JP2546596C

JP2546596C -

Info

Publication number: JP2546596C
Authority: JP
Original assignee: Hitachi Ltd
Current assignee: Hitachi Ltd
Publication date: 1998-07-30

Description

【発明の詳細な説明】【０００１】【産業上の利用分野】本発明は、プラズマ処理装置に係り、特に、電子サイクロトロン共鳴（以下Ｅ
ＣＲと称す）を利用したプラズマ処理装置に関する。【０００２】【従来の技術】従来のＥＣＲを利用したプラズマ処理装置は、例えば、特開昭５６−１５５５
３５号公報および特開昭５７−７９６２１号公報に記載されており、これを図３
に示している。同図のプラズマ処理装置は、プラズマ生成室１３内においてプラ
ズマ活性種を生じさせ、磁界発生コイル４による発散磁界等で活性種の生成効率
最大領域から充分離れた位置に設置された被処理物１１にプラズマ流をあてて処
理するものであった。【０００３】【発明が解決しようとする課題】上述した従来のプラズマ処理装置は、図示の如くプラズマ生成室１３と比較的
軸長の大きなプラズマ処理室１４とを有しているため、真空容器１の大型化と共
に、この大型化に起因して排気口６および磁界発生コイル４の大型化を招いてい
た。【０００４】この点、本発明者等の実験によれば、ＥＣＲを利用したプラズマ処理において
、その処理特性は、ＥＣＲ位置と被処理物１１との距離とその処理に関わるイオ
ン種の基板入射方向とに依存し、この距離が短いほど、また、イオン入射方向が
基板に垂直になるほど処理特性に優れ、また、ＥＣＲ位置における導入ガス濃度
を高くすると、この位置でマイクロ波３はほとんど吸収されてしまい、被処理物
１１まで到達しないので被処理物１１や支持台９等から反射が消失することがわ
かった。【０００５】しかしながら図３の構成において、被処理物１１をマイクロ波導入窓１０の近
くに位置させて真空容器１の軸長を短縮することも考えられるが、被処理物１１
によるマイクロ波の反射があり、プラズマ処理効率および処理特性を低下させて
しまう。【０００６】本発明の目的は、プラズマ処理特性を低下させることなく真空容器を小型化したプラズマ処理装置を提供するにある。【０００７】【課題を解決するための手段】本発明は上記目的を達成するために、ＥＣＲ面内に反応ガスを導入するととも
に、プラズマにより分解した、もはやマイクロ波の吸収が低くなつた粒子をＥＣ
Ｒ面方向に排気することにより、このＥＣＲ面内での導入ガス濃度の高い状態を
形成し、かつ、基板に向う磁力線方向を、基板面とほぼ同じ高さに設置した磁界
コイルにより基板面に垂直にしたことを特徴とする。【０００８】【作用】本発明のプラズマ処理方式は上述の如きであるから、マイクロ波の吸収が低く
なった粒子を効率よく排気できるため、結果的に導入ガス濃度を高めることがで
きる。このためＥＣＲ面を含んだ領域をマイクロ波の高吸収帯として、マイクロ
波の透過率を著しく低下させることができ、ＥＣＲ位置近傍にマイクロ波導入部
および被処理物を位置させても、プラズマ処理特性を低下させることなくプラズ
マ処理が可能となり、従って、少なくともマイクロ波の伝播方向における真空容
器の長さを従来よりも著しく短縮することができ、小型のプラズマ処理装置が得
られる。【０００９】つまり、成膜やエッチング等のプラズマ処理特性は、プラズマ活性種のうち特
にイオン種の種別，濃度，寿命でほぼ決定され、イオン種の最大生成位置はＥＣ
Ｒ位置であり、ここでイオン種の種別，濃度が決定され、また寿命内で被処理物
に達するか否かはＥＣＲ位置と被処理物の距離で、また、イオンの基板に対する
入射方向は磁力線方向で決定される。更にマイクロ波の伝播は、ＥＣＲ位置およ
びその近傍の分子，原子，イオン等による吸収によって決定される。【００１０】マイクロ波の吸収は分子量が高い粒子程高い。すなわち、プラズマ化により分
解生成したイオンやラジカルよりは導入ガス分子の方が、はるかにマイクロ波を
よく吸収する。また、ＥＣＲ位置でのプラズマ密度は、導入されるガス種及びその分圧で決定される。すなわち、ＥＣＲ位置でのマイクロ波の吸収は、吸収効率
の高い未分解の導入ガス濃度が高いと、そこで一定のプラズマ密度になるまで導
入ガス分子がプラズマ化されることにより生じる。【００１１】しかし、分解して生成したラジカル等、吸収効率の低い粒子濃度が高いとマイ
クロ波の吸収程度は低く、この結果基板まで高パワーのマイクロ波が達すること
になる。従って、最も分解効率の高いＥＣＲ面はもちろんのこと、ＥＣＲ面と基
板までの間に存在するマイクロ波吸収効率の低い粒子を基板に到達する前に極力
排気し、基板までの導入ガス濃度を高い状態とするように、すなわち、上記排気
をＥＣＲ面とほぼ同一面方向、少なくとも、ＥＣＲ面と基板面との間から排気す
るようにすると、基板にマイクロ波が達する程度が低くなり、マイクロ波の反射
を防止することができる。【００１２】なお、基板処理に関与するイオン種は、磁力線により輸送されるので処理効率
を低下させることはない。そして、これらのガス濃度が高いほどマイクロ波の同
領域における透過率が低くなる。【００１３】従って、ＥＣＲ面（ω＝Ｂ・ｅ／ｍマイクロ波の周波数ωで電子の電荷ｅ，
質量ｍを満足する磁束密度Ｂの面）に導入ガスを吹付けたり、この面を含んで同
面あるいはこの面に平行に排気を行うことにより、同面内の導入ガス濃度を高め
