JP2007141888A - Cleaning liquid and cleaning method for removing polyimide film - Google Patents
Cleaning liquid and cleaning method for removing polyimide film Download PDFInfo
- Publication number
- JP2007141888A JP2007141888A JP2005329264A JP2005329264A JP2007141888A JP 2007141888 A JP2007141888 A JP 2007141888A JP 2005329264 A JP2005329264 A JP 2005329264A JP 2005329264 A JP2005329264 A JP 2005329264A JP 2007141888 A JP2007141888 A JP 2007141888A
- Authority
- JP
- Japan
- Prior art keywords
- cleaning
- polyimide film
- aqueous solution
- oxidizing agent
- inorganic salt
- 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.)
- Pending
Links
Landscapes
- Cleaning By Liquid Or Steam (AREA)
- Cleaning Or Drying Semiconductors (AREA)
Abstract
Description
本発明は基材面のポリイミド膜を除去する技術に関し、とくに半導体製造工程で使用されポリイミドが蒸着した石英器具表面のポリイミド膜を除去するのに好適な洗浄液および洗浄方法に関する。 The present invention relates to a technique for removing a polyimide film on a substrate surface, and more particularly, to a cleaning liquid and a cleaning method suitable for removing a polyimide film on a surface of a quartz device used in a semiconductor manufacturing process and deposited with polyimide.
半導体製造における成膜工程やエッチング工程においては、石英器具を備えた装置が使用される。たとえば、ＣＶＤ（Chemical Vapor Deposition）装置では、石英からなる処理チャンバー内に石英チューブが立設され、この石英チューブ内に半導体ウエハを保持した石英ボートが配置される。 In a film forming process and an etching process in semiconductor manufacturing, an apparatus provided with a quartz instrument is used. For example, in a CVD (Chemical Vapor Deposition) apparatus, a quartz tube is erected in a processing chamber made of quartz, and a quartz boat holding a semiconductor wafer is placed in the quartz tube.
このＣＶＤ装置では、ＣＶＤ法によって半導体ウエハに蒸着される膜と同一材質の蒸着膜が石英器具の露出表面に形成される。ＣＶＤ法によって蒸着される膜が石英器具と同じ材質であるＳｉＯ2膜以外の膜である場合、石英器具表面に蒸着膜が形成された状態で加熱、冷却などの温度変化が伴う処理が繰り返されると、熱膨張係数の違いから石英器具と蒸着膜の間に引張応力が生じ、この引張応力により石英器具表面の蒸着膜が剥がれ、パーティクル発生の原因となる。このため、蒸着膜が形成された石英器具は、洗浄により蒸着膜を除去する必要がある。 In this CVD apparatus, a vapor deposition film made of the same material as that deposited on the semiconductor wafer is formed on the exposed surface of the quartz apparatus by the CVD method. When the film deposited by the CVD method is a film other than the SiO 2 film, which is the same material as the quartz device, a process involving a temperature change such as heating and cooling is repeated with the deposited film formed on the surface of the quartz device. Due to the difference in thermal expansion coefficient, a tensile stress is generated between the quartz device and the vapor deposition film, and the vapor deposition film on the surface of the quartz device is peeled off by this tensile stress, which causes generation of particles. For this reason, it is necessary to remove a vapor deposition film by washing | cleaning the quartz instrument in which the vapor deposition film was formed.
このような石英器具の蒸着膜の一つとしてポリイミド膜がある。ポリイミドは、半導体装置の保護膜や絶縁膜を形成するのに使用されるもので、保護膜や絶縁膜は塗布法によって形成される場合もあるが、層間絶縁膜などのような薄膜はＣＶＤ法によって形成される。ＣＶＤ法によって層間絶縁膜を形成する場合は、石英器具の露出表面にもポリイミドが蒸着するので、この石英器具に蒸着したポリイミド膜を洗浄により除去する必要がある。 One of the vapor deposition films of such a quartz instrument is a polyimide film. Polyimide is used to form a protective film or insulating film for semiconductor devices. The protective film or insulating film may be formed by a coating method, but a thin film such as an interlayer insulating film is formed by a CVD method. Formed by. When the interlayer insulating film is formed by the CVD method, polyimide is deposited on the exposed surface of the quartz device, so it is necessary to remove the polyimide film deposited on the quartz device by washing.
従来、半導体製造に関連したポリイミド膜の除去のための洗浄剤としては、特許文献１および特許文献２に記載されているような有機溶剤と、特許文献３および特許文献４に記載されているような無機系の洗浄液とがある。特許文献１および特許文献２に記載の有機溶剤は、基板の裏面などに付着した不要のポリイミド前駆体を除去するための有機溶剤であり、特許文献３に記載の洗浄液は、基板にポリイミド樹脂配向膜を印刷した後の印刷版に付着したポリイミド樹脂を除去するための無機塩水溶液であり、特許文献４に記載の洗浄剤は、基板に形成したポリイミド樹脂配向膜を剥離するための水酸化カリウム水溶液である。
特許文献１および特許文献２に記載の有機溶剤は、高価であるうえに、換気や防爆などの作業環境の整備や廃液処理にコストがかかるという問題がある。特許文献３および特許文献４に記載の洗浄液は、有機溶剤の問題点に鑑みて、無機系の洗浄液を採用し、無機系の洗浄液の洗浄力の不足分を超音波振動の付加や紫外線の照射で補うようにしたものである。 The organic solvents described in Patent Literature 1 and Patent Literature 2 are expensive and have a problem that costs are required for maintenance of working environments such as ventilation and explosion prevention and waste liquid treatment. In view of the problem of organic solvents, the cleaning liquids described in Patent Document 3 and Patent Document 4 employ inorganic cleaning liquids, and the lack of cleaning power of inorganic cleaning liquids is applied with ultrasonic vibration or ultraviolet irradiation. This is what I made up for.
