201020123 九、發明說明 【發明所屬之技術領域】 本發明有關印表機及特別是噴墨列印頭之領域。其主 要被開發至改善高解析度列印頭中之列印品質及可靠性。 【先前技術】 很多不同之列印型式已被發明，其大數量目前正在使 @ 用°習知之列印形式具有各種用於以相關標記媒體標記該 列印媒體之方法。一般使用之列印形式包括偏置列印、雷 射列印及拷貝裝置、點矩陣型撞擊式印表機、熱感紙印表 機、錄影器、熱蠟式印表機、染料昇華印表機及該控制液 滴式與連續供應式雨者噴墨式印表機。當考慮成本、速率 、品質、可靠性、結構及操作之簡單性等時，每一型式之 印表機具有它們自己之優點及問題。 近年來，噴墨式列印之領域已由於其之不貴及多用途 φ 之本質主要變得越發受歡迎，其中每一個別之墨水圖素係 源自一或多個墨水噴嘴。 在噴墨式列印上之很多不同技術已被發明。對於該領 域之觀察，可參考輸出硬拷貝裝置，編者R Dubeck及S Sherr，第207-220頁（1988年）以J Moore之名所發表之文 章，“非撞擊式列印：導論及歷史透視”。 噴墨式印表機本身有很多不同型式。噴墨式列印中之 墨水的連續液流之利用率可追溯到至少1929年就出現， 其中以Hansell之名的美國專利第1,941,001號揭示連續 201020123 液流之靜電噴墨式列印的一簡單形式。 以史威特之名的美國專利第3,596,275號亦揭示一連 續噴墨式列印之製程’包括該步驟，其中該噴墨式液流係 藉由一高頻靜電場所調節，以便造成點滴分離。此技術仍 然被數個製造廠所利用’包括Elmjet及Scitex(亦看以史 威特等人之名的美國專利第3,373，437號）。 壓電噴墨式印表機係亦一般利用之噴墨列印裝置的一 形式。壓電系統被Kyser等人揭示於利用隔膜模式之操作 的美國專利第3,946,3 98號（1 970年）中；被Zolten揭示於 美國專利第3,683,2 1 2號（1 970年）中，其揭示壓電晶體之 擠壓模式操作；Stemme於美國專利第3,747，120號（1972 年）中揭示壓電操作的一彎曲模式；Howkins於美國專利 第4,459,60 1號中揭示該噴墨式液流的一壓電推動模式致 動；及Fischbeck於美國專利第4,584,590號中揭示壓電 傳感器元件之剪切模式類型。 近來，熱噴墨式列印已變成非常受歡迎之噴墨式列印 類型。 該等噴墨式列印技術包括那些由Endo等人在英國專 利第GB 2，007,1 62號（1979年）及Vaught等人於美國專利 第4,490,72 8號中所揭示者。前述兩參考案揭示噴墨式列 印技術，其依靠一電熱致動器之激活，其導致在受限制的 空間、諸如噴嘴中之氣泡的建立，藉此造成墨水由一連接 至該被限制空間之孔口射出至相關之列印媒體上。利用該 電熱致動器之列印裝置被諸如佳能及惠普之製造商所製成 -6- 201020123 如能由該前面看見，很多不同型式之列印技術係可用 的。理想上，一列印技術將具有許多想要之屬性。這些包 括不貴之結構及操作、高速操作、安全及連續之長期操作 等。每一技術可於成本、速率、品質、可靠性、用電、結 構操作之簡單性、耐用性及消耗品之區域中具有它們自己 之優點及缺點。 Φ 本申請人已敘述過多之噴墨列印頭，該等列印頭係利 用微機電系統（MEM S)技術所製成。如於該申請人之稍早 的美國申請案第 11/685,084; 11/763,443;及 11/763,440 號中所敘述，其內容係以引用的方式倂入本文中，一 MEMS噴墨列印頭可包括一具有活動部分之噴嘴板。每一 活動部分典型具有一界定在其中之噴嘴開口，以致該活動 部分之致動導致墨水由該列印頭射出。 譬如與傳統之熱氣泡成形列印頭比較，此型式之列印 • 頭的優點係射出一墨水點滴所需之能量爲小的。該申請人 已經事先敘述特定之致動器設計與補充之致動方法如何由 此等列印頭提供高效率之點滴射出（例如，看美國申請案 第1 1/607,976及12/239,81 4號，其內容係以引用的方式 倂入本文中）。 然而，具有•活動噴嘴•列印頭的一問題係它們在該列 印頭的活動部分及固定不動部分之間需要一良好之流體密 封。墨水應僅只被射出穿過該噴嘴開□，且不應由密封件 漏出。如果該活動部分及該固定不動部分間之距離係小的 201020123 ，則表面張力可保留在噴嘴室內側之墨水。然而，當作一 流體密封的墨水表面張力之使用係有問題的，且通常不能 提供一可靠之密封，尤其是如果在噴嘴室內側之墨水歷經 壓力突波。 於該申請人之稍早申請案第1 1/685,084; 1 1/763,443 :及1 1/763,440號中，已敘述有一用於噴嘴板之活動部 分的機械式密封之製造方法。典型地，聚二甲基矽氧烷 (PDMS)之撓性層係塗覆在該噴嘴板上方，其用作該列印 頭的活動部分及固定不動部分間之密封膜。再者，該 PDMS層提供一疏水性墨水射出表面，其以列印頭射流技 術及最後列印品質之觀點係亦極想要的。 其將想要的是對於具有活動噴嘴之噴墨列印頭提供改 良之機械式密封。其將特別想要的是提供在該列印頭之整 個效率上具有最小衝擊的有效機械式密封。 【發明內容】 於第一態樣中，本發明提供一噴墨列印頭用之噴嘴總 成，該噴嘴總成包括： 一噴嘴室，其包括一頂板，在該頂板中界定一噴 嘴開口，該頂板包括可相對一固定不動部分移動之活動部 分，使得該活動部分相對該固定不動部分之移動造成墨水 經過該噴嘴開口射出； 一致動器，用於相對該固定不動部分移動該活動 部分；及 -8 - 201020123 一密封構件，其被組構成爲一跨越該活動部分及 該固定不動部分之間的橋接件。 選擇性地，該密封構件係由聚合體材料所組成。 選擇性地，該聚合體材料係由聚二甲基矽氧烷 (PDMS)所組成。 選擇性地，該密封構件係不在該活動部分及該固定不 動部分間之空間。 選擇性地，該密封構件具有一非平面式輪廓，其被組 構成用以有利於該活動部分之移動。 選擇性地，該密封構件於輪廓中包括至少一背脊及/ 或至少一溝槽。 選擇性地，該密封構件包括一隆起部分，該隆起部分 突出被連接至該活動部分的密封構件之第一端部及被連接 至該固定不動部分之密封構件的第二端部。 選擇性地，該密封構件係成波狀的。 選擇性地，該噴嘴開口被界定在該活動部分中。 選擇性地，該噴嘴開口被界定在該固定不動部分中。 選擇性地，該致動器係一熱彎曲致動器，包括： 第一主動元件，用於連接至驅動電路系統；及 第二被動元件，其與該第一元件機械式地配合， 使得當一電流係通過該第一元件時，該第一元件相對該第 二元件膨脹，導致該致動器之彎曲。 選擇性地，該第一及第二元件係懸臂樑。 選擇性地，該熱彎曲致動器界定該頂板之活動部分的 -9- 201020123 至少一部分。 選擇性地，該聚合體材料係塗覆在該頂板的一相當大 部分上，使得該列印頭的一墨水射出面係疏水性的。 選擇性地，每一頂板形成該列印頭之噴嘴板的至少一 部分，由於該聚合體塗層，每一頂板相對每一噴嘴室之內 側表面具有一疏水性的外側表面。 選擇性地，該噴嘴室包括延伸於該頂板及一基板之間 的側壁，使得該頂板係由該基板隔開。 _ ❿ 選擇性地，該活動部分被組構成於該致動器之致動時 移向該基板。 於另一態樣中，本發明提供一包括複數噴嘴總成之噴 墨列印頭，每一噴嘴總成包括： 一噴嘴室，其包括一頂板，在該頂板中界定一噴 嘴開口，該頂板包括可相對一固定不動部分移動之活動部 分，使得該活動部分相對該固定不動部分之移動造成墨水 經過該噴嘴開口射出； @ 一致動器，用於相對該固定不動部分移動該活動 部分；及 一密封構件，其互連該活動部分及該固定不動部 分， 其中該密封構件具有一被組構成爲有利於該活動部分 之移動的非平面式輪廓。 選擇性地，該列印頭之噴嘴板包括一聚合體塗層。 選擇性地，該聚合體塗層包括該等密封構件。 -10- 201020123 於第二態樣中，本發明提供一噴墨列印頭，其包括： - —固定不動部分； 複數活動部分，用於墨水之射出；及 複數密封構件，每一密封構件連接一個別之活動 部分與該固定不動部分， 其中每一密封構件被組構成爲一跨越其個別之活動部 分及該固定不動部分之間的橋接件。 φ 選擇性地，一噴嘴板包括該複數活動部分及該固定不 動部分。 選擇性地，該噴嘴板包括一撓性聚合體塗層，該塗層 包括該等密封構件。 選擇性地，該聚合體塗層係疏水性的。 選擇性地，該聚合體塗層係由聚二甲基矽氧烷 (PDMS)所組成。 選擇性地’該密封構件係不在該活動部分及該固定不 φ 動部分間之空間。 選擇性地’該密封構件具有一非平面式輪廓，其被組 構成用以有利於該活動部分之活動。 選擇性地，每一密封構件於輪廓中包括至少一背脊及 /或至少一溝槽。 選擇性地’每一密封構件包括一隆起部分，該隆起部 分突出被連接至該活動部分的密封構件之第一端部及被連 接至該固定不動部分之密封構件的第二端部。 選擇性地，每一密封構件係成波狀的。 -11 - 201020123 於另一態樣中，本發明提供一包括複數噴嘴總成之列 印頭，每一噴嘴總成包括： 一噴嘴室，其包括一頂板，在該頂板中界定一噴 嘴開口，該頂板包括可相對該固定不動部分移動的活動部 分之一，使得該活動部分相對該固定不動部分之移動造成 墨水經過該噴嘴開口射出； 一致動器，用於相對該固定不動部分移動該活動201020123 IX. Description of the Invention [Technical Field of the Invention] The present invention relates to the field of printers and, in particular, inkjet print heads. It has been primarily developed to improve print quality and reliability in high resolution printheads. [Prior Art] A number of different print patterns have been invented, and a large number thereof is currently being used to have various methods for marking the print medium with associated mark media. Commonly used printing formats include offset printing, laser printing and copying devices, dot matrix