200848271 九、發明說明 【發明所屬之技術領域】 本發明係有關於噴墨噴嘴組件及製造噴墨噴嘴組件的 方法。本發明主要是爲了降低在供電給噴墨致動器時的電 的損失而被硏發的。 【先前技術】 本申請案先前已描述許多使用熱彎曲致動的MEMS 噴墨噴嘴。熱彎曲致動大體上係指由一種有電流通過之材 質的熱膨脹所產生之相關於另一材質的彎曲運動。非必要 地，透過一槳片或槳葉的運動，該所產生的彎曲運動可被 用來將墨水從一噴嘴開口噴出，該運動可在該一噴嘴室內 產生一壓力波。 熱彎曲噴墨噴嘴的一些代表性種類在列於參考資料欄 中的專利與專利申請案中被例示出來，這些參考資料的內 容藉由此參照而被倂於本文中。 本案申請人的美國專利第6,416,167號中揭露了一種 噴墨噴嘴其具有一設置在一噴嘴室內的槳葉及一設置在該 噴嘴室外面的熱彎曲式致動器。該致動器的形式爲熔接至 一非導電材質（如，二氧化矽）的上被動樑上之導電材質 (如，氮化鈦）的下主動樑。該致動器透過一穿過該噴嘴 室的壁上的槽的臂連接至該槳葉。在將一電流通過該下主 動樑時，該致動器會向上彎曲，該槳葉因而朝向一設在該 噴嘴室的室頂上的噴嘴開口移動，藉以將一墨水滴噴出。 -4- 200848271 此設計的一項好處爲它的結構簡單。此設計的缺點爲該槳 葉的兩面對著該噴嘴室內之相當黏稠的墨水工作。 本案申請人的美國專利第6,260,953號中揭露了一種 噴墨噴嘴，在此噴墨噴嘴中該致動器形成該噴嘴室的一活 動的室頂部分。該致動器的形式爲一被一聚合體物質圍繞 之導電物質的蜿蜒的芯材。在致動時，該致動器朝向該噴 嘴室的室底板彎曲，升高在該室內的壓力並迫使一墨水液 滴從設在該室的室頂上的噴嘴開口射出。該噴嘴開口是被 設置在該室頂之不動的部分上。此設計的一項好處是該活 動的室頂部分的一個面需要對著該噴嘴室內之相當黏稠的 墨水工作。此設計的缺點爲該被一聚合體物質圍繞之蜿蜒 的導電元件很難用MEMS製程來製造。 本案申請人的美國專利第6,623，101號中揭露了一種 噴墨噴嘴其包含一具有一可活動的室頂部分的噴嘴室，該 室頂上設有一噴嘴開口。該可活動的室頂部分透過一臂連 接至一設在該噴嘴室外面的熱彎曲式致動器。該致動器的 形式爲一上主動樑其與一下被動樑間隔開。藉由將該主動 樑與該被動樑間隔開來，該熱彎曲效率被最大化，因爲該 被動樑不會如該主動樑的散熱器般地作用。在將電流通過 該上主動樑時，其上開設有噴嘴開口之可活動的室頂部分 被促使朝向該噴嘴室轉動藉以將墨水從噴嘴開口射出。因 爲該噴嘴開口與室頂部分一起移動，所以液滴飛行方向可 藉由適當地改變該噴嘴邊緣的形狀來控制。此設計的一項 好處爲只有該活動的室頂部分的一個面必需要對著該噴嘴 -5- 200848271 室內的之相當黏稠的墨水工作。另一個好處爲將該 被動樑件分隔開來可讓熱損失減至最小。此設計的 該將該主動與被動樑件分隔開來會讓結構堅固性鬆 在所有的MEMS噴墨噴嘴設計中，存在著將 最小化的需求。在噴嘴設計是造成電的損失的主要 構所在的例子中，將電的損失最小化是特別重要的 ，介於一致動器與一供應電流至該致動器的CMOS 間的一相對長的距離會讓電的損失更加嚴重。再者 或扭曲電流路徑亦會讓電的損失更嚴重。 通常，在噴墨噴嘴中的致動器材質係選自於一 滿足數項要件的物質。在機械式熱彎曲致動的噴嘴 中，這些要件包括導電性，熱膨脹係數’楊式模數 在熱汽泡形成式噴墨噴嘴的例子中’這些要件包括 ，抗氧化性，抗爆裂性等等。因此’將可被瞭解的 動器材質的選擇通常是多種特性的折衷，且該致動 不一定具有最佳的導電性。在致動器材質本身具有 導電性的例子中，將噴嘴組件中的電的損失減至最 別重要。 最後，在噴嘴設計上的任何改進都應與標準的 製程相容。例如，某些材質與MEMS製程是不相 因爲它們會導致晶圓廠的污染。 由以上所述，將可被瞭解的是’對於噴墨噴嘴 與製造上的改進存在著需求’用以將電的損失減至 提供更有效率之列印頭的液滴噴射。對於電的損失 主動與 缺點爲 動。 電損失 不利結 。例如 電極之 ，彎折 種能夠 的例子 等等。 導電性 是，致 器材質 次佳的 小是特 MEMS 容的， 的設計 最小並 會因爲 -6 - 200848271 噴嘴設計之固有的外觀而被惡化之機械式熱彎曲致動的噴 墨噴嘴的設計與製造的改良存在著特殊的需求。 【發明內容】 在本發明的第一態樣中，本發明提供一種形成一介於 一噴墨噴嘴組件內的一電極與一致動器之間的電氣連接的 方法，該方法包含的步驟爲： (a )提供一具有一驅動電路層的基材，該驅動電路 包括該電極用以連接至該致動器； (b )形成一絕緣物質壁於該電極上； (c )在至少該壁上形成一通孔（via )，該通孔露出 該電極； (d)使用無電電鍍將導電物質塡入該通孔中用以提 供一連接器柱；及 (e )形成至少部分的該致動器於該連接器柱上，藉 以提供電氣連接於該致動器與該電極之間。 選擇上地，介於該致動器與該電極之間的距離至少5 微米。 選擇上地，該驅動電路層爲一矽基材的CMOS層。 選擇上地，該驅動電路包括一對用於每一噴墨噴嘴組 件的電極，每一電極都用各自的連接器柱連接至該致動器 〇 選擇上地，該絕緣物質壁係由二氧化矽構成。 選擇上地，該通孔具有垂直於該基材的一面的側壁。 -7- 200848271 選擇上地，該通孔具有1微米或更大之最小截面直徑 〇 選擇上地，該導電物質爲金屬。 選擇上地，該導電物質爲銅。 在另一態樣中，一種方法被提供，其進一步包含的步 驟爲： 在該無電電鍍之前，沉積一催化劑層於該通孔的基部 上。 選擇上地，該催化劑爲鈀。 選擇上地，該導電物質在形成該致動器之前用化學機 械平坦化處理加以平坦化。 選擇上地，該致動器爲一熱彎曲式致動器，其包含一 平面的主動樑件其機械式地與一平面的被動樑件協作。 選擇上地，該熱彎曲式致動器至少部分地界定一用於 該噴墨噴嘴組件的噴嘴室的室頂。 選擇上地，該絕緣物質壁界定該噴嘴室的一側壁。 選擇上地，步驟（e )包含沉積一主動樑物質於一被 動樑物質上。 選擇上地，由該主動樑物質所構成的該主動樑件從該 連接器柱的頂部延伸於一垂直於該柱的平面上。 在另一態樣中，本發明提供一種方法其進一步包含的 步驟爲： 在該主動樑物質的沉積之前，沉積一第一金屬墊於該 連接器柱的頂部，該第一金屬墊被建構來促進電流從該連 -8 - 200848271 接器柱流至該主動樑件。 選擇上地，該平面的主動樑件包含一彎曲的或蜿蜒的 樑元件，該樑元件具有一第一端其被放置在一第一連接器 柱上面及一第二端其被放置在一第二連接器柱上面，該第 一及第二連接器柱彼此相鄰。 在另一態樣中，本發明提供一種方法其進一步包含的 步驟爲： 在該主動樑物質的沉積之前，沉積一或多個第二金屬 墊於該被動樑物質上，該第二金屬墊被放置來促進電流流 入該樑元件的彎曲區域中。 在第二態樣中，本發明提供一種列印頭積體電路其包 含一基材，其具有複數個噴墨噴嘴組件形成在該基材的表 面上，該基材具有驅動電路用來供應電力至該等噴嘴組件 ，每一噴嘴組件都包含： 一噴嘴室用來容納墨水，該噴嘴室具有一界定於其內 的噴嘴開口； 一致動器用來經由該噴嘴開口噴出墨水； 一對設置在該基材的該表面上之電極，該等電極被電 氣地連接至該驅動電路；及 一對連接器柱，每一連接器柱都將一個別的電極電氣 地連接至該致動器， 其中每一連接器柱都從個別的電極直線地延伸至該致 動器。 選擇上地’每一連接器柱相對該基材的該表面是垂直 -9- 200848271 的。 選擇上地’介於該致動器與該等電極之間的最短距離 爲至少5微米。 選擇上地’該等連接器柱的最小截面直徑爲2微米或 更大。 選擇上地，該等噴嘴組件被安排成複數個噴嘴列，該 等噴嘴列沿著該基材縱長向地延伸。 選擇上地，介於一噴嘴列內的相鄰噴嘴開口之間的距 離係小於5 0微米。 選擇上地，該致動器爲一熱彎曲式致動器，其包含一 平面的主動樑件其機械式地與一平面的被動樑件協作。 選擇上地，該熱彎曲式致動器至少部分地界定一用於 該噴墨噴嘴組件的噴嘴室的室頂，該噴嘴開口被界定在該 室頂上。 選擇上地，一絕緣物質壁界定該噴嘴室的側壁。 選擇上地，該主動樑件被電氣地連接至該等連接器柱 的頂部。 選擇上地，該主動樑件的一部分被放置在該該等連接 器柱的頂部上面。 在另一態樣中，本發明提供一列印頭積體電路其更包 含一第一金屬墊其放置在每一連接器柱的頂部與該主動樑 件之間，每一第一有間隙的金屬墊都被建構來促進電流從 一'個別的連接器柱流至該主動棟件。 選擇上地，該主動樑件是由選自於包含：鋁合金；氮 -10- 200848271 化鈦與氮化鈦鋁的組群中之主動樑物質所構成的。 選擇上地，該主動樑件是由釩鋁合金所構成的。 選擇上地，該平面的主動樑件包含一包含一彎曲的或 蜿蜒的樑元件，該樑元件具有一第一端其被放置在一第一 連接器柱上面及一第二端其被放置在一第二連接器柱上面 ，該第一及第二連接器柱彼此相鄰。 在另一態樣中，本發明提供一種列印頭積體電路其更 包含至少一第二金屬墊，該第二金屬墊被放置來促進電流 流入該樑元件的彎曲區域內。 在另一態樣中，本發明提供一種列印頭積體電路其更 包含在該室頂上之疏水性聚合物的外表面層。 選擇上地，該外表面層界定該列印頭積體電路的一平 面的噴墨面，該平面的噴墨面除了該等噴嘴開口之外沒有 實質上的外形結構。 選擇上地，該疏水性聚合物機械性地密封一介於該熱 彎曲式致動器與該噴嘴室之間的間隙。 在另一態樣中，本發明提供一種包含複數個噴墨頭積 體電路的頁寬噴墨列印頭，該噴墨頭積體電路包含一基材 ，其具有複數個噴墨噴嘴組件形成在該基材的表面上’該 基材具有驅動電路用來供應電力至該等噴嘴組件，每一噴 嘴組件都包含： 一噴嘴室用來容納墨水，該噴嘴室具有一界定於其內 的噴嘴開口； 一致動器用來經由該噴嘴開口噴出墨水； -11 . 200848271 一對設置在該基材的該表面上之電極，該等電極被電 氣地連接至該驅動電路；及 一對連接器柱，每一連接器柱都將一個別的電極電氣 地連接至該致動器， 其中每一連接器柱都從個別的電極直線地延伸至該致 動器。 【實施方式】 圖1及2顯示如本案申請人稍早於2002年12月4日 提申之美國專利申請案第11/607,976號中描述的一噴嘴 組件，該申請案的內容藉由此參照被倂於本文中。該噴嘴 組件400包含一噴嘴室401其形成在一矽基材4〇3的一鈍 態化的CMOS層402上。該噴嘴室是由一室頂404及從該 室頂延伸至該鈍態化的C Ο M S層4 0 2的側壁4 0 5所界定出 來的。墨水藉由一與供墨渠道407流體連通的墨水入口 406而被供應至該噴嘴室401，該供墨渠道接受來自該矽 基材4 0 3被測的墨水。墨水藉由界定在該室頂4 〇 4上的噴 嘴開口 408從該噴嘴室401中被噴出。該噴嘴開口 408與 該墨水入口 4 0 6錯開來。 如圖2中清楚看到的，室頂4 〇 4具有一活動部分4 0 9 其界定該室頂的總面積的絕大部分。該噴嘴開口 4 0 8與噴 嘴邊緣4 1 5被界定在該活動部分4 0 9上，使得該噴嘴開口 與該噴嘴邊緣與該活動部分一起運動。 該活動部分409是由一具有一平面的上主動樑411與 -12- 200848271 一平面的下被動樑4 1 2的熱彎曲式致動器4 1 0所界定。該 主動樑4 1 1被連接至一對電極接點（正極與地極）。電極 416與COMS層中的驅動電路連接。 當需要從該噴嘴室4 0 1噴出一墨水液滴時，一電流流 經介於兩個接點4 1 6之間的主動樑4 1 1。該主動樑4 1 1被 該電流迅速地加熱並相對於該被動樑4 1 2膨脹，藉以造成 該致動器410 (其界定室頂404的該活動部分409)向下 朝向該基材403彎曲。致動器410的此一運動造成墨水被 該噴嘴室40 1內快速增加的壓力從該噴嘴開口噴出。當電 流停止時，該室頂404的活動部分409就能回復到它靜止 的位置，這可將墨水從該入口 406吸入到噴嘴室401內， 以供下次噴墨之用。 在圖1及2所示的噴嘴設計中，界定至少一部分的噴 嘴疏401的室頂404對於致動器410而言是有利的。這不 只簡化了噴嘴組件400的整體設計與製造，更提供一更高 的噴墨效率，因爲只有該致動器4 1 0的一個面必需要對著 該噴嘴室內的之相當黏稠的墨水工作。相較而言，具有一 設置在噴嘴室內部的致動器槳葉的噴嘴組件效率較差，因 爲該致動器的兩面必需要對該室內的墨水工作。 然而，在該致動器410至少部分地界定該室401的室 頂4 04的結構中，無可避免地在該主動樑41 1與該等和主 動電極4 1 1相連接的電極4 1 1之間有一相對長的距離。電 極4 1 6與致動器4 1 0之間之相對長的距離，迂迴曲折的電 流路徑，及薄的樑材質的組合產生可接受的電的損失。 -13- 200848271 迄今，噴墨噴嘴的MEMS製造主要係依賴PECVD ( 電漿強化的化學氣相沉積）及罩幕/触刻步驟來建造一噴 嘴結構。使用PECVD來同時沉積該主動樑411與對該電 極416的連接從MEMS製造的觀點來看是有利的，但無 可避免地導致一薄的，迂迴曲折的連接，這在電流損失方 面是不利的。電流損失在該樑材質不具有最佳的導電性時 回更加惡化。例如，與鋁比較起來，一釩鋁合金具有絕佳 的熱彈性特徵，但導電性則不佳。 PECVD的另一項缺點爲，需要具有傾斜的側壁的一 通孔4 1 8來實施沉積於側壁上。因爲電漿方向性的關係， 所PECVD無法將物質沉積在垂直的側壁上。傾斜的通孔 側壁有數種問題。首先，需要具有傾斜的側壁之光阻支架 (scaffold )，其典型地係藉由使用未對焦的光阻曝光來 達成，這無可避免地會導致精確性的一些喪失。其次，該 噴嘴組件的總足跡（footprint )面積被增加，藉此降低噴 嘴聚集在一起的密度，此一在面積上的增加在噴嘴室的高 度被加大時會被更嚴重地惡化。 減輕在噴嘴組件400內的電流損失的一項償試爲引入 一高度導電性的中間層4 1 7，譬如鈦或鋁，於該電極接點 4 1 6與該主動樑物質4 1 1之間（參見圖1 )。此中間4 1 7 有助於減少一些電流損失，但仍存在有顯著的電流損失。 示於圖1及2中的噴嘴組件的另一項缺點爲，該列印 頭的噴墨面因爲電極通孔418的關係而呈現非平面。該噴 墨面的非平面性會導致結構上的弱點及列印頭維修期間的 -14- 200848271 問題。 有鑑於上述的問題，本案申請人開發出一種製造機械 式熱彎曲噴墨噴嘴組件的方法，其無需依賴P E c V D來形 成從CMOS接點到該致動器的連接。將詳細加以說明的是 ’所得到的噴墨噴嘴組件具有最有最小的電流損失且其平 面的噴墨表面具有一額外的結構上的好處。雖然本發明係 參照一機械式熱彎曲噴墨噴嘴組件爲例來加以體現，但應 被瞭解的是，本發明可被應用到任何用MEMS技術所製 造的噴墨噴嘴種類上。 圖3至26顯示用於圖25及26所示的噴墨噴嘴組件 100的一連串MEM S製造步驟。該ME MS製造的起點爲一 標準的CMOS晶圓，其上具有CMOS元件電路形成在一 矽晶圓的上部上。在MEMS製造處理的結束點，該晶圓 被分切成爲單獨的列印頭積體電路（W )，每一 1C都包 含驅動電路及複數個噴嘴組件。 如圖4及5所示，一基詞1具有一電極2形成在其上 部上。該電極2爲一對相鄰的電極（正極與地極）中的一 個電極用來供應電力至該噴墨噴嘴100的致動器。該等電 極接受來自位在該基材1的上層上之CM0S驅動電路（未 示出）的電力。 示於圖4及5中之另一電極3是用來提供電力至一鄰 近的噴墨曈嘴。