JP3962468B2 - Cleaning composition - Google Patents

Description

（式中、Ｒ ¹ は水素原子、炭素原子数１〜１８の炭化水素基又は炭素原子数１〜１８のアシル基を示す。Ｒ ² は水素原子又はメチル基を示す。ＡＯはエチレンオキサイド及び／又はプロピレンオキサイドを示す。ｍは１〜１００の整数を示す。）で示される化合物を、モノマー成分Ｂとし、該モノマー成分Ｂを全モノマー成分の使用量の５〜７０モル％使用して得られる、重量平均分子量が５００〜１５万のポリカルボン酸化合物を含有してなる、半導体基板用又は半導体素子用洗浄剤組成物、
〔２〕 前記〔１〕記載の洗浄剤組成物を用いて洗浄する半導体基板又は半導体素子の洗浄方法、
に関するものである。
【００１０】
【発明の実施の形態】
本発明の洗浄剤組成物及び洗浄方法は、シリコンウエハ、化学半導体のウエハ、液晶パネルにおけるガラスパネル等の半導体基板に対して、及びかかる基板上に形成される半導体素子に対して適用される。
【００１１】
１．洗浄剤組成物
本発明の半導体基板用又は半導体素子用洗浄剤組成物は、アクリル酸、メタクリル酸及びマレイン酸からなる群より選ばれる少なくとも１種をモノマー成分（「モノマー成分Ａ」とする。）とし、該モノマー成分を全モノマー成分の使用量の２０モル％以上用いて得られる、重量平均分子量が５００〜１５万のポリカルボン酸化合物を含有してなる。前記ポリカルボン酸化合物を含有する洗浄剤組成物は、半導体基板及び半導体素子上の微粒子汚れの洗浄性に特に優れ、かつ使用時の泡立ちが少なく、洗浄作業性にも優れるものである。
【００１２】
モノマー成分Ａの総使用量は、水溶性の低下による微粒子汚れの洗浄性の悪化を防止する観点から、全モノマー成分の使用量の２０モル％以上が好ましく、５０モル％以上がより好ましく、８０％以上が特に好ましい。
【００１３】
本発明におけるポリカルボン酸化合物としては、微粒子除去性の観点から、全モノマー成分のうちのアクリル酸とマレイン酸の占める割合が７０モル％以上のものがより好ましい。その中でも、アクリル酸／マレイン酸のモル比が９／１〜５／５の場合が特に好ましい。
【００１４】
前記ポリカルボン酸化合物の重量平均分子量は、充分な微粒子除去性を得る観点から、５００以上であり、１０００以上がより好ましい。凝集性が現れ微粒子除去性が低下するのを防ぐ観点から、該重量平均分子量は１５万以下であり、１０万以下がより好ましく、５万以下が特に好ましい。
【００１５】
また、微粒子の洗浄性を向上させる観点から、モノマー成分として、さらに一般式（１）：
【００１６】
【化３】

【００１７】
（式中、Ｒ¹ は水素原子、炭素原子数１〜１８の炭化水素基又は炭素原子数１〜１８のアシル基を示す。Ｒ² は水素原子又はメチル基を示す。ＡＯはエチレンオキサイド及び／又はプロピレンオキサイドを示す。ｍは１〜１００の整数を示す。）で示される化合物（「モノマー成分Ｂ」とする。）を、全モノマー成分の使用量の５〜７０モル％使用することが好ましい。
【００１８】
前記一般式（１）において、Ｒ¹ は直鎖であってもよく分岐鎖であってもよく、飽和であってもよく不飽和であってもよく、芳香族環又は脂環族環を含んでいてもよく、含んでいなくてもよい。
【００１９】
前記炭素原子数１〜１８の炭化水素基の具体例としては、例えば、メチル基、エチル基、プロピル基、イソプロピル基、ブチル基、イソブチル基、ヘキシル基、オクチル基、２−エチルヘキシル基、デシル基、イソデシル基、トリデシル基、ステアリル基、オレイル基、ビニル基、ベンジル基、フェニルエチル基、フェニル基、メチルフェニル基、エチルフェニル基、イソブチルフェニル基、シクロヘキシル基等が挙げられる。前記炭素原子数１〜１８のアシル基の具体例としては、例えば、ホルミル基、アセチル基、プロピオニル基、ブチリル基、イソブチリル基、ヘキサノイル基、オクチノイル基等が挙げられる。これらのうち、Ｒ¹ は、微粒子除去性の観点から、水素原子又は炭素原子数１〜８の炭化水素基が好ましい。
【００２０】
前記一般式（１）において、ｍはＡＯの付加モル数を示し、微粒子の除去性の観点から１以上が好ましく、２以上がより好ましく、３以上が特に好ましい。また、微粒子の除去性の観点から１００以下が好ましく、４０以下がより好ましく、２０以下が特に好ましい。ｍが２以上の場合、ＡＯとしては、エチレンオキサイド単独からなるものでも良く、プロピレンオキサイド単独からなるものでも良く、両方が含まれていても良い。両方を含む場合、エチレンオキサイドとプロピレンオキサイドは、それぞれがランダムで結合していてもブロック状で結合していてもよいが、微粒子除去性の観点からは分子中のエチレンオキサイドとプロピレンオキサイドのモル比は９９／１〜５０／５０が好ましい。
【００２１】
モノマー成分Ｂの使用量は、微粒子の除去性の観点から、全モノマー成分の使用量の５モル％以上が好ましく、１０モル％以上がより好ましい。また、微粒子の除去性の観点から、モノマー成分Ｂの使用量は、全モノマー成分の使用量の７０モル％以下が好ましく、４０モル％以下がより好ましい。
【００２２】
ポリカルボン酸化合物のモノマー成分として、さらに他の化合物を用いても良い。具体的には、アクリル酸イソボルニル、アクリル酸メチル、アクリル酸エチル、アクリル酸プロピル、アクリル酸イソブチル、アクリル酸２−エチルヘキシル、アクリル酸アミノエチルエステル、アクリル酸４−ヒドロキシブチル、アクリル酸ラウリル、アクリルアミド、２−アクリルアミド−２−メチルプロパンスルホン酸等のアクリル酸の誘導体；メタクリル酸メチル、メタクリル酸エチル、メタクリル酸イソブチル、メタクリル酸２−エチルヘキシル、メタクリル酸アミノエチルエステル、メタクリル酸２−ヒドロキシエチル、メタクリル酸２−ヒドロキシプロピル、メタクリルアミド、２−メタクリルアミド２−メチルプロパンスルホン酸、メタクリル酸プロピル、メタクリル酸シクロヘキシル、メタクリル酸ベンジル、メタクリル酸ジメチルアミノエチル等のメタクリル酸の誘導体；エチレン、プロピレン、ブチレン、オクテン、ジイソブチレン、デセン等の炭素原子数２〜１８のオレフィン；スチレン、スチレン誘導体等が挙げられる。
【００２３】
前記のポリカルボン酸化合物の対イオンは特に限定されないが、分子量３００以下の含窒素系化合物が好ましい。例えば、アンモニア、アルキルアミン又はポリアルキルポリアミンにエチレンオキサイド、プロピレンオキサイド等を付加したモノエタノールアミン、ジエタノールアミン、トリエタノールアミン、メチルエタノールアミン、モノプロパノールアミン、ジプロパノールアミン、トリプロパノールアミン、メチルプロパノールアミン、モノブタノールアミン、アミノエチルエタノールアミン等のアミノアルコール類；テトラメチルアンモニウムハイドロオキサイド、コリン等の四級アンモニウム塩等が挙げられる。
【００２４】
本発明の洗浄剤組成物におけるポリカルボン酸化合物の量は、微粒子の除去性、低泡性等の特徴を発揮させる観点から、洗浄剤組成物の０．０１重量％以上が好ましく、０．１重量％以上がより好ましい。また、洗浄コスト、排水処理性等の観点から、１５重量％以下が好ましく、５重量％以下がより好ましい。
【００２５】
さらに本発明の洗浄剤組成物は、一般式（２）で示される化合物及び／又は一般式（３）で示される化合物を含有してもよい。かかる化合物を含有する洗浄剤組成物は、微粒子除去性、低泡性等を損なうことなく、半導体基板、半導体素子等に対する洗浄成分の湿潤浸透性、油性汚れに対する洗浄性等が向上し、特に油性汚れの付着した微粒子汚れに対し、優れた油性汚れ除去性微粒子除去性等が得られる。
【００２６】
前記一般式（２）で示される化合物とは、下式：
【００２７】
【化４】

