JP2004134487A - Semiconductor device and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a very reliable semiconductor device through a simple manufacturing process, which is equipped with electrodes that are less contaminated. <P>SOLUTION: The semiconductor device is equipped with protruding electrodes used for external connection, and a protective film whose main component is heat-resistant resin having a thermal decomposition temperature of 300°C or above. Its manufacturing method comprises a first step of applying a positive-type photosensitive heat-resistant resin composition or its precursor composition on a semiconductor element where the protruding electrodes have been formed, a second step of making the whole surface of the semiconductor element undergo an exposure process, a third process of keeping developing the exposed semiconductor element until the surfaces of the protruding electrodes appear, and a fourth process of making the semiconductor element undergo a curing process. By this setup, the semiconductor device which is very dependable can be obtained. <P>COPYRIGHT: (C)2004,JPO

Description

【００２０】
（式中、Ｒ^１は炭素数２〜３０の２価から６価の有機基。Ｒ^２は炭素数２〜４０の２価から６価の有機基。Ｒ^３、Ｒ^４は水素、炭素数１〜２０の１価の有機基、酸またはアルカリにより脱離する基から選ばれる少なくとも１種を含む基。Ｙ、Ｚは水酸基、エーテル基、アミノ基、アミド基、チオール基、チオエーテル基から選ばれれる少なくとも１種を含む１価の基、ａ、ｂ、ｃ、ｄは０〜４の整数であり、ａ＋ｂ＋ｃ＋ｄ＞０。ｎは１０から１００万までの整数である）。
【００２１】
本発明に使用する耐熱性樹脂またはその前駆体の製造方法は特に限定されず、公知の方法を用いることができる。
【００２２】
本発明ではバンプの形成後に樹脂組成物を全体に覆うので、樹脂組成物の耐熱性は高いことが好ましい。耐熱性が低いと、例えば、熱処理中のバンプの有機物による汚染が問題になる。
【００２３】
かかる理由から、本発明に使用する保護膜は、熱分解温度が３００℃以上の耐熱性樹脂を主成分とする必要がある。ここで、主成分とは６０モル％以上であることを言う。好ましくは、樹脂成分としては前記した耐熱性樹脂またはその前駆体組成物からなることであるが、本発明の効果を損なわない範囲で、その他の樹脂成分を添加してもかまわない。
【００２４】
有機物がバンプの表面を汚染するとバンプの電気抵抗が大きくなる。この電気抵抗は、熱処理前のものに対して熱処理後に３００％以内の上昇であることが好ましく、さらに好ましくは２００％以下である。
【００２５】
バンプの電気抵抗は、１ＫΩ以下であることが好ましく、さらに好ましくは５００Ω以下である。電気抵抗が大きいと、外部への接続が不十分になり、製品の動作に問題が生じる傾向となる。
【００２６】
電気抵抗が大きくなった場合、酸素プラズマ処理、アルゴン逆スパッタ処理、還元雰囲気での高温処理、酸、アルカリ、有機溶媒などによるウェット処理などによる電気抵抗を下げる工程を加えることは可能である。これらの処理は半導体業界では一般的なものである。
【００２７】
バンプの汚染レベルは、ＸＰＳ法（Ｘ線光電子分光法）を用い、バンプ表面の金属濃度、炭素濃度、酸素濃度などを測定することで測定可能である。バンプ表面の炭素濃度は４０原子％以下が好ましく、さらに好ましくは３０原子％以下である。
【００２８】
また、ＸＰＳ法によるバンプ表面の酸素濃度は４０原子％以下が好ましい。酸素分が多いとバンプ表面から除去されにくく、固い金属酸化物を形成するので好ましくないのである。このような点から、バンプ表面の酸素濃度は３５原子％以下がより好ましい。
【００２９】
また、フッ素や硫黄は腐食の原因となるので、合計で１０原子％以下、さらに好ましくは５原子％以下が好ましい。
【００３０】
本発明に使用する耐熱性樹脂のガラス転移温度は２４０℃以上、４００℃以下であることが好ましい。２４０℃未満では半田接合時に変形が起こり、バンプにストレスを与える恐れがあり、４００℃を越えると下地基材との接着が悪くなり信頼性に問題が生じるためである。さらに好ましい範囲は２５０℃から３８０℃であり、特に好ましくは２６０℃から３５０℃である。ここで、ガラス転移温度の測定は昇温速度１０℃／分で示差熱分析法（ＤＳＣ法）による一般的な手法で求めることができる。
【００３１】
バンプを均一に露出させるためには、耐熱性樹脂組成物またはその前駆体組成物を露光した部分の溶解速度が大きくなるポジ型の感光性であることが必要である。ポジ型の感光性であることで、低照度の全面露光後に、現像においてバンプ表面が出るまで素早く溶解し、その後現像速度が大幅に低下するために、全面にわたり均一にバンプの露出した保護膜を得ることが出来るのである。
【００３２】
ポジ型の感光性にするために感光剤を加える。感光剤としては特に限定されないが、光照射で酸が発生する感光剤が好ましく使用され、例えば、４−ナフトキノンジアジドスルホン酸、５−ナフトキノンジアジドスルホン酸、６−ナフトキノンジアジドスルホン酸のフェノール、ポリフェノール類とのエステル化合物、オニウム塩、ハロゲン含有化合物、ジアゾケトン化合物、ジアゾメタン化合物、スルホン化合物、スルホン酸エステル化合物、スルホンイミド化合物などから選ばれる１種以上を耐熱性樹脂組成物に対して０．５〜４０重量％混合することが好ましい。
【００３３】
耐熱性樹脂組成物またはその前駆体組成物を塗布後、溶媒の乾燥などのためにプリベーク工程を入れることができる。プリベークの条件としては、３０℃から２００℃の温度でホットプレートを使用する場合３０秒から２０分、オーブンを使用する場合５分〜２時間の範囲で好ましく処理することができる。
【００３４】
この後、全面を露光する。露光する波長は、感光する感度のある範囲であればいずれでもかまわないが、高圧水銀灯のｇ線（４３６ｎｍ）、ｈ線（４０５ｎｍ）、ｉ線（３６５ｎｍ）などが好ましく用いられる。これ以外に超高圧水銀灯の紫外線（２５４ｎｍ）、ＫｒＦエキシマーによる紫外線（２４８ｎｍ）、ＡｒＦエキシマーによる紫外線（１９３ｎｍ）、Ｆ_２エキシマーによる紫外線（１５７ｎｍ）、Ａｒイオンレーザー（５３２ｎｍ）、キセノンランプ（連続光）などを用いることもできる。また、このような紫外線は１つの波長だけを選択的に照射することも、複数の波長を混合して照射することもできる。
【００３５】
露光量としては特に限定されないが、低照度であることが好ましい。すなわち、現像後、バンプが表面から０．５μｍから１０μｍ程度露出することが良く、ポジ型の耐熱性樹脂組成物またはその前駆体組成物が全て溶解するより少ない露光量を全面に照射する必要があるからである。このような露光量は、目標とする保護膜の膜厚により異なってくるが、一般のパターンを形成する場合の１／１０〜１／２程度の露光量が好ましく用いられる。このように本発明ではマスクを必要としないばかりでなく、露光量も小さくできる。
【００３６】
露光後、現像する。現像に使用する現像液は特に限定されないが、例えば、テトラメチルアンモニウムヒドロキシド、モノエタノールアミン、ジエチルアミノエタノール、コリンなどの有機アルカリ水溶液、水酸化ナトリウム、水酸化カリウム、炭酸カリウム、炭酸ナトリウムなどの無機アルカリ水溶液、酢酸、安息香酸、シュウ酸などの有機酸の水溶液、塩酸、硫酸、硝酸などの無機酸の水溶液、双極性非プロトン溶媒であるＮ−メチル−２−ピロリドン、Ｎ，Ｎ−ジメチルアセトアミド、Ｎ，Ｎ−ジメチルホルムアミド、ジメチルスルホキシド、ガンマブチロラクトンなどに、メタノール、エタノール、ジアセトンアルコール、エチレングリコール、プロピレングリコールモノメチルエーテルなどのアルコール類、アセトン、メチルエチルケトン、メチルイソブチルケトンなどのケトン類、酢酸エチル、酢酸ブチル、乳酸エチル、エチレングリコールモノメチルエーテルアセテート、プロピレングリコールモノメチルエーテルアセテートなどのエステル類を混合したものなどが挙げられる。
【００３７】
現像条件は特に限定されず、バンプ表面が現れるまで現像できる条件を適宜選択することができる。
【００３８】
バンプ表面を現像で露出させた後、キュアする。ここで、キュアとは耐熱性樹脂組成物またはその前駆体組成物からなる膜を熱処理、電磁波処理、薬品処理、紫外線処理などを行い、耐薬品性のある膜に変換する工程を言う。
【００３９】
キュアとして、熱処理を行う場合、１５０℃から４５０℃の範囲でオーブンを使用する場合最高温度で５分〜２時間処理を行い、ホットプレート処理の場合最高温度で３０秒から２０分程度の処理を行うのが好ましい。　また、電磁波処理を行う場合、１ＧＨｚ〜３０ＧＨｚ程度の高周波を出力１０Ｗ〜１０ＫＷで５秒から１時間加えることが好ましい。
【００４０】
熱処理、電磁波処理を行う雰囲気は特に限定されず、例えば、空気中や窒素、アルゴン、ヘリウムなどの不活性ガス中、不活性ガスに水素ガスが混合された還元ガス雰囲気中、真空中などで行うことが出来る。このような処理の時の圧力は、０．１ｔｏｒｒ以下の高真空下から１０００気圧程度の高圧下までいずれでも行うことが出来る。
【００４１】
また、キュアとして薬品による処理を行う場合、耐熱性樹脂前駆体組成物からなる膜の場合は、耐熱性樹脂前駆体を耐熱性樹脂に変換するための触媒を該薬品として用いることが好ましい。該触媒としては、例えば、ピリジン、トリエチルアミン、ピペリジン、イミダゾール、ピラゾール、テトラゾールなどの有機塩基、ホウ素塩類、リン酸、ポリリン酸、メタンスルホン酸、トリフルオロ酢酸などの酸化合物などが好ましく用いられる。反応させる温度としては、通常、常温から４００℃程度で行う。雰囲気、圧力などは上記した熱処理と同様の条件を用いることができる。
【００４２】
薬品による処理を行う場合、より耐薬品性を向上させるために、耐熱性樹脂を架橋させる化学処理を行うことが好ましい。このような化学処理に使用する化合物としては、例えば、ジメチロール化合物、ビスマレイミド類、ジエチニルベンゼン、アクリルモノマー類、アルコキシシラン類などを挙げることができる。これらの処理も温度を常温から４００℃程度加え、雰囲気、圧力などは上記熱処理と同様の条件を用いることができる。
【００４３】
紫外線を用いて架橋させて耐薬品性を向上させることもできる。このような紫外線としては、１５０ｎｍから５００ｎｍまでの紫外線、電子線、γ線などを用いることができる。紫外線のエネルギーとしては１０ｍＪ／ｃｍ^２〜１０Ｊ／ｃｍ^２程度のエネルギーを好ましく使用することができる。紫外線照射による架橋効率を高めるために、ジメチロール化合物、ビスマレイミド類、ジエチニルベンゼン、アクリルモノマー類、アルコキシシラン類などを加えることもできるし、増感剤としてビス（４−ジメチルアミノフェニル）ケトン、ベンゾフェノン、ベンゾインメチルエーテル、オニウム塩などを添加することもできる。これらの処理も温度を常温から４００℃程度加え、雰囲気、圧力などは上記熱処理と同様の条件を用いることができる。
【００４４】
耐熱性樹脂の架橋が進行すると収縮ストレスが大きくなり、金属との接着性が低下傾向となる。これを改善し、金属との接着性を向上させるために、金属と錯体を形成する基と樹脂と反応する基の両方を有した化合物を組成物中に添加することも出来る。具体的には、例えば、金属と２００℃以上の高温処理で錯体を形成するシアノ基、アミノ基、チオール基やそれらの誘導体基および耐熱性樹脂と反応するアミノ基、カルボキシル基、エステル基、水酸基、スルホニル基などを有した化合物を耐熱性樹脂に対して０．５〜２０重量％添加する方法が好ましく用いられる。０．５％未満では効果が得にくく、２０重量％を越えると、耐薬品性、耐熱性が低下傾向となり、クラックや、バンプの汚染の原因となることがある。これらの化合物として特に好ましいものは、ジシアノアニリン、ジチオ安息香酸、シアノフェノール、アミノシアノプロパン、アミノチオフェノール、チオシアノプロパン、エチレンジアミン、エチレンジアミンジアセテート、エチレンジアミン４酢酸、シアノフェニルスルホン酸、チオフェニルカルボン酸などがある。特に、アミノシアノプロパン、アミノチオフェノール、チオシアノプロパン、エチレンジアミン、エチレンジアミンジアセテートなどが好ましい。
【００４５】
本発明の方法を用いると、露出した電極と保護膜との間に隙間が存在しない半導体装置を容易に製造することができる。
【００４６】
次に本発明の半導体装置について説明する。
【００４７】
本発明の半導体装置は、外部接続用の電極と保護膜を有する半導体装置であって、該保護膜から露出した電極と保護膜との間に隙間が存在せず、かつ、該電極表面のＸＰＳ法による酸素濃度が４０原子％以下である半導体装置である。