ると、この領域においてマイクロ波の高吸収帯が形成され、被処理物へのマイク
ロ波の伝播、あるいは被処理物や支持台からのマイクロ波の反射が抑制されるた
め導入するマイクロ波の実効効力が損われることがない。このため、ＥＣＲ位置
近傍にマイクロ波導入部および被処理物を位置させても、プラズマ処理特性を低
下させることはなくプラズマ処理ができる。【００１４】【実施例】以下本発明の実施例を図面によって説明する。【００１５】図１に示す本発明の一実施例は、直径よりも軸長を小さくした真空容器１を用
い、その上端のマイクロ波導入窓１０から軸方向にマイクロ波３を導入するよう
マイクロ波導波管２を備えている。真空容器１の側方には、反応ガス供給管７，
８および排気口６が形成され、底部の基板支持台９上に被処理物１１を配置して
いる。このような構成の真空容器１の直径は３５０mm，軸長は６２mmで、マイク
ロ波導波管２から供給するマイクロ波３は、３００Ｗで２．４５〔ＧＨｚ〕、波
長１２３mmである。【００１６】反応ガス供給管７，８および排気口６の中心位置と、マイクロ波導入窓１０と
、被処理物１１との位置関係は図２に示されている。同図は、真空容器１の中心
軸上の磁束密度分布を示し、破線は２．４５〔ＧＨｚ〕のマイクロ波３に対し、
ＥＣＲ条件（８７５〔Ｇａｕｓｓ〕）を満す磁束密度値を示している。従って、
ＥＣＲ条件は、マイクロ波導入窓１０からマイクロ波の波長λの１／４である３
１mmの位置で満たされ、同位置は反応ガス供給管７，８からの反応ガスの導入位
置となっている。また、被処理物１１は、マイクロ波導入窓１０から１／２λの
位置にあり、０点はマイクロ波導入窓１０の位置を示している。なお、上述の如
き磁束密度分布は図１の如く真空容器１の外周に設けた磁界発生コイル４、５へ
の電流を制御することにより行なっている。【００１７】基板処理に際して、磁力線が、基板に対して基板端部で斜めに入射すると、成
膜において、段差部でイオン入射部の陰になる所では成膜量が少なくなったり、
膜質が悪くなるといった問題や、エッチングにおいて、基板に垂直にエッチング
が進まないといった問題が発生する。従って、基板処理に際しては、磁力線が基
板にほぼ垂直になるように磁力線を制御する必要がある。【００１８】図３に示した従来技術の場合、基板のはるか上方に磁界発生部があるため、基
板に入る磁力線は、基板中心部では基板に垂直となるが、基板端部では斜めに入
射することになる。【００１９】基板端部でも垂直に入射する磁力線を形成するには、基板処理室の周り全体に
磁界発生コイルを設置することが効果的である。しかし、処理室の外周部全体に
コイルを設置すると、本発明であるＥＣＲ面とほぼ同一平面高さで、低マイクロ
波吸収体粒子の排気を行うことが、コイルが障害となって実現できず、本発明を
完成させることができない。【００２０】しかし、実験によれば、基板にほぼ垂直な磁力線を形成するには、基板とほぼ
同じ高さ位置に磁界発生コイルを設置すれば良く、上記ＥＣＲを発生させる磁界
発生コイル４と５との間隔を、排気口を設置できる程度に空けても良いことが判
った。このため、図１に示す本発明の一実施例は、磁界発生コイル４と５は、真
空容器１の軸方向において排気口６及び反応ガス供給管７，８の両側に分散して
配置している。【００２１】次に、被処理物１１として直径１００mmのシリコンウエハを用い、しかも、そ
の処理面をマイクロ波３の伝播方向に向けて配置し、二酸化けい素（ＳｉＯ₂）
膜を形成する場合について説明する。【００２２】この場合、マイクロ波３は３００Ｗ、２４５〔ＧＨｚ〕、波長１２３mmで、反
応ガス供給管７，８からそれぞれモノシラン（ＳｉＨ₄）を２０ml／min、酸素（
Ｏ₂）を８０ml／minで導入し、反応圧力が１×１０^〜3〔Ｔｏｒｒ〕となるよう
に真空容器１内を排気し、基板端部における磁力線もほぼ基板垂直方向になるよ
うにした。このとき、装置中心軸の磁束密度分布は、図２の条件を満たすように
制御されている。【００２３】このとき、マイクロ波３の反射波は２０Ｗで、平均成膜速度は６０〔nm／min
〕、推積膜の屈折率は１．４６、緩衝フッ酸液（ＨＦ：ＮＨ₄Ｆ＝１：６）によ
るエッチレートは２８０nm／min、ＳｉとＯとの組成比は１.０：２.０であった
。【００２４】この実施例による効果を比較するために、図１で示す位置に排気口６’を形成
してＥＣＲ面での低マイクロ波吸収体を側方から排気せず、すなわち、ＥＣＲ面
でのガス濃度を低下させて成膜したところ、マイクロ波３の反射波は入力３００
Ｗに対し２５０Ｗと著しく増大し、推積速度は上記の実施例の１／１０、また、
推積膜質のエッチレートは上記実施例の３００倍となり、成膜特性が著しく低下
した。【００２５】図４は従来のプラズマ処理装置を、上記実施例の如き観点から分析した真空容
器中心軸上の磁束密度分布を示しており、図２の条件を満たしていないことが判
る。このため、図３の従来技術によるプラズマ処理装置を用いて先の実施例と同
様にＳｉＯ₂膜を形成したところ、マイクロ波３の入力３００Ｗに対して反射波
は１０Ｗであったが、成膜速度は５０〔nm／min〕で、成膜された膜の屈折率は
１．４５、エッチレートは６００〔nm／min〕、ＳｉとＯとの組成比は１．９：
２．０であった。【００２６】この成膜特性と先の本実施例の成膜特性を比較すると判るように、本実施例の
如くＥＣＲ面で発生した低マイクロ波吸収粒子の排気を真空容器側壁から行ない
、ＥＣＲ面での導入ガス濃度を高めることによって、本発明の実施例は、マイク
ロ波３の高吸収帯を形成し、実効効率をほとんど変えることなく、むしろプラズ
