JP2778879B2 - Forming method of small drive mechanism - Google Patents
Forming method of small drive mechanismInfo
- Publication number
- JP2778879B2 JP2778879B2 JP23864892A JP23864892A JP2778879B2 JP 2778879 B2 JP2778879 B2 JP 2778879B2 JP 23864892 A JP23864892 A JP 23864892A JP 23864892 A JP23864892 A JP 23864892A JP 2778879 B2 JP2778879 B2 JP 2778879B2
- Authority
- JP
- Japan
- Prior art keywords
- substrate
- film
- cantilever
- nickel
- iron alloy
- 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
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- Physical Vapour Deposition (AREA)
- ing And Chemical Polishing (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は各種半導体デバイスの製
造工程で用いられる反応ガスの微小流量制御に有利な電
磁弁、および通信分野に用いられる機械スイッチなどの
小形駆動機構の形成方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a solenoid valve which is advantageous in controlling a minute flow rate of a reaction gas used in a manufacturing process of various semiconductor devices, and a small driving mechanism such as a mechanical switch used in a communication field.
【０００２】[0002]
【従来の技術】半導体デバイスの製造工程において、Ｃ
ＶＤ法（化学的気相堆積法）は各種薄膜の作製プロセス
として重要な役割を果たしており、さらにその反応ガス
の流量制御に用いられる小形弁には高い性能が要求され
る。従来の電磁力を用いた小形弁では弁の主要部分であ
る駆動機構は機械加工で作製するため高い精度が得られ
ないなど問題があった。また通信分野の信号の切替に用
いられる機械スイッチでは主要部分である板バネは機械
加工または放電加工などで作製するため小形化が困難で
あった。2. Description of the Related Art In a semiconductor device manufacturing process, C
The VD method (chemical vapor deposition method) plays an important role as a process for producing various thin films, and high performance is required for a small valve used for controlling the flow rate of the reaction gas. In a conventional small valve using electromagnetic force, there is a problem that a high accuracy cannot be obtained because a drive mechanism which is a main part of the valve is manufactured by machining. Further, in a mechanical switch used for switching signals in the communication field, a leaf spring, which is a main part, is manufactured by machining or electric discharge machining, so that miniaturization is difficult.
【０００３】[0003]
【発明が解決しようとする課題】本発明は上記問題点に
鑑みてなされたもので、駆動機構部分をさらに小形化か
つ立体構造化し、高歩留りで高精度を実現可能とする小
形駆動機構の形成方法を提供することを目的とする。SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has been made in view of the above problems. The aim is to provide a method.
【０００４】[0004]
【課題を解決するための手段及び作用】本発明は上記課
題を解決するために、中央部に貫通穴あるいは凸部を有
する基板とこの基板の表面に前記貫通穴あるいは凸部と
接触しない構造の片持ち梁もしくは両持ち梁で一体化構
成される骨組み構造を外部コイルで駆動する小形駆動機
構の形成方法において、前記基板を構成するシリコンお
よびニッケル鉄合金膜あるいは窒化シリコン膜からなる
基板と前記梁を構成するニッケル鉄合金膜からなる片持
ち梁もしくは両持ち梁をスパッタ法、イオンエッチング
法および異方性エッチング法で作製することを特徴と
し、又、基板と片持ち梁もしくは両持ち梁との一体化構
成の作製工程において、犠牲層としてＳｉＯ2 、ホトレ
ジストおよびアルミニウムのうち何れかを用いることを
特徴とする。したがって、ホトリソグラフィ技術と薄膜
技術とで駆動機構の主要構成部分をシリコン基板上に一
体形成することにより高い寸法精度が得られる。また、
薄膜で立体構造の駆動機構を形成する工程で、犠牲層を
用いて片持ち梁もしくは両持ち梁が仮固定される。その
後、最終工程で犠牲層は除去され、立体構造の駆動機構
が形成される。作製工程の途上で使用する犠牲層材料を
最適化することで高い歩留りを実現できる。SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a substrate having a through hole or a convex portion at the center and a structure which does not contact the through hole or the convex portion on the surface of the substrate. In a method for forming a small driving mechanism for driving a framed structure integrally formed by a cantilever or a cantilever with an external coil, a substrate comprising a silicon and nickel-iron alloy film or a silicon nitride film constituting the substrate and the beam The method is characterized in that a cantilever or a double-supported beam made of a nickel-iron alloy film is formed by a sputtering method, an ion etching method, and an anisotropic etching method. In the manufacturing process of the integrated structure, any one of SiO 2 , photoresist, and aluminum is used as the sacrificial layer. Therefore, high dimensional accuracy can be obtained by integrally forming the main components of the drive mechanism on the silicon substrate using the photolithography technique and the thin film technique. Also,
In the step of forming a three-dimensional structure driving mechanism using a thin film, a cantilever or a double-supported beam is temporarily fixed using a sacrificial layer. Thereafter, the sacrificial layer is removed in a final step, and a driving mechanism having a three-dimensional structure is formed. A high yield can be achieved by optimizing the sacrificial layer material used during the manufacturing process.
