JP2014038874A - Plasma-induced cvd method - Google Patents

Plasma-induced cvd method Download PDF

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JP2014038874A
JP2014038874A JP2010250138A JP2010250138A JP2014038874A JP 2014038874 A JP2014038874 A JP 2014038874A JP 2010250138 A JP2010250138 A JP 2010250138A JP 2010250138 A JP2010250138 A JP 2010250138A JP 2014038874 A JP2014038874 A JP 2014038874A
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gas
plasma
cvd method
containing gas
silicon
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Ryo Someya
亮 染矢
Tetsuo Ogata
哲郎 尾形
Eisaku Watanabe
栄作 渡邊
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Canon Anelva Corp
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    • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
    • C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
    • C23C16/448—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating characterised by the method used for generating reactive gas streams, e.g. by evaporation or sublimation of precursor materials
    • C23C16/452—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating characterised by the method used for generating reactive gas streams, e.g. by evaporation or sublimation of precursor materials by activating reactive gas streams before their introduction into the reaction chamber, e.g. by ionisation or addition of reactive species
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    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
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    • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
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    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
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    • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
    • C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
    • C23C16/4401—Means for minimising impurities, e.g. dust, moisture or residual gas, in the reaction chamber
    • C23C16/4405—Cleaning of reactor or parts inside the reactor by using reactive gases
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02107—Forming insulating materials on a substrate
    • H01L21/02109—Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates
    • H01L21/02112—Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates characterised by the material of the layer
    • H01L21/02123—Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates characterised by the material of the layer the material containing silicon
    • H01L21/02164—Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates characterised by the material of the layer the material containing silicon the material being a silicon oxide, e.g. SiO2
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02107—Forming insulating materials on a substrate
    • H01L21/02109—Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates
    • H01L21/02112—Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates characterised by the material of the layer
    • H01L21/02123—Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates characterised by the material of the layer the material containing silicon
    • H01L21/0217—Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates characterised by the material of the layer the material containing silicon the material being a silicon nitride not containing oxygen, e.g. SixNy or SixByNz
    • H—ELECTRICITY
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    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
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    • H01L21/02107—Forming insulating materials on a substrate
    • H01L21/02109—Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates
    • H01L21/02205—Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates the layer being characterised by the precursor material for deposition
    • H01L21/02208—Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates the layer being characterised by the precursor material for deposition the precursor containing a compound comprising Si
    • H01L21/02211—Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates the layer being characterised by the precursor material for deposition the precursor containing a compound comprising Si the compound being a silane, e.g. disilane, methylsilane or chlorosilane
    • H—ELECTRICITY
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    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02107—Forming insulating materials on a substrate
    • H01L21/02225—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer
    • H01L21/0226—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer formation by a deposition process
    • H01L21/02263—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer formation by a deposition process deposition from the gas or vapour phase
    • H01L21/02271—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer formation by a deposition process deposition from the gas or vapour phase deposition by decomposition or reaction of gaseous or vapour phase compounds, i.e. chemical vapour deposition
    • H01L21/02274—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer formation by a deposition process deposition from the gas or vapour phase deposition by decomposition or reaction of gaseous or vapour phase compounds, i.e. chemical vapour deposition in the presence of a plasma [PECVD]

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Abstract

PROBLEM TO BE SOLVED: To reduce a time period required for a seasoning process when a silicon compound is deposited in a remote plasma-induced CVD method to improve productivity.SOLUTION: In a seasoning process of a remote plasma-induced CVD method in which a vacuum vessel is separated into a plasma generation space and a substrate processing space with a partition wall, while in general a material gas is flowed in the plasma generation space and a silicon containing gas is flowed in the substrate processing space, by flowing in both material gas and silicon containing gas into the plasma generation space, a time period required for the seasoning process can be significantly reduced.

Description

本発明は、プラズマ誘起ＣＶＤ（Ｃｈｅｍｉｃａｌ Ｖａｐｏｒ Ｄｅｐｏｓｉｔｉｏｎ）方法に関し、特に、プラズマ生成空間と基板処理空間とに分離されたリモートプラズマ誘起ＣＶＤ方法に関する。   The present invention relates to a plasma-induced CVD (Chemical Vapor Deposition) method, and more particularly, to a remote plasma-induced CVD method separated into a plasma generation space and a substrate processing space.

