JPS6173333A - Cleaning device - Google Patents

Cleaning device

Info

Publication number
JPS6173333A
JPS6173333A JP19466684A JP19466684A JPS6173333A JP S6173333 A JPS6173333 A JP S6173333A JP 19466684 A JP19466684 A JP 19466684A JP 19466684 A JP19466684 A JP 19466684A JP S6173333 A JPS6173333 A JP S6173333A
Authority
JP
Japan
Prior art keywords
liquid
article
cathode
cleaned
hydrogen gas
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.)
Granted
Application number
JP19466684A
Other languages
Japanese (ja)
Other versions
JPH0566725B2 (en
Inventor
Kensuke Nakada
健介 中田
Koichiro Mizukami
水上　浩一郎
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hitachi Ltd
Original Assignee
Hitachi Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Hitachi Ltd filed Critical Hitachi Ltd
Priority to JP19466684A priority Critical patent/JPS6173333A/en
Publication of JPS6173333A publication Critical patent/JPS6173333A/en
Publication of JPH0566725B2 publication Critical patent/JPH0566725B2/ja
Granted legal-status Critical Current

Links

Classifications

    • 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
    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer
    • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic System or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
    • H01L21/302—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
    • H01L21/304—Mechanical treatment, e.g. grinding, polishing, cutting
    • H01L21/3046—Mechanical treatment, e.g. grinding, polishing, cutting using blasting, e.g. sand-blasting

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Manufacturing & Machinery (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Cleaning By Liquid Or Steam (AREA)
  • Cleaning Or Drying Semiconductors (AREA)

Abstract

PURPOSE:To finely clean an article to be cleaned by utilizing the cleaning action of hydrogen gas foaming by an electrolysis by holding liquid for performing cathode hydrogen gas foaming action by the electrolysis in a water tank, and providing power supplying means for forming a cathode at the article dipped in the liquid. CONSTITUTION:Liquid 5 for performing cathode hydrogen gas foaming action by an electrolysis is held in a water tank 4 by using the tank 4 for containing an article (wafer) 1 to be cleaned formed with a deep groove 2 and an insulating layer 3 in a cleaning device. An ANODE electrode 6 and a cathode electrode 7 made of Pt or Au are arranged in the liquid 5, the article 1 is connected, and a power source 8 as power supply means for forming a cathode at the article 1 is connected between the electrodes 6 and 7. Further, a supersonic vibration generator 9 for applying a supersonic vibration to the liquid 5 is disposed on the bottom of the tank 4. The article 1 is formed with a cathode by the power supplied from the power source 8 to generate foams 10 in the liquid 5, a foreign material 11 in the groove 2 is readily extruded to finely clean the article 1.

Description

【発明の詳細な説明】 （技術分野〕 本発明は、洗浄技術、特に、超高度の洗浄を行う技術に
関し、例えば、半導体装置の製ｉりにおいて、ウェハを
洗浄するのに使用してを効な技術に関する。Detailed Description of the Invention (Technical Field) The present invention relates to cleaning technology, particularly technology for ultra-high cleaning. related to technology.

Ｃ背景技術〕 半導体装置の製造において、ウェハを洗浄する場合、ウ
ェハを流水中に浸漬して洗浄することが、考えられる。C. Background Art] When cleaning a wafer in the manufacture of semiconductor devices, it is conceivable to immerse the wafer in running water for cleaning.

しかし、かかる洗浄技術においては、ウェハに形成され
た微細な濶溝内に残存する異物については充分に洗浄す
ることができないという問題点があることが本発明者に
よって明らかにされた。However, the inventor of the present invention has found that such a cleaning technique has a problem in that foreign matter remaining in the fine grooves formed on the wafer cannot be sufficiently cleaned.

なお、ウェハを流水により洗浄する技術を述べである例
としては、株式会社工業調査会発行［電子材料１９８２
年１１月号別冊」昭和５６年１１月１０日発行　Ｐ９５
〜Ｐ１０２、がある。An example of a technique for cleaning wafers with running water is published by Kogyo Kenkyukai Co., Ltd. [Electronic Materials 1982].
“November issue special issue” published November 10, 1980, P95
~P102, there is.