【００４８】
ここで、隙間が存在しないとは、窪みの存在を否定するものではない。窪みが存在する場合、その深さは好ましくは保護膜厚みの５０％以下であり、より好ましくは３０％以下である。
【００４９】
本発明の半導体装置は、半導体素子をチップに切断する時に生じる切りくずが隙間に入らず、これによる不良が発生しない、また、バンプ以外の全面を保護膜で覆うことが出来るので、バンプの衝撃保護効果が大きく、より高い信頼性のある半導体素子を提供することが出来るのである。
【００５０】
本発明の半導体装置は、例えば、上記した製造方法で容易に製造できるが、それに限定されない。
【００５１】
保護膜としては、ポジ型の感光性を有する耐熱性樹脂組成物またはその前駆体組成物をキュアして得られる保護膜であることが好ましい。
【００５２】
本発明の半導体装置において、半導体素子上に冗長回路があり、これを動作テストにより切断する必要がある場合、その部分のみ保護膜を無くすことでレーザーなどにより冗長回路のヒューズを切断することもできる。この場合は、ヒューズ部分のみ保護膜の底まで十分反応させる露光を行い、その他は少量の露光を行うことで、一度の現像処理で必要なパターンを形成することができる。同様のことをスクライブ線などの形成にも使うことが出来る。
【００５３】
このようにして保護膜を形成した後、半導体素子をチップに切ることが一般的であるが、チップに切断した素子に保護膜を上記方法で形成することも可能である。
【００５４】
半導体素子の基板への実装方法は特に限定されないが、本発明の半導体装置の場合、フリップチップ接続で接続することが一般的である。
【００５５】
本発明の半導体装置の用途は、例えば、小型液晶表示素子、薄膜が必要な液晶表示素子、ビデオカメラ、携帯電話、デジタルカメラなどに用いることができるが、これ以外にも使用可能である。
【００５６】
【実施例】
以下、実施例を挙げて本発明を詳細に説明するが、本発明はこれらによって限定されるものではない。なお、実施例中の耐熱性樹脂組成物の評価は以下の方法により行った。
【００５７】
（電極表面の酸素濃度の測定）
４インチシリコンウェハーに直径２０μｍ、高さ１０μｍの金バンプを形成した基板を用意した。ここに感光性耐熱性樹脂組成物、感光性耐熱性樹脂前駆体組成物のワニスを大日本スクリーン製造（株）製の塗布現像装置ＳＣＷ−６３６の塗布装置を用いて１２０℃で３分のプリベーク後の膜厚が１２μｍになるようにスピン塗布し、同じＳＣＷ−６３６のホットプレートを用いて１２０℃で３分間処理した。キャノン（株）製コンタクトアライナーＰＬＡ−５０１を用いて所定の条件で露光を行った。露光後、所定の現像液に所定時間浸漬して、パッドの頂上部を露出させ、その後、超純水でリンスした。
【００５８】
このようにパターンを形成したウェハーを、光洋サーモシステム（株）製のイナートオーブンＩＮＨ−２１ＣＤに入れ、酸素濃度２０ｐｐｍ以下の窒素ガス雰囲気で１４０℃で３０分処理後、３．５℃／分で昇温し、２５０℃から３５０℃の範囲で６０分処理した。
【００５９】
このパターン形成により金の露出した部分をＳＳＸ−１００（ＳＳＩ社製）を用いて、励起Ｘ線に単結晶アルミのＫα１，２線（１４８６．６ｅＶ）、Ｘ線径１ｍｍ、Ｘ線出力１０ｋＶ、２０ｍＡで検出器の角度を４５度にし、中性炭素のＣ１ｓピーク位置を２８４．６ｅＶに合わせて金上に付着している元素の分析を行った。酸素のＯ１ｓに帰属されるピークは５２５ｅｖから５３５ｅＶの範囲に現れる。
【００６０】
（熱分解温度の測定）
４インチシリコンウェハーに感光性耐熱性樹脂組成物、感光性耐熱性樹脂前駆体組成物のワニスを大日本スクリーン製造（株）製の塗布現像装置ＳＣＷ−６３６の塗布装置を用いて１２０℃で３分のプリベーク後の膜厚が８μｍになるようにスピン塗布し、同じＳＣＷ−６３６のホットプレートを用いて１２０℃で３分間処理した。このウェハーを光洋サーモシステム（株）製のイナートオーブンＩＮＨ−２１ＣＤで１７０℃で３０分、その後、昇温速度３．５℃／分で３５０℃まで上げ、３５０℃で１時間処理し、１００℃以下になるまで自然冷却した。その後、ウェハーをオーブン内より取り出した。
【００６１】
このウェハーのついたキュア膜を、４７％フッ化水素酸（和光純薬（株）製、特級）に５分間浸漬した後、水道水で洗浄し、シリコンウェハから剥離し、ヤマト科学（株）製イナートオーブンＤＴ−４２を用いて、２００℃で１時間加熱処理し、吸水した水を除去した。
【００６２】
上記、耐熱性樹脂組成物のキュア膜約１０ｍｇを丸めて白金製のセルに入れて、（株）島津製作所製の熱重量分析装置ＴＧ−５０に入れて、昇温速度１０℃／分で室温から８００℃の範囲で熱重量減少を測定し、重量減少が５％起こった点を熱分解温度とした。
【００６３】
合成例１：ナフトキノンジアジド化合物１の合成
乾燥窒素気流下、４，４７−［１−［４−［１−（４−ヒドロキシフェニル）−１−メチルエチル］フェニル］エチリデン）ビスフェノール（本州化学（株）製）２１．２ｇ（０．０５モル）と５−ナフトキノンジアジドスルホニル酸クロリド（東洋合成（株）製）３２．２ｇ（０．１２モル）を１，４−ジオキサン（林純薬（株）製）５００ｇに溶解させ、４０℃に加熱した。ここに、１，４−ジオキサン５０ｇと混合させたトリエチルアミン（和光純薬（株）製）１２．１ｇ（０．１２モル）を系内の温度が４５度以上にならないように滴下した。滴下後、４０度で２時間攪拌した。副生したトリエチルアミンの塩酸塩を濾過し、ろ液を１％塩酸３ｌに投入させた。その後、析出した沈殿をろ過で集めた。さらに、水１０ｌで洗浄を２度繰り返し、５０℃の真空乾燥機で２０時間乾燥させ、ナフトキノンジアジド化合物を得た。
【００６４】
合成例２：ナフトキノンジアジド化合物２の合成
乾燥窒素気流下、１，１，２，２−テトラ（４−ヒドロキシフェニル）エタン（本州化学（株）製）１９．９ｇ（０．０５モル）と５−ナフトキノンジアジドスルホニル酸クロリド（東洋合成（株）製）３４．９ｇ（０．１３モル）を１，４−ジオキサン（林純薬（株）製）５００ｇに溶解させ、４０℃に加熱した。ここに、１，４−ジオキサン５０ｇと混合させたトリエチルアミン（和光純薬（株）製）１３．１ｇ（０．１３モル）を系内の温度が４５度以上にならないように滴下した。滴下後４０度で２時間攪拌した。副生したトリエチルアミンの塩酸塩を濾過し、ろ液を１％塩酸３ｌに投入させた。その後、析出した沈殿をろ過で集めた。さらに、水１０ｌで洗浄を２度繰り返し、５０℃の真空乾燥機で２０時間乾燥させ、ナフトキノンジアジド化合物を得た。
【００６５】
合成例３：酸無水物１（ＴＭＤＡ）の合成
攪拌羽、温度計、窒素導入管を取り付けた、１Ｌの３つ口フラスコに２，２−ビス（３−アミノ−４−ヒドロキシフェニル）ヘキサフルオロプロパン（セントラル硝子（株）製、以下ＢＡＨＦと略する）１８．３ｇ（０．０５モル）をはかり入れ、アセトン（３００ｍＬに溶解させた。ここにグリシジルメチルエーテル（東京化成（株）製、以下ＧＭＥと略する）８０ｇ（０．９１モル）を加え、溶液の温度を５℃に冷却した。ここに無水トリメリット酸クロリド（東京化成（株）製）２１．１ｇ（０．１モル）をアセトン（特級、佐々木化学薬品（株）製）２００ｍＬに溶解させた溶液を１５分かけて、溶液の温度が１０℃を越えないように滴下した。
【００６６】
滴下後、５℃で２時間攪拌し、その後、３０分かけて２５℃にした。２５℃で３０分攪拌した後、ろ過を行い、黄色い沈殿物を回収した。集めた沈殿物をさらにアセトンで２回洗浄した。この沈殿を８０℃の真空乾燥機で２４時間乾燥させ、表記の酸無水物１（ＴＭＤＡ）を得た。
【００６７】
合成例４：ジアミン１（ＨＦＨＡ）の合成
攪拌羽、温度計、窒素導入管を取り付けた、２Ｌの３つ口フラスコにＢＡＨＦ１８．３ｇ（０．０５モル）をはかり入れ、アセトン２００ｍＬに溶解させた。ここにＧＭＥ８０ｍＬ（０．９１モル）を加えて溶液の温度を５℃に冷却した。ここに３−ニトロ安息香酸クロリド（東京化成（株）製）１８．６ｇ（０．１モル）をアセトン２００ｍＬに溶解させた溶液を１５分かけて、溶液の温度が１０℃を越えないように滴下した。
【００６８】
滴下後、５℃で２時間攪拌し、その後、３０分かけて２５℃にした。２５℃で３０分攪拌した後、ろ過を行い、沈殿物を回収した。集めた沈殿物をさらにアセトンで２回洗浄した。この沈殿を安息香酸メチルで再結晶し、１００℃の真空乾燥機で４８時間乾燥し、白色粉体３３ｇを得た。
【００６９】
白色粉体１３．４ｇをはかり取り、テトラヒドロフラン（和光純薬（株）製）１００ｍＬとメタノール（片山化学（株）製）５０ｍＬの混合溶媒を４０℃にして溶解させた。ここに５％パラジウム−炭素（和光純薬（株）製）０．２ｇを加え、飽水ヒドラジン（和光純薬（株）製）８ｇを３０分かけて徐々に滴下した。その後、溶液の温度を４０℃のまま４時間攪拌を続けた。
【００７０】
その後、ろ過によりパラジウム−炭素を除去し、水１Ｌに投入して、薄黄色の沈殿を得た。これをろ過で集め、さらに水、メタノールで洗浄し、８０℃の真空乾燥機で４８時間乾燥させ、ＨＦＨＡを得た。
【００７１】
実施例１
乾燥窒素気流下、４，４’−ジアミノジフェニルエーテル（和歌山精化（株）製）１９．０ｇ（０．０９５モル）、１，３−ビス（３−アミノプロピル）テトラメチルジシロキサン（信越化学（株）製、ＡＰＤＳ）１．２４ｇ（０．００５モル）をＮ−メチル−２−ピロリドン（三菱化学（株）製、ＮＭＰ）５０ｇに４０℃で溶解させた。ここに合成例１で合成したＴＭＤＡ７１．４ｇ（０．１モル）を一度に加えた。４０℃で２時間攪拌を続けた後、ジメチルホルムアミドジメチルアセタール（三菱レーヨン（株）製、ＤＭＡ）１１．９ｇ（０．１モル）をＮＭＰ３０ｍＬで希釈した溶液を１０分かけて滴下した。
【００７２】
滴下終了後、４０℃で２時間攪拌を続け、その後酢酸１０ｍＬを加え、過剰なＤＭＡを分解した。その後、水１Ｌに投入し白色沈殿を得た。この沈殿をろ過で集め、その後、水で２回洗浄した。洗浄後の沈殿を５０℃の真空乾燥機で７２時間乾燥させポリマー１を得た。このポリマー１を１０ｇはかり取り、合成例１で合成した感光剤２ｇ、１，１，２，２−テトラ（４−ヒドロキシフェニル）エタン１ｇをガンマブチロラクトン（三菱化学（株）製、ＧＢＬ）２０ｇに溶解させた。溶解した後、１μｍのメンブレンフィルターでろ過をした。
【００７３】
この溶液をバンプを形成したウェハーに１２０℃で３分のホットプレート処理後の膜厚が１２μｍになるように大日本スクリーン製造（株）製のＳＣＷ−６３６のコーターを用いてスピンコートした。スピンコート後、１２０℃×３分のホットプレート処理をＳＣＷ−６３６のホットプレートを用いて行った。
【００７４】
このウェハーをキャノン（株）製コンタクトアライナーＰＬＡ−５０１Ａを用いて、３６５ｎｍ、４０５ｎｍ、４３６ｎｍの紫外線が混合した状態で、３６５ｎｍの測定で３０ｍＪ／ｃｍ^２の露光を全面に均一に行った。
【００７５】
本ウェハーを２３℃の２．３８％のテトラメチルアンモニウムヒドロキシド水溶液に入れ、１分間エッチングした。その後水でリンスし、５０Ｌ／分の流量で窒素の流れた光洋サーモシステム製イナートオーブンＩＮＨ−２１ＣＤで１７０℃で３０分、その後５℃／分で昇温し、２８０℃で１時間処理することでウェハー上に耐熱性樹脂であるポリイミド膜を得た。このようにして作成したバンプ表面の炭素濃度は３０原子％、酸素濃度は３１原子％であった。このものの熱分解温度は５３０℃であった。
【００７６】
実施例２
乾燥窒素気流下、合成例４で合成したＨＦＨＡ２７．２ｇ（０．０４５モル）、ＡＰＤＳ　１．２４ｇ（０．００５モル）をＮＭＰ５０ｇに４０℃で溶解させた。ここに合成例２で合成した３，３’，４，４’−ジフェニルエーテルテトラカルボン酸二無水物１５．１ｇ（マナック（株）製、０．０５モル）を一度に加えた。４０℃で２時間攪拌を続けた後、ジメチルホルムアミドジメチルアセタールＤＭＡ１１．９ｇ（０．１モル）をＮＭＰ３０ｍＬで希釈した溶液を１０分かけて滴下した。
【００７７】
滴下終了後、４０℃で２時間攪拌を続け、その後酢酸１０ｍＬを加え、過剰なＤＭＡを分解した。その後、水１Ｌに投入し白色沈殿を得た。この沈殿をろ過で集め、その後水で２回洗浄した。洗浄後の沈殿を５０℃の真空乾燥機で７２時間乾燥させポリマー２を得た。このポリマー２を１０ｇはかり取り、合成例１で合成した感光剤２ｇ、１，１，２，２−テトラ（４−ヒドロキシフェニル）エタン１ｇをＧＢＬ２０ｇに溶解させた。溶解した後、１μｍのメンブレンフィルターでろ過をした。
【００７８】
この溶液をバンプを形成したウェハーに１２０℃で３分のホットプレート処理後の膜厚が１２μｍになるように大日本スクリーン製造（株）製のＳＣＷ−６３６のコーターを用いてスピンコートした。スピンコート後、１２０℃×３分のホットプレート処理をＳＣＷ−６３６のホットプレートを用いて行った。
【００７９】
このウェハーをキャノン（株）製コンタクトアライナーＰＬＡ−５０１Ａを用いて、３６５ｎｍ、４０５ｎｍ、４３６ｎｍの紫外線が混合した状態で、３６５ｎｍの測定で３０ｍＪ／ｃｍ^２の露光を全面に均一に行った。
【００８０】
本ウェハーを２３℃の２．３８％のテトラメチルアンモニウムヒドロキシド水溶液に入れ、１分間エッチングした。その後水でリンスし、５０Ｌ／分の流量で窒素の流れた光洋サーモシステム製イナートオーブンＩＮＨ−２１ＣＤで１７０℃で３０分、その後５℃／分で昇温し、２８０℃で１時間処理することでウェハー上に耐熱性樹脂であるポリイミド膜を得た。このようにして作成したバンプ表面の炭素濃度は３０原子％、酸素濃度は３１原子％であった。このものの熱分解温度は５２０℃であった。
【００８１】
実施例３
乾燥窒素気流下、１−ヒドロキシベンゾトリアゾール２７．０ｇ（ＨＢＴ、黒金化成（株）製、０．２モル）、トリエチルアミン２０．２ｇ（東京化成（株）製、０．２モル）をＮＭＰ２００ｇに溶解し、３℃に冷却した。この溶液に４，４’−ジフェニルエーテルジカルボン酸ジクロリド２９．５ｇ（ＤＥＤＣ、日本農薬（株）製、０．１モル）をアセトン１００ｇに溶解させた溶液を内温が１０℃を越えないように滴下した。この溶液を３℃で２時間攪拌し、その後室温に上昇して３０分攪拌を続けた。攪拌終了後、溶液をろ過して反応して副生したトリエチルアミンの塩酸塩を除き、ろ液をエバポレーターでアセトンを除去して濃縮した。この濃縮した溶液を水１Ｌに投入して、白色沈殿を得た。この沈殿をろ過で集め、２度水とメタノールで洗浄し、５０度の真空乾燥機で２４時間乾燥した、ＤＥＤＣのＨＢＴエステルを得た。