impact printers, thermal paper printers, video recorders, thermal wax printers, dye sublimation printers Machine and the controlled drop type and continuous supply rainer inkjet printer. Each type of printer has its own advantages and problems when considering cost, speed, quality, reliability, structure and ease of operation. In recent years, the field of ink jet printing has become increasingly popular due to its low cost and versatility, where each individual ink element is derived from one or more ink nozzles. Many different techniques for ink jet printing have been invented. For an observation of this area, refer to the output hard copy device, editors R Dubeck and S Sherr, pp. 207-220 (1988) in the name of J Moore, “Non-impact printing: introduction and historical perspective”. There are many different types of inkjet printers. The utilization of the continuous flow of ink in ink jet printing can be traced back to at least 1929. U.S. Patent No. 1,941,001, to the name of Hansell, discloses a simple electrostatic inkjet printing of the continuous stream of 201020123. form. Also disclosed in U. This technology is still used by several manufacturers, including Elmjet and Scitex (see also U.S. Patent No. 3,373,437, to Schwitt et al.). Piezoelectric ink jet printers are also one form of ink jet printing apparatus that is also commonly utilized. A piezoelectric system is disclosed by Kyser et al. in U.S. Patent No. 3,946,398 (1,970), which is incorporated herein by reference to U.S. Patent No. 3,683,221 (1970). It is disclosed in U.S. Patent No. 3,747,120 (1972), which is incorporated herein by reference. The type of shear mode of the piezoelectric sensor element is disclosed in U.S. Patent No. 4,584,590. Recently, thermal ink jet printing has become a very popular ink jet printing type. Such ink jet printing techniques include those disclosed in U.S. Patent No. 4,490,72, the entire disclosure of which is incorporated herein by reference. The foregoing two references disclose an ink jet printing technique that relies on activation of an electrothermal actuator that causes the creation of bubbles in a confined space, such as a nozzle, thereby causing ink to be connected to the confined space The aperture is ejected onto the associated printing medium. The printing device using the electrothermal actuator is made by manufacturers such as Canon and Hewlett-Packard -6-201020123 As can be seen from the front, many different types of printing techniques are available. Ideally, a print technology will have many desirable attributes. These include inexpensive construction and operation, high speed operation, safety and continuous long-term operation. Each technology has its own advantages and disadvantages in areas of cost, speed, quality, reliability, power usage, structural simplicity, durability, and consumables. Φ The Applicant has described an excessive number of ink jet print heads made using Micro Electro Mechanical Systems (MEM S) technology. As described in the Applicant's earlier U.S. Application Serial Nos. 11/685,084; 11/763,443; and 11/763,440, the disclosure of which is incorporated herein by reference, A nozzle plate having a movable portion is included. Each movable portion typically has a nozzle opening defined therein such that actuation of the movable portion causes ink to be ejected from the print head. For example, compared to conventional thermal bubble forming print heads, the advantage of this type of print head is that the energy required to eject an ink droplet is small. The Applicant has previously described how the particular actuator design and supplemental actuation method provides high efficiency droplet ejection from such printheads (see, for example, U.S. Application Serial Nos. 1 1/607,976 and 12/239,81 4). No., the content of which is incorporated herein by reference. However, one problem with • movable nozzles • print heads is that they require a good fluid seal between the active and fixed portions of the print head. The ink should only be ejected through the nozzle and should not leak out of the seal. If the distance between the active portion and the fixed portion is small, 201020123, the surface tension can remain in the ink inside the nozzle chamber. However, the use of surface tension as a fluid-tight ink is problematic and generally does not provide a reliable seal, especially if the ink inside the nozzle chamber experiences a pressure surge. A method of