ところで、特許文献１および特許文献２に記載の洗浄において除去されるポリイミド前駆体は、基板に塗布されたポリイミド前駆体である。また特許文献３および特許文献４に記載の洗浄において除去されるポリイミド膜は、基板に印刷または塗布されたポリイミド膜である。このように印刷または塗布により形成されたポリイミド膜であれば、無機系の洗浄液であっても超音波振動の付加や紫外線の照射で洗浄力の不足分を補うことにより、ある程度の洗浄効果を得ることはできる。 By the way, the polyimide precursor removed in the washing | cleaning of patent document 1 and patent document 2 is a polyimide precursor apply | coated to the board | substrate. Moreover, the polyimide film removed in the washing | cleaning of patent document 3 and patent document 4 is a polyimide film printed or apply | coated to the board | substrate. If the polyimide film is formed by printing or coating in this way, even if it is an inorganic cleaning liquid, a certain degree of cleaning effect can be obtained by supplementing the lack of cleaning power by adding ultrasonic vibration or irradiating ultraviolet rays. I can.
しかし前記したような、ＣＶＤ法によってポリイミド膜を形成する工程で石英器具に蒸着したポリイミド膜の除去の場合は、ポリイミドが高温で蒸着重合されたものであるので、無機塩水溶液に浸漬するだけでは、ポリイミド膜の除去完了までに約１ヶ月という長期間を要する。特許文献３に記載の洗浄においては洗浄効果をあげるための補助手段として超音波振動を付加しているが、石英器具に対して超音波振動を付加することは、石英器具を破損するおそれがあるので採用することはできず、また特許文献３に記載のような紫外線の照射を行っても、高温で蒸着重合されたポリイミドの除去には長時間を要し、いずれの場合もポリイミドを短時間で除去することは難しい。 However, in the case of removing the polyimide film deposited on the quartz apparatus in the process of forming the polyimide film by the CVD method as described above, the polyimide is vapor-deposited and polymerized at a high temperature. It takes a long time of about one month to complete the removal of the polyimide film. In the cleaning described in Patent Document 3, ultrasonic vibration is added as an auxiliary means for improving the cleaning effect, but adding ultrasonic vibration to a quartz instrument may damage the quartz instrument. Therefore, even if irradiation with ultraviolet rays as described in Patent Document 3 is performed, it takes a long time to remove the polyimide polymerized by vapor deposition at a high temperature. It is difficult to remove with.
このような無機塩水溶液の洗浄能力上の問題は石英器具に蒸着したポリイミド膜の除去の場合に限らず、たとえば、プリント配線板の製造工程で、ポリイミドフィルムの表面にメッキや接着した金属皮膜をエッチングし、樹脂と積層して回路基板を形成した後にポリイミドフィルムを洗浄除去するのに無機塩水溶液が使用されているが、このような場合にも無機塩水溶液による洗浄には長時間を要しており、洗浄能力の向上が望まれている。
本発明の解決すべき課題は、無機系の洗浄液を使用して基材面のポリイミド膜を除去するにあたり、洗浄能力を高めるアルカリ水溶液の組成を検討し、とくに石英器具に蒸着したポリイミド膜のような洗浄除去に長時間を要するポリイミド膜を効率よく除去する技術を確立することにある。
Such problems with the cleaning ability of the aqueous inorganic salt solution are not limited to the removal of the polyimide film deposited on the quartz device. For example, in the manufacturing process of a printed wiring board, a metal film plated or adhered to the surface of the polyimide film is used. An aqueous solution of inorganic salt is used to clean and remove the polyimide film after etching and laminating with a resin to form a circuit board. Even in such a case, cleaning with the aqueous solution of inorganic salt takes a long time. Therefore, improvement of cleaning ability is desired.
The problem to be solved by the present invention is to examine the composition of an alkaline aqueous solution that enhances the cleaning ability when removing the polyimide film on the substrate surface using an inorganic cleaning solution, and in particular, like a polyimide film deposited on a quartz apparatus. The purpose is to establish a technique for efficiently removing a polyimide film that requires a long time for proper cleaning and removal.
本発明者らは、石英器具およびその他の耐アルカリ性の基材に付着したポリイミド膜を洗浄除去する方法について鋭意検討した結果、無機塩水溶液と酸化剤水溶液を併用した洗浄液がポリイミド膜を効率的に除去できることを知見し、本発明を完成するに至ったものである。 As a result of intensive studies on a method for cleaning and removing a polyimide film adhered to a quartz device and other alkali-resistant substrates, the present inventors have found that a cleaning solution using a combination of an inorganic salt aqueous solution and an oxidizing agent aqueous solution can efficiently remove the polyimide film. The inventors have found that they can be removed, and have completed the present invention.
すなわち、本発明に係る洗浄液は、耐アルカリ性の基材に付着したポリイミド膜を除去する洗浄液であって、必須成分として無機塩と酸化剤を含む水溶液からなることを特徴とする。 That is, the cleaning liquid according to the present invention is a cleaning liquid that removes the polyimide film adhered to the alkali-resistant substrate, and is characterized by comprising an aqueous solution containing an inorganic salt and an oxidizing agent as essential components.