〔発明の目的〕[Purpose of the invention]

本発明の目的は、微細な深溝の内部についても充分に洗
浄することができる洗浄技術を提（Ｉｊすることにある
。An object of the present invention is to provide a cleaning technique that can sufficiently clean the inside of minute deep grooves.

本発明の前記ならびにその他の目的と新規な特徴は、本
明細書の記述および添付図面から明らかになるであろう
。The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

〔発明の概要〕[Summary of the invention]

本願において開示される発明のうち代表的なものの概要
を闇華に説明すれば、次の通りである。A brief overview of typical inventions disclosed in this application is as follows.

すなわち、被洗浄物を液体中に浸漬するとともに、被洗
浄物を陰極化することにより、電気分解による水素ガス
発泡の洗浄作用を利用して被洗浄物を洗浄するようにし
たものである。That is, the object to be cleaned is immersed in a liquid and the object to be cleaned is made cathodic, so that the object to be cleaned is cleaned using the cleaning action of hydrogen gas bubbling caused by electrolysis.

〔実施例〕〔Example〕

第１図は本発明の一実施例であるウェハ洗浄装置を示す
縦断面図、第２図は第１図の■部を示す拡大部分断面図
である。FIG. 1 is a longitudinal cross-sectional view showing a wafer cleaning apparatus according to an embodiment of the present invention, and FIG. 2 is an enlarged partial cross-sectional view showing the section (■) in FIG.

本実施例において、この洗浄装置はシリコン基板からな
るウェハ１を洗浄するものとして構成されている。被洗
浄物であるウェハ１の主面には、例えば金属酸化膜半導
体（ＭＯＳ）においてキャパシタを構成するための微細
な深溝２が回設されており、表面にはンリコン酸化膜、
シリコン窒化膜等からなる絶縁物層３が形成されている
。In this embodiment, this cleaning apparatus is configured to clean a wafer 1 made of a silicon substrate. The main surface of the wafer 1, which is the object to be cleaned, is provided with fine deep grooves 2 for configuring a capacitor in, for example, a metal oxide semiconductor (MOS).
An insulator layer 3 made of a silicon nitride film or the like is formed.

このウェハ洗浄装置はウェハ１を収容可能な水槽４を備
えており、水槽４には電気分解による陰極水素ガス発泡
作用を行う液体５が保持されている。液体５としては、
電気分解による陰極水素ガスの発泡作用のみを実質的に
行う程度に電解質を極微量に含んだ純水を使用するとよ
い。This wafer cleaning apparatus includes a water tank 4 capable of accommodating a wafer 1, and the water tank 4 holds a liquid 5 that performs a cathode hydrogen gas bubbling action by electrolysis. As liquid 5,
It is preferable to use pure water containing a very small amount of electrolyte to the extent that it substantially only performs the bubbling action of the cathode hydrogen gas by electrolysis.

液体５中には、プラチナ（ＰＬ）、金（Ａｕ）等のよう
な液体５に対して不溶な材料からなるアノードＴＬ極６
とカソードを極７とがそれぞれ配設されており、カソー
ド電極７はウェハ１に適当な手段により電気的に接続し
得るように構成されている０両電極６．７には電源８が
ウェハ１を陰極化し得るように電気的に接続されており
、これにより、電＃８はウェハ１を陰極化する給電手段
を構成している。水槽４の外側底部には超音波発生装置
９が、液体５中に超音波振動を付勢し得るように設備さ
れている。In the liquid 5, there is an anode TL pole 6 made of a material insoluble in the liquid 5, such as platinum (PL), gold (Au), etc.
A power source 8 is connected to the electrodes 6 and 7, and the cathode electrode 7 is configured to be electrically connected to the wafer 1 by suitable means. The wafer 1 is electrically connected to the wafer 1 so that the wafer 1 can be made into a cathode.Thereby, the electrode #8 constitutes a power supply means that makes the wafer 1 a cathode. At the outer bottom of the water tank 4, an ultrasonic generator 9 is installed so as to be able to apply ultrasonic vibrations into the liquid 5.

次に、使用方法並びに作用を説明する。Next, the method of use and effect will be explained.

被洗浄物であるウェハｌを液体５中に浸漬させるととも
に、ウェハｌにカソード電極７を電気的に接続させる０
次いで、電源８により両電極６．７間に通電するととも
に、超音波発生装置９により液体５中に超音波振動を付
勢する。The wafer l, which is the object to be cleaned, is immersed in the liquid 5, and the cathode electrode 7 is electrically connected to the wafer l.
Next, the power source 8 applies electricity between the electrodes 6 and 7, and the ultrasonic generator 9 applies ultrasonic vibrations to the liquid 5.

