JP3986025B2 - Epoxy resin composition and semiconductor sealing material - Google Patents

Description

【００１３】
ここで、Ｒ_１及びＲ_２は独立的に、アルキル基或いは水素原子であり、ｎは繰り返し単位を示す０〜１０の整数である。また、この一般式において、芳香環上の置換位置のパラ位とオルト位との比率が、Ｃ^１３−ＮＭＲの測定によるパラ位／オルト位の値で０．５〜１である。このような値をとることにより、低吸湿性並びに耐熱性に優れるという顕著な効果を奏すると共に、かつ、その製造も容易になる。
【００１４】
本発明におけるＣ¹³−ＮＭＲの測定によるパラ位／オルト位の値とは、特にその測定条件が特定されるものではないが、例えば溶剤として、ＣＤＣｌ₃を用い、共鳴周波数４００ＭＨｚで測定した場合の、化学シフト１３７〜１４０ＰＰＭの面積強度を化学シフト１３０〜１３３ＰＰＭの面積強度で割った値である。
【００１５】
また、本発明で用いるエポキシ樹脂（Ａ）は、１５０℃での溶融粘度が１．０ポイズ以下である。このようなエポキシ樹脂は、高温域の弾性率が低く、さらには溶融粘度が低く流動性に優れるため、無機フィラーの高充填率化も果たせ、硬化物のクラック防止効果に著しく優れたものとなる。
【００１６】
以上、詳述したエポキシ樹脂（Ａ）を得る方法としては特に限定されるものではなく、上述したフェノール類とジシクロペンタジエンとの重付加反応させ中間体であるフェノール樹脂を製造した後、エピハロヒドヒンを反応させても良いし、また、フェノール類とジシクロペンタジエンとエピハロヒドリンを一度に反応させても良い。なかでも、得られるエポキシ樹脂（Ａ）の溶融粘度をより低く調整できる点から前者の重付加反応して重付加体であるフェノール樹脂を一旦製造した後、エピハロヒドリンを反応させる方法が好ましい。
【００１８】
本発明で用いるジシクロペンタジエンは石油留分中に含まれることから、工業用ジシクロペンタジエンには他の脂肪族或いは芳香族性ジエン類等が不純物として含有されることがあるが、耐熱性、硬化性、成形性等を考慮すると、ジシクロペンタジエンの純度９０重量％以上の製品を用いることが望ましい。
【００１９】
また、前記したフェノール類とジシクロペンタジエンとを重付加反応して重付加体であるフェノール樹脂を一旦製造した後、エピハロヒドリンを反応させる方法において、重付加物の製造条件は特に特定されるものではないが、不飽和脂環式化合物とフェノール類とを酸性触媒の存在下、加熱条件下に重付加反応させることにより製造する方法が挙げられる。なかでも８０℃以上の高温条件下、好ましくは８０〜１５０℃の高温条件下に反応させることがパラ位の比率をより高めることができる点から好ましい。
【００２０】
さらに上記重付加物の製造法を詳述すれば、溶融或いは溶剤を加えて溶液にしたフェノール類に、重付加触媒を添加し、これにジシクロペンタジエンを適下後、８０℃以上、好ましくは８０〜１５０℃に加熱攪拌し重付加反応を進行させ、反応後塩基性物質で触媒を失活し、その後に過剰のフェノール類を蒸留回収し、重付加反応物を得る。ここで重付加触媒としては、塩酸、硫酸などの無機酸或いはパラトルエンスルホン酸等の有機酸或いはＡｌＣｌ3、ＢＦ3等のルイス酸、酸性あるいは強酸性イオン交換樹脂等が挙げられる。この様にして得られる重付加物は通常、パラ置換位の割合が３０％以上で、また、その軟化点が８０〜１１５℃程度のものになる。
【００２１】
反応時のフェノール類とジシクロペンタジエンのモル比率は特に制限されるものではなくフェノール類／不飽和脂環式化合物＝１／１以上（モル比率）の条件で製造することができるが、５／１〜１０／１（モル比率）の範囲内で製造すると軟化点が８５〜１１５℃程度の中間体となり、エポキシ樹脂（Ａ）のジシクロペンタジエンが重付加反応しているフェノール類の置換位置の内パラ位とオルト位との比率が所定の範囲となって、かつ、溶融粘度を低く、耐ハンダクラック性優れる硬化物が得られる点から好ましい。
【００２２】
次いで、この様にして得られた重付加物とエピハロヒドリンとを反応させることによって、目的とするエポキシ樹脂（Ａ）とすることができるが、この反応は公知の方法に従って良く、例えば次の反応が挙げられる。
【００２３】
先ず、重付加物中の水酸基に対して０．５〜１５当量、中でもの溶融粘度の低減効果に優れる点から好ましくは３〜１０当量のエピハロヒドリンを添加して溶解し、その後、重付加反応物中の水酸基に対して０．８〜１．２当量の１０〜５０％ＮａＯＨ水溶液を５０〜８０℃の温度で３〜５時間要して適下する。適下後その温度で０．５〜２時間程度攪拌を続けて、静置後下層の食塩水を棄却する。次いで過剰のエピハロヒドリンを蒸留回収し粗樹脂を得る。これにトルエン、ＭＩＢＫ等の有機溶媒を加え、水洗−脱水−濾過−脱溶媒工程を経て、目的の樹脂を得ることができる。また不純物塩素量の低減等を目的に、反応の際ジオキサン、ＤＭＳＯ等の溶媒を併用しても良い。
【００２４】
ここで用いるエピハロヒドリンとしては、エピクロルヒドリンが最も一般的であるが、他にエピヨードヒドリン、エピブロムヒドリン、β−メチルエピクロルヒドリン等も用いることができる。
【００２５】
この様にして得られたエポキシ樹脂（Ａ）は、前述の通りＣ¹³−ＮＭＲの測定によるパラ位／オルト位の値で０．５以上であり、また、その溶融粘度は、通常、１５０℃での溶融粘度が０．１〜１０ポイズのものとなるが、既述の通り１．０ポイズ以下であることが好ましいが、上記製造方法における重付加体の内、適当な融点の中間体のを選ぶことにより、１．０ポイズ以下のものを容易に製造することができる。
【００２６】
また、本発明に用いられる硬化剤（Ｂ）としては、通常エポキシ樹脂の硬化剤として常用されている化合物はすべて使用することができ、特に限定されるものではないが、例えばジエチレントリアミン、トリエチレンテトラミンなどの脂肪族アミン類、メタフェニレンジアミン、ジアミノジフェニルメタン、ジアミノジフェニルスルホンなどの芳香族アミン類；フェノールノボラック樹脂、オルソクレゾールノボラック樹脂、アルキルフェノールノボラック樹脂、ビスフェノールＡノボラック樹脂、ビスフェノールＦノボラック樹脂、ナフトールノボラック樹脂、ジヒドロキシナフタレンノボラック樹脂等のノボラック樹脂；フェノール類−ジシクロペンタジエン付加型樹脂、アルキルフェノール類−ジシクロペンタジエン付加型樹脂、ナフトール類−ジシクロペンタジエン付加型樹脂、キシリデンを結接基とするポリフェノール類等の多価フェノール類；アルキルフェノール類；ナフトール類樹脂；ポリアミド樹脂およびそれらの変性物；無水マレイン酸、無水フタル酸、無水ヘキサヒドロフタル酸、無水ピロメリット酸などの酸無水物系硬化剤；ジシアンジアミド、イミダゾール、ＢＦ3 −アミン錯体、グアニジン誘導体等の潜在性硬化剤等が挙げられる。中でも半導体封止材用としては、上記ノボラック樹脂、特にフェノールノボラック樹脂が硬化物の耐熱性や耐水性に優れる点から好ましい。