【００２８】
（式中、Ｒ³ は水素原子、炭素原子数１〜５のアルキル基又は炭素原子数２〜５のアルケニル基を示す。ＡＯはエチレンオキサイド及び／又はプロピレンオキサイドを示す。Ｘは水素原子、炭素原子数１〜４のアルキル基又は炭素原子数１〜４のアシル基を示す。ｎは０〜２の整数を示す。ｐは１〜８の整数を示す。）で示される化合物である。
【００２９】
前記一般式（２）において、Ｒ³ 水素原子、炭素原子数１〜３のアルキル基又は炭素原子数２〜３のアルケニル基のものが洗浄性の観点から好ましい。また、Ｒ³ がアルキル基又はアルケニル基の場合、その炭素原子数が６以上のときは一般式（２）で示される化合物が発泡しやすくなるため好ましくない。（ＡＯ）の部分はエチレンオキサイドとプロピレンオキサイドをランダムで含んでいても良く、ブロックで含んでいても良い。Ｘは、水に対する溶解性、すすぎ性の観点から、Ｘがアルキル基又はアシル基の場合、炭素原子数は４以下の数が好ましい。Ｘは水素原子、炭素原子数１〜２のアルキル基又は炭素原子数１〜２のアシル基のものが洗浄性の観点からより好ましい。ｐはＡＯの付加モル数を示し、油性汚れに対する洗浄性の観点から１〜８の整数であり、好ましくは２〜６の整数である。
【００３０】
前記一般式（２）で示される化合物としては、具体的には、フェノール、メチルフェノール、イソプロピルフェノール、イソブチルフェノール、エチルフェノール、ビニルフェノール、ベンジルアルコール、メチルベンジルアルコール、エチルベンジルアルコール、イソプロピルベンジルアルコール、フェニルエチルアルコール等のフェノール類やアルコール類にエチレンオキサイド及び／又はプロピレンオキサイドが付加されたアルキレンオキサイド付加物等が挙げられる。さらに、かかるアルキレンオキサイド付加物に、例えばメチレンクロライド等のアルキレンクロライドや酢酸等を反応させ、Ｘの部分をアルキル基やアシル基にした化合物も、一般式（２）で示される化合物に含まれる。
【００３１】
一般式（３）で示される化合物とは、下式：
Ｒ⁵ −Ｏ−（ＡＯ）ｐ−Ｘ （３）
（式中、Ｒ⁵ は炭素原子数１〜６のアルキル基、炭素原子数２〜６のアルケニル基又は炭素原子数１〜６のアシル基を示す。ＡＯはエチレンオキサイド及び／又はプロピレンオキサイドを示す。Ｘは水素原子、炭素原子数１〜４のアルキル基又は炭素原子数１〜４のアシル基を示す。ｐは１〜８の整数を示す。）で示される化合物である。
【００３２】
一般式（３）において、発泡性を抑制する観点からＲ⁵ の炭素原子数は６以下が好ましい。また、Ｒ⁵ は炭素原子数３〜６のアルキル基又は炭素原子数３〜６のアルケニル基が洗浄性の観点からより好ましい。（ＡＯ）の部分はエチレンオキサイドとプロピレンオキサイドをランダムで含んでいても良く、ブロックで含んでいても良い。Ｘは水に対する溶解性、すすぎ性の観点から、Ｘがアルキル基又はアシル基の場合、炭素原子数は４以下の数が好ましい。Ｘは水素原子、炭素原子数１〜２のアルキル基又は炭素原子数１〜２のアシル基のものが洗浄性の観点からより好ましい。ｐは２〜６の整数が好ましい。
【００３３】
一般式（３）で示される化合物としては、具体的には、メタノール、エタノール、イソプロパノール、ブタノール、アミルアルコール、ヘキサノール、ビニルアルコール、１−プロペニルアルコール、１−ブテニルアルコール等のアルコールにエチレンオキサイド及び／又はプロピレンオキサイドが付加されたアルキレンオキサイド付加物等が挙げられる。さらに、かかるアルキレンオキサイド付加物に、例えばメチレンクロライド等のアルキレンクロライドや酢酸等を反応させ、Ｘの部分をアルキル基やアシル基にした化合物も、一般式（３）で示される化合物に含まれる。
【００３４】
一般式（２）で示される化合物及び一般式（３）で示される化合物は発泡性が少ないため、得られる洗浄剤組成物の使用時の発泡を抑えることができる。そのため、本発明の洗浄剤組成物は作業性や排水処理性が良好なものであり、好ましい。
【００３５】
ポリカルボン酸化合物に、一般式（２）で示される化合物及び／又は一般式（３）で示される化合物とを併用する場合、それぞれの化合物の特徴が相乗的に現れ、より良好な洗浄性が発揮される。
【００３６】
ここで、一般式（２）で示される化合物と一般式（３）で示される化合物との比率は特に限定されないが、重量比で、〔一般式（２）で示される化合物〕／〔一般式（３）で示される化合物〕が８／２〜２／８の範囲が好ましい。
【００３７】
さらに本発明の洗浄剤組成物は、非イオン界面活性剤を含有していても良い。かかる非イオン界面活性剤を含有する洗浄剤組成物は、半導体基板又は半導体素子に対する洗浄成分の浸透性、油性汚れに対する洗浄性がより良好なものであり、結果として微粒子の除去性、分散性等が向上されたものである。
【００３８】
かかる非イオン界面活性剤としては、例えば、下記の（ａ）群、（ｂ）群又は（ｃ）群の各群に含まれる化合物、さらには一般式（４）で示される化合物等が挙げられる。非イオン界面活性剤としては一種を単独で用いても良く、二種以上を混合して用いても良い。次に（ａ）群、（ｂ）群又は（ｃ）群の各群に含まれる化合物の具体例を示す。
【００３９】
（ａ）群：炭素原子数７〜２２の炭化水素基を有する直鎖又は分岐鎖の飽和又は不飽和のアルコールにエチレンオキサイド及び／又はプロピレンオキサイドが付加された化合物、炭素原子数１〜２２の炭化水素基を有する直鎖又は分岐鎖の飽和又は不飽和のアミンにエチレンオキサイド及び／又はプロピレンオキサイドが付加された化合物、並びに炭素原子数１〜２２の炭化水素基を有する直鎖又は分岐鎖の飽和又は不飽和の脂肪酸にエチレンオキサイド及び／又はプロピレンオキサイドが付加された化合物。
【００４０】
（ｂ）群：炭素原子数２〜１０の多価アルコールにエチレンオキサイド及び／又はプロピレンオキサイドが付加された化合物、炭素原子数２〜１０のポリアミンにエチレンオキサイド及び／又はプロピレンオキサイドが付加された化合物、並びに炭素原子数２〜１０の多価脂肪酸にエチレンオキサイド及び／又はプロピレンオキサイドが付加された化合物。
【００４１】
（ｃ）群：アルキルフェノール（但し、アルキル基の炭素原子数は６以上である。）にエチレンオキサイド及び／又はプロピレンオキサイドが付加された化合物、スチレン化フェノールにエチレンオキサイド及び／又はプロピレンオキサイドが付加された化合物、ベンジル化フェノールにエチレンオキサイド及び／又はプロピレンオキサイドが付加された化合物、並びにナフトールにエチレンオキサイド及び／又はプロピレンオキサイドが付加された化合物。
【００４２】
さらに、（ａ）群、（ｂ）群及び（ｃ）群に含まれる化合物に、例えば炭素原子数１〜４のアルキレンクロライドや炭素原子数１〜４の脂肪酸等を反応させ、その末端部分をアルキル基やアシル基にした化合物も、ここでいう非イオン界面活性剤に含まれる。
【００４３】
一般式（４）で示される化合物を含有してなる本発明の洗浄剤組成物は油性汚れの除去性が優れたものであり、特に油性汚れの付着した微粒子の除去性が良好なものである。
【００４４】
一般式（４）で示される化合物とは、
Ｒ⁷ −Ｏ−（ＡＯ）ｒ−Ｘ （４）
（式中、Ｒ⁷ は炭素原子数８〜１８のアルキル基、炭素原子数８〜１８のアルケニル基、炭素原子数８〜１８のアシル基又は炭素原子数１４〜１８のアルキルフェノール基を示す。ＡＯはエチレンオキサイド及び／又はプロピレンオキサイドを示す。Ｘは水素原子、炭素原子数１〜４のアルキル基又は炭素原子数１〜４のアシル基を示す。ｒは３〜３５の整数を示す。）で示される化合物である。
【００４５】
前記一般式（４）において、Ｒ⁷ は炭素原子数８〜１４のアルキル基、炭素原子数８〜１４のアルケニル基、炭素原子数８〜１４のアシル基又は炭素原子数１４〜１６のアルキルフェノール基が洗浄性の観点から好ましい。（ＡＯ）の部分はエチレンオキサイドとプロピレンオキサイドをランダムで含んでいても良く、ブロックで含んでいても良い。
【００４６】
Ｘは水素原子、炭素原子数１〜２のアルキル基又は炭素原子数１〜２のアシル基が好ましい。ｒは洗浄性の観点から６〜２５の整数がより好ましい。また、（ＡＯ）の部分がエチレンオキサイドとプロピレンオキサイドの比がモル比で９／１〜５／５の範囲のものは泡立ちが少なく好ましい。
【００４７】
前記一般式（４）で示される非イオン界面活性剤としては、具体的には、２−エチルヘキサノール、オクタノール、デカノール、イソデシルアルコール、トリデシルアルコール、ラウリルアルコール、ミリスチルアルコール、ステアリルアルコール、オレイルアルコール、オクチルフェノール、ノニルフェノール、ドデシルフェノール等のアルコール類、フェノール類等にエチレンオキサイド及び／又はプロピレンオキサイドを付加した化合物等が挙げられる。さらに、かかるアルキレンオキサイド付加物に、例えばメチレンクロライド等のアルキレンクロライド、酢酸等を反応させ、Ｘの部分をアルキル基やアシル基にした化合物も、一般式（４）で示される非イオン界面活性剤に含まれる。
【００４８】
また、一般式（２）で示される化合物、一般式（３）で示される化合物、非イオン界面活性剤といった成分が洗浄剤組成物に含有されている場合、洗浄剤組成物中のかかる成分の総含有量は特に限定されるものではなく、被洗浄物を洗浄する際にかかる本発明の洗浄剤組成物を適宜希釈して用いることができる。
【００４９】
本発明の洗浄剤組成物は、その洗浄目的に対応して、洗浄剤組成物のｐＨが適宜調整されても良い。金属不純物をより効果的に除去する観点から、本発明の洗浄剤組成物は酸性のものが好ましい。具体的には、塩酸、硫酸、硝酸、フッ酸、蟻酸及び酢酸からなる群より選ばれる少なくとも１種をさらに含有し、そのｐＨが０．１〜６の洗浄剤組成物が好ましい。この場合、洗浄剤組成物のｐＨは１〜３がより好ましい。
【００５０】
また、微粒子をより効果的に除去する観点からは、本発明の洗浄剤組成物はアルカリ性のものが好ましい。具体的には、アンモニア、アミノアルコール、テトラメチルアンモニウムハイドロオキサイド、コリン及び水酸化カリウムからなる群より選ばれる少なくとも１種をさらに含有し、そのｐＨが８〜１４の範囲の洗浄剤組成物が好ましい。この場合、洗浄剤組成物のｐＨは１０〜１３がより好ましい。
【００５１】
アミノアルコールとしては、例えば、モノエタノールアミン、ジエタノールアミン、トリエタノールアミン、メチルエタノールアミン、メチルジエタノールアミン、モノプロパノールアミン、ジプロパノールアミン、トリプロパノールアミン、メチルプロパノールアミン、メチルジプロパノールアミン、アミノエチルエタノールアミン等が挙げられる。かかるアミノアルコールは単独で用いても良く、二種以上を混合して用いても良い。
【００５２】
本発明の洗浄剤組成物は本発明の特性を損なわない範囲で、シリコン系の消泡剤やＥＤＴＡのようなキレート剤、アルコール類、グリコールエーテル類、防腐剤、酸化防止剤等を配合できる。
【００５３】
本発明の洗浄剤組成物は半導体素子や半導体基板の製造工程のいずれの工程で使用しても良い。例示すれば、シリコンウエハのラッピングやポリシング工程後の洗浄工程；半導体素子製造前の洗浄工程；半導体素子製造工程、例えば、レジスト現像後、ドライエッチング後、ウェットエッチング後、ドライアッシング後、レジスト剥離後、ＣＭＰ処理前後、ＣＶＤ処理前後等の洗浄工程；ＴＦＴ型液晶表示板等の半導体素子製造工程で使用することができる。
【００５４】
本発明の洗浄剤組成物は、上記の各成分を混合すること等により容易に調製することができる。
【００５５】
２．洗浄方法
本発明の洗浄方法は、本発明の洗浄剤組成物を用いて、半導体基板又は半導体素子を洗浄する方法である。本発明の洗浄剤組成物を用いて洗浄する際、１）ポリカルボン酸化合物、２）一般式（２）で示される化合物、３）一般式（３）で示される化合物、及び４）非イオン界面活性剤の総含有量が、微粒子除去性、洗浄性等の観点から０．００１〜２０重量％で洗浄を行うことが好ましく、０．０１〜２０重量％で洗浄を行うことがより好ましく、０．０５〜１０重量％で洗浄を行うことがさらに好ましく、０．１〜５．０重量％で洗浄を行うことが特に好ましい。
【００５６】
本発明に用いることのできる洗浄手段としては特に限定されるものではなく、、浸漬洗浄、揺動洗浄、スピンナー等の回転を利用した洗浄、パドル洗浄、気中又は液中スプレー洗浄及び超音波洗浄、ブラシ洗浄等の公知の手段を用いることができる。かかる洗浄手段は単独で実施しても良く、複数を組み合わせて実施しても良い。また、半導体基板又は半導体素子は、一回の洗浄操作で一枚ずつ洗浄しても良く、複数枚数を洗浄しても良い。また、洗浄の際に用いる洗浄槽の数は１つでも複数でも良い。洗浄時の洗浄剤組成物の温度は特に限定されるものではないが、２０〜１００℃の範囲が安全性、操業性の点で好ましい。
【００５７】
【実施例】
つぎに、本発明を実施例及びに基づいてさらに詳細に説明するが、本発明はかかる実施例等に限定されるものではない。
【００５８】
実施例１〜１９、比較例１〜４
１．汚染液の調製
２リットルのビーカーに研磨粒子及びシリコンウエハの摩耗粒子を想定したシリカ粒子（粒径０．５〜２μｍ）を、１５００ｍＬの超純水に２重量％となる量分散させ、汚染液（Ａ）を調製した。次に汚染液（Ａ）に機械油ミストを想定したオレイン酸ブチルエステルを１．０ｇ加え、汚染液（Ｂ）を調製した。
【００５９】
２．洗浄剤組成物・洗浄液の調製
表１及び表２に示す化合物を用いて、表３〜表５に示す組成（数値は重量％）の洗浄剤組成物を調製した。
【００６０】
【表１】

