JP3674675B2 - Underfill material for flip chip type semiconductor devices - Google Patents

Underfill material for flip chip type semiconductor devices Download PDF

Info

Publication number
JP3674675B2
JP3674675B2 JP2000067640A JP2000067640A JP3674675B2 JP 3674675 B2 JP3674675 B2 JP 3674675B2 JP 2000067640 A JP2000067640 A JP 2000067640A JP 2000067640 A JP2000067640 A JP 2000067640A JP 3674675 B2 JP3674675 B2 JP 3674675B2
Authority
JP
Japan
Prior art keywords
epoxy resin
underfill material
weight
spherical
group
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
JP2000067640A
Other languages
Japanese (ja)
Other versions
JP2000327884A (en
Inventor
邦雄 伊藤
利夫 塩原
和昌 隅田
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shin Etsu Chemical Co Ltd
Original Assignee
Shin Etsu Chemical Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shin Etsu Chemical Co Ltd filed Critical Shin Etsu Chemical Co Ltd
Priority to JP2000067640A priority Critical patent/JP3674675B2/en
Publication of JP2000327884A publication Critical patent/JP2000327884A/en
Application granted granted Critical
Publication of JP3674675B2 publication Critical patent/JP3674675B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L24/00—Arrangements for connecting or disconnecting semiconductor or solid-state bodies; Methods or apparatus related thereto
    • H01L24/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L24/26—Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L24/31—Structure, shape, material or disposition of the layer connectors after the connecting process
    • H01L24/32—Structure, shape, material or disposition of the layer connectors after the connecting process of an individual layer connector
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/10—Bump connectors; Manufacturing methods related thereto
    • H01L2224/15—Structure, shape, material or disposition of the bump connectors after the connecting process
    • H01L2224/16—Structure, shape, material or disposition of the bump connectors after the connecting process of an individual bump connector
    • H01L2224/161—Disposition
    • H01L2224/16151—Disposition the bump connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive
    • H01L2224/16221—Disposition the bump connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked
    • H01L2224/16225—Disposition the bump connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being non-metallic, e.g. insulating substrate with or without metallisation
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/26—Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L2224/31—Structure, shape, material or disposition of the layer connectors after the connecting process
    • H01L2224/32—Structure, shape, material or disposition of the layer connectors after the connecting process of an individual layer connector
    • H01L2224/321—Disposition
    • H01L2224/32151—Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive
    • H01L2224/32221—Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked
    • H01L2224/32225—Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being non-metallic, e.g. insulating substrate with or without metallisation
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/73—Means for bonding being of different types provided for in two or more of groups H01L2224/10, H01L2224/18, H01L2224/26, H01L2224/34, H01L2224/42, H01L2224/50, H01L2224/63, H01L2224/71
    • H01L2224/732—Location after the connecting process
    • H01L2224/73201—Location after the connecting process on the same surface
    • H01L2224/73203—Bump and layer connectors
    • H01L2224/73204—Bump and layer connectors the bump connector being embedded into the layer connector
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/83—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector
    • H01L2224/83909—Post-treatment of the layer connector or bonding area
    • H01L2224/83951—Forming additional members, e.g. for reinforcing, fillet sealant
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01004—Beryllium [Be]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01005—Boron [B]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01006—Carbon [C]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01012—Magnesium [Mg]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01013—Aluminum [Al]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01015—Phosphorus [P]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01019—Potassium [K]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01027—Cobalt [Co]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01029—Copper [Cu]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01033—Arsenic [As]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01045—Rhodium [Rh]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/013—Alloys
    • H01L2924/0132—Binary Alloys
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/10—Details of semiconductor or other solid state devices to be connected
    • H01L2924/102—Material of the semiconductor or solid state bodies
    • H01L2924/1025—Semiconducting materials
    • H01L2924/10251—Elemental semiconductors, i.e. Group IV
    • H01L2924/10253—Silicon [Si]

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Compositions Of Macromolecular Compounds (AREA)
  • Epoxy Resins (AREA)
  • Structures Or Materials For Encapsulating Or Coating Semiconductor Devices Or Solid State Devices (AREA)
  • Wire Bonding (AREA)
  • Encapsulation Of And Coatings For Semiconductor Or Solid State Devices (AREA)

Abstract

PROBLEM TO BE SOLVED: To obtain an underfill material which is excellent in preservation stabilty and penetration into gaps and gives a highly reliable cured item by incorporating a liquid epoxy resin, spherical silica prepared by heating and burning spherical polyorganosilsesquioxane particles, and a cure accelerator into the same. SOLUTION: This underfill material for flip-chip semiconductor devices contains 100 pts.wt. liquid epoxy resin; 100-300 pts.wt. spherical silica which is prepared by heating and burning spherical polyorganosilsesquioxane particles, has a max. particle size of 50 μm or lower and an average particle size of 0.5-10 μm, and contains 0.005-0.1 wt.% carbon particles on the surface; and 0.01-10 pts.wt. cure accelerator. A flip-chip semiconductor device has such a structure that a semiconductor chip 3 is mounted, via a plurality of bumps 2, on the wiring pattern face of an organic substrate 1; the gaps between the organic substrate 1 and the semiconductor chip 3 are filled with the underfill material 4; and the side is sealed with a fillet material 5.