一般にプラズマ誘起ＣＶＤ方法は，原料ガスをプラズマによって化学反応させて目的の基板の表面に薄膜を成膜する方法である．通常，このプラズマ誘起ＣＶＤ方法は処理基板の表面にプラズマが直接晒されている状態で成膜を実施している．
このため，プラズマ中の荷電粒子などの影響で成膜する薄膜やあらかじめ下地に形成されている素子にダメージが生じてしまう問題があった．このダメージを回避するために該プラズマを該基板の表面から隔離した、リモートプラズマ誘起ＣＶＤ方法が提案されている（特許文献１、特許文献２）。 In general, the plasma-induced CVD method is a method in which a raw material gas is chemically reacted with plasma to form a thin film on the surface of a target substrate. In general, this plasma-induced CVD method is performed with the plasma directly exposed to the surface of the processed substrate.
For this reason, there was a problem that the thin film to be deposited and the element previously formed on the substrate were damaged by the influence of charged particles in the plasma. In order to avoid this damage, a remote plasma induced CVD method in which the plasma is isolated from the surface of the substrate has been proposed (Patent Documents 1 and 2).

このリモートプラズマ誘起ＣＶＤ装置では、高エネルギーのプラズマ粒子の入射を抑制し、リモートプラズマを実現するために、チャンバー内をプラズマ生成空間と基板処理空間に画す隔壁を有している。隔壁はプラズマ生成空間と基板処理空間を繋ぐ複数の貫通孔を有す。また隔壁にはガスを基板処理空間に流入させるためのガス流入口が設けられている。   In this remote plasma induced CVD apparatus, in order to suppress the incidence of high energy plasma particles and realize remote plasma, the remote plasma induction CVD apparatus has a partition wall that divides the chamber into a plasma generation space and a substrate processing space. The partition wall has a plurality of through holes that connect the plasma generation space and the substrate processing space. The partition wall is provided with a gas inlet for allowing gas to flow into the substrate processing space.

一般にＣＶＤ処理では堆積される膜が基板上に堆積するだけでなく、例えばチャンバー内のシールド、基板ホルダ、チャンバーの内壁などにも堆積する。この基板以外への堆積膜の剥離が、ＣＶＤ処理中の条件に影響を与えることにより、所望の膜質が得られない問題がある。そのため、ＣＶＤチャンバーは定期的にクリーニングが行われる。ＣＶＤ処理によって処理基板上に珪素化合物を成膜した場合、クリーニングは一般に三フッ化窒素（ＮＦ３）のようなフッ素含有ガスをチャンバー内に流入させ、放電させることによってなされる。フッ素含有ガスはチャンバー内の堆積膜と反応し、ガス状のフッ素含有生成物を形成する。該生成物はチャンバー排気システムを通して排気される。またクリーニング工程後にチャンバー内のコンディションを整え、所望の膜質を得るためのシーズニング工程が行われることもある。 In general, in a CVD process, a film to be deposited is not only deposited on a substrate but also deposited on a shield in a chamber, a substrate holder, an inner wall of the chamber, and the like. The peeling of the deposited film other than the substrate affects the conditions during the CVD process, so that a desired film quality cannot be obtained. Therefore, the CVD chamber is periodically cleaned. When a silicon compound film is formed on a processing substrate by a CVD process, cleaning is generally performed by flowing a fluorine-containing gas such as nitrogen trifluoride (NF 3 ) into the chamber and discharging it. The fluorine-containing gas reacts with the deposited film in the chamber to form a gaseous fluorine-containing product. The product is exhausted through a chamber exhaust system. In addition, a seasoning process for adjusting the condition in the chamber after the cleaning process and obtaining a desired film quality may be performed.

ここで、上述したリモートプラズマ誘起ＣＶＤ方法に係る装置におけるシリコン化合物の成膜では、クリーニング工程及びシーズニング工程は以下のように行われていた。
即ち、クリーニング工程においては、プラズマ生成空間にＮＦ３を流入してＮＦ３のプラズマを形成し、該プラズマを隔壁を通して基板処理空間に流入させることでチャンバー内に付着した珪素化合物を除去していた。
シーズニング工程においては、プラズマ生成空間に原料ガスを流入させてプラズマを形成して活性種を生成し、該活性種を隔壁を通して基板処理空間に流入させ、一方で基板処理空間に珪素含有ガスを流入させることで、原料ガスの活性種と珪素含有ガスを反応させ、チャンバー内のコンディションを整えていた。なお、このシーズニング工程は、一般的にチャンバー内の雰囲気を成膜する際のコンディションに整えるために、成膜時と同条件のプロセスで行われる。 Here, in the silicon compound film formation in the apparatus related to the remote plasma induced CVD method described above, the cleaning process and the seasoning process are performed as follows.
That is, in the cleaning process, NF 3 was introduced into the plasma generation space to form NF 3 plasma, and the silicon compound adhering in the chamber was removed by flowing the plasma into the substrate processing space through the partition walls. .
In the seasoning process, a raw material gas is introduced into the plasma generation space to form plasma to generate active species, and the active species are introduced into the substrate processing space through the partition wall, while a silicon-containing gas is introduced into the substrate processing space. As a result, the active species of the source gas and the silicon-containing gas were reacted to adjust the condition in the chamber. This seasoning step is generally performed by a process under the same conditions as those for film formation in order to adjust the atmosphere in the chamber to a condition for film formation.

