200915522 九、發明說明 【發明所屬之技術領域】 本發明係有關於積體電路封裝的領域。詳言 明係有關於電路板與積體電路晶粒上的接觸墊 pad )之間的線接合包封。 【先前技術】 製造於砂晶圓基材上的積體電路藉由線接合 接至印刷電路板上。線接合是非常薄的電線一 D 至4 0微米一其由接觸墊沿著晶圓基材的側邊延 電路板（PCB )上的接點。爲了保護及強化線接 合被密封在一被稱爲包封劑的環氧樹脂珠滴（be 從接觸墊到PCB的電線被作成比所需要的更長用 於PCB與接觸墊之間的間隙因爲熱膨脹，構件的 所產生的改變。這些比所需要的還長的電線很自 接觸墊與PCB之間的一個弧。該電線弧的頂端通 觸墊之上約300微米，但有些線接合會延伸得更 名稱讓人聯想到的，包封劑必需將整個電線的長 來，所以包封劑珠滴將擴展至接觸墊之上500微 微米。 製造於矽晶圓基材上的積體電路通常被稱f (d i e ) ’。爲了說明書的目的，晶粒一詞將被用 使用光刻技術（通常用於半導體製造中之蝕刻與 )製造於晶圓基材上的積體電路。如果該晶粒純 之，本發 (contact 而被電連 [徑約25 伸至印刷 合’線接 ad )內。 以適應介 屈曲等等 然地形成 常是在接 高。如其 度包封起 米至600 i 一 ‘晶粒 來指稱一 沉積技術 粹是一電 -5- 200915522 子的微處理器的話，就不太需要保持包封劑珠滴尺寸的嚴 密控制。然而，如果該晶粒是一具有有作用的上表面之微 機電系統（MEMS )裝置的話，則讓該晶粒的有作用的表 面與另一表面緊鄰就是有必要或是所想要的。此情況適用 於噴墨列印頭。列印媒介對噴嘴陣列的接近程度會影響列 印品質。相同地，如果一清潔表面刮掃過噴嘴的話，則包 封劑的珠滴會妨礙該刮掃接觸。 另一個問題是因爲包封劑珠滴的側邊不是筆直的而發 生。一種通常用來沉積該包封劑的技術包含將包封劑從一 針頭直接擠到一排線接合上。包封劑的體積及在晶粒上的 放置並沒有很精確。該幫浦壓力的變化或該針頭的速度上 稍微不一致都會造成該珠滴之與該有作用的表面相接觸的 一側被相當地彎曲。該珠滴的該側邊不是筆直的時，它必 需與該有作用的表面上之任何有作用的部件適當低間隔開 ’用以寬裕地適應擾亂（perturbation)。將電接點與該有 作用的表面的有作用的部分（例如，噴墨噴嘴）間隔開來 會耗盡有價値的晶圓資源並減少可從一片晶圓上製造出來 的晶粒數目。 有鑑於噴墨列印頭的廣泛使用，本發明將特別以在此 領域上的應用爲例來加以描述。然而，一般人將可瞭解的 是’這純粹者是舉例性的且本發明可同樣地應用到線接合 至一 PC B或其它支撐結構的積體電路上。 【發明內容】 -6- 200915522 依據第一態樣，本發明提供一種微處理器裝置，其包 含： 一支撐結構，其具有一晶片安裝區及一導體安裝區； 一被支撐在該晶片安裝區上的晶粒，該晶粒具有一與 該晶片安裝區接觸的背面及一與該背面相反之有作用的表 面，該有作用的表面具有電接觸墊； 多個電導體至少部分地被支撐在該導體安裝區上；及 一系列的線接合，其由該等電接觸墊延伸至多個被支 撐在該導體安裝區上的電導體；其中 該晶片安裝區相對於該導體安裝區被升高。 藉由將該晶片安裝區相對於該PCB的其它部分，或至 少連接至該線接合的PCB端的導體，升高，由該層形成的 弧的頂端更靠近該晶粒之有作用的表面。這可讓包封劑的 珠滴具有一相對於該有作用的表面而言較低的剖面。藉此 低的包封劑珠滴，該有作用的表面可被帶引更加緊鄰另一 表面而不相接觸。例如，在一列印頭1C上的噴嘴陣列可 以離該紙張路徑3 00微米至400微米。 較佳地，該晶片安裝區相對於該導體安裝區被升高超 過1 00微米。較佳地，該支撐結構具有一級階介於該晶片 安裝區與該導體安裝區之間。 較佳地，該等多個導體被一排沿著最靠近該晶粒的邊 緣之接合墊倂入到該可撓曲的印刷電路板（撓性PCB )中 ，該等接合墊離晶粒上的接觸墊超過2公釐。 較佳地，該等線接合是用直徑小於40微米的電線形 200915522 成的並延伸於該晶粒之有作用的表面上方小於100微米處 〇 較佳地，該等線接合被塑性地變形使得它們延伸於該 晶粒之有作用的表面上方小於5 0微米處。 較佳地，該有作用的表面具有功能性元件’其與該晶 粒上的接觸墊相距小於260微米。在一特佳的形式中，該 晶粒爲一噴墨列印頭1C且該等功能性元件爲噴嘴’墨水 經由噴嘴被噴出。在一些實施例中，該支撐結構爲一液晶 聚合物（LCP )模製物。 較佳地，該等線接合被覆蓋在一包封劑的珠滴中，該 包封劑的珠滴延伸於該晶粒之有作用的表面上方小於200 微米處。 較佳地，該等線接合被覆蓋在一包封劑的珠滴中，該 包封劑的珠滴具有一經過剖面化的表面，它是平的，平行 於該有作用的表面且與其相距小於1 0 0微米。 較佳地，該等線接合被覆蓋在一包封劑的珠滴中，該 包封劑的珠滴具有一平的且相對於該有作用的表面傾斜之 經過剖面化的表面。 較佳地，該等線接合被覆蓋在一包封劑的珠滴中，該 包封劑是一環氧樹脂物質，其在未固化時是搖溶性的（ thixotropic) 〇 較佳地，該等線接合被覆蓋在一包封劑的珠滴中，該 包封劑是一環氧樹脂物質，其在未固化時具有大於700cp 的黏度。 -8- 200915522 在一特定的實施例中，該列印頭1C被安裝在一印表 機內使得在使用期間噴嘴離紙張路徑小於100微米。 依據第二態樣，本發明提供一種將介於一晶粒上的接 觸墊與一支撐結構上的導體之間的線接合剖面化作業的方 法，該方法包含的步驟爲： 用一線接合將晶粒上的接觸墊電連接至該支撐結構上 的導體，該線接合延伸成爲一從該接觸墊至該導體的弧； 推擠該線接合用以讓該弧塌陷並將該線接合塑性地變 形；及 釋放該線接合使得該塑性變形將該線接合保持在一較 平的剖面形狀。 該線接合的強度是相當小，在3至5克力的等級。然 而，申請人的硏究顯示該線接合結構堅固到足以承受來自 塑性變形之一定程度的加工硬化。該線接合的弧可在不犧 牲與PCB的電連接下被變形成爲一較平的剖面。 較佳地，該晶粒具有一有作用的表面其具有功能性元 件，接觸墊其被形成在該有作用的表面的一個邊緣上，該 線接合具有一小於40微米的直徑且該弧延伸在該晶粒之 有作用的表面上方大於100微米處。 較佳地，該等線接合被塑性地變形使得它們延伸於該 晶粒之有作用的表面上方小於5 0微米處。 較佳地，該線接合藉由與一刀片狀物嚙合而被推擠， 該刀片狀物具有一用來接觸該線接合之圓角化的邊緣區。 較佳地，該方法進一步包含的步驟爲： -9- 200915522 施用一包封劑的珠滴於該線接合上；及 移動一剖面化作業表面於該有作用的表面之上用以將 該包封劑的珠滴平坦化。 較佳地，該包封劑的珠滴具有一經過剖面化的表面， 它是平的，平行於該有作用的表面且與其相距小於100微 米。 較佳地，該包封劑的珠滴具有一平的且相對於該有作 用的表面傾斜之經過剖面化的表面。 較佳地，該包封劑是一環氧樹脂物質，其在未固化時 具有大於7 〇 〇 C P的黏度。在一較佳的實施例中’該包封劑 是一環氧樹脂物質，其在未固化時是搖溶性的（ thixotropic) 。 較佳地，該方法進一步包含的步驟爲： 將該剖面化作業表面放置成與該有作用的表面相鄰並 與其間隔開，用以界定一間隙；及 將包封劑的珠滴施用到該等接觸墊上，使得該珠滴的 一側接觸該剖面化作業表面且該珠滴的一部分延伸至該間 隙內並到達該有作用的表面。 較佳地，該有作用的表面具有功能性元件’其與該晶 粒上的接觸墊相距小於2 6 0微米。在一特佳的形式中’該 晶粒爲一噴墨列印頭IC且該等功能性元件爲噴嘴’墨水 經由噴嘴被噴出。在一些實施例中’該列印頭IC被安裝 在一印表機內使得在使用期間噴嘴離紙張路徑小於100微 米。 -10- 200915522 較佳地’該支撐結構’其具有一晶片安裝區及一導體 安裝區，該晶粒被支撐在該晶片安裝區上，及多個電導體 至少部分地被支撐在該導體安裝區上，其中該晶片安裝區 相對於該導體安裝區被升高。 較佳地，該晶片安裝區相對於該導體安裝區被升高超 過1 0 0微米。較佳地，該支撐結構具有一級階介於該晶片 安裝區與該導體安裝區之間。在一些實施例中，該等多個 導體被一排沿著最靠近該晶粒的邊緣之接合墊倂入到該可 撓曲的印刷電路板（撓性p c B )中，該等接合墊離晶粒上 的接觸墊超過2公釐。 較佳地，該支撐結構爲一液晶聚合物（LCP )模製物 〇 依據第三態樣，本發明提供一種將沿著安裝在一支撐 結構上的晶粒的邊緣延伸之包封劑的珠滴剖面化作業的方 法，該方法包含的步驟爲： 沿著該晶粒的邊緣將包封劑的珠滴沉積在線接合上； 將一剖面化作業表面放置在該晶粒之上離該晶粒一預 定間距處， 在該包封劑的珠滴固化之前將該剖面化作業表面移動 橫過該珠滴，用以重塑該珠滴的剖面；及 固化該包封劑的珠滴。 本發明發現，該包封劑可在不從線接合上剝除該包封 劑之下被被一剖面化作業表面有效地形塑。該包封劑珠滴 之正常的外凸形上表面可被該剖面化作業表面推向—側。 -11 - 200915522 藉由此低的包封劑珠滴，該有作用的表面可被帶引更加緊 鄰另一表面而不相接觸。例如，在一列印頭IC上的噴嘴 陣列可以離該紙張路徑3 00微米至400微米。藉由在施加 一包封劑並對其剖面化作業之前將線接合弧塌陷或平坦化 ，在該列印頭1C上的噴嘴陣列可以離該紙張路徑不到1 〇〇 微米。 較佳地，該等線接合延伸成一從該晶粒之各別的接觸 墊到該支撐結構上之對應的導體之弧且該方法包含的步驟 爲： 推擠該線接合用以將該線接合塑性地變形；及 釋放該線接合使得該塑性變形將該線接合保持在一較 平的剖面形狀。 較佳地，該晶粒具有一有作用的表面其具有功能性元 件，接觸墊其被形成在該有作用的表面的一個邊緣上，該 線接合具有一小於40微米的直徑且該弧延伸在該晶粒之 有作用的表面上方大於100微米處。 較佳地，該等線接合被塑性地變形使得它們延伸於該 晶粒之有作用的表面上方小於5 0微米處。 較佳地，該線接合藉由與一刀片狀物嚙合而被推擠， 該刀片狀物具有一用來接觸該線接合之圓角化的邊緣區。 較佳地，該包封劑的珠滴具有一經過剖面化的表面， 它是平的，平行於該有作用的表面且與其相距小於1 〇 〇微 米° 較佳地，該包封劑的珠滴具有一平的且相對於該有作 -12- 200915522 用的表面傾斜之經過剖面化的表面° 較佳地，該包封劑是一環氧樹脂物質未 具有大於700cp的黏度。 較佳地，該包封劑是一環氧樹脂物質’ ##未 是搖溶性的（t h i X 〇 t r 〇 p i c )。 較佳地，該方法進一步包含的步,驟爲· 將該剖面化作業表面放置成與該有作$ @ ^ ® 與其間隔開，用以界定一間隙；及 將包封劑的珠滴施用到該等接觸墊上’丨吏彳辱^ 一側接觸該剖面化作業表面且該珠滴的一 $ # M # 隙內並到達該有作用的表面。 較佳地，該有作用的表面具有功能性元1 {牛’ # 粒上的接觸墊相距小於260微米。在一更佳的形式 晶粒爲一噴墨列印頭1C且該等功能性元件爲噴嘴 經由噴嘴被噴出。在一些實施例中，該列印頭IC 在一印表機內使得在使用期間噴嘴離紙張路徑小於 米。 較佳地，該支撐結構，其具有一晶片安裝區及 安裝區，該晶粒被支撐在該晶片安裝區上’及多個 至少部分地被支撐在該導體安裝區上，其中該晶片 相對於該導體安裝區被升高。 較佳地，該晶片安裝區相對於該導體安裝區被 過1 〇〇微米。在一特佳的實施例中，該支撐結構具 階介於該晶片安裝區與該導體安裝區之間。 固化時 固化時 相鄰並 珠滴的 至該間 與該晶 中，該 '墨水 被安裝 100微 一導體 電導體 安裝區 升高超 有一級 -13- 200915522 較佳地’該等多個導體被一排沿著最靠近該晶粒的邊 緣之接合墊倂入到一可撓曲的印刷電路板（撓性p c B )中 ’該等接合墊離晶粒上的接觸墊超過2公釐。 較佳地，該支撐結構爲一液晶聚合物（L C P )模製物 〇 依據第四態樣，本發明提供一種將包封劑施用於一安 裝在一支撐基材上的晶粒上的方法，該方法包含的步驟爲 提供一安裝在一支撐基材上的晶粒，該晶粒具有一與 該支撐結構接觸的背面及一與該背面相反之有作用的表面 ，該有作用的表面具有電接觸墊； 將一阻障物放置在鄰近該等電接觸墊處且與該有作用 的表面間隔開用以界定一間隙及；及 沉積一珠滴的包封劑於該等電接觸墊上使得該等珠滴 的一側接觸該阻障物且該珠滴的一部分延伸至該間隙中並 到達該有作用的表面上。 將一阻障物放置在該有作用的表面上使得它界定一窄 的間距讓該包封劑前端（介於該包封劑與該有作用的表面 之間的接觸線）的形狀能夠被更嚴密地被控制。來自針頭 之包封劑的任何流速上的變化會造成在珠滴及/或珠滴的 PCB側在高度上的壟起或凹陷。介於該阻障物與該有作用 的表面之間的間隙所產生之流體阻力係指流入該間隙及流 到該有作用的表面上的的包封劑量幾乎是固定的。減小的 流動變化讓該包封劑前端緊密地對應該阻障物的形狀。更 -14 - 200915522 大的包封劑前端控制讓該晶粒之有作用的表面上的功能性 元件能夠更靠近接觸墊。 較佳地，該阻障物爲一剖面化作業表面且該方法進一 步包含的步驟爲： 將該剖面化作業表面移動於該有作用的表面上方，用 以將包封劑的珠滴平坦化。 較佳地，該方法進一步包含的步驟爲： 在沉積該包封劑的珠滴之前，用線接合將該晶粒上的 接觸墊電連接至該支撐基材上各別的導體，該等線接合每 一者都延伸一從該接觸墊到該導體的弧； 推擠該線接合用以讓該弧塌陷並將該線接合塑性地變 形；及 釋放該線接合使得該塑性變形將該線接合保持在一較 平的剖面形狀。 在一更佳的形式中，該有作用的表面其具有功能性元 件，接觸墊其被形成在該有作用的表面的一個邊緣上，該 線接合具有一小於40微米的直徑且該弧延伸在該晶粒之 有作用的表面上方大於100微米處。 較佳地，該線接合被塑性地變形使得它們延伸於該晶 粒之有作用的表面上方小於50微米處。在另一較佳的形 式中，該線接合藉由與一刀片狀物嚙合而被推擠，該刀片 狀物具有一用來接觸該線接合之圓角化的邊緣區。 較佳地，該包封劑的珠滴具有一經過剖面化的表面， 它是平的，平行於該有作用的表面且與其相距小於1 〇〇微 -15- 200915522 米。 較佳地，該包封劑的珠滴具有一平的且相對於該有作 用的表面傾斜之經過剖面化的表面。 較佳地，該包封劑是一環氧樹脂物質，其在未固化時 具有大於7〇〇cp的黏度。 較佳地，該包封劑是一環氧樹脂物質，其在未固化時 是搖溶性的（thixotropic) ° 較佳地，該有作用的表面具有功能性元件，其與該晶 粒上的接觸墊相距小於260微米。在一特佳的形式中，該 晶粒爲一噴墨列印頭1C且該等功能性元件爲噴嘴，墨水 經由噴嘴被噴出。較佳地，該列印頭1C被安裝在一印表 機內使得在使用期間噴嘴離紙張路徑小於1 〇 〇微米。 較佳地，該支撐結構具有一晶片安裝區及一導體安裝 區，該晶粒被支撐在該晶片安裝區上，及多個電導體至少 部分地被支撐在該導體安裝區上’其中該晶片安裝區相對 於該導體安裝區被升高。在一特佳的形式中’該晶片安裝 區相對於該導體安裝區被升高超過100微米。在較佳的實 施例中，該支撐結構具有一級階介於該晶片安裝區與該導 體安裝區之間。在特佳的實施例中’該等多個導體被一排 沿著最靠近該晶粒的邊緣之接合墊倂入到一可撓曲的印刷 電路板（撓性p c B )中’該等接合墊離晶粒上的接觸墊超 過2公釐。 較佳地，該支撐結構爲一液晶聚合物（LCP)模製物 -16- 200915522 依據第五態樣，本發明提供一種施用包封劑至介於一 晶粒與一支撐基材上的導體之間的線接合上的方法，該方 法包含的步驟爲： 形成該包封劑的珠滴於一剖面化作業表面上； 放置該剖面化作業表面使得該珠滴接觸該晶粒；及 相對於該晶粒移動該剖面化作業表面，用以用該包封 劑覆蓋該等線接合。 