【００６１】
【表２】

【００６２】
【表３】

【００６３】
【表４】

【００６４】
【表５】

【００６５】
次いで、洗浄剤組成物を希釈して洗浄液（１）、洗浄液（２）及び洗浄液（３）を調製した。具体的には次の通りである。
【００６６】
（１）：洗浄剤組成物を純水で希釈後、アンモニア水又は塩酸でｐＨを７．５に調整して洗浄液を得た。得られた洗浄液における、洗浄剤組成物を構成する各成分の総含有量（重量％）は表６〜表１１に示される通りである。ここで総含有量が０重量％の洗浄液は、洗浄剤組成物を用いず、純水とアンモニア水でｐＨを７．５に調整したものである。このようにして調製された洗浄液を洗浄方法▲１▼で洗浄液（１）として使用した。
【００６７】
（２）：ｐＨを１１にしたアンモニア水に、洗浄剤組成物を添加して洗浄液を得た。得られた洗浄液における、洗浄剤組成物を構成する各成分の総含有量（重量％）は表６〜表１１に示される通りである。このようにして調製された洗浄液を洗浄方法▲２▼で洗浄液（２）として使用した。
【００６８】
（３）：ｐＨを２の塩酸水溶液に、洗浄剤組成物を添加して洗浄液を得た。得られた洗浄液における、洗浄剤組成物を構成する各成分の総含有量（重量％）は表６〜表１１に示される通りである。このようにして調製された洗浄液を洗浄方法▲３▼で洗浄液（３）として使用した。
【００６９】
【表６】