また、本発明に係る洗浄方法は、耐アルカリ性の基材に付着したポリイミド膜を除去する洗浄方法であって、必須成分として無機塩と酸化剤を含む水溶液からなる洗浄液に前記ポリイミドが付着した基材を浸漬することを特徴とする。 Further, the cleaning method according to the present invention is a cleaning method for removing a polyimide film attached to an alkali-resistant substrate, wherein the polyimide is attached to a cleaning solution comprising an aqueous solution containing an inorganic salt and an oxidizing agent as essential components. It is characterized by dipping the material.
ここで、前記無機塩としては、水溶液がアルカリ性を呈する無機塩類を使用することができ、なかでも水酸化ナトリウム、水酸化カリウムを使用することが望ましい。水酸化ナトリウム、水酸化カリウムは、安価で入手しやすく、化学的に安定しており、水溶液が強アルカリ性であり、使用後はｐＨ調整のみで排水することができるという利点がある。また前記酸化剤としては、過硫酸塩類、過酸化物、硝酸塩類、亜硝酸塩類、過塩素酸塩類、過塩素酸、塩素酸塩類、亜塩素酸塩類、次亜塩素酸塩類、次亜塩素酸のいずれか１種以上を使用することができ、なかでも過硫酸ナトリウム、過硫酸カリウム、過硫酸アンモニウムを使用することが望ましい。過硫酸ナトリウム、過硫酸カリウム、過硫酸アンモニウムは、安価であり、毒性が低く、酸化力の持続性があるので長時間の洗浄に使用でき、ガスを発生しないという利点がある。 Here, as the inorganic salt, inorganic salts in which the aqueous solution exhibits alkalinity can be used, and it is desirable to use sodium hydroxide or potassium hydroxide. Sodium hydroxide and potassium hydroxide are advantageous in that they are inexpensive, easily available, chemically stable, the aqueous solution is strongly alkaline, and can be drained only by pH adjustment after use. Examples of the oxidizing agent include persulfates, peroxides, nitrates, nitrites, perchlorates, perchloric acid, chlorates, chlorites, hypochlorites, hypochlorite. Any one or more of these can be used, and among them, sodium persulfate, potassium persulfate, and ammonium persulfate are preferably used. Sodium persulfate, potassium persulfate, and ammonium persulfate are advantageous in that they are inexpensive, have low toxicity, have a long oxidizing power, and can be used for long-time cleaning, and do not generate gas.
耐アルカリ性の基材に付着したポリイミド膜を除去するのに、アルカリ性の無機塩と酸化剤を含むアルカリ水溶液からなる洗浄液を使用することにより、酸化剤がポリイミド膜の組成を変化させ、あるいはポリイミド膜を酸化分解し、アルカリ水溶液によるポリイミド膜の加水分解と溶解を促進させて、無機塩だけの水溶液の場合に比してポリイミド膜の洗浄効果を格段に高める。たとえば、ポリイミドが蒸着した石英器具の洗浄の場合、洗浄液中にポリイミドが蒸着した石英器具を浸漬すると、酸化剤がポリイミドのイミド間の結合を分解し、表面のポリイミド膜を壊しながらアルカリ水溶液が内部に染み込んでいき、アルカリ水溶液が石英の表面に到達後、ポリイミド膜と石英の結合を分解し引き剥がすことにより、短時間で石英器具に蒸着したポリイミド膜の除去が行われる。
さらに無機系の洗浄液であるので、有機溶剤使用上の作業環境や廃液処理の問題がなく、また、無機塩と酸化剤を併用することによる洗浄力の向上で、超音波振動の付加や紫外線の照射などの補助手段を講じる必要もなくなる。
To remove the polyimide film adhering to the alkali-resistant substrate, the oxidant changes the composition of the polyimide film by using a cleaning solution comprising an alkaline aqueous solution containing an alkaline inorganic salt and an oxidizing agent, or the polyimide film Is oxidatively decomposed to promote hydrolysis and dissolution of the polyimide film with an alkaline aqueous solution, and the cleaning effect of the polyimide film is remarkably enhanced as compared with an aqueous solution containing only an inorganic salt. For example, in the case of cleaning a quartz device on which polyimide is deposited, if the quartz device on which polyimide is deposited is immersed in a cleaning solution, the oxidizing agent decomposes the bonds between the polyimide imides and breaks the polyimide film on the surface while the alkaline aqueous solution is inside. After the alkaline aqueous solution reaches the surface of the quartz, the polyimide film deposited on the quartz apparatus is removed in a short time by decomposing and peeling the bond between the polyimide film and the quartz.
In addition, since it is an inorganic cleaning solution, there are no problems in the working environment or waste liquid treatment when using organic solvents, and the use of an inorganic salt and an oxidizing agent improves the cleaning power. There is no need to take auxiliary measures such as irradiation.
水溶液中の無機塩と酸化剤の濃度および配合割合、洗浄液の温度を適正な範囲に設定することにより、良好な作業環境のもとで十分な洗浄効果が得られる。また、洗浄液と被洗浄材との間に相対的な動きを付与することによっても洗浄効果を高めることができる。 By setting the concentration and blending ratio of the inorganic salt and the oxidizing agent in the aqueous solution and the temperature of the cleaning liquid to an appropriate range, a sufficient cleaning effect can be obtained under a good working environment. The cleaning effect can also be enhanced by providing a relative movement between the cleaning liquid and the material to be cleaned.