【０００５】[0005]
【実施例】次に本発明の実施例について図面を参照して
説明する。図１（ａ）、（ｂ）は本発明の実施例であ
り、卍型の両持ち梁を用いた駆動機構を示している。図
２（ａ）〜（ｆ）は図１の実施例のような両持ち梁を用
いた小形駆動機構の作製プロセスを示す。図３（ａ）、
（ｂ）は片持ち梁を用いた駆動機構を示している。Next, an embodiment of the present invention will be described with reference to the drawings. FIGS. 1A and 1B show an embodiment of the present invention, and show a drive mechanism using a swastika-shaped doubly supported beam. FIGS. 2A to 2F show a manufacturing process of a small drive mechanism using a double-supported beam as in the embodiment of FIG. FIG. 3 (a),
(B) shows a drive mechanism using a cantilever.
【０００６】図１は本発明の実施例である卍型両持ち梁
を用いた駆動機構部分の詳細図であり、（ａ）は上面
図、（ｂ）は断面図である。１はシリコン、２はニッケ
ル鉄合金膜または窒化シリコン膜からなる蓋部分、３は
軟磁性体のニッケル鉄合金膜からなる卍型両持ち梁、４
は外部コイル、５は両持ち梁の変位方向、８は貫通穴で
ある。卍型両持ち梁３の中央部は下部の蓋部分２の形状
にあわせた円錐形とした。作製方法はすべてホトリソグ
ラフィ技術と薄膜技術を用いた。構成材料はシリコンと
ニッケル鉄合金または窒化シリコンなどの薄膜を用いて
いる。中央部に円錐形の貫通穴８が設けられており、そ
の上部に蓋部分２と接触しないように卍型両持ち梁３は
セルフアラインメントで形成される。駆動機構の寸法形
状は、卍型両持ち梁３の大きさは約３００μｍ角、梁３
の幅は２０μｍ、梁３の厚さは１〜５μｍである。FIGS. 1A and 1B are detailed views of a drive mechanism using a swastika type double-supported beam according to an embodiment of the present invention. FIG. 1A is a top view and FIG. 1B is a cross-sectional view. 1 is silicon, 2 is a lid portion made of a nickel-iron alloy film or a silicon nitride film, 3 is a swastika type double-supported beam made of a soft magnetic nickel-iron alloy film, 4
Is an external coil, 5 is a displacement direction of the doubly supported beam, and 8 is a through hole. The central part of the swastika doubly supported beam 3 was formed in a conical shape corresponding to the shape of the lower lid portion 2. All fabrication methods used photolithography technology and thin film technology. As a constituent material, a thin film of silicon and a nickel-iron alloy or silicon nitride is used. A conical through-hole 8 is provided at the center, and the swastika-shaped doubly supported beam 3 is formed by self-alignment so that the through-hole 8 does not come into contact with the lid portion 2 at the upper part. The dimensions of the drive mechanism are as follows.
Has a width of 20 μm, and the thickness of the beam 3 is 1 to 5 μm.
