JP4053755B2 - CMP slurry and method for manufacturing semiconductor device - Google Patents

Description

【００５８】
この化学式に示される光重合反応により、感光性樹脂粒子３は、その接着力が高まる。すなわち、感光性樹脂粒子３は、紫外光ｈνが照射されることにより、いわゆる光接着効果が発現する。これにより、感光性樹脂粒子３、ひいてはこの感光性樹脂粒子３およびアルミナ粒子２により形成された凝集体５は、研磨パッド１６の研磨面１６ａに強力に接着される。このように、凝集体５を研磨面１６ａに強力に接着させることにより、いわゆる固定砥粒方式（固定砥粒パッド）に近い研磨環境を実現できる。
【００５９】
このような研磨環境の下においては、研磨粒子であるアルミナ粒子２は、図２に示すように、複数個集まった状態で感光性樹脂粒子３を介して研磨パッド１６に強力に保持されている。これにより、個々のアルミナ粒子２が、研磨パッド１６の研磨面１６ａの凹部２２の中に埋もれてしまい、被研磨部７の配線用Cu膜９に有効に作用しなくなるおそれを殆ど無くすことができる。したがって、配線用Cu膜９に対してアルミナ粒子２を効率よく作用させて、研磨速度を容易に向上できる。
【００６０】
また、アルミナ粒子２は、感光性樹脂粒子３を介して研磨パッド１６に強力に保持されているので、いわゆる遊離砥粒となるおそれが殆どない。これにより、ＣＭＰ処理によってSiO₂膜８の表面上から配線用Cu膜９が除去された後、埋め込み配線用溝１１内に残ったCu配線９ａの上および内部に、遊離砥粒となったアルミナ粒子２が滞留するおそれが殆どない。したがって、エロージョンおよびスクラッチなどを容易に抑制（低減）できる。
【００６１】
このように、感光性樹脂粒子３は、紫外光ｈνが照射されることにより、アルミナ粒子２の研磨効率を向上させるためのアシスト粒子としての機能を容易に高められる。ひいては、そのような感光性樹脂粒子３を含んでいるＣＭＰ用スラリー１の研磨特性を容易に向上できる。
【００６２】
以上説明したように、本発明の第１実施形態に係る半導体装置の製造方法によれば、ＣＭＰ処理を行う際にＣＭＰ用スラリー１に向けて紫外光ｈνを照射することにより、ＣＭＰ用スラリー１に含まれている感光性樹脂粒子３に光重合反応を起こさせ、その接着力を適宜、適正な状態に設定できる。ひいては、ＣＭＰ用スラリー１の研磨特性を、半導体基板６の被研磨部７の被研磨状態に応じて、適宜、適正な状態に制御して、ＣＭＰ処理を行うことができる。これにより、ＣＭＰ処理の研磨速度を向上できるとともに、Cu配線９ａ（埋め込み配線、ダマシン配線）に対する高平坦性、低エロージョン、および低欠陥密度（スクラッチ・フリー）をまとめて成立させることができる。すなわち、この第１実施形態のＣＭＰ法によれば、加工精度の高い良質な埋め込み配線（ダマシン配線）を容易に、かつ、高スループットで形成できる半導体装置の製造プロセスを容易に実現することができる。
【００６３】
したがって、本実施形態のＣＭＰ法によれば、ＣＭＰ処理が施される半導体基板６、ひいてはこの半導体基板６を利用する図示しない半導体装置の性能および品質が損なわれるおそれを殆ど無くすことができるとともに、半導体装置の歩留まりの低下、すなわち半導体装置の生産効率の低下を容易に抑制することができる。この結果、性能および品質が損なわれ難い、良質かつ長寿命な半導体装置を、歩留まりを向上させて効率よく容易に生産できるとともに、その製造コストを容易に抑制できる。すなわち、以上説明した本実施形態のＣＭＰ法によって製造される半導体装置は、その性能および品質などが高く、長寿命であるとともに、安価である。
【００６４】
（第２の実施の形態）
次に、本発明の第２実施形態に係るＣＭＰ用スラリー、および半導体装置の製造方法を、図１〜図３および図５を参照しつつ説明する。
【００６５】
この第２実施形態のＣＭＰ用スラリー、および半導体装置の製造方法は、図３に示すように、研磨粒子２と共に凝集体３１を形成する感光性樹脂粒子３２の形成材料が、前述した第１実施形態の感光性樹脂粒子３の形成材料と異なっているだけで、その他の構成、工程、作用、および効果は同様である。したがって、それらの異なっている部分について説明するとともに、前述した第１実施形態と同一の構成部分などについては同一符号を付してそれらの説明を省略する。
【００６６】
この第２実施形態の図示しないＣＭＰ用スラリーにおいては、感光性樹脂粒子には、紫外光ｈνの照射によって弾性が高まる光架橋反応を起こす感光基である図示しないアジド基を有する感光性樹脂粒子３２を用いる。研磨粒子２には、前述した第１実施形態と同様にアルミナ粒子２を用いる。アルミナ粒子２および感光性樹脂粒子３２は、図３（ａ）に示すように、前述した第１実施形態の凝集体５が形成されるのと同様のメカニズムにより、図示しないスラリー溶媒中において凝集体３１を形成している。
【００６７】
この第２実施形態のＣＭＰ用スラリーおよび半導体装置の製造方法は、以上説明した点以外は、第１実施形態のＣＭＰ用スラリーおよび半導体装置の製造方法と同じであり、本発明が解決しようとする課題を解決できるのはもちろんである。その上で、紫外光ｈνの照射によって、弾性（粘性）が高まるように光架橋反応を起こすアジド基を感光基として有している感光性樹脂粒子３２を含んでいる本実施形態のＣＭＰ用スラリー、およびこのＣＭＰ用スラリーを用いて行う本実施形態の半導体装置の製造方法は、以下の点で優れている。
【００６８】
この第２実施形態の凝集体３１を形成している感光性樹脂粒子３２は、そのままでは弾性（粘性）が低いために、従来の技術において説明したように、いわゆるＣＭＰストレスに対して脆く、形状劣化し易い。したがって、例えば高荷重印加時においては、物理的（機械的）に崩壊し易く、アルミナ粒子２に対する研磨アシスト機能を十分に果たすことが困難になるおそれがある。ひいては、この感光性樹脂粒子３２を含んでいる第２実施形態のＣＭＰ用スラリーを用いてＣＭＰ処理を行う際に、実用的な高い研磨速度を得られなくなるおそれがある。また、感光性樹脂粒子３２の弾性によるクッション効果を得難いため、エロージョンやスクラッチなどが発生し易い。このように、たとえ本発明の第２実施形態に係るＣＭＰ用スラリーを用いても、従来技術において説明したような一般的なＣＭＰ法を行う限り、実用的に十分に高い研磨速度を得ることは困難であるとともに、エロージョンやスクラッチなどに対するマージンも小さい。
【００６９】
そこで、本発明の第２実施形態に係るＣＭＰ用スラリーを用いて行う第２実施形態の半導体装置の製造方法、すなわちＣＭＰ法においては、前述した第１実施形態と同様に、半導体基板６の被研磨部７にＣＭＰ処理が施されている間、図示しない紫外線ランプによって被研磨部７上のＣＭＰ用スラリー１に向けて紫外光ｈνを照射する。ＣＭＰ用スラリー１に含まれている感光性樹脂粒子３２は、前述したように、紫外光ｈνの照射によって弾性（粘性）が高まるように光架橋反応を起こす感光基であるアジド基を有している。したがって、感光性樹脂粒子３２は、紫外光ｈνが照射されることによって光架橋反応を起こし、その弾性（粘性）が上昇するので、ＣＭＰストレスに対する耐性が向上する。
【００７０】
具体的に説明すると、感光性樹脂粒子３２が有しているアジド基は、紫外光ｈνを照射されることにより、次に示す化学式で表される反応性に富むナイトレンを効率よく生成する。
【００７１】
【化２】

【００７２】
このナイトレンが水素引き抜き反応、二重結合への付加、および次の化学式に示すようなカップリング反応を引き起こし、感光性樹脂粒子３２（ポリマー）同士の間に架橋反応が起こる。
【００７３】
【化３】

【００７４】
感光性樹脂粒子３２同士が架橋することにより、それら全体の弾性（粘性）が高まる。その結果、図３（ｂ）に示すように、高荷重印加時においても、感光性樹脂粒子３２、ひいては凝集体３１は柔軟に弾性変形できるので、物理的に崩壊し難い。すなわち、紫外光ｈνを照射されている状態の凝集体３１はＣＭＰストレスに対して強く、形状劣化し難い。したがって、アルミナ粒子２に対する研磨アシスト機能を十分に果たすことができるとともに、感光性樹脂粒子３２自体の弾性によるクッション効果を十分に発揮できる。
【００７５】
以上説明したように、この第２実施形態に係るＣＭＰ用スラリー、およびこのＣＭＰ用スラリーを用いて行うＣＭＰ法によれば、ＣＭＰ処理を行う際に、ＣＭＰ用スラリーに向けて紫外光ｈνを照射することにより、感光性樹脂粒子３２、ひいては凝集体３１の弾性（粘性）を高めて、それらのＣＭＰストレスによる形状劣化耐性を大幅に改善できる。ＣＭＰストレスに対する耐性が大幅に向上された感光性樹脂粒子３２および凝集体３１を含んでいるＣＭＰ用スラリーは、その研磨特性が大幅に向上する。すなわち、ＣＭＰ処理の研磨速度をより向上できるとともに、より高い平坦性、より低いエロージョン発生率、そしてより低い欠陥密度（さらなるスクラッチ・フリー）をまとめて成立させることができる。したがって、この第２実施形態のＣＭＰ用スラリーおよびＣＭＰ法によれば、半導体基板６の被研磨部７により適正な状態で研磨処理を施すことができる。
【００７６】
また、本実施形態のＣＭＰ法は、前述した第１実施形態のＣＭＰ法を行う際に用いた、図５（ａ）に示すＣＭＰ装置１３を用いることにより容易に行うことができる。
【００７７】
（参考例）
次に、本発明の参考例に係るＣＭＰ用スラリー、半導体装置の製造方法、および半導体装置の洗浄方法を、図４ならびに図５（ａ）および（ｂ）を参照しつつ説明する。
【００７８】
この参考例のＣＭＰ用スラリーは、図４に示すように、図示しない研磨粒子と共に凝集体４１を形成する感光性樹脂粒子４２の形成材料が、前述した第１実施形態の感光性樹脂粒子３の形成材料と異なっているだけで、その他の構成は同様である。また、この参考例の半導体装置の製造方法は、半導体基板６にＣＭＰ処理を施した後に、本発明の参考例に係る半導体装置の洗浄方法を行う点が、前述した第１実施形態の半導体装置の製造方法と異なっているだけで、その他の工程は同様である。したがって、それらの異なっている部分について説明するとともに、前述した第１実施形態と同一の構成部分などについては同一符号を付してそれらの説明を省略する。
【００７９】
この参考例の図示しないＣＭＰ用スラリーにおいては、感光性樹脂粒子には、紫外光ｈνの照射によって光分解反応が生じる感光性樹脂粒子４２を用いる。具体的には、本実施形態の感光性樹脂粒子４２には、メタクリル樹脂の一種であるポリメチルメタクリレート（ＰＭＭＡ）粒子を用いるものとする。研磨粒子２には、前述した第１実施形態と同様にアルミナ粒子２を用いる。アルミナ粒子２およびＰＭＭＡ粒子４２は、前述した第１実施形態の凝集体５が形成されるのと同様のメカニズムにより、図示しないスラリー溶媒中において凝集体４１を形成している。
【００８０】
また、この参考例の半導体装置の製造方法は、前述した本実施形態のＣＭＰ用スラリーを用いて、被研磨基板６の被研磨部７にＣＭＰ処理を施す工程と、このＣＭＰ処理が施された後の被研磨基板６に付着しているＣＭＰ用スラリーに向けて紫外光ｈνを照射しつつ、被研磨基板６を洗浄する工程と、を含むことを前提とするものである。
【００８１】
以上簡潔に説明した本参考例の半導体装置の製造方法の特徴は、ＣＭＰ処理が済んだ半導体基板６を洗浄する際に、その被研磨部７等に付着している使用済みのＣＭＰ用スラリーに向けて紫外光ｈνを照射しつつ、半導体基板６を洗浄する点にある。つまり、本実施形態の半導体装置の製造方法は、半導体装置の洗浄方法について特徴を有するものである。以下、この参考例の半導体装置の製造方法のうち、その特徴的な点である半導体装置の洗浄方法について、一例を挙げて具体的に説明する。
【００８２】