【００８２】
乾燥窒素気流下、ＢＡＨＦ１８．３ｇ（０．０５モル）、ＤＥＤＣのＨＢＴエステル２３．６ｇ（０．０５モル）をＮＭＰ１５０ｇ、ピリジン１０ｇに溶解させ、７０度で６時間攪拌を続けた。攪拌終了後、溶液を室温に戻し、水３Ｌに投入して白色沈殿を得た。この沈殿を水３Ｌで洗浄し、５０度の真空乾燥機で４８時間乾燥し、ポリヒドロキシアミド（ポリベンゾオキサゾール前駆体）のポリマー粉体を得た。
【００８３】
このポリヒドロキシアミド１０ｇ、合成例１で合成した感光剤２ｇ、１，１，２，２−テトラ（４−ヒドロキシフェニル）エタン１ｇをＧＢＬ２０ｇに溶解させた。溶解した後、１μｍのメンブレンフィルターでろ過をした。
【００８４】
この溶液をバンプを形成したウェハーに１２０℃で３分のホットプレート処理後の膜厚が１２μｍになるように大日本スクリーン製造（株）製のＳＣＷ−６３６のコーターを用いてスピンコートした。スピンコート後、１２０℃×３分のホットプレート処理をＳＣＷ−６３６のホットプレートを用いて行った。
【００８５】
このウェハーをキャノン（株）製コンタクトアライナーＰＬＡ−５０１Ａを用いて、３６５ｎｍ、４０５ｎｍ、４３６ｎｍの紫外線が混合した状態で、３６５ｎｍの測定で３０ｍＪ／ｃｍ^２の露光を全面に均一に行った。
【００８６】
本ウェハーを２３℃の２．３８％のテトラメチルアンモニウムヒドロキシド水溶液に入れ、４５秒間エッチングした。その後水でリンスし、５０Ｌ／分の流量で窒素の流れた光洋サーモシステム製イナートオーブンＩＮＨ−２１ＣＤで１７０℃で３０分、その後５℃／分で昇温し、３２０℃で１時間処理することでウェハー上に耐熱性樹脂であるポリベンゾオキサゾール膜を得た。
【００８７】
この後、ヤマト科学（株）製プラズマリアクターＰＲ−５００を用いて、圧力１ｔｏｒｒ、酸素流量５ｓｃｃｍ、高周波出力３００Ｗで５分間酸素プラズマ処理を行った。バンプ表面の炭素濃度は２０原子％、酸素濃度は３５原子％であった。このものの熱分解温度は４８０℃であった。
【００８８】
実施例４
乾燥窒素気流下、３，３’，４，４’−テトラアミノベンチジン１０．７ｇ（東京化成（株）製、０．０５モル）、実施例３で得たＤＥＤＣのＨＢＴエステル２３．６ｇ（０．０５モル）をＮＭＰ２００ｇ、ピリジン１０ｇに溶解させ、７０度で６時間攪拌を続けた。その後、溶液を４０℃にして、Ｎ−アセチルイミダゾール８．８ｇ（東京化成（株）製、０．０８モル）を加え、４０℃で４時間攪拌続けた。溶液を室温に戻し、水３Ｌに投入して白色沈殿を得た。この沈殿を水３Ｌで洗浄し、５０度の真空乾燥機で４８時間乾燥し、部分的にアセチル化されたポリアミノアミド（ポリベンズイミダゾール前駆体）のポリマー粉体を得た。
【００８９】
このポリアミノアミド１０ｇ、光塩基発生剤としてＡＮＣ−０１（みどり化学（株）製）０．５ｇをＮＭＰ３０ｇに溶解させた。溶解した後、１μｍのメンブレンフィルターでろ過をした。
【００９０】
この溶液をバンプを形成したウェハーに１００℃で４分のホットプレート処理後の膜厚が１２μｍになるように大日本スクリーン製造（株）製のＳＣＷ−６３６のコーターを用いてスピンコートした。スピンコート後、１００℃×４分のホットプレート処理をＳＣＷ−６３６のホットプレートを用いて行った。
【００９１】
このウェハーをキャノン（株）製コンタクトアライナーＰＬＡ−５０１Ａを用いて、３６５ｎｍ、４０５ｎｍ、４３６ｎｍの紫外線が混合した状態で、３６５ｎｍの測定で２Ｊ／ｃｍ^２の露光を全面に均一に行った。露光後、再度ホットプレートで１００℃×１分の加熱を行った。
【００９２】
本ウェハーを２３℃の１％の塩酸水溶液に入れ、９０秒間エッチングした。その後水でリンスし、５０Ｌ／分の流量で窒素の流れた光洋サーモシステム製イナートオーブンＩＮＨ−２１ＣＤで１７０℃で３０分、その後５℃／分で昇温し、２８０℃で１時間処理することでウェハー上に耐熱性樹脂であるポリベンズイミダゾール膜を得た。
【００９３】
この後、ヤマト科学（株）製プラズマリアクターＰＲ−５００を用いて、圧力１ｔｏｒｒ、酸素流量５ｓｃｃｍ、高周波出力３００Ｗで５分間酸素プラズマ処理を行った。バンプ表面の炭素濃度は２２原子％、酸素濃度は３５原子％であった。このものの熱分解温度は５３０℃であった。
【００９４】
実施例５
乾燥窒素気流下、ポリエーテルイミド（日本ＧＥプラスティックス（株）製、ウルテム−１０００）１０ｇ、合成例１で合成した感光剤２ｇ、１，１，２，２−テトラ（４−ヒドロキシフェニル）エタン１ｇをＮＭＰ３０ｇに溶解させた。溶解した後、１μｍのメンブレンフィルターでろ過をした。
【００９５】
この溶液をバンプを形成したウェハーに１００℃で３分のホットプレート処理後の膜厚が１２μｍになるように大日本スクリーン製造（株）製のＳＣＷ−６３６のコーターを用いてスピンコートした。スピンコート後、１００℃×３分のホットプレート処理をＳＣＷ−６３６のホットプレートを用いて行った。
【００９６】
このウェハーをキャノン（株）製コンタクトアライナーＰＬＡ−５０１Ａを用いて、３６５ｎｍ、４０５ｎｍ、４３６ｎｍの紫外線が混合した状態で、３６５ｎｍの測定で１Ｊ／ｃｍ^２の露光を全面に均一に行った。露光後、再度ホットプレートで１００℃×１分の加熱を行った。
【００９７】
本ウェハーを２３℃の５％のテトラメチルアンモニウムヒドロキシド水溶液にＮＭＰを２０％混合した現像液に入れ、１２０秒間エッチングした。その後水でリンスし、５０Ｌ／分の流量で窒素の流れた光洋サーモシステム製イナートオーブンＩＮＨ−２１ＣＤで１７０℃で３０分、その後５℃／分で昇温し、２５０℃で１時間処理した。
【００９８】
この後、ヤマト科学（株）製プラズマリアクターＰＲ−５００を用いて、圧力１ｔｏｒｒ、酸素流量５ｓｃｃｍ、高周波出力３００Ｗで５分間酸素プラズマ処理を行った。バンプ表面の炭素濃度は３０原子％、酸素濃度は２０原子％であった。このものの熱分解温度は４６０℃であった。
【００９９】
実施例６
乾燥空気気流下、３，３’，４，４’−ジフェニルエーテルテトラカルボン酸２無水物１５．５ｇ（マナック（株）製、０．０５モル）、３−ヒドロキシフェニルエタノール１３．８ｇ（東京化成（株）製、０．１モル）をガンマブチロラクトン２００ｍｌとピリジン７．９ｇ（東京化成（株）製、０．１モル）を加え、５０℃で６時間攪拌を続けた。その後、溶液を−１０℃に冷却して、ジシクロヘキシルカルボジイミド２０．６ｇ（東京化成（株）製、０．１モル）をガンマブチロラクトン２００ｍｌに溶解した溶液を内部の温度が０℃を越えないように滴下していった。滴下終了後、−１０℃で３０分攪拌を続け、その後温度を徐々に上げていき、２０℃にした。２０℃で４，４’−ジアミノジフェニルエーテル５．１ｇ（和歌山製化（株）製、０．０４モル）、３，５−ジアミノ安息香酸（東京化成（株）製、０．０１モル）を加えた。このまま、２０℃で２時間、その後４０℃で２時間攪拌を続けた。攪拌終了後、ろ過して反応で生じた副生物を除去し、この溶液を水１０Ｌに投入して、白色沈殿を得た。この沈殿をろ過で集めて、さらに水５Ｌで洗浄した。この白色沈殿を５０℃の真空乾燥機で４８時間乾燥して、ポリアミド酸エステルの粉体を得た。
【０１００】
ポリアミド酸エステル１０ｇ、合成例１で合成した感光剤１　２ｇ、ジフェニルヨードトリフレート０．１ｇ（みどり化学（株）製）をＮＭＰ２０ｇに溶解させた。この溶液を、１μｍのメンブレンフィルターでろ過した。
【０１０１】
この溶液をバンプを形成したウェハーに１１０℃で３分のベーク後の膜厚が１０μｍになるように大日本スクリーン製造（株）製のＳＣＷ−６３６のコーターを用いてスピンコートした。スピンコート後、１１０℃×３分のホットプレート処理をＳＣＷ−６３６のホットプレートを用いて行った。
【０１０２】
キャノン（株）製コンタクトアライナーＰＬＡ−５０１Ａを用いて、３６５ｎｍ、４０５ｎｍ、４３６ｎｍの紫外線が混合した状態で、３６５ｎｍの測定で１００ｍＪ／ｃｍ^２の露光を行った。露光終了後、本ウェハーをＳＣＷ−６３６の現像装置を用いて、２．３８％のテトラメチルアンモニウムヒドロキシド水溶液にて１分間浸漬して、バンプの表面を露出させた。
【０１０３】
５０Ｌ／分の流量で窒素の流れた光陽サーモシステム製イナートオーブンＩＮＨ−２１ＣＤで１７０℃で３０分、その後５℃／分で昇温し、３００℃で１時間を処理することでウェハー上に耐熱性樹脂であるポリイミド膜を得た。
【０１０４】
この後、ヤマト科学（株）製プラズマリアクターＰＲ−５００を用いて、圧力１ｔｏｒｒ、酸素流量５ｓｃｃｍ、高周波出力３００Ｗで５分間酸素プラズマ処理を行った。バンプ表面の炭素濃度は３５原子％、酸素濃度は３５原子％であった。このものの熱分解温度は４４０℃であった。
【０１０５】
比較例１
乾燥窒素気流下、４，４’−ジアミノジフェニルエーテル（和歌山製化（株）製、０．０９５モル）１９．０ｇ、１，３−ビス（３−アミノプロピル）テトラメチルジシロキサン（東レダウコーニングシリコーン（株）製、０．００５モル）１．２ｇをＮＭＰ２００ｇに４０℃で溶解させた。ここに無水ピロメリット酸１０．９ｇ（ダイセル化学（株）製、０．０５モル）、３，３’，４，４’−ベンゾフェノンテトラカルボン酸２無水物１６．１ｇ（ダイセル化学（株）製、０．０５モル）を一度にＮＭＰ５０ｍｌとともに加えた。４０℃で２時間攪拌し、その後、７５℃で３時間攪拌を続けた。反応終了後、１μｍのメンブレンフィルターでろ過した。
【０１０６】
この溶液をバンプを形成したウェハーに１３０℃で３分のベーク後の膜厚が１０μｍになるように大日本スクリーン製造（株）製のＳＣＷ−６３６のコーターを用いてスピンコートした。スピンコート後、１３０℃×３分のホットプレート処理をＳＣＷ−６３６のホットプレートを用いて行った。このウェハーの上にポジ型フォトレジストＯＦＰＲ−８００（東京応化（株）製）を１００℃で９０秒のベーク後の膜厚が２μｍになるように大日本スクリーン製造（株）製のＳＣＷ−６３６のコーターを用いてスピンコートした。スピンコート後、１００℃×９０秒のホットプレート処理をＳＣＷ−６３６のホットプレートを用いて行った。
【０１０７】
キャノン（株）製コンタクトアライナーＰＬＡ−５０１Ａを用いて、３６５ｎｍ、４０５ｎｍ、４３６ｎｍの紫外線が混合した状態で、３６５ｎｍの測定で２００ｍＪ／ｃｍ^２の露光をバンプとその周囲１０μｍの部分にだけ紫外線が照射できるマスクを通して行った。これにより、バンプとその周囲１０μｍだけが露光される。露光終了後、本ウェハーを２３℃の２．３８％のテトラメチルアンモニウムヒドロキシド水溶液に入れ、２分３０秒間、上層部のポジ型フォトレジストをマスクにエッチングした。その後水でリンスし、５０Ｌ／分の流量で窒素の流れた光陽サーモシステム製イナートオーブンＩＮＨ−２１ＣＤで１７０℃で３０分、その後５℃／分で昇温し、３５０℃で１時間処理することでウェハー上に耐熱性樹脂であるポリイミド膜を得た。
【０１０８】
この後、ヤマト科学（株）製プラズマリアクターＰＲ−５００を用いて、圧力１ｔｏｒｒ、酸素流量５ｓｃｃｍ、高周波出力３００Ｗで５分間酸素プラズマ処理を行った。
【０１０９】
本法で作成したウェハーからチップ上に切断する際に、削り屑の一部が、バンプとポリイミドの保護膜の間に入り込んでおり、半導体チップ表面を傷つける恐れがあった。このバンプ表面の炭素濃度は３０原子％であったが、酸素濃度は４５原子％と多くなっていた。このものの熱分解温度は５６０℃であった。
【０１１０】
比較例２
バンプとその周囲１μｍの部分にだけ紫外線が照射できるマスクを通して行った以外は比較例１と同じ条件でバンプ形成したウェハー上にポリイミド膜を形成した。本法で作成したバンプ上には、ポリイミドが部分的に付着しており、評価することが出来なかった。
【０１１１】
比較例３
乾燥空気気流下、無水ピロメリット酸１０．９ｇ（ダイセル化学（株）製、０．０５モル）、３，３’，４，４’−ベンゾフェノンテトラカルボン酸２無水物１６．１ｇ（ダイセル化学（株）製、０．０５モル）、２−ヒドロキシエチルメタクリレート２７．６ｇ（東京化成（株）製、０．２モル）をガンマブチロラクトン２００ｍｌとピリジン１５．８ｇ（東京化成（株）製、０．２モル）を加え、５０℃で６時間攪拌を続けた。その後、溶液を−１０℃に冷却して、ジシクロヘキシルカルボジイミド４１．２ｇ（東京化成（株）製、０．２モル）をガンマブチロラクトン２００ｍｌに溶解した溶液を内部の温度が０℃を越えないように滴下していった。滴下終了後、−１０℃で３０分攪拌を続け、その後温度を徐々に上げていき、２０℃にした。２０℃で４，４’−ジアミノジフェニルエーテル２０．０ｇ（和歌山製化（株）製、０．１モル）を加えた。このまま、２０℃で２時間、その後４０℃で２時間攪拌を続けた。攪拌終了後、ろ過して反応で生じた副生物を除去し、この溶液を水１０Ｌに投入して、白色沈殿を得た。この沈殿をろ過で集めて、さらに水５Ｌで洗浄した。この白色沈殿を５０℃の真空乾燥機で４８時間乾燥して、ポリアミド酸エステルの粉体を得た。
【０１１２】
ポリアミド酸エステル１０ｇ、Ｎ−フェニルグリシン０．２ｇ（東京化成（株）製）、イルガキュア３６９　０．２ｇ（チバスペシャリティーケミカル（株）製）、エチレングリコールジメタクリレート１ｇ（新中村化学（株）製）をＮＭＰ２０ｇに溶解させた。この溶液を、１μｍのメンブレンフィルターでろ過した。
【０１１３】
この溶液をバンプを形成したウェハーに９５℃で３分のベーク後の膜厚が１０μｍになるように大日本スクリーン製造（株）製のＳＣＷ−６３６のコーターを用いてスピンコートした。スピンコート後、９５℃×３分のホットプレート処理をＳＣＷ−６３６のホットプレートを用いて行った。
【０１１４】