本発明を実施するためには、被洗浄材の最大寸法に応じた大きさの洗浄タンクと、洗浄タンク内の洗浄液を振とうあるいはバブリングするための装置、および洗浄液の循環装置ならびに洗浄液を準備する。 In order to carry out the present invention, a cleaning tank having a size corresponding to the maximum dimension of the material to be cleaned, a device for shaking or bubbling the cleaning liquid in the cleaning tank, a cleaning liquid circulation device, and a cleaning liquid are prepared. .
洗浄液の主剤である水溶性の無機塩としては、水溶液がアルカリ性を呈する無機塩類を使用する。水溶液がアルカリ性を呈する無機塩類には、アルカリ金属水酸化物、アルカリ金属炭酸塩類、アルカリ金属炭酸水素塩類、アンモニアなどがあるが、そのなかでも、水酸化ナトリウムまたは水酸化カリウムを使用するのが望ましい。水酸化ナトリウムと水酸化カリウムは、化学的に安定しており、水溶液が強アルカリ性であり、使用後はｐＨ調整のみで廃水することができるという利点がある。また、入手が容易でかつ安価であるので、洗浄コストの低減に有効である。 As the water-soluble inorganic salt which is the main component of the cleaning liquid, inorganic salts whose aqueous solution exhibits alkalinity are used. Inorganic salts in which the aqueous solution exhibits alkalinity include alkali metal hydroxides, alkali metal carbonates, alkali metal hydrogen carbonates, ammonia, etc. Among them, it is desirable to use sodium hydroxide or potassium hydroxide. . Sodium hydroxide and potassium hydroxide have the advantage that they are chemically stable, the aqueous solution is strongly alkaline, and can be drained only by pH adjustment after use. Moreover, since it is easy to obtain and inexpensive, it is effective in reducing the cleaning cost.
また、同じく洗浄液の主剤である酸化剤としては、過硫酸塩類、過酸化物、硝酸塩類、亜硝酸塩類、過塩素酸塩類、過塩素酸、塩素酸塩類、亜塩素酸塩類、次亜塩素酸塩類、次亜塩素酸のいずれか１種以上を使用する。これらに含まれる化合物は数多くあるが、そのなかで重金属を含む化合物は人体や環境に悪影響を与える可能性があるので、重金属を含む化合物は使用しないほうがよい。アルカリ性無機塩類とともに併用してポリイミド膜の洗浄に効果的な化合物としては、過硫酸ナトリウム、過硫酸カリウム、過硫酸アンモニウム、過酸化水素、次亜塩素酸ナトリウム、次亜塩素酸カリウム、次亜塩素酸カルシウムなどが挙げられる。これらの化合物は、強力な酸化剤であるが人体への影響が少なく、かつ安価に入手できるので、作業の安全性やコスト低減に有効である。なかでも、コスト、洗浄効果、溶液の安定性、作業性、安全性など総合的観点からみて、過硫酸ナトリウム、過硫酸カリウム、過硫酸アンモニウムを使用するのが望ましい。 Similarly, the oxidizing agent that is the main component of the cleaning liquid includes persulfates, peroxides, nitrates, nitrites, perchlorates, perchloric acid, chlorates, chlorites, hypochlorous acid. Use at least one of salts and hypochlorous acid. Although there are many compounds contained in these, compounds containing heavy metals may adversely affect the human body and the environment, so it is better not to use compounds containing heavy metals. Compounds effective for cleaning polyimide membranes in combination with alkaline inorganic salts include sodium persulfate, potassium persulfate, ammonium persulfate, hydrogen peroxide, sodium hypochlorite, potassium hypochlorite, hypochlorous acid Examples include calcium. These compounds are powerful oxidizers, but have little influence on the human body and can be obtained at low cost. Therefore, these compounds are effective for work safety and cost reduction. Of these, sodium persulfate, potassium persulfate, and ammonium persulfate are preferably used from the comprehensive viewpoints such as cost, cleaning effect, solution stability, workability, and safety.
水溶液中の無機塩と酸化剤の濃度は、以下の説明においてすべて質量％で表すものとする。無機塩の濃度は１．０〜２０．０％の範囲が好ましい。無機塩の濃度が１．０％より低いと、酸化剤の存在のもとでも、ポリイミド膜の十分な除去効果が得られず、２０．０％を超えるとアルカリ性の溶液が蒸気となって分散しやすくなり、作業環境の悪化につながるので、上記範囲が適当である。より望ましい濃度の範囲は５．０〜１１．０％である。また、酸化剤の濃度は１．０〜３０．０％の範囲が好ましい。酸化剤の濃度が１．０％より低いと、無機塩の洗浄効果を高める作用が不足し、３０．０％を超えて添加してもその効果は飽和するので、上記範囲が適当である。より望ましい濃度の範囲は３．０〜１５．０％である。 The concentrations of the inorganic salt and the oxidizing agent in the aqueous solution are all expressed in mass% in the following description. The concentration of the inorganic salt is preferably in the range of 1.0 to 20.0%. If the concentration of the inorganic salt is lower than 1.0%, a sufficient removal effect of the polyimide film cannot be obtained even in the presence of the oxidizing agent, and if it exceeds 20.0%, the alkaline solution is dispersed as vapor. The above range is appropriate because it leads to a worse working environment. A more desirable concentration range is 5.0 to 11.0%. The concentration of the oxidizing agent is preferably in the range of 1.0 to 30.0%. If the concentration of the oxidizing agent is lower than 1.0%, the effect of enhancing the cleaning effect of the inorganic salt is insufficient, and even if added over 30.0%, the effect is saturated, so the above range is appropriate. A more desirable concentration range is 3.0 to 15.0%.