【００２７】
これらの硬化剤の使用量は、エポキシ樹脂を硬化せしめる量であれば何れでもよく、特に限定されないが、好ましくは用いるエポキシ樹脂の一分子中に含まれるエポキシ基の数と、硬化剤中の活性水素の数が当量付近となる量である。
【００２８】
上掲された如き各化合物を硬化剤として用いる際は、硬化促進剤を適宜使用することができる。
【００２９】
硬化促進剤としては公知慣用のものがいずれも使用できるが、例えば、第３級アミン、イミダゾール、有機酸金属塩、ルイス酸、アミン錯塩、トリフェニルホスフィン等のリン系化合物等が挙げられ、これらは単独のみならず２種以上の併用も可能である。
【００３０】
本発明のエポシキ樹脂組成物は、上述したエポキシ樹脂（Ａ）および硬化剤（Ｂ）を必須の成分とするものであるが、更に無機フィラー（Ｃ）を併用することにより、更に硬化物の機械強度、硬度を高めることができ好ましい。特に本発明の半導体封止材料としては、無機フィラーは必須の構成成分であり、機械的強度、硬度を高められるだけでなく、低吸水率、低線膨張係数を達成し、クラック防止効果を高めることができる。
【００３１】
その配合量は、特に限定されるものではないが、組成物中７５〜９５重量％の範囲で用いることが、特にそれらの特性が際立つものとなり、特に半導体封止剤用途において耐ハンダクラック性が非常に良好となる点から好ましい。
【００３２】
また、ここで特筆すべき点は、本発明において７３重量％以上無機フィラーを添加しても流動性、成形性を全く損なうことがないことである。。
【００３３】
この様な無機フィラー（Ｃ）としては、特に限定されないが溶融シリカ、結晶シリカ、球状シリカ、粉砕シリカ、アルミナ、タルク、クレー、ガラス繊維等が挙げられる。これらの中でも、特に半導体封止材料用途においては溶融シリカ、結晶シリカが一般的に用いられており、特に流動性に優れる点から溶融シリカが好ましい。
【００３４】
また本発明のエポキシ樹脂組成物は、必須成分である上述したエポキシ樹脂（Ａ）に加え、さらにその他のエポキシ樹脂を併用しても構わない。
この際に用いられるエポキシ樹脂としては、公知慣用のものが何れも使用でき、例えばビスフェノールＡジグリシジルエーテル型エポキシ樹脂、フェノールノボラック型エポキシ樹脂、オルソクレゾールノボラック型エポキシ樹脂、ビスフェノールＡノボラック型エポキシ樹脂、ビスフェノールＦノボラック型エポキシ樹脂、臭素化フェノールノボラック型エポキシ樹脂、ナフトールノボラック型エポキシ樹脂、ビフェニル型２官能エポキシ樹脂、ヒドロキシベンツアルデヒドとフェノール類との縮合物のポリグリシジルエーテル等が挙げられるが、これらに限定されるものではない。これらの中でも、特に耐熱性に優れる点からオルソクレゾールノボラック型エポキシ樹脂が、また流動性に優れる点からビフェニル型２官能エポキシ樹脂が好ましい。
【００３５】
また必要に応じて、着色剤、難燃剤、離型剤、またはカップリング剤などの公知慣用の各種の添加剤成分も適宜配合せしめることができる。
また、本発明のエポキシ樹脂組成物から成型材料を調製するには、エポキシ樹脂、硬化剤、硬化促進剤、その他の添加剤をミキサー等によって十分に均一に混合した後、更に熱ロールまたはニーダ−等で溶融混練し、冷却後粉砕することにより得ることができ、また、粉砕された粉末を成型しタブレット状にして実用に供することもできる。
【００３６】
この様にして得られる本発明のエポキシ樹脂組成物は、特にその用途が限定されるものではなく、例えば、半導体封止材料や、エポキシ樹脂の溶剤溶解性に優れるために電気積層板用途でのワニス等が挙げられる。また、本発明のエポキシ樹脂を臭素化多価フェノール類で変性を施したオリゴマー型エポキシ樹脂を積層板用途に用いることもできる。さらにはエポキシ樹脂（Ａ）と併用し得るその他のエポキシ樹脂成分として多官能型エポキシ樹脂を配合或いは変性し耐熱性を付与させたシステムも使用できる。
【００３７】
また高分子タイプエポキシ樹脂を得るために、２段法反応の原料樹脂として当該樹脂を使用することも可能である。
これらの用途の中でも、特に耐ハンダクラック性に著しく優れる等の利点から半導体封止材料用途が極めて有用である。
【００３８】
また、本発明の半導体封止材料としては、上述した（Ａ）〜（Ｃ）の各成分の他にテテラブロモＡ型エポキシ樹脂、ブロム化フェノールノボラック型エポキシ樹脂等の臭素化エポキシ樹脂、三酸化アンチモン、ヘキサブロモベンゼン等の難燃剤、カ−ボンブラック、ベンガラ等の着色剤、天然ワックス、合成ワックス等の離型剤及びシリコンオイル、合成ゴム、シリコーンゴム等の低応力添加剤等の添加剤を適宜配合することが好ましい。
【００３９】
本発明の半導体封止材料を用いて成型材料を調製するには、上記各成分をミキサー等によって十分に均一に混合した後、更に熱ロールまたはニーダ−等で溶融混練し、射出あるいは冷却後粉砕するなどして得ることができる。
【００４０】
【実施例】
次に本発明を製造例、実施例およびその比較例により具体的に説明する。尚、例中において部は特に断りのない限りすべて重量部である。
【００４１】
尚、オルト置換体とパラ置換位の割合はＣ^１３−ＮＭＲ（溶剤：ＣＤＣｌ_３、共鳴周波数４００ＭＨｚ）を用いて、ベンゼン環のグリシジルエーテル基の置換位を基準にジシクロペンタジエンが付加したベンゼン環のパラ位とオルト位との炭素の量を測定し、下記の式に従って算出した。
【００４２】
【式１】

【００４３】
また、溶融粘度は５０ＨｚのもとにおいてReseach equipment ＬＴＤ．製「ＩＣＩ ＣＯＮＥ ＆ ＰＬＡＴＥ ＶＩＳＣＯＭＥＴＥＲ」で測定した。また軟化点は明峰社製作所(株)製「軟化点測定器」（加熱器：ＨＵ−ＭＫ，検出器ＡＳＰ−Ｍ２）測定した。
【００４４】
製造例１