用一剖面化作業表面將包封劑刮掃過該等線接合可提 供該包封劑前端的控制以及該包封劑相對於該晶粒的高度 的控制。該剖面化作業表面相對於該晶粒的運動可被嚴密 地控制用以將包封劑形塑成所想要的形事。使用一列印頭 晶粒的例子，該包封劑可被形塑用以呈現一從該噴嘴表面 升高該等線接合之上的一高點之傾斜面。這可被列印頭維 修所利用，藉以便於維持固定的接觸壓力於該刮掃機構上 。這藉由參照圖式在下文中進一步說明。然而，將可被瞭 解的是，該包封劑可藉由使用特定形狀的剖面化作業表面 及詳對於該晶粒的運動來形塑用以具有凸脊，邊溝，溝槽 等等。 較佳地’該方法進一步包含的步驟爲： 將該剖面化作業表面浸泡在該包封劑物質的容器內用 以形成一包封劑的珠滴於該剖面化作業表面上。 選擇上地’該剖面化作業表面爲一具有筆直邊緣的刀 片狀物且該方法進一步包含的步驟爲： 將該刀片狀物定向（orienting)使得該筆直的邊緣是 -17- 200915522 最低的邊緣及將該筆直的邊緣浸泡在該包封劑物質中用以 沿著該筆直的邊緣形成該包封劑的珠滴。 較佳地’該晶粒具有一帶有功能性元件之有作用的表 面及多個沿著一邊緣被形成的接觸墊用以與該等線接合接 觸，使得該等線接合延伸成爲一從該等接觸墊分別到達每 一導體的弧，該等線接合具有一小於40微米的直徑及該 弧延伸在該晶粒之有足用的表面上方高於100微米處。 較佳地，該方法進一步包含的步驟爲： 在包封之前，推擠該線接合用以讓該弧塌陷並將該線 接合塑性地變形；及 釋放該線接合使得該塑性變形將該線接合保持在一較 平的剖面形狀。 較佳地，該等線接合被塑性地變形使得它們延伸於該 晶粒之有作用的表面上方小於5 0微米處。較佳地，該線 接合藉由與一刀片狀物嚙合而被推擠，該刀片狀物具有一 用來接觸該線接合之圓角化的邊緣區。 較佳地，覆蓋該等線接合之包封劑具有一經過剖面化 的表面，它是平的，平行於該有作用的表面且與其相距小 於100微米。 較佳地，該包封劑的珠滴具有一平的且相對於該有作 用的表面傾斜之經過剖面化的表面。 較佳地，該包封劑是一環氧樹脂物質，其在未固化時 具有大於700cp的黏度。 較佳地，該包封劑是一環氧樹脂物質，其在未固化時 -18- 200915522 是搖溶性的（thixotropic )。較佳地，該等功能性元件與 該晶粒上的接觸墊相距小於2 6 0微米。在一更佳的形式中 ，該晶粒爲一噴墨列印頭1C且該等功能性元件爲噴嘴， 墨水經由噴嘴被噴出。選擇上地，該列印頭IC被安裝在 一印表機內使得在使用期間噴嘴離紙張路徑小於1 〇 〇微米 〇 較佳地，該支撐結構具有一晶片安裝區及一導體安裝 區，該晶粒被支撐在該晶片安裝區上’及多個電導體至少 部分地被支撐在該導體安裝區上，其中該晶片安裝區相對 於該導體安裝區被升高。在一特佳的形式中，該晶片安裝 區相對於該導體安裝區被升高超過100微米。在另一較佳 的形式中，該支撐結構具有一級階介於該晶片安裝區與該 導體安裝區之間。在一較佳的實施例中，該等多個導體被 一排沿著最靠近該晶粒的邊緣之接合墊倂入到一可撓曲的 印刷電路板（撓性PCB )中，該等接合墊離晶粒上的接觸 墊超過2公釐。較佳地，該支撐結構爲一液晶聚合物（ LCP )模製物。 【實施方式】 圖1顯示用來施用一包封劑珠滴至線接合上之一般的 技術。一晶粒4被安裝到一支撑結構 6上鄰近一撓性 PCB 8 (可撓曲的印刷電路板）的邊緣處。該晶粒4具有一 排接觸墊1 0沿著一個邊緣且該撓性PCB 8具有對應的接 合墊1 2。線接合1 6從接觸墊1 0延伸至接合墊1 2。電力 -19- 200915522 及資料經由該撓性PCB 8內的導電跡線14被傳送至晶粒 4。這是安裝在許多電子裝內之晶粒的簡化代表。安裝在 LCP (液晶聚合物）模製物上用來接受來自一鄰近的撓性 PCB，如美國專利申請案第...號（我們的文件編號 RRC001US )中所描述的，其藉由此參照被倂於本文中， 的該列印頭1C晶粒爲此類晶粒安裝構造的一個例子。一 般的從業人員將可瞭解的是，該晶粒可以被直接安裝在一 其上形成有導線之硬式PCB上。 線接合16被覆蓋在一包封劑2的珠滴內用以保護並 補強該等線接合。該包封劑2從一排出針頭1 8直接施用 至線接合1 6上。通常該包封劑珠滴2是三個分開的珠 滴一兩個被稱爲‘水壩（dam) ’的包封劑20，及一個被稱 爲‘裝塡物（fill )’的包封劑22。水壩包封劑20的黏度高 於裝塡物包封劑22的黏度，且水壩包封劑20用來形成一 渠道用來容納該裝塡物包封劑珠滴。在該晶粒4上方的該 珠滴2的高度Η通常約500-600微米。在大多數的電子裝 置中，這並不會產生問題。然而，如果該晶粒具有一有作 用的表面其必需與另一表面以極接近的方式工作的化，此 珠滴將會是一個障礙。 將該晶粒相對於該撓性PCB升高 圖2顯示一級階式支撐結構6其將該晶片安裝區26 相對於該PCB安裝區24 (或至少是安裝PCB接合墊12的 區域）升高。藉著晶粒4在該升高的晶片安裝區26上， -20- 200915522 線接合1 6的弧相對於晶粒4之有作用的表面28較低。事 實上，線接合1 6之附著於接觸墊1 0的端部可以是該弧的 頂點（應記住的是該線接合弧是用來適應晶粒與PCB的某 些相對運動）。當線接合1 6被包封劑2覆蓋住時，該珠 滴具有一在該晶粒4之有作用的表面28上方之減小的高 度H。如果該包封劑珠滴2使用兩個水壩包封劑20及一 個裝塡物包封劑22的話，則這些珠滴的位置，體積及黏 度必需將該級階考慮進去。小於1 〇〇微米的珠滴高度是可 輕易地達成，且藉由額外的手段，譬如像是線弧塌陷及珠 滴剖面化作業（將於下文中討論），可達成小於50微米 的珠滴高度。 藉著晶粒4被升高至該撓性PCB 8之上4 1 0微米，線 接合1 6的高度在該晶粒之上約3 4微米。藉著該晶粒被升 高至該撓性PC B 8之上610微米，線接合約爲20微米。 進一步再升高該晶粒對於級階7 1 0微米的線接合高度（約 爲20微米）僅有微小或沒有進一步降低。 用一剖面作業刀片狀物來形塑該包封劑珠滴 圖3 A至3 C顯示該包封劑2被用一剖面作業刀片狀物 3 0加以剖面作業。該支撐結構6再次被級階化用以減小線 接合16在該晶粒4之上的高度。在該環氧樹脂包封劑2 固化之前，該剖面作業刀片狀物3 0在一預定的路徑上移 動橫過該晶粒4與線接合。如圖3 B所不，刀片狀物3 0將 珠滴的頂部移至其撓曲PCB側用以形成一平坦的頂面32 -21 - 200915522 ，其位在該晶粒4之上顯著減小的高度Η處。 該包封劑珠滴2如圖1及2所示地可以多個分開的珠 滴，或可以是一種物質的單一珠滴。然而，爲了要該經過 剖面作業化之包封劑的更嚴密的尺寸控制，所用之包封劑 應是搖溶性的（thixotropic )，當從該排出針頭被沉積之 後，或被該刀片狀物3 0剖面化之後，該物質不應因其本 身的重量而流動，而應維持其形狀直到它固化爲止。這需 要該環氧樹脂具有一大於約7〇〇cp之未固化的黏度。一適 合的包封劑爲由 Dymax公司所製造的 DYMAX 900 1 -E-v 3.1晶片包封劑，其在未固化時具有約800 cp的黏度。該 刀片狀物30可以是陶瓷（玻璃）或金屬且較佳地約200 微米厚。 將可被瞭解的是，該刀片狀物與3 0與晶粒4的相對 運動可被精確地控制。這可讓該高度Η由線接合處理的公 差來決定。只要Η大於在該晶粒之上之線接合弧的標稱高 度加上最大公差，包封劑2將可覆蓋並保護線接合1 6。藉 此技術，高度Η可輕易地從5 0 0 - 6 0 0微米被減小至小於 3〇〇微米。如果線接合弧的高度亦被減小的話，該包封劑 珠滴的高度可小於1 〇〇微米。本案申請人使用此技術來將 列印頭晶粒上的包封劑剖面化使其在低點的高度低至50 微米。如圖3 C所示，該最低點是位在該包封劑前端且該 刀片狀物3 0在珠滴2的頂部形成一傾斜面3 2。該傾斜面 可在從噴嘴面上清除掉紙張灰麈與乾掉的墨水時被列印頭 維修系統所利用。這顯示出此技術的能力不僅僅可減小該 -22- 200915522 包封劑珠滴的高度’還可以形成一實施包封線接合之外的 其它功能的表面。該刀片狀物的邊緣剖面及該刀片狀物相 對於該晶粒的路徑可被構建來形成一表面，其具有用於各 種目地的各式形狀。 線接合弧的塑性變形 圖4A至4C顯示用於降低線接合的剖面的另一種技術 。圖4A顯示透過線接合1 6連接至撓性PCB 8的晶粒4。 雖然該級階式支撐結構6已相較於平的支撐結構將線接合 弧的高度降低，但線接合仍具有一向上彎曲的自然傾向， 而不是向下朝向該級階的角落。線接合1 6的直徑典型地 約32微米且具有約3至5克力的拉力。該拉力爲破弄斷 與接觸墊10或接合墊12的連接所需的拉力負荷。由於這 些結構的脆弱性（其中的一個原因是施用包封劑），所以 傳統上的智慧是避免線接合弧與其它實心表面接觸。 如圖4B所示，線接合16的弧可被線推壓件34弄坍 塌。該線推壓件3 4推移線該接合1 6使其足以將該弧彈性 地及塑性地變形。本案申請人已展示與該線推壓件3 4接 觸會造成在該電線上之決部化的加工硬化，但只要該力量 沒有過大，它就不會斷裂。該線推壓件34的端部被圓角 化用以避免應力集中點。此線推壓件34可以是一用來與 單一線接合相接觸的尖筆（stylus )或是用來同時推壓多 個線接合的刀片狀物。 現參照圖4 C，該線推壓件3 4被縮回且該電線朝向其 -23- 200915522 原來的形狀回彈用以解除該彈性變形。然而，該塑性變形 仍繼續存在且在該晶粒4之上的線接合高度被大幅地減小 。試驗顯示使用此技術可讓一最初爲2 0 0微米的線接合環 圈高度被減小至約4 5微米。試驗亦顯示被塑性變形的電 線的拉扯強度仍保持在約3至5克力。 線接合的塌陷是未被控制的且讓線接合有點被隨機地 變形。然而’將線接合推移更靠近該晶粒可提供被更一致 地形塑之坍蹋的線接合。本案申請人的硏究顯示對於該晶 粒而言接觸200至300微米的電線可提供最佳的結果。 如圖4 D所示’晶粒4與撓性P C B 8被安裝在一平的 支撐結構6上。如上文中討論的，這表示該線接合弧的最 初環圏高度是高出許多的一約在該晶粒4之上約400微米 。因此，在該環圏被該線推壓件推壓坍禝時該電線具有更 多的塑性變形。即便如此，本案申請人的結果顯示，在推 壓之後之剩餘的環圈高度約爲20-50微米。 圖5A及5B顯示被一包封劑珠滴2所覆蓋之坍榻的線 接合1 6。即使是在固化之前沒有珠滴剖面化作業，該珠滴 在該晶粒之上的高度Η仍遠小於該珠滴包封原始之未變形 的電線環圈所需的高度。 用剖面化作業刀片狀物施用包封劑 圖6Α，6Β及6C顯示使用該剖面化作業刀片狀物30 代替一排出針頭（參見圖1及2 )來施用包封劑珠滴。如 先前討論過的，來自該排出針頭的包封劑流速會改變且這 -24- 200915522 對於包封劑前端在晶粒4之有作用的表面上的位置會產生 大的變化。因此，在晶粒4之有作用的表面上的任何功能 性元件都必需與接觸墊1 0充分地間隔開用以容許緩丨曼而 曲折地前進的包封劑前端。 用剖面化作業刀片狀物施用包封劑可避免來自該排出 針頭的流速波動所造成的問題。如圖6A所示’該包封劑 珠滴4 0可單純地藉由將該剖面化作業刀片狀物3 0浸泡至 一未固化的包封劑環氧樹脂的容器內而被形成在該剖面化 作業刀片狀物30上。當然，該珠滴40亦可藉由其它的傳 統方式，譬如將該排出針頭沿著該刀片狀物3 〇的一端移 動，來形成。 圖6B顯示該刀片狀物30已被降低用以將該珠滴40 接觸到該晶粒4上。當該包封劑物質接觸該晶粒表面時， 它沿著該表面濕潤，同時保持被該刀片狀物的邊緣壓住。 該刀片狀物30被保持在該晶粒4之上一預定的高度且被 移動橫過該珠滴2用以將該珠滴平坦化及降低其剖面。被 該刀片狀物3 0從該珠滴的頂端移位的包封劑被散佈在該 珠滴2的PCB側上。該包封劑是否比所必要更散佈於該 PCB上是無關緊要的。只要線接合16與接合墊12被覆蓋 及可，任何額外的包封劑在該PCB 8表面上都不會是有害 的。 在圖6 C中，線接合1 6高度已藉由依據上述的技術將 該電線弧塌陷來加以降低。如之前討論過的，被該排出針 頭所放置的珠滴2不需要大到能夠覆蓋住該線接合1 6坍 -25- 200915522 塌時的大小。再者，當對該包封劑2實施剖面化作 該刀片狀物3 0可更靠近該晶粒4而不與線接合1 6 因此，在圖6 C中的珠滴剖面比圖6 B中的珠滴剖面 低。 包封劑前端控制 當該包封劑物質從該排出針頭被施用時’在流速 微小變化會造成珠滴在較大流量的位置點處壟起。因 該珠滴之與該晶粒之有作用的表面接觸的一側不是筆 ，而是有顯著的擾亂（perturbation)。這些擾亂必需 容納在接觸墊與該有作用的表面上之任何功能性元件 。介於接觸墊與功能性元件之間的間距會使用掉有價 ‘晶片不動產（chip real estate) ’。本案申S靑人之則 發出在接觸墊與第一排噴嘴之間有260微米的間距的 頭晶粒。更佳的包封劑前端控制可減小接點與作業元 間的間距，以及晶粒的整體尺寸。因此，此設計可更 巧且從原始的晶圓片上可作出更多的晶片。 如圖7 A及7 B所示，該剖面化作業刀片狀物3 0 來控制包封劑珠滴2的前端3 6。該刀片狀物3 0被放 該晶粒4之上用以在其下緣與該有作用的表面28之 定一間隙42。當該排出針頭1 8排出出該包封劑物質 ，其流動在該有作用的表面上，該刀片狀物的一側與 質帶（material fillet)延展通過該間隙42。由於該 所產生之流動阻力的關係，所以流量變動對於流經該 時， 觸。 來得 上的 此， 直的 要被 之間 値的 已開 列印 件之 加精 被用 置在 間界 44時 該物 間隙 間隙 -26- 200915522 的物質帶的尺寸只有很小的影響。因此’該包封劑前端3 6 很接近地符合該刀片狀物3 〇的下緣的線。 如圖7B所示，該剖面化作業刀片狀物3 0在該包封劑 珠滴2從該排出針頭被排出來時就已經在定位上要對該包 封劑珠滴實施剖面化作業。該刀片狀物3 0單純地只是在 一遠離噴嘴38的方向上移動於該晶粒4的上方。這可將 該包封劑前端3 6保持在定位並將線接合1 6上放之包封劑 珠滴2的剖面平坦化。 本發明已在本文中以舉例的方式加以描述。熟習此技 藝者將可輕易地認知到許多未偏離本發明之廣意的發明性 槪念的精神與範圍的變化與修改。 【圖式簡單說明】 本發明的實施例現將以舉例的方式參照附圖加以描述 ，其中： 圖1爲用來施用一珠滴的封包劑於線接合上之一般先 前技藝技術的示意代表圖； 圖2爲安裝於一支撐結構上之晶粒的示意代表圖，該 支撐結構具有相對於該撓性PCB安裝區被升高的晶片安裝 ， 圖3 A，3 B及3 C爲該包封劑珠滴藉由使用一活動的 刀片狀物而被剖面化成爲一所想要的形狀之示意代表圖； 圖4 A至4 D爲被塑性便形剖面化的線接合的示意代 表圖； -27- 200915522 圖5 A及5 B顯示被塑性變形之線接合之包封劑珠滴高 度的減小； 圖6A至6C顯示該包封劑珠滴藉由使用該剖面化作業 的刀片狀物而被施加至線接合；及 圖7A及7B顯示被用來控制該晶粒的表面上的包封劑 珠滴的剖面化作業刀片狀物。 