manufacturing a mechanical seal for the movable portion of the nozzle plate has been described in the applicant's earlier application, No. 1 1/685,084, 1 1/763,443, and 1 1/763,440. Typically, a flexible layer of polydimethyl siloxane (PDMS) is applied over the nozzle plate as a sealing film between the movable portion of the print head and the stationary portion. Furthermore, the PDMS layer provides a hydrophobic ink exit surface which is highly desirable from the standpoint of print head jet technology and final print quality. It would be desirable to provide an improved mechanical seal for an ink jet printhead having a movable nozzle. It would be particularly desirable to provide an effective mechanical seal with minimal impact on the overall efficiency of the printhead. SUMMARY OF THE INVENTION In a first aspect, the present invention provides a nozzle assembly for an ink jet print head, the nozzle assembly comprising: a nozzle chamber including a top plate defining a nozzle opening therein The top plate includes a movable portion movable relative to a fixed portion such that movement of the movable portion relative to the fixed portion causes ink to be ejected through the nozzle opening; an actuator for moving the movable portion relative to the fixed portion; -8 - 201020123 A sealing member that is grouped into a bridge member that spans between the movable portion and the fixed portion. Optionally, the sealing member is comprised of a polymeric material. Optionally, the polymeric material consists of polydimethyl siloxane (PDMS). Optionally, the sealing member is not in the space between the movable portion and the fixed portion. Optionally, the sealing member has a non-planar profile that is configured to facilitate movement of the movable portion. Optionally, the sealing member includes at least one ridge and/or at least one groove in the profile. Optionally, the sealing member includes a raised portion that projects a first end of the sealing member that is coupled to the movable portion and a second end that is coupled to the sealing member of the fixed portion. Optionally, the sealing member is corrugated. Optionally, the nozzle opening is defined in the active portion. Optionally, the nozzle opening is defined in the fixed portion. Optionally, the actuator is a thermal bending actuator comprising: a first active component for connecting to the drive circuitry; and a second passive component mechanically mating with the first component such that When a current is passed through the first component, the first component expands relative to the second component, causing bending of the actuator. Optionally, the first and second components are cantilever beams. Optionally, the thermal bending actuator defines at least a portion of the active portion of the top plate -9-201020123. Optionally, the polymeric material is applied to a substantial portion of the top plate such that an ink exit surface of the printhead is hydrophobic. Optionally, each top plate forms at least a portion of the nozzle plate of the printhead, each of which has a hydrophobic outer surface relative to the inner side surface of each of the nozzle chambers due to the polymeric coating. Optionally, the nozzle chamber includes a sidewall extending between the top plate and a substrate such that the top plate is separated by the substrate. _ 选择性 Optionally, the active portion is configured to move toward the substrate when the actuator is actuated. In another aspect, the present invention provides an inkjet printhead including a plurality of nozzle assemblies, each nozzle assembly comprising: a nozzle chamber including a top plate defining a nozzle opening in the top plate, the top plate The movable portion is movable relative to a fixed portion, such that movement of the movable portion relative to the fixed portion causes ink to be ejected through the nozzle opening; @an actuator for moving the movable portion relative to the fixed portion; and A sealing member interconnecting the movable portion and the fixed portion, wherein the sealing member has a non-planar profile that is configured to facilitate movement of the movable portion. Optionally, the nozzle plate of the printhead includes a polymeric coating. Optionally, the polymeric coating comprises the sealing members. -10- 201020123 In a second aspect, the present invention provides an ink jet print head comprising: - a fixed portion; a plurality of movable