大體上，圖中顯不一噴嘴組件的MEMS 製造步驟，該噴嘴組件爲一陣列的噴嘴組件中的一個。下 面的描述聚焦在這些噴嘴組件中的一個噴嘴組件的製造步 -15- 200848271 驟。然而，應被瞭解的是，對應的步驟被同時實施在所有 形成在該晶圓上的噴嘴組件上。在一鄰近的噴嘴組件被部 分地顯示於圖中的地方’這是可被乎略的。因此’電極3 與鄰近的噴嘴組件將於本文中詳細說明。爲了清晰起見’ 某些MEMS製造步驟將不會被顯示在鄰近的噴嘴組件上 〇 現翻到圖3至5，第一系列的MEMS製造步驟開始於 一 CMOS晶圓。一 8微米厚的二氧化矽層一開始被沉積在 基材1上。該二氧化矽的深度界定該噴墨噴嘴之噴嘴室5 的深度。依據所需之噴嘴室5的尺寸，該二氧化矽層的深 度可在4微米至20微米之間，或從6微米到12微米之間 。本發明的一項優點爲，本發明可被用來製造具有相對深 (如大於6微米）的噴嘴室的噴嘴組件。 在沉積該二氧化矽（S i Ο 2 )層之後，它被蝕刻用以界 定將成爲噴嘴室5的側壁之壁4，如圖5所示。圖3中之 該暗色調的罩幕被用來將光阻（未示出）形成圖案，其將 界定此蝕刻。任何適合二氧化矽之標準的非等方向性 DRIE (如’ C4F8/〇2電漿）都可被用於此蝕刻步驟上。再 者’任何可沉積的絕緣物質（如，氮化矽，氮氧化矽，氧 化錦）都可被用來取代該二氧化矽。圖4及5顯示在二氧 化砂沉積與蝕刻步驟的第一系列之後的晶圓。 =系列的步驟中，該噴嘴室5被塡入光阻或聚亞 _ M 6 ’ € %彳乍用係作爲後續沉積步驟的犧牲支架。在準 備下一個沉積步驟時，確保該聚亞醯胺6的頂面與該二氧 •16- 200848271 化矽壁4的頂面共平面是很重要的。確保該二氧化矽壁4 的頂面在CMP之後是乾淨的亦是很重要，且一簡短的清 潔蝕刻可被用來確保可達到以上的要求。 在第三系列的步驟中，該噴嘴室5的室頂件7被形成 ，以及高導電性的連接器柱8被形成下達該等電極2。一 開始，一 1.7微米厚的二氧化矽層被沉積在該聚亞醯胺6 與壁4上。此二氧化矽層界定該噴嘴室5的室頂件4。接 下來，一對通孔（via)藉由使用標準的RDRIE而被形成 在該壁上下至該等電極2。圖8中之暗色調的罩幕被用來 形成光阻（未示出）圖案，該光阻係界定此蝕刻。該鈾刻 係非等方向性蝕刻，使得通孔的側壁較佳地垂直於基材1 的表面。這意謂著任何深度的噴嘴室都可在不影響到該噴 嘴組件在晶圓上的總足跡面積之下被達成。此蝕刻可讓該 對電極2經由通孔被露出。 接下來，通孔藉由使用無電電鍍而被塡入高導電性金 屬，譬如銅。銅無電電鍍方法在此技藝中係屬習知且可輕 易地被加入到一晶圓代工廠中。典型地，一包含銅複合物 的電解質，一乙醛（如，甲醛）及一氫氧化物沉積一銅塗 層於基材的外露表面上。無電電鍍之前通常有一非常薄的 種子金屬（如，鈀）塗層（如，〇·3微米或更薄），其可 催化該電鍍處理。因此，通孔的無電電度之前有一 CVD 之適合的催化劑種子層（如，鈀）的沉積。 在該第三系列步驟的最後一個步驟中，該被沉積的銅 接受CMP處理並停止在該二氧化矽室頂件7上用以提供 -17 - 200848271 一平面的結構。圖9及1 0顯示在此第三系列步驟之後的 噴嘴組件。從圖中可看出的是，在無電銅電鍍期間形成的 銅連接器柱8與各個電極2相遇用以提供直線的導電路徑 上達該室頂件7。此導電路徑沒有彎折或扭結且具有至少 1微米，至少1.5微米，至少2微米，至少2.5微米，或 著少3微米的最小截面直徑。因此，該等銅連接器柱8在 供應電力給該噴墨噴嘴組件內的致動器時有最小的電流損 失。 在第四系列的步驟中，導電金屬墊9被形成，它們被 建構來讓在任何可能的高電阻區域內的電力損失最小化。 這些區域典型地是位在連接器柱8與熱彈性件的接合觸， 以及位在熱彈性件上的任何彎折處。該熱彈性件係在後續 的步驟中形成且金屬墊9的功能在該噴嘴組件以其被完全 形成的狀態加以描述時將可更容易被瞭解。 金屬墊9係藉由沉積0.3微米的鋁層於該室頂件7及 連接器柱8上開始。任何高導電性的金屬（如，鋁，鈦， 等等）都可被使用且被沉積的厚度應爲約0.5微米或更薄 ’才不會對該噴嘴組件的整體平坦度有太嚴重的影響。在 鋁層的沉積之後，一標準的金屬蝕刻（如，C12/BC13 )被 用來界定該金屬墊9。圖11中之該亮色調的罩幕被用將 界定此蝕刻的光阻（未示出）形成圖案。 圖1 2及1 3顯示在該第四系列步驟之後的該噴嘴組件 ’其中金屬墊9被形成在將後續被形成之該熱彈性主動樑 件的預定“彎曲區”內之連接器柱8上及在室頂件7上。爲 -18- 200848271 了清晰起見，金屬墊9並沒有被顯示在圖13 的噴嘴組件上。然而，將可被瞭解的是，在此 有噴嘴組件都是同時被產生的且是依據本文中 造步驟。 在圖14至16所示之第五系列步驟中，一 樑件1 〇被形成在該二氧化矽室頂件7上。部 矽室頂件7因爲被熔接到該主動樑件1 0上所 如一機械式熱彎曲式致動器的下被動樑件1 6 主動樑1 〇與該被動樑1 6所界定。該熱彈性] 可由任何適合的熱彈性材質構成，譬如氮化鈦 鋁合金。如在本案申請人稍早於2002年12月 美國專利申請案第1 1 /607,976號中描述的， 較佳的材質，因爲它們結合了高熱膨脹性，低 氏模數的有利特性。 爲了要該主動樑件1 〇，一 1 .5微米的主動 始藉由標準PECVD被沉積。該樑物質然後使 屬蝕刻加以蝕刻用以界定該主動樑件1 〇。圖] 調的罩幕被來對界定此蝕刻的光阻（未示出） 在完成金屬蝕刻且如圖1 5及1 6所示之後 件1 〇包含部分的噴嘴開口 1 1及一樑元件1 2 過連接器柱8被電氣地連接至正極與電極電極 的樑元件12從一第一（正極）連接器柱的頂 彎曲1 8 0度用以回到一第二（地極）連接器柱 蜒的樑元件結構，如申請人之美國專利 中橫向相鄰 陣列中的所 所描述的製 熱彈性主動 分的二氧化 以其作用係 ，該係由該 芒動樑件1 0 氮化鈦鋁及 4曰提申之 隹凡銘合金是 密度及高楊 樑物質一開 用標準的金 [4中之亮色 形成圖案。 ，該主動樑 ，其端部透 2。該平面 部延伸出並 的頂部。蜿 丨申請案第 -19- 200848271 1 1/60 7,9 76號中描述的，當然亦是在本發明的範圍內。 如在圖15及16中清楚所示的，金屬墊9被設置在促 進電流流入到較高電阻的區域內。一金屬墊9被設置在該 樑元件1 2的一彎曲區域內，且被夾在該主動樑件1 〇與該 被動樑件1 6之間。其它的金屬墊9被設置在連接器柱8 的頂部與樑元件1 2的端部之間。將可被瞭解的是’金屬 墊9可降低在這些區域內的電阻。 在圖1 7至1 9所示的第六系列的步驟中，該二氧化矽 室頂件7被蝕刻用以完全地界定出一噴嘴開口 1 3及該室 頂的活動部分1 4。圖1 7中之暗色調罩幕被用將界定此鈾 刻的光阻（未示出）形成圖案。 如在圖1 8及1 9中清楚所示的，由此蝕刻所界定出來 的該室頂的活動部分1 4包含一熱彎曲式致動器1 5，它本 身是由該主動樑件1 〇與底下的被動樑件1 6所構成的。該 噴嘴開口 1 3亦被界定在該室頂的活動部分1 4上，使得該 噴嘴開口在致動期間與該致動器一起移動。因此，該噴嘴 開口 1 3相對於該活動部分1 4是不動的，美國專利申請案 第1 1 /607,976號中所描述的當然亦是可行的且是在本發 明的範圍內。 一在該室頂的活動部分1 4的附近的周圍間隙1 7將該 室頂的活動部分1 4與不動部分1 8分開來。該間隙1 7可 在致動器1 5的致動期間讓活動部分1 4彎曲到該噴嘴室5 內並朝向該基材1。 在圖20-23所示的第七系列的步驟中，一 3微米厚之 -20- 200848271 可光學地形成圖案的疏水聚合物層1 9被沉積到整個噴嘴 組件上，且被形成圖案用以重新界定該噴嘴開口 1 3。圖 2 0中之暗色調的罩幕被用來將該疏水性聚合物1 9光學地 形成圖案。 使用可光學地形成圖案的聚合物來塗佈該噴嘴組件陣 列在2007年3月12日提申的美國專利第11/685,084號 及2007年4月27日提申的第1 1 /7 40,925號中有詳細的 描述，這兩個申請案的內容藉由此參照而被倂爲本申請案 的內容的一部分。典型地，該疏水性聚合物爲改質聚二甲 基石夕氧院（Polydimethylsiloxane，簡稱 PDMS)，或全贏 聚乙烯（PFPE )。此等聚合物特別有利，因爲它們是可 光學地形成圖案的，具有高疏水性且低楊式模數。 如在上述的美國專利申請案中描述的，包含該疏水性 聚合物之MEMS製造步驟的確實順序是相當有彈性的。 例如，在沉積該疏水性聚合物1 9之後再蝕刻該噴嘴開口 1 3是絕對合理的，且使用該聚合物作爲該罩幕來鈾刻的 罩幕。將可被瞭解的是，在MEMS製造步驟的實際順序 上的改變是在熟習此技藝者的可預見範圍內，且是被包括 在本發明的範圍內。 該疏水性聚合物層1 9實施數種功能。首先，它對位 在該室頂的活動部分1 4的附近的周圍間隙1 7提供一機械 式的密封。該聚合物之低的楊氏模數（<l〇〇〇Mpa )意謂 著它不會顯著地抑制致動器的彎曲，同時防止墨水在致動 期間經由間隙漏出來。其次，該聚合物具有一很高的疏水 -21 - 200848271 性，這可將墨水溢出到相對親水的噴嘴室外並溢到列印頭 的噴墨面2 1上的傾向降至最小。再者，該聚合物的作用 如一保護層一般，這有助於該列印頭的維修。 在圖24-26所示之最終的第八系列步驟中，一供墨渠 道20從該基材1的背側被飩刻穿過該噴嘴室5。圖24中 之暗色調的罩幕被用來將界定此蝕刻的光阻（未示出）形 成圖案。雖然在圖25及26中該供墨渠道20被顯示成與 噴嘴開口 1 3對準，但它亦可偏離該噴嘴開口，如在圖1 中所示的噴嘴組件4 0 0。 在供墨渠道鈾刻之後，被塡入到該噴嘴室5內的該聚 亞醯胺6藉由用氧電漿的去灰（ashing )處理，不論是前 側去灰或是背側去灰，被去除掉用以提供該噴嘴組件1 〇〇 〇 所得到之如圖25與26所示的噴嘴組件1 〇〇相較於圖 1及2所示的噴嘴組件400具有數項優點。第一，噴嘴組 件1 〇 〇在介於致動器的主動樑1 0與電極2之間的連接線 上具有最小的電流損失。銅連接器柱8具有絕佳的導電性 。這是因爲其相對大的截面直徑（>1.5微米）；銅固有的 高導電性；及在該連接線上沒有任何的彎折。因此，銅連 接器柱8可將從該驅動電路到該致動器的電路傳輸最大化 。相反地，在圖1及2中率之噴嘴組件400內的對應連接 線則是相對薄、迂迴曲折且是用與該主動樑4 1 1相同的材 質製成。 第二，連接器柱8乖基材1的表面垂直地延伸出，讓 -22- 200848271 該噴嘴室5的高度能夠在不影響噴嘴組件1 00的總足跡面 積之下被增加。相反地，噴嘴組件400在電極416與主動 樑件4 1 1之間需要有斜度的連接線，使得連接線可用 PECVD來形成。此斜度無可避免地會影響到噴嘴組件400 的總足跡面積，如果噴嘴室40 1的高度將被增加（例如， 用以提供改良的液滴噴出特徵）的話，則這將會是特別不 利的。依據本發明，具有體積相對大的噴嘴室可用小於 5 0微米的噴嘴間距被安排成列。 第三，在電極的區域內沒有凹坑或通孔之下，噴嘴組 件1 〇〇具有平面度高的噴墨面2 1。該噴墨面的平坦性對 於列印頭維修是有利的，因爲它代表對於任何維修裝置而 言是一平滑且可擦抹的表面。再者，不會有微粒被永久地 陷在電極通孔或該噴墨面的其它彎曲特徵結構內的風險。 單然，將可被瞭解的是，本發明已經以舉例的方式加 以描述且細節上的變化可在本發明之由下面的申請專利範 圍所界定的範圍內被達成。 【圖式簡單說明】 圖1爲一熱彎曲致動式噴墨噴嘴組件的側剖面圖，其 具有一薄的，迂迴曲折的連接於一電極與一致動器之間； 圖2爲圖1所示之噴嘴組件的切開立體圖； 圖3爲用於氧化矽壁蝕刻之罩幕； 圖4爲在形成噴嘴室側壁的第一系列步驟之後之部分 作好的噴墨噴嘴組件的側剖面圖； -23- 200848271 圖5爲示於圖4中之部分作好的噴墨噴嘴組件的立體 圖， 圖6爲在用聚亞醯胺塡入噴嘴室的第二系列步驟之後 之部分作好的噴墨噴嘴組件的側剖面匱·； 圖7爲示於圖6中之部分作好的噴墨噴嘴組件的立體 圖； 圖8爲用於通孔蝕刻的罩幕； 圖9爲在連接器柱被形成到達室頂的第三系列步驟之 後之部分作好的噴墨噴嘴組件的側剖面圖； 圖1 〇爲示於圖9中之部分作好的噴墨噴嘴組件的立 體圖； 圖Η爲用於金屬板鈾刻的罩幕； 圖1 2爲在導電金屬板被形成的第四系列步驟之後之 部分作好的噴墨噴嘴組件的側剖面圖； 圖1 3爲示於圖1 2中之部分作好的噴墨噴嘴組件的立 體圖； 圖1 4爲用於主動樑件蝕刻的罩幕； 圖15爲在一熱彎曲式致動器的一主動樑件被形成的 第五系列步驟之後之部分作好的噴墨噴嘴組件的側剖面圖 j 圖1 6爲示於圖1 5中之部分作好的噴墨噴嘴組件的立 體Μ， 圖1 7爲用於氧化矽室頂件蝕刻的罩幕； 圖18爲在一包含該熱彎曲式致動器的活動的室頂部 -24 - 200848271 分被形成的第六系列步驟之後之部分作好的噴墨噴嘴組件 的側剖面圖； 圖1 9爲示於圖1 8中之部分作好的噴墨噴嘴組件的立 體圖， 圖2 0爲用將一可光學地形成圖案的疏水性聚合物形 成圖案的罩幕； 圖2 1爲在該疏水性聚合物層被沉積且被光學地形成 圖案之的第七系列步驟之後之部分作好的噴墨噴嘴組件的 側剖面圖； 圖22爲示於圖2 1中之部分作好的噴墨噴嘴組件的立 體圖， 圖23爲圖22的立體圖，其中底下的MEMS層以虛 線來顯示； 圖24爲用於背側供墨渠道蝕刻的罩幕； 圖2 5爲依據本發明之噴墨噴嘴組件的側剖面圖；及 圖2 6爲圖2 5中所示之噴墨噴嘴組件的切開立體圖。 