed and used are manufactured mainly from semiconductor materials, especially silicon.
【０００３】しかし、金属を電子素子の材料として利用
する場合、半導体材料に比べていろいろな長所がある。However, the use of metal as a material for electronic devices has various advantages over semiconductor materials.
【０００４】即ち、金属の電子密度が半導体に比べて約
百万倍以上大きいため遥かに小型の素子が可能である。That is, since the electron density of metal is about one million times higher than that of semiconductor, a much smaller element is possible.
【０００５】なお、金属を利用した電子素子はバンドギ
ャップを利用していないので半導体素子で要求される程
度の高結晶性を必要としないので、基板を直接電子素子
の一部分として利用せず、平らな絶縁膜の上にたやすく
薄膜を被覆して加工、例えばリソグラフィー、リフト−
オフ（lift-off）、再蒸着又は熱処理等の工程を行なう
ことにより製作することができる。Since the electronic device using metal does not use the bandgap and does not require the high crystallinity required for the semiconductor device, the substrate is not directly used as a part of the electronic device but is flat. A thin film is easily coated on the insulating film and processed, for example, lithography, lift-
It can be manufactured by performing steps such as lift-off, re-deposition or heat treatment.
【０００６】従って、超薄膜の金属から構成された単層
の回路に絶縁層を被覆し、これを一単位として、多数の
単位構造を連続的に積層して集積回路を製造することも
できる。Therefore, it is also possible to manufacture an integrated circuit by coating a single-layer circuit composed of an ultrathin film metal with an insulating layer, and using this as a unit to continuously laminate a large number of unit structures.
【０００７】このように、金属を利用した素子は一単位
の集積度が前述した理由から半導体材料の素子に比べて
遥かに増加することができるのみならず、これを、積層
して三次元化することができるために積層の個数に応じ
集積度を倍加させることができる。As described above, the device using a metal can not only be greatly increased in integration degree of one unit as compared with the device made of a semiconductor material because of the above-mentioned reason, but also can be stacked into a three-dimensional structure. Therefore, the degree of integration can be increased depending on the number of stacked layers.
【０００８】[0008]
【発明が解決しようとする課題】このような三次元構造
を可能にするには、金属薄膜を主材料とする能動素子、
即ちトランジスターが必要である。In order to enable such a three-dimensional structure, an active element mainly composed of a metal thin film,
That is, a transistor is needed.
【０００９】これまで広く常用されているトランジスタ
ーの二つの類型の中で、金属薄膜を利用した圧電素子に
適用可能なものは電界効果トランジスター（field effe
ct transistor）である。Of the two types of transistors that have been widely used so far, the one applicable to a piezoelectric element using a metal thin film is a field effect transistor.
ct transistor).
【００１０】しかし、電子密度が半導体材料に比べて遥
かに大きい金属材料の特性上、電界効果によりエナージ
ーバンドが歪む表面への深さが数オングストローム
（０．１ｎｍ）程度に過ぎないために、金属薄膜の厚さ
も又その程度に薄い場合にのみ満足する程度の電界効果
を収めることができる。However, due to the characteristics of a metal material having an electron density much higher than that of a semiconductor material, the depth to the surface where the energy band is distorted by the electric field effect is only about several angstroms (0.1 nm), and The thickness of the thin film can also contain a satisfactory electric field effect only when the thickness is thin.
【００１１】現在の工程技術でこのような超薄膜を均一
に蒸着することができる装備と金属材料は有り触れてい
ない。[0011] There is no mention of equipment and metal materials capable of uniformly depositing such ultra-thin films with current process technology.
【００１２】従って、本発明は上記電界効果トランジス
ター以外の金属超薄膜材料に適合した新たな概念の素子
の要求に応えるためになされたもので、その目的は圧電
効果を利用した金属超薄膜から構成された圧電素子（pi
ezo electric device）を提供することにある。Therefore, the present invention has been made in order to meet the demand for a device of a new concept that is suitable for an ultra-thin metal film material other than the above-mentioned field effect transistor. Piezoelectric element (pi
ezo electric device).
【００１３】[0013]
【課題を解決するための手段】上記目的を達成するため
の本発明の金属超薄膜から構成された圧電素子は、所定
電圧により所定の力学的な力を発生させることのできる
圧電膜、上記圧電膜の力学的な力により電気抵抗が変化
されて電子の流れを制御することのできるように上記圧
電膜下部に形成された金属超薄膜から構成された電子通
路、及び上記圧電膜上部に形成され圧電膜に圧電効果を
起こすことができるように所定電圧を印加するための電
極から構成される。In order to achieve the above object, a piezoelectric element composed of an ultrathin metal film of the present invention is a piezoelectric film capable of generating a predetermined mechanical force by a predetermined voltage. An electron path formed of an ultrathin metal film formed under the piezoelectric film and an electric path formed over the piezoelectric film so that the electric resistance is changed by the mechanical force of the film to control the flow of electrons. It is composed of electrodes for applying a predetermined voltage so that a piezoelectric effect can be generated in the piezoelectric film.