攪拌機、温度計、４つ口フラスコにフェノール９４０ｇ（１０モル）を、９８％硫酸５．６ｇを添加し充分混合した。その後ジシクロペンタジエン１８５ｇ（１．４モル）を系内温度を９０〜１００℃に保ちながら１時間要して添加した。その後系内温度を１１０℃にし、３時間加熱攪拌し、得られた反応生成物溶液にマグネシウム化合物「KW-1000」（商品名；協和化学工業(株)社製４０ｇを添加し、３０分間攪拌して触媒を失活させた後、反応溶液を濾過した。得られた透明溶液から過剰のフェノールを蒸留回収して褐色の固形樹脂４０８ｇを得た。この樹脂の軟化点は９６℃、水酸基当量は１６９g/eqあった。
【００４５】
この樹脂３３８ｇにエピクロルヒドリン９２５ｇ（１０モル）をいれ溶解する。それに８０℃で２０％ＮａＯＨ４４０ｇ（２．２モル）を３時間かけて攪拌しながら滴下し、さらに３０分間攪拌を続けてその後静置した。下層の食塩水を棄却し、エピクロルヒドリンを１５０℃で蒸留回収した後、粗樹脂にＭＩＢＫ６００ｇを加え、さらに水２５０ｇを加え８０℃にて水洗した。そして下層の水洗水を棄却した後、脱水、濾過を経てＭＩＢＫを１５０℃で脱溶剤して目的のエポキシ樹脂（ａ）４２７ｇを得た。この樹脂は褐色固体で、軟化点６５℃、１５０℃での溶融粘度０．７ポイズ、エポキシ当量は２５８g/eqであった。また、パラ位とオルト位の比は０．７５であった。
【００４６】
製造例２
中間体を製造する際のフェノール９４０ｇ（１０モル）をフェノール４７０ｇ（５モル）に変更した以外は製造例１と同様にしてエポキシ樹脂（ｂ）４３０ｇを得た。この樹脂は褐色固体で、軟化点８０℃、１５０℃での溶融粘度３．５ポイズ、エポキシ当量は２６５g/eqであった。また、パラ位とオルト位の比は０．７５であった。
【００４７】
製造例３
中間体を製造する際のジシクロペンタジェンの添加後の系内温度を１１０℃から１２０℃に変更した以外は製造例１と同様にして、エポキシ樹脂（ｃ）４２５ｇを得た。この樹脂は褐色固体で、軟化点６５℃、１５０℃での溶融粘度０．８ポイズ、エポキシ当量は２６０g/eqであった。また、パラ位とオルト位の比は０．８２であった。
【００４８】
製造例４
中間体を製造する際のフェノール９４０ｇ（１０モル）をフェノール７５２ｇ（８モル）に、またジシクロペンタジェンの添加後の系内温度を１１０℃から１００℃に変更した以外は製造例１と同様にして、エポキシ樹脂（ｄ）４３０ｇを得た。この樹脂は褐色固体で、軟化点６７℃、１５０℃での溶融粘度０．９ポイズ、エポキシ当量は２６２g/eqであった。また、パラ位とオルト位の比は０．６１であった。
【００４９】
製造例５
中間体を製造する際のフェノール９４０ｇ（１０モル）をフェノール６５８ｇ（７モル）に、またジシクロペンタジェンの添加後の系内温度を１１０℃から９０℃に変更した以外は、製造例１と同様にしてエポキシ樹脂（ｅ）４２８ｇを得た。この樹脂は褐色固体で、軟化点６８℃、１５０℃での溶融粘度１．１ポイズ、エポキシ当量は２６２g/eqであった。また、パラ位とオルト位の比は０．５３であった。
【００５０】
製造比較例１
中間体を製造する際のジシクロペンタジェンの添加後の系内温度を１１０℃から６０℃にし、反応時間を３時間から１０時間に変更した以外は製造例１と同様にして、エポキシ樹脂（ｆ）４２５ｇを得た。この樹脂は褐色固体で、軟化点６４℃、１５０℃での溶融粘度０．７ポイズ、エポキシ当量は２６０g/eqであった。また、パラ位とオルト位の比は０．４２であった。
【００５１】
製造比較例２
中間体を製造する際のジシクロペンタジェンの添加後の系内温度を１１０℃から７０℃にし、反応時間を３時間から６時間に変更した以外は製造例１と同様にして、エポキシ樹脂（ｇ）４２５ｇを得た。この樹脂は褐色固体で、軟化点６４℃、１５０℃での溶融粘度０．７ポイズ、エポキシ当量は２６０g/eqであった。また、パラ位とオルト位の比は０．４８であった。
【００５２】
製造比較例３
中間体を製造する際のジシクロペンタジェンの添加後の系内温度を１１０℃から７０℃にし、反応時間を３時間から６時間に変更した以外は製造例４と同様にして、エポキシ樹脂（ｈ）４２５ｇを得た。この樹脂は褐色固体で、軟化点６６℃、１５０℃での溶融粘度０．９ポイズ、エポキシ当量は２６２g/eqであった。また、パラ位とオルト位の比は０．３７であった。
【００５３】
製造比較例４
中間体を製造する際のジシクロペンタジェンの添加後の系内温度を１１０℃から７０℃にし、反応時間を３時間から６時間に変更した以外は製造例２と同様にして、エポキシ樹脂（ｉ）４２５ｇを得た。この樹脂は褐色固体で、軟化点７９℃、１５０℃での溶融粘度３．４ポイズ、エポキシ当量は２６４g/eqであった。また、パラ位とオルト位の比は０．３３であった。
【００５４】
実施例１〜３及び比較例１〜６
第１表及び第２表で表される配合に従って調製した混合物を熱ロールにて１００℃・８分間混練りし、その後粉砕したものを1200-1400Kg/cm^２ の圧力にてタブレットを作製し、それを用いてトランスファー成形機にてプランジャー圧力８０Kg/cm^２、金型温度１７５℃、成形時間１００秒の条件下にて封止し、厚さ２mmのフラットパッケージを評価用試験片として作成した。その後１７５℃で８時間の後硬化を施した。尚、溶融シリカの配合量は、得られた配合物の流動性が同一になるように調整された。また、フェノールノボラック硬化剤として、フェノライトＴＤ−２１３１（大日本インキ化学工業(株)製：水酸基当量 １０７g/eq.、核体数 ５）を使用した。
【００５５】
この評価用試験片を用い、８５℃・８５％ＲＨ条件下での吸水率、ＤＭＡによるガラス転移温度および動的粘弾性率を測定した。また、試験片を８５℃・８５％ＲＨの雰囲気下中７２時間放置し、吸湿処理を行った後、これを２６０℃のハンダ浴に１０秒浸せきし、その際のクラック発生率を調べて耐ハンダクラック性を評価した。試験片数は２０個。この結果を同じく第１表及び第２表に示す。
【００５６】
【表１】

【００５７】
【表２】

【００５８】
【発明の効果】
本発明によれば、低吸湿性並びに耐熱性に優れた硬化物と成り得るエポキシ樹脂組成物、及び、低吸湿性により耐ハンダクラックの防止効果に優れる上に耐熱性にも優れる半導体封止材料を提供できる。[0001]
[Industrial application fields]