Description

【０００１】
【発明の属する技術分野】
本発明は、フリップチップ型半導体装置用のアンダーフィル材に関する。
【０００２】
【従来の技術及び発明が解決しようとする課題】
電気機器の小型、軽量化、高機能化に伴い、半導体の実装方法もピン挿入タイプから表面実装が主流になっている。そして、ベアチップ実装の一つにフリップチップ（ＦＣ）実装がある。ＦＣ実装とは、ＬＳＩチップの配線パターン面に高さ１０〜１００μｍ程度のバンプといわれる電極を数個から数千個形成し、基板の電極を導電ペースト或いは半田等で接合する方式である。このため、ＦＣの保護に用いる封止材料は、基板とＬＳＩチップのバンプ等による数１０μｍ程度の隙間に浸透させる必要がある。従来のフリップチップ用アンダーフィル材として使用される液状エポキシ樹脂組成物は、エポキシ樹脂と硬化剤及び無機質充填剤を配合し、信頼性を高めるために半導体のチップや基板、バンプと線膨張係数を一致させるために、多量の無機質充填剤を配合する処方が主流となってきている。
【０００３】
しかしながら、このような充填剤を高充填したフリップチップ用アンダーフィル材においては、応力特性においては何ら問題はなくなってきているが、一方では充填剤の高充填化により粘度が高くなり、チップと基板の隙間に侵入する速度が著しく低下し、生産性が非常に悪くなるといった問題点が提示されており、この問題点の改善が望まれる。
【０００４】
また、無機質充填剤を多量に充填する場合、充填剤の粒度分布や充填剤表面の状態が最終製品の粘度に大きく影響を及ぼすことがよく知られている。そのため、従来は火炎溶融で得られる球状シリカをエアー分級や篩を用いて粗粒や微粉を除去したり、また、粒度の異なる球状シリカを組み合わせることで最適な粒度分布を調整していた。この方法では収率が非常に悪いため原料価格が高くなるといった問題がある。
【０００５】
更に、従来はシリカ表面とエポキシ樹脂の親和性や接着強度を改善するため、シランカップリング剤のような表面改質剤を用いることが通常行われている。しかし、アンダーフィル材の場合、非常に狭い間隙で加熱硬化されることから、微量の揮発成分であってもボイドの原因となるといった問題が発生している。
【０００６】
本発明は、上記事情に鑑みなされたもので、多量の無機質充填剤を配合しても、低粘度で隙間侵入させることが可能で、かつボイド等の発生のない信頼性の優れた硬化物を与えるフリップチップ型半導体装置用アンダーフィル材を提供することを目的とする。
【０００７】
【課題を解決するための手段及び発明の実施の形態】
本発明者は、上記目的を達成するため鋭意検討を重ねた結果、フリップチップ型半導体装置のアンダーフィル材として用いるエポキシ樹脂組成物において、無機質充填剤として、ポリオルガノシルセスキオキサン球状粒子を加熱燃焼させて得られる球状シリカ、特に最大粒径が５０μｍ以下、平均粒径が０．５〜１０μｍで、表面に炭素原子を含有した球状シリカを使用することにより、エポキシ樹脂との親和性が改善され、多量の無機質充填剤（上記球状シリカ）を配合しても狭間部への隙間侵入性が著しく改善され、半導体装置の信頼性を高めることができることを見出し、本発明をなすに至った。
【０００８】
従って、本発明は、
（Ａ）液状エポキシ樹脂：１００重量部
（Ｂ）ポリオルガノシルセスキオキサン球状粒子を加熱燃焼させることにより得られる０．００５〜０．１重量％の表面残存炭素原子を有する球状シリカ：１００〜３００重量部
（Ｃ）硬化促進剤：０．０１〜１０重量部
を含有してなることを特徴とするフリップチップ型半導体装置用アンダーフィル材を提供する。
【０００９】
以下、本発明について更に詳しく説明する。
本発明に用いられる上記（Ａ）成分の液状のエポキシ樹脂は、一分子中に２個以上のエポキシ基があればいかなるものでも使用可能であるが、特に、ビスフェノールＡ型エポキシ樹脂、ビスフェノールＦ型エポキシ樹脂等のビスフェノール型エポキシ樹脂、フェノールノボラック型エポキシ樹脂、クレゾールノボラック型エポキシ樹脂等のノボラック型エポキシ樹脂、トリフェノールメタン型エポキシ樹脂、トリフェノールプロパン型エポキシ樹脂等のトリフェノールアルカン型エポキシ樹脂、ナフタレン型エポキシ樹脂、ビフェニル型エポキシ樹脂、シクロペンタジエン型エポキシ樹脂などが例示される。この中でも室温で液状のエポキシ樹脂を使用するが、特にビスフェノールＡ型エポキシ樹脂、ビスフェノールＦ型エポキシ樹脂等のビスフェノール型エポキシ樹脂が望ましい。これらのエポキシ樹脂には、下記構造で示されるエポキシ樹脂を浸入性に影響を及ぼさない範囲で添加しても何ら問題はない。
【００１０】
【化１】