特開２０００−３４５３４９号公報JP 2000-345349 A 特開２００１−１３５６２８号公報JP 2001-135628 A

しかし、上述した従来のリモートプラズマ誘起ＣＶＤ法では、シーズニングに要する時間が長く、更なる生産性向上のため、シーズニングに要する時間の短縮が望まれるようになった。
本発明はこの課題に鑑み成されたものであり、基板処理空間とプラズマ生成空間を有するリモートプラズマ誘起ＣＶＤ方法における珪素化合物の成膜において、シーズニングに要する時間を短縮することを目的とする。 However, in the conventional remote plasma induced CVD method described above, the time required for seasoning is long, and it has become desirable to reduce the time required for seasoning in order to further improve productivity.
The present invention has been made in view of this problem, and an object thereof is to shorten the time required for seasoning in the formation of a silicon compound in a remote plasma induced CVD method having a substrate processing space and a plasma generation space.

上記課題を解決するため、本願発明は、成膜工程、クリーニング工程及びシーズニング工程を有するリモートプラズマ誘起ＣＶＤ方法であって、前記成膜工程は、前記プラズマ生成空間に原料ガスを流入させる工程と、前記プラズマ生成空間で前記原料ガスのプラズマを形成し、前記原料ガスの活性種を生成する工程と、前記基板処理空間に珪素含有ガスを流入させる工程と、前記原料ガスの活性種を隔壁を通じて前記基板処理空間に流入させる工程と、前記原料ガスの活性種と前記珪素含有ガスを反応させて珪素化合物を処理基板上に成膜する工程を有し、前記シーズニング工程は、前記プラズマ生成空間に前記珪素含有ガス及び前記原料ガスを流入させる工程と、前記プラズマ生成空間で前記珪素含有ガス及び前記原料ガスのプラズマを形成し反応させる工程を有することを特徴とする。   In order to solve the above problems, the present invention is a remote plasma induced CVD method having a film forming process, a cleaning process, and a seasoning process, wherein the film forming process includes a step of flowing a source gas into the plasma generation space; Forming a plasma of the source gas in the plasma generation space to generate active species of the source gas; flowing a silicon-containing gas into the substrate processing space; and A step of flowing into the substrate processing space; and a step of reacting an active species of the source gas with the silicon-containing gas to form a silicon compound on the processing substrate, wherein the seasoning step is performed in the plasma generation space. A step of flowing a silicon-containing gas and the source gas, and a plasma of the silicon-containing gas and the source gas in the plasma generation space. It characterized by having a step of no response.

本発明によればシーズニング工程に要する時間を短縮することができ、生産性を向上させることが可能となる。   According to the present invention, the time required for the seasoning process can be shortened, and productivity can be improved.

本発明に係るリモートプラズマ誘起ＣＶＤ方法を行うための装置を示す図である。It is a figure which shows the apparatus for performing the remote plasma induction CVD method which concerns on this invention. 図１に示す装置の貫通孔部分を拡大した図である。It is the figure which expanded the through-hole part of the apparatus shown in FIG. 図１に示す装置の隔壁を上から見た図である。It is the figure which looked at the partition of the apparatus shown in FIG. 1 from the top.

以下図面を参照しながら本発明の実施形態を説明する。   Embodiments of the present invention will be described below with reference to the drawings.

図１は本発明に係るリモートプラズマ誘起ＣＶＤ装置１００の模式図である。図１において、１は真空容器、２は電極、２ａは電極に穿孔された孔、３は電力導入棒、４は電力導入棒３の外周部を覆う絶縁物、５は第一のガスを導入する第一のガス導入手段、６はクリーニングガス導入手段、７及び８は絶縁物、９は後述する隔壁を地絡するための金属等から出来ている電気的導体、１０は電極２の上、孔２ａの中及び電極２の下に拡がるプラズマ生成空間を示す。   FIG. 1 is a schematic view of a remote plasma induced CVD apparatus 100 according to the present invention. In FIG. 1, 1 is a vacuum vessel, 2 is an electrode, 2a is a hole drilled in the electrode, 3 is a power introduction rod, 4 is an insulator covering the outer periphery of the power introduction rod 3, and 5 is a first gas introduction First gas introducing means, 6 is a cleaning gas introducing means, 7 and 8 are insulators, 9 is an electrical conductor made of metal for grounding a partition wall to be described later, 10 is on the electrode 2, A plasma generation space extending in the hole 2a and under the electrode 2 is shown.