【００１４】[0014]
【作用】この発明においては、電極に所定電圧を印加す
ると、その下部に形成された圧電膜に圧電効果が生じ、
圧電膜の力学的な力によりその下部に形成された金属超
薄膜の電気抵抗が変化して電子の流れが制御される。In the present invention, when a predetermined voltage is applied to the electrodes, a piezoelectric effect is produced in the piezoelectric film formed below the electrodes.
Due to the mechanical force of the piezoelectric film, the electric resistance of the ultra-thin metal film formed thereunder changes to control the flow of electrons.
【００１５】[0015]
【実施例】以下、本発明の望ましい実施例を添付図面を
参照してより詳細に説明する。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
【００１６】圧電効果とは所定の材料（又は結晶）に電
場を印加すれば一定の方向に力学的な力（strain）が発
生する現象で、圧電効果が発生する代表的な物質にはqu
artz,LiNbO3,BaTiO3,PbTiO3 等のような絶縁体とZnS,Cd
Te,InSb,CdSのような半導体等がある。The piezoelectric effect is a phenomenon that a mechanical force (strain) is generated in a certain direction when an electric field is applied to a predetermined material (or crystal), and a typical substance that causes the piezoelectric effect is qu
Insulators such as artz, LiNbO3, BaTiO3, PbTiO3 etc. and ZnS, Cd
There are semiconductors such as Te, InSb, and CdS.
【００１７】金属超薄膜から提供された原子の位置か
ら、その近隣の原子への電子輸送は二つの原子を中心と
した一つの電子波動関数の重畳に非常に敏感に左右され
る。Electron transport from an atomic position provided by an ultrathin metal film to neighboring atoms is very sensitive to the superposition of one electron wave function centered on two atoms.
【００１８】この波動関数の重畳された量は二つの原子
の間の距離に又指数関数的に変わるために、万一超薄膜
金属内の原子の間の距離を調節することができるなら
ば、電子輸送、即ち電気抵抗を変わるようにすることが
できる。Since the superimposed amount of this wave function varies exponentially with the distance between the two atoms, if the distance between the atoms in the ultrathin metal can be adjusted, Electron transport, ie, electrical resistance, can be varied.
【００１９】さらに、金属を超薄膜に形成することがで
きると、相対的に少ない力学的な力により望ましい金属
薄膜内の原子の間の距離を容易に変わるようにすること
ができる。Furthermore, if the metal can be formed into an ultra-thin film, the desired distance between atoms in the metal thin film can be easily changed with relatively little mechanical force.
【００２０】従って、圧電効果を利用した力学的な力を
用いるならば通常のトランジスターと同様な機能を具現
することができる。Therefore, if a mechanical force utilizing the piezoelectric effect is used, the same function as a normal transistor can be realized.
【００２１】図１は本発明の第１の望ましい実施例によ
る金属薄膜圧電効果トランジスターの構造を示した図面
で、金属超薄膜１２を電子通路であるチャンネルとし
て、上記金属超薄膜１２上部に順次的に形成された圧電
膜１４と電極１６から構成される。FIG. 1 is a view showing the structure of a metal thin film piezoelectric effect transistor according to a first preferred embodiment of the present invention, in which the metal ultra thin film 12 serves as a channel which is an electron passage and is sequentially formed on the metal ultra thin film 12. It is composed of the piezoelectric film 14 and the electrode 16 formed on the.
【００２２】このような構成を有する本発明の圧電素子
は、ゲート役割を行なう上記電極１６とソース及びドレ
イン役割を行なう金属超薄膜１２の間に電気場を印加す
る時、圧電膜１４に圧電効果による力学的な力、例えば
ストレス（stress）又はストレイン（strain）が発生
し、この力により圧電膜１４下部に形成された金属超薄
膜１２である電子通路の抵抗を変化させるものである。In the piezoelectric element of the present invention having such a structure, when an electric field is applied between the electrode 16 acting as a gate and the ultrathin metal film 12 acting as a source and a drain, a piezoelectric effect is exerted on the piezoelectric film 14. A mechanical force, for example, a stress or a strain is generated by the force, and the force changes the resistance of the electron path which is the ultra-thin metal film 12 formed under the piezoelectric film 14.