The present invention is a novel, particularly heat-resistant, water-resistant, high-temperature physical property, fluidity, moldability and low internal stress, so that it can be used for semiconductor encapsulating materials, laminated component materials, electrical insulating materials, fiber-reinforced composite materials. The present invention relates to an epoxy resin composition that is extremely useful as a coating material, a molding material, an adhesive material, and the like, and a semiconductor sealing material remarkably excellent in solder crack resistance and heat resistance.
[0002]
[Prior art]
Epoxy resins are generally cured with various curing agents, resulting in cured products with excellent mechanical properties, water resistance, chemical resistance, heat resistance, electrical properties, etc., adhesives, paints, laminates, Used in a wide range of fields such as molding materials and casting materials.
[0003]
In particular, in semiconductor encapsulating material applications, as the semiconductor mounting method has changed to the surface mounting method in recent years, it has excellent solder crack resistance, that is, cracks due to the expansion of water in the encapsulating material due to the heat of the solder. In order to prevent this, a material with low moisture absorption and high heat resistance is required. Conventionally, polyglycidyl ethers of polyaddition reactants of phenols and unsaturated alicyclic compounds have been used as epoxy resins as epoxy resin compositions satisfying such required characteristics, for example, as disclosed in JP-A-61-293219. In addition, a sealing material using a dicyclopentadiene-phenol-modified epoxy resin as described in JP-A-2006-260707 is known.
[0004]
[Problems to be solved]
However, the above epoxy resin composition has a problem that it has excellent hygroscopicity but low heat resistance, and particularly as a semiconductor sealing material, it has a problem that it is inferior in the reliability of a semiconductor chip from the point of poor heat resistance. Had.
[0005]
The problem to be solved by the present invention is an epoxy resin composition that can be a cured product excellent in low moisture absorption and heat resistance, and a semiconductor that is excellent in solder crack resistance prevention effect due to low moisture absorption and also excellent in heat resistance It is to provide a sealing material.
[0006]
[Means for Solving the Problems]
As a result of intensive studies by the inventors, as an epoxy resin, phenol, m-cresol, 3,5-xylenol, alkylphenol having an alkyl group having 2 to 6 carbon atoms at the m-position, and carbon atoms at the 3,5-position Diphenol pentadiene selected from the group consisting of dialkylphenol having 2 to 6 alkyl groups, m-chlorophenol, m-bromophenol, 3,5-dichlorophenol, and 3,5-dibromophenol It has been found that the above problems can be solved by using an epoxy resin having a specific structure obtained by reacting a polyaddition reactant with epichlorohydrin, and the present invention has been completed.