Figure 0003674675
【００１１】
上記液状エポキシ樹脂中の全塩素含有量は、１５００ｐｐｍ以下、望ましくは１０００ｐｐｍ以下であることが好ましい。また、１２０℃で５０％エポキシ樹脂濃度における２０時間での抽出水塩素が５ｐｐｍ以下であることが好ましい。全塩素含有量が１５００ｐｐｍを超え、抽出水塩素が５ｐｐｍを超えると、半導体素子の信頼性、特に耐湿性に悪影響を与えるおそれがある。
【００１２】
次に、本発明の（Ｂ）成分の球状シリカは、ポリオルガノシルセスキオキサン球状粒子を加熱燃焼させることにより得られたものを使用する。この場合、ポリオルガノシルセスキオキサンとしては、ポリメチルシルセスキオキサン、ポリエチルシルセスキオキサン等に代表されるポリアルキルシルセスキオキサンなどが挙げられる。これらの中で、ポリオルガノシルセスキオキサン球状粉末としては、特にポリオルガノシルセスキオキサン球状粉末が好ましい。
【００１３】
ここで、本発明で使用する球状シリカの原料であるポリオルガノシルセスキオキサンは特公平６−３３３３７号公報記載の方法に準じ、３官能性オルガノアルコキシシラン又はその部分加水分解物と有機溶剤の混合物をアルカリ性物質を含む水溶液中で撹拌下加水分解縮合させた後、得られた球状の樹脂を中和することで容易に得ることができ、この方法で狭い粒度分布を有するポリオルガノシルセスキオキサン粒子を得ることができる。この場合、３官能性オルガノアルコキシシランとしては、メチルトリメトキシシラン、メチルトリエトキシシラン、メチルトリプロポキシシラン、あるいはこれらシランのメチル基をエチル基、プロピル基、ブチル基等の他の低級アルキル基などの一価炭化水素基で置換したシランが挙げられ、中でもメチルトリアルコキシシラン、エチルトリアルコキシシラン等のアルキルトリアルコキシシランを好ましく用いることができる。
【００１４】
上記ポリオルガノシルセスキオキサンの粒子は平均粒径が０．５〜１０μｍ、特に１〜５μｍのもので、粒子径の分布が平均粒径の±３０％の範囲にあるものの割合が８０％（重量％、以下同じ）以上あることが好ましい。このポリオルガノシルセスキオキサンを４００〜１０００℃の温度で燃焼させ、焼結させることで、容易に実質的に原料のポリオルガノシルセスキオキサンと同じ粒度分布（最大粒径、平均粒径）をもった球状のシリカを得ることができるものである。
【００１５】
この場合、本発明では、更に空気中での燃焼に際し、酸素の量をコントロールすることで珪素−炭素結合の酸化分解を抑え、シリカ表面上に適量の炭素を残存させることによって、液状エポキシ樹脂とフィラー表面の親和性を高めることができる。表面に残存する炭素としてはシリカ粒子全体に対して重量で０．００５〜０．１％、望ましくは０．０１〜０．０８％である。０．００５％より少ないと十分な親和性が得られない場合があり、また、０．１％より多いとＳｉＣの存在量が多くなり、導電性を帯びてくるため、絶縁材料としては適さなくなるおそれが生じる。従って、炭素が全く存在しないものより若干でも炭素が残存したものを用いた方が、フリップチップ型半導体装置の狭いギャップに樹脂を短時間で侵入させることができる点でより好ましい。
【００１６】
この方法で得られた炭素を好ましくは上記特定量含有するシリカ球状粒子を用いることで、従来より少ない量のカップリング剤で従来並の硬化物特性が得られ、かつ揮発成分が原因となるボイド不良の発生も少なく、半導体装置としての高信頼性を確保することができる。また、樹脂と充填剤の親和性が改善されることから、エポキシ樹脂組成物として粘度を下げることが可能となり、侵入性の向上と低線膨張化のための高充填化を両立させることが可能となる。
【００１７】
これらシリカの特性としては侵入性の向上を図るためフリップチップギャップ幅に対して平均粒径が約１／１０以下、最大粒径が１／２以下が望ましく、通常は最大粒径５０μｍ以下、望ましくは２５μｍ以下、更に望ましくは１０μｍ以下である。平均粒径は１０μｍ以下（通常、０．５〜１０μｍ）、望ましくは５μｍ以下、より望ましくは１〜５μｍである。
【００１８】
上記球状シリカの配合量としては液状エポキシ樹脂１００重量部に対し１００〜３００重量部、特に液状エポキシ樹脂１００重量部に対し１００〜２５０重量部の範囲が好ましい。配合量が少ないと膨張係数が大きく、冷熱試験においてクラックの発生を誘発させる。また、配合量が多いと、粘度が高くなり、薄膜侵入性の低下をもたらす。
【００１９】
なお、本発明において、上記球状シリカの表面炭素量は、カーボン量分析装置を用い、１３００℃でシリカを加熱することで発生する炭酸ガスを定量することにより測定した値であり、通常、粒子表面の炭素量である。また、平均粒径は、例えばレーザー光回折法等による重量平均値（又はメディアン径）等として求めることができる。
【００２０】
本発明のアンダーフィル材には、上記ポリオルガノシルセスキオキサンを加熱焼成して得られる球状シリカに加えて、他の無機質充填剤を配合することができる。この無機質充填剤としては、球状又は破砕状の溶融シリカ、結晶シリカ、ゾル−ゲル法により得られる球状シリカ等のシリカ微粉末、アルミナ、ボロンナイトライド、チッ化アルミ、チッ化珪素、マグネシア、マグネシウムシリケート等を挙げることができ、中でも球状溶融シリカが好ましい。この場合、上記任意成分としての無機質充填剤も、（Ｂ）成分の球状シリカと同様に、最大粒径が５０μｍ以下、望ましくは２５μｍ以下、更に望ましくは１０μｍ以下であり、平均粒径が１０μｍ以下、通常０．５〜１０μｍ、望ましくは１〜５μｍ程度のものを使用することが好ましい。
【００２１】
上記（Ｂ）成分の球状シリカに任意成分の無機質充填剤を併用する場合には、（Ｂ）成分を含めた無機質充填剤全体に対する（Ｂ）成分の配合割合は、６０重量％以上（即ち、６０〜１００重量％）、特に６５〜９９重量％、とりわけ８０〜９９重量％とすることが好ましい。
【００２２】
本発明の（Ｃ）成分は硬化促進剤であり、硬化促進剤としては公知のものを使用することができる。具体的には、イミダゾール化合物及び３級アミン化合物、有機リン系化合物から選ばれる１種又は２種以上を配合することができる。ここで、イミダゾール化合物としては、２−メチルイミダゾール、２−エチルイミダゾール、４−メチルイミダゾール、４−エチルイミダゾール、２−フェニルイミダゾール、２−フェニル−４−メチルイミダゾール、２−フェニル−４−ヒドロキシメチルイミダゾール、２−エチル−４−メチルイミダゾール、１−シアノエチル−２−メチルイミダゾール、２−フェニル−４−メチル−５−ヒドロキシメチルイミダゾール、２−フェニル−４，５−ジヒドロキシメチルイミダゾール等が挙げられる。また、３級アミン化合物としては、トリエチルアミン、ベンジルトリメチルアミン、α−メチルベンジルジメチルアミン等の窒素原子に結合する置換基としてアルキル基やアラルキル基を有するアミン化合物、１，８−ジアザヒシクロ［５．４．０］ウンデセン−７及びそのフェノール塩、オクチル酸塩、オレイン酸塩などのシクロアミジン化合物やその有機酸との塩、或いは下記式の化合物などのシクロアミジン化合物と４級ホウ素化合物との塩又は錯塩などが挙げられる。
【００２３】
【化２】
Figure 0003674675
【００２４】
また、有機リン系化合物としては、トリフェニルホスフィン等のトリオルガノホスフィン化合物やテトラフェニルホスホニウムテトラフェニルボレート等の４級ホスホニウム塩などが挙げられる。
【００２５】
その配合量は、上記エポキシ樹脂１００重量部に対して０．０１〜１０重量部、望ましくは０．５〜５重量部である。０．０１重量部より少ないと硬化性が低下し、１０重量部より多いと硬化性に優れるが、保存性が低下する傾向となる。
【００２６】
ここで、上記エポキシ樹脂は、上記硬化促進剤単独でも硬化させることができるが、必要によっては、硬化剤として例えば、テトラヒドロ無水フタル酸、メチルテトラヒドロ無水フタル酸、メチルヘキサヒドロ無水フタル酸、ヘキサヒドロ無水フタル酸、無水メチルハイミック酸、ピロメリット酸二無水物、ベンゾフェノンテトラカルボン酸二無水物、３，３’，４，４’−ビフェニルテトラカルボン酸二無水物、ビス（３，４−ジカルボキシフェニル）エーテル二無水物、ビス（３，４−ジカルボキシフェニル）メタン二無水物、２，２−ビス（３，４−ジカルボキシフェニル）プロパン二無水物などの、好ましくは分子中に脂肪族環又は芳香族環を１個又は２個有すると共に、酸無水物基（即ち、−ＣＯ−Ｏ−ＣＯ−基）を１個又は２個有する、炭素原子数４〜２５個、好ましくは８〜２０個程度の酸無水物や、ジシアンジアミド、アジピン酸ヒドラジド、イソフタル酸ヒドラジドなどのカルボン酸ヒドラジドを使用することができる。
【００２７】
なお、酸無水物を硬化剤として用いる場合は、エポキシ樹脂中のエポキシ基１モルに対し、硬化剤中の酸無水物基の比を０．３〜０．７モルの範囲とすることが望ましい。０．３モル未満では硬化性が不十分であり、０．７モルを超えると、未反応の酸無水物が残存し、ガラス転移温度の低下となるおそれがある。より望ましくは０．４〜０．６モルの範囲である。
【００２８】
本発明の組成物には、応力を低下させる目的でシリコーンゴム、シリコーンオイルや液状のポリブタジエンゴム、メタクリル酸メチル−ブタジエン−スチレン共重合体といった熱可塑性樹脂などを配合してもよい。好ましくは、アルケニル基含有エポキシ樹脂又はフェノール樹脂のアルケニル基と、下記式（１）で示される一分子中の珪素原子の数が２０〜４００、好ましくは４０〜２００であり、ＳｉＨ基の数が１〜５であるオルガノポリシロキサンのＳｉＨ基との付加反応により得られる共重合体を配合することがよい。
ＨaＲbＳｉＯ(4-a-b)/2 （１）
（式中、Ｒは置換又は非置換の一価炭化水素基、ａは０．００５〜０．１、ｂは１．８〜２．２、１．８１≦ａ＋ｂ≦２．３を満足する正数を示す。）
【００２９】
なお、Ｒの一価炭化水素基としては、炭素数１〜１０、特に１〜８のものが好ましく、メチル基、エチル基、プロピル基、イソプロピル基、ブチル基、イソブチル基、ｔｅｒｔ−ブチル基、ヘキシル基、シクロヘキシル基、オクチル基、デシル基等のアルキル基、ビニル基、アリル基、プロペニル基、ブテニル基、ヘキセニル基等のアルケニル基、フェニル基、キシリル基、トリル基等のアリール基、ベンジル基、フェニルエチル基、フェニルプロピル基等のアラルキル基などや、これらの炭化水素基の水素原子の一部又は全部を塩素、フッ素、臭素等のハロゲン原子で置換したクロロメチル基、ブロモエチル基、トリフルオロプロピル基等のハロゲン置換一価炭化水素基を挙げることができる。
上記共重合体としては、中でも下記構造のものが望ましい。
【００３０】
【化３】
Figure 0003674675
【００３１】
【化４】
Figure 0003674675
（上記式中、Ｒは上記と同じ、Ｒ1は水素原子又は炭素数１〜４のアルキル基、Ｒ2は−ＣＨ2ＣＨ2ＣＨ2−、−ＯＣＨ2−ＣＨ（ＯＨ）−ＣＨ2−Ｏ−ＣＨ2ＣＨ2ＣＨ2−又は−Ｏ−ＣＨ2ＣＨ2ＣＨ2−である。ｎは４〜１９９、好ましくは１９〜９９の整数、ｐは１〜１０の整数、ｑは１〜１０の整数である。）
【００３２】
上記共重合体は、ジオルガノポリシロキサン単位が液状エポキシ樹脂と硬化剤（配合した場合）の合計量１００重量部に対し０〜２０重量部、特には２〜１５重量部含まれるように配合することで、応力をより一層低下させることができる。
【００３３】
本発明の封止材（液状エポキシ樹脂組成物）には、更に必要に応じ、接着向上用炭素官能性シラン、カーボンブラックなどの顔料、染料、酸化防止剤、表面処理剤（γ−グリシドキシプロピルトリメトキシシラン等のシランカップリング剤など）、その他の添加剤を配合することができる。
【００３４】
本発明のエポキシ樹脂組成物は、例えば、エポキシ樹脂、硬化剤、硬化促進剤、無機質充填剤を同時に又は別々に必要により加熱処理を加えながら撹拌、溶解、混合、分散させることにより製造することができる。これらの混合物の混合、撹拌、分散等の装置は特に限定されないが、撹拌、加熱装置を備えたライカイ機、３本ロール、ボールミル、プラネタリーミキサー等を用いることができる。これら装置を適宜組み合わせて使用してもよい。
【００３５】
なお、本発明における、アンダーフィル材、即ちアンダーフィル部の封止材として用いる液状エポキシ樹脂組成物の粘度は、２５℃において１０，０００ポイズ以下のものが好ましい。また、本発明のアンダーフィル材は、隙間充填性と耐熱衝撃性の点で、ガラス転移温度以下の膨張係数が２０〜４０ｐｐｍ／℃、特に２０〜３０ｐｐｍ／℃であることが好ましい。
【００３６】
本発明のアンダーフィル材はフリップチップ型半導体装置用として使用するものであるが、本発明に係るフリップチップ型半導体装置は、図１に示したように、有機基板１の配線パターン面に複数個のバンプ２を介して半導体チップ３が搭載されているものであり、上記有機基板１と半導体チップ３との間の隙間（バンプ２間の隙間）にアンダーフィル材４が充填され、その側部がフィレット材５で封止されたものである。
【００３７】
なお、上記フィレット材は特に制限されるものではなく、エポキシ樹脂組成物、特に上述したアンダーフィル材と同様の成分を有するエポキシ樹脂組成物を用いることができる（但し、無機質充填剤としては、上記球状シリカのほか、溶融シリカ、結晶シリカ、アルミナ、ボロンナイトライド、チッ化アルミ、チッ化珪素、マグネシア、マグネシウムシリケートなどが使用される）が、ガラス転移温度以下の膨張係数が２０ｐｐｍ／℃以下、好ましくは５〜１９ｐｐｍ／℃、より好ましくは１０〜１８ｐｐｍ／℃であるものを使用するのが好ましい。
【００３８】
上記アンダーフィル材の成形方法、成形条件は常法とすることができるが、好ましくは熱オーブンを用いて１５０℃で０．５時間以上の条件において硬化、成形することが好ましい。
【００３９】
【実施例】
以下、実施例と比較例を示し、本発明を具体的に説明するが、本発明は下記の実施例に制限されるものではない。
【００４０】
［実施例、比較例］
表１，２に示す成分を３本ロールで均一に混練することにより８種のエポキシ樹脂組成物を得た。これらのエポキシ樹脂組成物を用いて、以下に示す試験を行った。その結果を表１，２に示す。
【００４１】
［粘度］
ＢＨ型回転粘度計を用いて２０ｒｐｍの回転数で２５℃における粘度を測定した。
［チキソ比］
ＢＨ型回転粘度計を用いて２ｒｐｍと２０ｒｐｍの粘度の比を２５℃におけるチキソ比とした。
［ゲル化時間］
組成物のゲル化時間を１５０℃の熱板上で測定した。
［Ｔｇ］：ガラス転移温度
５ｍｍ×５ｍｍ×１５ｍｍの硬化物サンプルを用いてＴＭＡ（熱機械分析装置）により５℃／分の速度で昇温した際の値を測定した。
［ＣＴＥ−１］：Ｔｇ以下の膨張係数
［ＣＴＥ−２］：Ｔｇ以上の膨張係数
上記ガラス転移温度の測定において、ＣＴＥ−１は５０〜８０℃の温度範囲、ＣＴＥ−２は２００〜２３０℃の温度範囲における値を求めた。
［侵入試験］及び［ボイド不良］
図２（Ａ），（Ｂ）に示したように、熱板１１上に下側スライドガラス１２を載置し、その上にそれぞれ厚さ８０μｍの２枚のポリイミドフィルム１３，１３を１ｃｍの間隔を隔ててセットし、その上から上側スライドガラス１４を被せ、上記両スライドガラス１２，１４と２枚のポリイミドフィルム１３，１３とにより、幅１ｃｍ、高さ８０μｍの間隙１５を形成した。上記下側スライドガラス１２上にエポキシ樹脂組成物１６を置き、熱板１１を１００℃に設定した時、上記組成物１６が上記間隙１５に２０ｍｍの距離まで浸透、到達するまでの時間を測定した。
［超音波探傷装置によるボイドの観察］
４００個のバンプを有する１０ｍｍ×１０ｍｍのシリコンチップをＢＴ基板に搭載し、２３℃／６０％ＲＨの雰囲気に２時間放置した後、このデバイスの一片にディスペンサーでそれぞれの組成物を滴下し、封止した。封止後、加熱硬化させた後に超音波探傷装置を用い、ボイド（内部ボイド）の検出を行った。評価はアンダーフィル材硬化物の封止面積に対するボイドのトータル面積割合で示した。
［熱衝撃性不良率］
銅フレームの上にエポキシ樹脂組成物を均一に塗布して、１０ｍｍ×１０ｍｍにカットした０．６ｍｍ厚のシリコンウエハーを樹脂上にのせ、１５０℃で４時間硬化させて得られた試験片を−５５℃×１分〜１６０℃×３０秒の熱サイクルを繰り返して、１００サイクル後にエポキシ樹脂組成物のクラック及び剥離が発生しているものを不良とし、不良率を測定した（試験数＝２０）。
【００４２】
【表１】
Figure 0003674675
【００４３】
【表２】
Figure 0003674675
【００４４】
使用原料
（１）ＲＥ３１０：ビスフェノールＡ型エポキシ樹脂（日本化薬（株）製）
（２）ＲＥ３０４：ビスフェノールＦ型エポキシ樹脂（日本化薬（株）製）
（３）ＭＨ７００：メチルテトラヒドロ無水フタル酸（新日本理化（株）製）
（４）下記表３に示すシリカ
（５）ＫＢＭ４０３：γ−グリシドキシプロピルトリメトキシシラン（信越化学工業（株）製）
（６）２Ｐ４ＭＺ：２−フェニル−４−メチルイミダゾール（四国化成（株）製）
（７）ＨＸ３７４１：イミダゾ−ル化合物を含有するマイクロカプセル化触媒（旭チバ（株）製）
【００４５】
【表３】
Figure 0003674675
＊ ＳＯ３２Ｈ：アドマテクス（株）製
【００４６】
【発明の効果】
本発明のフリップチップ型半導体装置用アンダーフィル材は、薄膜侵入性、保存安定性に優れており、このアンダーフィル材を用いた半導体装置は非常に信頼性の高いものである。
【図面の簡単な説明】
【図１】フリップチップ型半導体装置の一例を示す概略図である。
【図２】侵入試験で用いたテストピースを示し、（Ａ）は側面図、（Ｂ）は平面図である。
【符号の説明】
１ 有機基板
２ バンプ
３ 半導体チップ
４ アンダーフィル材
５ フィレット材
１１ 熱板
１２ 下側スライドガラス
１３ ポリイミドフィルム
１４ 上側スライドガラス
１５ 間隙
１６ エポキシ樹脂組成物[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an underfill material for a flip chip type semiconductor device.
[0002]
[Prior art and problems to be solved by the invention]