【０００７】図２は本発明の実施例で図１のような卍型
両持ち梁を用いた小形駆動機構の作製工程を示してい
る。１０１はシリコン、１０２はニッケル鉄合金膜また
は窒化シリコン膜、１０３は軟磁性体のニッケル鉄合金
膜、１０６ａは裏面ＳｉＯ2 膜、１０６ｂは犠牲層のＳ
ｉＯ2 膜、アルミニウム膜またはホトレジスト膜、１０
７は表面ＳｉＯ2 保護膜、８は貫通穴である。作製工程
について順をおって説明すると、（ａ） シリコン単結
晶（１００）よりなるシリコン１０１の裏面にＳｉＯ2
膜１０６ａを２〜５μｍ堆積する。堆積法はＲＦスパッ
タまたはマグネトロンスパッタで行う。（ｂ） 表面に
ニッケル鉄合金膜１０２を約１０μｍ堆積し、所定のマ
スクパタンでホトリソグラフィを行いレジストマスクを
得る。このマスクを用いてニッケル鉄合金膜１０２をエ
ッチングする。エッチングはイオンビームエッチングで
パタン端部がテーパ状になるようにエッチングし、かつ
シリコン１０１を２〜５μｍオーバーエッチングするこ
とにより蓋部分２が形成される。堆積法はＲＦスパッ
タ、マグネトロンスパッタまたはイオンビームスパッタ
で行う。ここでは蓋部分２にニッケル鉄合金膜を用いた
が窒化シリコン膜でもよい。（ｃ） 蓋部分２が形成さ
れた基板上にＳｉＯ2 膜１０６ｂを２〜８μｍ堆積す
る。そののちホトリソグラフィを行い所定のレジストパ
タンマスクを得る。次にイオンビームエッチングでＳｉ
Ｏ2 膜１０６ｂをテーパエッチングし、犠牲層６ｂが形
成される。（ｄ） 犠牲層６ｂが形成された基板上にニ
ッケル鉄合金膜１０３を２μｍ堆積する。そののちホト
リソグラフィを行い両持ち梁のレジストパタンマスクを
得る。次にイオンビームエッチングでニッケル鉄合金膜
１０３をエッチングし、卍型両持ち梁３が形成される。
（ｅ） 基板全表面にＳｉＯ2保護膜１０７を約５μｍ
堆積する。次に裏面のＳｉＯ2 膜１０６ａを所定のレジ
ストマスクを用いてイオンビームエッチングでＳｉＯ2
膜１０６ａをエッチングする。そののち水酸化カリウム
水溶液（約３０％濃度）によりシリコン１０１の異方性
エッチングを行い貫通穴８を有するシリコン１が得られ
る。（ｆ） 緩衝フッ化水素酸溶液を用いて表面ＳｉＯ
2 保護膜１０７と裏面ＳｉＯ2 膜１０６ａおよび犠牲層
６ｂのＳｉＯ2 をエッチングし除去することにより図１
で示した小形駆動機構が形成される。この工程では犠牲
層６ｂにＳｉＯ2 膜を用いたがアルミニウムまたはホト
レジスト（但し熱硬化処理したもの）の場合でも同様の
効果が得られる。このような工程で形成された駆動機構
の動作は外部コイル４で駆動することにより卍型両持ち
梁３が変位し、貫通穴８の部分がふさがれる。駆動電流
の極性を切り替えることで開閉動作を行えることからガ
スなどの流量制御用の弁として応用できることがわか
る。FIG. 2 shows an embodiment of the present invention in which a small drive mechanism using a swastika-type double-supported beam as shown in FIG. 1 is manufactured. 101 is silicon, 102 is a nickel iron alloy film or a silicon nitride film, 103 is a soft magnetic nickel iron alloy film, 106a is a back surface SiO 2 film, and 106b is a sacrificial layer S
iO 2 film, aluminum film or photoresist film, 10
7 is a surface SiO 2 protective film, and 8 is a through hole. The manufacturing process will be described in order. (A) SiO 2 on the back surface of silicon 101 made of silicon single crystal (100)
The film 106a is deposited to a thickness of 2 to 5 μm. The deposition is performed by RF sputtering or magnetron sputtering. (B) A nickel-iron alloy film 102 is deposited to a thickness of about 10 μm on the surface, and photolithography is performed using a predetermined mask pattern to obtain a resist mask. Using this mask, the nickel-iron alloy film 102 is etched. Etching is performed by ion beam etching so that the pattern end is tapered, and the silicon 101 is over-etched by 2 to 5 μm to form the lid portion 2. The deposition is performed by RF sputtering, magnetron sputtering or ion beam sputtering. Here, a nickel-iron alloy film is used for the lid portion 2, but a silicon nitride film may be used. (C) On the substrate on which the lid portion 2 has been formed, an SiO 2 film 106b is deposited in a thickness of 2 to 8 μm. Thereafter, photolithography is performed to obtain a predetermined resist pattern mask. Then, ion beam etching
The O 2 film 106b is taper-etched to form the sacrificial layer 6b. (D) A 2 μm nickel-iron alloy film 103 is deposited on the substrate on which the sacrificial layer 6b is formed. Thereafter, photolithography is performed to obtain a double-sided resist pattern mask. Next, the nickel-iron alloy film 103 is etched by ion beam etching, and the swastika-type double-supported beam 3 is formed.