無機塩と酸化剤の配合割合は、それぞれの濃度が上記範囲のもとで、無機塩：酸化剤が１：１／１０〜１：２０の範囲であることが好ましい。無機塩に対する酸化剤の割合が１／１０より低いと、アルカリ性無機塩が酸化剤の還元を促進して酸化力は一時的に高まるが、酸化力は短期間で急速に低下してしまうので好ましくない。無機塩に対する酸化剤の割合が２０倍より高くなってもその効果は飽和するので、上記範囲が適当である。より望ましい割合は１：１／５〜１：１０の範囲である。 The blending ratio of the inorganic salt and the oxidizing agent is preferably in the range of 1: 1/10 to 1:20 of the inorganic salt: oxidizing agent, with the respective concentrations being within the above range. When the ratio of the oxidizing agent to the inorganic salt is lower than 1/10, the alkaline inorganic salt promotes the reduction of the oxidizing agent to temporarily increase the oxidizing power, but the oxidizing power is preferably decreased rapidly in a short period. Absent. Since the effect is saturated even when the ratio of the oxidizing agent to the inorganic salt is higher than 20 times, the above range is appropriate. A more desirable ratio is in the range of 1: 1/5 to 1:10.
上記の濃度および配合割合の範囲のなかで、無機塩と酸化剤のそれぞれの化合物の組み合わせによって最適な範囲は多少異なる。たとえば、無機塩と酸化剤の組み合わせとして、水酸化ナトリウムまたは水酸化カリウムと、過硫酸ナトリウム、過硫酸カリウム、過硫酸アンモニウムのいずれかを組み合わせて使用した場合の、無機塩と酸化剤の最適な濃度と配合割合の範囲は、無機塩の濃度は２．０〜２０．０％、より望ましくは４．０〜８．０％、酸化剤の濃度は１．０〜３０．０％、より望ましくは１．０〜１０．０％の範囲であり、配合割合は無機塩：酸化剤＝１：１／５〜１：５、より望ましくは１：１／５〜１：２の範囲である。 Among the above ranges of concentration and blending ratio, the optimum range differs somewhat depending on the combination of each compound of inorganic salt and oxidizing agent. For example, the optimum concentration of inorganic salt and oxidizing agent when using sodium hydroxide or potassium hydroxide in combination with either sodium persulfate, potassium persulfate, or ammonium persulfate as a combination of inorganic salt and oxidizing agent The blending ratio ranges from 2.0 to 20.0%, more preferably from 4.0 to 8.0%, and more preferably from 1.0 to 30.0%, more preferably from 0.02 to 0.03%. The range is 1.0 to 10.0%, and the blending ratio is inorganic salt: oxidizer = 1: 1/5 to 1: 5, more preferably 1: 1/5 to 1: 2.
無機塩と酸化剤を溶解させる水としては、超純水、純水、蒸留水、水道水、地下水のいずれでもよいが、石英器具その他の基材への影響をできる限り除くためには、純水、蒸留水を使用するのが好ましい。いずれの水を使用するにしても、水中に不可避的に含有される無機物、有機物は微量であるので、洗浄液の洗浄効果には影響しない。 The water that dissolves the inorganic salt and the oxidizing agent may be ultrapure water, pure water, distilled water, tap water, or ground water. It is preferable to use water or distilled water. Whichever water is used, the amount of inorganic and organic substances inevitably contained in the water is so small that it does not affect the cleaning effect of the cleaning liquid.
洗浄時における洗浄液の温度は、室温程度以上であれば無機塩と酸化剤の水への溶解度の点からも洗浄効果の点からもとくに問題はないが、洗浄効果をより高めて洗浄時間を短縮するためには、４０℃以上に加熱するのが好ましい。ただし、洗浄液の温度を高くしすぎると作業環境が悪化するので、作業場所の隔離や局所排気装置などの排気設備の設置を行う必要がある。安全性を考慮すると加熱温度は８０℃以下とするのがよい。また、洗浄効果を高めるために、洗浄液を振とうあるいはバブリングなどの補助手段を講じて洗浄液を対流させ、洗浄液と被洗浄材との間に相対的な動きを付与するのも有効である。また、無機塩と酸化剤を含む水溶液に界面結成剤を添加してもよい。 If the temperature of the cleaning solution at the time of cleaning is about room temperature or higher, there is no particular problem in terms of the solubility of the inorganic salt and the oxidizing agent in water and the cleaning effect, but the cleaning effect is further improved and the cleaning time is shortened. In order to do so, it is preferable to heat to 40 ° C. or higher. However, if the temperature of the cleaning liquid is too high, the working environment is deteriorated. Therefore, it is necessary to isolate the working place and install exhaust equipment such as a local exhaust device. In consideration of safety, the heating temperature is preferably 80 ° C. or lower. In order to enhance the cleaning effect, it is also effective to provide a relative movement between the cleaning liquid and the material to be cleaned by providing auxiliary means such as shaking or bubbling the cleaning liquid to convect the cleaning liquid. Further, an interfacial binder may be added to an aqueous solution containing an inorganic salt and an oxidizing agent.