【００７０】
【表７】

【００７１】
【表８】

【００７２】
【表９】

【００７３】
【表１０】

【００７４】
【表１１】

【００７５】
３．すすぎ液の調製
すすぎ液としては超純水を使用した。超純水１５００ｍＬの入ったビーカーを２つ用意した。
【００７６】
４．洗浄性評価方法
（１）テストピース１に対する洗浄性
マグネチックスターラーで、シリカ粒子を均一分散させながら５０℃に保った汚染液（Ａ）中に、直径１０ｃｍのシリコンウエハを５分間浸漬し、ウエハを汚染した。
【００７７】
汚染されたウエハを、以下の洗浄方法▲１▼、洗浄方法▲２▼又は洗浄方法▲３▼のいずれかの方法で洗浄した。
【００７８】
洗浄方法▲１▼：汚染されたウエハを、６０℃に保った洗浄液（１）中に浸漬し、３０秒間超音波（３８ＫＨｚ）を照射しながら洗浄した後、１回／２秒の割合で上下揺動しながら３分間洗浄した。
【００７９】
洗浄方法▲２▼：汚染されたウエハを、６０℃に保った洗浄液（２）中に浸漬し、３０秒間超音波（３８ＫＨｚ）を照射しながら洗浄した後、１回／２秒の割合で上下揺動しながら３分間洗浄した。
【００８０】
洗浄方法▲３▼：汚染されたウエハを、３０℃に保った洗浄液（３）中に浸漬し、３０秒間超音波（３８ＫＨｚ）を照射しながら洗浄した後、１回／２秒の割合で上下揺動しながら３分間洗浄した。
【００８１】
このようにして洗浄されたウエハを６０℃に保ったすすぎ液中に浸漬し、１回／２秒の割合で上下揺動しながら３分間すすいだ。ビーカーを替えてこの操作をもう１回行った。
【００８２】
テストピース１に対する洗浄性は、次のように評価した。
【００８３】
すすぎを終えたウエハの乾燥後、ウエハ表面に残留する粒子数を顕微鏡で観察して数え、次式から相対粒子除去率（洗浄性）を求めた。
【００８４】
相対粒子除去率（％）＝〔（対照洗浄液使用時の粒子数−洗浄液使用時の粒子数）／（対照洗浄液使用時の粒子数）〕×１００
結果を表６〜表８に示す。
【００８５】
（２）テストピース２に対する洗浄性
テストピース１に対する洗浄性試験と同様の方法で、シリコンウエハを汚染液（Ｂ）で汚染し、汚染されたウエハの洗浄、洗浄されたウエハのすすぎを行った。テストピース２に対する洗浄性の評価は、テストピース１に対する洗浄性の評価と同様にして行った。
【００８６】
また、すすぎを終えたウエハの乾燥後、ウエハ表面に残留する有機物を溶剤で抽出し、堀場ＯＣＭＡ油分分析計でその有機物量を測定し、次式から相対油分除去率（洗浄性）を求めた。
【００８７】
相対油分除去率（％）＝〔（対照洗浄液使用時の有機物量−洗浄液使用時の有機物量）／（対照洗浄液使用時の有機物量）〕×１００
【００８８】
ここで「対照洗浄液」とは、洗浄方法▲１▼においては、純水とアンモニア水からなるｐＨ７．５の液体であり、洗浄方法▲２▼においては、ｐＨが１１のアンモニア水であり、洗浄方法▲３▼においては、ｐＨが２の塩酸水溶液である。
【００８９】
また、テストピース２の洗浄性試験において、洗浄液の起泡性についても次のようにして試験を行った。
【００９０】
５０ｍＬの目盛り付きシリンダーに、洗浄方法▲１▼で洗浄液として用いる洗浄剤組成物を２０ｍＬ入れ、３０℃に保温後、１０回上下に振とうし、１０秒間静置後の泡の体積を測定した。
【００９１】
結果を表９〜表１１に示す。
【００９２】
実施例１〜１９の洗浄剤組成物はいずれも、比較例１〜４の洗浄剤組成物に比べ良好な微粒子洗浄性を示した。さらに一般式（１）で示されるモノマーを用いて得られるポリカルボン酸化合物を用いた実施例３、４及び９の洗浄剤組成物は、より良好な微粒子洗浄性を示し、起泡性が極めて少なかった。さらに、一般式（２）又は（３）で示される化合物を洗浄剤組成物中に含む実施例１０、１１、１３、１４、及び１８の洗浄剤組成物は、泡立ちが少なく、かつ油性汚れの付着した微粒子に対し優れた洗浄性を示した。
【００９３】
また、非イオン界面活性剤を添加した実施例１２、１５〜１７及び１９の洗浄剤組成物は、さらに良好な微粒子洗浄性を示した。また、微粒子と油分とで汚染したウエハの微粒子除去性を調べることで、非イオン界面活性剤の併用効果がより明確に現れた。
【００９４】
エチレンオキサイドとプロピレンオキサイドとを付加した非イオン界面活性剤は低泡性である（実施例１２）。また、ｐＨが酸性でもアルカリ性でも良好な洗浄性を示した。このことから、本発明の洗浄剤組成物の組成を適宜調整することにより、洗浄時における洗浄性と発泡性の兼ね合いに応じた洗浄剤組成物を得ることができる。
【００９５】
【発明の効果】
特定のポリカルボン酸化合物を含有することを特徴とする洗浄剤組成物及びその洗浄剤組成物を使用して洗浄することにより、半導体素子の製造工程において素子表面に付着した微粒子等の異物を効率良く洗浄、除去することができ、製造された半導体素子の歩留まり及び品質等の向上に寄与する。また、洗浄剤組成物の発泡性が低いため、洗浄における操業性や排水処理性を損なわない。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cleaning composition having a low foaming property, which is effective for removing fine organic or inorganic foreign matters and oils, and is used when forming a semiconductor element on a semiconductor substrate such as a silicon wafer. The present invention relates to a cleaning method to be used.
[0002]
[Prior art]
Semiconductor elements typified by silicon semiconductors are highly integrated to meet market needs such as higher speed, higher sensitivity, or smaller size, and the minimum circuit pattern dimensions are from 10K DRAM of 1K DRAM. Miniaturization of 4-mega DRAM to 0.8 micrometer and further miniaturization of 1 giga DRAM to 0.15 micrometer are predicted. These semiconductor elements are manufactured by repeating a plurality of processes such as resist coating, exposure, development, etching, resist removal, and semiconductor formation by ion doping after smoothing and cleaning a substrate such as a silicon wafer.
[0003]
In this semiconductor device manufacturing process, if foreign matter remains on the substrate or device, lattice defects on the substrate may occur, insulation defects in the oxide film, abnormal protrusions or stacking faults in the epitaxial film, or wire breakage or fine particles Troubles such as short circuit or leakage occur between the wires, resulting in poor quality and reduced production yield. Such a tendency becomes stronger as the degree of integration of semiconductor elements increases and the circuit pattern becomes finer. Therefore, development of a new method for removing the fine foreign matter described above has been strongly desired in order to suppress the deterioration of product quality and the decrease in yield due to the miniaturization of circuit patterns.
[0004]
Various foreign matter removal methods have been proposed to cope with such situations. A typical method is a cleaning method proposed by RCA in 1970. The outline is that the wafer is first immersed in a mixed solution of aqueous ammonia and hydrogen peroxide, and then the wafer is immersed in a mixed solution of hydrochloric acid and hydrogen peroxide. An aqueous solution treatment or pure water treatment is added.
[0005]
However, this method can remove various kinds of fine particles from the surface of the wafer by a force such as etching, but the ability to prevent reattachment of the separated fine particles is weak, so that sufficient removability may not always be obtained. is there. Therefore, there is an attempt to obtain a target cleanliness by performing a cleaning process, a post-treatment or a rinsing process using a plurality of processing tanks, but sufficient cleaning properties have not always been obtained. In particular, when a composite contaminant of oily dirt and fine particles adheres, the etching performance is hindered by the oil film, and it is therefore extremely difficult to remove the composite contaminant.
[0006]
In order to solve such a problem, various methods have been proposed. For example, Japanese Patent Laid-Open No. 6-41770 discloses a method of adding a surfactant to a treatment liquid as a cleaning liquid to maintain the zeta potential of fine particles in the treatment liquid below a certain value, Japanese Patent Laid-Open No. 6-216098. Discloses a cleaning method using a chelating agent such as EDTA, and JP-A-7-62386 discloses a cleaning composition containing a tertiary ammonium salt of fluoroalkylsulfonic acid.
[0007]
[Problems to be solved by the invention]
However, even if these cleaning agents and cleaning methods are implemented, the removal of fine particles, especially when oily dirt is attached or mixed, is not sufficient, and the use of surfactants is effective during cleaning operations and wastewater treatment. A new problem that sometimes foamed and reduced workability occurred. For this reason, the problem of the increase in the cost for washing | cleaning in manufacture of a semiconductor element, the fall of a production yield, and the fall of productivity remained a big problem. Accordingly, an object of the present invention is to provide a cleaning composition which is excellent in cleaning properties of a semiconductor substrate or semiconductor element to which solid fine particles or oily dirt adheres and has less foaming. It is a further object of the present invention to provide a cleaning method that is excellent in cleaning properties of a semiconductor substrate or semiconductor element to which solid fine particles or oily dirt adheres and has less foaming.
[0008]
[Means for Solving the Problems]
Therefore, the present inventors have studied to find a cleaning composition and a cleaning method that are excellent in the removability and detergency of solid fine particles or solid fine particles to which oily dirt adheres, and that do not cause foaming in the washing or draining process. Invented a very effective cleaning composition and cleaning method.
[0009]
  That is, the gist of the present invention is as follows.
[1] A monomer component comprising at least one selected from the group consisting of acrylic acid, methacrylic acid and maleic acidAAnd the monomer componentAIs used in an amount of 20 mol% or more of the total amount of monomer components used.Furthermore, the general formula (1):
[Chemical 3]