まず、第１実施形態の半導体装置の製造方法において述べたように、半導体基板６は、図５（ａ）に示されているＣＭＰ装置１３のポリッシング部１３ａにおいて、ＣＭＰ処理が施される。ＣＭＰ処理が施された後の半導体基板６は、次に、例えばその被研磨部７に付着している使用済みのＣＭＰ用スラリーや、SiO₂膜８、配線用Cu膜９、およびCu配線９ａなどの削りかすなどからなる残留物（付着物）、あるいは様々なパーティクルおよびダストなどを落すために洗浄される。
【００８３】
具体的には、ＣＭＰ処理が施された半導体基板６は、ＣＭＰ装置１３のポリッシング部１３ａから、図５（ｂ）に示されているＣＭＰ装置１３の洗浄部１３ｂに運ばれる。半導体基板６は、洗浄部１３ｂ内に設置されている一対のブラシスポンジ２３の間に通される。この際、半導体基板６および各ブラシスポンジ２３には、洗浄部１３ｂ内に通されている複数本の洗浄用ホース２５、およびそれら各洗浄用ホース２５の先端に設けられている洗浄用ノズル２４を介して、洗浄液としての純水２６が供給される。これにより、半導体基板６は、その被研磨部７に付着している使用済みのＣＭＰ用スラリーや、あるいはSiO₂膜８、配線用Cu膜９、およびCu配線９ａなどの削りかすなどからなる残留物などを洗い落とされる。
【００８４】
また、このＣＭＰ装置１３の洗浄部１３ｂ内には、図５（ｂ）に示すように、その洗浄部筐体２７内に、一対のブラシスポンジ２３およびそれらの間に通される半導体基板６に向けて紫外光ｈνを照射可能な紫外光照射装置としての紫外線ランプ２８が設置されている。この紫外線ランプ２８は、前述したＣＭＰ装置１３のポリッシング部１３ａ内に設けられている紫外線ランプ１９と同様に、具体的には、ブラックライトあるいは水銀ランプなどが用いられる。半導体基板６には、これがＣＭＰ装置１３の洗浄部１３ｂ内において洗浄されている間、紫外線ランプ２８から紫外光ｈνが照射される。
【００８５】
この参考例のＣＭＰ用スラリー、およびこのＣＭＰ用スラリーを用いて行う本実施形態の半導体装置の製造方法は、以上説明した点以外は、第１実施形態のＣＭＰ用スラリーと同じである。その上で、紫外光ｈνの照射によって、光分解反応が生じるＰＭＭＡ粒子４２を含んでいる本実施形態のＣＭＰ用スラリー、およびこのＣＭＰ用スラリーを用いて半導体基板６にＣＭＰ処理を施した後に、ＣＭＰ用スラリーに向けて紫外光ｈνを照射しつつ半導体基板６を洗浄する工程を含む半導体装置の製造方法は、以下の点で優れている。
【００８６】
ＣＭＰ処理が終了した後の半導体基板６の被研磨部７には、使用済みのＣＭＰ用スラリーや、あるいはSiO₂膜８、配線用Cu膜９、およびCu配線９ａなどの削りかすなどが残留している。単なるSiO₂膜８、配線用Cu膜９、およびCu配線９ａなどの削りかすは、一般に行われている洗浄方法で略完全に半導体基板６の被研磨部７から洗い落として除去できる。ところが、使用済みのＣＭＰ用スラリーに含まれているＰＭＭＡ粒子４２は、被研磨部７のCu配線９ａ上などに残留し易く、一般に行われている洗浄方法では洗い落とすことが困難である。ＰＭＭＡ粒子４２は、配線用Cu膜９や、Cu配線９ａなどの金属の削りかすを含んでおり、導電性を有している。したがって、従来の技術において説明したように、配線間のショート歩留まりなどを引き起こすおそれがある。このように、たとえ本発明の参考例に係るＣＭＰ用スラリーを用いても、一般に行われている洗浄方法を行う限り、半導体基板６、およびこの半導体基板６を利用する半導体装置の性能および品質を劣化させる要因を略完全に取り除くことは困難である。
【００８７】
そこで、本発明の参考例に係る半導体装置の製造方法、すなわち半導体装置の洗浄方法においては、半導体基板６を洗浄している間、半導体基板６に向けて紫外光ｈνを照射する。ＣＭＰ用スラリーに含まれているＰＭＭＡ粒子４２は、前述したように、紫外光ｈνの照射によって光分解反応が生じる感光性を有している。したがって、ＰＭＭＡ粒子４２は、紫外光ｈνが照射されることによって光分解反応を起こし、その分散性（溶解度）が上昇する。
【００８８】
具体的には、ＰＭＭＡ粒子４２は、紫外光ｈνを照射されることにより、次に示す化学式で表されるように、次々にβ切断を繰り返して分解する。
【００８９】
【化４】

【００９０】
これにより、被研磨部７のCu配線９ａ上などに残留している、金属の削りかすなどを含んだＰＭＭＡ粒子４２（残留樹脂）は、ＣＭＰ用スラリーや、あるいは洗浄液である純水２６中に容易に溶ける。したがって、図４に示すように、ＰＭＭＡ粒子４２、あるいはアルミナ粒子２およびＰＭＭＡ粒子４２からなる凝集体４１、ひいてはそれらを含んでいるＣＭＰ用スラリーを、被研磨部７から略完全にかつ容易に洗い落として除去できる。
【００９１】
したがって、半導体基板６、およびこの半導体基板６を利用する半導体装置の性能および品質を損なうおそれが極めて低いとともに、半導体装置の生産効率をさらに向上できる。
【００９２】
以上説明した本参考例の半導体装置の製造方法の特徴的な部分である、半導体装置の洗浄方法は、次のように表現することができる。
【００９３】
ＣＭＰ用スラリーを用いて研磨される被研磨基板６を洗浄する半導体装置の洗浄方法において、ＣＭＰ用スラリーには、光（紫外光ｈν）の照射によって光分解反応が生じる感光性樹脂粒子としてのＰＭＭＡ粒子４２を含有させるとともに、被研磨基板６を洗浄する際に、被研磨基板６に付着しているＣＭＰ用スラリーに向けて光（紫外光ｈν）を照射する工程を含む。
【００９４】
なお、本発明に係るＣＭＰ用スラリーおよび半導体装置の製造方法は、前述した第１および第２の各実施形態ならびに参考例には制約されない。本発明の趣旨を逸脱しない範囲で、それらの構成や、あるいは工程などの一部を種々様々な設定に変更したり、あるいは各種設定を組み合わせて用いたりして実施することができる。
【００９５】
例えば、ＣＭＰ用スラリー中に、所定波長を有する光の照射によって光重合反応を起こす感光性樹脂粒子、所定波長を有する光の照射によって光架橋反応を起こす感光性樹脂粒子、および所定波長を有する光の照射によって光分解反応を起こす感光性樹脂粒子を適宜組み合わせて、混在させて使用しても構わない。
【００９６】
また、それら各感光性樹脂粒子の材料は、前述した第１および第２の各実施形態ならびに参考例において述べたものには限らない。例えば、所定波長を有する光の照射によって光架橋反応を起こす感光性樹脂粒子が有する感光基としては、アジド基のみならず、ジアゾ基、アジド基、シンナモイル基、シンナミリデン基、カルコン残基、イソクマリン基、２，５−ジメトキシスチルベン残基、スチリルピリジウム残基、チミン残基、α−フェニルマレメイド、アントラセン残基、および２−ピロン残基からなる群から選択される基を少なくとも一種類有していればよい。
【００９７】
あるいは、所定波長を有する光の照射によって光分解反応を起こす感光性樹脂粒子は、ＰＭＭＡ粒子には限らない。例えば、ＰＭＭＡ以外のメタクリル樹脂、およびこのメタクリル樹脂と同等の硬度を有するフェノール樹脂、ユリア樹脂、メラミン樹脂、ポリスチレン樹脂、ポリアセタール樹脂、ポリカーボネイト樹脂、およびエポキシ樹脂からなる群から選択される少なくとも一種類の樹脂から構成されていればよい。
【００９８】
また、研磨粒子の材料は、前述した第１および第２の各実施形態ならびに参考例において述べたアルミナ粒子には限らない。例えば、アルミナ、シリカ、チタニア、ベンガラ、セリア、カーボン、および二酸化マンガン、ならびにこれらの混合物からなる群から選択される少なくとも一種類の無機粒子から構成されていればよい。
【００９９】
また、ＣＭＰ用スラリー中に添加する酸化剤は、第１実施形態において述べた過酸化水素には限らない。例えば、過酸化水素、ペルオキソニ硫酸アンモニウム、リン酸、硝酸、および硝酸アンモニウムセリウムからなる群から選択される標準電極電位が−３．０〜＋３．０Ｖである酸化剤を、少なくとも１種類含有していればよい。また、ＣＭＰ用スラリー中のそれらの含有率も、重量パーセント濃度で０．１〜５．０％であればよい。
【０１００】
以上列挙した材料からなる感光性樹脂粒子、研磨粒子、あるいは酸化剤を含んでいるＣＭＰ用スラリーであれば、前述した第１および第２の各実施形態ならびに参考例と同様の効果を得ることができる。
【０１０１】
さらに、本発明に係る半導体装置の製造方法により研磨される被研磨基板の材料は、前述した配線用Cu膜には限らない。例えば、被研磨部に形成されており、本発明に係る半導体装置の製造方法により選択的に研磨される所定の金属を主成分とする膜は、Al, Cu, W, Ti, Mo, Nb, Ta, Vのうちのいずれか１種類の金属、これら各金属のうちの少なくとも１種類を主成分として含有している合金、窒化物、ホウ化物、酸化物、もしくはこれらの少なくとも２種類を組み合わせることによって形成される金属化合物の単層膜または積層膜であればよい。
【０１０２】
以上列挙した材料からなる金属によって形成されている被研磨部であれば、前述した第１および第２の各実施形態ならびに参考例と同様の効果を得ることができる。
【０１０３】
【発明の効果】
本発明に係るＣＭＰ用スラリーによれば、ＣＭＰ用スラリーに向けて光を照射することにより、感光性樹脂粒子の性質、ひいてはＣＭＰ用スラリーの研磨特性を適宜、適正な状態に設定することができる。したがって、半導体装置の性能および品質を損なうおそれを抑制でき、かつ半導体装置の生産効率を容易に向上できる。
【０１０４】
また、本発明に係る半導体装置の製造方法によれば、被研磨部の被研磨状態に応じて、ＣＭＰ用スラリーの研磨特性を適宜、適正な状態に設定して化学的機械的研磨を行うことができる。したがって、半導体装置の性能および品質を損なうおそれを抑制でき、かつ半導体装置の生産効率を容易に向上できる。
【図面の簡単な説明】
【図１】 （ａ）〜（ｃ）は、本発明の第１実施形態に係るＣＭＰ用スラリーの主要部分を簡略化して示す図。
【図２】 図１のＣＭＰ用スラリーを用いる本発明の第１実施形態に係る半導体装置の製造方法の概略を示す工程図。
【図３】 本発明の第２実施形態に係るＣＭＰ用スラリーを用いる本発明の第２実施形態に係る半導体装置の製造方法の概略を示す工程図。
【図４】 本発明の参考例に係るＣＭＰ用スラリーを用いる本発明の一つの実施形態に係る半導体装置の洗浄方法の概略を示す工程図。
【図５】 本発明に係るＣＭＰ用スラリーを用いる半導体装置の製造方法および半導体装置の洗浄方法を行う際に用いる半導体装置の製造装置であり、（ａ）は研磨部、（ｂ）は洗浄部をそれぞれ簡略化して示す斜視図。
【図６】 （ａ）および（ｂ）は、従来の技術に係るＣＭＰ用スラリーを用いた半導体装置の製造方法の概略を示す工程図。
【図７】 （ａ）および（ｂ）は、従来の技術に係るＣＭＰ用スラリーを用いた半導体装置の製造方法の概略を示す工程図。
【図８】 （ａ）および（ｂ）は、従来の技術に係るＣＭＰ用スラリーを用いた半導体装置の製造方法の概略を示す工程図。
【図９】 従来の技術に係るＣＭＰ用スラリーを用いたＣＭＰ研磨を行った後の半導体基板を示す断面図。
【符号の説明】
１…ＣＭＰ用スラリー
２…アルミナ粒子（研磨粒子）
３…アクリロイル基を有する光硬化性の感光性樹脂粒子（感光性樹脂粒子）
４…純水（ＣＭＰ用スラリーの溶媒）
５…凝集体（アルミナ研磨粒子と感光性樹脂粒子との凝集体）
６…半導体基板（被研磨基板）
７…被研磨部
８…SiO₂膜（絶縁膜、被研磨部）
９…配線用Cu膜（配線用金属膜、被研磨部）
３１…凝集体（アルミナ粒子と感光性樹脂粒子との凝集体）
３２…アミド基を有する感光性樹脂粒子（感光性樹脂粒子）
４１…凝集体（アルミナ粒子と感光性樹脂粒子との凝集体）
４２…ＰＭＭＡ（感光性樹脂粒子）
Ａ…感光性樹脂粒子の一次粒子径
Ｂ…アルミナ粒子の一次粒子径（研磨粒子の一次粒子径）