マ処理特性を向上させて、真空容器１のマイクロ波伝播方向の軸長を短縮するこ
とができる。【００２７】上述した本発明の実施例において、マイクロ波導入窓１０の位置と、ＥＣＲ位
置と、被処理物１１の位置とのそれぞれの関係は、導入するマイクロ波３の交番
電界強度がほぼ零となる位置にマイクロ波導入窓１０を形成し、ＥＣＲ位置は、
このマイクロ波導入窓１０から（１／４＋ｎ）λ，（ｎ＝０，１，２…）の位置
とし、被処理物は（１／２＋ｎ）λの位置とすると、プラズマを発生させる実効
効率や反射波の減少を期待できる。また、磁界発生コイル４，５による磁界分布は、マイクロ波３の伝播方向に単調減少とすると、マイクロ波３の導入の阻害を
防止することができる。更に、図１に示すように、マイクロ波３の伝播方向の軸
長を直径より小さくした真空容器１を用いると、上述した効果を得る上で実際的
である。【００２８】【発明の効果】以上説明したように本発明では、ＥＣＲ面において発生する低マイクロ波吸収
粒子を排気し、ＥＣＲ面での高マイクロ波吸収粒子である未反応ガスを導入して
ＥＣＲ面での導入ガス濃度の高い状態を形成したため、プラズマ処理特性を低下
させることなく、また、基板にほぼ垂直な磁力線を生成することができるため、
特にマイクロ波伝播方向に真空容器を小型にすることができる。また、２分割し
たコイルの間に排気口が設置されているため、排気効率が良く、排気装置の大型
化を招くことなく装置の小型化を達成することができる。【００２９】また、反応ガス供給管も分割したコイルの間の空間を利用して真空容器に接続
されているため、ガス供給系の単純化を図ることができる。Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma processing apparatus, and more particularly, to an electron cyclotron resonance (hereinafter referred to as E).
(Hereinafter referred to as CR). 2. Description of the Related Art A conventional plasma processing apparatus using ECR is disclosed in, for example, Japanese Patent Application Laid-Open No. 56-1555.
No. 35 and JP-A-57-79621, which are shown in FIG.
Is shown in The plasma processing apparatus shown in FIG. 1 generates a plasma active species in a plasma generation chamber 13 and uses a divergent magnetic field generated by a magnetic field generating coil 4 or the like to place an object 11 placed at a position sufficiently distant from the active species generation efficiency maximum region. And a plasma flow. [0003] The conventional plasma processing apparatus described above has a plasma generation chamber 13 and a plasma processing chamber 14 having a relatively large axial length as shown in the figure, and therefore, the vacuum vessel 1 With the increase in size, the exhaust port 6 and the magnetic field generating coil 4 have also increased due to the increase in size. In this regard, according to experiments performed by the present inventors, in plasma processing using ECR, the processing characteristics include the distance between the ECR position and the workpiece 11 and the direction of incidence of the ion species involved in the processing on the substrate. The shorter the distance and the more perpendicular the ion incidence direction to the substrate, the better the processing characteristics. If the concentration of the introduced gas at the ECR position is increased, the