[0007]
That is, in the present invention, a divalent hydrocarbon group based on an unsaturated bond in the molecular structure of dicyclopentadiene is used as a linking group , and phenol, m-cresol, 3,5-xylenol, having 2 to 2 carbon atoms at the m-position. Alkylphenols having 6 alkyl groups, dialkylphenols having an alkyl group having 2 to 6 carbon atoms in the 3,5-position, m-chlorophenol, m-bromophenol, 3,5-dichlorophenol, and 3,5- A polyglycidyl ether of a polyadduct bonded to a phenol selected from the group consisting of dibromophenol , having a melt viscosity at 150 ° C. of 1.0 poise or less and bonded onto the aromatic ring of the phenol and the ratio of the para and ortho substitution position of the binding Semmoto by which is 0.5 at the value of para / ortho position by measuring C ¹³ -NMR Epoxy resin composition, characterized in that one of the epoxy resin (A) and curing agent (B) as essential components, and, a divalent hydrocarbon group based on unsaturated bonds in the molecular structure of dicyclopentadiene As a linking group , phenol, m-cresol, 3,5-xylenol, alkylphenol having an alkyl group having 2 to 6 carbon atoms at the m-position, and an alkyl group having 2 to 6 carbon atoms at the 3,5-position A polyglycidyl ether of a polyadduct combined with a phenol selected from the group consisting of dialkylphenol, m-chlorophenol, m-bromophenol, 3,5-dichlorophenol, and 3,5-dibromophenol , The melt viscosity at 150 ° C. is 1.0 poise or less, and the substitution position of the linking group bonded onto the aromatic ring of the phenol is Ratio of La-position and ortho ^position, C 13 -NMR para by the measuring / ortho value 0.5 of the epoxy resin (A), the essential curing agent (B) and the inorganic filler (C) The present invention relates to a semiconductor sealing material characterized in that it is a component.
[0008]
The epoxy resin (A) used in the present invention is phenol, m-cresol, 3,5-xylenol, alkylphenol having an alkyl group having 2 to 6 carbon atoms at the m-position, and 2 to 2 carbon atoms at the 3,5-position. Polyaddition of dicyclopentadiene with a phenol selected from the group consisting of dialkylphenol having 6 alkyl groups, m-chlorophenol, m-bromophenol, 3,5-dichlorophenol, and 3,5-dibromophenol In the glycidyl ether form of the reactant, the ratio of the para-position to the ortho-position of the linking group bonded to the aromatic ring of the phenols is para-position / ortho-position as measured by C ¹³ -NMR. An epoxy resin having a value of 0.5 to 1, that is, an epihalohydrin is reacted with a specific polyaddition reactant rich in para-substitution. An epoxy resin having a skeleton obtained Te.
[0009]
As phenols used for the epoxy resin (A) , phenol, m-cresol, 3,5-xylenol, alkylphenol having an alkyl group having 2 to 6 carbon atoms at the m position, and carbon atoms at the 3,5-position dialkylphenols having 2-6 alkyl groups, m- chlorophenol, m- bromophenol, a 3,5-dichlorophenol, or 3,5-dibromo phenol, property balance or distilled ease of recovery during production To phenol are preferred.
[0010]
Further, the divalent hydrocarbon group based on the unsaturated bond in the molecular skeleton of dicyclopentadiene constituting the epoxy resin (A) is bonded to the linking group of the phenol skeleton part that forms the glycidyl ether structure portion of the epoxy resin. Thus , the heat resistance and moisture resistance of the cured product can be further improved .
[0011]
More specific examples of such an epoxy resin (A) include those represented by the following general formula.
[0012]
[Chemical 1]

[0013]
Here, R ₁ and R ₂ are independently an alkyl group or hydrogen atom, n represents an integer of 0 indicating a repeating unit. Further, in this general formula, the ratio of para and ortho substitution positions on the aromatic ring is a para / 0.5-1 ortho values by the measurement of C ¹³ -NMR. By taking such a value, the remarkable effect of being excellent in low moisture absorption and heat resistance is exhibited, and the manufacture thereof is facilitated .
[0014]
The value of para / ortho position by C ¹³ -NMR measurement in the present invention is not particularly specified for the measurement conditions, but for example, when CDCl ₃ is used as a solvent and measurement is performed at a resonance frequency of 400 MHz. The value obtained by dividing the area intensity of chemical shifts 137 to 140 PPM by the area intensity of chemical shifts 130 to 133 PPM.
[0015]
The epoxy resin (A) used in the present invention has a melt viscosity at 150 ° C. of 1.0 poise or less . Such epoxy resins have a low modulus of elasticity of the high temperature region, since more excellent fluidity low melt viscosity, fulfill even higher filling ratio of inorganic fillers, it becomes significantly superior crack prevention effect of the cured product .
[0016]
Above, there is no particular limitation on the method for obtaining the detailed epoxy resin (A), after producing a phenol resin which is an intermediate to a polyaddition reaction with the above-mentioned phenols and dicyclopentadiene, the Epiharohidohin It may be reacted, or phenols, dicyclopentadiene and epihalohydrin may be reacted at once. Especially, the method of making the former polyaddition reaction and the phenol resin which is a polyadduct once manufactured from the point which can adjust the melt viscosity of the obtained epoxy resin (A) lower can react with epihalohydrin.
[0018]
Since dicyclopentadiene used in the present invention is contained in petroleum fractions, industrial dicyclopentadiene may contain other aliphatic or aromatic dienes as impurities, In consideration of curability, moldability, etc., it is desirable to use a product having a purity of 90% by weight or more of dicyclopentadiene.
[0019]
In addition, in the method in which the phenol resin and dicyclopentadiene described above are subjected to a polyaddition reaction to once produce a phenol resin which is a polyaddition product and then reacted with an epihalohydrin, the production conditions of the polyaddition product are not particularly specified. However, there is a method of producing an unsaturated alicyclic compound and a phenol by a polyaddition reaction under heating conditions in the presence of an acidic catalyst. Especially, it is preferable from the point which can raise the ratio of a para position to make it react on high temperature conditions of 80 degreeC or more, Preferably it is 80-150 degreeC high temperature conditions.
[0020]
Further, the production method of the above polyaddition product will be described in detail. A polyaddition catalyst is added to phenols which are melted or added to a solution to form a solution, and after dicyclopentadiene is appropriately added thereto, 80 ° C. or more, preferably The mixture is heated and stirred at 80 to 150 ° C. to advance the polyaddition reaction. After the reaction, the catalyst is deactivated with a basic substance, and then excess phenols are recovered by distillation to obtain a polyaddition reaction product. Examples of the polyaddition catalyst include inorganic acids such as hydrochloric acid and sulfuric acid, organic acids such as p-toluenesulfonic acid, Lewis acids such as AlCl3 and BF3, and acidic or strongly acidic ion exchange resins. The polyaddition product thus obtained usually has a para substitution ratio of 30% or more and a softening point of about 80 to 115 ° C.