キャノン（株）製コンタクトアライナーＰＬＡ−５０１Ａを用いて、３６５ｎｍ、４０５ｎｍ、４３６ｎｍの紫外線が混合した状態で、３６５ｎｍの測定で２００ｍＪ／ｃｍ^２の露光をバンプとその周囲１０μｍの部分にだけ覆われ、他は通すマスクを通して行った。これにより、バンプとその周囲１０μｍだけが露光されない。露光終了後、本ウェハーをＳＣＷ−６３６の現像装置を用いて、ＮＭＰが６０部、キシレンが３７部、水が３部の現像液をウェハーを２０００回転で回転させながらスプレーで６０秒間噴霧した。その後、イソプロピルアルコールを１０秒間２０００回転で回転させながらスプレー噴霧し、最後に３０００回転で回転して乾燥させ、バンプだけポリイミド前駆体膜の無いパターンを形成した。
【０１１５】
５０Ｌ／分の流量で窒素の流れた光陽サーモシステム製イナートオーブンＩＮＨ−２１ＣＤで１７０℃で３０分、その後５℃／分で昇温し、３８０℃で１時間処理することでウェハー上に耐熱性樹脂であるポリイミド膜を得た。
【０１１６】
本法で作成したウェハーからチップ上に切断する際に、削り屑の一部が、バンプとポリイミドの保護膜の間に入り込んでおり、半導体チップ表面を傷つける恐れがあった。このバンプ表面の炭素濃度は４５原子％、酸素濃度は５０原子％と非常に多かった。このものの熱分解温度は５２０℃であった。
【０１１７】
比較例４
乾燥窒素気流下、４，４’−ジアミノジフェニルエーテル（和歌山製化（株）製、０．１２モル）２４．２ｇをＮＭＰ１５０ｇに４０℃で溶解させた。ここに無水ピロメリット酸２６．４ｇ（ダイセル化学（株）製、０．１２モル）を加えた。４０℃で２時間攪拌し、その後、トルエン（和光純薬（株）製）５０ｍｌを加えて、１５０℃で４時間、共沸で系外に出てくる水とトルエンを除きながら攪拌を続けた。反応終了後、溶液を攪拌したまま３０℃以下に冷却した。４，４’−ジアミノジフェニルエーテル（和歌山製化（株）製、０．０９５モル）１９．０ｇ、１，３−ビス（３−アミノプロピル）テトラメチルジシロキサン（東レダウコーニングシリコーン（株）製、０．００５モル）１．２ｇを溶解させ、ここに３，３’，４，４’−ジフェニルエーテルテトラカルボン酸２無水物３１．０ｇ（マナック（株）製、０．１モル）をＮＭＰ２０ｍｌとともに加え、５０℃で４時間攪拌した。
【０１１８】
この溶液をバンプを形成したウェハーにスクリーン印刷機を用いて、バンプの部分とその周囲１０μｍの部分に塗布されないようにしたステンレス製のスクリーンを用いて、硬化後の膜厚が２０μｍになるように塗布した。
【０１１９】
このウェハーを５０Ｌ／分の流量で窒素の流れた光陽サーモシステム製イナートオーブンＩＮＨ−２１ＣＤで８０℃で６０分、その後５℃／分で昇温し、３５０℃で１時間処理することでウェハー上に耐熱性樹脂であるポリイミド膜を得た。
【０１２０】
この後、ヤマト科学（株）製プラズマリアクターＰＲ−５００を用いて、圧力１ｔｏｒｒ、酸素流量５ｓｃｃｍ、高周波出力３００Ｗで５分間酸素プラズマ処理を行った。
【０１２１】
本法で作成したウェハーからチップ上に切断する際に、削り屑の一部が、バンプとポリイミドの保護膜の間に入り込んでおり、半導体チップ表面を傷つける恐れがあった。また、スクリーン印刷の精度が十分でなく、一部のバンプの表面にポリイミドが付着しており、電気抵抗が測定できないバンプがあった。このバンプ表面の炭素濃度は２０〜４０原子％、酸素濃度は３０〜４５原子％とバラツキが大きく、全体的に酸素分が多めであった。このものの熱分解温度は５４０℃であった。
【０１２２】
比較例５
カルボキシル基と不飽和基を有したアクリル樹脂であるサイクロマーＰ　ＡＣＡ２００（ダイセル化学（株）製）１０ｇ、合成例１で合成した感光剤３ｇ、１，１，２，２−テトラ（４−ヒドロキシフェニル）エタン１ｇ、架橋剤としてヘキサメトキシメチルメラミン（三井サイテック（株）製、サイメル３００）１ｇをガンマブチロラクトン（ＧＢＬ）１０ｇとプロピレングリコールモノメチルエーテルアセテート１０ｇに溶解させた。溶解した後、１μｍのメンブレンフィルターでろ過をした。
【０１２３】
この溶液をバンプを形成したウェハーに９５℃で３分のベーク後の膜厚が１０μｍになるように大日本スクリーン製造（株）製のＳＣＷ−６３６のコーターを用いてスピンコートした。スピンコート後、９５℃×３分のホットプレート処理をＳＣＷ−６３６のホットプレートを用いて行った。
【０１２４】
キャノン（株）製コンタクトアライナーＰＬＡ−５０１Ａを用いて、３６５ｎｍ、４０５ｎｍ、４３６ｎｍの紫外線が混合した状態で、３６５ｎｍの測定で５０ｍＪ／ｃｍ^２の露光を行った。露光終了後、２３℃の０．５％のテトラメチルアンモニウムヒドロキシド水溶液に１分間浸漬してバンプ表面を露出させた。
【０１２５】
５０Ｌ／分の流量で窒素の流れた光洋サーモシステム製イナートオーブンＩＮＨ−２１ＣＤで２００℃で３０分処理することでウェハー上に架橋して耐熱性を向上させたアクリル樹脂膜を得た。
【０１２６】
このバンプ表面の炭素濃度は５０原子％、酸素濃度は４０原子％と非常に多かった。このものの熱分解温度は２８０℃と低かった。
【０１２７】
【発明の効果】
本発明により、信頼性の高い半導体装置を提供することができる。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for manufacturing a semiconductor device and a semiconductor device. In particular, the present invention relates to a semiconductor device having a bump structure which is important for miniaturization and thinning of mounting.
[0002]
[Prior art]
As semiconductors and electronic devices become smaller and thinner, terminals (convex electrodes) made of solder or gold, called bumps, are formed on the pads of semiconductor devices, and these are directly surface-bonded to the substrate. Has been implemented as flip chip technology.
[0003]
When such a bump is formed and joined, it is widely practiced to form a bump of solder or gold after forming a circuit of a semiconductor element, and to mount the bump. However, in such a method, when the semiconductor element and the substrate are joined, the passivation film formed of silicon nitride or the like that protects the inside of the semiconductor element comes into contact with the substrate, causing cracks or contamination of the electrodes. There has been a problem that the reliability of the semiconductor element is reduced.
[0004]
On the other hand, a film made of a heat-resistant organic resin such as polyimide is formed to protect the passivation film and to prevent cutting chips from entering the electrode (for example, see Patent Document 1). However, in such a method, a gap is formed between the bump and the bump protective film, and there is a problem that dust generated when the wafer is cut into chips enters the gap. In addition, it is necessary to expose the bump pattern through a mask. The required resolution was not obtained due to the step of about 5 to 100 μm of the bump, and it was difficult to form an accurate pattern.
[0005]
Further, as a simple method, a method of forming a protective film by a printing method such as screen printing has been proposed (for example, see Patent Document 2). However, even with this method, the gap between the bump and the protective film cannot be eliminated due to the printing accuracy. In addition, such a material for screen printing usually contains particles such as silica and polyimide in a coating liquid, which may become foreign matters, and is not preferable in terms of reliability.
[0006]
Further, there is a method in which a heat-resistant resin film such as polyimide is formed after the bump is formed, and the tip of the bump is sharpened in order to expose the bump from the film (for example, see Patent Document 3). With the shape of the bump, it is difficult to bond the bump to the external substrate as it is, and a bump for bonding to the outside is formed again on the bump and the protective film, and the process is complicated.
[0007]
Also, a method is known in which a heat-resistant resin film such as polyimide is formed after bump formation, and then the back surface of the bumped wafer is polished, and then the heat-resistant resin film is lightly etched to expose the bumps. (For example, see Patent Document 4). However, with this method, uniform etching is difficult to proceed with simple wet etching, and the film thickness tends to vary, dry etching takes time, and the use of fluorine-based reactive gas contaminates the bump surface. However, there are problems such as an increase in electric resistance.
[0008]
[Patent Document 1]
JP 2001-274129 A (pages 1 to 3)
[0009]
[Patent Document 2]
JP 2000-323174 A (pages 11 to 12)
[0010]
[Patent Document 3]
JP-A-2002-110854 (p. 3)
[0011]
[Patent Document 4]
JP-A-5-55278 (page 3)
[0012]
[Problems to be solved by the invention]
In view of such a situation, an object of the present invention is to provide a method for manufacturing a semiconductor element with a convex electrode that provides high reliability without generating a gap between the convex electrode and the protective film, and a semiconductor element.