ｈν…紫外光（所定波長を有する光）[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a slurry used for a chemical mechanical polishing (CMP) method and a method for manufacturing a semiconductor device, and more particularly to formation of embedded wiring (damascene wiring) mounted on a DRAM, FeRAM, high-speed logic LSI, or the like. The present invention relates to a slurry for CMP and a method for manufacturing a semiconductor device.
[0002]
[Prior art]
In recent years, so-called back-end process steps in the semiconductor LSI manufacturing field are mounted on, for example, DRAMs, FeRAMs, and high-speed logic LSIs in order to simplify processes, improve yields, or improve the reliability of semiconductor devices. Research and development have been conducted on process technology for forming embedded wiring (damascene wiring) efficiently and with high accuracy. Among them, the chemical mechanical polishing (CMP) technique is an important technique indispensable for efficiently forming high-quality damascene wiring.
[0003]
For example, in so-called metal CMP technology, which is a CMP technology for polishing a metal portion (metal portion) such as a metal film on a semiconductor substrate, which is applied when forming a damascene wiring, a high polishing rate, high flatness, And to meet the process performance of low defect density. That is, in the metal CMP technology, a scratch-free damascene wiring forming process performance with high throughput and suppressing metal loss and oxide loss as much as possible is required.
[0004]
As means (approach) for realizing such a high-performance metal CMP technique, it is essential to improve the polishing cloth (polishing slurry) used in the CMP method and improve the polishing cloth (polishing pad). is there. In particular, the polishing performance of the slurry for CMP is an extremely important factor that is directly related to the CMP characteristics.
[0005]
There are two main problems in developing a slurry for CMP having high polishing performance. One is the enhancement of the interaction between the polishing cloth and the abrasive particles contained in the CMP slurry, and the other is the interaction between the abrasive particles and the metal film of the semiconductor substrate polished by the abrasive particles. This is an enhancement. In other words, how strongly the abrasive particles are held on the polishing cloth and how efficiently the abrasive particles held on the polishing cloth can act on the metal part is the key to improving the polishing performance of the slurry for CMP. is there.
[0006]
Currently, alumina is an example of typical abrasive particles that are commonly used. However, only an extremely slow polishing rate can be obtained with alumina alone. This is because the individual size (size) of the alumina particles is very small compared to the roughness (roughness) of the irregularities on the surface of the polishing cloth, and therefore, as shown in FIG. This is because it is buried in the recess 103 on the surface of 102 and does not effectively act on the metal film (metal film) 105 of the semiconductor substrate 104 that becomes the wiring metal.
[0007]
As a method for increasing the polishing efficiency of alumina particles, for example, in the invention disclosed in Japanese Patent Application Laid-Open No. 2000-269169, a semiconductor that increases polishing efficiency by adding resin particles that adsorb inorganic particles to a slurry solution. A method for manufacturing a device and a method for forming a buried wiring have been proposed.
[0008]
Briefly describing the present invention, alumina particles and resin particles having a particle diameter larger than that of the alumina particles are mixed (mixed) in the slurry solution. The alumina particles are charged approximately positively in the slurry solution. In contrast, the resin particles are negatively charged in the slurry solution. In this way, by mixing alumina particles and resin particles having different charges to each other in the slurry solution, a plurality of alumina particles are adsorbed (attached) around the resin particles by the Coulomb force generated between the two particles. ) To form aggregates.
[0009]
When a slurry for CMP containing such agglomerated abrasive particles is used, the polishing rate is improved. This is because, as shown in FIG. 6 (b), a substantial (effective) particle diameter increasing effect (size up) of the abrasive particles by attaching a plurality of alumina particles 101 as abrasive particles around the resin particles 106. Effect) and the fact that the resin particles 106 are elastically deformed to improve the contact state between the alumina particles 101 and the metal film (metal portion) 105. In this case, since the resin particles 106 themselves are soft and inactive, the resin particles 106 alone have almost no polishing power and function as assist particles that increase the polishing efficiency of the alumina particles 101.
[0010]
As described above, by adding the resin particles 106 to the slurry solution, the interaction between the alumina particles (polishing particles) 101 and the metal portion 105 on the semiconductor substrate 104 can be enhanced.
[0011]
[Problems to be solved by the invention]
However, the CMP slurry used in the invention of Japanese Patent Laid-Open No. 2000-269169 has the following problems.