(Wherein R ¹ Represents a hydrogen atom, a hydrocarbon group having 1 to 18 carbon atoms, or an acyl group having 1 to 18 carbon atoms. R ² Represents a hydrogen atom or a methyl group. AO represents ethylene oxide and / or propylene oxide. m shows the integer of 1-100. ) Is used as a monomer component B, and the monomer component B is used in an amount of 5 to 70 mol% of the amount of all monomer components used.A cleaning composition for a semiconductor substrate or a semiconductor element, comprising a polycarboxylic acid compound having a weight average molecular weight of 500 to 150,000,
[2] A method for cleaning a semiconductor substrate or a semiconductor element, which is cleaned using the cleaning composition according to [1].
It is about.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
The cleaning composition and cleaning method of the present invention are applied to semiconductor substrates such as silicon wafers, chemical semiconductor wafers, glass panels in liquid crystal panels, and semiconductor elements formed on such substrates.
[0011]
1. Cleaning composition
In the cleaning composition for a semiconductor substrate or semiconductor element of the present invention, at least one selected from the group consisting of acrylic acid, methacrylic acid and maleic acid is used as a monomer component (hereinafter referred to as “monomer component A”). It contains a polycarboxylic acid compound having a weight average molecular weight of 500 to 150,000, which is obtained by using 20 mol% or more of the components in the amount used of all monomer components. The cleaning composition containing the polycarboxylic acid compound is particularly excellent in the cleaning property of fine particles on the semiconductor substrate and the semiconductor element, has few bubbles during use, and is excellent in cleaning workability.
[0012]
The total amount of the monomer component A used is preferably 20 mol% or more, more preferably 50 mol% or more, based on the amount used of all monomer components, from the viewpoint of preventing deterioration of the cleaning property of fine particle stains due to a decrease in water solubility. % Or more is particularly preferable.
[0013]
As the polycarboxylic acid compound in the present invention, from the viewpoint of fine particle removability, the ratio of acrylic acid and maleic acid in all monomer components is more preferably 70 mol% or more. Among them, the case where the molar ratio of acrylic acid / maleic acid is 9/1 to 5/5 is particularly preferable.
[0014]
The weight average molecular weight of the polycarboxylic acid compound is 500 or more, and more preferably 1000 or more, from the viewpoint of obtaining sufficient fine particle removability. From the viewpoint of preventing agglomeration from appearing and reducing fine particle removability, the weight average molecular weight is 150,000 or less, more preferably 100,000 or less, and particularly preferably 50,000 or less.
[0015]
Further, from the viewpoint of improving the cleaning properties of the fine particles, the monomer component is further represented by the general formula (1):
[0016]
[Chemical 3]

[0017]
(Wherein R¹ Represents a hydrogen atom, a hydrocarbon group having 1 to 18 carbon atoms, or an acyl group having 1 to 18 carbon atoms. R² Represents a hydrogen atom or a methyl group. AO represents ethylene oxide and / or propylene oxide. m shows the integer of 1-100. ) (Referred to as “monomer component B”) is preferably used in an amount of 5 to 70 mol% of the amount of all monomer components used.
[0018]
In the general formula (1), R¹ May be linear or branched, may be saturated or unsaturated, and may or may not contain an aromatic or alicyclic ring. Also good.
[0019]
Specific examples of the hydrocarbon group having 1 to 18 carbon atoms include, for example, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, hexyl group, octyl group, 2-ethylhexyl group, and decyl group. , Isodecyl group, tridecyl group, stearyl group, oleyl group, vinyl group, benzyl group, phenylethyl group, phenyl group, methylphenyl group, ethylphenyl group, isobutylphenyl group, cyclohexyl group and the like. Specific examples of the acyl group having 1 to 18 carbon atoms include formyl group, acetyl group, propionyl group, butyryl group, isobutyryl group, hexanoyl group, octinoyl group and the like. Of these, R¹ Is preferably a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms from the viewpoint of fine particle removability.
[0020]
In the general formula (1), m represents the number of moles of AO added, and is preferably 1 or more, more preferably 2 or more, and particularly preferably 3 or more from the viewpoint of fine particle removability. Moreover, 100 or less is preferable from a viewpoint of the removal property of microparticles | fine-particles, 40 or less is more preferable, and 20 or less is especially preferable. When m is 2 or more, AO may be composed of ethylene oxide alone, may be composed of propylene oxide alone, or both may be included. When both are included, ethylene oxide and propylene oxide may be bonded in random or block form, but from the viewpoint of fine particle removal, the molar ratio of ethylene oxide and propylene oxide in the molecule Is preferably 99/1 to 50/50.
[0021]
The amount of the monomer component B used is preferably 5 mol% or more, more preferably 10 mol% or more, based on the amount of all monomer components used, from the viewpoint of fine particle removability. Further, from the viewpoint of fine particle removability, the amount of the monomer component B used is preferably 70 mol% or less, more preferably 40 mol% or less of the total monomer component usage.
[0022]
Other compounds may be used as the monomer component of the polycarboxylic acid compound. Specifically, isobornyl acrylate, methyl acrylate, ethyl acrylate, propyl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate, aminoethyl acrylate, 4-hydroxybutyl acrylate, lauryl acrylate, acrylamide, Acrylic acid derivatives such as 2-acrylamido-2-methylpropanesulfonic acid; methyl methacrylate, ethyl methacrylate, isobutyl methacrylate, 2-ethylhexyl methacrylate, aminoethyl methacrylate, 2-hydroxyethyl methacrylate, methacrylic acid 2-hydroxypropyl, methacrylamide, 2-methacrylamide 2-methylpropanesulfonic acid, propyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate, methacryl Derivatives of methacrylic acid such as dimethylaminoethyl, ethylene, propylene, butylene, octene, diisobutylene, olefins having 2 to 18 carbon atoms, decene; styrene, styrene derivatives, and the like.
[0023]
The counter ion of the polycarboxylic acid compound is not particularly limited, but a nitrogen-containing compound having a molecular weight of 300 or less is preferable. For example, monoethanolamine, diethanolamine, triethanolamine, methylethanolamine, monopropanolamine, dipropanolamine, tripropanolamine, methylpropanolamine obtained by adding ethylene oxide, propylene oxide, etc. to ammonia, alkylamine or polyalkylpolyamine, Examples include amino alcohols such as monobutanolamine and aminoethylethanolamine; quaternary ammonium salts such as tetramethylammonium hydroxide and choline.
[0024]
The amount of the polycarboxylic acid compound in the cleaning composition of the present invention is preferably 0.01% by weight or more of the cleaning composition, from the viewpoint of exhibiting features such as fine particle removability and low foamability. More preferably, it is more than wt%. Further, from the viewpoint of cleaning cost, wastewater treatment property, etc., it is preferably 15% by weight or less, and more preferably 5% by weight or less.
[0025]
Furthermore, the cleaning composition of the present invention may contain a compound represented by the general formula (2) and / or a compound represented by the general formula (3). A cleaning composition containing such a compound improves the wet penetration of the cleaning component for semiconductor substrates, semiconductor elements, etc., and the cleaning performance for oily dirt, etc., without impairing fine particle removability, low foamability, etc. Excellent oily soil removing property and fine particle removability can be obtained with respect to the contaminated fine particle soil.
[0026]
The compound represented by the general formula (2) is the following formula:
[0027]
[Formula 4]

