JPH01173726A - Plasma device and plasma treating method - Google Patents

Abstract

PURPOSE:To make it possible to form a highly densed film and to conduct a uniform doping and the like by a method wherein an electrode, with which the ions in a plasma stream will be scanned, is provided between a plasma generating chamber and a sample chamber, a thin film is deposited while the ions are being scanned, and then a doping and the like is conducted. CONSTITUTION:The microwaves of a microwave power source 1 are supplied to a plasma chamber 2, and electronic cyclotron resonance is generated by an external electromagnet 3. Paralleled flat plate scanning electrodes 4 and 5, with which ions in a plasma stream 8 coming from the plasma chamber 2, will be scanned, are provided between the plasma chamber 2 and a sample chamber 7. Triangular-wave voltage, for example, is applied to the electrodes 4 and 5, a thin film is formed or a doping is conducted on the sample 6 provided on a sample stand 9 while the ions in the plasma stream 8 led out from a divergent magnetic field are being scanned. Through these procedures, a highly densed film can be formed on the whole surface, and a uniform doping can also be conducted.

Description

【発明の詳細な説明】 産業上の利用分野 本発明は、凹凸を有する表面に緻密なｉＮ　ｔＦＪを均
一に形成したり、或はダイナミックＲＡＭのトレンチ部
に均一に任意の不純物をドーピングすることでかきる等
高密度半導体集積回路や薄膜デバイスに利用できるきわ
めて波及効果の大きい重要な技術である。DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention can be applied by uniformly forming a dense iN tFJ on an uneven surface or by uniformly doping arbitrary impurities into a trench portion of a dynamic RAM. This is an important technology that can be used for high-density semiconductor integrated circuits and thin film devices, and has an extremely large ripple effect.

従来の技術 半導体デバイスが微細化するとともに、低温化形成及び
低イオンエネルギーの薄膜プロセスが要望され、これに
対する一つの手段として、近年マイクロ波電子サイクロ
トロン共鳴吸収ｊＦ：１ｅｃｔｒｏｎＣｙｃｌｏｔｒｏ
ｎ　　Ｒｅ５ｏｎａｎｃｅ）を応用したプラズマＣＶＤ
やエツチングが提案された。ＥＣＲプラズマを薄膜形成
に用いると室温付近の基板温度で緻密な膜形成ができる
。BACKGROUND TECHNOLOGY As semiconductor devices become smaller, there is a demand for thin film processes with low temperature formation and low ion energy.
Plasma CVD applying nRe5onance)
and etching were proposed. When ECR plasma is used to form a thin film, a dense film can be formed at a substrate temperature near room temperature.

発明が解決しようとする問題点 しかし、この方法をＶＬＳ　Ｉ等の層間絶縁膜形成等に
用いる場合、段差部での膜質が平坦部でのそれと異って
、エツチング速度がきわめて大きいとかカバレッジがよ
くないという問題がある。これは、ＩＩＱの緻密化にイ
オンが重要な役割を果たしているにも拘らず、側壁部に
は十分なイオン照射がなされないことが原因である。Problems to be Solved by the Invention However, when this method is used to form an interlayer insulating film such as VLSI, the quality of the film at the step part is different from that at the flat part, and the etching rate is extremely high and the coverage is poor. The problem is that there is no. This is because, although ions play an important role in densification of IIQ, sufficient ion irradiation is not performed on the sidewall portions.

問題点を解決するための手段 本発明は、上記問題点を解決するため、プラズマ室から
のプラズマ流中のイオンを走査して基板上に存在する側
壁部にもイオンが十分供給されるようにするため、プラ
ズマ発生室と試料室間に走査電極を設け、イオンを走査
して、基板に対するイオンの侵入角を変化させ側壁部に
もイオンを有効に供給しようとするものである。Means for Solving the Problems In order to solve the above-mentioned problems, the present invention scans the ions in the plasma flow from the plasma chamber so that the ions are sufficiently supplied to the side walls existing on the substrate. In order to do this, a scanning electrode is provided between the plasma generation chamber and the sample chamber, and the ions are scanned to change the angle of entry of the ions into the substrate, thereby effectively supplying the ions to the side walls.

作　　　用 本発明により、室温付近で水素量が少なく、低イオンエ
ネルギーで段差部に対しても緻密な絶縁膜の形成か可能
になる。Effects According to the present invention, it is possible to form a dense insulating film even on stepped portions with a small amount of hydrogen near room temperature and low ion energy.

実　　施　　例 図は、本発明によるプラズマ装置の構成概略図である。Example The figure is a schematic diagram of the configuration of a plasma device according to the present invention.

１は２．４５ＧＨｚのマグネトロン電源、２はプラズマ
室、３は電子サイクロトロン共鳴を生じさせる外部電磁
石、４は平行平板走査電極、５は電極４の平行平板走査
電極と垂直な平行平板走査電極で、それぞれに例えば三
角波電圧を印加して、発散磁場により引き出されたプラ
ズマ流８中のイオンを走査しつつ基板ホルダーに設置し
た試料６に薄膜形成あるいは不純物ドーピングを行なう
ことができる。９は試料台、１０は電源、１１゜１２は
ガス入口、１３は排気部である。1 is a 2.45 GHz magnetron power supply, 2 is a plasma chamber, 3 is an external electromagnet that generates electron cyclotron resonance, 4 is a parallel plate scanning electrode, 5 is a parallel plate scanning electrode perpendicular to the parallel plate scanning electrode of electrode 4, For example, by applying a triangular wave voltage to each of them, a thin film can be formed or impurity doping can be performed on the sample 6 placed on the substrate holder while scanning the ions in the plasma flow 8 drawn out by the divergent magnetic field. 9 is a sample stage, 10 is a power supply, 11° and 12 are gas inlets, and 13 is an exhaust section.