【主要元件符號說明】 4 :晶粒 6 :支撐結構 8 :撓性P C B 10 :接觸墊 12 :接合墊 1 4 :導電跡線 1 6 :線接合 1 8 :排出針頭 2 :包封劑，珠滴 2 0 :水壩包封劑 22 :裝塡包封劑 24 : PCB安裝區 2 ό ·晶片安裝區 28 :有作用的表面 3 〇 :剖面化作業刀片狀物 3 2 :平坦的頂面，傾斜面 -28- 200915522 34 :線 40 :包 36 :包 42 :間 44 :包 38 :噴 推壓件 封劑珠滴 封劑前端 隙 封劑物質 嘴 -29200915522 IX. Description of the Invention [Technical Field of the Invention] The present invention relates to the field of integrated circuit packaging. The detailed description relates to the wire bond encapsulation between the board and the pad pad on the integrated circuit die. [Prior Art] An integrated circuit fabricated on a sand wafer substrate is bonded to a printed circuit board by wires. The wire bond is a very thin wire - D to 40 microns - a contact on the board (PCB) from the side of the wafer substrate by the contact pads. In order to protect and strengthen the wire bond is sealed in an epoxy droplet called an encapsulant (be the wire from the contact pad to the PCB is made longer than needed for the gap between the PCB and the contact pad because Thermal expansion, the resulting change in the components. These longer wires than required are from an arc between the contact pad and the PCB. The top of the wire arc is about 300 microns above the contact pad, but some wire bonds will extend. The name is reminiscent of the encapsulant, which must extend the length of the entire wire, so the encapsulant beads will extend to 500 micrometers above the contact pad. The integrated circuit fabricated on the germanium wafer substrate is usually It is called f (die). For the purposes of this specification, the term die will be used to fabricate an integrated circuit on a wafer substrate using photolithography (usually used in etching in semiconductor fabrication). Pure grain, the hair (contact is connected to the electric connection [about 25 to the print joint] line). In order to adapt to the buckling, the formation is often in the high. If the degree is up to 600 i a 'grain to refer to a deposition technique is If the microprocessor is a sub-microprocessor, it is not necessary to maintain tight control of the size of the encapsulant bead. However, if the die is a microelectromechanical system (MEMS) device with a functional upper surface, It is necessary or desirable to have the active surface of the die in close proximity to the other surface. This applies to inkjet printheads. The proximity of the print media to the nozzle array can affect print quality. Similarly, if a cleaning surface is swept across the nozzle, the beads of the encapsulant will interfere with the wiping contact. Another problem is that the sides of the encapsulant bead are not straight. The technique for depositing the encapsulant involves extruding the encapsulant directly from a needle to a row of wire bonds. The volume of the encapsulant and the placement on the die are not very precise. The change in the pressure of the pump or the A slight inconsistency in the speed of the needle causes the side of the bead that is in contact with the active surface to be substantially curved. When the side of the bead is not straight, it must be on the active surface. Ren The active components are suitably spaced low to adequately accommodate the perturbation. Separating the electrical contacts from the active portions of the active surface (eg, inkjet nozzles) can deplete valuable enthalpy Wafer resources and reduce the number of dies that can be fabricated from a wafer. In view of the widespread use of inkjet printheads, the present invention will be described, inter alia, as an application in this field. However, the average person will It can be understood that 'this is purely exemplary and the invention can be equally applied to an integrated circuit that is wire bonded to a PC B or other support structure. [Abstract] -6- 200915522 According to the first aspect, The present invention provides a microprocessor device comprising: a support structure having a wafer mounting region and a conductor mounting region; a die supported on the wafer mounting region, the die having a die mounted to the die a back surface of the region contact and an active surface opposite the back surface, the active surface having an electrical contact pad; the plurality of electrical conductors being at least partially supported on the conductor mounting region; A series of wire bonds extending from the electrical contact pads to a plurality of electrical conductors supported on the conductor mounting region; wherein the wafer mounting region is raised relative to the conductor mounting region. By raising the wafer mounting area relative to other portions of the PCB, or at least the conductors of the PCB-bonded PCB ends, the top end of the arc formed by the layer is closer to the active surface of the die. This allows the bead of the encapsulant to have a lower profile relative to the active surface. With this low encapsulant bead, the active surface can be brought closer to the other surface without contact. For example, the array of nozzles on a column of print heads 1C can be from 300 microns to 400 microns from the paper path. Preferably, the wafer mounting area is raised by more than 100 microns relative to the conductor mounting area. Preferably, the support structure has a first order between the wafer mounting area and the conductor mounting area. Preferably, the plurality of conductors are inserted into the flexible printed circuit board (flexible PCB) by a row of bond pads closest to the edge of the die, the bond pads being separated from the die The contact pads are over 2 mm. Preferably, the wire bonds are formed by a wire shape 200915522 having a diameter of less than 40 microns and extending over the active surface of the die by less than 100 microns. Preferably, the wire bonds are plastically deformed such that They extend less than 50 microns above the active surface of the die. Preferably, the active surface has a functional element 'which is less than 260 microns from the contact pads on the crystal. In a particularly preferred form, the die is an ink jet print head 1C and the functional elements are nozzles' ink is ejected through the nozzles. In some embodiments, the support structure is a liquid crystal polymer (LCP) molding. Preferably, the wire bonds are covered in a bead of an encapsulant, the beads of the encapsulant extending less than 200 microns above the active surface of the die. Preferably, the wire bonds are covered in a bead of an encapsulant, the bead of the encapsulant having a profiled surface which is flat, parallel to and spaced from the active surface Less than 1000 microns. Preferably, the wire bonds are covered in a bead of an encapsulant having a flat, profiled surface that is inclined relative to the active surface. Preferably, the wire bonds are covered in a bead of an encapsulant which