portions for ink ejection; and a plurality of sealing members, each sealing member connected And a further movable portion and the fixed portion, wherein each of the sealing members is formed as a bridge between its individual movable portion and the fixed portion. φ Optionally, a nozzle plate includes the plurality of movable portions and the fixed fixed portion. Optionally, the nozzle plate includes a flexible polymeric coating comprising the sealing members. Optionally, the polymeric coating is hydrophobic. Optionally, the polymeric coating consists of polydimethyl methoxy alkane (PDMS). Optionally, the sealing member is not in the space between the movable portion and the fixed non-φ movable portion. Optionally, the sealing member has a non-planar profile that is configured to facilitate movement of the active portion. Optionally, each sealing member includes at least one ridge and/or at least one groove in the contour. Optionally, each of the sealing members includes a raised portion that projects a first end of the sealing member that is coupled to the movable portion and a second end that is coupled to the sealing member of the fixed portion. Optionally, each sealing member is corrugated. -11 - 201020123 In another aspect, the present invention provides a printhead including a plurality of nozzle assemblies, each nozzle assembly comprising: a nozzle chamber including a top plate defining a nozzle opening therein The top plate includes one of movable portions movable relative to the fixed portion such that movement of the movable portion relative to the fixed portion causes ink to be ejected through the nozzle opening; an actuator for moving the activity relative to the fixed portion
部分；及 該等密封構件之一橋接於該活動部分及該固定不 動部分之間。 選擇性地，該噴嘴開口被界定在該活動部分中。 選擇性地，該噴嘴開口被界定在該固定不動部分中。 選擇性地，該致動器係一熱彎曲致動器，包括：a portion; and one of the sealing members is bridged between the movable portion and the fixed portion. Optionally, the nozzle opening is defined in the active portion. Optionally, the nozzle opening is defined in the fixed portion. Optionally, the actuator is a thermal bending actuator comprising:
第一主動元件，用於連接至驅動電路系統；及 第二被動元件，其與該第一元件機械式地配合， 使得當一電流係通過該第一元件時，該第一元件相對該第 選擇性地，該第一及第二元件係懸臂樑。 選擇性地，該熱彎曲致動器界定該頂板之活動部分的 至少一部分。 選擇性地，該噴嘴室包括延伸於該頂板及一基板之間 的側壁，使得該頂板係由該基板隔開。 選擇性地，該活動部分被組構成於該致動器之致動時 移向該基板。 -12- 201020123 選擇性地’該頂板及該等側壁係由可藉著CVD沈積 之陶瓷材料所組成，該陶瓷材料係選自包括：氮化砂、氧 化矽及氮氧化矽之群組。 於另一態樣中’本發明提供一包括根據申請專利範圍 第1項之列印頭的噴墨印表機。 於第二態樣中’本發明提供具有一橋接在活動部分及 固定不動部分間之密封構件的噴墨噴嘴總成之製造方法， φ 該方法包括以下步驟： (a) 提供一局部製成之列印頭，其包括一以頂板 密封之噴嘴室； (b) 蝕刻一穿過該頂板之通孔，以界定在該通孔 的第一側面上之活動部分及在該通孔的第二側面上之固定 不動部分； (c) 以犧牲材料之插塞插入該通孔； (d) 至少在該插塞上方沈積一撓性材料層；及 φ (e)移去該插塞，以提供使該密封構件橋接於該 活動部分及該固定不動部分之間的噴墨噴嘴總成，其中該 密封構件係由該撓性材料所組成。 選擇性地，該撓性材料係一聚合體材料。 選擇性地，該撓性材料係由聚二甲基矽氧烷（PDMS) 所組成。 選擇性地，該插塞充塡該通孔，使得該密封構件係不 在該通孔。 選擇性地，該插塞具有一延伸出該通孔之頭部，該頭 -13- 201020123 部呈現一用於該撓性材料之沈積的台架表面。 選擇性地，該密封構件具有一非平面式輪廓，其被組 構成用以有利於該活動部分之活動。 選擇性地，該密封構件於輪廓中包括至少一背脊及/ 或至少一溝槽。a first active component for connecting to the driving circuitry; and a second passive component mechanically mated with the first component such that when a current is passed through the first component, the first component is opposite the first component Optionally, the first and second components are cantilever beams. Optionally, the thermal bending actuator defines at least a portion of the active portion of the top plate. Optionally, the nozzle chamber includes a sidewall extending between the top plate and a substrate such that the top plate is separated by the substrate. Optionally, the active portion is configured to move toward the substrate when the actuator is actuated. -12- 201020123 Optionally, the top plate and the side walls are comprised of a ceramic material that can be deposited by CVD, the ceramic material being selected from the group consisting of: sand nitride, cerium oxide, and lanthanum oxynitride. In another aspect, the present invention provides an ink jet printer comprising a print head according to claim 1 of the scope of the patent application. In a second aspect, the invention provides a method of fabricating an ink jet nozzle assembly having a sealing member bridged between a movable portion and a stationary portion, φ the method comprising the steps of: (a) providing a partially formed a printing head comprising a nozzle chamber sealed by a top plate; (b) etching a through hole passing through the top plate to define a movable portion on the first side of the through hole and a second side of the through hole a