[0012]
First, the adhesive force between the resin particles 106 and the polishing cloth 102 holding the resin particles 106 is weak. That is, the problem of enhancing the interaction between the polishing cloth 102 and the abrasive particles 101 and the resin particles 106 is not improved. As a result, during CMP polishing, for example, by the stress generated between the polishing cloth 102 and the semiconductor substrate 104, the abrasive particles 101 and the resin particles 106 that are freely moved away from the surface of the polishing cloth 102, so-called free abrasive grains 101. , 106 increase. As shown in FIG. 7A, these loose abrasive grains 101 and 106 stay in the wiring groove 107 during the CMP polishing, and advance excessive polishing of the wiring metal 105 and the like. As a result, it becomes difficult to suppress erosion such as dishing of the wiring metal 105 and thinning of the insulating film 108, and scratches 109 are easily generated in the wiring metal 105.
[0013]
Erosion, scratch 109, and the like are major factors that degrade the performance and quality of a semiconductor device (not shown). Once erosion has occurred, as shown in FIG. 7 (b), the resin particles 106 having adsorbed the alumina particles 101 also start to stay in the wiring grooves 107, so that the progress and generation of erosion are further accelerated.
[0014]
Second, since the resin particles 106 are low in elasticity (viscosity) as they are, the load from a carrier (not shown) holding the semiconductor substrate 104 or the number of rotations of a turntable (not shown) to which the polishing cloth 102 is attached. It is fragile to so-called CMP stress such as and tends to deteriorate its shape. As a result, for example, when a high load is applied, as shown in FIGS. 8A and 8B, the resin particles 106 are physically (mechanically) collapsed, and the polishing assistance for the alumina particles 101 cannot be sufficiently performed. A practically high polishing rate cannot be obtained. Further, the cushioning effect due to the inherent elasticity of the resin particles 106 cannot be obtained, and erosion, scratch 109, etc. are likely to occur. Therefore, similarly to the first problem described above, it becomes a major factor for reducing the production efficiency of the semiconductor device and a major factor for degrading the performance and quality of the semiconductor device.
[0015]
Thirdly, after the CMP polishing, the resin particles 106 are likely to remain on the wiring (wiring metal) 105 as shown in FIG. The residual resin 106a includes shavings of the metal portion (wiring metal) 105 and has conductivity. For this reason, the residual resin 106 a may cause a short yield between the wirings 105. This is a major factor that degrades the performance and quality of the semiconductor device, as in the first and second problems described above.
[0016]
The present invention has been made to solve the problems as described above, and the object of the present invention is to suppress the possibility of impairing the performance and quality of the semiconductor device and to facilitate the production efficiency of the semiconductor device. An object of the present invention is to provide a CMP slurry and a semiconductor device manufacturing method that can be improved.
[0017]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the slurry for CMP according to the present invention contains abrasive particles and photosensitive resin particles that generate at least one of a photopolymerization reaction and a photocrosslinking reaction when irradiated with light. It is characterized by.
[0018]
This slurry for CMP contains photosensitive resin particles that generate at least one of a photopolymerization reaction and a photocrosslinking reaction when irradiated with light. Therefore, by irradiating light toward the CMP slurry, the properties of the photosensitive resin particles, and hence the polishing characteristics of the CMP slurry, can be appropriately set to an appropriate state.
[0019]
In order to solve the above-described problem, a method for manufacturing a semiconductor device according to the present invention is performed when a chemical mechanical polishing process is performed on a portion to be polished of a substrate to be polished using the CMP slurry according to the present invention. , The CMP slurry Made of abrasive cloth Supplying a light onto the polishing surface and irradiating the CMP slurry on the polishing surface with light. , It is characterized by.
[0020]
In this semiconductor device manufacturing method, When the chemical mechanical polishing treatment is performed on the portion to be polished of the substrate to be polished, CMP slurry Made of abrasive cloth Light is applied to the CMP slurry on the polishing surface while being supplied onto the polishing surface. Thereby, according to the to-be-polished state of a to-be-polished part, the chemical mechanical polishing can be performed by appropriately setting the polishing characteristics of the CMP slurry to an appropriate state.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the first of the present invention. And second embodiments and reference examples A slurry for CMP and a method for manufacturing a semiconductor device will be described for each embodiment based on FIGS.
[0024]
(First embodiment)
First, a CMP slurry and a method for manufacturing a semiconductor device according to a first embodiment of the present invention will be described with reference to FIGS. 1, 2, and 5A.
[0025]
First, the CMP slurry 1 of this embodiment will be described with reference to FIGS. 1 (a) to 1 (c) and FIG.
[0026]
The CMP slurry 1 of the first embodiment is premised on containing abrasive particles 2 and photosensitive resin particles 3 that generate at least one of a photopolymerization reaction and a photocrosslinking reaction by irradiation with light. To do.
[0027]
In the present embodiment, alumina particles 2 that are a kind of inorganic particles are used as the abrasive particles. Moreover, the photocurable photosensitive resin particle 3 which has the acryloyl group which is not shown in figure which is a photosensitive group which causes the photopolymerization reaction which raises adhesive force by irradiation of the light which has a predetermined wavelength is used for the photosensitive resin particle. The acryloyl group undergoes a photopolymerization reaction that increases its adhesive strength upon irradiation with ultraviolet light or the like. The photosensitive resin particles 3 themselves have almost no polishing ability, and mainly function as assist particles for improving the polishing efficiency of the alumina particles 2.
[0028]
A plurality of alumina particles 2 and photocurable photosensitive resin particles 3 are contained in the solvent 4 of the CMP slurry 1 made of pure water, for example. Further, as shown in FIG. 1A, the plurality of alumina particles 2 and the photosensitive resin particles 3 include a plurality of alumina particles 2 on the surface of the photosensitive resin particles 3 in the solvent 4 of the CMP slurry 1. By adhering to each other, the aggregate 5 is present in a formed state. The aggregate 5 composed of the alumina particles 2 and the photosensitive resin particles 3 is formed for the following reason.
[0029]
In the present embodiment, the solvent 4 of the CMP slurry 1 is pure water. Pure water 4 has a pH of approximately 7, and is neutral. In such a neutral environment, the surfaces of the alumina particles 2 are substantially positively charged as shown in FIG. On the other hand, the surface of the photosensitive resin particle 3 is negatively charged as shown in FIG. 1B by introducing a functional group (not shown) such as (—COOH) in the neutral solvent 4. Can be made. Therefore, when both the alumina particles 2 and the photosensitive resin particles 3 having functional groups introduced therein are mixed in the solvent 4 of the CMP slurry 1 made of pure water, the alumina particles 2 are surrounded around the photosensitive resin particles 3. It will be in the state adsorbed by two or more. That is, the plurality of alumina particles 2 and the photosensitive resin particles 3 are present in a state where a plurality of aggregates 5 are formed in the solvent 4 of the CMP slurry 1 as shown in FIG. It becomes. Each aggregate 5 substantially serves as one abrasive particle.
[0030]
Moreover, as shown in FIG.1 (c), the photosensitive resin particle 3 of this embodiment uses the particle | grains in which the primary particle diameter A showing the magnitude | size for every particle | grain is the range of about 5-1000 nm. It is done. Similarly, for the alumina particles 2 of the present embodiment, as shown in FIG. 1C, particles having a primary particle diameter B representing the size of each particle in the range of about 5 to 1000 nm are preferably used. . These numerical values are set for the following reason.
[0031]
When the photosensitive resin particles 3 and the alumina particles 2 have a particle size with primary particle diameters A and B of less than about 5 nm, the Brownian motion of each of the particles 2 and 3 becomes intense. Then, the probability that the photosensitive resin particles 3 and the particles 2 and 3 of the alumina particles 2 contained in the slurry for CMP 1 (a large number) collide with each other increases, and it becomes easy to adsorb each other. As a result, the photosensitive resin particles 3 and the alumina particles 2 are unlikely to exist in a state where the individual particles 2 and 3 are dispersed (independent) in the CMP slurry 1 and are easily aggregated with each other. Since the aggregated photosensitive resin particles 3 and alumina particles 2 have a high sedimentation rate, it becomes difficult to control (maintain) the dispersibility of the particles 2 and 3. As a result, it becomes difficult to control the polishing characteristics of the CMP slurry 1 including the aggregated photosensitive resin particles 3 and alumina particles 2.
[0032]
Further, when the photosensitive resin particles 3 and the alumina particles 2 have primary particle diameters A and B that are larger than about 1000 nm, the intermolecular attractive force acting between the particles 2 and 3 increases. Then, a plurality (a large number) of photosensitive resin particles 3 and alumina particles 2 contained in the CMP slurry 1 are likely to aggregate together. As a result, as described above, the aggregated photosensitive resin particles 3 and alumina are obtained in the same manner as in the case where the primary resin particle sizes A and B of the photosensitive resin particles 3 and alumina particles 2 are less than about 5 nm. The particles 2 have a high settling velocity, and it becomes difficult to control the dispersibility of the particles 2 and 3. As a result, it becomes difficult to control the polishing characteristics of the CMP slurry 1 including the aggregated photosensitive resin particles 3 and alumina particles 2.
[0033]
In particular, when the primary particle diameters A and B of the photosensitive resin particles 3 and the alumina particles 2 are larger than about 1000 nm, the individual particle sizes are large, so that the dispersibility of each particle is remarkably lowered. To do. As a result, it becomes extremely difficult to control the polishing characteristics of the slurry 1 for CMP.
[0034]
As described above, when the photosensitive resin particles 3 and the alumina particles 2 whose primary particle diameters A and B are particle sizes outside the range of about 5 to 1000 nm are used, the polishing characteristics of the slurry 1 for CMP are used. It becomes difficult to control. As a result, there is a possibility that the polishing characteristics of the CMP slurry 1 may be deteriorated. In order to prevent such a risk, in the CMP slurry 1 of the present embodiment, the photosensitive resin particles 3 having primary particle diameters A and B each having a particle size in the range of about 5 to 1000 nm and Alumina particles 2 are used.