is an epoxy material which is thixotropic when uncured. Preferably, such The wire bond is covered in a bead of an encapsulant which is an epoxy material having a viscosity of greater than 700 cp when uncured. -8- 200915522 In a particular embodiment, the printhead 1C is mounted in a printer such that the nozzles are less than 100 microns from the paper path during use. According to a second aspect, the present invention provides a method of wire bonding profile work between a contact pad on a die and a conductor on a support structure, the method comprising the steps of: bonding the wire with a wire bond a contact pad on the granule electrically connected to the conductor on the support structure, the wire bond extending into an arc from the contact pad to the conductor; pushing the wire bond to collapse the arc and plastically deform the wire bond And releasing the wire bond such that the plastic deformation maintains the wire bond in a relatively flat cross-sectional shape. The strength of the wire joint is quite small, on the order of 3 to 5 grams force. However, Applicants' investigations have shown that the wire joint structure is strong enough to withstand a certain degree of work hardening from plastic deformation. The wire-engaging arc can be deformed into a flat profile without sacrificing electrical connection to the PCB. Preferably, the die has a functional surface having a functional element, the contact pad being formed on an edge of the active surface, the wire bond having a diameter of less than 40 microns and the arc extending Above the active surface of the die is greater than 100 microns. Preferably, the wire bonds are plastically deformed such that they extend less than 50 microns above the active surface of the die. Preferably, the wire bond is pushed by engagement with a blade having a filleted edge region for contacting the wire bond. Preferably, the method further comprises the steps of: -9-200915522 applying an encapsulating bead onto the wire bond; and moving a profiled work surface over the active surface for the package The beads of the sealant are flattened. Preferably, the beads of the encapsulant have a profiled surface which is flat, parallel to the active surface and less than 100 microns apart. Preferably, the beads of the encapsulant have a flat, profiled surface that is inclined relative to the active surface. Preferably, the encapsulant is an epoxy material having a viscosity greater than 7 〇 〇 C P when uncured. In a preferred embodiment, the encapsulant is an epoxy material that is thixotropic when uncured. Preferably, the method further comprises the steps of: placing the profiled work surface adjacent to and spaced apart from the active surface to define a gap; and applying a bead of the encapsulant to the The contact pad is placed such that one side of the bead contacts the profiled working surface and a portion of the bead extends into the gap and reaches the active surface. Preferably, the active surface has a functional element 'which is less than 260 microns from the contact pads on the crystal. In a particularly preferred form, the die is an ink jet print head IC and the functional elements are nozzles' ink is ejected through the nozzles. In some embodiments, the printhead IC is mounted in a printer such that the nozzle is less than 100 microns from the paper path during use. -10-200915522 Preferably the 'support structure' has a wafer mounting area and a conductor mounting area, the die is supported on the wafer mounting area, and a plurality of electrical conductors are at least partially supported on the conductor mounting On the area, wherein the wafer mounting area is raised relative to the conductor mounting area. Preferably, the wafer mounting area is raised by more than 100 microns relative to the conductor mounting area. Preferably, the support structure has a first order between the wafer mounting area and the conductor mounting area. In some embodiments, the plurality of conductors are punctured into the flexible printed circuit board (flexible pc B ) by a row of bond pads proximate the edge of the die, the bond pads being separated The contact pads on the die are over 2 mm. Preferably, the support structure is a liquid crystal polymer (LCP) molding. According to a third aspect, the present invention provides a bead of an encapsulant extending along an edge of a die mounted on a support structure. A method of droplet profile operation, the method comprising the steps of: depositing beads of an encapsulant along an edge of the die on a wire bond; placing a profiled work surface on the die from the die At a predetermined spacing, the profiled working surface is moved across the bead prior to curing of the bead of the encapsulant to reshape the bead of the bead; and the bead of the encapsulant is cured. The present inventors have discovered that the encapsulant can be effectively formed by a profiled work surface without stripping the encapsulant from the wire bond. The normal convex upper surface of the encapsulant bead can be pushed toward the side by the profiled work surface. -11 - 200915522 By means of this low encapsulant bead, the active surface can be brought closer to the other surface without contact. For example, the array of nozzles on a column of print head ICs can be from 300 microns to 400 microns from the paper path. The nozzle array on the print head 1C can be less than 1 μm from the paper path by collapsing or flattening the wire bond arc prior to applying an encapsulant and contouring it. Preferably, the wire bonds extend into an arc from respective contact pads of the die to corresponding conductors on the support structure and the method includes the steps of: pushing the wire bond to bond the wire Plastically deforming; and releasing the wire bond such that the plastic deformation maintains the wire bond in a relatively flat cross-sectional shape. Preferably, the die has a functional surface having a functional element, the contact pad being formed on an edge of the active surface, the wire bond having a diameter of less than 40 microns and the arc extending Above the active surface of the die is greater than 100 microns. Preferably, the wire bonds are plastically deformed such that they extend less than 50 microns above the active surface of the die. Preferably, the wire bond is pushed by engagement with a blade having a filleted edge region for contacting the wire bond. Preferably, the bead of the encapsulant has a profiled surface which is flat, parallel to the active surface and less than 1 〇〇 micrometer