【主要元件符號說明】 4 〇 〇 :噴嘴組件 4 0 1 :噴嘴室 402 :鈍態化的CMOS層 403 :矽基材 404 :室頂 405 :側壁 -25- 200848271 4 0 6 :墨水入口 407 :供墨渠道 4 0 8 :噴嘴開口 409 :活動部分 4 1 5 :噴嘴邊緣 4 1 0 :熱彎曲式致動器 4 1 1 :主動樑 4 1 2 :被動樑 4 1 6 :電極接點 4 1 8 :通孔 4 1 7 :中間層 2 :電極 1 :基材 1 0 0 :噴墨噴嘴 3 :電極 5 :噴嘴室 4 :二氧化矽（Si02 )壁 6 :聚亞醯胺 7 :室頂件 8 :連接器柱 9 :金屬墊 1 〇 :主動樑件 1 6 :被動樑件 1 2 :樑件 -26 200848271 1 3 :噴嘴開口 1 4 :活動部分 1 7 :間隙 1 8 :不動的部分 1 9 :疏水性聚合物 21 :噴墨面 20 :墨水供應渠道 -27-200848271 IX. Description of the Invention [Technical Field] The present invention relates to an ink jet nozzle assembly and a method of manufacturing an ink jet nozzle assembly. The present invention is primarily intended to reduce the loss of electrical power when power is supplied to the ink jet actuator. [Prior Art] A number of MEMS inkjet nozzles that use thermal bending actuation have been previously described in this application. Thermal bending actuation generally refers to a bending motion associated with another material resulting from thermal expansion of a material having electrical current therethrough. Optionally, the resulting bending motion can be used to eject ink from a nozzle opening through the movement of a paddle or blade that creates a pressure wave within the nozzle chamber. Some representative types of thermally curved inkjet nozzles are exemplified in the patent and patent applications listed in the reference column, the contents of which are hereby incorporated by reference. An ink jet nozzle having a blade disposed in a nozzle chamber and a thermally curved actuator disposed outside the nozzle is disclosed in U.S. Patent No. 6,416,167. The actuator is in the form of a lower active beam that is fused to a conductive material (e.g., titanium nitride) on the upper passive beam of a non-conductive material (e.g., cerium oxide). The actuator is coupled to the blade through an arm that passes through a slot in the wall of the nozzle chamber. When an electric current is passed through the lower main moving beam, the actuator is bent upward, and the pad is thus moved toward a nozzle opening provided on the top of the chamber of the nozzle chamber, thereby ejecting an ink droplet. -4- 200848271 One of the benefits of this design is its simple structure. A disadvantage of this design is that the two blades of the blade work against the rather viscous ink in the nozzle chamber. An ink jet nozzle is disclosed in the applicant's U.S. Patent No. 6,260,953, in which the actuator forms an active chamber top portion of the nozzle chamber. The actuator is in the form of a crucible core material of a conductive material surrounded by a polymeric substance. Upon actuation, the actuator is bent toward the chamber floor of the nozzle chamber, raising the pressure within the chamber and forcing an ink droplet to exit from the nozzle opening provided on the top of the chamber. The nozzle opening is provided on a stationary portion of the top of the chamber. One benefit of this design is that one face of the top portion of the activity needs to work against the relatively viscous ink in the nozzle chamber. A disadvantage of this design is that the conductive elements surrounded by a polymeric material are difficult to fabricate using MEMS processes. An ink jet nozzle comprising a nozzle chamber having a movable chamber top portion having a nozzle opening on the top is disclosed in U.S. Patent No. 6,623,101. The movable roof portion is connected by an arm to a thermally curved actuator disposed outside the nozzle. The actuator is in the form of an upper active beam that is spaced apart from the lower passive beam. By spacing the active beam from the passive beam, the thermal bending efficiency is maximized because the passive beam does not act as a heat sink for the active beam. When an electric current is passed through the upper active beam, the movable ceiling portion on which the nozzle opening is opened is urged to rotate toward the nozzle chamber to eject ink from the nozzle opening. Since the nozzle opening moves together with the ceiling portion, the flight direction of the droplet can be controlled by appropriately changing the shape of the nozzle edge. One benefit of this design is that only one side of the roof portion of the activity must work against the rather viscous ink in the nozzle -5 - 200848271. Another benefit is that the passive beam members are separated to minimize heat loss. This separation of the active and passive beam members will make the structure robust. In all MEMS inkjet nozzle designs, there is a need to minimize this. In the case where the nozzle design is the primary cause of electrical losses, it is particularly important to minimize the loss of electrical current, a relatively long distance between the actuator and a CMOS supplying current to the actuator. It will make the loss of electricity more serious. Furthermore, or twisting the current path will also make the loss of electricity more serious. Generally, the actuator material in the ink jet nozzle is selected from a material that satisfies several requirements. In mechanical hot bending actuated nozzles, these elements include electrical conductivity, coefficient of thermal expansion 'Yang modulus in the example of a hot bubble forming inkjet nozzle' which include oxidation resistance, burst resistance and the like. Thus the choice of the material to be understood is generally a compromise of multiple characteristics, and the actuation does not necessarily have the best conductivity. In the case where the actuator material itself is electrically conductive, the loss of electricity in the nozzle assembly is minimized. Finally, any improvements in nozzle design should be compatible with standard processes. For example, some materials are not compatible with MEMS processes because they can cause contamination at the fab. From the foregoing, it will be appreciated that there is a need for 'inkjet nozzles and manufacturing improvements' to reduce the loss of electricity to droplet ejection that provides a more efficient printhead. For the loss of electricity, the initiative and the shortcomings are dynamic. The loss of electricity is unfavorable. For example, electrodes, bendable species, and so on. Conductivity is the design of the mechanically hot-blow-actuated inkjet nozzle that is the second-class MEMS capacitor with the smallest design and the smallest design and is deteriorated due to the inherent appearance of the nozzle design of -6 - 200848271. There are special needs for manufacturing improvements. SUMMARY OF THE INVENTION In a first aspect of the invention, the present invention provides a method of forming an electrical connection between an electrode and an actuator within an inkjet nozzle assembly, the method comprising the steps of: a) providing a substrate having a driving circuit layer, the driving circuit comprising the electrode for connecting to the actuator; (b) forming an insulating material wall on the electrode; (c) forming on at least the wall a via that exposes the electrode; (d) using electroless plating to pour a conductive material into the via to provide a connector post; and (e) forming at least a portion of the actuator A connector post for providing electrical connection between the actuator and the electrode. The upper ground is selected such that