[0035]
In the present embodiment, the concentration of the alumina particles 2 contained in the CMP slurry 1 is preferably about 0.5 wt% to 3.0 wt% in terms of a weight percent concentration. At the same time, the concentration of the photosensitive resin particles 3 contained in the CMP slurry 1 is preferably about 0.1 to 2.0 wt% in terms of a weight percent concentration. These numerical values are set for the following reason.
[0036]
When the concentration of the alumina particles 2 and the concentration of the photosensitive resin particles 3 are higher than about 3.0 wt% and about 2.0 wt%, respectively, the number of the particles 2 and 3 contained in the CMP slurry is excessively increased. The distance between the particles 2 and 3 becomes too close. Thereby, the intermolecular attractive force which acts between each particle | grains 2 and 3 becomes large. Then, as described above, as in the case where the primary particle diameters A and B of the photosensitive resin particles 3 and the alumina particles 2 are larger than about 1000 nm, the respective particles 2 and 3 are bonded to each other. It becomes easy to aggregate each other, and it becomes difficult to control the dispersibility of these particles 2 and 3. When the dispersibility of the particles 2 and 3 is lowered, the particles 2 and 3 are adsorbed to each other, and excessively large aggregates (coarse particles) (not shown) are formed in the CMP slurry. When chemical mechanical polishing (CMP) is performed using a CMP slurry containing such coarse particles, the following problems may occur.
[0037]
Here, a semiconductor substrate 6 as a substrate to be polished, which is subjected to a CMP process in a semiconductor device manufacturing method to be described later, will be briefly described with reference to FIG.
[0038]
As shown in FIG. 2, the semiconductor substrate 6 is, for example, silicon dioxide (SiO 2) in which a buried wiring trench 11 is provided on the main surface of a base substrate (Si substrate) 10 made of silicon (Si). ₂ ) Insulating film (SiO ₂ Film) 8 is formed. This SiO ₂ On the surface of the film 8, a wiring metal film 9, which is a film mainly composed of a predetermined metal for forming a buried wiring (damascene wiring) 9a, is formed. However, in FIG. 2, only a portion (embedded wiring 9a) remaining in the embedded wiring trench 11 after the CMP process is illustrated in the wiring metal film 9. In the present embodiment, the wiring metal film 9 is a metal film mainly composed of copper (Cu), and will be referred to as a wiring Cu film 9 in the following description. At the same time, the embedded wiring 9a is referred to as a Cu wiring 9a.
[0039]
In the following description, SiO of the semiconductor substrate 6 ₂ The side on which the film 8 and the wiring Cu film 9 are formed is defined as the surface side of the semiconductor substrate 6. In this embodiment, the portion to be polished 7 of the semiconductor substrate (substrate to be polished) 6 is SiO 2 ₂ The film 8 and the wiring Cu film 9 are pointed out, and the wiring Cu film 9 is mainly subjected to CMP treatment. That is, the surface of the semiconductor substrate 6 becomes the surface to be polished.
[0040]
Chemical mechanical polishing is performed on the portion to be polished 7 of the semiconductor substrate 6 described above using the CMP slurry containing a plurality of coarse particles as described above. Then, these coarse particles cause SiO ₂ The film 8 is excessively polished and tends to cause so-called thinning, which is thinner than a predetermined thickness. SiO ₂ Not only the wiring Cu film on the surface of the film 8, but also the wiring Cu film 9 remaining in the embedded wiring groove 11, that is, the Cu wiring 9a, is excessively polished to form a beaten shape. Dishing is likely to occur. Furthermore, in addition to erosion consisting of dishing and thinning, so-called scratches that cause the Cu wiring 9a to be damaged may occur frequently.
[0041]
Or the density | concentration of the alumina particle 2 and the density | concentration of the photosensitive resin particle 3 exceed about 3.0 wt% and about 2.0 wt%, respectively, and the number of each particle | grains 2 and 3 contained in the slurry 1 for CMP becomes too many. And relatively soft SiO ₂ The polishing rate (polishing rate) of the film 8 becomes excessively high, and the wiring Cu film 9 that does not remain as the Cu wiring 9a, ie, the portion outside the embedded wiring groove 11 of the relatively hard wiring Cu film 9 is unnecessary. It may be difficult to selectively polish and remove the portion.
[0042]
On the other hand, when the concentration of the alumina particles 2 and the concentration of the photosensitive resin particles 3 are less than about 0.5 wt% and about 0.1 wt%, respectively, the number of the particles 2 and 3 contained in the CMP slurry 1 is reduced. Therefore, there is a possibility that the CMP process cannot be performed on the portion to be polished 7 at a necessary and sufficient polishing rate.
[0043]
As described above, the weight percent concentrations of the alumina particles 2 and the photosensitive resin particles 3 contained in the CMP slurry 1 are about 0.5 wt-3.0 wt% and about 0.1-2.0 wt%, respectively. If it deviates from the range, there is a possibility that the polished portion 7 of the semiconductor substrate 6 cannot be efficiently polished in an appropriate state using the CMP slurry 1. That is, it becomes difficult to control the polishing characteristics of the CMP slurry 1 and the polishing characteristics of the CMP slurry 1 may be deteriorated. As a result, there is a risk that the performance and quality of the semiconductor substrate 6 subjected to the CMP process using the CMP slurry 1 and, consequently, a semiconductor device (not shown) using the semiconductor substrate 6 may be impaired, and the yield of the semiconductor device is lowered. There is also a risk that the production efficiency of the semiconductor device is lowered.
[0044]
In addition, a predetermined oxidizing agent 12 is added to the CMP slurry 1 of the present embodiment in order to improve the polishing rate and obtain a sufficiently high polishing rate in effect. This is because, for example, a brittle oxide film (not shown) is formed on the surface of the wiring Cu film 9 by adding the oxidant 12 to the CMP slurry 1, and the metal polishing ability (metal removal ability) by the alumina particles 2 is further improved. By doing. Desirably, in the CMP slurry 1 of this embodiment, hydrogen peroxide 12 having a standard electrode potential (hydrogen electrode potential) in the range of −3.0 to +3.0 V is used as the oxidant 12. Moreover, the content rate of the hydrogen peroxide 12 in the slurry 1 for CMP is set in the range of about 0.1 to 5.0% by weight percent concentration.
[0045]
Thus, by adding the hydrogen peroxide 12 whose standard electrode potential and content rate are set in the above ranges to the CMP slurry 1, a chemical assist effect that enhances the oxidizing power of the CMP slurry 1, and thus The polishing characteristics of the CMP slurry 1 can be easily improved. At the same time, the agglomerated state of the alumina particles 2 and the photosensitive resin particles 3, the agglomerated state of the agglomerates 5, and further for CMP so that the polished portion 7 of the semiconductor substrate 6 is subjected to CMP processing in an appropriate state. The polishing characteristics of the slurry 1 can be easily controlled to an appropriate state. In addition, if the standard electrode potential and the content rate of hydrogen peroxide 12 are within the above-described ranges, appropriate values are appropriately set according to the material for forming the polished portion 7 to be subjected to the CMP process, for example, the type of metal. You can set it.
[0046]
As described above, according to the CMP slurry 1 of this embodiment including the alumina particles 2 and the photosensitive resin particles 3, the aggregates 5 are formed by the alumina particles 2 and the photosensitive resin particles 3. The substantial polishing ability (polishing characteristics) of the alumina particles 2 that are abrasive particles is dramatically improved. In other words, the polishing rate (polishing rate) of the CMP slurry 1 of this embodiment is greatly improved as compared with the case where the abrasive particles contained therein are composed of individual alumina particles 2 alone. Moreover, since the CMP slurry 1 of this embodiment can easily control the adhesive force of the photosensitive resin particles 3 having an acryloyl group by irradiation or non-irradiation such as ultraviolet light, the polishing characteristics can be easily controlled.
[0047]
Therefore, by using this CMP slurry 1, the polishing portion 7 of the semiconductor substrate 6 can be efficiently set in an appropriate state while finely setting the polishing characteristics of the CMP slurry 1 according to the state of polishing. Can be polished. As a result, there is almost no possibility of impairing the performance and quality of the semiconductor substrate 6 subjected to the CMP process using the CMP slurry 1 of the present embodiment, and thus the semiconductor device (not shown) using the semiconductor substrate 6. Therefore, it is possible to easily suppress a decrease in yield of the semiconductor device, that is, a decrease in production efficiency of the semiconductor device.
[0048]
Next, a method for manufacturing the semiconductor device of this embodiment will be described with reference to FIGS. 2 and 5A.
[0049]
The manufacturing method of the semiconductor device according to the first embodiment is performed when a chemical mechanical polishing process is performed on the polishing target portion 7 of the semiconductor substrate 6 using the CMP slurry 1 according to the first embodiment of the present invention described above. Further, it is premised on including a step of irradiating light having a predetermined wavelength toward the CMP slurry 1 on the polished portion 7. The CMP slurry 1 on the portion to be polished 7 is more precisely the CMP slurry 1 in contact with the portion to be polished 7.
[0050]
In the present embodiment, the light having a predetermined wavelength irradiated toward the CMP slurry 1 is ultraviolet light. Further, the portion to be polished using the CMP slurry 1 is SiO 2 ₂ Of the portion 7 to be polished formed of the film 8 and the wiring Cu film 9, the wiring Cu film 9 which is mainly a metal portion thereof is used.
[0051]
The method for manufacturing the semiconductor device of the present embodiment briefly described above is specifically a chemical mechanical polishing method (CMP method). Hereinafter, the steps of the CMP method of the first embodiment will be described in detail with an example.
[0052]
First, as shown in FIG. 5A, a semiconductor substrate 6 that is subjected to a polishing process (CMP process) on a carrier (substrate holding part) 14 installed in a polishing unit 13a of a CMP apparatus 13 is polished. The part 7 is held in a state of facing the turntable (rotating surface plate) 15 side. On the surface of the turntable 15 facing the carrier 14, a polishing cloth (polishing pad) 16 is attached in advance so as to rotate integrally with the turntable 15. Above the polishing surface 16a, which is the surface of the polishing pad 16 facing the carrier 14, a slurry supply device 17 is set so as to supply an appropriate amount of the above-described CMP slurry 1 onto the polishing surface 16a. is set up. Prior to starting the CMP process, a predetermined amount of CMP slurry 1 is supplied in advance through the supply nozzle 17a of the slurry supply device 17 onto the polishing surface 16a.