apart. Preferably, the encapsulant beads The droplet has a flat, profiled surface that is inclined relative to the surface used for -12-200915522. Preferably, the encapsulant is an epoxy material that does not have a viscosity greater than 700 cp. Preferably, the encapsulant is an epoxy resin material '## not thixotropic (t h i X 〇 t r 〇 p i c ). Preferably, the method further comprises the steps of: placing the profiled work surface spaced apart from the existing @@^® to define a gap; and applying the bead of the encapsulant to The 'insults' on one of the contact pads contact the profiled work surface and a $#M# gap of the bead and reach the active surface. Preferably, the active surface has a functional element 1 {both'. The contact pads on the particles are less than 260 microns apart. In a preferred form, the die is an ink jet print head 1C and the functional elements are ejected through the nozzles. In some embodiments, the printhead IC is within a printer such that the nozzle is less than meters from the paper path during use. Preferably, the support structure has a wafer mounting area and a mounting area, the die is supported on the wafer mounting area and a plurality of portions are at least partially supported on the conductor mounting area, wherein the wafer is opposite to the semiconductor mounting area The conductor mounting area is raised. Preferably, the wafer mounting area is over 1 〇〇 micron relative to the conductor mounting area. In a particularly preferred embodiment, the support structure is between the wafer mounting area and the conductor mounting area. When curing, the adjacent beads drop to the middle and the crystal, the 'ink is mounted 100 micro-conductor electrical conductor mounting area is raised by a level of -13 - 200915522. Preferably, the plurality of conductors are The pads are interposed into a flexible printed circuit board (flexible pc B ) along the bond pads closest to the edges of the die. The bond pads are more than 2 mm from the contact pads on the die. Preferably, the support structure is a liquid crystal polymer (LCP) molding. According to a fourth aspect, the present invention provides a method for applying an encapsulant to a die mounted on a support substrate. The method includes the steps of providing a die mounted on a support substrate having a back surface in contact with the support structure and an active surface opposite the back surface, the active surface having electricity a contact pad; a barrier disposed adjacent the electrically conductive contact pad and spaced apart from the active surface to define a gap; and depositing a bead of encapsulant on the electrical contact pad such that One side of the bead drops contacts the barrier and a portion of the bead extends into the gap and onto the active surface. Placing a barrier on the active surface such that it defines a narrow spacing such that the shape of the front end of the encapsulant (the line of contact between the encapsulant and the active surface) can be further Closely controlled. Any change in flow rate from the encapsulant of the needle can cause ridges or depressions in the height of the PCB side of the bead and/or bead. The fluid resistance created by the gap between the barrier and the active surface means that the encapsulation dose flowing into the gap and onto the active surface is nearly fixed. The reduced flow change causes the front end of the encapsulant to closely correspond to the shape of the barrier. Further -14 - 200915522 The large encapsulant front end control allows the functional elements on the active surface of the die to be closer to the contact pads. Preferably, the barrier is a profiled work surface and the method further comprises the step of: moving the profiled work surface over the active surface to planarize the beads of the encapsulant. Preferably, the method further comprises the steps of: electrically bonding the contact pads on the die to respective conductors on the support substrate by wire bonding prior to depositing the beads of the encapsulant, the wires Each of the joints extends an arc from the contact pad to the conductor; pushing the wire bond to collapse the arc and plastically deform the wire bond; and releasing the wire bond such that the plastic deformation joins the wire Maintain a flat cross-sectional shape. In a more preferred form, the active surface has a functional element, the contact pad being formed on an edge of the active surface, the wire bond having a diameter of less than 40 microns and the arc extending Above the active surface of the die is greater than 100 microns. Preferably, the wire bonds are plastically deformed such that they extend less than 50 microns above the active surface of the grain. In another preferred form, the wire bond is pushed by engagement with a blade having a filleted edge region for contacting the wire bond. Preferably, the bead of the encapsulant has a profiled surface which is flat, parallel to the active surface and spaced less than 1 〇〇 micro -15 - 200915522 m. Preferably, the beads of the encapsulant have a flat, profiled surface that is inclined relative to the active surface. Preferably, the encapsulant is an epoxy material having a viscosity greater than 7 〇〇 cp when uncured. Preferably, the encapsulant is an epoxy material which is thixotropic when uncured. Preferably, the active surface has functional elements that are in contact with the die. The pads are less than 260 microns apart. In a particularly preferred form, the die is an ink jet print head 1C and the functional elements are nozzles through which ink is ejected. Preferably, the print head 1C is mounted in a printer such that the nozzles are less than 1 〇 microns from the paper path during use. Preferably, the support structure has a wafer mounting region and a conductor mounting region, the die is supported on the wafer mounting region, and a plurality of electrical conductors are at least partially supported on the conductor mounting region. The mounting area is raised relative to the conductor mounting area. In a particularly preferred form, the wafer mounting area is raised by more than 100 microns relative to the conductor mounting area. In a preferred embodiment, the support structure has a first order between the wafer mounting area and the conductor mounting area. In a particularly preferred embodiment, the plurality of conductors are drawn into a flexible printed circuit board (flexible PCB B) by a row of bond pads closest to the edge of the die. The pad is spaced apart from the die by more than 2 mm. Preferably, the