２０は隔壁を示している。２１は貫通孔、２２は拡散孔、２３は内部空間、２４は原料ガスを導入する第二のガス導入手段、２５は孔形成領域を表している。ここで、貫通孔２１はプラズマが発生している部分よりなるプラズマ生成空間１０（第一の空間）と隔壁２０の下に位置する基板処理空間１１（第二の空間）を繋ぐ複数の孔であり、隔壁２０を柱状の形をして貫いている。   Reference numeral 20 denotes a partition wall. Reference numeral 21 denotes a through hole, 22 denotes a diffusion hole, 23 denotes an internal space, 24 denotes a second gas introduction means for introducing a source gas, and 25 denotes a hole forming region. Here, the through-hole 21 is a plurality of holes that connect the plasma generation space 10 (first space) formed of a portion where plasma is generated and the substrate processing space 11 (second space) located below the partition wall 20. Yes, penetrating the partition wall 20 in a columnar shape.

内部空間２３は柱状部以外で繋がっており、内部空間２３の全面に亘ってほぼ一定の圧力になっている。従って、拡散孔２２を通して噴出されるガスの流量も、拡散孔２２の位置によらずほぼ一定となっている。   The internal space 23 is connected except for the columnar part, and the pressure is almost constant over the entire surface of the internal space 23. Therefore, the flow rate of the gas ejected through the diffusion hole 22 is also substantially constant regardless of the position of the diffusion hole 22.

３０は基板ホルダ、３１はその内部に埋設されているヒータである。そして、基板ホルダ３０の上部には基板１４が載置されている。１１は基板処理空間、１２は排気ポート、１３はターボ分子ポンプ等の排気手段である。   Reference numeral 30 denotes a substrate holder, and 31 denotes a heater embedded therein. A substrate 14 is placed on the substrate holder 30. Reference numeral 11 denotes a substrate processing space, 12 denotes an exhaust port, and 13 denotes exhaust means such as a turbo molecular pump.

図２は、隔壁２０の一部の拡大図である。同一の構成要素には同一の符号を付して、説
明は省略する。 FIG. 2 is an enlarged view of a part of the partition wall 20. The same components are denoted by the same reference numerals, and description thereof is omitted.

プラズマ１０ａはプラズマ生成空間１０で発生するプラズマである。矢印４１は該プラズマの活性種が貫通孔２１を通り基板処理空間１１に供給される方向を示し、矢印４２は第二のガス導入手段２４より内部空間２３に導入された原料ガスが拡散孔２２を通り基板処理空間１１に供給される方向を示している。   The plasma 10 a is plasma generated in the plasma generation space 10. An arrow 41 indicates the direction in which the active species of the plasma is supplied to the substrate processing space 11 through the through-hole 21, and an arrow 42 indicates that the source gas introduced into the internal space 23 from the second gas introduction means 24 is diffused 22. The direction of supply to the substrate processing space 11 is shown.

貫通孔２１は、３つの部分に分けることが出来る。プラズマ生成空間１０の側の２１ａはより小さな直径を有している。一方、基板処理空間１１の側の２１ｃは大きな直径となっている。その間は錐状の形状をした２１ｂで繋がっている。なお本実施形態においては、２１ａの直径が２１ｃの直径よりも小さい構造としたが、これが逆であっても問題は無い。詳細な条件については特開２０００−３４５３４９に開示されている。   The through hole 21 can be divided into three parts. 21a on the side of the plasma generation space 10 has a smaller diameter. On the other hand, 21c on the substrate processing space 11 side has a large diameter. In the meantime, it is connected by a cone-shaped 21b. In the present embodiment, the diameter of 21a is smaller than the diameter of 21c, but there is no problem even if this is reversed. Detailed conditions are disclosed in JP-A-2000-345349.

このような形状をしているので、孔部に放電が入り込み、その結果プラズマが基板処理空間１１に漏れるのを防止できる。また、孔部では放電が生じ易いが、図２の構造ではプラズマ１０に対しては、隔壁は以下で記述する形状に比べてよりフラットである為、異常放電も起こり難い。また、径の小さな部分２１ａの長さが短いので製作も容易であるというメリットがある。   Since it has such a shape, it is possible to prevent discharge from entering the hole, and as a result, leakage of plasma into the substrate processing space 11. Further, although discharge is likely to occur in the hole portion, in the structure shown in FIG. 2, since the partition wall is flatter than the shape described below, abnormal discharge hardly occurs with respect to the plasma 10. Moreover, since the length of the small diameter part 21a is short, there exists an advantage that manufacture is also easy.

