JPH05195258A - Plasma etching device - Google Patents
Plasma etching deviceInfo
- Publication number
- JPH05195258A JPH05195258A JP616492A JP616492A JPH05195258A JP H05195258 A JPH05195258 A JP H05195258A JP 616492 A JP616492 A JP 616492A JP 616492 A JP616492 A JP 616492A JP H05195258 A JPH05195258 A JP H05195258A
- Authority
- JP
- Japan
- Prior art keywords
- wire electrode
- plasma
- workpiece
- work
- plasma etching
- 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.)
- Pending
Links
Landscapes
- Electrical Discharge Machining, Electrochemical Machining, And Combined Machining (AREA)
- ing And Chemical Polishing (AREA)
- Drying Of Semiconductors (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明はプラズマエッチング装置
に関する。FIELD OF THE INVENTION The present invention relates to a plasma etching apparatus.
【０００２】[0002]
【従来の技術】プラズマ中で作られる弗素原子や塩素原
子の反応性ラジカル種を被加工体に吹きつけ、被加工体
の原子と上記反応性ラジカル種との反応によって生じる
揮発性分子を被加工体の表面近くから運び去ることによ
って被加工体を蝕刻するプラズマエッチング装置は公知
である。然しながら、従来のプラズマエッチング装置に
よるエッチングのアスペクト比は最大でも300 程度であ
って、被加工体の切断や深い溝の加工等を高精度に行な
うには不充分であった。2. Description of the Prior Art Reactive radical species such as fluorine and chlorine atoms produced in plasma are blown onto a workpiece to process volatile molecules generated by the reaction between the atoms of the workpiece and the reactive radical species. Plasma etching devices are known for etching a work piece by carrying it away from near the surface of the body. However, the aspect ratio of etching by the conventional plasma etching apparatus is about 300 at the maximum, which is insufficient for highly accurate cutting of the work piece or processing of deep grooves.
【０００３】[0003]
【発明が解決しようとする課題】本発明は、上記の問題
点を解決するためなされたものであり、その目的とする
ところは、エッチングのアスペクト比を1000〜50000 程
度に高め、被加工体の切断や深い溝加工等を高精度に行
ない得るプラズマエッチング装置を提供することにあ
る。SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and its purpose is to increase the aspect ratio of etching to about 1000 to 50,000 and An object of the present invention is to provide a plasma etching apparatus that can perform cutting and deep groove processing with high accuracy.
【０００４】[0004]
【課題を解決するための手段】上記の目的は、減圧気体
中で被加工体とワイヤ電極を対向させ、ワイヤ電極をそ
の軸方向に移動させながら、被加工体とワイヤ電極間に
放電プラズマを発生させ被加工体のエッチングを行なう
よう構成したことを特徴とするプラズマエッチング装置
によって達成できる。Means for Solving the Problems The above-mentioned object is to make a discharge plasma between a workpiece and a wire electrode while facing the workpiece and the wire electrode in a depressurized gas and moving the wire electrode in the axial direction thereof. This can be achieved by a plasma etching apparatus characterized in that it is configured to generate and etch a workpiece.
【０００５】その場合、被加工体とワイヤ電極が対向し
た放電プラズマ発生領域にプラズマガスを噴射し、当該
領域の圧力を周囲より高くするガス供給装置を設けるこ
とが推奨され、そのプラズマガスとしてはハロゲン混合
ガスを用いることが推奨される。又、被加工体とワイヤ
電極間の加工送りをＮＣ装置により制御するようにする
ことが推奨される。更に又、被加工体を一極として加工
を行なったり、直流に高周波を重畳した偏倚電圧を印加
して加工を行なうことも推奨される。たとき、 100Ｖ／
cmで電子作用が減少し、加熱作用が約80％となった。In this case, it is recommended to provide a gas supply device for injecting a plasma gas into a discharge plasma generation region where the workpiece and the wire electrode face each other and increasing the pressure in the region higher than the surroundings. It is recommended to use a halogen gas mixture. Further, it is recommended that the machining feed between the workpiece and the wire electrode be controlled by the NC device. Furthermore, it is also recommended that the work piece be processed with one pole as the work piece, or that a bias voltage in which a high frequency wave is superimposed on a direct current be applied to perform the work piece. 100V /
The electron action decreased in cm, and the heating action became about 80%.