本発明の効果を確認するために、各種の洗浄液と洗浄条件で洗浄試験を行った。
〔試験例１〕
従来の洗浄液として、ジメチルホルムアミド、５０％ヒドラジン水和物溶液、５％ＮａＯＨ水溶液の３種の洗浄液、および、本発明に係る洗浄液である無機塩と酸化剤を含む水溶液として、（５％ＮａＯＨ＋１５％Ｈ2Ｏ2）水溶液（洗浄液１）を作成し、石英ウエハに蒸着したポリイミド膜の洗浄試験を行った。サンプルはポリイミドが蒸着した２００ｍｍ径石英ウエハを約５ｃｍ2に分割した小片で、５０ｍｌの各洗浄液に室温で３日間浸漬し、超音波洗浄を行ってポリイミド膜の剥離状況を観察した。試験結果を表１に示す。
In order to confirm the effect of the present invention, cleaning tests were performed with various cleaning solutions and cleaning conditions.
[Test Example 1]
As conventional cleaning solutions, three types of cleaning solutions, dimethylformamide, 50% hydrazine hydrate solution, and 5% NaOH aqueous solution, and an aqueous solution containing an inorganic salt and an oxidizing agent that are cleaning solutions according to the present invention (5% NaOH + 15% An aqueous solution of H 2 O 2 ) (cleaning solution 1) was prepared, and a cleaning test was performed on the polyimide film deposited on the quartz wafer. The sample was a small piece obtained by dividing a 200 mm diameter quartz wafer on which polyimide was vapor-deposited into about 5 cm 2 , immersed in 50 ml of each cleaning solution at room temperature for 3 days, and subjected to ultrasonic cleaning to observe the peeling state of the polyimide film. The test results are shown in Table 1.
従来の洗浄液のうち５０％ヒドラジン水和物溶液は３日間でポリイミド膜を除去することができたが、ジメチルホルムアミドは３日間では完全に除去することができず、５％ＮａＯＨ水溶液は３日間ではほとんど洗浄効果がみられなかった。一方、本発明に係る洗浄液１では、２日間でポリイミド膜を完全に除去することができた。 Among the conventional cleaning solutions, the 50% hydrazine hydrate solution was able to remove the polyimide film in 3 days, but dimethylformamide could not be completely removed in 3 days, and the 5% NaOH aqueous solution in 3 days. There was almost no cleaning effect. On the other hand, with the cleaning liquid 1 according to the present invention, the polyimide film could be completely removed in two days.
〔試験例２〕
実際の洗浄時に超音波振動を付加すると石英器具が破損するおそれがあるので、超音波振動を付加しない状態での洗浄試験を行った。試験例１の５０％ヒドラジン水和物溶液と、本発明に係る洗浄液である無機塩と酸化剤を含む水溶液として、（１１％ＮａＯＨ＋１５％Ｈ2Ｏ2）水溶液（洗浄液２）および（１１％ＮａＯＨ＋１．５％Ｋ2Ｓ2Ｏ8）水溶液（洗浄液３）の、３種の洗浄液を作成し、石英ウエハに蒸着したポリイミド膜の洗浄試験を行った。サンプルは試験例１とは別のポリイミドが蒸着した２００ｍｍ径石英ウエハを約５ｃｍ2に分割した小片で、５０ｍｌの各洗浄液に４日間浸漬し、ポリイミド膜の剥離状況を観察した。試験開始後１日目は静置状態で洗浄を行っていたが、洗浄効果がみられなかったので２日目からは振とう装置に入れ、３日目からは装置内の温度を５０℃にして洗浄を行った。試験結果を表２に示す。
[Test Example 2]
Since the quartz instrument may be damaged if ultrasonic vibration is applied during actual cleaning, a cleaning test was performed without applying ultrasonic vibration. (11% NaOH + 15% H 2 O 2 ) aqueous solution (cleaning solution 2) and (11% NaOH + 1) as an aqueous solution containing the 50% hydrazine hydrate solution of Test Example 1 and the inorganic salt and oxidizing agent that are the cleaning solution according to the present invention. Three types of cleaning liquids (.5% K 2 S 2 O 8 ) aqueous solution (cleaning liquid 3) were prepared, and the cleaning test of the polyimide film deposited on the quartz wafer was performed. The sample was a small piece obtained by dividing a 200 mm-diameter quartz wafer deposited with polyimide different from Test Example 1 into about 5 cm 2 , immersed in 50 ml of each cleaning solution for 4 days, and the state of peeling of the polyimide film was observed. On the 1st day after the start of the test, washing was carried out in a stationary state. However, since the cleaning effect was not observed, it was put into a shaking apparatus from the 2nd day, and the temperature inside the apparatus was changed to 50 ° C from the 3rd day. And washed. The test results are shown in Table 2.
超音波振動を付加しない状態での洗浄の場合は、従来の洗浄液としては洗浄効果の高い５０％ヒドラジン水和物溶液でも、４日間ではほとんど洗浄効果がみられなかった。一方、本発明に係る洗浄液２および洗浄液３では、４日間でポリイミド膜を完全に除去することができた。 In the case of washing without applying ultrasonic vibration, even a 50% hydrazine hydrate solution having a high washing effect as a conventional washing liquid showed almost no washing effect in 4 days. On the other hand, with the cleaning liquid 2 and the cleaning liquid 3 according to the present invention, the polyimide film could be completely removed in 4 days.