support structure is a liquid crystal polymer (LCP) molding material-16-200915522. According to a fifth aspect, the present invention provides a conductor for applying an encapsulant to a die and a support substrate. a method of wire bonding, the method comprising the steps of: forming a bead of the encapsulant on a profiled work surface; placing the profiled work surface such that the bead contacts the die; and The die moves the profiled work surface for covering the wire bond with the encapsulant. Sweeping the encapsulant through the wire bond with a profiled work surface provides control of the front end of the encapsulant and control of the height of the encapsulant relative to the die. The movement of the profiled work surface relative to the die can be tightly controlled to shape the encapsulant into the desired shape. Using an example of a row of die grains, the encapsulant can be shaped to present an inclined surface that raises a high point above the wire bond from the nozzle surface. This can be utilized by the print head maintenance to maintain a constant contact pressure on the sweeping mechanism. This is further explained below by reference to the drawings. However, it will be appreciated that the encapsulant can be shaped to have ridges, sipe, grooves, etc. by using a profiled work surface of a particular shape and detailed movement of the die. Preferably, the method further comprises the step of: immersing the profiled work surface in a container of the encapsulant material to form an encapsulant of beads onto the profiled work surface. Selecting the upper surface 'the profiled work surface is a blade having a straight edge and the method further comprises the step of orienting the blade such that the straight edge is the lowest edge of -17-200915522 and The straight edge is immersed in the encapsulant material to form beads of the encapsulant along the straight edge. Preferably, the die has a functional surface with a functional component and a plurality of contact pads formed along an edge for engaging the wire such that the wire bond extends into a The contact pads each reach an arc of each conductor having a diameter of less than 40 microns and the arc extending above 100 microns above the surface of the die. Preferably, the method further comprises the steps of: urging the wire bond to collapse the arc and plastically deforming the wire bond prior to encapsulation; and releasing the wire bond such that the plastic deformation joins the wire Maintain a flat cross-sectional shape. Preferably, the wire bonds are plastically deformed such that they extend less than 50 microns above the active surface of the die. Preferably, the wire bond is pushed by engagement with a blade having a filleted edge region for contacting the wire bond. Preferably, the encapsulant covering the wire bonds has a profiled surface which is flat, parallel to the active surface and spaced less than 100 microns apart. Preferably, the beads of the encapsulant have a flat, profiled surface that is inclined relative to the active surface. Preferably, the encapsulant is an epoxy material having a viscosity greater than 700 cp when uncured. Preferably, the encapsulant is an epoxy material which is thixotropic when uncured -18-200915522. Preferably, the functional elements are less than 260 microns from the contact pads on the die. In a more preferred form, the die is an ink jet print head 1C and the functional elements are nozzles through which ink is ejected. Preferably, the print head IC is mounted in a printer such that the nozzle is less than 1 micron from the paper path during use. Preferably, the support structure has a wafer mounting area and a conductor mounting area. A die is supported on the wafer mounting region and a plurality of electrical conductors are at least partially supported on the conductor mounting region, wherein the wafer mounting region is raised relative to the conductor mounting region. In a particularly preferred form, the wafer mounting area is raised by more than 100 microns relative to the conductor mounting area. In another preferred form, the support structure has a first order between the wafer mounting area and the conductor mounting area. In a preferred embodiment, the plurality of conductors are punctured into a flexible printed circuit board (flexible PCB) by a row of bond pads closest to the edge of the die. The pad is spaced apart from the die by more than 2 mm. Preferably, the support structure is a liquid crystal polymer (LCP) molded article. [Embodiment] Figure 1 shows a general technique for applying an encapsulant bead to a wire bond. A die 4 is mounted to a support structure 6 adjacent the edge of a flexible PCB 8 (flexible printed circuit board). The die 4 has a row of contact pads 10 along one edge and the flexible PCB 8 has a corresponding bond pad 112. Wire bond 16 extends from contact pad 10 to bond pad 112. Power -19- 200915522 and data are transmitted to the die 4 via conductive traces 14 within the flexible PCB 8. This is a simplified representation of the die mounted in many electronic packages. Mounted on an LCP (Liquid Crystal Polymer) molding for receiving from a neighboring flexible PCB, as described in U.S. Patent Application Serial No. RRC001US, which is hereby incorporated by reference. The print head 1C die, which is incorporated herein, is an example of such a die mounted construction. As will be appreciated by a general practitioner, the die can be mounted directly onto a rigid PCB on which the wires are formed. Wire bonds 16 are covered in the beads of an encapsulant 2 to protect and reinforce the wire bonds. The encapsulant 2 is applied directly from a discharge needle 18 to the wire bond 16. Typically the encapsulant bead 2 is three separate beads, one or two encapsulants 20 referred to as 'dams', and an encapsulant known as 'fill' twenty two. The dam encapsulant 20 has a higher viscosity than the encapsulant 22 and the dam encapsulant 20 is used to form a channel for containing the encapsulant beads. The height Η of the bead 2 above the die 4 is typically about 500-600 microns. This does not cause problems in most electronic devices. However, if the die has a working surface that must work in close proximity to the other surface, the bead will be an obstacle. The die is raised relative to the flexible PCB. Figure 2 shows a first step support structure 6 which raises the wafer mounting area 26 relative to the PCB mounting area 24 (or at least the area in which the PCB bond pads 12 are mounted). By the die 4 on the elevated wafer mounting