[0053]
Further, in the polishing portion 13a of the CMP apparatus 13, as shown in FIG. 5 (a), toward the upper portion of the polishing portion casing 18 toward the CMP slurry 1 supplied on the polishing surface 16a. An ultraviolet lamp 19 is installed as an ultraviolet light irradiation device that can irradiate ultraviolet light hν. As the ultraviolet lamp 19, specifically, a black light or a mercury lamp is used.
[0054]
The CMP process is started in the state described above. First, the turntable 15 is rotationally driven by the table driving device 20 in the direction indicated by the broken line arrow in FIG. Then, the CMP slurry 1 supplied onto the polishing surface 16a spreads substantially uniformly over the polishing surface 16a. After the CMP slurry 1 spreads substantially uniformly over the entire polishing surface 16a, the semiconductor substrate 6 and the carrier 14 holding the semiconductor substrate 6 are moved by the carrier driving device 21 as indicated by white arrows in FIG. As shown, the polishing pad 16 is biased toward the polishing surface 16a side. At this time, the semiconductor substrate 6 is rotationally driven by the carrier driving device 21 through the carrier 14 in the direction indicated by the one-dot chain arrow in FIG. Further, the semiconductor substrate 6 is subjected to a predetermined load toward the polishing surface 16a of the polishing pad 16 while the surface of the polishing portion 7 (surface to be polished) is subjected to the CMP process on the portion 7 to be polished. A load of a predetermined magnitude is applied by the carrier driving device 21 through the carrier 14 so as to be pressed. As a result, as shown in FIG. 2, the CMP process (metal CMP, metal CMP) for the wiring Cu film 9, which is the main polishing portion, of the portion 7 to be polished of the semiconductor substrate 6 is started.
[0055]
However, in the state described above, the interaction between the polishing pad 16 and the agglomerates 5 is not enhanced as in the case of the CMP method using the CMP slurry according to the related art described above. That is, the adhesive force between the aggregate 5 that is substantially abrasive particles composed of the alumina particles 2 and the photosensitive resin particles 3 and the polishing surface 16 a that is the surface of the polishing pad 16 is weak (small). For this reason, it is difficult for the aggregate 5 (alumina particles 2) to efficiently act on the wiring Cu film 9 of the portion 7 to be polished and to polish in an appropriate state. As described above, even if the CMP slurry 1 according to the first embodiment of the present invention is used, as long as the general CMP method as described in the prior art is performed, the polishing rate is improved, erosion, scratches, etc. It is difficult to achieve both suppression (reduction).
[0056]
Therefore, in the CMP method according to the first embodiment of the present invention, the CMP process is performed on the polished portion 7 of the semiconductor substrate 6 toward the CMP slurry 1 on the polished portion 7 by the ultraviolet lamp 19 while the CMP process is performed. Then, the ultraviolet light hν is irradiated. As described above, the photosensitive resin particles 3 contained in the CMP slurry 1 have an acryloyl group that is a photosensitive group that causes a photopolymerization reaction so that an adhesive force is increased by irradiation with ultraviolet light hν. Therefore, the photosensitive resin particles 3 undergo a photopolymerization reaction represented by the following chemical formula when irradiated with the ultraviolet light hν.
[0057]
[Chemical 1]

[0058]
Due to the photopolymerization reaction represented by this chemical formula, the adhesive force of the photosensitive resin particles 3 is increased. That is, the photosensitive resin particles 3 exhibit a so-called photoadhesive effect when irradiated with ultraviolet light hν. As a result, the photosensitive resin particles 3 and thus the aggregates 5 formed by the photosensitive resin particles 3 and the alumina particles 2 are strongly bonded to the polishing surface 16 a of the polishing pad 16. Thus, by strongly bonding the aggregate 5 to the polishing surface 16a, a polishing environment close to a so-called fixed abrasive method (fixed abrasive pad) can be realized.
[0059]
Under such a polishing environment, the alumina particles 2 as the abrasive particles are strongly held on the polishing pad 16 via the photosensitive resin particles 3 in a state of being gathered as shown in FIG. . As a result, the individual alumina particles 2 are buried in the recesses 22 of the polishing surface 16a of the polishing pad 16, and the possibility that the alumina particles 2 do not effectively act on the wiring Cu film 9 of the portion to be polished 7 can be almost eliminated. . Therefore, the alumina particles 2 can be efficiently acted on the wiring Cu film 9 to easily improve the polishing rate.
[0060]
Further, since the alumina particles 2 are strongly held by the polishing pad 16 via the photosensitive resin particles 3, there is almost no possibility of becoming so-called free abrasive grains. As a result, the SiO treatment by the CMP process ₂ After the wiring Cu film 9 is removed from the surface of the film 8, there is almost a possibility that the alumina particles 2 which become free abrasive grains stay on and in the Cu wiring 9a remaining in the buried wiring groove 11. Absent. Therefore, erosion and scratches can be easily suppressed (reduced).
[0061]
Thus, the photosensitive resin particles 3 are easily enhanced in function as assist particles for improving the polishing efficiency of the alumina particles 2 by being irradiated with the ultraviolet light hν. As a result, the grinding | polishing characteristic of the slurry 1 for CMP containing such the photosensitive resin particle 3 can be improved easily.
[0062]
As described above, according to the method for manufacturing a semiconductor device according to the first embodiment of the present invention, the CMP slurry 1 is irradiated by irradiating the CMP slurry 1 with the ultraviolet light hν when performing the CMP process. The photopolymerization reaction is caused to occur in the photosensitive resin particles 3 contained in the resin, and the adhesive force can be appropriately set to an appropriate state. As a result, it is possible to perform the CMP process by appropriately controlling the polishing characteristics of the slurry 1 for CMP according to the state of polishing of the portion 7 to be polished of the semiconductor substrate 6. As a result, the polishing rate of the CMP process can be improved, and high flatness, low erosion, and low defect density (scratch free) with respect to the Cu wiring 9a (embedded wiring, damascene wiring) can be established. That is, according to the CMP method of the first embodiment, it is possible to easily realize a semiconductor device manufacturing process capable of forming high-quality embedded wiring (damascene wiring) with high processing accuracy with high throughput. .
[0063]
Therefore, according to the CMP method of the present embodiment, it is possible to almost eliminate the possibility that the performance and quality of the semiconductor substrate 6 to be subjected to the CMP process, and thus the semiconductor device (not shown) using the semiconductor substrate 6 may be impaired, A decrease in the yield of the semiconductor device, that is, a decrease in the production efficiency of the semiconductor device can be easily suppressed. As a result, it is possible to efficiently and easily produce a high-quality and long-life semiconductor device whose performance and quality are not impaired, and to easily suppress the manufacturing cost. That is, the semiconductor device manufactured by the CMP method of the present embodiment described above has high performance and quality, has a long life, and is inexpensive.
[0064]
(Second Embodiment)
Next, a CMP slurry and a semiconductor device manufacturing method according to a second embodiment of the present invention will be described with reference to FIGS. 1 to 3 and FIG.
[0065]
In the CMP slurry and semiconductor device manufacturing method of the second embodiment, as shown in FIG. 3, the material for forming the photosensitive resin particles 32 that form the aggregates 31 together with the abrasive particles 2 is the same as that of the first embodiment described above. Other configurations, processes, operations, and effects are the same except that the material is different from the material for forming the photosensitive resin particles 3. Therefore, the different parts will be described, and the same components as those in the first embodiment described above will be denoted by the same reference numerals and the description thereof will be omitted.
[0066]
In the CMP slurry (not shown) of the second embodiment, the photosensitive resin particles 32 have an azide group (not shown) that is a photosensitive group that undergoes a photocrosslinking reaction that increases its elasticity when irradiated with ultraviolet light hν. Is used. As the abrasive particles 2, the alumina particles 2 are used as in the first embodiment. As shown in FIG. 3A, the alumina particles 2 and the photosensitive resin particles 32 are aggregated in a slurry solvent (not shown) by the same mechanism as that of the aggregate 5 of the first embodiment described above. 31 is formed.
[0067]
The CMP slurry and semiconductor device manufacturing method of the second embodiment are the same as the CMP slurry and semiconductor device manufacturing method of the first embodiment except for the points described above, and the present invention intends to solve them. Of course, the problem can be solved. In addition, the slurry for CMP according to the present embodiment includes photosensitive resin particles 32 having an azide group that causes a photocrosslinking reaction as a photosensitive group so that elasticity (viscosity) is increased by irradiation with ultraviolet light hν. And the manufacturing method of the semiconductor device of this embodiment using this slurry for CMP is excellent in the following points.
[0068]
Since the photosensitive resin particles 32 forming the aggregates 31 of the second embodiment are low in elasticity (viscosity) as they are, as described in the prior art, they are fragile to so-called CMP stress and have a shape. It is easy to deteriorate. Therefore, for example, when a high load is applied, it tends to physically (mechanically) collapse, and it may be difficult to sufficiently perform the polishing assist function for the alumina particles 2. As a result, when CMP processing is performed using the CMP slurry of the second embodiment including the photosensitive resin particles 32, there is a possibility that a practical high polishing rate cannot be obtained. In addition, since it is difficult to obtain a cushioning effect due to the elasticity of the photosensitive resin particles 32, erosion, scratches, and the like are likely to occur. Thus, even if the CMP slurry according to the second embodiment of the present invention is used, a sufficiently high polishing rate can be obtained practically as long as the general CMP method as described in the prior art is performed. It is difficult and the margin for erosion and scratches is small.