As electrical devices become smaller, lighter, and more functional, semiconductor mounting methods have become mainstream from pin insertion type to surface mounting. One type of bare chip mounting is flip chip (FC) mounting. The FC mounting is a method in which several to several thousand electrodes called bumps having a height of about 10 to 100 μm are formed on the wiring pattern surface of an LSI chip, and the electrodes on the substrate are joined with a conductive paste or solder. For this reason, the sealing material used for protecting the FC needs to penetrate into a gap of about several tens of μm between the substrate and the bumps of the LSI chip. Liquid epoxy resin composition used as a conventional flip-chip underfill material contains an epoxy resin, a curing agent and an inorganic filler. In order to increase reliability, semiconductor chips, substrates, bumps and linear expansion coefficients are used. In order to make it coincide, prescriptions containing a large amount of inorganic filler have become mainstream.
[0003]
However, in the flip-chip underfill material highly filled with such a filler, there is no problem in the stress characteristics, but on the other hand, the higher the filler, the higher the viscosity, the chip and the substrate. There is a problem that the speed of entering the gap is remarkably reduced and the productivity is extremely deteriorated. Improvement of this problem is desired.
[0004]
In addition, when a large amount of inorganic filler is filled, it is well known that the particle size distribution of the filler and the state of the filler surface greatly affect the viscosity of the final product. Therefore, conventionally, spherical particles obtained by flame melting have been adjusted to have an optimum particle size distribution by removing coarse particles and fine powders using air classification or a sieve, or by combining spherical silicas having different particle sizes. This method has a problem that the raw material price becomes high because the yield is very poor.
[0005]
Furthermore, conventionally, in order to improve the affinity and adhesive strength between the silica surface and the epoxy resin, it is usual to use a surface modifier such as a silane coupling agent. However, in the case of an underfill material, since it is heated and cured in a very narrow gap, there is a problem that even a trace amount of volatile components causes voids.
[0006]
The present invention has been made in view of the above circumstances, and even when a large amount of an inorganic filler is blended, it is possible to allow a gap to enter with a low viscosity and to have a highly reliable cured product free from the occurrence of voids or the like. An object of the present invention is to provide an underfill material for a flip chip type semiconductor device.
[0007]
Means for Solving the Problem and Embodiment of the Invention
As a result of intensive investigations to achieve the above object, the present inventors have heated polyorganosilsesquioxane spherical particles as inorganic fillers in an epoxy resin composition used as an underfill material for flip chip type semiconductor devices. Spherical silica obtained by burning, especially with a maximum particle size of 50 μm or less, average particle size of 0.5 to 10 μm, and using spherical silica containing carbon atoms on the surface improves affinity with epoxy resin The inventors have found that even when a large amount of an inorganic filler (the above spherical silica) is blended, the gap penetration into the narrow portion is remarkably improved and the reliability of the semiconductor device can be improved, and the present invention has been made.
[0008]
Therefore, the present invention
(A) Liquid epoxy resin: 100 parts by weight (B) Spherical silica having 0.005-0.1% by weight surface residual carbon atoms obtained by heating and burning polyorganosilsesquioxane spherical particles: 100- 300 parts by weight (C) Curing accelerator: 0.01-10 parts by weight An underfill material for a flip chip type semiconductor device is provided.
[0009]
Hereinafter, the present invention will be described in more detail.
The liquid epoxy resin of the component (A) used in the present invention can be used as long as it has two or more epoxy groups in one molecule, and in particular, bisphenol A type epoxy resin, bisphenol F type Bisphenol type epoxy resin such as epoxy resin, novolak type epoxy resin such as phenol novolak type epoxy resin, cresol novolak type epoxy resin, triphenolalkane type epoxy resin such as triphenolmethane type epoxy resin, triphenolpropane type epoxy resin, naphthalene Type epoxy resin, biphenyl type epoxy resin, cyclopentadiene type epoxy resin and the like. Among these, liquid epoxy resins are used at room temperature, and bisphenol type epoxy resins such as bisphenol A type epoxy resins and bisphenol F type epoxy resins are particularly desirable. To these epoxy resins, there is no problem even if an epoxy resin represented by the following structure is added within a range that does not affect the penetration property.
[0010]
[Chemical 1]
Figure 0003674675
[0011]
The total chlorine content in the liquid epoxy resin is preferably 1500 ppm or less, more preferably 1000 ppm or less. Moreover, it is preferable that the extraction water chlorine in 20 hours in a 50% epoxy resin density | concentration at 120 degreeC is 5 ppm or less. If the total chlorine content exceeds 1500 ppm and the extracted water chlorine exceeds 5 ppm, the reliability of the semiconductor element, particularly moisture resistance, may be adversely affected.
[0012]
Next, the spherical silica which is the component (B) of the present invention is obtained by heating and burning polyorganosilsesquioxane spherical particles. In this case, examples of the polyorganosilsesquioxane include polyalkylsilsesquioxanes such as polymethylsilsesquioxane and polyethylsilsesquioxane. Among these, as the polyorganosilsesquioxane spherical powder, polyorganosilsesquioxane spherical powder is particularly preferable.
[0013]
Here, polyorganosilsesquioxane, which is a raw material of spherical silica used in the present invention, is a trifunctional organoalkoxysilane or a partially hydrolyzed product thereof and an organic solvent according to the method described in JP-B-6-33337. The mixture can be easily obtained by hydrolytic condensation with stirring in an aqueous solution containing an alkaline substance, and then neutralizing the obtained spherical resin. By this method, a polyorganosilsesquioxy having a narrow particle size distribution is obtained. Sun particles can be obtained. In this case, examples of the trifunctional organoalkoxysilane include methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, and other lower alkyl groups such as ethyl group, propyl group, and butyl group. In particular, alkyltrialkoxysilanes such as methyltrialkoxysilane and ethyltrialkoxysilane can be preferably used.
[0014]
The polyorganosilsesquioxane particles have an average particle size of 0.5 to 10 μm, particularly 1 to 5 μm, and the proportion of particles whose particle size distribution is in the range of ± 30% of the average particle size is 80% ( % By weight, the same shall apply hereinafter) or more. By burning this polyorganosilsesquioxane at a temperature of 400 to 1000 ° C. and sintering it, the particle size distribution (maximum particle size, average particle size) is easily substantially the same as that of the starting polyorganosilsesquioxane. It is possible to obtain a spherical silica having the following.
[0015]
In this case, the present invention further suppresses the oxidative decomposition of the silicon-carbon bond by controlling the amount of oxygen during combustion in air, and by leaving an appropriate amount of carbon on the silica surface, the liquid epoxy resin and The affinity of the filler surface can be increased. The carbon remaining on the surface is 0.005 to 0.1% by weight, desirably 0.01 to 0.08%, based on the entire silica particles. If the amount is less than 0.005%, sufficient affinity may not be obtained. If the amount is more than 0.1%, the abundance of SiC increases and becomes conductive, making it unsuitable as an insulating material. There is a fear. Therefore, it preferable to use those carbon remained carbon even slightly higher than those that do not exist at all, have a more preferable in terms of being able to penetrate the resin in a short time a narrow gap flip chip type semiconductor device.