the distance between the actuator and the electrode is at least 5 microns. Selecting the upper layer, the driving circuit layer is a CMOS layer of a substrate. Selecting the upper layer, the drive circuit includes a pair of electrodes for each of the ink jet nozzle assemblies, each electrode being connected to the actuator by a respective connector post, the insulating material wall being oxidized矽 constitute. The upper hole is selected to have a side wall perpendicular to one side of the substrate. -7- 200848271 Select the upper hole, the through hole has a minimum cross-sectional diameter of 1 micron or more 〇 Select the upper ground, the conductive material is metal. Selecting the upper layer, the conductive material is copper. In another aspect, a method is provided, the method further comprising the step of: depositing a catalyst layer on the base of the via prior to the electroless plating. The upper layer is selected and the catalyst is palladium. The upper conductive material is selected to be planarized by chemical mechanical planarization prior to forming the actuator. Optionally, the actuator is a thermally curved actuator comprising a planar active beam member that mechanically cooperates with a planar passive beam member. Optionally, the thermal bending actuator at least partially defines a roof of the chamber for the nozzle chamber of the ink jet nozzle assembly. The upper insulator is selected to define a sidewall of the nozzle chamber. Selecting the upper layer, step (e) involves depositing an active beam material onto a driven beam material. The upper beam is selected such that the active beam member of the active beam material extends from the top of the connector post to a plane perpendicular to the column. In another aspect, the present invention provides a method further comprising the steps of: depositing a first metal pad on top of the connector post prior to deposition of the active beam material, the first metal pad being constructed Promote current flow from the -8 - 200848271 connector post to the active beam. Optionally, the planar active beam member comprises a curved or meandering beam member having a first end that is placed over a first connector post and a second end that is placed in a Above the second connector post, the first and second connector posts are adjacent to one another. In another aspect, the present invention provides a method further comprising the steps of: depositing one or more second metal pads on the passive beam material prior to deposition of the active beam material, the second metal pad being Placed to promote current flow into the curved region of the beam member. In a second aspect, the present invention provides a printhead integrated circuit comprising a substrate having a plurality of ink jet nozzle assemblies formed on a surface of the substrate, the substrate having a drive circuit for supplying electricity To the nozzle assemblies, each nozzle assembly includes: a nozzle chamber for containing ink, the nozzle chamber having a nozzle opening defined therein; an actuator for ejecting ink through the nozzle opening; a pair disposed thereon An electrode on the surface of the substrate, the electrodes being electrically connected to the drive circuit; and a pair of connector posts, each connector electrode electrically connecting a further electrode to the actuator, wherein each A connector post extends linearly from the individual electrodes to the actuator. Selecting the upper ground 'each connector post is perpendicular to the surface of the substrate -9-200848271. The uppermost distance between the actuator and the electrodes is selected to be at least 5 microns. Selecting the upper ground 'The minimum cross-sectional diameter of the connector posts is 2 microns or greater. Optionally, the nozzle assemblies are arranged in a plurality of nozzle rows that extend longitudinally along the substrate. Selecting the upper ground, the distance between adjacent nozzle openings in a nozzle row is less than 50 microns. Optionally, the actuator is a thermally curved actuator comprising a planar active beam member that mechanically cooperates with a planar passive beam member. Optionally, the hot bending actuator at least partially defines a roof for the nozzle chamber of the ink jet nozzle assembly, the nozzle opening being defined on top of the chamber. Selecting the upper floor, an insulating material wall defines the side wall of the nozzle chamber. The upper beam is selected to be electrically connected to the top of the connector posts. A top portion is selected and a portion of the active beam member is placed over the top of the connector posts. In another aspect, the present invention provides a column head integrated circuit further comprising a first metal pad placed between the top of each connector post and the active beam member, each first gapped metal The pads are all constructed to facilitate current flow from an 'individual connector post to the active build. The upper beam is selected from the active beam material selected from the group consisting of: aluminum alloy; nitrogen-10-200848271 titanium and titanium aluminum nitride. The upper beam is selected from the vanadium aluminum alloy. Selecting the upper ground, the planar active beam member includes a beam member including a curved or meandering member having a first end that is placed over a first connector post and a second end that is placed Above the second connector post, the first and second connector posts are adjacent one another. In another aspect, the invention provides a printhead integrated circuit that further includes at least one second metal pad that is placed to facilitate current flow into a curved region of the beam member. In another aspect, the invention provides a printhead integrated circuit that further comprises an outer surface layer of a hydrophobic polymer on top of the chamber. The upper surface layer is selected to define a planar ink jet surface of the printhead integrated circuit that does not have a substantially planar configuration other than the nozzle openings. Optionally, the hydrophobic polymer mechanically seals a gap between the thermally curved actuator and the nozzle chamber. In another aspect, the present invention provides a pagewidth inkjet printhead comprising a plurality of inkjet head integrated circuits, the inkjet head integrated circuit comprising a substrate having a plurality of inkjet nozzle assemblies formed On the surface of the substrate, the substrate has a drive circuit for supplying power to the nozzle assemblies, each nozzle assembly comprising: a nozzle chamber for containing ink, the nozzle chamber having a nozzle defined therein An actuator for ejecting ink through the nozzle opening; -11. 