[0013]
[Means for Solving the Problems]
That is, the present invention relates to a method of manufacturing a semiconductor device having a convex electrode for external connection and a protective film having a thermal decomposition temperature of 300 ° C. or higher and a heat-resistant resin as a main component, wherein the convex electrode is formed. After applying the positive photosensitive heat-resistant resin composition or its precursor composition to the subsequent semiconductor element, exposing the entire surface, and then developing until the surface of the convex electrode appears, then curing the semiconductor device. It is a manufacturing method.
[0014]
Another aspect of the present invention is a semiconductor device having an electrode for external connection and a protective film, wherein no gap exists between the electrode exposed from the protective film and the protective film, and A semiconductor device whose oxygen concentration by the XPS method is 40 atomic% or less is the main feature.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
In the present invention, a semiconductor element is formed by a known method, and a bump as a convex electrode is formed thereon. As the bump, there are a method using solder, a method using gold and copper, and the like, but other materials may be used. As a method for forming such a bump, there are a vapor deposition method, a plating method, a paste printing method and the like, and the present invention can use any of these methods. Among these, in the present invention, since the heat-resistant resin composition is applied and processed after the formation of the bump, it is preferable to use a gold bump having low reactivity and being hard to be deformed.
[0016]
After the formation of the bumps as the convex electrodes, a positive photosensitive heat-resistant resin composition or a precursor composition thereof is applied substantially uniformly over the entire surface. Examples of the application method include spin coating, dip, spray, potting, slit application, electrodeposition, and printing, and any other method may be used as long as it can be applied uniformly on the substrate. Generally, a spin coating method is preferably used from the viewpoint of uniformity.
[0017]
The positive photosensitive heat-resistant resin composition or its precursor composition is preferably diluted with a solvent in order to be used for coating. Although the solvent to be used is not particularly limited, for example, dipolar aprotic solvents such as N-methylpyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide, gamma-butyrolactone, and dimethylimidazoline are preferable. Further, one or more of propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, ethyl lactate, cyclohexanone, cyclopentanone, sulfolane, diethyl carbonate, and propylene carbonate can be used. The solution after solvent dilution is preferably substantially uniform, and more preferably less than 1% of undissolved matter.
[0018]
As the heat-resistant resin or its precursor to be used, for example, polyimide, polyimide precursor (polyamic acid, polyamic acid ester, polyisoimide, etc.), polybenzoxazole, polybenzoxazole precursor (polyhydroxyamide, polyazomethine, etc.), Examples include polybenzimidazole, a polybenzimidazole precursor (such as polyaminoamide), polybenzothiazole, a polybenzothiazole precursor (such as polythiophenolamide), polyetherimide, polyetherketone, and polysulfone. Preferred examples of the heat-resistant resin precursor are shown in the following formula (1).
[0019]
Embedded image

[0020]
(Where R ¹ Is a divalent to hexavalent organic group having 2 to 30 carbon atoms. R ² Is a divalent to hexavalent organic group having 2 to 40 carbon atoms. R ³ , R ⁴ Is a group containing at least one selected from hydrogen, a monovalent organic group having 1 to 20 carbon atoms, and a group eliminated by an acid or alkali. Y and Z are a hydroxyl group, an ether group, an amino group, an amide group, a thiol group, a monovalent group containing at least one selected from thioether groups, a, b, c, and d are integers of 0 to 4, a + b + c + d> 0. n is an integer from 10 to 1,000,000).
[0021]
The method for producing the heat-resistant resin or its precursor used in the present invention is not particularly limited, and a known method can be used.
[0022]
In the present invention, since the resin composition is entirely covered after the formation of the bumps, the resin composition preferably has high heat resistance. If the heat resistance is low, for example, contamination of the bumps by an organic substance during the heat treatment becomes a problem.
[0023]
For this reason, the protective film used in the present invention needs to contain a heat-resistant resin having a thermal decomposition temperature of 300 ° C. or higher as a main component. Here, the main component means that it is 60 mol% or more. Preferably, the resin component is composed of the above-described heat-resistant resin or a precursor composition thereof, but other resin components may be added as long as the effects of the present invention are not impaired.
[0024]
When an organic substance contaminates the surface of the bump, the electrical resistance of the bump increases. This electric resistance preferably increases by 300% or less after heat treatment, more preferably 200% or less, before heat treatment.
[0025]
The electric resistance of the bump is preferably 1 KΩ or less, more preferably 500 Ω or less. If the electric resistance is large, the connection to the outside becomes insufficient, and a problem tends to occur in the operation of the product.
[0026]
When the electric resistance increases, it is possible to add a step of lowering the electric resistance by oxygen plasma treatment, argon reverse sputtering treatment, high-temperature treatment in a reducing atmosphere, wet treatment with an acid, alkali, organic solvent, or the like. These processes are common in the semiconductor industry.
[0027]
The contamination level of the bump can be measured by measuring the metal concentration, the carbon concentration, the oxygen concentration, and the like on the bump surface by using the XPS method (X-ray photoelectron spectroscopy). The carbon concentration on the bump surface is preferably at most 40 at%, more preferably at most 30 at%.
[0028]
The oxygen concentration on the bump surface by the XPS method is preferably 40 atomic% or less. If the oxygen content is high, it is difficult to remove from the bump surface, and a hard metal oxide is formed, which is not preferable. From such a point, the oxygen concentration on the bump surface is more preferably 35 atomic% or less.
[0029]
Further, since fluorine and sulfur cause corrosion, the total content is preferably 10 atomic% or less, more preferably 5 atomic% or less.
[0030]
The glass transition temperature of the heat-resistant resin used in the present invention is preferably 240 ° C. or more and 400 ° C. or less. If the temperature is lower than 240 ° C., deformation occurs at the time of soldering, which may give stress to the bumps. If the temperature is higher than 400 ° C., the adhesion to the underlying substrate is deteriorated, which causes a problem in reliability. A more preferred range is from 250 ° C to 380 ° C, particularly preferably from 260 ° C to 350 ° C. Here, the glass transition temperature can be measured by a general method using a differential thermal analysis (DSC) at a heating rate of 10 ° C./min.
[0031]
In order to uniformly expose the bumps, it is necessary that the photosensitive composition be a positive type in which the dissolution rate of the exposed portion of the heat-resistant resin composition or its precursor composition increases. Positive photosensitivity means that after low-illumination full-surface exposure, the bump quickly dissolves during development until the bump surface comes out, and then the development speed drops significantly. You can get it.
[0032]
A photosensitizer is added to make a positive type photosensitivity. The photosensitizer is not particularly limited, but a photosensitizer which generates an acid upon irradiation with light is preferably used. And at least one compound selected from the group consisting of an ester compound, an onium salt, a halogen-containing compound, a diazoketone compound, a diazomethane compound, a sulfone compound, a sulfonate compound, and a sulfonimide compound with respect to the heat-resistant resin composition. It is preferable to mix by weight%.
[0033]
After the application of the heat-resistant resin composition or its precursor composition, a pre-bake step can be performed for drying the solvent and the like. Prebaking conditions are preferably 30 seconds to 20 minutes when using a hot plate at a temperature of 30 ° C. to 200 ° C., and 5 minutes to 2 hours when using an oven.
[0034]
Thereafter, the entire surface is exposed. The wavelength to be exposed may be any wavelength as long as the sensitivity is sufficient, but g-line (436 nm), h-line (405 nm), i-line (365 nm) of a high-pressure mercury lamp is preferably used. In addition, ultraviolet light (254 nm) of an ultra-high pressure mercury lamp, ultraviolet light (248 nm) by KrF excimer, ultraviolet light (193 nm) by ArF excimer, F ₂ Ultraviolet light (157 nm) by an excimer, Ar ion laser (532 nm), a xenon lamp (continuous light), or the like can also be used. Further, such ultraviolet rays can be selectively irradiated with only one wavelength, or can be irradiated by mixing a plurality of wavelengths.
[0035]
The exposure amount is not particularly limited, but is preferably low illuminance. That is, after development, the bumps are preferably exposed from the surface by about 0.5 μm to 10 μm, and it is necessary to irradiate the entire surface with a smaller exposure amount than the positive heat-resistant resin composition or its precursor composition is completely dissolved. Because there is. Such an exposure amount varies depending on a target film thickness of the protective film, but an exposure amount of about 1/10 to 1/2 that in the case of forming a general pattern is preferably used. As described above, according to the present invention, not only the mask is not required but also the exposure amount can be reduced.
[0036]
After exposure, develop. The developer used for the development is not particularly limited. For example, an aqueous solution of an organic alkali such as tetramethylammonium hydroxide, monoethanolamine, diethylaminoethanol, or choline, or an inorganic solution such as sodium hydroxide, potassium hydroxide, potassium carbonate, or sodium carbonate. Alkaline aqueous solution, aqueous solution of organic acid such as acetic acid, benzoic acid and oxalic acid, aqueous solution of inorganic acid such as hydrochloric acid, sulfuric acid and nitric acid, N-methyl-2-pyrrolidone and N, N-dimethylacetamide which are dipolar aprotic solvents , N, N-dimethylformamide, dimethyl sulfoxide, gamma-butyrolactone, alcohols such as methanol, ethanol, diacetone alcohol, ethylene glycol, propylene glycol monomethyl ether, acetone, methyl ethyl ketone, methyl ethyl Ketones such as ketone, ethyl acetate, butyl acetate, ethyl lactate, ethylene glycol monomethyl ether acetate, a mixture of esters such as propylene glycol monomethyl ether acetate.
[0037]
The development conditions are not particularly limited, and conditions under which development can be performed until a bump surface appears can be appropriately selected.
[0038]
After the bump surface is exposed by development, it is cured. Here, curing refers to a step of subjecting a film made of a heat-resistant resin composition or a precursor composition thereof to heat treatment, electromagnetic wave treatment, chemical treatment, ultraviolet treatment, or the like, to convert the film into a chemical-resistant film.
[0039]
As a cure, when performing heat treatment, when using an oven in the range of 150 ° C. to 450 ° C., perform the treatment at the maximum temperature for 5 minutes to 2 hours, and in the case of the hot plate treatment, perform the treatment at the maximum temperature for about 30 seconds to 20 minutes. It is preferred to do so. When performing electromagnetic wave treatment, it is preferable to apply a high frequency of about 1 GHz to 30 GHz at an output of 10 W to 10 kW for 5 seconds to 1 hour.
[0040]
The atmosphere in which the heat treatment and the electromagnetic wave treatment are performed is not particularly limited. For example, the treatment is performed in air, in an inert gas such as nitrogen, argon, or helium, in a reducing gas atmosphere in which a hydrogen gas is mixed with an inert gas, in a vacuum, or the like. I can do it. The pressure at the time of such a process can be any from a high vacuum of 0.1 torr or less to a high pressure of about 1000 atm.
[0041]
Further, in the case of performing treatment with a chemical as a cure, in the case of a film made of a heat-resistant resin precursor composition, it is preferable to use a catalyst for converting the heat-resistant resin precursor into a heat-resistant resin as the chemical. As the catalyst, for example, organic bases such as pyridine, triethylamine, piperidine, imidazole, pyrazole and tetrazole, boron salts, acid compounds such as phosphoric acid, polyphosphoric acid, methanesulfonic acid and trifluoroacetic acid are preferably used. The reaction is usually carried out at a temperature from room temperature to about 400 ° C. The atmosphere, pressure, and the like can be the same conditions as in the above heat treatment.
[0042]
When performing treatment with a chemical, it is preferable to perform a chemical treatment for crosslinking the heat-resistant resin in order to further improve the chemical resistance. Examples of compounds used for such chemical treatment include dimethylol compounds, bismaleimides, diethynylbenzene, acrylic monomers, and alkoxysilanes. In these treatments, the temperature is applied from room temperature to about 400 ° C., and the same conditions as those of the above heat treatment can be used for the atmosphere, pressure, and the like.
[0043]
Crosslinking with UV light can also improve chemical resistance. As such ultraviolet rays, ultraviolet rays from 150 nm to 500 nm, electron beams, γ rays, and the like can be used. UV energy is 10mJ / cm ² -10 J / cm ² Of energy can preferably be used. In order to increase the crosslinking efficiency by ultraviolet irradiation, dimethylol compounds, bismaleimides, diethynylbenzene, acrylic monomers, alkoxysilanes, etc. can be added, and bis (4-dimethylaminophenyl) ketone as a sensitizer, Benzophenone, benzoin methyl ether, onium salts and the like can also be added. In these treatments, the temperature is applied from room temperature to about 400 ° C., and the same conditions as those of the above heat treatment can be used for the atmosphere, pressure, and the like.
[0044]
As the crosslinking of the heat-resistant resin proceeds, the shrinkage stress increases, and the adhesiveness to the metal tends to decrease. In order to improve this and improve the adhesion to the metal, a compound having both a group that forms a complex with the metal and a group that reacts with the resin can be added to the composition. Specifically, for example, a cyano group, an amino group, a thiol group or a derivative group thereof which forms a complex with a metal at a high temperature treatment of 200 ° C. or more, and an amino group, a carboxyl group, an ester group, a hydroxyl group which reacts with a heat-resistant resin A method of adding a compound having a sulfonyl group or the like to the heat-resistant resin in an amount of 0.5 to 20% by weight is preferably used. If it is less than 0.5%, it is difficult to obtain an effect, and if it exceeds 20% by weight, chemical resistance and heat resistance tend to decrease, which may cause cracks and contamination of bumps. Particularly preferred as these compounds are dicyanoaniline, dithiobenzoic acid, cyanophenol, aminocyanopropane, aminothiophenol, thiocyanopropane, ethylenediamine, ethylenediamine diacetate, ethylenediaminetetraacetic acid, cyanophenylsulfonic acid, and thiophenylcarboxylic acid. and so on. Particularly, aminocyanopropane, aminothiophenol, thiocyanopropane, ethylenediamine, ethylenediamine diacetate and the like are preferable.