[0016]
By using the silica spherical particles preferably containing the specific amount of carbon obtained by this method, it is possible to obtain conventional cured product characteristics with a smaller amount of the coupling agent and voids caused by volatile components. The occurrence of defects is small, and high reliability as a semiconductor device can be ensured. In addition, since the affinity between the resin and the filler is improved, it is possible to lower the viscosity as an epoxy resin composition, and it is possible to achieve both improved penetration and high filling for low linear expansion. It becomes.
[0017]
As for the characteristics of these silicas, the average particle size is preferably about 1/10 or less and the maximum particle size is 1/2 or less with respect to the flip chip gap width in order to improve the penetration property, and usually the maximum particle size is 50 μm or less. Is 25 μm or less, more desirably 10 μm or less. The average particle size is 10 μm or less (usually 0.5 to 10 μm), desirably 5 μm or less, and more desirably 1 to 5 μm.
[0018]
The blending amount of the spherical silica is preferably 100 to 300 parts by weight with respect to 100 parts by weight of the liquid epoxy resin, and particularly preferably 100 to 250 parts by weight with respect to 100 parts by weight of the liquid epoxy resin. If the blending amount is small, the expansion coefficient is large, and the occurrence of cracks is induced in the cold test. Moreover, when there are many compounding quantities, a viscosity will become high and will bring about the fall of thin film penetration | invasion property.
[0019]
In the present invention, the surface carbon amount of the spherical silica is a value measured by quantifying carbon dioxide generated by heating the silica at 1300 ° C. using a carbon amount analyzer, and usually the particle surface. Of carbon. In addition, the average particle diameter can be obtained as a weight average value (or median diameter) by a laser light diffraction method, for example.
[0020]
In addition to the spherical silica obtained by heating and firing the polyorganosilsesquioxane, the underfill material of the present invention can contain other inorganic fillers. Examples of the inorganic filler include spherical or crushed fused silica, crystalline silica, silica fine powder such as spherical silica obtained by a sol-gel method, alumina, boron nitride, aluminum nitride, silicon nitride, magnesia, magnesium. A silicate etc. can be mentioned, A spherical fused silica is especially preferable. In this case, the inorganic filler as the optional component also has a maximum particle size of 50 μm or less, desirably 25 μm or less, more desirably 10 μm or less, and an average particle size of 10 μm or less, similar to the spherical silica of component (B). In general, it is preferable to use one having a thickness of about 0.5 to 10 μm, desirably about 1 to 5 μm.
[0021]
When the inorganic filler of the optional component is used in combination with the spherical silica of the component (B), the blending ratio of the component (B) with respect to the entire inorganic filler including the component (B) is 60% by weight or more (that is, 60 to 100% by weight), particularly 65 to 99% by weight, and particularly preferably 80 to 99% by weight.
[0022]
(C) component of this invention is a hardening accelerator, A well-known thing can be used as a hardening accelerator. Specifically, 1 type (s) or 2 or more types chosen from an imidazole compound, a tertiary amine compound, and an organophosphorus compound can be mix | blended. Here, as the imidazole compound, 2-methylimidazole, 2-ethylimidazole, 4-methylimidazole, 4-ethylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-phenyl-4-hydroxymethyl Examples include imidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-methylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole and the like. As the tertiary amine compound, an amine compound having an alkyl group or an aralkyl group as a substituent bonded to a nitrogen atom, such as triethylamine, benzyltrimethylamine, or α-methylbenzyldimethylamine, 1,8-diazahicyclo [5.4. 0] Undecene-7 and its phenol salts, cycloamidine compounds such as octylates and oleates and salts thereof with organic acids, or salts or complex salts of cycloamidine compounds such as compounds of the following formula and quaternary boron compounds Etc.
[0023]
[Chemical formula 2]
Figure 0003674675
[0024]
Examples of the organic phosphorus compound include triorganophosphine compounds such as triphenylphosphine and quaternary phosphonium salts such as tetraphenylphosphonium tetraphenylborate.
[0025]
The blending amount is 0.01 to 10 parts by weight, desirably 0.5 to 5 parts by weight with respect to 100 parts by weight of the epoxy resin. When the amount is less than 0.01 part by weight, the curability is lowered.
[0026]
Here, the epoxy resin can be cured by the curing accelerator alone, but if necessary, as a curing agent, for example, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, hexahydroanhydride. Phthalic acid, methylhymic anhydride, pyromellitic dianhydride, benzophenone tetracarboxylic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, bis (3,4-dicarboxy) Phenyl) ether dianhydride, bis (3,4-dicarboxyphenyl) methane dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, etc., preferably aliphatic in the molecule It has one or two rings or aromatic rings and one or two acid anhydride groups (that is, —CO—O—CO— group). That, from 4 to 25 carbon atoms can preferably be used and 8 to 20 or so anhydride, dicyandiamide, adipic acid hydrazide, a carboxylic acid hydrazide such as isophthalic acid hydrazide.
[0027]
In addition, when using an acid anhydride as a hardening | curing agent, it is desirable to make the ratio of the acid anhydride group in a hardening | curing agent into the range of 0.3-0.7 mol with respect to 1 mol of epoxy groups in an epoxy resin. . If the amount is less than 0.3 mol, the curability is insufficient. If the amount exceeds 0.7 mol, unreacted acid anhydride remains, and the glass transition temperature may be lowered. More desirably, it is in the range of 0.4 to 0.6 mol.
[0028]
The composition of the present invention may contain a thermoplastic resin such as silicone rubber, silicone oil, liquid polybutadiene rubber, methyl methacrylate-butadiene-styrene copolymer for the purpose of reducing stress. Preferably, the alkenyl group of the alkenyl group-containing epoxy resin or phenol resin and the number of silicon atoms in one molecule represented by the following formula (1) are 20 to 400, preferably 40 to 200, and the number of SiH groups is A copolymer obtained by an addition reaction with SiH groups of organopolysiloxanes 1 to 5 is preferably blended.
H a R b SiO (4-ab) / 2 (1)
Wherein R is a substituted or unsubstituted monovalent hydrocarbon group, a is 0.005 to 0.1, b is 1.8 to 2.2, and 1.81 ≦ a + b ≦ 2.3. Indicates the number.)
[0029]
As the monovalent hydrocarbon group for R, those having 1 to 10 carbon atoms, particularly 1 to 8 carbon atoms are preferable, and a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, Hexyl group, cyclohexyl group, octyl group, decyl group and other alkyl groups, vinyl group, allyl group, propenyl group, butenyl group, hexenyl group and other alkenyl groups, phenyl group, xylyl group, tolyl group and other aryl groups, benzyl group , Aralkyl groups such as phenylethyl group, phenylpropyl group, etc., and chloromethyl group, bromoethyl group, trifluoro, etc. in which some or all of the hydrogen atoms of these hydrocarbon groups are substituted with halogen atoms such as chlorine, fluorine, bromine, etc. Mention may be made of halogen-substituted monovalent hydrocarbon groups such as propyl groups.