fixed portion; (c) inserting the through hole with a plug of the sacrificial material; (d) depositing a layer of flexible material at least over the plug; and φ (e) removing the plug to provide The sealing member bridges the inkjet nozzle assembly between the movable portion and the stationary portion, wherein the sealing member is comprised of the flexible material. Optionally, the flexible material is a polymeric material. Optionally, the flexible material consists of polydimethyl siloxane (PDMS). Optionally, the plug fills the through hole such that the sealing member is not in the through hole. Optionally, the plug has a head extending out of the through hole, and the head -13 - 201020123 presents a gantry surface for deposition of the flexible material. Optionally, the sealing member has a non-planar profile that is configured to facilitate movement of the active portion. Optionally, the sealing member includes at least one ridge and/or at least one groove in the profile.
選擇性地，該密封構件包括一隆起部分，該隆起部分 突出被連接至該活動部分的密封構件之第一端部及被連接 至該固定不動部分之密封構件的第二端部。 選擇性地，該密封構件係成波狀的。 於另一態樣中，本發明提供一方法，其另包括該步驟 在移除該犧牲材料之前蝕刻一穿過該頂板之噴嘴 開口。 選擇性地，該噴嘴開口被蝕刻穿過該活動部分。 選擇性地，該活動部分包括一熱彎曲致動器。 選擇性地，該熱彎曲致動器包括： 第一主動元件，用於連接至驅動電路系統；及 第二被動元件，其與該第一元件機械式地配合， 使得當一電流係通過該第一元件時，該第一元件相對該第 二元件膨脹，導致該致動器之彎曲。 選擇性地，該撓性材料係一疏水性的材料，且其中該 携性材料之沈積係在該頂板的一相當大部分上方，使得該 頂板係相對疏水性的。 選擇性地，該噴嘴室包括延伸於該頂板及一基板間之 -14- 201020123 側壁，使得該頂板係由該基板隔開。 選擇性地，該活動部分被組構成於致動器之致動時移 向該基板。 選擇性地，該撓性層於移除該插塞之前被覆蓋以犧牲 保護金屬層。 選擇性地，該犧牲保護金屬層係在移除該插塞之後被 移去。 選擇性地，該插塞係藉由將該噴嘴總成暴露至氧化電 漿而移除。 於另一態樣中，本發明提供一使密封構件橋接於一活 動部分及一固定不動部分之間的噴墨噴嘴總成，其中該密 封構件係由沈積在該噴嘴總成之頂板上方的撓性材料所組 成。 【實施方式】 • 於活動部分及固定不動部分之間具有聚合物充塡空間的噴 嘴總成 圖1至 16顯示用於我們的稍早美國申請案第 11/7 63,44 0號中所敘述之噴墨噴嘴總成100的MEMS製造 步驟之順序，該申請案係以引用的方式倂入本文中。圖 15及16所示之已完成的噴墨噴嘴總成1〇〇利用熱彎曲致 動，藉此一頂板之活動部分彎曲朝向一基板，導致墨水射 出。 用於MEMS製造之起點係一標準之CMOS晶圓，並 -15- 201020123 具有形成在一矽晶圓的上部中之CM0S驅動電路系統。在 該MEMS製造製程之末端，此晶圓被切成個別之列印頭 積體電路（ICs)，使每一 1C包括致動器電路系統及複數噴 嘴總成。 如圖1及2所示，基板1具有一形成於其上部中之電 極2。該電極2係一對鄰接電極（陽極與接地）之一，用於 供給電力至該噴墨噴嘴1〇〇之致動器。該等電極承接來自 基板1的上層中之CMOS驅動電路系統（未示出）的電力。 圖1及2所示之另一電極3係用於供給電力至一鄰接 之噴墨噴嘴。大致上，該等圖面顯示用於噴嘴總成之 MEMS製造步驟，該噴嘴總成係噴嘴總成陣列之一。以下 之敘述集中在用於這些噴嘴總成之一的製造步驟。然而， 當然應了解對於形成在該晶圓上之所有噴嘴總成，對應之 步驟被同時地施行。在此一鄰接之噴嘴總成被局部地顯示 在該等圖面中，這用於本目的可被暫時地忽視。據此，該 電極3及該鄰接之噴嘴總成之所有特色將不在此被詳細地 敘述。實際上，爲了清楚故，一些MEMS製造步驟將不 被顯示在鄰接之噴嘴總成上。 於圖1及2所示步驟之順序中，二氧化矽之8微米層 係最初沈積於該基板1上。二氧化矽之深度界定一用於該 噴墨噴嘴的噴嘴室5之深度。在Si02層的沈積之後，其 被蝕刻至界定壁面4，該等壁面將變成該噴嘴室5之側壁 ’其最清楚地顯示在圖2中。 如圖3及4所示，該噴嘴室5係接著以用作隨後沈積 -16- 201020123 步驟之犧牲台架的光阻劑或聚醯亞胺6充塡。該聚醯亞胺 6係使用標準之技術旋轉製成至該晶圓上、UV硬化及/ 或烤硬、且接著遭受化學機械平面化（CMP)，並停止在該 Si02壁面4的頂部表面。 於圖5及6中，形成該噴嘴室5之頂板構件7以及往 下延伸直至該等電極2之高傳導性連接器支柱8。最初， 1.7微米之3丨02層係沈積於該聚醢亞胺6及壁面4上。此 Si〇2層界定該噴嘴室5的一頂板7。其次，一對通孔係使 用一標準之各向異性的DRIE往下直至該等電極2形成在 該壁面4中。此蝕刻經過個別之通孔暴露該對電極2。其 次，該等通孔使用無電鍍被充塡以高傳導性之金屬、諸如 銅。所沈積之銅支柱8係遭受CMP，停止在該Si02頂板 構件7上，以提供一平面式結構。其能被看出於該無電銅 電鍍期間所形成之銅連接器支柱8與個別之電極2相合， 以上至該頂板構件7提供一線性傳導路徑。 於圖7及8中，金屬墊片9係藉由最初沈積0.3微米 之鋁層至該頂板構件7及連接器支柱8所形成。任何高傳 導性金屬（例如鋁、鈦等）可被使用，且應被沈積具有大約 0.5微米或更少之厚度，以便不會太猛烈地撞擊在該噴嘴 總成之整個平面性上。 該等金屬墊片9係於該熱彈性主動樑構件之預定'彎 曲區域'中定位在該等連接器支柱8上方及在該頂板構件7 上。 於圖9及10中，熱彈性主動樑構件1〇係形成在該 -17- 201020123Optionally, the sealing member includes a raised portion that projects a first end of the sealing member that is coupled to the movable portion and a second end that is coupled to the sealing member of the fixed portion. Optionally, the sealing member is corrugated. In another aspect, the invention provides a method that additionally includes the step of etching a nozzle opening through the top plate prior to removing the sacrificial material. Optionally, the nozzle opening is etched through the active portion. Optionally, the active portion includes a thermal bending actuator. Optionally, the thermal bending actuator comprises: a first active component for connecting to the driving circuitry; and a second passive component mechanically mating with the first component such that when a current system passes the first When a component is in use, the first component expands relative to the second component, resulting in bending of the actuator. Optionally, the flexible material is a hydrophobic material, and wherein the deposition of the carrier material is over a substantial portion of the top plate such that the top plate is relatively hydrophobic. Optionally, the nozzle chamber includes a sidewall extending from the top plate and a substrate between -14 and 201020123 such that the top plate is separated by the substrate. Optionally, the active portion is configured to move toward the substrate upon actuation of the actuator. Optionally, the flexible layer is