[0028]
(Wherein R^Three Represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or an alkenyl group having 2 to 5 carbon atoms. AO represents ethylene oxide and / or propylene oxide. X represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an acyl group having 1 to 4 carbon atoms. n shows the integer of 0-2. p shows the integer of 1-8. ).
[0029]
In the general formula (2), R^Three A hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkenyl group having 2 to 3 carbon atoms is preferable from the viewpoint of detergency. R^Three In the case where is an alkyl group or an alkenyl group, when the number of carbon atoms is 6 or more, the compound represented by the general formula (2) tends to foam, such being undesirable. The part (AO) may contain ethylene oxide and propylene oxide at random, or may contain a block. From the viewpoints of solubility in water and rinsing properties, X preferably has 4 or less carbon atoms when X is an alkyl group or an acyl group. X is more preferably a hydrogen atom, an alkyl group having 1 to 2 carbon atoms, or an acyl group having 1 to 2 carbon atoms from the viewpoint of detergency. p represents the added mole number of AO, and is an integer of 1 to 8, preferably an integer of 2 to 6, from the viewpoint of detergency against oily soil.
[0030]
Specific examples of the compound represented by the general formula (2) include phenol, methylphenol, isopropylphenol, isobutylphenol, ethylphenol, vinylphenol, benzyl alcohol, methylbenzyl alcohol, ethylbenzyl alcohol, isopropylbenzyl alcohol, Examples thereof include alkylene oxide adducts obtained by adding ethylene oxide and / or propylene oxide to phenols such as phenylethyl alcohol and alcohols. Further, a compound in which such an alkylene oxide adduct is reacted with an alkylene chloride such as methylene chloride, acetic acid, or the like, and the X moiety is an alkyl group or an acyl group is also included in the compound represented by the general formula (2).
[0031]
The compound represented by the general formula (3) is the following formula:
R^Five -O- (AO) p-X (3)
(Wherein R^Five Represents an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, or an acyl group having 1 to 6 carbon atoms. AO represents ethylene oxide and / or propylene oxide. X represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an acyl group having 1 to 4 carbon atoms. p shows the integer of 1-8. ).
[0032]
In general formula (3), R is selected from the viewpoint of suppressing foamability.^Five The number of carbon atoms is preferably 6 or less. R^Five Is more preferably an alkyl group having 3 to 6 carbon atoms or an alkenyl group having 3 to 6 carbon atoms from the viewpoint of detergency. The part (AO) may contain ethylene oxide and propylene oxide at random, or may contain a block. X is preferably an alkyl group or an acyl group, and the number of carbon atoms is 4 or less from the viewpoint of solubility in water and rinsing properties. X is more preferably a hydrogen atom, an alkyl group having 1 to 2 carbon atoms, or an acyl group having 1 to 2 carbon atoms from the viewpoint of detergency. p is preferably an integer of 2 to 6.
[0033]
Specific examples of the compound represented by the general formula (3) include methanol, ethanol, isopropanol, butanol, amyl alcohol, hexanol, vinyl alcohol, 1-propenyl alcohol, 1-butenyl alcohol, and other ethylene oxide and Examples thereof include alkylene oxide adducts to which propylene oxide is added. Furthermore, the compound represented by the general formula (3) includes a compound obtained by reacting such an alkylene oxide adduct with an alkylene chloride such as methylene chloride, acetic acid or the like, and converting the X moiety to an alkyl group or an acyl group.
[0034]
Since the compound represented by the general formula (2) and the compound represented by the general formula (3) have little foaming property, foaming during use of the resulting cleaning composition can be suppressed. Therefore, the cleaning composition of the present invention is preferable because it has good workability and wastewater treatment.
[0035]
When the compound represented by the general formula (2) and / or the compound represented by the general formula (3) are used in combination with the polycarboxylic acid compound, the characteristics of each compound appear synergistically, and better detergency is obtained. Demonstrated.
[0036]
Here, the ratio of the compound represented by the general formula (2) and the compound represented by the general formula (3) is not particularly limited, but in terms of weight ratio, [compound represented by the general formula (2)] / [general formula The compound represented by (3) is preferably in the range of 8/2 to 2/8.
[0037]
Furthermore, the cleaning composition of the present invention may contain a nonionic surfactant. Such a detergent composition containing a nonionic surfactant has better permeability of a cleaning component to a semiconductor substrate or a semiconductor element, and better cleaning ability to oily dirt, resulting in fine particle removability, dispersibility, etc. Is improved.
[0038]
Examples of such nonionic surfactants include compounds included in the following groups (a), (b) or (c), and compounds represented by the general formula (4). . As the nonionic surfactant, one kind may be used alone, or two or more kinds may be mixed and used. Next, specific examples of the compounds contained in each of the groups (a), (b) and (c) will be shown.
[0039]
(A) group: a compound obtained by adding ethylene oxide and / or propylene oxide to a linear or branched saturated or unsaturated alcohol having a hydrocarbon group having 7 to 22 carbon atoms, and having 1 to 22 carbon atoms A compound in which ethylene oxide and / or propylene oxide is added to a linear or branched saturated or unsaturated amine having a hydrocarbon group, and a linear or branched chain having a hydrocarbon group having 1 to 22 carbon atoms A compound in which ethylene oxide and / or propylene oxide is added to a saturated or unsaturated fatty acid.
[0040]
Group (b): a compound in which ethylene oxide and / or propylene oxide is added to a polyhydric alcohol having 2 to 10 carbon atoms, a compound in which ethylene oxide and / or propylene oxide is added to a polyamine having 2 to 10 carbon atoms And a compound obtained by adding ethylene oxide and / or propylene oxide to a polyhydric fatty acid having 2 to 10 carbon atoms.
[0041]
Group (c): A compound in which ethylene oxide and / or propylene oxide is added to alkylphenol (wherein the alkyl group has 6 or more carbon atoms), and ethylene oxide and / or propylene oxide is added to styrenated phenol. A compound in which ethylene oxide and / or propylene oxide is added to benzylated phenol, and a compound in which ethylene oxide and / or propylene oxide is added to naphthol.
[0042]
Furthermore, the compound contained in the group (a), the group (b) and the group (c) is reacted with, for example, an alkylene chloride having 1 to 4 carbon atoms, a fatty acid having 1 to 4 carbon atoms, etc. A compound having an alkyl group or an acyl group is also included in the nonionic surfactant referred to herein.
[0043]
The cleaning composition of the present invention comprising the compound represented by the general formula (4) has excellent oily soil removability, and particularly excellent removability of fine particles to which oily soil adheres. .
[0044]
The compound represented by the general formula (4) is
R⁷ -O- (AO) r-X (4)
(Wherein R⁷ Represents an alkyl group having 8 to 18 carbon atoms, an alkenyl group having 8 to 18 carbon atoms, an acyl group having 8 to 18 carbon atoms, or an alkylphenol group having 14 to 18 carbon atoms. AO represents ethylene oxide and / or propylene oxide. X represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an acyl group having 1 to 4 carbon atoms. r represents an integer of 3 to 35. ).
[0045]
In the general formula (4), R⁷ Is preferably an alkyl group having 8 to 14 carbon atoms, an alkenyl group having 8 to 14 carbon atoms, an acyl group having 8 to 14 carbon atoms, or an alkylphenol group having 14 to 16 carbon atoms from the viewpoint of detergency. The part (AO) may contain ethylene oxide and propylene oxide at random, or may contain a block.
[0046]
X is preferably a hydrogen atom, an alkyl group having 1 to 2 carbon atoms, or an acyl group having 1 to 2 carbon atoms. r is more preferably an integer of 6 to 25 from the viewpoint of detergency. In addition, the (AO) portion having a molar ratio of ethylene oxide to propylene oxide in the range of 9/1 to 5/5 is preferable because of less foaming.
[0047]
Specific examples of the nonionic surfactant represented by the general formula (4) include 2-ethylhexanol, octanol, decanol, isodecyl alcohol, tridecyl alcohol, lauryl alcohol, myristyl alcohol, stearyl alcohol, and oleyl alcohol. , Octylphenol, nonylphenol, alcohols such as dodecylphenol, compounds obtained by adding ethylene oxide and / or propylene oxide to phenols, and the like. Further, a compound in which such an alkylene oxide adduct is reacted with an alkylene chloride such as methylene chloride, acetic acid, etc., and the X moiety is an alkyl group or an acyl group is also a nonionic surfactant represented by the general formula (4). include.
[0048]
In addition, when components such as the compound represented by the general formula (2), the compound represented by the general formula (3), and the nonionic surfactant are contained in the cleaning composition, such components in the cleaning composition The total content is not particularly limited, and the cleaning composition of the present invention can be used after appropriately diluting the object to be cleaned.
[0049]
In the cleaning composition of the present invention, the pH of the cleaning composition may be appropriately adjusted in accordance with the purpose of cleaning. From the viewpoint of more effectively removing metal impurities, the cleaning composition of the present invention is preferably acidic. Specifically, a cleaning composition having at least one selected from the group consisting of hydrochloric acid, sulfuric acid, nitric acid, hydrofluoric acid, formic acid and acetic acid, and having a pH of 0.1 to 6 is preferred. In this case, the pH of the cleaning composition is more preferably 1 to 3.
[0050]
From the viewpoint of more effectively removing fine particles, the cleaning composition of the present invention is preferably alkaline. Specifically, a detergent composition having at least one selected from the group consisting of ammonia, amino alcohol, tetramethylammonium hydroxide, choline and potassium hydroxide and having a pH in the range of 8 to 14 is preferable. . In this case, the pH of the cleaning composition is more preferably 10-13.
[0051]
As amino alcohol, for example, monoethanolamine, diethanolamine, triethanolamine, methylethanolamine, methyldiethanolamine, monopropanolamine, dipropanolamine, tripropanolamine, methylpropanolamine, methyldipropanolamine, aminoethylethanolamine, etc. Is mentioned. Such amino alcohols may be used alone or in combination of two or more.
[0052]
The cleaning composition of the present invention can be blended with a silicone-based antifoaming agent, a chelating agent such as EDTA, alcohols, glycol ethers, preservatives, antioxidants and the like as long as the characteristics of the present invention are not impaired.
[0053]
You may use the cleaning composition of this invention in any process of the manufacturing process of a semiconductor element or a semiconductor substrate. For example, a cleaning process after lapping or polishing of a silicon wafer; a cleaning process before manufacturing a semiconductor element; a semiconductor element manufacturing process, for example, after resist development, after dry etching, after wet etching, after dry ashing, after resist stripping It can be used in cleaning processes before and after the CMP process, before and after the CVD process, etc .; in a semiconductor element manufacturing process such as a TFT type liquid crystal display panel.
[0054]
The cleaning composition of the present invention can be easily prepared by mixing each of the above components.
[0055]
2. Cleaning method
The cleaning method of the present invention is a method of cleaning a semiconductor substrate or a semiconductor element using the cleaning composition of the present invention. When washing with the cleaning composition of the present invention, 1) a polycarboxylic acid compound, 2) a compound represented by the general formula (2), 3) a compound represented by the general formula (3), and 4) a non-ion The total content of the surfactant is preferably 0.001 to 20% by weight, more preferably 0.01 to 20% by weight from the viewpoint of fine particle removability, detergency, etc. It is more preferable to perform the cleaning at 0.05 to 10% by weight, and it is particularly preferable to perform the cleaning at 0.1 to 5.0% by weight.
[0056]
The cleaning means that can be used in the present invention is not particularly limited, and includes immersion cleaning, rocking cleaning, cleaning using rotation of a spinner, paddle cleaning, air or liquid spray cleaning, and ultrasonic cleaning. Well-known means such as brush cleaning can be used. Such cleaning means may be implemented alone or in combination. In addition, the semiconductor substrate or the semiconductor element may be cleaned one by one in one cleaning operation, or a plurality of semiconductor substrates or semiconductor elements may be cleaned. The number of cleaning tanks used for cleaning may be one or more. The temperature of the cleaning composition at the time of cleaning is not particularly limited, but a range of 20 to 100 ° C. is preferable from the viewpoint of safety and operability.
[0057]
【Example】
Next, the present invention will be described in more detail based on examples and the present invention, but the present invention is not limited to such examples.
[0058]
Examples 1-19, Comparative Examples 1-4
1. Preparation of contaminated liquid
In a 2-liter beaker, silica particles (particle size 0.5-2 μm) assuming abrasive particles and silicon wafer wear particles are dispersed in 1500 mL of ultrapure water in an amount of 2% by weight, and the contamination liquid (A) is dispersed. Prepared. Next, 1.0 g of butyl oleate assuming a machine oil mist was added to the contaminated liquid (A) to prepare a contaminated liquid (B).
[0059]
2. Preparation of cleaning composition and cleaning solution
Using the compounds shown in Tables 1 and 2, cleaning compositions having the compositions shown in Tables 3 to 5 (numerical values are% by weight) were prepared.
[0060]
[Table 1]