図３は、本発明に係わる隔壁２０に形成される貫通孔２１及び拡散孔２２の穿孔の仕方
を説明するための図である。ここで、今まで説明した実質同一の構成要素には同一の符号
を付して、説明を省略する。 FIG. 3 is a view for explaining how to drill the through holes 21 and the diffusion holes 22 formed in the partition wall 20 according to the present invention. Here, substantially the same components as described above are denoted by the same reference numerals, and description thereof is omitted.

貫通孔２１及び拡散孔２２は、孔形成領域２５の内側に形成される。例えば、円板状の
基板を処理する場合には孔形成領域２５は円状に形成すると良い。そして、例えば貫通孔
２１及び拡散孔２２はその孔形成領域と同心の異なる径を持つ円周上に形成することで実
現できる。 The through hole 21 and the diffusion hole 22 are formed inside the hole forming region 25. For example, when processing a disk-shaped substrate, the hole forming region 25 is preferably formed in a circular shape. For example, the through hole 21 and the diffusion hole 22 can be realized by forming them on a circumference having different diameters concentric with the hole forming region.

拡散孔２２は孔形成領域２５内全域に亘って単位面積あたり同一の開口率で配置されている。このような配置は、同一の孔径を持つ拡散孔２２を、同一のピッチで円周上に配置し、且つ隣接する円の径方向のピッチを同一にして配置することにより実現できる。   The diffusion holes 22 are arranged with the same aperture ratio per unit area over the whole area of the hole forming region 25. Such an arrangement can be realized by arranging the diffusion holes 22 having the same hole diameter on the circumference at the same pitch and arranging the adjacent circles at the same radial pitch.

一方、貫通孔２１については周辺部における配置を増やし、中心部に比べ周辺部での単位面積あたりの開口率を大きくしている。   On the other hand, about the through-hole 21, the arrangement | positioning in a peripheral part is increased and the aperture ratio per unit area in a peripheral part is enlarged compared with the center part.

上述した装置を用いて、処理基板上に珪素化合物の成膜を行う。まず、第一のガス導入手段５によりプラズマ生成空間１０に原料ガスを流入させてプラズマを形成し、第二のガス導入手段２４により基板処理空間１１に珪素含有ガスを流入させて窒素含有ガスの活性種と反応させることで行う。   Using the above-described apparatus, a silicon compound is formed on the processing substrate. First, a source gas is introduced into the plasma generation space 10 by the first gas introduction means 5 to form a plasma, and a silicon-containing gas is introduced into the substrate processing space 11 by the second gas introduction means 24 so that the nitrogen-containing gas is formed. This is done by reacting with active species.

次のクリーニング工程は、珪素化合物の成膜後にフッ化ガスを用いた従来のクリーニング方法と同様に行うことができる。例として、プラズマ生成空間１０にＮＦ３ガスを流入させてプラズマを形成し、基板処理空間１１に窒素（Ｎ２）ガスを流入させることでチャンバー内に堆積した膜の除去を行う。 The next cleaning step can be performed in the same manner as a conventional cleaning method using a fluorinated gas after the silicon compound film is formed. As an example, NF 3 gas is introduced into the plasma generation space 10 to form plasma, and nitrogen (N 2 ) gas is introduced into the substrate processing space 11 to remove the film deposited in the chamber.

次にシーズニング工程を行う。ここで本発明者はシーズニング工程において、通常成膜工程と同条件で行われるところを、成膜工程に用いた原料ガス及び珪素含有ガスをプラズマ生成空間１０に流入させ、プラズマを形成することでシーズニングに要する時間を大幅に短縮できることを見出した。   Next, a seasoning process is performed. Here, the inventor performs the seasoning process under the same conditions as the normal film forming process by flowing the source gas and silicon-containing gas used in the film forming process into the plasma generation space 10 to form plasma. It has been found that the time required for seasoning can be greatly reduced.

（実施例）
以下に本実施形態に係る具体的な実施例を示す。 (Example)
Specific examples according to this embodiment will be described below.

真空状態においてリモートプラズマ誘起ＣＶＤ方法によりＳｉＮを処理基板上に成膜した。ＳｉＮの成膜条件としてプラズマ生成空間１０にアンモニア（ＮＨ３）ガスを流入させ、ＮＨ３ガスのプラズマを形成した。ＮＨ３ガスのプラズマ形成から１０秒後に基板処理空間１１にモノシラン（ＳｉＨ４）ガスとＡｒガスの混合ガスを流入させ、貫通孔２１を通ったＮＨ３の活性種と反応させた。各ガスの流量はＮＨ３ガスが１５００ｓｃｃｍ、ＳｉＨ４ガスが４０ｓｃｃｍ、Ａｒガスが２５０ｓｃｃｍとした。この反応によりＳｉＮを３０ｎｍ成膜した。 In a vacuum state, SiN was formed on the processing substrate by a remote plasma induced CVD method. As a SiN film forming condition, ammonia (NH 3 ) gas was introduced into the plasma generation space 10 to form NH 3 gas plasma. Ten seconds after the NH 3 gas plasma was formed, a mixed gas of monosilane (SiH 4 ) gas and Ar gas was introduced into the substrate processing space 11 to react with the active species of NH 3 that passed through the through holes 21. The flow rates of the respective gases were 1500 sccm for NH 3 gas, 40 sccm for SiH 4 gas, and 250 sccm for Ar gas. A 30 nm SiN film was formed by this reaction.

