JPH03169014A - Circulating filtration apparatus - Google Patents

Abstract

PURPOSE:To prevent a produced foreign body from adhering to a wafer again by using a simple constitution by a method wherein at least a return route of a circulation system of an etching solution is formed as two or more systems and one blowoff port out of them is faced with the upper part of a side face of an etching tank. CONSTITUTION:In a route of a circulation system, two or more systems of return routes at least after a filter 7 are installed; a solution blowoff port 12 of one return route 11 is installed at a side face of an etching tank 4 near the upper part of a wafer 1 which is immersed in a solution. Foreign bodies which stay near the upper part of the wafer 1 are made to flow out quickly in a transverse direction; the foreign bodies which adhere to the wafer 1 again are reduced when the wafer 1 is taken in and out. Thereby, it is possible to largely suppress the foreign bodies which adhere to the wafer 1 again, and a high yield of LSI can be realized.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 この発明は、半導体製造装置で、特に溶液にて半導体（
ウエハ）を洗浄、エッチングする循環枦過装置に関する
ものである． 〔従来の技術〕 第３図は従来のこの種の循環ｒ過装置を示すもので、ウ
エハ１はカセット２に収納された状態でエッチング槽４
内の溶液３に浸漬され、エッチングまたは洗浄される．
この時発生した反応物または異物はエッチング槽４を矢
印Ａのようにオーバーフローし、溶液受け皿５にたまり
、矢印Ｂのように循環往路８を通ってボンプ６に吸引さ
れる．このようにして吸引された溶液は、次にフィルタ
ー７によりｒ過され、浄化された溶液は、矢印Ｃのよう
に循環復路９を通ってエッチング槽下部より再びエッチ
ング槽に供給される．この循環機構により、常に溶液は
清浄度を保つことができる構造となっている． 〔発明が解決しようとする課題〕 この従来の循環枦過装置では、１系統の循環経路しか配
置されておらず、従ってウエハを溶液に浸漬中に発生し
た異物１０は、完全に循環枦過されるまでに、しばらく
の時間を要するため、ウェハ引き上げ時は溶液上部にま
だ異物が浮遊している。[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a semiconductor manufacturing apparatus, particularly for manufacturing a semiconductor (
This relates to a circulation device for cleaning and etching wafers. [Prior Art] FIG. 3 shows a conventional circulation device of this type, in which a wafer 1 is stored in a cassette 2 and transferred to an etching bath 4.
It is immersed in solution 3 in the water and etched or cleaned.
Reactants or foreign matter generated at this time overflow the etching tank 4 as shown by arrow A, accumulate in the solution receiving tray 5, and are sucked into the pump 6 through the circulation path 8 as shown by arrow B. The solution sucked in this way is then filtered through a filter 7, and the purified solution is supplied to the etching tank again from the bottom of the etching tank through a circulation return path 9 as shown by arrow C. This circulation mechanism ensures that the solution remains clean at all times. [Problems to be Solved by the Invention] In this conventional circulation and filtration device, only one circulation path is arranged, so that the foreign matter 10 generated while the wafer is immersed in the solution is completely circulated and filtrated. Because it takes some time for the solution to dissolve, foreign matter is still floating on top of the solution when the wafer is pulled up.