両電極６．７に電圧が印加されると、深溝２においてウ
ェハ１は液体５中に露出して電気的に接触しているため
、次式ｆｉ＋に示されているような反応により、深溝２
において、電気分解による水素ガスの発泡作用が起こる
。When a voltage is applied to both electrodes 6.7, since the wafer 1 is exposed to the liquid 5 in the deep groove 2 and is in electrical contact with it, the deep groove 2
In this process, hydrogen gas bubbles due to electrolysis.

２ＸＨ陽イオン＋２×電子−水素ガス・・・（１）第２
図に示されているように、深溝２の内部に発生した泡１
０は、次のような作用により、深溝２の内部の表面を洗
浄することになる。2XH cation + 2X electron - hydrogen gas...(1) Second
As shown in the figure, bubbles 1 generated inside the deep groove 2
0 cleans the inner surface of the deep groove 2 by the following action.

ｉｌ＋　　発泡は深溝２の内部において液体５を攪拌し
、エツチング時に付着したポリマ残渣等のような異物１
１を押し流す。il+ Foaming stirs the liquid 5 inside the deep groove 2 and removes foreign substances 1 such as polymer residues attached during etching.
Push away 1.

＋２１　　泡１０は竿の表面で溝内のコンクミ不一ンヨ
ンを捕捉すること（トラ、プ効果）により、溝２外に移
送する。+21 The foam 10 is transferred to the outside of the groove 2 by capturing the contaminants in the groove on the surface of the rod (trap effect).

（３）泡ｌＯは深溝２の表面に付着した異物１１を剥離
させる。(3) The bubbles 1O peel off the foreign matter 11 attached to the surface of the deep groove 2.

（４）　　泡１０は潰れる際や浮き上がる際に異物１１
を機械的に破壊し、異物を剥離、捕捉、移送され易くす
る。(4) When the bubble 10 collapses or rises, foreign matter 11
Mechanically destroys foreign objects, making them easier to peel off, capture, and transport.

ところで、発生した水素ガスの泡１０がウェハ１の深溝
２の表面に付着し続けていると、発泡作用が抑制されて
しまうことが、考えられる。By the way, if the generated hydrogen gas bubbles 10 continue to adhere to the surface of the deep grooves 2 of the wafer 1, it is conceivable that the bubbling effect will be suppressed.

本実施例においては、超音波振動発生装置９を付設し、
超音波振動を液体５中に付勢することにより、発生した
泡１０を深／ｌｌ＄２の表面から液体５中に可及的速や
かに離脱させるようにしている。In this embodiment, an ultrasonic vibration generator 9 is attached,
By applying ultrasonic vibrations to the liquid 5, the generated bubbles 10 are caused to separate from the surface at a depth of 1/1$2 into the liquid 5 as quickly as possible.

すなわち、超音波振動エネルギを付勢されると、泡１０
は深溝２から強制的に引き離される。That is, when energized with ultrasonic vibration energy, the bubbles 10
is forcibly separated from the deep groove 2.

このようにして泡が発生と同時に離脱すると、深溝２の
表面は液体５中に直ちに接触することになるため、電気
分解による発泡作用が休みなく連続して効果的に起こる
ことになる。さらに、超音波振動は、泡１０に機械的エ
ネルギを付与するため、発泡によるｎ；１記（１）〜（
４）の洗浄作用を助長さ−する働きも行うことになる。In this way, when bubbles are generated and removed at the same time, the surface of the deep grooves 2 comes into immediate contact with the liquid 5, so that the foaming action by electrolysis occurs continuously and effectively. Furthermore, since the ultrasonic vibration imparts mechanical energy to the foam 10, n;
It also has the function of promoting the cleaning action in 4).

しかも、検音波振動はそれ自体によっても洗浄作用を行
う。Furthermore, the sonic vibration itself also performs a cleaning action.

泡を深溝の表面から可及的速やかに離脱させて発泡を促
進させる手段として、電気化学的反応を利用する手段が
ある。As a means of promoting foaming by separating the bubbles from the surface of the deep grooves as quickly as possible, there is a means of utilizing an electrochemical reaction.