成膜工程を行った後にクリーニング工程を行った。クリーニング工程の条件としては、プラズマ生成空間１０にＮＦ３ガスを６００ｓｃｃｍで流入させ、基板処理空間１１にＡｒガスを１５０ｓｃｃｍで流入させる。ＮＦ３ガスのプラズマを形成することで、チャンバー内に残留したＮＨ３ガスの活性種やチャンバー内に堆積したＳｉＮ膜の除去を行う。本実施例におけるクリーニング工程の所要時間は２０秒であった。 A cleaning process was performed after the film forming process. As conditions for the cleaning process, NF 3 gas is flowed into the plasma generation space 10 at 600 sccm, and Ar gas is flowed into the substrate processing space 11 at 150 sccm. By forming plasma of NF 3 gas, the active species of NH 3 gas remaining in the chamber and the SiN film deposited in the chamber are removed. The time required for the cleaning process in this example was 20 seconds.

クリーニング工程の後にシーズニング工程を行った。シーズニング工程の条件としては、プラズマ生成空間１０にＮＨ３ガスを１５００ｓｃｃｍ及びＳｉＨ４ガスを２００ｓｃｃｍで流入させる。その後ＮＨ３ガス及びＳｉＨ４ガスのプラズマを形成し、反応させることでチャンバー内にＳｉＮを形成しシーズニングを行う。本実施例におけるシーズニング工程の所要時間は１０秒であった。 A seasoning process was performed after the cleaning process. As a condition for the seasoning process, NH 3 gas is flowed into the plasma generation space 10 at 1500 sccm and SiH 4 gas is flowed at 200 sccm. Thereafter, plasma of NH 3 gas and SiH 4 gas is formed and reacted to form SiN in the chamber for seasoning. The time required for the seasoning process in this example was 10 seconds.

ここで、本発明に係るシーズニング工程を行う場合、ＳｉＮの成膜量に対してクリーニング工程を行う頻度を高くすることが好ましい。何故ならば、後述する本発明に係るシーズニング工程においては、ＮＨ３ガスとＳｉＨ４ガスを共にプラズマ生成空間１０に流入させてプラズマを形成するため、プラズマ生成空間１０に反応生成物であるＳｉＮの堆積量が増加する。従って、クリーニング工程が１回の成膜毎に行われることが最も好ましい。 Here, when performing the seasoning process according to the present invention, it is preferable to increase the frequency of performing the cleaning process with respect to the SiN film formation amount. This is because, in the seasoning process according to the present invention, which will be described later, NH 3 gas and SiH 4 gas are caused to flow into the plasma generation space 10 to form plasma, so that the reaction product SiN is formed in the plasma generation space 10. The amount of deposition increases. Therefore, it is most preferable that the cleaning process is performed for each film formation.

ここで比較例として従来行っていたシーズニング工程による所要時間を示す。また、成膜工程及びクリーニング工程については上述した実施例と同条件で行った。   Here, as a comparative example, the time required for the seasoning process conventionally performed is shown. The film forming process and the cleaning process were performed under the same conditions as in the above-described examples.

次にシーズニング工程を行った。シーズニング工程の条件としては、プラズマ生成空間１０にＮＨ３ガスを２２５０ｓｃｃｍ流入させ、基板処理空間１１にＡｒを２５０ｓｃｃｍ流入させる。その後ＮＨ３ガスのプラズマを形成し、貫通孔２１を通してＮＨ３ガスの活性種を基板処理空間１１に流す。ＮＨ３ガスのプラズマを形成後、ＳｉＨ４ガスを基板処理空間１１に２２５０ｓｃｃｍで流入させ、ＮＨ３ガスの活性種と反応させる。本比較例におけるシーズニング工程に要した時間は１．５時間であった。 Next, a seasoning process was performed. As the conditions for the seasoning process, NH 3 gas is introduced into the plasma generation space 10 at 2250 sccm, and Ar is introduced into the substrate processing space 11 at 250 sccm. Thereafter, plasma of NH 3 gas is formed, and activated species of NH 3 gas is flowed into the substrate processing space 11 through the through hole 21. After the NH 3 gas plasma is formed, SiH 4 gas is flowed into the substrate processing space 11 at 2250 sccm, and reacted with the activated species of NH 3 gas. The time required for the seasoning process in this comparative example was 1.5 hours.