200848271 a pair of electrodes disposed on the surface of the substrate, the electrodes being electrically connected to the driving circuit; and a pair of connector posts, Each connector post electrically connects an additional electrode to the actuator, wherein each connector post extends linearly from the individual electrodes to the actuator. [Embodiment] Figures 1 and 2 show a nozzle assembly as described in U.S. Patent Application Serial No. 11/607,976, the entire disclosure of which is incorporated herein by Be shackled in this article. The nozzle assembly 400 includes a nozzle chamber 401 formed on an inactive CMOS layer 402 of a substrate 4〇3. The nozzle chamber is defined by a chamber top 404 and a side wall 405 extending from the top of the chamber to the passivated C Ο M S layer 420. The ink is supplied to the nozzle chamber 401 by an ink inlet 406 in fluid communication with the ink supply channel 407, which receives the ink from the substrate 403. The ink is ejected from the nozzle chamber 401 by a nozzle opening 408 defined on the chamber top 4 〇 4 . The nozzle opening 408 is offset from the ink inlet 406. As best seen in Figure 2, the roof 4 〇 4 has a movable portion 409 which defines a substantial portion of the total area of the roof. The nozzle opening 408 and the nozzle edge 415 are defined on the movable portion 409 such that the nozzle opening moves with the nozzle edge and the movable portion. The movable portion 409 is defined by a thermally curved actuator 410 having a planar upper active beam 411 and a lower passive beam 4 1 2 of -12-200848271. The active beam 41 is connected to a pair of electrode contacts (positive and ground). Electrode 416 is coupled to a drive circuit in the COMS layer. When it is desired to eject an ink droplet from the nozzle chamber 410, a current flows through the active beam 4 1 1 between the two contacts 4 16 . The drive beam 4 1 1 is rapidly heated by the current and expands relative to the passive beam 4 1 2 , thereby causing the actuator 410 (which defines the movable portion 409 of the chamber roof 404 ) to bend downwardly toward the substrate 403 . This movement of the actuator 410 causes ink to be ejected from the nozzle opening by the rapidly increasing pressure within the nozzle chamber 40 1 . When the current is stopped, the movable portion 409 of the chamber top 404 can be returned to its rest position, which can draw ink from the inlet 406 into the nozzle chamber 401 for the next ink jet. In the nozzle design shown in Figures 1 and 2, the chamber top 404 defining at least a portion of the nozzle 401 is advantageous for the actuator 410. This not only simplifies the overall design and manufacture of the nozzle assembly 400, but also provides a higher ink jet efficiency since only one face of the actuator 410 must operate against the relatively viscous ink within the nozzle chamber. In contrast, a nozzle assembly having an actuator pad disposed within the interior of the nozzle is less efficient because both sides of the actuator must operate with ink in the chamber. However, in the structure in which the actuator 410 at least partially defines the chamber roof 04 of the chamber 401, the electrode 4 1 1 that is indirectly connected to the active beam 41 1 and the active electrode 4 1 1 is inevitable. There is a relatively long distance between them. The relatively long distance between the electrode 4 16 and the actuator 4 10 , the meandering current path, and the combination of the thin beam material results in an acceptable electrical loss. -13- 200848271 To date, MEMS fabrication of inkjet nozzles has relied primarily on PECVD (plasma-enhanced chemical vapor deposition) and mask/touch steps to build a nozzle structure. The use of PECVD to simultaneously deposit the active beam 411 with the connection to the electrode 416 is advantageous from the point of view of MEMS fabrication, but inevitably results in a thin, tortuous connection which is disadvantageous in terms of current loss. . The current loss is further aggravated when the beam material does not have the best conductivity. For example, vanadium-aluminum alloys have excellent thermoelastic properties compared to aluminum, but conductivity is poor. Another disadvantage of PECVD is that a through hole 4 1 8 having inclined sidewalls is required to be deposited on the sidewall. Because of the directionality of the plasma, PECVD cannot deposit material on vertical sidewalls. There are several problems with the side walls of the slanted through holes. First, a scaffold with slanted sidewalls is required, typically achieved by exposure using unfocused photoresist, which inevitably results in some loss of accuracy. Second, the total footprint area of the nozzle assembly is increased, thereby reducing the density at which the nozzles are brought together, and this increase in area is more severely degraded as the height of the nozzle chamber is increased. One attempt to mitigate the current loss in the nozzle assembly 400 is to introduce a highly conductive intermediate layer 141, such as titanium or aluminum, between the electrode contact 416 and the active beam material 4 1 1 . (See Figure 1). This intermediate 4 1 7 helps to reduce some current losses, but there is still significant current loss. Another disadvantage of the nozzle assembly shown in Figures 1 and 2 is that the ink jet face of the printhead is non-planar due to the relationship of the electrode vias 418. The non-planarity of the ink jet surface can cause structural weaknesses and problems during the printhead maintenance period -14-200848271. In view of the foregoing, the applicant of the present invention has developed a method of manufacturing a mechanical thermal bending inkjet nozzle assembly that does not rely on P E V V D to form a connection from a CMOS junction to the actuator. It will be explained in detail that the resulting ink jet nozzle assembly has the least current loss and its planar ink jet surface has an additional structural advantage. Although the invention has been described with reference to a mechanical thermal bending inkjet nozzle assembly, it will be appreciated that the invention can be