〔試験例３〕
洗浄条件の検討のために、静置、振とう、バブリングの比較試験と温度の比較試験を行った。洗浄液は試験例２の洗浄液２と洗浄液３を用い、試験例１，２とは別のポリイミドが蒸着した２００ｍｍ径石英ウエハを約５ｃｍ2に分割した小片を５０ｍｌの各洗浄液にそれぞれの条件下で浸漬し、ポリイミド膜が完全に除去されるまでの時間を測定した。試験結果を表３に示す。
[Test Example 3]
In order to examine the washing conditions, a comparative test of standing, shaking and bubbling and a comparative test of temperature were performed. As the cleaning liquid, the cleaning liquid 2 and the cleaning liquid 3 of Test Example 2 were used, and a 200 mm diameter quartz wafer on which polyimide different from Test Examples 1 and 2 was vapor-deposited was divided into about 5 cm 2 into 50 ml of each cleaning liquid under the respective conditions. Immersion was performed, and the time until the polyimide film was completely removed was measured. The test results are shown in Table 3.
表３の結果からわかることは、洗浄効果を高めるためには、まず洗浄液の温度を上げること、つぎに洗浄液を対流させることである。とくに酸化剤としてＨ2Ｏ2を用いた場合は、加熱により反応速度が高まり、洗浄所要時間が大幅に短縮される。 As can be seen from the results in Table 3, in order to increase the cleaning effect, first, the temperature of the cleaning liquid is increased, and then the cleaning liquid is convected. In particular, when H 2 O 2 is used as the oxidizing agent, the reaction rate is increased by heating, and the time required for washing is greatly reduced.
〔試験例４〕
洗浄液として、（６％ＮａＯＨ＋１．５％Ｋ2Ｓ2Ｏ8）水溶液（洗浄液４）、（６％ＮａＯＨ＋１．５％Ｎａ2Ｓ2Ｏ8）水溶液（洗浄液５）、（６％ＮａＯＨ＋１．５％（ＮＨ4）2Ｓ2Ｏ8）水溶液（洗浄液６）の３種の水溶液を用いて、洗浄液を更新せずに繰返し利用した洗浄試験を行った。サンプルは試験例１〜３とは別のポリイミドが蒸着した２００ｍｍ径石英ウエハを約５ｃｍ2に分割した小片で、洗浄液を４０℃で振とうし、新たなサンプルごとにポリイミド膜が完全に除去されるまでの時間を測定した。試験結果を表４に示す。
[Test Example 4]
(6% NaOH + 1.5% K 2 S 2 O 8 ) aqueous solution (cleaning solution 4), (6% NaOH + 1.5% Na 2 S 2 O 8 ) aqueous solution (cleaning solution 5), (6% NaOH + 1.5%) Using three types of aqueous solutions of (NH 4 ) 2 S 2 O 8 ) (cleaning solution 6), a cleaning test was repeatedly used without renewing the cleaning solution. The sample is a small piece obtained by dividing a 200 mm diameter quartz wafer with a polyimide vapor deposition different from Test Examples 1 to 5 cm 2 into about 5 cm 2 , and the cleaning liquid is shaken at 40 ° C., and the polyimide film is completely removed for each new sample. The time until completion was measured. The test results are shown in Table 4.
無機塩と併用する酸化剤として使用した過硫酸カリウム、過硫酸ナトリウム、過硫酸アンモニウムの３種の化合物は、洗浄効果に関してはほぼ同等であると考えられる。ただし、過硫酸カリウムは水への溶解度が低いので洗浄液の製造に時間がかかり、高濃度溶液の製造が困難であること、および、過硫酸アンモニウムは金属とアンモニア錯体を形成し結晶化する可能性があることから、この３種の化合物のなかでは、過硫酸ナトリウムの使用が最も適しているといえる。 The three compounds, potassium persulfate, sodium persulfate, and ammonium persulfate, used as the oxidizing agent in combination with the inorganic salt are considered to be substantially equivalent with respect to the cleaning effect. However, since potassium persulfate has low solubility in water, it takes time to produce a cleaning solution, making it difficult to produce a high-concentration solution, and ammonium persulfate may form an ammonia complex with a metal and crystallize. Therefore, among these three compounds, it can be said that the use of sodium persulfate is most suitable.
〔試験例５〕
無機塩としての水酸化ナトリウムと酸化剤としての過硫酸ナトリウムの濃度による洗浄効果の影響について調査した。同時に洗浄力の目安となる洗浄液の酸化還元電位の測定を行った。水酸化ナトリウムと過硫酸ナトリウムの濃度の組み合わせは、（２％ＮａＯＨ＋１．５％Ｎａ2Ｓ2Ｏ8）水溶液（洗浄液７）、（６％ＮａＯＨ＋１．５％Ｎａ2Ｓ2Ｏ8）水溶液（洗浄液８）、（６％ＮａＯＨ＋３．０％Ｎａ2Ｓ2Ｏ8）水溶液（洗浄液９）、（６％ＮａＯＨ＋５．０％Ｎａ2Ｓ2Ｏ8）水溶液（洗浄液１０）の４種である。試験要領は試験例４と同じである。試験結果を表５および表６に示す。
[Test Example 5]
The effect of cleaning effect on the concentration of sodium hydroxide as inorganic salt and sodium persulfate as oxidizing agent was investigated. At the same time, the oxidation-reduction potential of the cleaning liquid, which is a measure of the cleaning power, was measured. The combination of the concentrations of sodium hydroxide and sodium persulfate was (2% NaOH + 1.5% Na 2 S 2 O 8 ) aqueous solution (cleaning solution 7), (6% NaOH + 1.5% Na 2 S 2 O 8 ) aqueous solution (cleaning solution 8), (6% NaOH + 3.0% Na 2 S 2 O 8 ) aqueous solution (cleaning solution 9), and (6% NaOH + 5.0% Na 2 S 2 O 8 ) aqueous solution (cleaning solution 10). The test procedure is the same as in Test Example 4. The test results are shown in Tables 5 and 6.