【００２３】図２（Ａ）は本発明の第２の望ましい実施
例による金属薄膜圧電素子の構造を示した平面図であ
り、図２（Ｂ）は図２（Ａ）のＡ−Ａ線断面構造を図示
したものである。図２（Ａ）（Ｂ）において図示された
圧電素子は金属超薄膜２２を電子通路として、その上に
圧電膜２４を形成し、そしてこの圧電膜２４の上で互い
に電気的に隔離されている二つの電極２６ａ，２６ｂを
向き合うように形成させた構造を有している。このよう
な圧電素子において、二つの電極２６ａ，２６ｂに電圧
を印加し電極の間の圧電膜２４に力学的な力が印加され
るようにして、その力が圧電膜２４下部の金属超薄膜２
２に作用して、その部分の電子通路の抵抗を変化させ
る。FIG. 2A is a plan view showing the structure of a metal thin-film piezoelectric element according to a second preferred embodiment of the present invention, and FIG. 2B is a cross-sectional view taken along line AA of FIG. 1 is a diagram illustrating a structure. 2A and 2B, the ultrathin metal film 22 is used as an electron passage to form a piezoelectric film 24 thereon, and the piezoelectric film 24 is electrically isolated from each other. It has a structure in which two electrodes 26a and 26b are formed so as to face each other. In such a piezoelectric element, a voltage is applied to the two electrodes 26a and 26b so that a mechanical force is applied to the piezoelectric film 24 between the electrodes, and the force is applied to the metal ultrathin film 2 below the piezoelectric film 24.
2 to change the resistance of the electron path in that portion.
【００２４】[0024]
【発明の効果】以上説明したように、本発明は次世代電
子素子の主材料として用いられることができる金属超薄
膜を利用して圧電素子を製造することにより、通常の半
導体で形成された圧電素子と同一な効果を発揮しながら
も高速化及び三次元化の集積が可能である。As described above, according to the present invention, by manufacturing a piezoelectric element using an ultrathin metal film that can be used as a main material of a next-generation electronic element, a piezoelectric element formed of a normal semiconductor is used. It is possible to achieve higher speed and three-dimensional integration while exhibiting the same effect as the device.
【図１】 本発明の第１の望ましい実施例による金属薄
膜圧電効果トランジスターの構造を示した断面図であ
る。FIG. 1 is a sectional view showing a structure of a metal thin film piezoelectric effect transistor according to a first preferred embodiment of the present invention.
【図２】 本発明の第２の望ましい実施例による金属薄
膜圧電素子の構造を示した平面図とそのＡ−Ａ線断面図
である。FIG. 2 is a plan view showing a structure of a metal thin film piezoelectric element according to a second preferred embodiment of the present invention, and a sectional view taken along line AA of FIG.
１２，２２ 金属超薄膜、１４，２４ 圧電膜、１６，
２６ 電極12,22 Ultra-thin metal film, 14,24 Piezoelectric film, 16,
26 electrodes
Claims (1)
きる圧電膜、 上記圧電膜の力学的な力により電気抵抗が変化されて電
子の流れを制御することができるように、上記圧電膜下
部に形成された金属超薄膜から構成された電子通路、及
び上記圧電膜上部に形成されて圧電膜に圧電効果を起こ
すことができるように所定電圧を印加するための電極か
ら構成されたことを特徴とする金属超薄膜を利用した圧
電素子。1. A piezoelectric element utilizing a piezoelectric effect, wherein: a piezoelectric film capable of generating a predetermined mechanical force by a predetermined voltage; and a flow of electrons whose electrical resistance is changed by the mechanical force of the piezoelectric film. And an electronic path formed of a metal ultra-thin film formed below the piezoelectric film, and a predetermined voltage formed above the piezoelectric film so as to generate a piezoelectric effect on the piezoelectric film. A piezoelectric element using a metal ultra-thin film, comprising an electrode for applying voltage.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1019940022872A KR0148420B1 (en) | 1994-09-10 | 1994-09-10 | Piezoelectric device using thin metal film |
| KR94-22872 | 1994-09-10 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0888418A true JPH0888418A (en) | 1996-04-02 |
| JP2660166B2 JP2660166B2 (en) | 1997-10-08 |
Family
ID=19392506
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6297194A Expired - Fee Related JP2660166B2 (en) | 1994-09-10 | 1994-11-30 | Piezoelectric element using ultra-thin metal film |
Country Status (2)
| Country | Link |
|---|---|
| JP (1) | JP2660166B2 (en) |
| KR (1) | KR0148420B1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005347364A (en) * | 2004-06-01 | 2005-12-15 | National Institute Of Advanced Industrial & Technology | Extendable piezoelectric element |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102008008931B3 (en) | 2008-02-13 | 2009-07-16 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. | Device for operating electrical signal of integrated circuit, has component, which has p-doped area with connection and n-doped area with another connection, and another component is provided, which is coupled with former component |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01204484A (en) * | 1988-02-09 | 1989-08-17 | Nec Corp | Superconductor electronic device |
-
1994
- 1994-09-10 KR KR1019940022872A patent/KR0148420B1/en not_active Expired - Fee Related
- 1994-11-30 JP JP6297194A patent/JP2660166B2/en not_active Expired - Fee Related
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01204484A (en) * | 1988-02-09 | 1989-08-17 | Nec Corp | Superconductor electronic device |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005347364A (en) * | 2004-06-01 | 2005-12-15 | National Institute Of Advanced Industrial & Technology | Extendable piezoelectric element |
Also Published As
| Publication number | Publication date |
|---|---|
| KR0148420B1 (en) | 1998-10-15 |
| KR960012587A (en) | 1996-04-20 |
| JP2660166B2 (en) | 1997-10-08 |
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