(E) A SiO 2 protective film 107 of about 5 μm is formed on the entire surface of the substrate.
accumulate. Then SiO 2 by ion beam etching back surface of the SiO 2 film 106a using a predetermined resist mask
The film 106a is etched. After that, the silicon 101 is anisotropically etched with a potassium hydroxide aqueous solution (about 30% concentration) to obtain the silicon 1 having the through holes 8. (F) Surface SiO using buffered hydrofluoric acid solution
Figure by the second protective layer 107 and the back surface SiO 2 film 106a and the SiO 2 sacrificial layer 6b etched to remove 1
Is formed. In this step, an SiO 2 film was used for the sacrificial layer 6b, but the same effect can be obtained in the case of aluminum or a photoresist (however, a material subjected to a thermosetting treatment). The operation of the drive mechanism formed in such a step is displaced by driving the external coil 4 to displace the swastika-shaped doubly supported beam 3 and the portion of the through hole 8 is closed. Since the switching operation can be performed by switching the polarity of the drive current, it can be seen that the valve can be applied as a valve for controlling the flow rate of gas or the like.
【０００８】図３は本発明の他の実施例で片持ち梁を用
いた駆動機構の詳細図で、（ａ）は上面図、（ｂ）は断
面図であり、２０１はシリコン、２０２はニッケル鉄合
金膜または窒化シリコン膜、２０３は軟磁性体のニッケ
ル鉄合金膜からなる片持ち梁、２０４は外部コイル、２
０６はＳｉＯ2 膜、アルミニウムまたはホトレジストか
らなる犠牲層、２０９はニッケル鉄合金膜または窒化シ
リコン膜２０２の凸部、２０９ａは金または銀パラジウ
ム膜である。作製方法は図２で示した工程とほぼ同様
で、ホトリソグラフィ技術と薄膜技術で行う。構成膜の
堆積法はＲＦスパッタ、マグネトロンスパッタおよびイ
オンビームスパッタを用い、エッチングはイオンビーム
エッチングおよび異方性エッチングで所定のパタン形成
を行う。犠牲層２０６は作製の最終工程で除去される。
この駆動機構の動作は外部コイル２０４で駆動すると片
持ち梁２０３が変位し下部に形成した凸部２０９に接触
する。駆動電流を切り替えることでスイッチング動作を
行うことが可能であり、凸部２０９の接触部分に金また
は銀パラジウム膜２０９ａなどの接点材料を設けること
により、通信用の信号切替などの機械スイッチの駆動機
構に応用できることがわかる。FIG. 3 is a detailed view of a drive mechanism using a cantilever according to another embodiment of the present invention. FIG. 3 (a) is a top view, FIG. 3 (b) is a sectional view, 201 is silicon, 202 is nickel. 203 is a cantilever made of a soft magnetic nickel-iron alloy film, 204 is an external coil,
Reference numeral 06 denotes a sacrificial layer made of an SiO 2 film, aluminum or photoresist, 209 denotes a protrusion of a nickel-iron alloy film or a silicon nitride film 202, and 209a denotes a gold or silver palladium film. The fabrication method is almost the same as the process shown in FIG. 2, and is performed by a photolithography technique and a thin film technique. RF sputtering, magnetron sputtering and ion beam sputtering are used for the deposition of the constituent films, and a predetermined pattern is formed by ion beam etching and anisotropic etching. The sacrificial layer 206 is removed in the final step of the fabrication.