area 26, the arc of the -20-200915522 wire bond 16 is lower relative to the active surface 28 of the die 4. In fact, the end of the wire bond 16 attached to the contact pad 10 can be the apex of the arc (it should be remembered that the wire bond arc is used to accommodate some relative motion of the die and the PCB). When the wire bond 16 is covered by the encapsulant 2, the bead has a reduced height H above the active surface 28 of the die 4. If the encapsulant bead 2 uses two dam encapsulants 20 and one enamel encapsulant 22, the position, volume and viscosity of the beads must take this order into account. Droplet heights of less than 1 μm are easily achieved, and by additional means such as line arc collapse and bead profile work (discussed below), bead drops of less than 50 microns can be achieved height. By the die 4 being raised to 410 μm above the flexible PCB 8, the height of the wire bond 16 is about 34 microns above the die. By the die being raised to 610 microns above the flexible PC B 8, the wire bond is about 20 microns. Further raising the grain again has little or no further reduction in the wire bond height (about 20 microns) of the order of 7 10 microns. The encapsulant bead is shaped by a cross-sectional working blade. Figures 3A through 3C show that the encapsulant 2 is profiled with a cross-sectional working blade 30. The support structure 6 is again graded to reduce the height of the wire bond 16 above the die 4. Prior to curing of the epoxy encapsulant 2, the cross-sectional working blade 30 is moved over a predetermined path across the die 4 to engage the wire. As shown in Figure 3B, the blade 30 moves the top of the bead to its flex PCB side to form a flat top surface 32-21-200915522, which is significantly reduced above the die 4. The height of the place. The encapsulant bead 2 can have a plurality of separate beads as shown in Figures 1 and 2, or can be a single drop of a substance. However, in order to achieve tighter dimensional control of the profiled encapsulant, the encapsulant used should be thixotropic, after being deposited from the discharge needle, or by the blade 3 After profile 0, the material should not flow due to its own weight, but should maintain its shape until it solidifies. This requires the epoxy to have an uncured viscosity of greater than about 7 〇〇 cp. A suitable encapsulant is the DYMAX 900 1 -E-v 3.1 wafer encapsulant manufactured by Dymax Corporation, which has a viscosity of about 800 cp when uncured. The blade 30 can be ceramic (glass) or metal and is preferably about 200 microns thick. It will be appreciated that the relative motion of the blade with the die 10 and the die 4 can be precisely controlled. This allows the height to be determined by the tolerance of the wire bonding process. As long as the enthalpy is greater than the nominal height of the wire bond arc above the die plus the maximum tolerance, the encapsulant 2 will cover and protect the wire bond 16 . With this technique, the height Η can be easily reduced from 500-600 microns to less than 3 microns. If the height of the wire bond arc is also reduced, the height of the encapsulant bead can be less than 1 〇〇 micron. Applicants have used this technique to profile the encapsulant on the printhead die to a height as low as 50 microns at the low point. As shown in Fig. 3C, the lowest point is at the front end of the encapsulant and the blade 30 forms an inclined surface 3 2 at the top of the bead 2 . The inclined surface can be utilized by the printhead maintenance system when the paper ash and the dried ink are removed from the nozzle face. This demonstrates that the ability of this technique not only reduces the height of the -22-200915522 encapsulant bead drop' can also form a surface that performs other functions than the encapsulation wire bond. The edge profile of the blade and the path of the blade relative to the die can be constructed to form a surface having various shapes for various purposes. Plastic Deformation of Wire Bonding Arcs Figures 4A through 4C show another technique for reducing the profile of wire bonding. Figure 4A shows the die 4 connected to the flexible PCB 8 via wire bonds 16. Although the stepped support structure 6 has reduced the height of the wire engaging arc compared to the flat support structure, the wire bond still has a natural tendency to bend upward rather than downward toward the corners of the step. The wire bond 16 has a diameter of typically about 32 microns and has a tensile force of about 3 to 5 grams force. This pulling force is the tensile load required to break the connection with the contact pad 10 or the bonding pad 12. Due to the fragility of these structures (one of which is the application of encapsulants), the traditional wisdom is to avoid the wire bond arcs from contacting other solid surfaces. As shown in Fig. 4B, the arc of the wire joint 16 can be collapsed by the wire pusher 34. The wire pusher 34 pushes the wire 16 to make it elastically and plastically deformable. The applicant of the present application has shown that contact with the wire pushing member 34 causes work hardening on the wire, but as long as the force is not excessive, it does not break. The end of the wire pushing member 34 is rounded to avoid stress concentration points. The wire pusher 34 can be a stylus for contacting a single wire bond or a blade for simultaneously pushing a plurality of wire bonds. Referring now to Figure 4C, the wire pusher 34 is retracted and the wire springs back toward its original shape of -23-200915522 to relieve the elastic deformation. However, the plastic deformation continues to exist and the wire bonding height above the die 4 is greatly reduced. Tests have shown that using this technique allows a wire bond loop height of initially 200 microns to be reduced to about 45 microns. Tests have also shown that the tensile strength of the plastically deformed wire remains at about 3 to 5 grams of force. The collapse of the wire bond is uncontrolled and the wire bond is somewhat randomly deformed. However, bringing the wire bond closer to the die provides wire bonding that is more consistently shaped. The study by the applicant of the present application showed that contacting the 200 to 300 micron wire for the crystal grain provided the best results. The die 4 and the flexible P C B 8 are mounted on a flat support structure 6 as shown in Fig. 4D. As discussed above, this means that the initial loop height of the wire bond arc is much higher than about 400 microns above the die 4. Therefore, the wire has more plastic