[0069]
Therefore, in the method of manufacturing a semiconductor device according to the second embodiment, that is, using the CMP slurry according to the second embodiment of the present invention, that is, the CMP method, as in the first embodiment, the semiconductor substrate 6 is coated. While the polishing portion 7 is being subjected to the CMP process, ultraviolet light hν is irradiated toward the CMP slurry 1 on the portion 7 to be polished by an ultraviolet lamp (not shown). As described above, the photosensitive resin particles 32 contained in the CMP slurry 1 have an azide group that is a photosensitive group that causes a photocrosslinking reaction so that elasticity (viscosity) is increased by irradiation with ultraviolet light hν. Yes. Therefore, the photosensitive resin particles 32 undergo a photocrosslinking reaction when irradiated with the ultraviolet light hν, and their elasticity (viscosity) increases, so that the resistance to CMP stress is improved.
[0070]
More specifically, the azide group of the photosensitive resin particles 32 efficiently generates nitrene rich in reactivity represented by the following chemical formula when irradiated with ultraviolet light hν.
[0071]
[Chemical 2]

[0072]
This nitrene causes a hydrogen abstraction reaction, addition to a double bond, and a coupling reaction as shown in the following chemical formula, and a crosslinking reaction occurs between the photosensitive resin particles 32 (polymer).
[0073]
[Chemical 3]

[0074]
When the photosensitive resin particles 32 are cross-linked, the elasticity (viscosity) of the whole is increased. As a result, as shown in FIG. 3B, even when a high load is applied, the photosensitive resin particles 32 and thus the aggregates 31 can be elastically deformed flexibly, so that they do not physically collapse. That is, the aggregate 31 in the state irradiated with the ultraviolet light hν is strong against CMP stress and hardly deteriorates in shape. Accordingly, the polishing assist function for the alumina particles 2 can be sufficiently achieved, and the cushioning effect due to the elasticity of the photosensitive resin particles 32 can be sufficiently exhibited.
[0075]
As described above, according to the CMP slurry according to the second embodiment and the CMP method performed using the CMP slurry, the CMP slurry is irradiated with the ultraviolet light hν when performing the CMP process. By doing so, the elasticity (viscosity) of the photosensitive resin particles 32, and hence the aggregate 31 can be increased, and the shape deterioration resistance due to the CMP stress can be greatly improved. Polishing characteristics of the slurry for CMP containing the photosensitive resin particles 32 and the aggregates 31 with greatly improved resistance to CMP stress are greatly improved. That is, the polishing rate of the CMP process can be further improved, and higher flatness, lower erosion occurrence rate, and lower defect density (further scratch free) can be established together. Therefore, according to the CMP slurry and the CMP method of the second embodiment, the polishing process can be performed in an appropriate state by the portion 7 to be polished of the semiconductor substrate 6.
[0076]
Further, the CMP method of the present embodiment can be easily performed by using the CMP apparatus 13 shown in FIG. 5A used when performing the CMP method of the first embodiment described above.
[0077]
( Reference example )
Next, the present invention Reference example CMP slurry , Manufacturing method of semiconductor device ,and A semiconductor device cleaning method will be described with reference to FIGS. 4 and 5A and 5B.
[0078]
this Reference example As shown in FIG. 4, the slurry for CMP of the photosensitive resin particle 42 forming the aggregate 41 together with abrasive particles (not shown) is the same as the photosensitive resin particle 3 forming material of the first embodiment described above. The only difference is the rest of the configuration. Also this Reference example The semiconductor device manufacturing method according to the present invention is performed after the semiconductor substrate 6 is subjected to the CMP process. Reference example The semiconductor device cleaning method is different from the semiconductor device manufacturing method of the first embodiment described above, and the other steps are the same. Therefore, the different parts will be described, and the same components as those in the first embodiment described above will be denoted by the same reference numerals and the description thereof will be omitted.
[0079]
this Reference example In the CMP slurry (not shown), photosensitive resin particles 42 that undergo a photodecomposition reaction upon irradiation with ultraviolet light hν are used as photosensitive resin particles. Specifically, polymethyl methacrylate (PMMA) particles, which are a kind of methacrylic resin, are used for the photosensitive resin particles 42 of the present embodiment. As the abrasive particles 2, the alumina particles 2 are used as in the first embodiment. The alumina particles 2 and the PMMA particles 42 form aggregates 41 in a slurry solvent (not shown) by the same mechanism as that of the aggregates 5 of the first embodiment described above.
[0080]
Also this Reference example The method for manufacturing a semiconductor device includes a step of performing a CMP process on the portion to be polished 7 of the substrate to be polished 6 using the CMP slurry of the present embodiment described above, and a substrate to be polished after the CMP processing is performed. And a step of cleaning the substrate to be polished 6 while irradiating the CMP slurry adhering to the substrate 6 with the ultraviolet light hν.
[0081]
The book briefly explained above Reference example The feature of this semiconductor device manufacturing method is that when cleaning the semiconductor substrate 6 after the CMP process, the used CMP slurry adhering to the polished portion 7 is irradiated with ultraviolet light hν. However, the semiconductor substrate 6 is cleaned. That is, the method for manufacturing a semiconductor device according to the present embodiment is characterized by a method for cleaning the semiconductor device. Hereafter, this Reference example Of these semiconductor device manufacturing methods, a semiconductor device cleaning method, which is a characteristic feature of the semiconductor device manufacturing method, will be specifically described with an example.
[0082]
First, as described in the method of manufacturing the semiconductor device of the first embodiment, the semiconductor substrate 6 is subjected to the CMP process in the polishing portion 13a of the CMP apparatus 13 shown in FIG. Next, the semiconductor substrate 6 after the CMP process is used, for example, used CMP slurry adhering to the polished portion 7 or SiO 2 ₂ The film 8, the Cu film for wiring 9, and the Cu wiring 9 a are cleaned to remove residues (adhered matter) such as scraps or various particles and dust.
[0083]
Specifically, the semiconductor substrate 6 that has been subjected to the CMP process is transported from the polishing unit 13a of the CMP apparatus 13 to the cleaning unit 13b of the CMP apparatus 13 shown in FIG. The semiconductor substrate 6 is passed between a pair of brush sponges 23 installed in the cleaning unit 13b. At this time, the semiconductor substrate 6 and each brush sponge 23 are provided with a plurality of cleaning hoses 25 passed through the cleaning portion 13 b and cleaning nozzles 24 provided at the tips of the respective cleaning hoses 25. Via, pure water 26 as a cleaning liquid is supplied. As a result, the semiconductor substrate 6 can be used as a used CMP slurry adhering to the portion to be polished 7 or SiO 2. ₂ Residues such as scraps such as the film 8, the wiring Cu film 9, and the Cu wiring 9a are washed away.
[0084]
Further, in the cleaning unit 13b of the CMP apparatus 13, as shown in FIG. 5B, the pair of brush sponges 23 and the semiconductor substrate 6 passed between them are provided in the cleaning unit casing 27. An ultraviolet lamp 28 is installed as an ultraviolet light irradiation device capable of irradiating the ultraviolet light hν. As the ultraviolet lamp 28, specifically, a black light or a mercury lamp is used in the same manner as the ultraviolet lamp 19 provided in the polishing portion 13a of the CMP apparatus 13 described above. The semiconductor substrate 6 is irradiated with ultraviolet light hν from the ultraviolet lamp 28 while it is being cleaned in the cleaning section 13 b of the CMP apparatus 13.
[0085]
this Reference example The CMP slurry and the method of manufacturing the semiconductor device of this embodiment using this CMP slurry are the same as the CMP slurry of the first embodiment except for the points described above. Then, after performing CMP processing on the semiconductor substrate 6 using the CMP slurry of this embodiment containing the PMMA particles 42 that undergo photodecomposition by irradiation with ultraviolet light hν, and using this CMP slurry, The semiconductor device manufacturing method including the step of cleaning the semiconductor substrate 6 while irradiating the CMP slurry with ultraviolet light hν is excellent in the following points.
[0086]
The polished portion 7 of the semiconductor substrate 6 after the CMP process is finished has a used CMP slurry or SiO 2 ₂ The shavings of the film 8, the wiring Cu film 9, the Cu wiring 9a, etc. remain. Just SiO ₂ The shavings of the film 8, the wiring Cu film 9, the Cu wiring 9a, and the like can be removed by washing off the polished portion 7 of the semiconductor substrate 6 almost completely by a generally used cleaning method. However, the PMMA particles 42 contained in the used CMP slurry are likely to remain on the Cu wiring 9a of the portion 7 to be polished, and are difficult to wash off by a commonly used cleaning method. The PMMA particles 42 include metal scraps such as the wiring Cu film 9 and the Cu wiring 9a, and have conductivity. Therefore, as described in the prior art, there is a risk of causing a short yield between the wirings. Thus, even if the present invention Reference example Even if the CMP slurry according to the above is used, as long as a generally used cleaning method is performed, it is possible to almost completely remove factors that degrade the performance and quality of the semiconductor substrate 6 and the semiconductor device using the semiconductor substrate 6. Have difficulty.
[0087]
Therefore, the present invention Reference example In the semiconductor device manufacturing method, that is, the semiconductor device cleaning method, the semiconductor substrate 6 is irradiated with ultraviolet light hν while the semiconductor substrate 6 is being cleaned. As described above, the PMMA particles 42 contained in the CMP slurry have photosensitivity that causes a photodecomposition reaction upon irradiation with ultraviolet light hν. Therefore, the PMMA particles 42 undergo a photolysis reaction when irradiated with the ultraviolet light hν, and the dispersibility (solubility) is increased.
[0088]
Specifically, the PMMA particles 42 are decomposed by repeating β cleavage one after another as represented by the following chemical formula when irradiated with ultraviolet light hν.
[0089]
[Formula 4]

[0090]
As a result, the PMMA particles 42 (residual resin) remaining on the Cu wiring 9a of the portion 7 to be polished and containing metal shavings or the like are contained in CMP slurry or pure water 26 as a cleaning liquid. It melts easily. Therefore, as shown in FIG. 4, the PMMA particles 42 or the aggregates 41 made of the alumina particles 2 and the PMMA particles 42, and thus the CMP slurry containing them, are almost completely and easily washed away from the polished portion 7. Can be removed.