microwave 3 is almost absorbed at this position. As a result, since the light does not reach the object to be processed 11, the reflection from the object to be processed 11, the support 9 and the like disappears. However, in the configuration shown in FIG. 3, it is conceivable to reduce the axial length of the vacuum vessel 1 by positioning the object 11 near the microwave introduction window 10.
And the plasma processing efficiency and processing characteristics are degraded. An object of the present invention is to provide a plasma processing apparatus in which a vacuum vessel is reduced in size without deteriorating plasma processing characteristics. Means for Solving the Problems In order to achieve the above object, the present invention introduces a reaction gas into an ECR surface, and simultaneously removes particles decomposed by plasma and having low microwave absorption. EC
By evacuating in the direction of the R plane, a state where the concentration of the introduced gas is high in the ECR plane is formed, and the direction of the line of magnetic force facing the substrate is changed to the surface of the substrate by a magnetic field coil installed at substantially the same height as the surface of the substrate. It is characterized by being vertical. Since the plasma processing method of the present invention is as described above, particles having reduced microwave absorption can be efficiently exhausted, and as a result, the concentration of the introduced gas can be increased. For this reason, the region including the ECR surface is set as a high absorption band for microwaves, so that the microwave transmittance can be remarkably reduced. Even if the microwave introduction part and the object to be processed are located near the ECR position, the plasma processing is performed. The plasma processing can be performed without deteriorating the characteristics. Therefore, at least the length of the vacuum vessel in the microwave propagation direction can be significantly reduced as compared with the conventional case, and a compact plasma processing apparatus can be obtained. That is, the characteristics of plasma processing such as film formation and etching are almost determined by the type, concentration, and lifetime of the ion species among the plasma active species, and the maximum generation position of the ion species is determined by EC.