従って、本発明に係るシーズニング工程を用いることで、従来１．５時間要していたシーズニング工程が１０秒で完了する。   Therefore, by using the seasoning process according to the present invention, the seasoning process, which conventionally took 1.5 hours, is completed in 10 seconds.

なお、本実施例で示したガス流量は本発明を実施する上での一例に過ぎず、ガス流量は本発明の本質的な部分ではない。即ち、プラズマ生成空間１０に窒素含有ガスと珪素含有ガスを流入させてプラズマを形成し、反応させることが肝要である。他の窒素含有ガスの例としては亜酸化窒素（Ｎ２Ｏ）ガスやＮ２ガス、またはこれらの混合を用いることができ、珪素含有ガスとしてはジシラン（Ｓｉ２Ｈ６）ガスを用いることができる。 In addition, the gas flow rate shown in the present embodiment is merely an example for carrying out the present invention, and the gas flow rate is not an essential part of the present invention. In other words, it is important to cause a nitrogen-containing gas and a silicon-containing gas to flow into the plasma generation space 10 to form and react with the plasma. Examples of other nitrogen-containing gas may include nitrous oxide (N 2 O) gas, N 2 gas, or a mixture thereof, and disilane (Si 2 H 6 ) gas may be used as the silicon-containing gas. it can.

なおシーズニング工程に要した時間とは、その後の成膜工程において所望の膜質が得られる状態となるまでに要した時間であって、実施例及び比較例における所望の膜質の条件は同じとした。   The time required for the seasoning process is the time required until a desired film quality is obtained in the subsequent film forming process, and the conditions for the desired film quality in the examples and comparative examples are the same.

以上の実施例ではＳｉＮ膜の成膜について説明したが、ＳｉＮ膜以外に酸化シリコン（ＳｉＯ２）膜をリモートプラズマ誘起ＣＶＤ法で成膜する際にも本発明は適用可能である。その場合、窒素含有ガスの代わりに酸素含有ガスを用いる。例えば、珪素含有ガスとしてＳｉＨ４ガスまたはＳｉ２Ｈ６ガス、酸素含有ガスとしては酸素ガス（Ｏ２）を好適に用いることができる。 In the above embodiments, the formation of the SiN film has been described. However, the present invention can also be applied when a silicon oxide (SiO 2 ) film is formed by a remote plasma induced CVD method in addition to the SiN film. In that case, oxygen-containing gas is used instead of nitrogen-containing gas. For example, SiH 4 gas or Si 2 H 6 gas can be suitably used as the silicon-containing gas, and oxygen gas (O 2 ) can be suitably used as the oxygen-containing gas.

さらに別の実施形態としてＳｉＮ膜の代わりにＳｉＮとＳｉＯ２が混在した膜をリモートプラズマ誘起ＣＶＤ方法で成膜する際にも本発明は適用可能である。その場合、窒素含有ガスだけでなく酸素含有ガスも混合させる。例えば、珪素含有ガスとしてＳＩＨ４ガスまたはＳｉ２Ｈ６ガス、窒素含有ガスとしてＮＨ３ガス、酸素含有ガスとしてＯ２ガスを好適に用いることができる。 As another embodiment, the present invention can also be applied when a film containing SiN and SiO 2 is formed by a remote plasma induced CVD method instead of the SiN film. In that case, not only nitrogen-containing gas but also oxygen-containing gas is mixed. For example, SIH 4 gas or Si 2 H 6 gas can be suitably used as the silicon-containing gas, NH 3 gas as the nitrogen-containing gas, and O 2 gas as the oxygen-containing gas.

１００ リモートプラズマ誘起ＣＶＤ装置
１ 真空容器
２ 電極
２ａ 電極に穿孔された孔
３ 電力導入棒
４ 、７、８ 絶縁物
５ 原料ガス導入手段
６ クリーニングガス導入手段
９ 電気的導体
１０ プラズマ生成空間
１０ａ プラズマ
１１ 基板処理空間
１２ 排気ポート
１３ 排気手段
１４ 基板
２０ 隔壁
２１ 貫通孔
２２ 拡散孔
２３ 内部空間
２４ 珪素含有ガス導入手段
３０ 基板ホルダ
３１ ヒータ
４１ 活性種の流れの方向
４２ 原料ガスの流れの方向
DESCRIPTION OF SYMBOLS 100 Remote plasma induction CVD apparatus 1 Vacuum vessel 2 Electrode 2a Hole 3 drilled in electrode 3 Power introduction rods 4, 7, 8 Insulator 5 Source gas introduction means 6 Cleaning gas introduction means 9 Electrical conductor 10 Plasma generation space 10a Plasma 11 Substrate processing space 12 Exhaust port 13 Exhaust means 14 Substrate 20 Partition wall 21 Through hole 22 Diffusion hole 23 Internal space 24 Silicon-containing gas introduction means 30 Substrate holder 31 Heater 41 Flow direction of active species 42 Flow direction of source gas