【０００６】[0006]
【作用】上記の如き構成であると、細いワイヤ電極に沿
ってプラズマが形成されるので、エッチングのアスペク
ト比は容易に1000〜50000 程度にまで高められ、被加工
体にワイヤ電極を切り込ませながら深い溝の加工や切断
等を高精度で行ない得るものである。また、プラズマ発
生領域にハロゲン混合ガス等のプラズマガスを噴射し、
当該領域の圧力を周囲より高くすることによってプラズ
マの集束がなされ、より高精度の加工が行なわれるもの
である。更にまた、被加工体とワイヤ電極間の加工送り
をＮＣ装置により制御することにより、長時間の無人加
工が可能となる。又、直流に高周波を重畳した偏倚電圧
を印加して加工を行なうことにより、電子作用が減少
し、加熱作用を抑制することができる。With the above structure, plasma is formed along the thin wire electrode, so that the aspect ratio of etching can be easily increased to about 1000 to 50,000, and the wire electrode is not cut into the work piece. However, deep grooves can be processed and cut with high precision. Also, a plasma gas such as a halogen mixed gas is injected into the plasma generation region,
By making the pressure in the region higher than that of the surroundings, the plasma is focused, and more precise processing is performed. Furthermore, by controlling the machining feed between the workpiece and the wire electrode by the NC device, unmanned machining for a long time becomes possible. Further, by applying a bias voltage in which a high frequency is superposed on direct current to perform processing, the electron action is reduced and the heating action can be suppressed.
【０００７】[0007]
【実施例】以下、図面を参照しつゝ本発明を具体的に説
明する。図１は、本発明に係るプラズマエッチング装置
の一実施例を示す説明図であり、図中、１は処理室、２
は処理室内を減圧状態にする真空ポンプ、３はワイヤ電
極、４はワイヤ電極供給ドラム、５はブレーキ装置、６
はガイドローラ、７及び８は電極位置決めガイド、９は
ワイヤ電極送りローラ、10はローラ９を駆動するモー
タ、11はピンチローラ、12はワイヤ電極回収ドラム、13
は被加工体、14は被加工体13を搭載したＸ−Ｙクロスス
ライドテーブル（図では省略）のＸ軸方向駆動モータ、
15はＹ軸方向駆動モータ、16は被加工体13を回転させる
モータ、17はプラズマ発生用電源、18はワイヤ電極への
通電ピン、19は被加工体への通電ピン、20は前記モータ
14，15，16の作動を制御することにより被加工体13に対
する加工送りを制御するＮＣ装置、21はノズル22，23，
24を通じてワイヤ電極のプラズマ発生領域にプラズマガ
スを噴出供給するプラズマガス供給装置、25は上記プラ
ズマ発生用電源17やＮＣ装置20及びプラズマガス供給装
置21等の作動を制御することにより装置全体の運転制御
を行なう制御装置である。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to the drawings. FIG. 1 is an explanatory view showing an embodiment of the plasma etching apparatus according to the present invention, in which 1 is a processing chamber and 2 is a processing chamber.
Is a vacuum pump for reducing the pressure in the processing chamber, 3 is a wire electrode, 4 is a wire electrode supply drum, 5 is a brake device, 6
Is a guide roller, 7 and 8 are electrode positioning guides, 9 is a wire electrode feed roller, 10 is a motor for driving the roller 9, 11 is a pinch roller, 12 is a wire electrode collecting drum, 13
Is a workpiece, 14 is an X-axis direction drive motor of an XY cross slide table (not shown) on which the workpiece 13 is mounted,
Reference numeral 15 is a Y-axis direction driving motor, 16 is a motor for rotating the workpiece 13, 17 is a power source for plasma generation, 18 is an energizing pin for the wire electrode, 19 is an energizing pin for the workpiece, and 20 is the motor.
An NC device for controlling the machining feed to the workpiece 13 by controlling the operations of 14, 15, 16 and 21 are nozzles 22, 23,
A plasma gas supply device for supplying and ejecting a plasma gas to the plasma generation region of the wire electrode through 24, and an operation of the entire device by controlling the operations of the plasma generation power supply 17, the NC device 20, the plasma gas supply device 21, etc. It is a control device for controlling.