[0021]
The molar ratio of phenols and dicyclopentadiene during the reaction is not particularly limited and can be produced under the conditions of phenols / unsaturated alicyclic compound = 1/1 or more (molar ratio). When it is produced within the range of 1 to 10/1 (molar ratio), it becomes an intermediate having a softening point of about 85 to 115 ° C., and the substitution position of phenols in which dicyclopentadiene of the epoxy resin (A) undergoes polyaddition reaction This is preferable in that a ratio between the inner para position and the ortho position is within a predetermined range, and a cured product having a low melt viscosity and excellent solder crack resistance is obtained.
[0022]
Next, by reacting the thus obtained polyaddition product with epihalohydrin, the desired epoxy resin (A) can be obtained. This reaction may be carried out according to a known method. Can be mentioned.
[0023]
First, 0.5 to 15 equivalents, preferably 3 to 10 equivalents of epihalohydrin are added and dissolved with respect to the hydroxyl group in the polyaddition product, and the melt viscosity is preferably reduced. 0.8 to 1.2 equivalents of a 10-50% NaOH aqueous solution with respect to the hydroxyl group in the solution is required for 3 to 5 hours at a temperature of 50 to 80 ° C. Stirring is continued for about 0.5 to 2 hours at that temperature after appropriate reduction, and the lower layer saline solution is discarded after standing. Then, excess epihalohydrin is recovered by distillation to obtain a crude resin. To this, an organic solvent such as toluene or MIBK is added, and a target resin can be obtained through a water washing-dehydration-filtration-desolvation step. For the purpose of reducing the amount of impurity chlorine, a solvent such as dioxane or DMSO may be used in the reaction.
[0024]
As the epihalohydrin used here, epichlorohydrin is the most common, but epiiodohydrin, epibromohydrin, β-methylepichlorohydrin, and the like can also be used.
[0025]
The epoxy resin (A) thus obtained has a para / ortho value of 0.5 or more as measured by C ¹³ -NMR as described above, and the melt viscosity is usually 150 ° C. The melt viscosity at 0.1 to 10 poise is preferably 1.0 poise or less as described above. Of the polyaddition products in the above production method, an intermediate having an appropriate melting point is used. By selecting, it is possible to easily manufacture the one having 1.0 poise or less.
[0026]
In addition, as the curing agent (B) used in the present invention, all compounds usually used as curing agents for epoxy resins can be used, and are not particularly limited. For example, diethylenetriamine, triethylenetetramine Aliphatic amines such as metaphenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, etc .; phenol novolac resin, orthocresol novolak resin, alkylphenol novolak resin, bisphenol A novolak resin, bisphenol F novolak resin, naphthol novolak resin , Novolak resins such as dihydroxynaphthalene novolak resins; phenols-dicyclopentadiene addition resins, alkylphenols-dicyclopentadiene addition resins, naphtha Polyols-dicyclopentadiene addition type resins, polyphenols such as polyphenols having xylidene as a linking group; alkylphenols; naphthol resins; polyamide resins and their modified products; maleic anhydride, phthalic anhydride, Acid anhydride type curing agents such as hexahydrophthalic anhydride and pyromellitic anhydride; latent curing agents such as dicyandiamide, imidazole, BF3 -amine complex, and guanidine derivatives. Among these, for semiconductor encapsulating materials, the above-mentioned novolak resins, particularly phenol novolak resins, are preferable from the viewpoint of excellent heat resistance and water resistance of the cured product.
[0027]
The amount of these curing agents used is not particularly limited as long as it cures the epoxy resin, but preferably the number of epoxy groups contained in one molecule of the epoxy resin used and the activity in the curing agent. The amount of hydrogen is about equivalent.
[0028]
When each compound as listed above is used as a curing agent, a curing accelerator can be appropriately used.
[0029]
Any known and commonly used curing accelerators can be used. Examples include tertiary amines, imidazoles, organic acid metal salts, Lewis acids, amine complex salts, phosphorus-based compounds such as triphenylphosphine, and the like. Can be used alone or in combination of two or more.
[0030]
The epoxy resin composition of the present invention comprises the above-described epoxy resin (A) and curing agent (B) as essential components, and further by using an inorganic filler (C) in combination, the cured product can be further machined. It is preferable because strength and hardness can be increased. In particular, as a semiconductor sealing material of the present invention, an inorganic filler is an essential component and not only can increase mechanical strength and hardness, but also achieve a low water absorption rate and a low linear expansion coefficient, thereby increasing the crack prevention effect. be able to.
[0031]
The blending amount is not particularly limited, but using in the range of 75 to 95% by weight in the composition makes the characteristics particularly prominent, and particularly has a solder crack resistance in semiconductor encapsulant applications. It is preferable from the point of being very good.
[0032]
In addition, the point to be noted here is that, even if an inorganic filler of 73 wt% or more is added in the present invention, fluidity and moldability are not impaired at all. .
[0033]
Examples of such inorganic filler (C) include, but are not limited to, fused silica, crystalline silica, spherical silica, pulverized silica, alumina, talc, clay, and glass fiber. Among these, fused silica and crystalline silica are generally used particularly for semiconductor sealing material applications, and fused silica is particularly preferred from the viewpoint of excellent fluidity.
[0034]
Moreover, in addition to the epoxy resin (A) which is an essential component, the epoxy resin composition of the present invention may be used in combination with other epoxy resins.
As the epoxy resin used in this case, any known and commonly used epoxy resins can be used. For example, bisphenol A diglycidyl ether type epoxy resin, phenol novolac type epoxy resin, orthocresol novolak type epoxy resin, bisphenol A novolak type epoxy resin, Bisphenol F novolak type epoxy resin, brominated phenol novolak type epoxy resin, naphthol novolak type epoxy resin, biphenyl type bifunctional epoxy resin, polyglycidyl ether of condensate of hydroxybenzaldehyde and phenols, etc. It is not limited. Among these, an ortho-cresol novolak type epoxy resin is particularly preferable from the viewpoint of excellent heat resistance, and a biphenyl type bifunctional epoxy resin is preferable from the viewpoint of excellent fluidity.
[0035]
Further, if necessary, various known and commonly used additive components such as a colorant, a flame retardant, a release agent, or a coupling agent can be appropriately blended.