applied to any type of inkjet nozzle fabricated using MEMS technology. Figures 3 through 26 show a series of MEM S fabrication steps for the ink jet nozzle assembly 100 shown in Figures 25 and 26. The starting point for the ME MS fabrication is a standard CMOS wafer with CMOS component circuitry formed on top of a wafer. At the end of the MEMS fabrication process, the wafer is slit into individual printhead integrated circuits (W), each of which contains a drive circuit and a plurality of nozzle assemblies. As shown in Figures 4 and 5, a basic term 1 has an electrode 2 formed on its upper portion. The electrode 2 is an electrode of a pair of adjacent electrodes (positive electrode and ground) for supplying electric power to the actuator of the ink jet nozzle 100. The electrodes receive power from a CMOS drive circuit (not shown) located on the upper layer of the substrate 1. The other electrode 3 shown in Figures 4 and 5 is for providing power to a nearby ink jet nozzle. In general, the MEMS fabrication steps of the nozzle assembly are shown in the figures, which is one of an array of nozzle assemblies. The following description focuses on the manufacturing steps of one of these nozzle assemblies -15-200848271. However, it should be understood that the corresponding steps are performed simultaneously on all of the nozzle assemblies formed on the wafer. Where an adjacent nozzle assembly is partially shown in the figure 'this can be omitted. Thus 'electrode 3 and adjacent nozzle assemblies will be described in detail herein. For the sake of clarity, some MEMS fabrication steps will not be shown on adjacent nozzle assemblies. Turning to Figures 3 through 5, the first series of MEMS fabrication steps begins with a CMOS wafer. An 8 μm thick ceria layer was initially deposited on the substrate 1. The depth of the cerium oxide defines the depth of the nozzle chamber 5 of the ink jet nozzle. The cerium oxide layer may have a depth of between 4 microns and 20 microns, or between 6 microns and 12 microns, depending on the size of the desired nozzle chamber 5. An advantage of the present invention is that the present invention can be used to make nozzle assemblies having relatively deep (e.g., greater than 6 microns) nozzle chambers. After depositing the layer of cerium oxide (S i Ο 2 ), it is etched to define the wall 4 which will become the sidewall of the nozzle chamber 5, as shown in FIG. The dark shade mask of Figure 3 is used to pattern a photoresist (not shown) that will define this etch. Any non-isotropic DRIE (e.g., 'C4F8/〇2 plasma) suitable for the standard of cerium oxide can be used for this etching step. Further, any depositable insulating material (e.g., tantalum nitride, niobium oxynitride, bismuth oxide) can be used in place of the cerium oxide. Figures 4 and 5 show wafers after the first series of dioxide sand deposition and etching steps. In the series of steps, the nozzle chamber 5 is immersed in a photoresist or poly _M 6 '% 彳乍 彳乍 as a sacrificial support for subsequent deposition steps. It is important to ensure that the top surface of the polyamidoamine 6 is coplanar with the top surface of the dioxin 16-200848271 quince wall 4 when preparing the next deposition step. It is also important to ensure that the top surface of the ceria wall 4 is clean after CMP, and a brief clean etch can be used to ensure that the above requirements are met. In the third series of steps, the chamber top member 7 of the nozzle chamber 5 is formed, and the highly conductive connector post 8 is formed to be lowered to the electrodes 2. Initially, a 1.7 micron thick layer of ruthenium dioxide was deposited on the polyamine 6 and wall 4. This ruthenium dioxide layer defines the roof element 4 of the nozzle chamber 5. Next, a pair of vias are formed on the wall up to the electrodes 2 by using standard RDRIE. The shade of the mask in Figure 8 is used to form a photoresist (not shown) pattern that defines the etch. The uranium is etched non-equally etched such that the sidewalls of the vias are preferably perpendicular to the surface of the substrate 1. This means that any depth of the nozzle chamber can be achieved without affecting the total footprint of the nozzle assembly on the wafer. This etching allows the pair of electrodes 2 to be exposed through the via holes. Next, the via is infused with a highly conductive metal such as copper by using electroless plating. Copper electroless plating methods are well known in the art and can be easily incorporated into a foundry. Typically, an electrolyte comprising a copper complex, an acetaldehyde (e.g., formaldehyde) and a hydroxide, is deposited on a exposed surface of the substrate. There is usually a very thin seed metal (e.g., palladium) coating (e.g., 3 microns or less) prior to electroless plating that catalyzes the plating process. Therefore, the electrolessness of the via is preceded by the deposition of a suitable catalyst seed layer (e.g., palladium) of CVD. In the final step of the third series of steps, the deposited copper is subjected to a CMP process and is stopped on the ceria chamber top member 7 to provide a -17 - 200848271 plane structure. Figures 9 and 10 show the nozzle assembly after this third series of steps. As can be seen from the figure, the copper connector posts 8 formed during electroless copper plating meet the respective electrodes 2 to provide a linear conductive path to the chamber top member 7. The conductive path is not bent or kinked and has a minimum cross-sectional diameter of at least 1 micrometer, at least 1.5 micrometers, at least 2 micrometers, at least 2.5 micrometers, or less than 3 micrometers. Thus, the copper connector posts 8 have minimal current loss when supplying power to the actuators within the ink jet nozzle assembly. In the fourth series of steps, conductive metal pads 9 are formed which are constructed to minimize power loss in any possible high resistance region. These regions are typically located in engagement with the connector post 8 and the thermoelastic member, as well as at any bends on the thermoelastic member. The thermoelastic member is formed in a subsequent step and the function of the metal pad 9 will be more easily understood when the nozzle assembly is described in a state in which it is completely formed. The metal pad 9 is started by depositing a 0.3 micron aluminum layer on the chamber top member 7 and the connector post 8. Any highly conductive metal (eg, aluminum, titanium, etc.) can