【０００８】加工中、処理室１内は真空ポンプ２により
10-5〜10-9Torr程度に減圧され、被加工体13は僅かな間
隙を保ってワイヤ電極３に対向せしめられ、プラズマ発
生用電源17から加えられる電圧により被加工体とワイヤ
電極の間にプラズマが発生して被加工体のエッチング加
工が行なわれる。このとき、ワイヤ電極を停止したまゝ
で加工を行なうと、ワイヤ電極が加熱したりスパッタを
生じて断線するので、ワイヤ電極３は加工中常時その軸
方向に５〜50ｍ／ｓ程度の高速度で移動させるようにな
っている。即ち、モータ10を駆動して送りローラ９を高
速回転させることによりワイヤ電極供給ドラム４からワ
イヤ電極３を連続的に引き出し、回収ドラム12に巻き取
るものであるが、供給ドラム４から引き出されたワイヤ
電極３は、ブレーキ装置５により所定の張力を付与さ
れ、ガイドローラ６を経て電極位置決めガイド７及び８
間に直線状に張架され、この張架部分において被加工体
13と近接して対向せしめられ、被加工体のプラズマエッ
チングを行なうようになっている。ワイヤ電極３は、放
電により被加工体を汚染しないように、一般的にはＭ
ｏ、Ｗ等の耐熱性の材質のものが好適に利用される。During processing, a vacuum pump 2 is used in the processing chamber 1.
The pressure is reduced to about 10 -5 to 10 -9 Torr, the work piece 13 is made to face the wire electrode 3 with a slight gap, and the voltage applied from the plasma generating power supply 17 causes a gap between the work piece and the wire electrode. Plasma is generated in the substrate and the workpiece is etched. At this time, if the wire electrode is machined while it is stopped, the wire electrode is heated or spatters and is disconnected. Therefore, the wire electrode 3 is constantly moved in the axial direction at a high speed of about 5 to 50 m / s during machining. It is designed to be moved with. That is, the motor 10 is driven to rotate the feed roller 9 at a high speed to continuously pull out the wire electrode 3 from the wire electrode supply drum 4 and wind the wire electrode 3 around the recovery drum 12, but the wire electrode 3 is pulled out from the supply drum 4. The wire electrode 3 is given a predetermined tension by the brake device 5, passes through the guide roller 6, and the electrode positioning guides 7 and 8 are provided.
It is stretched in a straight line between the workpieces and
It is made to face to and close to 13 and is adapted to perform plasma etching of the workpiece. The wire electrode 3 is generally M so as not to contaminate the work piece by electric discharge.
Materials made of heat-resistant materials such as o and W are preferably used.
【０００９】図示した実施例において、被加工体13は円
柱状のＳｉの単結晶であり、これをモータ16により軸中
心に回転させながら、その外周部分から中心へ向けてワ
イヤ電極３で切り込んで切断加工する状態を示してい
る。被加工体13の加工時の位置決め及び加工送りは、モ
ータ14及び15によってＸ−Ｙ軸方向に駆動されるクロス
スライドテーブル（図示せず）によって行なわれ、その
駆動はＮＣ装置20によって制御されるようになってい
る。In the illustrated embodiment, the work piece 13 is a cylindrical single crystal of Si, which is rotated by the motor 16 about the axis and cut by the wire electrode 3 from the outer peripheral portion toward the center. The state which carries out cutting processing is shown. Positioning and machining feed of the workpiece 13 during machining are performed by a cross slide table (not shown) driven by the motors 14 and 15 in the XY axis directions, and the drive is controlled by the NC device 20. It is like this.
【００１０】而して、ワイヤ電極３と被加工体13が対向
して電源17からの電圧により放電プラズマが形成される
領域には、プラズマガス供給装置21から小型のノズル2
2，23及び24を通じてハロゲン含有ガスが供給されるよ
うになっている。このガスは、プラズマ形成領域の圧力
を周囲の圧力より増加させてプラズマを集中させる作用
を有し、処理室１内の圧力を前記の如く10-5〜10-9Torr
程度に減圧した場合おいて、プラズマ形成領域の圧力は
１〜50Torr程度に保つようにする。In the region where the wire electrode 3 and the work piece 13 face each other and discharge plasma is formed by the voltage from the power supply 17, the small nozzle 2 from the plasma gas supply device 21 is provided.
The halogen-containing gas is supplied through 2, 23 and 24. This gas has a function of increasing the pressure in the plasma formation region above the ambient pressure to concentrate the plasma, and the pressure in the processing chamber 1 is 10 −5 to 10 −9 Torr as described above.
When the pressure is reduced to a certain level, the pressure in the plasma formation region is maintained at about 1 to 50 Torr.