例えば、ナトリウム（Ｎａ）やカリウム（Ｋａ）等の陽
イオンを極微量含む電解液を液体５として使用すること
により、水素ガスの泡１０の肥大化を抑制し、イオン的
に中性化した泡ＩＯを呼び寄せるようにして引き離すこ
とができる。For example, by using an electrolytic solution containing minute amounts of cations such as sodium (Na) and potassium (Ka) as the liquid 5, the enlargement of the hydrogen gas bubbles 10 is suppressed, and the bubbles become ionically neutralized. You can pull them apart by calling IO.

なお、深ａ２の内部において発泡が効果的に起こるよう
に、ウェハｌの他の表面は絶縁物層により被覆すること
が望ましい。Note that it is desirable that the other surfaces of the wafer 1 be covered with an insulating layer so that foaming can occur effectively inside the depth a2.

〔効果〕〔effect〕

（１）被洗浄物を液体中に浸漬するとともに、被洗浄物
を陰極化することにより、電気分解による水素ガス発泡
の洗浄作用を利用して被洗浄物を洗浄することができる
ため、微細な深溝等の内部までも充分に洗浄することが
できる。(1) By immersing the object to be cleaned in a liquid and turning it into a cathode, the object can be cleaned using the cleaning action of hydrogen gas bubbles caused by electrolysis. Even the inside of deep grooves etc. can be thoroughly cleaned.

（２）超音波振子力を付勢するごとに、１、す、　’ｔ
１２をｌ；を浄表面から速やかに離脱させることができ
るため、発泡を促進することができるとともに、発泡に
伴う洗浄作用を助長することができる。(2) Each time the ultrasonic pendulum force is energized, 1, s, 't
Since 12 and 1; can be quickly separated from the clean surface, foaming can be promoted and the cleaning action accompanying the foaming can be promoted.

以上本発明者によってなされた発明を実施例に基づき具
体的に説明したが、本発明は前記実施例に限定されるも
のではなく、その要旨を逸脱しない範囲で種々変更可能
であることはいうまでもなし・。Although the invention made by the present inventor has been specifically explained above based on Examples, it goes without saying that the present invention is not limited to the Examples and can be modified in various ways without departing from the gist thereof. Nothing.

例えば、水槽は液体を停止させて貯留するものに限らず
、流れを有するものでもよい。For example, the water tank is not limited to one that stops and stores liquid, but may be one that has a flow.

液体としての純水は、被洗浄物に悪影響を与えない程度
の不純物を含んでもよい。Pure water as a liquid may contain impurities to the extent that they do not adversely affect the object to be cleaned.

〔利用分野〕[Application field]

以上の説明では主として本発明者によってなされた発明
をその背景となった利用分野であるウェハの洗浄に適用
した場合について説明したが、それに限定されるもので
はなく、マスク等の洗浄等にも適用することができる。In the above explanation, the invention made by the present inventor was mainly applied to cleaning of wafers, which is the background application field, but the invention is not limited to this, and can also be applied to cleaning of masks etc. can do.

【図面の簡単な説明】 第１図は本発明の一実施例であるウェハ洗浄装置を示す
縦断面図、 第２図は第１図の■部を示す拡大部分断面図である。 １・・・ウェハ（被洗浄物）、２・・・深溝、３・・・
絶縁物層、４・・・水槽、５・・・液体。 ６・・・アノード電極、７・・・カソード電極、８・・
・電源（給電手段）、９・　・超音波振動発生装置、１
０・・・泡、１１・・・異物。 第　　１　　図 第　　２　　図BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal cross-sectional view showing a wafer cleaning apparatus according to an embodiment of the present invention, and FIG. 2 is an enlarged partial cross-sectional view showing the section ■ in FIG. 1... Wafer (object to be cleaned), 2... Deep groove, 3...
Insulator layer, 4...water tank, 5...liquid. 6... Anode electrode, 7... Cathode electrode, 8...
・Power source (power supply means), 9. ・Ultrasonic vibration generator, 1
0...Bubble, 11...Foreign substance. Figure 1 Figure 2

Claims (1)