be used and deposited to a thickness of about 0.5 microns or less to not have too much impact on the overall flatness of the nozzle assembly. . A standard metal etch (e.g., C12/BC13) is used to define the metal pad 9 after deposition of the aluminum layer. The brightly colored mask of Figure 11 is patterned with a photoresist (not shown) that defines this etch. Figures 1 2 and 13 show the nozzle assembly 'after the fourth series of steps' wherein the metal pad 9 is formed on the connector post 8 in a predetermined "bending zone" of the thermoelastic active beam member to be subsequently formed. And on the top member 7. For the sake of clarity -18-200848271, the metal pad 9 is not shown on the nozzle assembly of Figure 13. However, it will be appreciated that there are nozzle assemblies all of which are produced simultaneously and in accordance with the fabrication steps herein. In the fifth series of steps shown in Figs. 14 to 16, a beam member 1 is formed on the ceria chamber top member 7. The chamber top member 7 is defined by the lower passive beam member 16 and the passive beam 16 as it is welded to the active beam member 10, such as a mechanical hot bending actuator. The thermoelasticity can be made of any suitable thermoelastic material, such as a titanium nitride aluminum alloy. Preferred materials are described in the applicant's earlier application of U.S. Patent Application Serial No. 1 1/607,976, which is incorporated herein by reference. In order for the active beam member to be 〇, a 1.5 micron active is initially deposited by standard PECVD. The beam material is then etched to etch the active beam member 1 〇. The mask is adjusted to define the photoresist (not shown). After the metal etching is completed and as shown in FIGS. 15 and 16, the part 1 of the nozzle opening 1 1 and a beam element 1 are included. 2 The connector element 8 is electrically connected to the positive electrode and the electrode electrode. The beam element 12 is bent from the top of a first (positive) connector column by 180 degrees to return to a second (ground) connector column. The beam element structure of the crucible, as described in the laterally adjacent array of the Applicant's U.S. patent, the electrothermally active active fractionation of the system of action, the system consisting of the beam member 10 0 titanium aluminum nitride And the 曰 隹 隹 隹 隹 隹 隹 隹 隹 隹 隹 隹 隹 隹 隹 隹 隹 隹 隹 隹 隹 隹 隹 隹 隹 隹 隹 隹 隹 隹 隹The active beam has its end transparent. The flat portion extends out of the top of the joint. It is of course also within the scope of the invention to describe it in the application -19-200848271 1 1/60 7,9 76. As clearly shown in Figures 15 and 16, the metal pad 9 is placed in a region where the current is induced to flow into the higher resistance. A metal pad 9 is disposed in a curved region of the beam member 12 and is sandwiched between the active beam member 1 and the passive beam member 16. Other metal pads 9 are provided between the top of the connector post 8 and the end of the beam member 12. It will be appreciated that the 'metal pad 9' can reduce the resistance in these areas. In the sixth series of steps shown in Figures 17 through 19, the ceria chamber top member 7 is etched to completely define a nozzle opening 13 and the movable portion 14 of the chamber. The dark tone mask of Figure 17 is patterned with a photoresist (not shown) that defines this uranium engraving. As clearly shown in Figures 18 and 19, the movable portion 14 of the chamber defined by the etching comprises a thermally curved actuator 15 which itself is the active beam member 1 It is composed of a passive beam member 16 underneath. The nozzle opening 13 is also defined on the movable portion 14 of the chamber top such that the nozzle opening moves with the actuator during actuation. Thus, the nozzle opening 13 is immovable relative to the movable portion 14 and is of course also possible and within the scope of the present invention as described in U.S. Patent Application Serial No. 1 1/607,976. A peripheral gap 17 near the movable portion 14 of the top of the chamber separates the movable portion 14 of the roof from the stationary portion 18. This gap 17 allows the movable portion 14 to be bent into the nozzle chamber 5 and towards the substrate 1 during actuation of the actuator 15. In the seventh series of steps shown in Figures 20-23, a 3 micron thick -20-200848271 optically patterned hydrophobic polymer layer 19 is deposited over the entire nozzle assembly and patterned for Redefine the nozzle opening 13 . A dark-tone mask in Fig. 20 is used to optically pattern the hydrophobic polymer 19. U.S. Patent No. 11/685,084, filed on March 12, 2007, and No. 1 1/7 40, 925, filed on Apr. 27, 2007, which is incorporated herein by reference. A detailed description of these two applications is hereby incorporated by reference in its entirety into the content of the application. Typically, the hydrophobic polymer is a modified polydimethylsiloxane (PDMS) or a full-win polyethylene (PFPE). These polymers are particularly advantageous because they are optically patternable, have a high hydrophobicity and have a low Young's modulus. The exact sequence of MEMS fabrication steps comprising the hydrophobic polymer is quite flexible, as described in the aforementioned U.S. Patent Application. For example, it is absolutely reasonable to etch the nozzle opening 13 after depositing the hydrophobic polymer 19, and the polymer is used as a mask for the uranium engraving of the mask. It will be appreciated that variations in the actual order of the MEMS fabrication steps are within the foreseeable scope of those skilled in the art and are included within the scope of the present invention. The hydrophobic polymer layer 19 performs several functions. First, it provides a mechanical seal to the peripheral gap 17 in the vicinity of the movable portion 14 of the roof. The low Young's modulus (< l 〇〇〇 Mpa ) of the polymer means that it does not significantly suppress the bending of the actuator while preventing the ink from leaking out through the gap during actuation. Second, the polymer has a very high hydrophobicity of -21 - 200848271, which minimizes the tendency of the ink to spill out of the relatively hydrophilic nozzle and spill over the inkjet face 21 of the printhead. Moreover, the polymer acts as a protective layer which aids in the maintenance of the printhead. In the final eighth series of steps shown in Figures 24-26, an ink