【００１１】上記の如く構成された装置を用いて、例え
ばＳｉの円柱状単結晶８”のものを50rpm で回転させな
がら、線径 0.1mmφのＭｏ（モリブデン）材から成るワ
イヤ電極に 180ｇの張力を加えて速度10ｍ／ｓで移動さ
せながら加工した場合、112分で切断することができ
た。この場合、加工領域部分で発生する被加工体の原子
を含むガスは加工溝を通じて排出するようにするもので
あり、前記ノズル22，23及び24を通じてＳＦ6 ＋Ｏ2 ＋
Ｎ2 （混合比２：１：１）の混合ガスを加工溝内の圧力
が15Ｐa 〜30Ｐa になるように噴射供給しながら加工溝
内のガス交換を行ない、ワイヤ電極の周囲に出力 800Ｗ
で 13.56ＭＨのプラズマを発生させて加工を行なった。
一般に、ワイヤ電極の移動速度が速い方が良好な加工が
行なわれ、またプラズマ発生用電圧に400 Ｖ程度のバイ
アス電圧を加えておくことにより加工速度が10〜30％程
度向上することが判った。また、直流に高周波を重畳し
た偏倚電圧を印加したとき、 100Ｖ／cmで電子作用が減
少し、加熱作用が約80％となった。Using the apparatus configured as described above, for example, while rotating a cylindrical single crystal of Si 8 ″ at 50 rpm, a wire electrode made of Mo (molybdenum) material having a wire diameter of 0.1 mmφ is applied with a tension of 180 g. In addition, when processing was performed while moving at a speed of 10 m / s, it was possible to cut in 112 minutes.In this case, the gas containing the atoms of the workpiece generated in the processing area was discharged through the processing groove. SF 6 + O 2 + through the nozzles 22, 23 and 24
The gas in the machining groove is exchanged while the mixed gas of N 2 (mixing ratio 2: 1: 1) is injected and supplied so that the pressure in the machining groove becomes 15 Pa to 30 Pa, and the output is 800 W around the wire electrode.
Then, processing was performed by generating 13.56 MH plasma.
In general, it has been found that the higher the moving speed of the wire electrode is, the better the processing is performed, and that the processing speed is improved by about 10 to 30% by applying a bias voltage of about 400 V to the plasma generating voltage. .. Also, when a bias voltage in which a high frequency was superimposed on DC was applied, the electron action decreased at 100 V / cm, and the heating action became about 80%.
【００１２】[0012]
【発明の効果】本発明は叙上の如く構成されるから、本
発明によるときは、細いワイヤ電極に沿ってプラズマが
形成されるので、エッチングのアスペクト比を容易に10
00〜50000 程度にまで高めることができ、被加工体にワ
イヤ電極を切り込ませながら深い溝の加工や切断等を高
精度で行ない得るものである。また、プラズマ発生領域
にハロゲン混合ガス等のプラズマガスを噴射し、当該領
域の圧力を周囲より高くすることによってプラズマの集
束がなされ、より高精度の加工が行なわれるものであ
る。更にまた、被加工体とワイヤ電極間の加工送りをＮ
Ｃ装置により制御することにより、長時間の無人加工が
可能となる。Since the present invention is constructed as described above, according to the present invention, plasma is formed along the thin wire electrode, so that the aspect ratio of etching can be easily controlled.
It can be increased up to about 00 to 50,000, and it is possible to process and cut deep grooves with high precision while cutting the wire electrode into the work piece. Further, by injecting a plasma gas such as a halogen mixed gas into the plasma generation region and making the pressure in the region higher than that of the surroundings, the plasma is focused, and more accurate processing is performed. Furthermore, the machining feed between the workpiece and the wire electrode is N
By controlling with the C device, unmanned processing for a long time becomes possible.
【図１】本発明に係るプラズマエッチング装置の一実施
例を示す説明図である。FIG. 1 is an explanatory view showing an embodiment of a plasma etching apparatus according to the present invention.
1 処理室 2 真空ポンプ 3 ワイヤ電極 4 ワイヤ電極供給ドラム 5 ブレーキ装置 6 ガイドローラ 7,8 電極位置決めガイド 9 ワイヤ電極送りローラ 10 モータ 11 ピンチローラ 12 ワイヤ電極回収ドラム 13 被加工体 14 Ｘ軸方向駆動モータ 15 Ｙ軸方向駆動モータ 16 被加工体回転用モータ 17 プラズマ発生用電源 18,19 通電ピン 20 ＮＣ装置 21 プラズマガス供給装置 22,23,24 ノズル 25 制御装置 1 processing chamber 2 vacuum pump 3 wire electrode 4 wire electrode supply drum 5 brake device 6 guide roller 7,8 electrode positioning guide 9 wire electrode feed roller 10 motor 11 pinch roller 12 wire electrode recovery drum 13 workpiece 14 X-axis drive Motor 15 Y-axis drive motor 16 Motor for rotating workpiece 17 Power source for plasma generation 18,19 Energizing pin 20 NC device 21 Plasma gas supply device 22,23,24 Nozzle 25 Control device
Claims (6)
(3) を対向させ、ワイヤ電極(3) をその軸方向に移動さ
せながら、被加工体(13)とワイヤ電極(3) 間に放電プラ
ズマを発生させ被加工体(13)のエッチングを行なうよう
構成したことを特徴とするプラズマエッチング装置。1. A workpiece (13) and a wire electrode in a reduced pressure gas.