The R position, where the type and concentration of the ion species are determined. Whether the ion reaches the object within the life is determined by the distance between the ECR position and the object, and the direction of incidence of the ions on the substrate is the line of magnetic force. Determined by the direction. Further, the propagation of microwaves is determined by absorption by molecules, atoms, ions, and the like at and near the ECR position. [0010] Microwave absorption is higher for higher molecular weight particles. In other words, the introduced gas molecules absorb microwaves much better than ions or radicals generated by decomposition by plasma. The plasma density at the ECR position is determined by the type of gas to be introduced and its partial pressure. That is, the absorption of microwaves at the ECR position occurs when the concentration of the undecomposed introduced gas having high absorption efficiency is high, and the introduced gas molecules are converted into plasma until a constant plasma density is obtained there. However, if the concentration of particles having low absorption efficiency, such as radicals generated by decomposition, is high, the degree of microwave absorption is low, and as a result, high-power microwaves reach the substrate. Therefore, particles having low microwave absorption efficiency existing between the ECR surface and the substrate as well as the ECR surface having the highest decomposition efficiency are exhausted as much as possible before reaching the substrate, and the concentration of the introduced gas to the substrate is increased. If the gas is exhausted from the direction substantially the same plane as the ECR surface, that is, at least between the ECR surface and the substrate surface, the extent to which the microwave reaches the substrate is reduced. Reflection can be prevented. Note that ion species involved in substrate processing are transported by lines of magnetic force, and therefore do not reduce processing efficiency. The higher the gas concentration, the lower the microwave transmittance in the same region. Therefore, the ECR surface (ω = B · e / m, the electron charge e,
When the introduced gas is blown onto the surface of the magnetic flux density B that satisfies the mass m, or the surface is exhausted including or in parallel with the surface, the concentration of the introduced gas is increased. A high absorption band of microwaves is formed in the region, and the propagation of the microwave to the object to be processed or the reflection of the microwave from the object to be processed and the support base are suppressed, so that the effective efficiency of the introduced microwave is impaired. Nothing. For this reason, even if the microwave introduction part and the object to be processed are located near the ECR position, the plasma processing can be performed without lowering the plasma processing characteristics. Embodiments of the present invention will be described below with reference to the drawings. An embodiment of the present invention shown in FIG. 1 uses a vacuum vessel 1 having an axial length smaller than a diameter, and introduces microwaves 3 in an axial direction from a microwave introduction window 10 at an upper end thereof. A wave tube 2 is provided. At the side of the vacuum vessel 1, a reaction gas supply pipe 7,
8 and an exhaust port 6 are formed, and an object to be processed 11 is disposed on a substrate support 9 at the bottom. The diameter of the vacuum vessel 1 having such a configuration is 350 mm, the axial length is 62 mm, and the microwave 3 supplied from the microwave waveguide 2 is 2.45 [GHz] at 300 W and the wavelength is 123 mm. FIG. 2 shows the positional relationship between the center positions of the reaction gas supply pipes 7 and 8 and the exhaust port 6, the microwave introduction window 10, and the object 11. The figure shows the magnetic flux density distribution on the central axis of the vacuum vessel 1, and the broken line indicates the microwave 3 of 2.45 [GHz].
The magnetic flux density values satisfying the ECR condition (875 [Gauss]) are shown. Therefore,
The ECR condition is １／ of the wavelength λ of the microwave from the microwave introduction window 10.
It is filled at a position of 1 mm, which is a position for introducing the reaction gas from the reaction gas supply pipes 7 and 8. The object 11 is located at a position １／ λ from the microwave introduction window 10, and the point 0 indicates the position of the microwave introduction window 10. Note that the magnetic flux density distribution as described above is performed by controlling the current to the magnetic field generating coils 4 and 5 provided on the outer periphery of the vacuum vessel 1 as shown in FIG. In the processing of the substrate, if the magnetic field lines are obliquely incident on the substrate at the edge of the substrate, the amount of film formation may be reduced in the film formation where the step is in the shadow of the ion incident portion.