Moreover, in order to prepare a molding material from the epoxy resin composition of the present invention, an epoxy resin, a curing agent, a curing accelerator, and other additives are sufficiently uniformly mixed by a mixer or the like, and then further heated roll or kneader. It can be obtained by melt-kneading with the aid of, etc., and pulverizing after cooling. Alternatively, the pulverized powder can be molded into a tablet and put to practical use.
[0036]
The epoxy resin composition of the present invention obtained in this way is not particularly limited in its use. For example, it is excellent in semiconductor sealing materials and epoxy resin solvent solubility, so that it can be used in electrical laminates. A varnish etc. are mentioned. Moreover, the oligomer type epoxy resin which modified | denatured the epoxy resin of this invention with brominated polyhydric phenols can also be used for a laminated board use. Furthermore, the system which mix | blended or modified | denatured the polyfunctional epoxy resin as another epoxy resin component which can be used together with an epoxy resin (A), and provided heat resistance can also be used.
[0037]
In order to obtain a polymer type epoxy resin, it is also possible to use the resin as a raw material resin for a two-step reaction.
Among these uses, a semiconductor encapsulating material application is extremely useful due to advantages such as remarkably excellent solder crack resistance.
[0038]
In addition to the components (A) to (C) described above, the semiconductor encapsulating material of the present invention includes brominated epoxy resins such as Teterabromo A type epoxy resin, brominated phenol novolac type epoxy resin, antimony trioxide, and the like. Additives such as flame retardants such as hexabromobenzene, colorants such as carbon black and bengara, mold release agents such as natural wax and synthetic wax, and low-stress additives such as silicone oil, synthetic rubber and silicone rubber It is preferable to mix appropriately.
[0039]
In order to prepare a molding material using the semiconductor sealing material of the present invention, the above components are sufficiently uniformly mixed with a mixer or the like, and then melt-kneaded with a hot roll or a kneader, and then injected or ground after cooling. You can get it.
[0040]
【Example】
Next, the present invention will be specifically described with reference to production examples, examples and comparative examples. In the examples, all parts are parts by weight unless otherwise specified.
[0041]
The ratio of the ortho-substituted product to the para-substituted position is C ¹³ -NMR (solvent: CDCl ₃ , resonance frequency 400 MHz), and the benzene ring to which dicyclopentadiene is added based on the substitution position of the glycidyl ether group of the benzene ring. The amount of carbon at the para and ortho positions was measured and calculated according to the following formula.
[0042]
[Formula 1]

[0043]
In addition, the melt viscosity is Reseach equipment LTD. It was measured by “ICI CONE & PLATE VISCOMTER” manufactured by the manufacturer. The softening point was measured by “Softening point measuring device” (heater: HU-MK, detector ASP-M2) manufactured by Meihosha Mfg. Co., Ltd.
[0044]
Production Example 1
To a stirrer, thermometer, and 4-neck flask, 940 g (10 mol) of phenol and 5.6 g of 98% sulfuric acid were added and mixed well. Thereafter, 185 g (1.4 mol) of dicyclopentadiene was added over 1 hour while maintaining the system temperature at 90 to 100 ° C. Thereafter, the system temperature was set to 110 ° C., and the mixture was heated and stirred for 3 hours. Magnesium compound “KW-1000” (trade name; 40 g manufactured by Kyowa Chemical Industry Co., Ltd.) was added to the obtained reaction product solution, and the mixture was stirred for 30 minutes. After the catalyst was deactivated, the reaction solution was filtered, and excess phenol was recovered by distillation from the resulting transparent solution to obtain 408 g of a brown solid resin having a softening point of 96 ° C. and a hydroxyl group equivalent. Was 169 g / eq.
[0045]
Into 338 g of this resin, 925 g (10 mol) of epichlorohydrin is added and dissolved. Then, 440 g (2.2 mol) of 20% NaOH was added dropwise at 80 ° C. over 3 hours while stirring, and the mixture was further stirred for 30 minutes and then allowed to stand. The lower layer saline was discarded, and epichlorohydrin was recovered by distillation at 150 ° C., and then 600 g of MIBK was added to the crude resin, and 250 g of water was further added, followed by washing at 80 ° C. And after discarding the lower layer washing water, MIBK was desolvated at 150 degreeC through dehydration and filtration, and 427g of the target epoxy resin (a) was obtained. This resin was a brown solid and had a softening point of 65 ° C., a melt viscosity of 0.7 poise at 150 ° C., and an epoxy equivalent of 258 g / eq. The ratio between the para position and the ortho position was 0.75.
[0046]
Production Example 2
Epoxy resin (b) 430 g was obtained in the same manner as in Production Example 1 except that phenol 940 g (10 mol) used in the production of the intermediate was changed to phenol 470 g (5 mol). This resin was a brown solid and had a softening point of 80 ° C., a melt viscosity of 3.5 poise at 150 ° C., and an epoxy equivalent of 265 g / eq. The ratio between the para position and the ortho position was 0.75.
[0047]
Production Example 3
425 g of epoxy resin (c) was obtained in the same manner as in Production Example 1, except that the temperature in the system after addition of dicyclopentagen during the production of the intermediate was changed from 110 ° C. to 120 ° C. This resin was a brown solid and had a softening point of 65 ° C., a melt viscosity of 0.8 poise at 150 ° C., and an epoxy equivalent of 260 g / eq. The ratio of para position to ortho position was 0.82.
[0048]
Production Example 4
Same as Production Example 1 except that 940 g (10 mol) of phenol in the production of the intermediate was changed to 752 g (8 mol) of phenol, and the system temperature after addition of dicyclopentagen was changed from 110 ° C. to 100 ° C. Thus, 430 g of an epoxy resin ( d ) was obtained. This resin was a brown solid and had a softening point of 67 ° C., a melt viscosity of 0.9 poise at 150 ° C., and an epoxy equivalent of 262 g / eq. The ratio between the para position and the ortho position was 0.61.
[0049]
Production Example 5
Production Example 1 except that 940 g (10 mol) of phenol in the production of the intermediate was changed to 658 g (7 mol) of phenol, and the system temperature after addition of dicyclopentagen was changed from 110 ° C. to 90 ° C. Similarly, 428 g of an epoxy resin (e) was obtained. This resin was a brown solid with a softening point of 68 ° C., a melt viscosity of 1.1 poise at 150 ° C., and an epoxy equivalent of 262 g / eq. The ratio between the para position and the ortho position was 0.53.