[0061]
[Table 2]

[0062]
[Table 3]

[0063]
[Table 4]

[0064]
[Table 5]

[0065]
Next, the cleaning composition was diluted to prepare cleaning liquid (1), cleaning liquid (2) and cleaning liquid (3). Specifically, it is as follows.
[0066]
(1): After the cleaning composition was diluted with pure water, the pH was adjusted to 7.5 with aqueous ammonia or hydrochloric acid to obtain a cleaning solution. The total content (% by weight) of each component constituting the cleaning composition in the obtained cleaning liquid is as shown in Tables 6 to 11. Here, the cleaning liquid having a total content of 0% by weight is prepared by adjusting the pH to 7.5 with pure water and ammonia water without using the cleaning composition. The cleaning liquid thus prepared was used as cleaning liquid (1) in cleaning method (1).
[0067]
(2): A cleaning liquid was obtained by adding the cleaning composition to ammonia water having a pH of 11. The total content (% by weight) of each component constituting the cleaning composition in the obtained cleaning liquid is as shown in Tables 6 to 11. The cleaning liquid thus prepared was used as cleaning liquid (2) in cleaning method (2).
[0068]
(3): A cleaning composition was obtained by adding the cleaning composition to an aqueous hydrochloric acid solution having a pH of 2. The total content (% by weight) of each component constituting the cleaning composition in the obtained cleaning liquid is as shown in Tables 6 to 11. The cleaning liquid thus prepared was used as cleaning liquid (3) in cleaning method (3).
[0069]
[Table 6]

[0070]
[Table 7]

[0071]
[Table 8]

[0072]
[Table 9]

[0073]
[Table 10]

[0074]
[Table 11]