The problem that the film quality is deteriorated and the problem that the etching does not proceed perpendicularly to the substrate occur in the etching. Therefore, when processing the substrate, it is necessary to control the magnetic field lines so that the magnetic field lines are substantially perpendicular to the substrate. In the case of the prior art shown in FIG. 3, since the magnetic field generating portion is located far above the substrate, the lines of magnetic force entering the substrate are perpendicular to the substrate at the center of the substrate, but obliquely enter at the edge of the substrate. Will be. In order to form lines of magnetic force that are perpendicularly incident on the edge of the substrate, it is effective to install a magnetic field generating coil around the entire substrate processing chamber. However, when the coil is installed on the entire outer peripheral portion of the processing chamber, it is not possible to exhaust the low microwave absorber particles at almost the same height as the ECR surface according to the present invention because the coil becomes an obstacle. However, the present invention cannot be completed. However, according to experiments, in order to form lines of magnetic force that are substantially perpendicular to the substrate, the magnetic field generating coils may be installed at substantially the same height as the substrate, and the magnetic field generating coils 4 and 5 that generate the ECR are used. It has been found that the space between them may be made large enough to install the exhaust port. For this reason, in one embodiment of the present invention shown in FIG. 1, the magnetic field generating coils 4 and 5 are arranged in both sides of the exhaust port 6 and the reaction gas supply pipes 7 and 8 in the axial direction of the vacuum vessel 1. I have. Next, a silicon wafer having a diameter of 100 mm is used as the object to be processed 11, and its processed surface is arranged in the propagation direction of the microwave 3, and silicon dioxide (SiO ₂ ) is used.
The case of forming a film will be described. In this case, the microwave 3 is 300 W, 245 [GHz], the wavelength is 123 mm, monosilane (SiH ₄ ) is supplied from the reaction gas supply pipes 7 and 8 at 20 ml / min and oxygen (
O ₂ ) was introduced at a rate of 80 ml / min, and the inside of the vacuum vessel 1 was evacuated so that the reaction pressure became 1 × 10 ^-3 [Torr], so that the lines of magnetic force at the edge of the substrate were also almost perpendicular to the substrate. At this time, the magnetic flux density distribution on the central axis of the device is controlled so as to satisfy the condition of FIG. At this time, the reflected wave of the microwave 3 is 20 W, and the average film forming speed is 60 [nm / min.
], The refractive index of the deposited film is 1.46, the etch rate by buffered hydrofluoric acid solution (HF: NH ₄ F = 1: 6) is 280 nm / min, and the composition ratio of Si and O is 1.0: 2. It was 0. In order to compare the effects of this embodiment, an exhaust port 6 ′ is formed at the position shown in FIG. 1 so that the low microwave absorber on the ECR surface is not exhausted from the side, that is, on the ECR surface. When the film was formed with the gas concentration lowered, the reflected wave of the microwave 3
W is remarkably increased to 250 W with respect to W, and the deposition speed is 1/10 of the above embodiment, and
The etch rate of the deposited film quality was 300 times that of the above example, and the film formation characteristics were significantly reduced. FIG. 4 shows the magnetic flux density distribution on the central axis of the vacuum vessel obtained by analyzing the conventional plasma processing apparatus from the viewpoint of the above embodiment, and it can be seen that the condition of FIG. 2 is not satisfied. Therefore, when the SiO ₂ film was formed using the plasma processing apparatus according to the prior art of FIG. 3 in the same manner as in the previous embodiment, the reflected wave was 10 W with respect to the input 300 W of the microwave 3. The speed was 50 [nm / min], the refractive index of the formed film was 1.45, the etch rate was 600 [nm / min], and the composition ratio of Si and O was 1.9:
2.0. As can be seen from a comparison between the film forming characteristics and the film forming characteristics of the present embodiment, the low microwave absorbing particles generated on the ECR surface are evacuated from the side wall of the vacuum vessel as in the present embodiment, and the ECR surface is removed. By increasing the concentration of the introduced gas in the vacuum chamber, the embodiment of the present invention forms a high absorption band of the microwave 3 and improves the plasma processing characteristics without substantially changing the effective efficiency. The axial length in the wave propagation direction can be reduced. In the above-described embodiment of the present invention, the relationship between the position of the microwave introduction window 10, the ECR position, and the position of the workpiece 11 is such that the alternating electric field intensity of the microwave 3 to be introduced is almost zero. A microwave introduction window 10 is formed at a position where