Claims (7)

真空容器内で被処理基板上に珪素化合物を堆積させるＣＶＤ方法であって、
前記ＣＶＤ方法は、前記真空容器の内部を複数の孔が形成された隔壁によってプラズマ生成空間と基板処理空間に分けて行われ、
前記ＣＶＤ方法は成膜工程、クリーニング工程及びシーズニング工程を有し、
前記成膜工程は、
前記プラズマ生成空間に原料ガスを流入させる工程と、
前記プラズマ生成空間で前記原料ガスのプラズマを形成し、前記原料ガスの活性種を生成する工程と、
前記基板処理空間に珪素含有ガスを流入させる工程と、
前記原料ガスの活性種を隔壁を通じて前記基板処理空間に流入させる工程と、
前記原料ガスの活性種と前記珪素含有ガスを反応させて珪素化合物を前記被処理基板上に成膜する工程を有し、
前記シーズニング工程は、
前記プラズマ生成空間に前記珪素含有ガス及び前記原料ガスを流入させる工程と、
前記プラズマ生成空間で前記珪素含有ガス及び前記原料ガスのプラズマを形成し反応させる工程を有することを特徴とするＣＶＤ方法。 A CVD method for depositing a silicon compound on a substrate to be processed in a vacuum container,
The CVD method is performed by dividing the inside of the vacuum vessel into a plasma generation space and a substrate processing space by a partition wall in which a plurality of holes are formed.
The CVD method includes a film forming process, a cleaning process, and a seasoning process,
The film forming step includes
Flowing a source gas into the plasma generation space;
Forming a plasma of the source gas in the plasma generation space to generate active species of the source gas;
Flowing a silicon-containing gas into the substrate processing space;
Allowing the active species of the source gas to flow into the substrate processing space through a partition;
Reacting the active species of the source gas with the silicon-containing gas to form a silicon compound on the substrate to be processed;
The seasoning step includes
Flowing the silicon-containing gas and the source gas into the plasma generation space;
A CVD method comprising a step of forming and reacting plasma of the silicon-containing gas and the source gas in the plasma generation space. 前記原料ガスは窒素含有ガスであることを特徴とする請求項１に記載のＣＶＤ方法。   The CVD method according to claim 1, wherein the source gas is a nitrogen-containing gas. 前記窒素含有ガスはアンモニアガス、窒素ガスまたは亜酸化窒素、もしくはこれらの混合ガスであり、前記珪素含有ガスはモノシランガスまたはジシランガスであることを特徴とする請求項２に記載のＣＶＤ方法。   The CVD method according to claim 2, wherein the nitrogen-containing gas is ammonia gas, nitrogen gas, nitrous oxide, or a mixed gas thereof, and the silicon-containing gas is monosilane gas or disilane gas. 前記原料ガスは酸素含有ガスであることを特徴とする請求項１に記載のＣＶＤ方法。   The CVD method according to claim 1, wherein the source gas is an oxygen-containing gas. 前記酸素含有ガスは酸素ガスであり、前記珪素含有ガスはモノシランガスまたはジシランガスであることを特徴とする請求項４に記載のＣＶＤ方法。   The CVD method according to claim 4, wherein the oxygen-containing gas is an oxygen gas, and the silicon-containing gas is a monosilane gas or a disilane gas. 前記原料ガスは窒素含有ガスと酸素含有ガスの混合ガスであることを特徴とする請求項１に記載のＣＶＤ方法。   The CVD method according to claim 1, wherein the source gas is a mixed gas of a nitrogen-containing gas and an oxygen-containing gas. 前記窒素含有ガスはアンモニアガス、窒素ガスまたは亜酸化窒素、もしくはこれらの混合ガスであり、
前記酸素含有ガスは酸素ガスであり、
前記珪素含有ガスはモノシランガスまたはジシランガスであることを特徴とする請求項６に記載のＣＶＤ方法。 The nitrogen-containing gas is ammonia gas, nitrogen gas or nitrous oxide, or a mixed gas thereof,
The oxygen-containing gas is oxygen gas;
The CVD method according to claim 6, wherein the silicon-containing gas is monosilane gas or disilane gas.
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