【特許請求の範囲】 １、電気分解による陰極水素ガス発泡作用を行う液体を
保持する水槽と、液中に浸漬された被洗浄物を陰極化さ
せる給電手段とを備えている洗浄装置。 ２、被洗浄物が、深溝を有するウェハであることを特徴
とする特許請求の範囲第１項記載の洗浄装置。 ３、液体が、純水であることを特徴とする特許請求の範
囲第１項記載の洗浄装置。 ４、液体が、発生した泡の被洗浄物からの離脱を促進さ
せる成分を含んでいることを特徴とする特許請求の範囲
第１項記載の洗浄装置。 ５、電気分解による陰極水素ガス発泡作用を行う液体を
保持する水槽と、液中に浸漬された被洗浄物を陰極化さ
せる給電手段と、液中に対して超音波振動を付勢する超
音波発生手段とを備えている洗浄装置。[Scope of Claims] 1. A cleaning device comprising a water tank that holds a liquid that performs a cathode hydrogen gas foaming action by electrolysis, and a power supply means that cathodes an object to be cleaned immersed in the liquid. 2. The cleaning apparatus according to claim 1, wherein the object to be cleaned is a wafer having deep grooves. 3. The cleaning device according to claim 1, wherein the liquid is pure water. 4. The cleaning device according to claim 1, wherein the liquid contains a component that promotes separation of generated foam from the object to be cleaned. 5. A water tank that holds a liquid that performs a cathodic hydrogen gas foaming action by electrolysis, a power supply means that cathodes the object to be cleaned immersed in the liquid, and an ultrasonic wave that applies ultrasonic vibrations to the liquid. A cleaning device comprising a generating means.
JP19466684A 1984-09-19 1984-09-19 Cleaning device Granted JPS6173333A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP19466684A JPS6173333A (en) 1984-09-19 1984-09-19 Cleaning device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP19466684A JPS6173333A (en) 1984-09-19 1984-09-19 Cleaning device

Publications (2)

Publication Number Publication Date
JPS6173333A true JPS6173333A (en) 1986-04-15
JPH0566725B2 JPH0566725B2 (en) 1993-09-22

Family

ID=16328284

Family Applications (1)

Application Number Title Priority Date Filing Date
JP19466684A Granted JPS6173333A (en) 1984-09-19 1984-09-19 Cleaning device

Country Status (1)

Country Link
JP (1) JPS6173333A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1993008931A2 (en) * 1991-11-08 1993-05-13 Tadahiro Ohmi System for supplying ultrapure water and method of washing substrate, and system for producing ultrapure water and method of producing ultrapure water
KR100748480B1 (en) * 2007-06-27 2007-08-10 한국기계연구원 Ultrasonic device for cleaning and ultrasonic cleaning system using the same
KR100827618B1 (en) * 2006-05-11 2008-05-07 한국기계연구원 Ultrasonic device for cleaning and ultrasonic cleaning system using the same
JP2009172162A (en) * 2008-01-24 2009-08-06 Olympus Medical Systems Corp Washing instrument for endoscope
JP2011091403A (en) * 2009-10-21 2011-05-06 Imec Method and device for cleaning semiconductor substrate

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1993008931A2 (en) * 1991-11-08 1993-05-13 Tadahiro Ohmi System for supplying ultrapure water and method of washing substrate, and system for producing ultrapure water and method of producing ultrapure water
WO1993008931A3 (en) * 1991-11-08 1993-06-10 Tadahiro Ohmi System for supplying ultrapure water and method of washing substrate, and system for producing ultrapure water and method of producing ultrapure water
US5589005A (en) * 1991-11-08 1996-12-31 Ohmi; Tadahiro System for supplying ultrapure water and method of washing substrate, and system for producing ultrapure water and method of producing ultrapure water
KR100827618B1 (en) * 2006-05-11 2008-05-07 한국기계연구원 Ultrasonic device for cleaning and ultrasonic cleaning system using the same
KR100748480B1 (en) * 2007-06-27 2007-08-10 한국기계연구원 Ultrasonic device for cleaning and ultrasonic cleaning system using the same
JP2009172162A (en) * 2008-01-24 2009-08-06 Olympus Medical Systems Corp Washing instrument for endoscope
JP2011091403A (en) * 2009-10-21 2011-05-06 Imec Method and device for cleaning semiconductor substrate

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Publication number Publication date
JPH0566725B2 (en) 1993-09-22

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