[0045]
By using the method of the present invention, a semiconductor device having no gap between an exposed electrode and a protective film can be easily manufactured.
[0046]
Next, the semiconductor device of the present invention will be described.
[0047]
The semiconductor device of the present invention is a semiconductor device having an electrode for external connection and a protective film, wherein there is no gap between the electrode exposed from the protective film and the protective film, and the XPS on the surface of the electrode. This is a semiconductor device having an oxygen concentration of 40 atomic% or less according to a method.
[0048]
Here, the absence of the gap does not deny the existence of the depression. If there is a depression, the depth is preferably 50% or less of the thickness of the protective film, more preferably 30% or less.
[0049]
In the semiconductor device of the present invention, chips generated when a semiconductor element is cut into chips do not enter gaps, thereby preventing defects. Further, since the entire surface other than the bumps can be covered with the protective film, the impact of the bumps can be reduced. It is possible to provide a semiconductor device having a high protection effect and higher reliability.
[0050]
The semiconductor device of the present invention can be easily manufactured by, for example, the above manufacturing method, but is not limited thereto.
[0051]
The protective film is preferably a protective film obtained by curing a heat-resistant resin composition having positive photosensitivity or a precursor composition thereof.
[0052]
In the semiconductor device of the present invention, when there is a redundant circuit on the semiconductor element and it is necessary to cut it by an operation test, the fuse of the redundant circuit can be cut by a laser or the like by eliminating the protective film only in that portion. . In this case, a necessary pattern can be formed by a single development process by performing exposure for sufficiently reacting only the fuse portion to the bottom of the protective film, and performing a small amount of exposure for the other portions. The same can be used for forming scribe lines and the like.
[0053]
After forming the protective film in this manner, it is general that the semiconductor element is cut into chips, but it is also possible to form a protective film on the element cut into chips by the above method.
[0054]
The method of mounting the semiconductor element on the substrate is not particularly limited, but in the case of the semiconductor device of the present invention, it is general that the semiconductor device is connected by flip-chip connection.
[0055]
The semiconductor device of the present invention can be used for, for example, a small liquid crystal display element, a liquid crystal display element requiring a thin film, a video camera, a mobile phone, a digital camera, and the like.
[0056]
【Example】
Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited thereto. In addition, evaluation of the heat resistant resin composition in an Example was performed by the following method.
[0057]
(Measurement of oxygen concentration on electrode surface)
A substrate in which a gold bump having a diameter of 20 μm and a height of 10 μm was formed on a 4-inch silicon wafer was prepared. Here, a varnish of the photosensitive heat-resistant resin composition and the photosensitive heat-resistant resin precursor composition was pre-baked at 120 ° C. for 3 minutes using a coating apparatus of a coating and developing apparatus SCW-636 manufactured by Dainippon Screen Mfg. Co., Ltd. Thereafter, spin coating was performed so that the film thickness became 12 μm, and treatment was performed at 120 ° C. for 3 minutes using the same SCW-636 hot plate. Exposure was performed under predetermined conditions using a contact aligner PLA-501 manufactured by Canon Inc. After the exposure, the pad was immersed in a predetermined developer for a predetermined time to expose the top of the pad, and then rinsed with ultrapure water.
[0058]
The wafer on which the pattern is formed as described above is placed in an inert oven INH-21CD manufactured by Koyo Thermo System Co., Ltd., and treated at 140 ° C. for 30 minutes in a nitrogen gas atmosphere having an oxygen concentration of 20 ppm or less, and then at 3.5 ° C./min. The temperature was raised and the treatment was performed at a temperature in the range of 250 ° C. to 350 ° C. for 60 minutes.
[0059]
By using SSX-100 (manufactured by SSI), the exposed portion of the gold by this pattern formation was excited to X-rays using single crystal aluminum Kα1,2 lines (1486.6 eV), X-ray diameter 1 mm, X-ray output 10 kV, At 20 mA, the angle of the detector was set to 45 degrees, and the C1s peak position of neutral carbon was adjusted to 284.6 eV to analyze the elements adhering to the gold. The peak attributed to oxygen O1s appears in the range of 525 eV to 535 eV.
[0060]
(Measurement of thermal decomposition temperature)
A photosensitive heat-resistant resin composition and a varnish of a photosensitive heat-resistant resin precursor composition are applied to a 4-inch silicon wafer at 120 ° C. using a coating apparatus of a coating and developing apparatus SCW-636 manufactured by Dainippon Screen Mfg. Co., Ltd. The substrate was spin-coated so that the film thickness after pre-baking for 8 minutes became 8 μm, and treated at 120 ° C. for 3 minutes using the same SCW-636 hot plate. The wafer was heated at 170 ° C. for 30 minutes in an inert oven INH-21CD manufactured by Koyo Thermo System Co., Ltd., then heated to 350 ° C. at a rate of 3.5 ° C./min, and treated at 350 ° C. for 1 hour. It cooled naturally until it became below. Thereafter, the wafer was taken out of the oven.
[0061]
The cured film with the wafer was immersed in 47% hydrofluoric acid (special grade, manufactured by Wako Pure Chemical Industries, Ltd.) for 5 minutes, washed with tap water, peeled from the silicon wafer, and then removed from Yamato Scientific Co., Ltd. Heat treatment was performed at 200 ° C. for 1 hour using an inert oven DT-42 to remove absorbed water.
[0062]
About 10 mg of the cured film of the heat-resistant resin composition is rolled, put into a platinum cell, and put into a thermogravimetric analyzer TG-50 manufactured by Shimadzu Corporation at room temperature at a rate of 10 ° C./min. From 800 ° C. to 800 ° C., and the point at which the weight loss occurred by 5% was defined as the pyrolysis temperature.
[0063]
Synthesis Example 1: Synthesis of naphthoquinonediazide compound 1
Under dry nitrogen flow, 21.2 g (0.05) of 4,47- [1- [4- [1- (4-hydroxyphenyl) -1-methylethyl] phenyl] ethylidene) bisphenol (manufactured by Honshu Chemical Co., Ltd.) Mol) and 32.2 g (0.12 mol) of 5-naphthoquinonediazidosulfonyl chloride (manufactured by Toyo Gosei Co., Ltd.) were dissolved in 500 g of 1,4-dioxane (manufactured by Hayashi Junyaku Co., Ltd.), and heated to 40 ° C. Heated. Here, 12.1 g (0.12 mol) of triethylamine (manufactured by Wako Pure Chemical Industries, Ltd.) mixed with 50 g of 1,4-dioxane was added dropwise so that the temperature in the system did not become 45 ° C. or more. After the addition, the mixture was stirred at 40 degrees for 2 hours. The by-product triethylamine hydrochloride was filtered, and the filtrate was poured into 3 liters of 1% hydrochloric acid. Thereafter, the deposited precipitate was collected by filtration. Further, the washing was repeated twice with 10 l of water and dried with a vacuum dryer at 50 ° C. for 20 hours to obtain a naphthoquinonediazide compound.
[0064]
Synthesis Example 2: Synthesis of naphthoquinonediazide compound 2
Under a dry nitrogen stream, 19.9 g (0.05 mol) of 1,1,2,2-tetra (4-hydroxyphenyl) ethane (manufactured by Honshu Chemical Co., Ltd.) and 5-naphthoquinonediazidosulfonyl chloride (Toyo Gosei Co., Ltd.) (34.9 g, 0.13 mol) was dissolved in 500 g of 1,4-dioxane (manufactured by Hayashi Junyaku Co., Ltd.) and heated to 40 ° C. Here, 13.1 g (0.13 mol) of triethylamine (manufactured by Wako Pure Chemical Industries, Ltd.) mixed with 50 g of 1,4-dioxane was added dropwise so that the temperature in the system did not become 45 ° C. or more. After the addition, the mixture was stirred at 40 degrees for 2 hours. The by-product triethylamine hydrochloride was filtered, and the filtrate was poured into 3 liters of 1% hydrochloric acid. Thereafter, the deposited precipitate was collected by filtration. Further, the washing was repeated twice with 10 l of water and dried with a vacuum dryer at 50 ° C. for 20 hours to obtain a naphthoquinonediazide compound.
[0065]
Synthesis Example 3: Synthesis of acid anhydride 1 (TMDA)
A 2-L (3-amino-4-hydroxyphenyl) hexafluoropropane (manufactured by Central Glass Co., Ltd .; hereinafter, abbreviated as BAHF) is placed in a 1 L three-necked flask equipped with a stirring blade, a thermometer, and a nitrogen inlet tube. 18.3 g (0.05 mol) was weighed, and acetone (dissolved in 300 mL; glycidyl methyl ether (manufactured by Tokyo Chemical Industry Co., Ltd .; hereinafter abbreviated as GME)) 80 g (0.91 mol). In addition, the temperature of the solution was cooled to 5 ° C. Here, 21.1 g (0.1 mol) of trimellitic anhydride chloride (manufactured by Tokyo Chemical Industry Co., Ltd.) was added to 200 mL of acetone (special grade, manufactured by Sasaki Chemical Co., Ltd.). Was added dropwise over 15 minutes such that the temperature of the solution did not exceed 10 ° C.
[0066]
After the dropwise addition, the mixture was stirred at 5 ° C for 2 hours, and then heated to 25 ° C over 30 minutes. After stirring at 25 ° C. for 30 minutes, filtration was performed, and a yellow precipitate was collected. The collected precipitate was further washed twice with acetone. The precipitate was dried with a vacuum dryer at 80 ° C. for 24 hours to obtain the indicated acid anhydride 1 (TMDA).
[0067]
Synthesis Example 4: Synthesis of diamine 1 (HFHA)
18.3 g (0.05 mol) of BAHF was weighed and dissolved in 200 mL of acetone in a 2 L three-necked flask equipped with a stirring blade, a thermometer, and a nitrogen inlet tube. To this, 80 mL (0.91 mol) of GME was added, and the temperature of the solution was cooled to 5 ° C. Here, a solution prepared by dissolving 18.6 g (0.1 mol) of 3-nitrobenzoic acid chloride (manufactured by Tokyo Chemical Industry Co., Ltd.) in 200 mL of acetone is used for 15 minutes so that the temperature of the solution does not exceed 10 ° C. It was dropped.
[0068]
After the dropwise addition, the mixture was stirred at 5 ° C for 2 hours, and then heated to 25 ° C over 30 minutes. After stirring at 25 ° C. for 30 minutes, filtration was performed to collect a precipitate. The collected precipitate was further washed twice with acetone. This precipitate was recrystallized from methyl benzoate and dried in a vacuum dryer at 100 ° C. for 48 hours to obtain 33 g of a white powder.
[0069]
13.4 g of the white powder was weighed, and a mixed solvent of 100 mL of tetrahydrofuran (manufactured by Wako Pure Chemical Industries, Ltd.) and 50 mL of methanol (manufactured by Katayama Chemical Co., Ltd.) was dissolved at 40 ° C. 0.2 g of 5% palladium-carbon (manufactured by Wako Pure Chemical Industries, Ltd.) was added thereto, and 8 g of saturated hydrazine (manufactured by Wako Pure Chemical Industries, Ltd.) was gradually added dropwise over 30 minutes. Thereafter, stirring was continued for 4 hours while maintaining the temperature of the solution at 40 ° C.
[0070]
Thereafter, palladium-carbon was removed by filtration, and the mixture was poured into 1 L of water to obtain a pale yellow precipitate. This was collected by filtration, further washed with water and methanol, and dried in a vacuum dryer at 80 ° C. for 48 hours to obtain HFHA.
[0071]
Example 1
Under a stream of dry nitrogen, 19.0 g (0.095 mol) of 4,4′-diaminodiphenyl ether (manufactured by Wakayama Seika Co., Ltd.) and 1,3-bis (3-aminopropyl) tetramethyldisiloxane (Shin-Etsu Chemical ( 1.24 g (0.005 mol) of APDS (manufactured by Mitsubishi Chemical Corporation) was dissolved at 40 ° C. in 50 g of N-methyl-2-pyrrolidone (NMP manufactured by Mitsubishi Chemical Corporation). To this, 71.4 g (0.1 mol) of TMDA synthesized in Synthesis Example 1 was added at a time. After continuing stirring at 40 ° C. for 2 hours, a solution prepared by diluting 11.9 g (0.1 mol) of dimethylformamide dimethyl acetal (manufactured by Mitsubishi Rayon Co., Ltd., DMA) with 30 mL of NMP was added dropwise over 10 minutes.
[0072]
After completion of the dropwise addition, stirring was continued at 40 ° C. for 2 hours, and then 10 mL of acetic acid was added to decompose excess DMA. Thereafter, the mixture was poured into 1 L of water to obtain a white precipitate. The precipitate was collected by filtration and then washed twice with water. The precipitate after washing was dried with a vacuum dryer at 50 ° C. for 72 hours to obtain Polymer 1. 10 g of this polymer 1 was weighed, and 2 g of the photosensitizer synthesized in Synthesis Example 1 and 1 g of 1,1,2,2-tetra (4-hydroxyphenyl) ethane were added to 20 g of gamma-butyrolactone (manufactured by Mitsubishi Chemical Corporation, GBL). Dissolved. After dissolution, the solution was filtered through a 1 μm membrane filter.
[0073]
This solution was spin-coated on the bump-formed wafer using an SCW-636 coater manufactured by Dainippon Screen Mfg. Co., Ltd. so that the film thickness after hot plate treatment at 120 ° C. for 3 minutes was 12 μm. After the spin coating, a hot plate treatment at 120 ° C. × 3 minutes was performed using a SCW-636 hot plate.