If the microwave introduction window 10 is located at (１／ + n) λ, (n = 0, 1, 2,...) And the object is located at (１／ + n) λ, the effective efficiency of generating plasma and the A reduction in reflected waves can be expected. Further, if the magnetic field distribution by the magnetic field generating coils 4 and 5 is monotonously decreased in the propagation direction of the microwave 3, it is possible to prevent the introduction of the microwave 3 from being hindered. Furthermore, as shown in FIG. 1, it is practical to obtain the above-described effects by using a vacuum vessel 1 having an axis length in the propagation direction of the microwave 3 smaller than the diameter. As described above, according to the present invention, the low microwave absorbing particles generated on the ECR surface are exhausted, and the unreacted gas, which is the high microwave absorbing particles, is introduced on the ECR surface to introduce the ECR. Since the state of high introduced gas concentration on the surface was formed, without deteriorating the plasma processing characteristics, and because magnetic lines of force almost perpendicular to the substrate can be generated,
In particular, the size of the vacuum container can be reduced in the microwave propagation direction. Further, since the exhaust port is provided between the two divided coils, the exhaust efficiency is high, and the size of the exhaust device can be reduced without increasing the size of the exhaust device. Further, since the reaction gas supply pipe is also connected to the vacuum vessel using the space between the divided coils, the gas supply system can be simplified.

【図面の簡単な説明】【図１】本発明のプラズマ処理方式を適用したプラズマ処理装置の縦断面図である。【図２】図１の真空容器中心軸上の磁束密度分布を示す図である。【図３】従来技術によるプラズマ処理装置の縦断面図である。【図４】図３の真空容器中心軸上の磁束密度分布を示す図である。【符号の説明】１真空容器３マイクロ波４，５磁界発生コイル６排気口７，８反応ガス供給管１０マイクロ波導入窓１１被処理物[Brief description of the drawings] FIG. It is a longitudinal section of a plasma processing device to which the plasma processing system of the present invention is applied. FIG. 2 FIG. 2 is a diagram illustrating a magnetic flux density distribution on a central axis of the vacuum vessel in FIG. 1. FIG. 3 It is a longitudinal section of a plasma processing device by a conventional technology. FIG. 4 FIG. 4 is a diagram illustrating a magnetic flux density distribution on a central axis of the vacuum vessel in FIG. 3. [Explanation of symbols] 1 vacuum container 3 Microwave 4,5 Magnetic field generating coil 6 exhaust port 7,8 Reaction gas supply pipe 10 Microwave introduction window 11 Workpiece

Claims

[Claims] 1. A vacuum container in which an object to be processed is installed, a microwave introduction window provided in the vacuum container, a gas introduction port provided in the vacuum container, a gas exhaust port provided in the vacuum container, and disposed outside the vacuum container. Magnetic field generating means for generating a magnetic field sufficient to generate plasma by electron cyclotron resonance in the vacuum vessel, wherein the electron cyclotron resonance surface for generating plasma by electron cyclotron resonance has a (N + ／) times the wavelength of (n = 0,1)
, 2...). 2. A vacuum container in which an object to be processed is installed, a microwave introduction window provided in the vacuum container, a gas introduction port provided in the vacuum container, a gas exhaust port provided in the vacuum container, and disposed outside the vacuum container. And two magnetic field generating means for generating a magnetic field sufficient to generate plasma by electron cyclotron resonance in the vacuum vessel, wherein the two magnetic field generating means are located on the microwave introduction window side and on the object side. And the gas exhaust port and the plasma generation position are located between the two magnetic field generating means, and the position of the gas exhaust port is substantially flush with the electron cyclotron resonance surface. A plasma processing apparatus characterized by the above-mentioned. 3. 3. The plasma processing apparatus according to claim 2, wherein the vacuum vessel has an axial length in a microwave propagation direction smaller than a diameter of the vacuum vessel. 4. 3. The plasma processing apparatus according to claim 2, wherein said gas inlet is located between said two magnetic field generating means.