表５および表６からわかるように、水酸化ナトリウム、過硫酸ナトリウムともに、濃度が高いほど洗浄時間が短縮され、また、洗浄処理量が増加することが確認された。ただし水酸化ナトリウムの濃度は、作業環境の悪化と石英への影響の点からはあまり高濃度にしないほうがよい。酸化還元電位は処理量が増加するほど減少（酸化力が低下）し、それに伴い洗浄力も衰えた。 As can be seen from Tables 5 and 6, it was confirmed that as both the concentrations of sodium hydroxide and sodium persulfate were increased, the cleaning time was shortened and the cleaning treatment amount was increased. However, the concentration of sodium hydroxide should not be too high in view of the deterioration of the working environment and the effect on quartz. The oxidation-reduction potential decreased as the amount of treatment increased (oxidation power decreased), and the cleaning power decreased accordingly.
以上、石英に蒸着したポリイミド膜の洗浄除去を中心にして説明したが、本発明に係る洗浄技術は、石英に蒸着したポリイミド膜の洗浄除去に限らず、半導体製造工程その他の工程で耐アルカリ性の基材に付着したポリイミド膜の洗浄除去に適用して極めて効果的な洗浄液および洗浄方法である。 As described above, the cleaning and removal of the polyimide film deposited on the quartz has been mainly described. However, the cleaning technique according to the present invention is not limited to the cleaning and removal of the polyimide film deposited on the quartz, and the alkali resistance in the semiconductor manufacturing process and other processes. This is a cleaning solution and cleaning method that are extremely effective when applied to cleaning and removal of a polyimide film adhered to a substrate.
Claims (6)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2005329264A JP2007141888A (en) | 2005-11-14 | 2005-11-14 | Cleaning liquid and cleaning method for removing polyimide film |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2005329264A JP2007141888A (en) | 2005-11-14 | 2005-11-14 | Cleaning liquid and cleaning method for removing polyimide film |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2007141888A true JP2007141888A (en) | 2007-06-07 |
Family
ID=38204455
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2005329264A Pending JP2007141888A (en) | 2005-11-14 | 2005-11-14 | Cleaning liquid and cleaning method for removing polyimide film |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2007141888A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010269374A (en) * | 2009-05-19 | 2010-12-02 | Adeka Corp | Stabilized ammonium persulfate aqueous solution, composition for chemical machinery polishing and chemical machinery polishing method |
| JP2015182012A (en) * | 2014-03-24 | 2015-10-22 | エアコン丸洗い株式会社 | Cleaning method of grease filter |
| WO2022024820A1 (en) * | 2020-07-29 | 2022-02-03 | 東洋紡株式会社 | Production method for flexible electronic device |
-
2005
- 2005-11-14 JP JP2005329264A patent/JP2007141888A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010269374A (en) * | 2009-05-19 | 2010-12-02 | Adeka Corp | Stabilized ammonium persulfate aqueous solution, composition for chemical machinery polishing and chemical machinery polishing method |
| JP2015182012A (en) * | 2014-03-24 | 2015-10-22 | エアコン丸洗い株式会社 | Cleaning method of grease filter |
| WO2022024820A1 (en) * | 2020-07-29 | 2022-02-03 | 東洋紡株式会社 | Production method for flexible electronic device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5196134A (en) | Peroxide composition for removing organic contaminants and method of using same | |
| CN101452824B (en) | Wet-chemistry semiconductor-chip treatment method | |
| WO2011074601A1 (en) | Composition for etching ruthenium-based metal and method for preparing same | |
| SG129274A1 (en) | Cleaaning solution and cleaning process using the solution | |
| WO2006029160A3 (en) | Copper processing using an ozone-solvent solution | |
| JPH10242107A (en) | Improved method of cleaning microelectronics circuit board | |
| TW201932588A (en) | Treatment liquid for semiconductor wafers, which contains hypochlorite ions | |
| TWI604090B (en) | Etching method | |
| JP2008106354A (en) | Metal removing solution and metal removing method using the same | |
| JP2016092340A (en) | Cleaning method and device for substrate | |
| CN112997278A (en) | Composition for removing ruthenium | |
| JPH08316187A (en) | Washing method | |
| JP2007141888A (en) | Cleaning liquid and cleaning method for removing polyimide film | |
| JP2633083B2 (en) | Peroxide composition for removing organic pollutants and method of using same | |
| JP2008205490A (en) | Cleaning composition for device substrate and method of cleaning and cleaning device using the cleaning composition | |
| JP4535232B2 (en) | Titanium or titanium alloy etchant | |
| JP2006210857A (en) | Cleaning liquid composition for removal of impurity, and impurity removal method using the composition | |
| KR100676684B1 (en) | Method of Clearance of Scale Using Chlorite | |
| JP2716126B2 (en) | Slime control method | |
| JPWO2019167971A1 (en) | Alumina protective liquid, a protective method, and a method for manufacturing a semiconductor substrate having an alumina layer using the same. | |
| EP0574858B1 (en) | Inorganic oxidant compositions for removing contaminants | |
| WO2006125369A1 (en) | Composition for removing photoresist layer and method for using it | |
| CN113201409A (en) | Cleaning composition of motor PCB soldering flux, preparation method, use method and application thereof | |
| JPH08124888A (en) | Method for cleaning semiconductor substrate with ozone | |
| JP5365031B2 (en) | Cleaning method for semiconductor manufacturing equipment parts |