(3) face each other, and while moving the wire electrode (3) in the axial direction, discharge plasma is generated between the workpiece (13) and the wire electrode (3) to etch the workpiece (13). A plasma etching apparatus having the above structure.
放電プラズマ発生領域にプラズマガスを噴射し、当該領
域の圧力を周囲より高くするガス供給装置(21 〜24) を
設けた請求項１に記載のプラズマエッチング装置。2. A gas supply device (21 to 24) for injecting a plasma gas into a discharge plasma generation region in which a workpiece (13) and a wire electrode (3) face each other and increasing the pressure of the region higher than the surroundings. The plasma etching apparatus according to claim 1.
射する請求項２に記載のプラズマエッチング装置。3. The plasma etching apparatus according to claim 2, wherein a halogen mixed gas is injected as the plasma gas.
りを制御するＮＣ装置(20)を設けた請求項１ないし３の
うちいずれか一に記載のプラズマエッチング装置。4. The plasma etching apparatus according to claim 1, further comprising an NC device (20) for controlling a machining feed between the workpiece (13) and the wire electrode (3).
求項１ないし４のうちいずれか一に記載のプラズマエッ
チング装置。5. The plasma etching apparatus according to claim 1, wherein the workpiece (13) is used as a pole for processing.
る請求項１ないし５のうちいずれか一に記載のプラズマ
エッチング装置。6. The plasma etching apparatus according to claim 1, wherein a bias voltage in which a high frequency is superimposed on a direct current is applied.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP616492A JPH05195258A (en) | 1992-01-17 | 1992-01-17 | Plasma etching device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP616492A JPH05195258A (en) | 1992-01-17 | 1992-01-17 | Plasma etching device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH05195258A true JPH05195258A (en) | 1993-08-03 |
Family
ID=11630894
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP616492A Pending JPH05195258A (en) | 1992-01-17 | 1992-01-17 | Plasma etching device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH05195258A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0781618A4 (en) * | 1995-07-12 | 2000-12-20 | Japan Res Dev Corp | Highly efficient processing method based on high density radical reaction and using rotary electrode, apparatus therefor and rotating electrode used therefor |
| JP2006022393A (en) * | 2004-07-09 | 2006-01-26 | Yuzo Mori | Ultraprecision processing device |
| JP2009054779A (en) * | 2007-08-27 | 2009-03-12 | Toyo Advanced Technologies Co Ltd | Plasma processing apparatus and plasm processing method |
| JP2009054777A (en) * | 2007-08-27 | 2009-03-12 | Toyo Advanced Technologies Co Ltd | Plasma processing apparatus and plasm processing method |
| JP2009054778A (en) * | 2007-08-27 | 2009-03-12 | Toyo Advanced Technologies Co Ltd | Plasma processing apparatus and plasm processing method |
-
1992
- 1992-01-17 JP JP616492A patent/JPH05195258A/en active Pending
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0781618A4 (en) * | 1995-07-12 | 2000-12-20 | Japan Res Dev Corp | Highly efficient processing method based on high density radical reaction and using rotary electrode, apparatus therefor and rotating electrode used therefor |
| JP2006022393A (en) * | 2004-07-09 | 2006-01-26 | Yuzo Mori | Ultraprecision processing device |
| JP4595413B2 (en) * | 2004-07-09 | 2010-12-08 | 森 勇蔵 | Ultra-precision processing equipment |
| JP2009054779A (en) * | 2007-08-27 | 2009-03-12 | Toyo Advanced Technologies Co Ltd | Plasma processing apparatus and plasm processing method |
| JP2009054777A (en) * | 2007-08-27 | 2009-03-12 | Toyo Advanced Technologies Co Ltd | Plasma processing apparatus and plasm processing method |
| JP2009054778A (en) * | 2007-08-27 | 2009-03-12 | Toyo Advanced Technologies Co Ltd | Plasma processing apparatus and plasm processing method |
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