deformation when the ring is pushed by the wire pressing member. Even so, the applicant's results show that the remaining loop height after pushing is about 20-50 microns. Figures 5A and 5B show the wire bonds 16 of a couch covered by an encapsulant bead 2. Even if there is no bead profile profiling prior to curing, the bead height above the die is still much less than the height required for the bead to encapsulate the original undeformed wire loop. Applying Encapsulant with Profiled Work Blades Figures 6A, 6A and 6C show the use of the profiled work blade 30 instead of a discharge needle (see Figures 1 and 2) to apply the encapsulant beads. As previously discussed, the flow rate of the encapsulant from the discharge needle will vary and this -24-200915522 will have a large change in the position of the front end of the encapsulant on the active surface of the die 4. Therefore, any functional component on the active surface of the die 4 must be sufficiently spaced apart from the contact pad 10 to allow for a gentle front end of the encapsulant. Application of the encapsulant with the profiled working blade avoids the problems caused by fluctuations in the flow rate from the discharge needle. As shown in FIG. 6A, the encapsulant bead 40 can be formed in the cross section simply by dipping the profiled working blade 30 into a container of an uncured encapsulant epoxy. The work blade 30 is turned on. Of course, the bead 40 can also be formed by other conventional means, such as moving the discharge needle along one end of the blade 3 . Figure 6B shows that the blade 30 has been lowered to contact the bead 40 onto the die 4. As the encapsulant material contacts the surface of the die, it wets along the surface while remaining pressed by the edge of the blade. The blade 30 is held a predetermined height above the die 4 and is moved across the bead 2 to planarize the bead and reduce its profile. An encapsulant displaced by the blade 30 from the tip end of the bead is spread on the PCB side of the bead 2. Whether or not the encapsulant is more dispersed on the PCB than necessary is irrelevant. As long as the wire bonds 16 and the bond pads 12 are covered and available, any additional encapsulant will not be detrimental on the surface of the PCB 8. In Figure 6C, the wire bond 16 height has been reduced by collapsing the wire arc in accordance with the techniques described above. As previously discussed, the bead 2 placed by the discharge needle need not be large enough to cover the size of the wire joint 1 6 坍 -25- 200915522. Furthermore, when the encapsulant 2 is profiled, the blade 30 can be closer to the die 4 without being bonded to the wire. Thus, the bead profile in FIG. 6C is greater than that in FIG. 6B. The bead drop profile is low. Encapsulant front end control When the encapsulant material is applied from the discharge needle, a small change in flow rate causes the beads to ridge at a point where the flow rate is large. The side of the bead that is in contact with the active surface of the die is not a pen, but rather a significant perturbation. These disturbances must accommodate any functional elements on the contact pads and the active surface. The spacing between the contact pads and the functional components will use the valuable 'chip real estate'. In this case, the head dies of 260 micrometers between the contact pad and the first row of nozzles are issued. Better encapsulant front end control reduces the spacing between the contacts and the work elements, as well as the overall size of the die. Therefore, this design makes it possible to make more wafers from the original wafer. As shown in Figures 7A and 7B, the profiled working blade 30 controls the leading end 36 of the encapsulant bead 2. The blade 30 is placed over the die 4 for a gap 42 between the lower edge and the active surface 28. When the discharge needle 18 discharges the encapsulant material, it flows on the active surface, and one side of the blade and a material fillet extend through the gap 42. Due to the relationship of the flow resistance generated, the flow rate fluctuation is caused by the flow rate. This is the result of the addition of the printed seal between the 値 and the 値 被 被 44 44 44 44 44 -26 -26 -26 -26 Thus the front end of the encapsulant 3 6 closely conforms to the line of the lower edge of the blade 3 . As shown in Fig. 7B, the profiled working blade 30 has been subjected to profile work for positioning the bead of the encapsulant when the encapsulant bead 2 is discharged from the discharge needle. The blade 30 simply moves over the die 4 in a direction away from the nozzle 38. This maintains the front end 36 of the encapsulant in position and flattens the cross-section of the encapsulant bead 2 placed on the wire bond 16. The invention has been described herein by way of example. A person skilled in the art will readily recognize many variations and modifications of the spirit and scope of the invention without departing from the invention. BRIEF DESCRIPTION OF THE DRAWINGS [0007] Embodiments of the invention will now be described by way of example with reference to the accompanying drawings, in which: FIG. 1 is a schematic representation of a general prior art technique for applying a bead drop of an encapsulant to a wire bond. Figure 2 is a schematic representation of a die mounted on a support structure having a wafer mounted elevated relative to the flexible PCB mounting region, Figures 3A, 3B and 3C being the envelope The droplets are profiled into a schematic representation of a desired shape by using a movable blade; Figures 4A through 4D are schematic representations of the wire bonds profiled by the plastic profile; 27- 200915522 Figures 5A and 5B show the reduction in the height of the encapsulant bead bonded by the plastically deformed wire; Figures 6A to 6C show the encapsulant bead by using the blade of the profiled operation Applied to the wire bond; and Figures 7A and 7B show a profiled work blade that is used to control the encapsulant beads on the surface of the die. [Main component symbol description] 4: Die 6: Support structure 8: Flexible PCB 10: Contact pad 12: Bonding pad 1 4: Conductive trace 1 6: Wire bonding 1 8: Discharge needle 2: Encapsulant, bead Drop 2 0 : Dam encapsulant 22 : Mounting encapsulant 24 : PCB mounting area 2 ό · Wafer mounting area 28 : Active surface 3 〇: Profiled working blade 3 2 : Flat top surface, inclined Face -28- 200915522 34: Line 40: Pack 36: Pack 42: Room 44: Pack 38: Spray pusher sealant Bead sealant Front-end gap sealant substance mouth -29