[0074]
Using a contact aligner PLA-501A manufactured by Canon Inc., the wafer was mixed with ultraviolet rays of 365 nm, 405 nm, and 436 nm to measure 30 mJ / cm at 365 nm. ² Exposure was performed uniformly over the entire surface.
[0075]
This wafer was placed in a 2.38% aqueous solution of tetramethylammonium hydroxide at 23 ° C. and etched for 1 minute. After that, it was rinsed with water, and then heated at 170 ° C. for 30 minutes in an inert oven INH-21CD manufactured by Koyo Thermo System which flowed nitrogen at a flow rate of 50 L / min, then heated at 5 ° C./min and treated at 280 ° C. for 1 hour. As a result, a polyimide film as a heat-resistant resin was obtained on the wafer. The carbon concentration on the surface of the bump thus formed was 30 atomic%, and the oxygen concentration was 31 atomic%. Its thermal decomposition temperature was 530 ° C.
[0076]
Example 2
Under dry nitrogen flow, 27.2 g (0.045 mol) of HFHA synthesized in Synthesis Example 4 and 1.24 g (0.005 mol) of APDS were dissolved in 50 g of NMP at 40 ° C. Here, 15.1 g of 3,3 ', 4,4'-diphenylethertetracarboxylic dianhydride (manufactured by Manac Co., 0.05 mol) synthesized in Synthesis Example 2 was added all at once. After continuing stirring at 40 ° C. for 2 hours, a solution obtained by diluting 11.9 g (0.1 mol) of dimethylformamide dimethyl acetal DMA with 30 mL of NMP was added dropwise over 10 minutes.
[0077]
After completion of the dropwise addition, stirring was continued at 40 ° C. for 2 hours, and then 10 mL of acetic acid was added to decompose excess DMA. Thereafter, the mixture was poured into 1 L of water to obtain a white precipitate. The precipitate was collected by filtration and then washed twice with water. The precipitate after washing was dried with a vacuum dryer at 50 ° C. for 72 hours to obtain Polymer 2. 10 g of this polymer 2 was weighed, and 2 g of the photosensitizer synthesized in Synthesis Example 1 and 1 g of 1,1,2,2-tetra (4-hydroxyphenyl) ethane were dissolved in 20 g of GBL. After dissolution, the solution was filtered through a 1 μm membrane filter.
[0078]
This solution was spin-coated on the bump-formed wafer using an SCW-636 coater manufactured by Dainippon Screen Mfg. Co., Ltd. so that the film thickness after hot plate treatment at 120 ° C. for 3 minutes was 12 μm. After the spin coating, a hot plate treatment at 120 ° C. × 3 minutes was performed using a SCW-636 hot plate.
[0079]
Using a contact aligner PLA-501A manufactured by Canon Inc., the wafer was mixed with ultraviolet rays of 365 nm, 405 nm, and 436 nm to measure 30 mJ / cm at 365 nm. ² Exposure was performed uniformly over the entire surface.
[0080]
This wafer was placed in a 2.38% aqueous solution of tetramethylammonium hydroxide at 23 ° C. and etched for 1 minute. After that, it was rinsed with water, and then heated at 170 ° C. for 30 minutes in an inert oven INH-21CD manufactured by Koyo Thermo System which flowed nitrogen at a flow rate of 50 L / min, then heated at 5 ° C./min and treated at 280 ° C. for 1 hour. As a result, a polyimide film as a heat-resistant resin was obtained on the wafer. The carbon concentration on the surface of the bump thus formed was 30 atomic%, and the oxygen concentration was 31 atomic%. Its thermal decomposition temperature was 520 ° C.
[0081]
Example 3
27.0 g of 1-hydroxybenzotriazole (HBT, 0.2 mol, manufactured by Kurokin Kasei Co., Ltd.) and 20.2 g of triethylamine (0.2 mol, manufactured by Tokyo Kasei Co., Ltd.) in 200 g of NMP under a stream of dry nitrogen. Dissolve and cool to 3 ° C. To this solution, a solution prepared by dissolving 29.5 g of 4,4′-diphenyl ether dicarboxylic acid dichloride (DEDC, manufactured by Nippon Agrochemicals Co., Ltd., 0.1 mol) in 100 g of acetone was added dropwise so that the internal temperature did not exceed 10 ° C. did. The solution was stirred at 3 ° C. for 2 hours, then raised to room temperature and continued stirring for 30 minutes. After the completion of stirring, the solution was filtered to remove triethylamine hydrochloride by-produced by reaction, and the filtrate was concentrated by removing acetone with an evaporator. This concentrated solution was poured into 1 L of water to obtain a white precipitate. The precipitate was collected by filtration, washed twice with water and methanol, and dried with a 50 ° C vacuum drier for 24 hours to obtain an HBT ester of DEDC.
[0082]
Under a dry nitrogen stream, 18.3 g (0.05 mol) of BAHF and 23.6 g (0.05 mol) of the HBT ester of DEDC were dissolved in 150 g of NMP and 10 g of pyridine, and stirring was continued at 70 ° C. for 6 hours. After completion of the stirring, the solution was returned to room temperature and poured into 3 L of water to obtain a white precipitate. The precipitate was washed with 3 L of water and dried with a vacuum dryer at 50 degrees for 48 hours to obtain a polymer powder of polyhydroxyamide (polybenzoxazole precursor).
[0083]
10 g of this polyhydroxyamide, 2 g of the photosensitizer synthesized in Synthesis Example 1, and 1 g of 1,1,2,2-tetra (4-hydroxyphenyl) ethane were dissolved in 20 g of GBL. After dissolution, the solution was filtered through a 1 μm membrane filter.
[0084]
This solution was spin-coated on the bump-formed wafer using an SCW-636 coater manufactured by Dainippon Screen Mfg. Co., Ltd. so that the film thickness after hot plate treatment at 120 ° C. for 3 minutes was 12 μm. After the spin coating, a hot plate treatment at 120 ° C. × 3 minutes was performed using a SCW-636 hot plate.
[0085]
Using a contact aligner PLA-501A manufactured by Canon Inc., the wafer was mixed with ultraviolet rays of 365 nm, 405 nm, and 436 nm to measure 30 mJ / cm at 365 nm. ² Exposure was performed uniformly over the entire surface.
[0086]
This wafer was placed in a 2.38% aqueous solution of tetramethylammonium hydroxide at 23 ° C. and etched for 45 seconds. After that, it is rinsed with water, and is heated at 170 ° C. for 30 minutes in an inert oven INH-21CD manufactured by Koyo Thermo System where nitrogen flows at a flow rate of 50 L / min, then heated at 5 ° C./min and treated at 320 ° C. for 1 hour. As a result, a polybenzoxazole film as a heat-resistant resin was obtained on the wafer.
[0087]
Thereafter, using a plasma reactor PR-500 manufactured by Yamato Scientific Co., Ltd., oxygen plasma treatment was performed at a pressure of 1 torr, an oxygen flow rate of 5 sccm, and a high frequency output of 300 W for 5 minutes. The carbon concentration on the bump surface was 20 atomic%, and the oxygen concentration was 35 atomic%. Its thermal decomposition temperature was 480 ° C.
[0088]
Example 4
Under a stream of dry nitrogen, 10.7 g of 3,3 ′, 4,4′-tetraaminobenzidine (0.05 mol, manufactured by Tokyo Chemical Industry Co., Ltd.), 23.6 g of the HBT ester of DEDC obtained in Example 3 ( (0.05 mol) was dissolved in 200 g of NMP and 10 g of pyridine, and stirring was continued at 70 ° C. for 6 hours. Thereafter, the temperature of the solution was raised to 40 ° C., 8.8 g of N-acetylimidazole (manufactured by Tokyo Chemical Industry Co., Ltd., 0.08 mol) was added, and stirring was continued at 40 ° C. for 4 hours. The solution was returned to room temperature and poured into 3 L of water to obtain a white precipitate. The precipitate was washed with 3 L of water and dried in a vacuum dryer at 50 degrees for 48 hours to obtain a partially acetylated polymer powder of polyaminoamide (polybenzimidazole precursor).
[0089]
10 g of this polyaminoamide and 0.5 g of ANC-01 (manufactured by Midori Kagaku) as a photobase generator were dissolved in 30 g of NMP. After dissolution, the solution was filtered through a 1 μm membrane filter.
[0090]
This solution was spin-coated on a bump-formed wafer using a SCW-636 coater manufactured by Dainippon Screen Mfg. Co., Ltd. so that the film thickness after hot plate treatment at 100 ° C. for 4 minutes was 12 μm. After the spin coating, a hot plate treatment at 100 ° C. for 4 minutes was performed using a SCW-636 hot plate.
[0091]
Using a contact aligner PLA-501A manufactured by Canon Co., Ltd., the wafer was mixed with ultraviolet rays of 365 nm, 405 nm, and 436 nm to measure 2 J / cm at 365 nm. ² Exposure was performed uniformly over the entire surface. After the exposure, heating was performed again on a hot plate at 100 ° C. × 1 minute.
[0092]
The wafer was placed in a 1% hydrochloric acid aqueous solution at 23 ° C. and etched for 90 seconds. After that, it was rinsed with water, and then heated at 170 ° C. for 30 minutes in an inert oven INH-21CD manufactured by Koyo Thermo System which flowed nitrogen at a flow rate of 50 L / min, then heated at 5 ° C./min and treated at 280 ° C. for 1 hour. As a result, a polybenzimidazole film as a heat-resistant resin was obtained on the wafer.
[0093]
Thereafter, using a plasma reactor PR-500 manufactured by Yamato Scientific Co., Ltd., oxygen plasma treatment was performed at a pressure of 1 torr, an oxygen flow rate of 5 sccm, and a high frequency output of 300 W for 5 minutes. The carbon concentration on the bump surface was 22 atomic%, and the oxygen concentration was 35 atomic%. Its thermal decomposition temperature was 530 ° C.
[0094]
Example 5
10 g of polyetherimide (Ultem-1000, manufactured by GE Plastics Japan), 2 g of the photosensitizer synthesized in Synthesis Example 1, 1,1,2,2-tetra (4-hydroxyphenyl) ethane under a stream of dry nitrogen 1 g was dissolved in 30 g of NMP. After dissolution, the solution was filtered through a 1 μm membrane filter.
[0095]
This solution was spin-coated on the bump-formed wafer using a SCW-636 coater manufactured by Dainippon Screen Mfg. Co., Ltd. so that the film thickness after hot plate treatment at 100 ° C. for 3 minutes was 12 μm. After the spin coating, a hot plate treatment at 100 ° C. for 3 minutes was performed using a SCW-636 hot plate.
[0096]
Using a contact aligner PLA-501A manufactured by Canon Inc., the wafer was mixed with ultraviolet rays of 365 nm, 405 nm, and 436 nm to measure 1 J / cm at 365 nm. ² Exposure was performed uniformly over the entire surface. After the exposure, heating was performed again on a hot plate at 100 ° C. × 1 minute.
[0097]
This wafer was placed in a developing solution obtained by mixing 20% of NMP in a 5% aqueous solution of tetramethylammonium hydroxide at 23 ° C., and was etched for 120 seconds. Thereafter, the substrate was rinsed with water and treated at 170 ° C. for 30 minutes in an inert oven INH-21CD manufactured by Koyo Thermo System, which had flowed nitrogen at a flow rate of 50 L / min, and then heated at 5 ° C./min and treated at 250 ° C. for 1 hour.
[0098]
Thereafter, using a plasma reactor PR-500 manufactured by Yamato Scientific Co., Ltd., oxygen plasma treatment was performed at a pressure of 1 torr, an oxygen flow rate of 5 sccm, and a high frequency output of 300 W for 5 minutes. The carbon concentration on the bump surface was 30 atomic%, and the oxygen concentration was 20 atomic%. Its thermal decomposition temperature was 460 ° C.
[0099]
Example 6
Under a stream of dry air, 15.5 g of 3,3 ′, 4,4′-diphenylethertetracarboxylic dianhydride (manac Co., Ltd., 0.05 mol), 13.8 g of 3-hydroxyphenylethanol (Tokyo Kasei ( (0.1 mol), 200 ml of gamma-butyrolactone and 7.9 g of pyridine (0.1 mol, produced by Tokyo Chemical Industry Co., Ltd.) were added, and stirring was continued at 50 ° C. for 6 hours. Thereafter, the solution was cooled to −10 ° C., and a solution prepared by dissolving 20.6 g of dicyclohexylcarbodiimide (0.1 mol, manufactured by Tokyo Chemical Industry Co., Ltd.) in 200 ml of gamma-butyrolactone so that the internal temperature did not exceed 0 ° C. I dripped. After completion of the dropwise addition, stirring was continued at −10 ° C. for 30 minutes, and then the temperature was gradually increased to 20 ° C. At 20 ° C., 5.1 g of 4,4′-diaminodiphenyl ether (0.04 mol, manufactured by Wakayama Seika Co., Ltd.) and 3,5-diaminobenzoic acid (0.01 mol, manufactured by Tokyo Kasei Co., Ltd.) were added. Was. The stirring was continued at 20 ° C. for 2 hours and then at 40 ° C. for 2 hours. After completion of the stirring, the mixture was filtered to remove by-products generated by the reaction, and the solution was poured into 10 L of water to obtain a white precipitate. This precipitate was collected by filtration and washed with 5 L of water. The white precipitate was dried with a vacuum dryer at 50 ° C. for 48 hours to obtain a polyamic acid ester powder.
[0100]
10 g of a polyamic acid ester, 12 g of the photosensitive agent synthesized in Synthesis Example 1, and 0.1 g of diphenyliodotriflate (manufactured by Midori Kagaku Co., Ltd.) were dissolved in 20 g of NMP. This solution was filtered with a 1 μm membrane filter.