Among the above copolymers, those having the following structures are desirable.
[0030]
[Chemical 3]
Figure 0003674675
[0031]
[Formula 4]
Figure 0003674675
(In the above formula, R is the same as above, R 1 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R 2 is —CH 2 CH 2 CH 2 —, —OCH 2 —CH (OH) —CH 2 — O—CH 2 CH 2 CH 2 — or —O—CH 2 CH 2 CH 2 —, n is 4 to 199, preferably an integer of 19 to 99, p is an integer of 1 to 10, and q is 1 to 10 Is an integer.)
[0032]
The above copolymer is blended so that the diorganopolysiloxane unit is contained in an amount of 0 to 20 parts by weight, particularly 2 to 15 parts by weight with respect to 100 parts by weight of the total amount of the liquid epoxy resin and the curing agent (when blended). Thus, the stress can be further reduced.
[0033]
In the sealing material (liquid epoxy resin composition) of the present invention, if necessary, pigments such as carbon-functional silane for improving adhesion, carbon black and other pigments, dyes, antioxidants, surface treatment agents (γ-glycidoxy) Silane coupling agents such as propyltrimethoxysilane) and other additives can be blended.
[0034]
The epoxy resin composition of the present invention can be produced, for example, by stirring, dissolving, mixing, and dispersing an epoxy resin, a curing agent, a curing accelerator, and an inorganic filler simultaneously or separately while heating as necessary. it can. A device for mixing, stirring, and dispersing these mixtures is not particularly limited, and a lykai machine equipped with a stirring and heating device, a three-roll, a ball mill, a planetary mixer, and the like can be used. You may use combining these apparatuses suitably.
[0035]
In the present invention, the viscosity of the liquid epoxy resin composition used as an underfill material, that is, a sealing material for the underfill portion, is preferably 10,000 poise or less at 25 ° C. The underfill material of the present invention preferably has an expansion coefficient of 20 to 40 ppm / ° C., particularly 20 to 30 ppm / ° C. below the glass transition temperature, from the viewpoint of gap filling properties and thermal shock resistance.
[0036]
The underfill material of the present invention is used for a flip chip type semiconductor device. As shown in FIG. 1, a plurality of flip chip type semiconductor devices according to the present invention are formed on the wiring pattern surface of the organic substrate 1. The semiconductor chip 3 is mounted via the bumps 2, and the gap between the organic substrate 1 and the semiconductor chip 3 (the gap between the bumps 2) is filled with the underfill material 4, Is sealed with a fillet material 5.
[0037]
The fillet material is not particularly limited, and an epoxy resin composition, particularly an epoxy resin composition having the same components as the above-mentioned underfill material can be used (however, as the inorganic filler, In addition to spherical silica, fused silica, crystalline silica, alumina, boron nitride, aluminum nitride, silicon nitride, magnesia, magnesium silicate, etc. are used), but the expansion coefficient below the glass transition temperature is 20 ppm / ° C. or less, It is preferable to use the one having 5 to 19 ppm / ° C, more preferably 10 to 18 ppm / ° C.
[0038]
The underfill material can be molded and molded under ordinary conditions, but preferably cured and molded at 150 ° C. for 0.5 hour or longer using a thermal oven.
[0039]
【Example】
EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated concretely, this invention is not restrict | limited to the following Example.
[0040]
[Examples and Comparative Examples]
Eight types of epoxy resin compositions were obtained by uniformly kneading the components shown in Tables 1 and 2 with three rolls. The test shown below was done using these epoxy resin compositions. The results are shown in Tables 1 and 2.
[0041]
[viscosity]
The viscosity at 25 ° C. was measured at a rotation speed of 20 rpm using a BH type rotational viscometer.
[Thixo ratio]
Using a BH type rotational viscometer, the ratio of the viscosity between 2 rpm and 20 rpm was the thixo ratio at 25 ° C.
[Gelification time]
The gel time of the composition was measured on a hot plate at 150 ° C.
[Tg]: A value when the temperature was raised at a rate of 5 ° C./min by TMA (thermomechanical analyzer) using a cured product sample having a glass transition temperature of 5 mm × 5 mm × 15 mm was measured.
[CTE-1]: Expansion coefficient equal to or less than Tg [CTE-2]: Expansion coefficient equal to or greater than Tg In the measurement of the glass transition temperature, CTE-1 is a temperature range of 50 to 80 ° C., and CTE-2 is 200 to 230 ° C. The value in the temperature range was determined.
[Penetration test] and [Void defect]
As shown in FIGS. 2A and 2B, the lower slide glass 12 is placed on the hot plate 11, and two polyimide films 13 and 13 each having a thickness of 80 μm are placed on the slide glass 12 at a distance of 1 cm. The upper slide glass 14 was covered from above, and a gap 15 having a width of 1 cm and a height of 80 μm was formed by both the slide glasses 12 and 14 and the two polyimide films 13 and 13. When the epoxy resin composition 16 was placed on the lower slide glass 12 and the hot platen 11 was set at 100 ° C., the time until the composition 16 penetrated and reached the gap 15 to a distance of 20 mm was measured. .
[Void observation with an ultrasonic flaw detector]
A 10 mm × 10 mm silicon chip having 400 bumps is mounted on a BT substrate and left in an atmosphere of 23 ° C./60% RH for 2 hours. Then, each composition is dropped onto a piece of the device with a dispenser, and sealed. Stopped. After sealing and curing by heating, voids (internal voids) were detected using an ultrasonic flaw detector. Evaluation was shown by the total area ratio of the void with respect to the sealing area of hardened | cured material of an underfill material.
[Heat shock defect rate]
A test piece obtained by uniformly coating an epoxy resin composition on a copper frame, placing a 0.6 mm thick silicon wafer cut to 10 mm × 10 mm on the resin, and curing it at 150 ° C. for 4 hours— The thermal cycle of 55 ° C. × 1 minute to 160 ° C. × 30 seconds was repeated, and after 100 cycles, the cracked and peeled epoxy resin composition was regarded as defective, and the defect rate was measured (test number = 20). .
[0042]
[Table 1]
Figure 0003674675
[0043]
[Table 2]
Figure 0003674675
[0044]
Materials Used (1) RE310: Bisphenol A type epoxy resin (Nippon Kayaku Co., Ltd.)
(2) RE304: Bisphenol F type epoxy resin (manufactured by Nippon Kayaku Co., Ltd.)
(3) MH700: Methyltetrahydrophthalic anhydride (manufactured by Shin Nippon Rika Co., Ltd.)
(4) Silica shown in Table 3 below (5) KBM403: γ-glycidoxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.)
(6) 2P4MZ: 2-phenyl-4-methylimidazole (manufactured by Shikoku Kasei Co., Ltd.)
(7) HX3741: microencapsulated catalyst containing an imidazole compound (manufactured by Asahi Ciba Co., Ltd.)
[0045]
[Table 3]
Figure 0003674675
* SO32H: Admatechs Co., Ltd. [0046]
【The invention's effect】
The underfill material for flip chip type semiconductor device of the present invention is excellent in thin film penetration and storage stability, and a semiconductor device using this underfill material is very reliable.
[Brief description of the drawings]
FIG. 1 is a schematic view showing an example of a flip-chip type semiconductor device.
FIG. 2 shows a test piece used in the penetration test, where (A) is a side view and (B) is a plan view.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Organic substrate 2 Bump 3 Semiconductor chip 4 Underfill material 5 Fillet material 11 Hot plate 12 Lower slide glass 13 Polyimide film 14 Upper slide glass 15 Gap 16 Epoxy resin composition