[0091]
Therefore, the possibility of impairing the performance and quality of the semiconductor substrate 6 and the semiconductor device using the semiconductor substrate 6 is extremely low, and the production efficiency of the semiconductor device can be further improved.
[0092]
The book explained above Reference example The semiconductor device cleaning method, which is a characteristic part of the semiconductor device manufacturing method, can be expressed as follows.
[0093]
In the method for cleaning a semiconductor device for cleaning a substrate to be polished 6 to be polished using a CMP slurry, the CMP slurry contains PMMA as photosensitive resin particles that undergo a photodecomposition reaction upon irradiation with light (ultraviolet light hν). A step of irradiating light (ultraviolet light hν) toward the CMP slurry adhering to the substrate to be polished 6 when the substrate to be polished 6 is cleaned is included.
[0094]
The slurry for CMP according to the present invention And a method for manufacturing a semiconductor device, First mentioned above And second embodiments and reference examples There are no restrictions. In the range which does not deviate from the gist of the present invention, it is possible to carry out by changing a part of the configuration or process to various settings or using various settings in combination.
[0095]
For example, in a CMP slurry, photosensitive resin particles that undergo a photopolymerization reaction by irradiation with light having a predetermined wavelength, photosensitive resin particles that undergo a photocrosslinking reaction by irradiation with light having a predetermined wavelength, and light having a predetermined wavelength The photosensitive resin particles that undergo a photodecomposition reaction upon irradiation may be combined as appropriate and used in combination.
[0096]
Moreover, the material of each of these photosensitive resin particles is the first mentioned above. And second embodiments and reference examples It is not limited to those described in. For example, the photosensitive groups possessed by the photosensitive resin particles that undergo a photocrosslinking reaction upon irradiation with light having a predetermined wavelength include not only azide groups, but also diazo groups, azide groups, cinnamoyl groups, cinnamylidene groups, chalcone residues, isocoumarin groups. , 2,5-dimethoxystilbene residue, styrylpyridium residue, thymine residue, α-phenylmalemaid, anthracene residue, and at least one group selected from the group consisting of 2-pyrone residues It only has to be.
[0097]
Or the photosensitive resin particle which raise | generates a photolysis reaction by irradiation of the light which has a predetermined wavelength is not restricted to a PMMA particle. For example, at least one kind selected from the group consisting of methacrylic resins other than PMMA, and phenol resins, urea resins, melamine resins, polystyrene resins, polyacetal resins, polycarbonate resins, and epoxy resins having the same hardness as this methacrylic resin What is necessary is just to be comprised from resin.
[0098]
The material of the abrasive particles is the first mentioned above. And second embodiments and reference examples It is not limited to the alumina particles described in. For example, it may be composed of at least one kind of inorganic particles selected from the group consisting of alumina, silica, titania, bengara, ceria, carbon, manganese dioxide, and mixtures thereof.
[0099]
Further, the oxidizing agent added to the CMP slurry is not limited to hydrogen peroxide described in the first embodiment. For example, if it contains at least one oxidizing agent having a standard electrode potential of −3.0 to +3.0 V selected from the group consisting of hydrogen peroxide, ammonium peroxodisulfate, phosphoric acid, nitric acid, and ammonium cerium nitrate Good. Further, their content in the CMP slurry may be 0.1 to 5.0% in terms of weight percent concentration.
[0100]
The CMP slurry containing the photosensitive resin particles, abrasive particles, or oxidizing agent made of the materials listed above can be used as described above. And second embodiments and reference examples The same effect can be obtained.
[0101]
Furthermore, the material of the substrate to be polished that is polished by the method for manufacturing a semiconductor device according to the present invention is not limited to the wiring Cu film described above. For example, a film mainly composed of a predetermined metal that is formed in a portion to be polished and selectively polished by the method of manufacturing a semiconductor device according to the present invention includes Al, Cu, W, Ti, Mo, Nb, Any one of Ta and V metals, an alloy containing at least one of these metals as a main component, nitride, boride, oxide, or a combination of at least two of these It may be a single layer film or a laminated film of a metal compound formed by the above.
[0102]
If the portion to be polished is formed of a metal made of the materials listed above, the first described above. And second embodiments and reference examples The same effect can be obtained.
[0103]
【The invention's effect】
According to the CMP slurry of the present invention, by irradiating light toward the CMP slurry, the properties of the photosensitive resin particles and thus the polishing characteristics of the CMP slurry can be appropriately set to an appropriate state. . Therefore, the possibility of impairing the performance and quality of the semiconductor device can be suppressed, and the production efficiency of the semiconductor device can be easily improved.
[0104]
In addition, according to the method for manufacturing a semiconductor device according to the present invention, chemical mechanical polishing is performed by appropriately setting the polishing characteristics of the slurry for CMP to an appropriate state in accordance with the state of polishing of the portion to be polished. Can do. Therefore, the possibility of impairing the performance and quality of the semiconductor device can be suppressed, and the production efficiency of the semiconductor device can be easily improved.
[Brief description of the drawings]
FIGS. 1A to 1C are simplified views of main parts of a CMP slurry according to a first embodiment of the present invention.
FIG. 2 is a process chart showing an outline of a method for manufacturing a semiconductor device according to the first embodiment of the present invention using the CMP slurry of FIG. 1;
FIG. 3 is a process diagram showing an outline of a semiconductor device manufacturing method according to a second embodiment of the present invention using a CMP slurry according to the second embodiment of the present invention;
FIG. 4 of the present invention Reference example FIG. 4 is a process diagram showing an outline of a method for cleaning a semiconductor device according to an embodiment of the present invention using the CMP slurry according to the first embodiment.
[Figure 5] According to the present invention BRIEF DESCRIPTION OF THE DRAWINGS It is the semiconductor device manufacturing apparatus used when performing the manufacturing method of the semiconductor device which uses the slurry for CMP, and the cleaning method of a semiconductor device, (a) is a perspective view which simplifies and shows a grinding | polishing part and (b), respectively. .
FIGS. 6A and 6B are process diagrams schematically showing a method for manufacturing a semiconductor device using a CMP slurry according to the prior art. FIGS.
FIGS. 7A and 7B are process diagrams schematically showing a method of manufacturing a semiconductor device using a CMP slurry according to a conventional technique. FIGS.
FIGS. 8A and 8B are process diagrams showing an outline of a method for manufacturing a semiconductor device using a CMP slurry according to the prior art. FIGS.
FIG. 9 is a cross-sectional view showing a semiconductor substrate after performing CMP polishing using a CMP slurry according to the prior art.
[Explanation of symbols]
1 ... Slurry for CMP
2. Alumina particles (abrasive particles)
3 ... Photocurable photosensitive resin particles having an acryloyl group (photosensitive resin particles)
4. Pure water (CMP slurry solvent)
5 ... Aggregates (Agglomerates of alumina abrasive particles and photosensitive resin particles)
6 ... Semiconductor substrate (substrate to be polished)
7 ... part to be polished
8 ... SiO ₂ Film (insulating film, part to be polished)
9 ... Cu film for wiring (metal film for wiring, polished part)
31 ... Aggregate (Agglomerate of alumina particles and photosensitive resin particles)
32. Photosensitive resin particles having an amide group (photosensitive resin particles)
41. Aggregate (Agglomerate of alumina particles and photosensitive resin particles)
42 ... PMMA (photosensitive resin particles)
A: Primary particle diameter of photosensitive resin particles
B: Primary particle diameter of alumina particles (primary particle diameter of abrasive particles)
hν: ultraviolet light (light having a predetermined wavelength)

Claims (13)

Abrasive particles,
Photosensitive resin particles in which at least one of a photopolymerization reaction and a photocrosslinking reaction occurs upon irradiation with light; and
A slurry for CMP, comprising:   The slurry for CMP according to claim 1, wherein the photosensitive resin particles have an acryloyl group as a photosensitive group that undergoes a photopolymerization reaction by the light irradiation.   The slurry for CMP according to claim 1, wherein the photosensitive resin particles undergo a photocrosslinking reaction upon irradiation with the light and increase in elasticity.   The photosensitive resin particles have a diazo group, an azide group, a cinnamoyl group, a cinnamylidene group, a chalcone residue, an isocoumarin group, a 2,5-dimethoxystilbene residue, a styryl as a photosensitive group that undergoes a photocrosslinking reaction by the light irradiation. 4. The CMP according to claim 3, comprising at least one group selected from the group consisting of a pyridium residue, a thymine residue, an α-phenylmalemaid, an anthracene residue, and a 2-pyrone residue. 5. Slurry.   The slurry for CMP according to any one of claims 1 to 4, wherein the photosensitive resin particles have a primary particle diameter of 5 to 1000 nm.   The abrasive particles are made of at least one kind of inorganic particles selected from the group consisting of alumina, silica, titania, bengara, ceria, carbon, manganese dioxide, and mixtures thereof. The slurry for CMP of any one of these.   The slurry for CMP according to any one of claims 1 to 6, wherein the abrasive particles have a primary particle diameter of 5 to 1000 nm.   The slurry for CMP according to any one of claims 1 to 7, wherein the abrasive particles adhere to the surface of the photosensitive resin particles to form an aggregate.   The slurry for CMP according to any one of claims 1 to 8, wherein the light is ultraviolet light. When the CMP slurry according to any one of claims 1 to 9 is used to perform a chemical mechanical polishing process on a portion to be polished of the substrate to be polished, the CMP slurry is made of a polishing cloth. the method of manufacturing a semiconductor device according to claim, further comprising the step of irradiating light toward the CMP slurry on the polishing surface is supplied onto the polishing surface.   The method of manufacturing a semiconductor device according to claim 10, wherein the light is ultraviolet light.   12. The method of manufacturing a semiconductor device according to claim 10, wherein a film mainly composed of a metal formed in the portion to be polished is selectively polished by the chemical mechanical polishing.   The metal-based film contains any one of Al, Cu, W, Ti, Mo, Nb, Ta, and V, and at least one of these metals as a main component. 13. The semiconductor device according to claim 12, wherein the semiconductor device is a single-layer film or a laminated film of a metal compound formed by combining an alloy, nitride, boride, oxide, or a combination of at least two of them. Manufacturing method.

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