covered to sacrifice the protective metal layer prior to removing the plug. Optionally, the sacrificial protective metal layer is removed after removal of the plug. Optionally, the plug is removed by exposing the nozzle assembly to oxidizing plasma. In another aspect, the present invention provides an inkjet nozzle assembly for bridging a sealing member between a movable portion and a stationary portion, wherein the sealing member is sheathed by a top plate deposited on the top of the nozzle assembly Made up of materials. [Embodiment] The nozzle assembly having a polymer filling space between the movable portion and the stationary portion is shown in Figs. 1 to 16 for use in our earlier US application No. 11/7 63,44 0 The sequence of MEMS fabrication steps for the inkjet nozzle assembly 100 is incorporated herein by reference. The completed ink jet nozzle assembly shown in Figures 15 and 16 is actuated by thermal bending whereby the movable portion of a top plate is bent toward a substrate, causing the ink to be ejected. The starting point for MEMS manufacturing is a standard CMOS wafer, and -15-201020123 has a CMOS drive circuit system formed in the upper portion of a wafer. At the end of the MEMS fabrication process, the wafer is diced into individual print head integrated circuits (ICs) such that each 1C includes an actuator circuitry and a plurality of nozzle assemblies. As shown in Figures 1 and 2, the substrate 1 has an electrode 2 formed in its upper portion. The electrode 2 is one of a pair of adjacent electrodes (anode and ground) for supplying electric power to the actuator of the ink jet nozzle 1 . The electrodes receive power from CMOS drive circuitry (not shown) in the upper layer of substrate 1. The other electrode 3 shown in Figures 1 and 2 is for supplying electric power to an adjacent ink jet nozzle. In general, the drawings show the MEMS fabrication steps for the nozzle assembly, which is one of the arrays of nozzle assemblies. The following description focuses on the manufacturing steps for one of these nozzle assemblies. However, it should of course be understood that for all nozzle assemblies formed on the wafer, the corresponding steps are performed simultaneously. Here, an adjacent nozzle assembly is partially displayed in the drawings, which can be temporarily ignored for this purpose. Accordingly, all features of the electrode 3 and the adjacent nozzle assembly will not be described in detail herein. In fact, some MEMS fabrication steps will not be shown on adjacent nozzle assemblies for clarity. In the sequence of steps shown in Figures 1 and 2, an 8 micron layer of cerium oxide is initially deposited on the substrate 1. The depth of the cerium oxide defines a depth for the nozzle chamber 5 of the ink jet nozzle. After deposition of the SiO 2 layer, it is etched to define the wall surface 4 which will become the sidewall of the nozzle chamber 5 which is most clearly shown in Figure 2. As shown in Figures 3 and 4, the nozzle chamber 5 is then filled with a photoresist or polyimine 6 which serves as a sacrificial gantry for the subsequent deposition of the -16-201020123 step. The polyimine 6 is spin-formed onto the wafer using standard techniques, UV hardened and/or baked, and then subjected to chemical mechanical planarization (CMP) and stopped at the top surface of the SiO 2 wall 4. In Figs. 5 and 6, the top plate member 7 of the nozzle chamber 5 and the highly conductive connector post 8 extending downwardly to the electrodes 2 are formed. Initially, a 1.7 micron layer of 3 丨 02 layer was deposited on the polyimine 6 and the wall 4 . This Si〇2 layer defines a top plate 7 of the nozzle chamber 5. Next, a pair of through holes are lowered using a standard anisotropic DRIE until the electrodes 2 are formed in the wall 4. This etching exposes the pair of electrodes 2 through individual vias. Second, the vias are filled with a highly conductive metal such as copper using electroless plating. The deposited copper posts 8 are subjected to CMP and are stopped on the SiO 2 top member 7 to provide a planar structure. It can be seen that the copper connector posts 8 formed during the electroless copper plating are associated with the individual electrodes 2, and the top plate member 7 provides a linear conduction path. In Figs. 7 and 8, the metal spacer 9 is formed by initially depositing a 0.3 micron aluminum layer to the top plate member 7 and the connector post 8. Any highly conductive metal (e.g., aluminum, titanium, etc.) can be used and should be deposited to a thickness of about 0.5 microns or less so as not to impinge too violently on the overall planarity of the nozzle assembly. The metal spacers 9 are positioned above the connector posts 8 and on the top plate member 7 in a predetermined 'bending region' of the thermoelastic active beam member. In Figures 9 and 10, a thermoelastic active beam member 1 is formed in the -17-201020123