[0075]
3. Preparation of rinse solution
Ultra pure water was used as the rinsing liquid. Two beakers containing 1500 mL of ultrapure water were prepared.
[0076]
4). Detergency evaluation method
(1) Detergency for test piece 1
A silicon wafer having a diameter of 10 cm was immersed for 5 minutes in a contaminated liquid (A) maintained at 50 ° C. while uniformly dispersing silica particles with a magnetic stirrer to contaminate the wafer.
[0077]
The contaminated wafer was cleaned by any one of the following cleaning methods (1), (2) and (3).
[0078]
Cleaning method (1): A contaminated wafer is immersed in a cleaning solution (1) kept at 60 ° C. and cleaned while irradiating with ultrasonic waves (38 KHz) for 30 seconds, and then moved up and down at a rate of once every 2 seconds. Washed for 3 minutes while rocking.
[0079]
Cleaning method {circle over (2)}: The contaminated wafer is immersed in a cleaning solution (2) kept at 60 ° C. and cleaned while being irradiated with ultrasonic waves (38 KHz) for 30 seconds. Washed for 3 minutes while rocking.
[0080]
Cleaning method {circle around (3)}: The contaminated wafer is immersed in a cleaning liquid (3) kept at 30 ° C. and cleaned while being irradiated with ultrasonic waves (38 KHz) for 30 seconds, and then is moved up and down at a rate of once every 2 seconds. Washed for 3 minutes while rocking.
[0081]
The wafer thus cleaned was immersed in a rinsing liquid maintained at 60 ° C. and rinsed for 3 minutes while swinging up and down at a rate of once every 2 seconds. This operation was repeated once with the beaker changed.
[0082]
The cleanability of the test piece 1 was evaluated as follows.
[0083]
After drying the rinsed wafer, the number of particles remaining on the wafer surface was observed and counted with a microscope, and the relative particle removal rate (cleanability) was determined from the following equation.
[0084]
Relative particle removal rate (%) = [(number of particles when using control cleaning liquid−number of particles when using cleaning liquid) / (number of particles when using control cleaning liquid)] × 100
The results are shown in Tables 6-8.
[0085]
(2) Cleanability for test piece 2
The silicon wafer was contaminated with the contamination liquid (B) by the same method as the cleaning property test for the test piece 1, and the contaminated wafer was cleaned and the cleaned wafer was rinsed. Evaluation of the cleaning property for the test piece 2 was performed in the same manner as the evaluation of the cleaning property for the test piece 1.
[0086]
Also, after the rinsed wafer was dried, the organic matter remaining on the wafer surface was extracted with a solvent, the amount of the organic matter was measured with a Horiba OCMA oil analyzer, and the relative oil removal rate (cleanability) was obtained from the following equation. .
[0087]
Relative oil removal rate (%) = [(Amount of organic substance when using control cleaning liquid−Amount of organic substance when using cleaning liquid) / (Amount of organic substance when using control cleaning liquid)] × 100
[0088]
Here, the “control washing solution” is a liquid having a pH of 7.5 consisting of pure water and ammonia water in the washing method (1), and is ammonia water having a pH of 11 in the washing method (2). In method (3), an aqueous hydrochloric acid solution having a pH of 2 is used.
[0089]
Moreover, in the cleaning property test of the test piece 2, the test was performed for the foaming property of the cleaning liquid as follows.
[0090]
20 mL of the cleaning composition used as the cleaning liquid in cleaning method (1) was placed in a 50 mL graduated cylinder, kept at 30 ° C., shaken up and down 10 times, and the volume of the foam after standing for 10 seconds was measured. .
[0091]
The results are shown in Tables 9-11.
[0092]
The cleaning compositions of Examples 1 to 19 all showed better fine particle cleaning properties than the cleaning compositions of Comparative Examples 1 to 4. Furthermore, the cleaning compositions of Examples 3, 4 and 9 using the polycarboxylic acid compound obtained by using the monomer represented by the general formula (1) showed better fine particle cleaning properties and extremely high foaming properties. There were few. Further, the cleaning compositions of Examples 10, 11, 13, 14, and 18 containing the compound represented by the general formula (2) or (3) in the cleaning composition have less foaming and oily soil. Excellent detergency for the adhered fine particles.
[0093]
In addition, the cleaning compositions of Examples 12, 15 to 17, and 19 to which a nonionic surfactant was added exhibited even better fine particle cleaning properties. In addition, by examining the removability of the wafer contaminated with the fine particles and the oil, the combined effect of the nonionic surfactant appeared more clearly.
[0094]
The nonionic surfactant added with ethylene oxide and propylene oxide has low foaming properties (Example 12). In addition, good detergency was exhibited whether the pH was acidic or alkaline. From this fact, by appropriately adjusting the composition of the cleaning composition of the present invention, it is possible to obtain a cleaning composition according to the balance between cleaning properties and foamability during cleaning.
[0095]
【The invention's effect】
A cleaning composition containing a specific polycarboxylic acid compound, and cleaning using the cleaning composition makes it possible to efficiently remove foreign matters such as fine particles adhering to the device surface in the manufacturing process of a semiconductor device. It can be cleaned and removed well, and contributes to improvement in yield and quality of the manufactured semiconductor element. Moreover, since the foamability of the cleaning composition is low, the operability and wastewater treatment in cleaning are not impaired.

Claims (9)

At least one selected from the group consisting of acrylic acid, methacrylic acid and maleic acid is used as the monomer component A , and the monomer component A is used in an amount of 20 mol% or more of the total amount of the monomer components , and the general formula (1):

(Where R ¹ Represents a hydrogen atom, a hydrocarbon group having 1 to 18 carbon atoms, or an acyl group having 1 to 18 carbon atoms. R ² represents a hydrogen atom or a methyl group. AO represents ethylene oxide and / or propylene oxide. m shows the integer of 1-100. And a polycarboxylic acid compound having a weight average molecular weight of 500 to 150,000 obtained by using the monomer component B as a monomer component B and using the monomer component B in an amount of 5 to 70 mol% of the total monomer component A cleaning composition for a semiconductor substrate or a semiconductor element. The polycarboxylic acid compound according to claim 1, wherein the polycarboxylic acid compound is obtained by using the monomer component A in an amount of 30 mol% or more of the used amount of all the monomer components and the monomer component B in an amount of 10 to 70 mol% of the used amount of all monomer components. A cleaning composition for a semiconductor substrate or a semiconductor element . The cleaning composition for semiconductor substrates or semiconductor elements according to claim 1 or 2, wherein the polycarboxylic acid compound is obtained by using the monomer component B in an amount of 10 to 30 mol% of the amount of all the monomer components used . General formula (2):

(In the formula, R ³ represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or an alkenyl group having 2 to 5 carbon atoms. AO represents ethylene oxide and / or propylene oxide. X represents a hydrogen atom or carbon. An alkyl group having 1 to 4 atoms or an acyl group having 1 to 4 carbon atoms, n represents an integer of 0 to 2, p represents an integer of 1 to 8, and a general formula; (3):
^{R 5 -O- (AO) p-} X (3)
(In the formula, R ⁵ represents an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, or an acyl group having 1 to 6 carbon atoms. AO represents ethylene oxide and / or propylene oxide. X represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or an acyl group having 1 to 4 carbon atoms, p represents an integer of 1 to 8, and at least selected from the group consisting of compounds represented by The cleaning composition according to any one of claims 1 to 3 , further comprising one kind. The cleaning composition according to any one of claims 1 to 4 , further comprising a nonionic surfactant. Nonionic surfactant is represented by the general formula (4):
R ⁷ —O— (AO) r—X (4)
(In the formula, R ⁷ represents an alkyl group having 8 to 18 carbon atoms, an alkenyl group having 8 to 18 carbon atoms, an acyl group having 8 to 18 carbon atoms, or an alkylphenol group having 14 to 18 carbon atoms. AO Represents ethylene oxide and / or propylene oxide, X represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an acyl group having 1 to 4 carbon atoms, and r represents an integer of 3 to 35). The cleaning composition according to claim 5 , which is a compound shown. The cleaning composition according to any one of claims 1 to 6 , further comprising at least one selected from the group consisting of hydrochloric acid, sulfuric acid, nitric acid, hydrofluoric acid, formic acid and acetic acid, and having a pH of 0.1 to 6 . . The cleaning agent according to any one of claims 1 to 6 , further comprising at least one selected from the group consisting of ammonia, amino alcohol, tetramethylammonium hydroxide, choline and potassium hydroxide, and having a pH of 8 to 14. Composition. The method for cleaning a semiconductor substrate or a semiconductor device is washed with claim 1-8 detergent composition according to any one of.