Claims (3)

（Ａ）液状エポキシ樹脂：１００重量部
（Ｂ）ポリオルガノシルセスキオキサン球状粒子を加熱燃焼させることにより得られる０．００５〜０．１重量％の表面残存炭素原子を有する球状シリカ：１００〜３００重量部
（Ｃ）硬化促進剤：０．０１〜１０重量部
を含有してなることを特徴とするフリップチップ型半導体装置用アンダーフィル材。(A) Liquid epoxy resin: 100 parts by weight (B) Spherical silica having 0.005-0.1% by weight surface residual carbon atoms obtained by heating and burning polyorganosilsesquioxane spherical particles: 100- 300 parts by weight (C) curing accelerator: 0.01 to 10 parts by weight An underfill material for a flip-chip type semiconductor device, comprising: （Ｂ）成分の球状シリカが、最大粒径が５０μｍ以下で、平均粒径が０．５〜１０μｍである請求項１記載のアンダーフィル材。Component (B) of the spherical silica is, the maximum particle size of 50μm or less, underfill material of claim 1, wherein an average particle diameter of 0.5 to 10 [mu] m. （Ｂ）成分の球状シリカ以外の無機質充填剤を含有し、（Ｂ）成分を含めた無機質充填剤全体に対する（Ｂ）成分の球状シリカの含有量が６０重量％以上である請求項１又は２記載のアンダーフィル材。  The inorganic filler other than the spherical silica as the component (B) is contained, and the content of the spherical silica as the component (B) with respect to the whole inorganic filler including the component (B) is 60% by weight or more. The underfill material described.
JP2000067640A 1999-03-17 2000-03-10 Underfill material for flip chip type semiconductor devices Expired - Fee Related JP3674675B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2000067640A JP3674675B2 (en) 1999-03-17 2000-03-10 Underfill material for flip chip type semiconductor devices