Si〇2頂板7上方。由於被熔合至該主動樑構件i〇，該 Si〇2頂板構件7的一部分用作—機械式熱彎曲致動器的下 被動樑構件16 ’其被該主動樑10及該被動樑16所界定 。該熱彈性主動樑構件10可爲由任何合適之熱彈性材料 、諸如氮化欽、氮化鈦鋁及鋁合金所組成。如於該申請人 在2002年12月4日提出之稍早美國申請案第11/607,976 號中所說明’其內容係以引用的方式倂入本文中，釩-鋁 合金係一較佳材料，因爲它們結合高熱膨脹係數、低密度 及高楊氏模數之有利性質。 爲形成該主動樑構件10，1.5微米之主動樑材料層係 最初藉由標準PECVD所沈積。該樑材料接著使用一標準 之金屬蝕刻法被飩刻，以界定該主動樑構件10。在完成 該金屬蝕刻之後及如圖9及10所示，該主動樑構件10包 括一局部之噴嘴開口 1 1及一樑元件1 2，該樑元件係在每 一端部經由該等連接器支柱8電連接至陽極及接地電極2 。該平面式樑元件12由第一（陽極）連接器支柱之頂部延 伸，且彎曲約180度，以返回至第二（接地）連接器支柱之 頂部。 仍參考圖9及10，該等金屬墊片9被定位至有利於 潛在較高電阻的區域中之電流流動。一金屬墊片9被定位 在該樑元件12的一彎曲區域，且被夾在該主動樑構件1〇 及該被動樑構件16之間。其他金屬墊片9被定位在該等 連接器支柱8之頂部及該樑元件12的端部之間。 參考圖1 1及12，該Si02頂板構件7接著被蝕刻，以 -18- 201020123 完全界定該頂板的一噴嘴開口 13及—活動部分14。該活 動部分14包括一熱彎曲致動器15’其本身係由該主動樑 構件10及該在下面的被動樑構件16所組成。該噴嘴開口 13被界定於該頂板之活動部分14中’以致該噴嘴開口於 致動期間隨著該致動器移動。諸組構係亦可能的’藉此該 噴嘴開口 13係相對於該活動部分14固定不動的，如在申 請人之美國申請案第1 1 /607,976號中所敘述’其係以引 φ 用的方式倂入本文中。 一環繞著該頂板的活動部分14之周邊空間或間隙17 由該頂板之固定不動部分18分開該活動部分。當致動該 致動器15時，此間隙17允許該活動部分14彎曲進入該 噴嘴室5及朝向該基板1。 參考圖13及14，可光佈圖的疏水性聚合物層19接 著被沈積在該整個噴嘴總成上方，且被光佈圖至重新界定 該噴嘴開口 13。 • 使用可光佈圖的聚合物以塗覆噴嘴總成之陣列係廣泛 地敘述於吾人在2007年3月12日提出之稍早美國申請案 第1 1 /685,084號、及在2007年4月27日提出之第 1 1/740,925號，其內容係以引用的方式倂入本文中。典型 地，該疏水性聚合物係聚二甲基矽氧烷（PDMS)或聚全氟 丙烯（PFPE)。此等聚合物係特別有利的，因爲它們係可光 佈圖的，具有高疏水性、及低楊氏模數。 如於該前述之美國申請案中所說明，倂入該疏水性聚 合物的MEMS製造步驟之正確順序係相當有彈性的。譬 201020123 如，其完美可施行的是在沈積該疏水性聚合物之後蝕刻該 噴嘴開口 13’並使用該聚合物當作一用於該噴嘴餓刻之 罩幕。將了解MEM S製造步驟的正確順序上之變化係充 分地在該熟練之人士的範圍內’且再者被包括在本發明之 範圍內。 該疏水性聚合物層19施行數個功能。首先’其充塡 該間隙17，以於該頂板7的活動部分14及固定不動部分 18之間提供一機械式密封。倘若該聚合物具有一充分低 之楊氏模數，該致動器仍然能夠彎曲朝向該基板1’而防 止墨水於致動期間經過該間隙1 7溢出。其次，該聚合物 具有一高疏水性，其使氾濫離開該等相對親水性噴嘴室及 至該列印頭的墨水射出面21之墨水的傾向減至最小。第 三，該聚合物用作一保護層，其有利於列印頭維護。 最後及如圖15及16所示，墨水供給通道20係由該 基板1之背部蝕刻穿過至該噴嘴室5。雖然該墨水供給通 道20被顯示爲與圖15及16中之噴嘴開口 13對齊，其當 然可被定位成由該噴嘴開口偏置。 在蝕刻該墨水供給通道之後，充塡該噴嘴室5之聚醯 亞胺6係使用例如02電漿以提供該噴嘴總成100而藉由 灰化（前側灰化或背部灰化的其中之一）被移去。 雖然未在上面敘述，金屬薄膜（例如鈦或鋁）可被用來 於最後階段之MEMS處理期間保護該聚合物層19，如吾 人之稍早的美國申請案第1 1 /740,925及1 1 /946,840號中 所敘述，其內容係以引用的方式倂入本文中。典型地，該 -20- 201020123 保護金屬薄膜係於蝕刻該噴嘴開口 13之前沈積在該聚合 物層19上。在已完成所有蝕刻及氧化光阻劑移除步驟（“ 灰化步驟”）之後，該保護金屬薄膜可使用簡單之HF或 H2〇2沖洗被移去。 在活動部分及固定不動部分之間具有聚合物橋接空間的噴 嘴總成 於上述該噴嘴總成100中，該聚合物層19充塡該頂 板7的活動部分14及固定不動部分18間之間隙。雖然這 提供一良好之機械式密封及可被輕易地製成，該密封之組 構不可避免地撞擊在該噴嘴總成之整個性能及效率上。 翻至圖17至22，已槪要地顯示有製造步驟之另一選 擇的順序，其導致一改良的密封構件橋接於該活動部分 14及固定不動部分18之間。爲了簡單性，圖17至22中 之槪要圖示不顯示該致動器之詳細部件。然而，將了解圖 17係圖9及10所示該局部形成'噴嘴總成之槪要代表圖， 其係用於製造步驟之此另一選擇的順序之起點。爲了清楚 故，類似參考數字將被使用，以意指該噴嘴總成中之對應 部件。 然後參考至圖17，顯示有一具有充塡以聚醯亞胺6 之噴嘴室5的局部形成之噴嘴總成。包括一熱彎曲致動器 (在圖17中未示出）之頂板7在該噴嘴室5上方形成一蓋 子。 於圖18中，一通孔被鈾刻進入該頂板7。該通孔界 -21 - 201020123 定該頂板7的活動部分14及固定不動部分18間之間隙 17。 其次參考圖1 9，該間隙1 7被以諸如光阻劑的犧牲材 料之插塞30充塡。該插塞30具有犧牲台架之作用，用於 在隨後之步驟中沈積一聚合體密封構件。特別地是，該插 塞30之上表面界定該密封構件之輪廓。該插塞30之組構 及其上表面之輪廓可被傳統之光微影技術所控制。譬如， 可於該光阻劑之曝光期間藉由調整一聚焦參數形成該插塞 3 〇之傾斜側壁。 在形成該插塞30之後，該局部形成之噴嘴總成係接 著被塗覆以一撓性聚合體材料層19。典型地，該聚合體 材料係聚二甲基矽氧烷（PDMS)。如在圖20中所示，該 PDMS層19配合該噴嘴總成之上表面的輪廓。 一保護之鋁薄膜31隨後被沈積在該PDMS層19上方 。該鋁薄膜31保護該PDMS層19，使其不遭受一用於移 除聚醯亞胺6之氧化電漿（圖22)。 現在參考圖21，該噴嘴開口 13係接著被蝕刻穿過該 鋁薄膜31、該PDMS層19、及該頂板7所界定。在不同 階段，此蝕刻可需要不同之鈾刻化學組成，以便蝕刻穿過 所有二層。 最後及參考圖22，該噴嘴總成係遭受一移去該聚醯 亞胺6及光阻劑插塞3 0之氧化電漿（例如〇2電漿）。在氧 化移除該聚醯亞胺6及插塞30之後，該保護之鋁層31係 藉由在HF或H202中之洗滌所移去。 -22- 201020123 圖22所示之已完成的噴嘴總成200具有一橋接越過 該頂板7的活動部分14及固定不動部分18間之間隙17 的密封構件32。顯著地是，該密封構件32不會充塡該間 隙17，且係實際上，完全地不在於該活動部分14及該固 定不動部分1 8間之空間。 該密封構件32具有一橋接件之輪廓，在此一端部係 連接至該活動部分14，且該另一端部係連接至該固定不 動部分18。再者，該橋接件大體上採取單一拱橋之形式 ，具有一突出於該橋接件之每一端.部的背脊或隆起部分 33。當然，視該插塞30之上表面的輪廓而定，該密封構 件可另一選擇地採取一跨接於該活動部分14及固定不動 部分18間之簡單樑橋接件的形式。 該密封構件32具有勝過圖15及16所示具體實施例 之若干優點，在此該間隙17被完全地充塡以該聚合體材 料19。首先，藉由減少該活動部分14及該固定不動部分 18間之聚合物的整個體積，對該活動部分14之往下運動 朝向該基板1有遠較小之阻抗。此外，該密封構件之輪廓 係特別設計成適於有利於該活動部分1 4之往下運動。既 然該密封構件3 2採取一撓性橋接件之形式，具有一比該 活動部分14及固定不動部分18間之距離較長的長度，該 活動部分14於致動期間之任何往下運動可被該橋接件結 構以該聚合物材料之最小撓曲或延伸而輕易地調節。因此 ，該密封構件32對該活動部分14之移動提供最小阻抗， 而仍然提供一優異之密封。藉由使對該活動部分14之移 -23- 201020123 動的阻抗減至最小，該噴嘴總成200、及包括此等噴嘴總 成的列印頭之整個效率被改善。 當然，該密封構件32之其他組構係在本發明之範圍 內。譬如，如圖23所示，該密封構件32可爲一具有複數 背脊41及溝槽42之成波狀的結構40。應了解該成波狀 的結構40可輕易地調節該活動部分14之移動。 此領域中之普通工作者應了解可對本發明作成極多之 變化及/或修改，如在該等特定具體實施例中所示，而未 由如槪括地敘述的本發明之精神與範圍脫離。因此，該等 正在考慮中之具體實施例在所有方面將被考慮爲說明性及 非限制性的。 