本装置を用いて、試料６として半導体基板例えば、シリ
コン基板上の凹凸を有する薄膜上にシリコン窒化膜のよ
うなパッシベーション膜を形成する場合の例を説明する
。この場合には、第１図に示すように、試料６の直径ｅ
より大きいプラズマ流の直径りの付近に走査電極４を設
け、更に他の走査電極５を試料台の前に設は走査するこ
とにより、基板上薄膜の側壁部にも十分なイオン照射が
行なわれ、全面的に緻密な膜の形成が行なわれる。例え
ば、シリコン窒化膜では、上部ガス入口よりＮ２ガスを
、下部ガス入口よりＳｉＨ４ガスを導入して、マイクロ
波電力３００　Ｗ、ガス圧５Ｘ１０　　Ｔｏｒｒ（Ｓｉ
Ｈ４＝６ＳＣＣＭ、Ｎ、−１５ＳＣＣＭ）の条件下で堆
積することにより、５００Ａ／ｌ１ｉｎの堆積速度が得
られる。また不純物ドーピングのためには、例えばＢ２
Ｈ６やＡｓＨ。An example of forming a passivation film such as a silicon nitride film on a thin film having irregularities on a semiconductor substrate, such as a silicon substrate, as the sample 6 will be described using this apparatus. In this case, as shown in FIG.
By installing a scanning electrode 4 near the diameter of the larger plasma flow, and placing another scanning electrode 5 in front of the sample stage for scanning, sufficient ion irradiation can be performed on the side walls of the thin film on the substrate. , a dense film is formed over the entire surface. For example, for a silicon nitride film, N2 gas is introduced from the upper gas inlet and SiH4 gas is introduced from the lower gas inlet, and the microwave power is 300 W and the gas pressure is 5 x 10 Torr (Si
A deposition rate of 500 A/1in is obtained by depositing under conditions of H4 = 6 SCCM, N, -15 SCCM). For impurity doping, for example, B2
H6 and AsH.

ガスを用い、基板に高周波バイアスを印加することによ
り半導体メモリーのｄ−ＲＡＭのトレンチキャパシタ等
の底部および側壁ドーピングとしても使うことが可能で
ある。以上はプラズマ流が広がった状態から、イオンを
走査する例を示したがＥＣＲプラズマ室に電圧印加した
り、基板ホルダー９に直流あるいは交流電圧を印加した
りしてイオンを加速する場合などで、プラズマ室のすぐ
後に走査電極を設置して、プラズマ処理してもよいこと
はいうまでもない。By using a gas and applying a high-frequency bias to the substrate, it can also be used for doping the bottom and side walls of trench capacitors in d-RAM semiconductor memories. The above example shows an example in which ions are scanned from a state where the plasma flow is spread out, but in cases where ions are accelerated by applying a voltage to the ECR plasma chamber, or by applying a DC or AC voltage to the substrate holder 9, etc. It goes without saying that plasma processing may be performed by installing a scanning electrode immediately after the plasma chamber.

発明の効果 本発明は、ＥＣＲプラズマＣＶＤ法の段差部でカバレッ
ジが悪いという欠点をな（し、更にトレンチドーピング
等において、ウェーハ内のドーピング均一性を向上させ
ることができる等工業上極めて大きな価値を有するもの
である。Effects of the Invention The present invention overcomes the drawback of poor coverage at stepped portions of the ECR plasma CVD method (and has extremely great industrial value, such as being able to improve doping uniformity within a wafer in trench doping, etc.). It is something that you have.

【図面の簡単な説明】[Brief explanation of the drawing]

図は本発明に用いるプラズマ処理装置の概略断面図であ
る− １・・・・・・マイクロ波電源、２・・・・・・プラズ
マ室、３・・・・・・電磁石、４，５・・・・・・走査
電極、６・・・・・・試料、７・・・・・・試料室、８
・・・・・・プラズマ流、９・・・・・・試料台、１０
・・・・・・電源（直流あるいは交流）。The figure is a schematic cross-sectional view of a plasma processing apparatus used in the present invention. ... Scanning electrode, 6 ... Sample, 7 ... Sample chamber, 8
...Plasma flow, 9...Sample stage, 10
...Power source (DC or AC).

Claims (2)

【特許請求の範囲】[Claims] （１）電子サイクロトロン共鳴を用いたプラズマ発生室
と試料室を有するプラズマ装置において、前記プラズマ
発生室と試料室間に前記プラズマ発生室からのプラズマ
流中のイオンを走査する電極を設置した構成を有するこ
とを特徴とするプラズマ装置。(1) In a plasma apparatus having a plasma generation chamber and a sample chamber using electron cyclotron resonance, an electrode for scanning ions in a plasma flow from the plasma generation chamber is installed between the plasma generation chamber and the sample chamber. A plasma device comprising: （２）電子サイクロトロン共鳴を用いたプラズマ発生室
と試料室を有するプラズマ装置を用いて、前記プラズマ
発生室と試料室間に前記プラズマ発生室からのプラズマ
中のイオンを走査しつつ、薄膜の堆積、ドーピング等を
行なうことを特徴とするプラズマ処理方法。(2) Deposition of a thin film while scanning ions in the plasma from the plasma generation chamber between the plasma generation chamber and the sample chamber using a plasma device that uses electron cyclotron resonance and has a plasma generation chamber and a sample chamber. A plasma processing method characterized by performing , doping, etc.