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP7137899 1999-03-17
JP11-71378 1999-03-17
JP2000067640A JP3674675B2 (en) 1999-03-17 2000-03-10 Underfill material for flip chip type semiconductor devices

Publications (2)

Publication Number Publication Date
JP2000327884A JP2000327884A (en) 2000-11-28
JP3674675B2 true JP3674675B2 (en) 2005-07-20

Family

ID=26412483

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2000067640A Expired - Fee Related JP3674675B2 (en) 1999-03-17 2000-03-10 Underfill material for flip chip type semiconductor devices

Country Status (1)

Country Link
JP (1) JP3674675B2 (en)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4583821B2 (en) * 2004-06-28 2010-11-17 新日鐵化学株式会社 Liquid epoxy resin composition
JP4737370B2 (en) * 2004-10-29 2011-07-27 セイコーエプソン株式会社 Manufacturing method of semiconductor device
JP2006216720A (en) 2005-02-02 2006-08-17 Sharp Corp Semiconductor device and its manufacturing method
US7405246B2 (en) * 2005-04-05 2008-07-29 Momentive Performance Materials Inc. Cure system, adhesive system, electronic device
JP2009049115A (en) * 2007-08-17 2009-03-05 Seiko Epson Corp Semiconductor device, and manufacturing method thereof
JP5577734B2 (en) * 2010-02-17 2014-08-27 日本電気株式会社 Electronic device and method for manufacturing electronic device
CN112457807A (en) * 2020-11-14 2021-03-09 烟台德邦科技股份有限公司 Preparation method of chip-level underfill material with excellent thermal stability

Also Published As

Publication number Publication date
JP2000327884A (en) 2000-11-28

Similar Documents

Publication Publication Date Title
KR100552877B1 (en) Sealing Materials for Flip Chip Semiconductor Devices and Flip Chip Semiconductor Devices
JP5354753B2 (en) Underfill material and semiconductor device
JP5502268B2 (en) Resin composition set for system-in-package semiconductor devices
US6225704B1 (en) Flip-chip type semiconductor device
JP5116152B2 (en) Resin composition for manufacturing semiconductor devices
US6376923B1 (en) Flip-chip type semiconductor device sealing material and flip-chip type semiconductor device
JP4066174B2 (en) Liquid epoxy resin composition, flip chip type semiconductor device and sealing method thereof
US6429238B1 (en) Flip-chip type semiconductor device sealing material and flip-chip type semiconductor device
JP3997422B2 (en) Liquid epoxy resin composition and semiconductor device
JP3773022B2 (en) Flip chip type semiconductor device
US6376100B1 (en) Flip-chip type semiconductor device underfill material and flip-chip type semiconductor device
JP3912515B2 (en) Liquid epoxy resin composition and semiconductor device
US6372839B1 (en) Flip-chip type semiconductor device underfill
JP3707531B2 (en) Flip chip type semiconductor device sealing material and flip chip type semiconductor device
JP3646785B2 (en) Underfill material for flip chip type semiconductor device and flip chip type semiconductor device
JP2009173744A (en) Underfill agent composition
JP3674675B2 (en) Underfill material for flip chip type semiconductor devices
JP2001055488A (en) Encapsulant for flip chip type semiconductor device and flip chip type semiconductor device
JP2010077234A (en) Liquid epoxy resin composition and semiconductor device
JP2010111747A (en) Underfill agent composition
JP5013536B2 (en) Underfill agent composition
JP4697476B2 (en) Liquid epoxy resin composition and flip chip type semiconductor device
JP5354721B2 (en) Underfill agent composition
JP2000273287A (en) Under-filling material for flip chip type semiconductor device and flip chip type semiconductor device
JP2005194502A (en) Liquid epoxy resin composition and semiconductor device

Legal Events

Date Code Title Description
A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20050111

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20050126

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20050314

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20050406

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20050419

R150 Certificate of patent or registration of utility model

Free format text: JAPANESE INTERMEDIATE CODE: R150

LAPS Cancellation because of no payment of annual fees