[0101]
This solution was spin-coated on the bump-formed wafer using a SCW-636 coater manufactured by Dainippon Screen Mfg. Co., Ltd. so that the film thickness after baking at 110 ° C. for 3 minutes was 10 μm. After spin coating, a hot plate treatment at 110 ° C. for 3 minutes was performed using a SCW-636 hot plate.
[0102]
Using a contact aligner PLA-501A manufactured by Canon Inc., in a state where ultraviolet rays of 365 nm, 405 nm, and 436 nm are mixed, 100 mJ / cm is measured at 365 nm. ² Was exposed. After the completion of the exposure, the wafer was immersed in a 2.38% aqueous solution of tetramethylammonium hydroxide for 1 minute using an SCW-636 developing device to expose the surface of the bump.
[0103]
Inert oven INH-21CD manufactured by Koyo Thermo System with nitrogen flow at a flow rate of 50 L / min. At 170 ° C. for 30 minutes, and then heated at 5 ° C./min. A polyimide film, which is a conductive resin, was obtained.
[0104]
Thereafter, using a plasma reactor PR-500 manufactured by Yamato Scientific Co., Ltd., oxygen plasma treatment was performed at a pressure of 1 torr, an oxygen flow rate of 5 sccm, and a high frequency output of 300 W for 5 minutes. The carbon concentration on the bump surface was 35 atomic%, and the oxygen concentration was 35 atomic%. Its thermal decomposition temperature was 440 ° C.
[0105]
Comparative Example 1
In a dry nitrogen stream, 19.0 g of 4,4′-diaminodiphenyl ether (0.095 mol, manufactured by Wakayama Seika Co., Ltd.), 1,3-bis (3-aminopropyl) tetramethyldisiloxane (Toray Dow Corning Silicone) 1.2 g) was dissolved at 40 ° C. in 200 g of NMP. Here, 10.9 g of pyromellitic anhydride (manufactured by Daicel Chemical Co., Ltd., 0.05 mol) and 16.1 g of 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride (manufactured by Daicel Chemical Co., Ltd.) , 0.05 mol) was added all at once with 50 ml of NMP. The mixture was stirred at 40 ° C. for 2 hours, and then was stirred at 75 ° C. for 3 hours. After the completion of the reaction, the mixture was filtered with a 1 μm membrane filter.
[0106]
This solution was spin-coated on the bump-formed wafer using a SCW-636 coater manufactured by Dainippon Screen Mfg. Co., Ltd. so that the film thickness after baking at 130 ° C. for 3 minutes was 10 μm. After the spin coating, a hot plate treatment at 130 ° C. for 3 minutes was performed using a SCW-636 hot plate. A positive photoresist OFPR-800 (manufactured by Tokyo Ohka Co., Ltd.) is placed on this wafer so that the film thickness after baking at 100 ° C. for 90 seconds becomes 2 μm, SCW-636 manufactured by Dainippon Screen Mfg. Co., Ltd. Was spin-coated using a coater. After the spin coating, a hot plate treatment at 100 ° C. × 90 seconds was performed using a SCW-636 hot plate.
[0107]
Using a contact aligner PLA-501A manufactured by Canon Inc., 200 mJ / cm was measured at 365 nm in a state where ultraviolet rays of 365 nm, 405 nm, and 436 nm were mixed. ² Exposure was performed through a mask capable of irradiating only the bump and its surrounding portion of 10 μm with ultraviolet rays. Thus, only the bump and its surroundings of 10 μm are exposed. After the exposure was completed, the wafer was placed in a 2.38% aqueous solution of tetramethylammonium hydroxide at 23 ° C., and was etched for 2 minutes and 30 seconds using the positive photoresist of the upper layer as a mask. After that, it is rinsed with water and treated at 170 ° C. for 30 minutes in an inert oven INH-21CD manufactured by Koyo Thermo System in which nitrogen flows at a flow rate of 50 L / min, and then heated at 5 ° C./min and treated at 350 ° C. for 1 hour. As a result, a polyimide film as a heat-resistant resin was obtained on the wafer.
[0108]
Thereafter, using a plasma reactor PR-500 manufactured by Yamato Scientific Co., Ltd., oxygen plasma treatment was performed at a pressure of 1 torr, an oxygen flow rate of 5 sccm, and a high frequency output of 300 W for 5 minutes.
[0109]
When cutting the wafer from the wafer prepared by this method onto a chip, a part of the shavings enters between the bump and the protective film of polyimide, and there is a possibility that the semiconductor chip surface may be damaged. The carbon concentration on the bump surface was 30 atomic%, but the oxygen concentration was as high as 45 atomic%. Its thermal decomposition temperature was 560 ° C.
[0110]
Comparative Example 2
A polyimide film was formed on a bump-formed wafer under the same conditions as in Comparative Example 1 except that the process was performed through a mask capable of irradiating ultraviolet rays only to the bump and its surrounding portion of 1 μm. The polyimide was partially adhered to the bumps produced by this method, and could not be evaluated.
[0111]
Comparative Example 3
Under a stream of dry air, 10.9 g of pyromellitic anhydride (manufactured by Daicel Chemical Industries, Ltd., 0.05 mol), 16.1 g of 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride (Daicel Chemical ( 27.6 g of 2-hydroxyethyl methacrylate (0.2 mol, manufactured by Tokyo Chemical Industry Co., Ltd.) and 200 ml of gamma-butyrolactone and 15.8 g of pyridine (manufactured by Tokyo Chemical Industry Co., Ltd., 0.2 mol). 2 mol) and stirring was continued at 50 ° C. for 6 hours. Thereafter, the solution was cooled to −10 ° C., and a solution in which 41.2 g of dicyclohexylcarbodiimide (manufactured by Tokyo Chemical Industry Co., Ltd., 0.2 mol) was dissolved in 200 ml of gamma-butyrolactone so that the internal temperature did not exceed 0 ° C. I dripped. After completion of the dropwise addition, stirring was continued at −10 ° C. for 30 minutes, and then the temperature was gradually increased to 20 ° C. At 20 ° C., 20.0 g of 4,4′-diaminodiphenyl ether (0.1 mol, manufactured by Wakayama Seika Co., Ltd.) was added. The stirring was continued at 20 ° C. for 2 hours and then at 40 ° C. for 2 hours. After completion of the stirring, the mixture was filtered to remove by-products generated by the reaction, and the solution was poured into 10 L of water to obtain a white precipitate. This precipitate was collected by filtration and washed with 5 L of water. The white precipitate was dried with a vacuum dryer at 50 ° C. for 48 hours to obtain a polyamic acid ester powder.
[0112]
Polyamic acid ester 10 g, N-phenylglycine 0.2 g (manufactured by Tokyo Chemical Industry Co., Ltd.), Irgacure 369 0.2 g (manufactured by Ciba Specialty Chemical Co., Ltd.), 1 g of ethylene glycol dimethacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.) ) Was dissolved in 20 g of NMP. This solution was filtered with a 1 μm membrane filter.
[0113]
This solution was spin-coated on the bump-formed wafer using a SCW-636 coater manufactured by Dainippon Screen Mfg. Co., Ltd. so that the film thickness after baking at 95 ° C. for 3 minutes was 10 μm. After the spin coating, a hot plate treatment at 95 ° C. for 3 minutes was performed using a SCW-636 hot plate.
[0114]
Using a contact aligner PLA-501A manufactured by Canon Inc., 200 mJ / cm was measured at 365 nm in a state where ultraviolet rays of 365 nm, 405 nm, and 436 nm were mixed. ² Exposure was carried out through a mask which covers only the bump and a portion of 10 μm surrounding the bump, and passes the others. As a result, only the bump and its surroundings of 10 μm are not exposed. After the completion of the exposure, the wafer was sprayed with a developer containing 60 parts of NMP, 37 parts of xylene and 3 parts of water for 60 seconds by using a SCW-636 developing device while rotating the wafer at 2,000 rotations. Thereafter, isopropyl alcohol was spray-sprayed while rotating at 2000 rotations for 10 seconds, and finally dried by rotating at 3000 rotations to form a pattern without the polyimide precursor film only on the bumps.
[0115]
Heat resistance at 170 ° C. for 30 minutes in an inert oven INH-21CD made by Koyo Thermo System which flowed nitrogen at a flow rate of 50 L / min for 30 minutes, then heated at 5 ° C./min, and treated at 380 ° C. for 1 hour to provide heat resistance on the wafer. A polyimide film as a resin was obtained.
[0116]
When cutting the wafer from the wafer prepared by this method onto a chip, a part of the shavings enters between the bump and the protective film of polyimide, and there is a possibility that the semiconductor chip surface may be damaged. The carbon concentration on this bump surface was very high, 45 atomic%, and the oxygen concentration was 50 atomic%. Its thermal decomposition temperature was 520 ° C.
[0117]
Comparative Example 4
Under a dry nitrogen stream, 24.2 g of 4,4'-diaminodiphenyl ether (0.12 mol, manufactured by Wakayama Seika Co., Ltd.) was dissolved in 150 g of NMP at 40 ° C. To this, 26.4 g of pyromellitic anhydride (0.12 mol, manufactured by Daicel Chemical Industries, Ltd.) was added. After stirring at 40 ° C. for 2 hours, 50 ml of toluene (manufactured by Wako Pure Chemical Industries, Ltd.) was added, and stirring was continued at 150 ° C. for 4 hours while removing water and toluene coming out of the system by azeotropic distillation. . After completion of the reaction, the solution was cooled to 30 ° C. or lower while stirring. 19.0 g of 4,4′-diaminodiphenyl ether (0.095 mol, manufactured by Wakayama Seika Co., Ltd.), 1,3-bis (3-aminopropyl) tetramethyldisiloxane (manufactured by Toray Dow Corning Silicone Co., Ltd.) Then, 31.0 g of 3,3 ′, 4,4′-diphenylethertetracarboxylic dianhydride (manufactured by 0.1 mol) was added together with 20 ml of NMP. And stirred at 50 ° C. for 4 hours.
[0118]
This solution was applied to the bump-formed wafer using a screen printer, using a stainless steel screen that was not applied to the bump portion and the surrounding 10 μm portion, so that the film thickness after curing became 20 μm. Applied.
[0119]
The wafer was treated at 80 ° C. for 60 minutes in an inert oven INH-21CD manufactured by Koyo Thermo System with nitrogen flow at a flow rate of 50 L / min, then heated at 5 ° C./min, and treated at 350 ° C. for 1 hour. A polyimide film as a heat-resistant resin was obtained.
[0120]
Thereafter, using a plasma reactor PR-500 manufactured by Yamato Scientific Co., Ltd., oxygen plasma treatment was performed at a pressure of 1 torr, an oxygen flow rate of 5 sccm, and a high frequency output of 300 W for 5 minutes.
[0121]
When cutting the wafer from the wafer prepared by this method onto a chip, a part of the shavings enters between the bump and the protective film of polyimide, and there is a possibility that the semiconductor chip surface may be damaged. In addition, the accuracy of screen printing was not sufficient, and some bumps could not be measured for electrical resistance because polyimide adhered to the surfaces of some of the bumps. The carbon concentration on the surface of the bumps varied widely from 20 to 40 atomic% and the oxygen concentration from 30 to 45 atomic%, and the oxygen content was generally large. Its thermal decomposition temperature was 540 ° C.
[0122]
Comparative Example 5
10 g of Cyclomer PCA200 (manufactured by Daicel Chemical Industries, Ltd.), which is an acrylic resin having a carboxyl group and an unsaturated group, 3 g of the photosensitive agent synthesized in Synthesis Example 1, 1,1,2,2-tetra (4-hydroxy 1 g of phenyl) ethane and 1 g of hexamethoxymethyl melamine (Cymel 300, manufactured by Mitsui Cytec Co., Ltd.) as a crosslinking agent were dissolved in 10 g of gamma-butyrolactone (GBL) and 10 g of propylene glycol monomethyl ether acetate. After dissolution, the solution was filtered through a 1 μm membrane filter.
[0123]
This solution was spin-coated on the bump-formed wafer using a SCW-636 coater manufactured by Dainippon Screen Mfg. Co., Ltd. so that the film thickness after baking at 95 ° C. for 3 minutes was 10 μm. After the spin coating, a hot plate treatment at 95 ° C. for 3 minutes was performed using a SCW-636 hot plate.
[0124]
Using a contact aligner PLA-501A manufactured by Canon Inc., in a state where ultraviolet rays of 365 nm, 405 nm and 436 nm are mixed, 50 mJ / cm is measured at 365 nm. ² Was exposed. After the exposure, the bump surface was exposed by immersing in a 0.5% aqueous solution of tetramethylammonium hydroxide at 23 ° C. for 1 minute.
[0125]
By treating at 200 ° C. for 30 minutes in an inert oven INH-21CD manufactured by Koyo Thermo System in which nitrogen flowed at a flow rate of 50 L / min, an acrylic resin film crosslinked on the wafer and having improved heat resistance was obtained.
[0126]
The carbon concentration on this bump surface was very large, 50 atomic%, and the oxygen concentration was 40 atomic%. Its thermal decomposition temperature was as low as 280 ° C.
[0127]
【The invention's effect】
According to the present invention, a highly reliable semiconductor device can be provided.

Claims (3)

A method for manufacturing a semiconductor device having a convex electrode for external connection, and having a protective film mainly composed of a heat-resistant resin having a thermal decomposition temperature of 300 ° C. or more, wherein the semiconductor element after the convex electrode is formed A method of manufacturing a semiconductor device in which a positive photosensitive heat-resistant resin composition or a precursor composition thereof is applied, the whole surface is exposed, and then developed until the surface of the convex electrode appears, and then cured. A semiconductor device having an electrode for external connection and a protective film, wherein there is no gap between the electrode exposed from the protective film and the protective film, and the oxygen concentration of the electrode surface by the XPS method is 40 atoms. % Of semiconductor devices. The semiconductor device according to claim 2, wherein the protective film is a protective film obtained by curing a heat-resistant resin composition having positive photosensitivity or a precursor composition thereof.