supply channel 20 is etched through the nozzle chamber 5 from the back side of the substrate 1. The shade of the mask in Figure 24 is used to pattern the photoresist (not shown) defining this etch. Although the ink supply channel 20 is shown aligned with the nozzle opening 13 in Figures 25 and 26, it can also be offset from the nozzle opening, such as the nozzle assembly 400 shown in Figure 1. After the uranium entrainment of the ink supply channel, the polyamidoamine 6 that is intruded into the nozzle chamber 5 is treated by ashing with oxygen plasma, whether it is ash on the front side or ash on the back side. The nozzle assembly 1 shown in Figures 25 and 26 obtained by removing the nozzle assembly 1 has several advantages over the nozzle assembly 400 shown in Figures 1 and 2. First, the nozzle assembly 1 〇 具有 has minimal current loss on the connection between the active beam 10 of the actuator and the electrode 2. The copper connector post 8 has excellent electrical conductivity. This is because of its relatively large cross-sectional diameter (> 1.5 microns); the inherent high electrical conductivity of copper; and no bending on the connecting line. Thus, the copper connector post 8 maximizes circuit transmission from the drive circuit to the actuator. Conversely, the corresponding connecting lines in the nozzle assembly 400 of Figures 1 and 2 are relatively thin, meandering, and are made of the same material as the active beam 41. Second, the surface of the connector post 8乖 substrate 1 extends vertically so that the height of the nozzle chamber 5 of -22-200848271 can be increased without affecting the total footprint of the nozzle assembly 100. Conversely, the nozzle assembly 400 requires a tapered connecting line between the electrode 416 and the active beam member 41, such that the connecting line can be formed by PECVD. This slope will inevitably affect the total footprint of the nozzle assembly 400, which would be particularly disadvantageous if the height of the nozzle chamber 40 1 would be increased (e.g., to provide improved droplet ejection characteristics). of. In accordance with the present invention, nozzle chambers having a relatively large volume can be arranged in columns with a nozzle pitch of less than 50 microns. Third, the nozzle assembly 1 has an ink jet surface 21 having a high degree of flatness without a pit or a through hole in the region of the electrode. The flatness of the inkjet face is advantageous for printhead maintenance because it represents a smooth and wipeable surface for any service device. Moreover, there is no risk that the particles will be permanently trapped within the electrode vias or other curved features of the inkjet face. It is to be understood that the present invention has been described by way of example and the details of the details of the invention can be made within the scope of the invention as defined by the following claims. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side cross-sectional view of a thermal bending actuated ink jet nozzle assembly having a thin, meandering connection between an electrode and an actuator; FIG. 2 is FIG. 3 is a cutaway perspective view of the nozzle assembly; FIG. 3 is a mask for oxidizing the wall etching; FIG. 4 is a side cross-sectional view of the portion of the inkjet nozzle assembly after the first series of steps of forming the sidewall of the nozzle chamber; 23- 200848271 FIG. 5 is a perspective view of a portion of the ink jet nozzle assembly shown in FIG. 4, and FIG. 6 is a partially completed ink jet nozzle after the second series of steps of breaking the nozzle chamber with polyamidoamine. Figure 7 is a perspective view of a portion of the ink jet nozzle assembly shown in Figure 6; Figure 8 is a mask for through hole etching; Figure 9 is a connector column formed into the chamber A side cross-sectional view of a portion of the ink jet nozzle assembly after the third series of steps; Fig. 1 is a perspective view of the ink jet nozzle assembly shown in Fig. 9; Engraved cover; Figure 1 2 is the quaternary system formed on the conductive metal plate A side cross-sectional view of a portion of the ink jet nozzle assembly after the step; FIG. 13 is a perspective view of the portion of the ink jet nozzle assembly shown in FIG. 12; FIG. 14 is a cover for active beam etching. Figure 15 is a side cross-sectional view of a portion of the ink jet nozzle assembly after a fifth series of steps in which an active beam member is formed in a thermally curved actuator. Figure 16 is shown in Figure 15. Part of the stencil of the inkjet nozzle assembly is shown in Fig. 17. Fig. 17 is a mask for etching the enamel chamber top member; Fig. 18 is a movable chamber top portion-24 containing the hot bending actuator. 200848271 A side cross-sectional view of a portion of the ink jet nozzle assembly after the sixth series of steps formed; FIG. 19 is a perspective view of the ink jet nozzle assembly shown in FIG. 18, FIG. A mask formed by patterning an optically patternable hydrophobic polymer; FIG. 21 is a portion of the seventh series of steps after the hydrophobic polymer layer is deposited and optically patterned. Side sectional view of the ink jet nozzle assembly; Fig. 22 is a portion shown in Fig. 21. FIG. 23 is a perspective view of the inkjet nozzle assembly, FIG. 23 is a perspective view of FIG. 22, wherein the bottom MEMS layer is shown by a broken line; FIG. 24 is a mask for etching the back side ink supply channel; FIG. A side cross-sectional view of the ink jet nozzle assembly; and Fig. 26 is a cutaway perspective view of the ink jet nozzle assembly shown in Fig. 25. [Main component symbol description] 4 〇〇: Nozzle assembly 4 0 1 : Nozzle chamber 402: Passivated CMOS layer 403: 矽 Substrate 404: Room top 405: Side wall - 25 - 200848271 4 0 6 : Ink inlet 407: Ink supply channel 4 0 8 : nozzle opening 409 : movable part 4 1 5 : nozzle edge 4 1 0 : thermal bending actuator 4 1 1 : active beam 4 1 2 : passive beam 4 1 6 : electrode contact 4 1 8 : through hole 4 1 7 : intermediate layer 2 : electrode 1 : substrate 1 0 0 : ink jet nozzle 3 : electrode 5 : nozzle chamber 4 : cerium oxide (SiO 2 ) wall 6 : polytheneamine 7 : chamber top Item 8: Connector post 9: Metal pad 1 〇: Active beam member 1 6 : Passive beam member 1 2 : Beam member -26 200848271 1 3 : Nozzle opening 1 4 : Active part 1 7 : Clearance 1 8 : Immovable part 1 9 : Hydrophobic polymer 21 : inkjet surface 20 : ink supply channel -27-