[0050]
Production Comparative Example 1
In the same manner as in Production Example 1 except that the system temperature after addition of dicyclopentagen during the production of the intermediate was changed from 110 ° C. to 60 ° C. and the reaction time was changed from 3 hours to 10 hours, an epoxy resin ( f) 425 g was obtained. This resin was a brown solid and had a softening point of 64 ° C., a melt viscosity of 0.7 poise at 150 ° C., and an epoxy equivalent of 260 g / eq. The ratio of para position to ortho position was 0.42.
[0051]
Production Comparative Example 2
In the same manner as in Production Example 1 except that the system temperature after addition of dicyclopentagen during the production of the intermediate was changed from 110 ° C. to 70 ° C. and the reaction time was changed from 3 hours to 6 hours, an epoxy resin ( g) 425 g was obtained. This resin was a brown solid and had a softening point of 64 ° C., a melt viscosity of 0.7 poise at 150 ° C., and an epoxy equivalent of 260 g / eq. The ratio of para position to ortho position was 0.48.
[0052]
Production Comparative Example 3
In the same manner as in Production Example 4 except that the system temperature after addition of dicyclopentagen during the production of the intermediate was changed from 110 ° C. to 70 ° C. and the reaction time was changed from 3 hours to 6 hours, an epoxy resin ( h) 425 g was obtained. This resin was a brown solid and had a softening point of 66 ° C., a melt viscosity of 0.9 poise at 150 ° C., and an epoxy equivalent of 262 g / eq. The ratio between the para position and the ortho position was 0.37.
[0053]
Production Comparative Example 4
In the same manner as in Production Example 2, except that the system temperature after the addition of dicyclopentagen during the production of the intermediate was changed from 110 ° C. to 70 ° C. and the reaction time was changed from 3 hours to 6 hours, an epoxy resin ( i) 425 g was obtained. This resin was a brown solid and had a softening point of 79 ° C., a melt viscosity of 3.4 poise at 150 ° C., and an epoxy equivalent of 264 g / eq. The ratio between the para position and the ortho position was 0.33.
[0054]
Examples 1 to 3 and Comparative Examples 1 to 6
A mixture prepared according to the formulation shown in Table 1 and Table 2 is kneaded with a hot roll at 100 ° C. for 8 minutes, and then pulverized to produce a tablet at a pressure of 1200-1400 Kg / cm ² . Using this, it was sealed with a transfer molding machine under the conditions of a plunger pressure of 80 kg / cm ² , a mold temperature of 175 ° C., and a molding time of 100 seconds, and a flat package having a thickness of 2 mm was prepared as a test piece for evaluation. . Thereafter, post-curing was performed at 175 ° C. for 8 hours. In addition, the compounding quantity of the fused silica was adjusted so that the fluidity | liquidity of the obtained compound might become the same. Further, phenolite TD-2131 (manufactured by Dainippon Ink & Chemicals, Inc .: hydroxyl group equivalent 107 g / eq., Number of nuclei 5) was used as a phenol novolac curing agent.
[0055]
Using this test specimen for evaluation, the water absorption under the conditions of 85 ° C. and 85% RH, the glass transition temperature by DMA, and the dynamic viscoelastic modulus were measured. Further, after leaving the test piece in an atmosphere of 85 ° C. and 85% RH for 72 hours and performing a moisture absorption treatment, the test piece was immersed in a solder bath at 260 ° C. for 10 seconds, and the crack generation rate at that time was examined to determine the resistance to resistance. Solder cracking property was evaluated. There are 20 test pieces. The results are also shown in Tables 1 and 2 .
[0056]
[Table 1]

[0057]
[Table 2]

[0058]
【The invention's effect】
According to the present invention, an epoxy resin composition that can be a cured product excellent in low moisture absorption and heat resistance, and a semiconductor sealing material that is excellent in the effect of preventing solder cracks due to low moisture absorption and also excellent in heat resistance Can provide.

Claims (5)

A divalent hydrocarbon group based on an unsaturated bond in the molecular structure of dicyclopentadiene is used as a linking group , and phenol, m-cresol, 3,5-xylenol, and an alkyl group having 2 to 6 carbon atoms at the m-position. A group comprising alkylphenol having, dialkylphenol having an alkyl group having 2 to 6 carbon atoms in the 3,5-position, m-chlorophenol, m-bromophenol, 3,5-dichlorophenol, and 3,5-dibromophenol A polyglycidyl ether of a polyaddition compound bonded to a phenol selected from the group consisting of a polyglycidyl ether having a melt viscosity at 150 ° C. of 1.0 poise or less and bonded to the aromatic ring of the phenol. ratio of para and ortho substitution position of Semmoto is, epoxy 0.5-1 by the value of para / ortho position by measuring C ¹³ -NMR Epoxy resin composition, characterized in that the fat (A) and curing agent (B) an essential component. The composition according to claim 1 , wherein the curing agent (B) is a phenol novolac resin. A divalent hydrocarbon group based on an unsaturated bond in the molecular structure of dicyclopentadiene is used as a linking group , and phenol, m-cresol, 3,5-xylenol, and an alkyl group having 2 to 6 carbon atoms at the m-position. A group comprising alkylphenol having, dialkylphenol having an alkyl group having 2 to 6 carbon atoms in the 3,5-position, m-chlorophenol, m-bromophenol, 3,5-dichlorophenol, and 3,5-dibromophenol A polyglycidyl ether of a polyaddition compound bonded to a phenol selected from the group consisting of a polyglycidyl ether having a melt viscosity at 150 ° C. of 1.0 poise or less and bonded to the aromatic ring of the phenol. ratio of para and ortho substitution position of Semmoto is, epoxy 0.5-1 by the value of para / ortho position by measuring C ¹³ -NMR Fat (A), a semiconductor encapsulating material, characterized in that the curing agent (B) and the inorganic filler (C) as essential components. The semiconductor sealing material according to claim 3 , wherein the curing agent (B) is phenol novolac. The semiconductor sealing material according to claim 3 or 4 , wherein a filling factor in the composition of the inorganic filler (C) is 75 to 95% by weight.