このためウエハ表面に異物が再付着し、ＬＳＩの歩留り
の低下や欠陥の発生原因となっていた．この発明は上記
のような問題点を解消するためになされたもので、簡単
な構戒で発生異物のウエハへの再付着を防止できる装置
を得ることを目的とする． 〔課題を解決するための手段〕 この発明に係る循環枦過装置は、エッチング溶液の循環
系の少なくともその復路経路を２系統以上にするととも
に、その内の一方の吹き出し口をエッチング槽側面の上
部に臨ませるようにしたものである． 〔作用〕 この発明において、エッチング槽側面上部に設けられた
復路系は、エッチング時に発生した異物を、すばやく横
方向に流し、ウエハ上部の溶液を清浄に保つ働きをなし
、これによりウエハの出し入れ時でもウエハ表面に異物
が再付着することが抑制され、歩留りの向上に寄与する
． 〔実施例〕 以下、この発明の実施例を図について説明する．第１図
において、上記従来例と異なるところは、循環系の経路
で、少なくともフィルタ７以降の復路を２系統以上設け
、この復路の一方＋１の溶液吹き出し口１２を溶液中に
浸漬されているウエハ上部付近のエッチング槽側面に設
けることにより、ウエハ上部付近に滞留している異物を
すばやく横方向へ流し出し、もってウエハ出し入れ時に
ウエハに再付着する異物を大きく減少させるようにした
ものである．その他の構戒は従来例のものと同様につき
同一符号を付して説明を省略する．なおこの時、エッチ
ング槽４の側面の高さは、溶液吹き出し口側側面より反
対側の側面高さの方を低くすることが望ましい．また側
面の溶液吹き出し口から吹き出される溶液の流速は、充
分に早いことが望ましいことはいうまでもない．さらに
これらの作用を確実に実現するためには、第２図に示し
た如く、循環系を独立に制御できるように２系統以上併
設するとよい． 〔発明の効果〕 以上のよう仁この発明によれば、循環枦過装置の溶液循
環の復路側を２系統以上設ける構造としたことにより、
ウエハヘ再付着する異物を大きく抑制することができ、
ＬＳＩの高歩留り化に大きく寄与する効果がある．As a result, foreign matter reattaches to the wafer surface, causing a decrease in LSI yield and the occurrence of defects. This invention was made to solve the above-mentioned problems, and the purpose is to provide a device that can prevent generated foreign matter from re-adhering to a wafer with simple precautions. [Means for Solving the Problems] The circulation device according to the present invention has at least two return routes in the etching solution circulation system, and one of the return routes is connected to the upper part of the side surface of the etching tank. It was designed to make it appear like this. [Function] In the present invention, the return path system provided at the upper side of the etching tank serves to quickly flow away foreign matter generated during etching in the horizontal direction and keep the solution above the wafer clean, thereby making it easier to clean the solution when loading and unloading the wafer. However, this prevents foreign matter from re-adhering to the wafer surface, contributing to improved yields. [Example] Hereinafter, an example of the present invention will be explained with reference to the drawings. In FIG. 1, the difference from the conventional example is that the circulation system has at least two return routes after the filter 7, and one of the return routes +1 solution outlet 12 is connected to the wafer immersed in the solution. By installing it on the side of the etching tank near the top, it quickly flushes out foreign matter that has accumulated near the top of the wafer laterally, thereby greatly reducing the amount of foreign matter that re-attaches to the wafer when the wafer is taken in and out. Other construction precepts are the same as those of the conventional example, so the same symbols are given and explanations are omitted. At this time, it is desirable that the height of the side surface of the etching bath 4 is lower than that of the side surface on the side opposite to the solution outlet. It goes without saying that it is desirable that the flow rate of the solution blown out from the side solution outlet be sufficiently fast. Furthermore, in order to reliably achieve these effects, it is recommended to install two or more systems so that the circulatory system can be controlled independently, as shown in Figure 2. [Effects of the Invention] As described above, according to the present invention, by having a structure in which two or more systems are provided on the return path side of the solution circulation of the circulation filtration device,
Foreign matter re-adhering to the wafer can be greatly suppressed,
This has the effect of greatly contributing to higher yields of LSI.

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

第１図はこの発明の一実施例を示す配置断面図、第２図
はこの発明の他の実施例を示す配置断面図、第３図は従
来の循環Ｐ過装置を示す配置断面図である． 図中、１はウエハ、２はカセット、３はエッチング溶液
、４はエッチング槽、６は循環ポンプ、７はフィルタ、
９．１１は循環復路、１２は循環吹き出し口である．Fig. 1 is a sectional view showing an arrangement of one embodiment of the present invention, Fig. 2 is a sectional view showing another embodiment of the invention, and Fig. 3 is a sectional view showing a conventional circulation P passing device. ．． In the figure, 1 is a wafer, 2 is a cassette, 3 is an etching solution, 4 is an etching bath, 6 is a circulation pump, 7 is a filter,
9.11 is a circulation return path, and 12 is a circulation outlet.

Claims (1)

【特許請求の範囲】[Claims] 　エッチング槽内の溶液に半導体を浸漬した状態で、上
記容液を上記槽上部へオーバーフローさせるとともに、
このオーバーフローした溶液をポンプにて吸引し循環さ
せるようにした循環ろ過装置において、上記溶液の循環
系の少なくともその復路経路を複数系統にするとともに
、その内の一方の溶液吹き出し口を上記エッチング槽側
面の上部に配置したことを特徴とする循環ろ過装置。With the semiconductor immersed in the solution in the etching tank, the solution is allowed to overflow to the top of the tank, and
In a circulation filtration device that sucks and circulates this overflowing solution with a pump, the solution circulation system has at least a plurality of return routes, and one of the solution outlet ports is connected to the side surface of the etching tank. A circulation filtration device characterized by being placed on the top of the.