When the driving mechanism is driven by the external coil 204, the cantilever 203 is displaced and comes into contact with the convex portion 209 formed at the lower portion. The switching operation can be performed by switching the driving current. By providing a contact material such as a gold or silver palladium film 209a at the contact portion of the projection 209, a driving mechanism of a mechanical switch such as signal switching for communication is provided. It can be seen that it can be applied to
【０００９】[0009]
【発明の効果】以上説明したように本発明を用いれば、
３次元の立体構造の薄膜駆動機構が高い歩留りと高い精
度で得られる。According to the present invention as described above,
A thin film driving mechanism having a three-dimensional structure can be obtained with high yield and high accuracy.
【図１】本発明の実施例の卍型両持ち梁を用いた駆動機
構を示し、（ａ）は上面図、（ｂ）は断面図である。FIGS. 1A and 1B show a drive mechanism using a swastika type double-supported beam according to an embodiment of the present invention, wherein FIG. 1A is a top view and FIG.
【図２】（ａ）〜（ｆ）は本発明の実施例で図１で示し
た駆動機構の作製工程図の一例を示す断面図である。2 (a) to 2 (f) are cross-sectional views showing an example of a manufacturing process diagram of the drive mechanism shown in FIG. 1 in an embodiment of the present invention.
【図３】本発明の他の実施例の片持ち梁を用いた駆動機
構を示し、（ａ）は上面図、（ｂ）は断面図である。3A and 3B show a drive mechanism using a cantilever according to another embodiment of the present invention, wherein FIG. 3A is a top view and FIG. 3B is a cross-sectional view.
１…シリコン、２…ニッケル鉄合金膜または窒化シリコ
ン膜からなる蓋部分、３…ニッケル鉄合金膜からなる両
持ち梁、４…外部コイル、５…両持ち梁の変位方向、８
…貫通穴。DESCRIPTION OF SYMBOLS 1 ... Silicon, 2 ... Cover part which consists of a nickel iron alloy film or a silicon nitride film, 3 ... Doubly supported beam made of a nickel iron alloy film, 4 ... External coil, 5 ... Displacement direction of doubly supported beam, 8
… Through holes.
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.6，ＤＢ名) C23F 4/00 C23C 14/34 H01L 21/3065──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. 6 , DB name) C23F 4/00 C23C 14/34 H01L 21/3065
Claims (2)
板とこの基板の表面に前記貫通穴あるいは凸部と接触し
ない構造の片持ち梁もしくは両持ち梁で一体化構成され
る骨組み構造を外部コイルで駆動する小形駆動機構の形
成方法において、前記基板を構成するシリコンおよびニ
ッケル鉄合金膜あるいは窒化シリコン膜からなる基板と
前記梁を構成するニッケル鉄合金膜からなる片持ち梁も
しくは両持ち梁をスパッタ法、イオンエッチング法およ
び異方性エッチング法で作製することを特徴とする小形
駆動機構の形成方法。1. A skeleton structure integrally formed of a substrate having a through hole or a convex portion at a central portion thereof and a cantilever or a doubly supported beam having a structure not in contact with the through hole or the convex portion on the surface of the substrate. In a method for forming a small driving mechanism driven by a coil, a cantilever or a cantilever made of a nickel-iron alloy film constituting a substrate and a substrate composed of silicon and a nickel-iron alloy film or a silicon nitride film constituting the substrate. A method for forming a small driving mechanism, which is manufactured by a sputtering method, an ion etching method, and an anisotropic etching method.
体化構成の作製工程において、犠牲層としてＳｉＯ2 、
ホトレジストおよびアルミニウムのうち何れかを用いる
ことを特徴とする請求項１記載の小形駆動機構の形成方
法。2. In a manufacturing process of an integrated structure of a substrate and a cantilever beam or a cantilever beam, SiO 2 ,
2. The method according to claim 1, wherein one of a photoresist and aluminum is used.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23864892A JP2778879B2 (en) | 1992-09-07 | 1992-09-07 | Forming method of small drive mechanism |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23864892A JP2778879B2 (en) | 1992-09-07 | 1992-09-07 | Forming method of small drive mechanism |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0688253A JPH0688253A (en) | 1994-03-29 |
| JP2778879B2 true JP2778879B2 (en) | 1998-07-23 |
Family
ID=17033260
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP23864892A Expired - Lifetime JP2778879B2 (en) | 1992-09-07 | 1992-09-07 | Forming method of small drive mechanism |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2778879B2 (en) |
-
1992
- 1992-09-07 JP JP23864892A patent/JP2778879B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0688253A (en) | 1994-03-29 |
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