【圖式簡單說明】 現在將僅只參考所附圖面經由範例敘述本發明之選擇 性具體實施例，其中： 圖1係在諸步驟的第一順序之後局部製成的噴墨噴嘴 總成之側面剖視圖，其中噴嘴室側壁被形成； 圖2係圖4所示該局部製成之噴墨噴嘴總成的一透視 Γοΐ ♦ 圖， 圖3係在諸步驟的第二順序之後局部製成的噴墨噴嘴 總成之側面剖視圖，其中該噴嘴室係以聚醯亞胺充塡； 圖4係圖3所示該局部製成之噴墨噴嘴總成的一透視 圖； 圖5係在諸步驟的第三順序之後局部製成的噴墨噴嘴 -24- 201020123 總成之側面剖視圖，其中該等連接器支柱係形成直至一室 頂板； 圖6係圖5所示該局部製成之噴墨噴嘴總成的一透視 ΓαΤ · 圖， 圖7係在諸步驟的第四順序之後局部製成的噴墨噴嘴 總成之側面剖視圖，其中傳導性金屬板被形成； 圖8係圖7所示該局部製成之噴墨噴嘴總成的一透視 圖 圖9係在諸步驟的第五順序之後局部製成的噴墨噴嘴 總成之側面剖視圖，其中一熱彎曲致動器之主動樑構件被 形成； 圖10係圖9所示該局部製成之噴墨噴嘴總成的一透 視圖； 圖11係在諸步驟的第六順序之後局部製成的噴墨噴 嘴總成之側面剖視圖，其中一包括該熱彎曲致動器之活動 Φ 頂板部分被形成； 圖12係圖11所示該局部製成之噴墨噴嘴總成的一透 視圖； 圖13係在諸步驟的第七順序之後局部製成的噴墨噴 嘴總成之側面剖視圖’其中疏水性聚合物層被沈積及光佈 t 〇-| · 圖， 圖14係圖13所示該局部製成之噴墨噴嘴總成的一透 視圖； 圖1 5係一完全形成之噴墨噴嘴總成的側面剖視圖； -25- 201020123 圖1 6係圖1 5所示該噴墨噴嘴總成之剖面的透視圖； 圖17係圖9及10所示該局部製成之噴墨噴嘴總成的 一槪要側面剖視圖； 圖18係在蝕刻一通孔以界定一室頂板之活動及固定 不動部分之後，圖17所示該局部製成之噴墨噴嘴總成的 一槪要側面剖視圖； 圖1 9係在以光阻劑的插塞充塡該通孔之後，圖1 8所 示該局部製成之噴墨噴嘴的一槪要側面剖視圖； ❹ 圖20係在沈積一聚合物層及一保護金屬層之後，圖 19所示該局部製成之噴墨噴嘴的一槪要側面剖視圖； 圖21係在蝕刻一噴嘴開口之後，圖20所示該局部製 成之噴墨噴嘴的一槪要側面剖視圖； 圖22係一根據本發明之噴墨噴嘴總成的槪要側面剖 視圖；及 圖2 3係另一選擇密封構件之槪要側面剖視圖。 φ 【主要元件符號說明】 1 :基板 2 :電極 3 :電極 4 :壁面 5 :噴嘴室 6 :聚醯亞胺 7 :頂板構件 26- 201020123 8 :連接器支柱 9 :金屬墊片 1 〇 :主動樑構件 1 1 :噴嘴開口 1 2 :樑元件 1 3 :噴嘴開口 1 4 :活動部分 @ 1 5 :熱彎曲致動器 1 6 :被動樑構件 1 7 :間隙 1 8 :固定不動部分 19 :聚合物 20 :墨水供給通道 2 1 :墨水射出面 30 :插塞 φ 31 :薄膜 3 2 :密封構件 3 3 :隆起部分 40:成波狀的結構 4 1 :背脊 42 :溝槽 100 :噴墨噴嘴總成 2 0 0 :噴嘴總成Above the Si〇2 top plate 7. Due to being fused to the active beam member i, a portion of the Si〇2 top plate member 7 acts as a lower passive beam member 16' of the mechanical thermal bending actuator, which is defined by the active beam 10 and the passive beam 16. . The thermoelastic active beam member 10 can be comprised of any suitable thermoelastic material, such as nitride, titanium aluminum nitride, and aluminum alloy. As described in the applicant's earlier U.S. Application Serial No. 11/607,976, the disclosure of which is incorporated herein by reference in its entirety, Because they combine the advantageous properties of high thermal expansion coefficient, low density and high Young's modulus. To form the active beam member 10, a 1.5 micron active beam material layer was initially deposited by standard PECVD. The beam material is then etched using a standard metal etch to define the active beam member 10. After completion of the metal etching and as shown in FIGS. 9 and 10, the active beam member 10 includes a partial nozzle opening 11 and a beam member 12, the beam member being attached to the connector post 8 at each end. Electrically connected to the anode and ground electrode 2 . The planar beam member 12 extends from the top of the first (anode) connector post and is bent about 180 degrees to return to the top of the second (ground) connector post. Still referring to Figures 9 and 10, the metal spacers 9 are positioned to facilitate current flow in regions of potentially higher resistance. A metal spacer 9 is positioned in a curved region of the beam member 12 and sandwiched between the active beam member 1A and the passive beam member 16. Other metal spacers 9 are positioned between the top of the connector posts 8 and the ends of the beam members 12. Referring to Figures 11 and 12, the SiO 2 top member 7 is then etched to completely define a nozzle opening 13 and a movable portion 14 of the top plate at -18-201020123. The movable portion 14 includes a thermal bending actuator 15' which is itself comprised of the active beam member 10 and the underlying passive beam member 16. The nozzle opening 13 is defined in the movable portion 14 of the top plate such that the nozzle opening moves with the actuator during actuation. It is also possible that the configuration of the nozzle opening 13 is fixed relative to the movable portion 14 as described in the applicant's U.S. Application Serial No. 1 1/607,976, which is incorporated herein by reference. The way to break into this article. A peripheral space or gap 17 surrounding the movable portion 14 of the top plate is separated from the movable portion by the fixed portion 18 of the top plate. This gap 17 allows the movable portion 14 to bend into the nozzle chamber 5 and toward the substrate 1 when the actuator 15 is actuated. Referring to Figures 13 and 14, a opaque hydrophobic polymer layer 19 is deposited over the entire nozzle assembly and is optically patterned to redefine the nozzle opening 13. • The use of illuminating polymers to coat the array of nozzle assemblies is widely described in our earlier US application No. 1 1 /685,084, and in April 2007, on March 12, 2007. No. 1/740,925, filed on the 27th, the content of which is incorporated herein by reference. Typically, the hydrophobic polymer is polydimethyl siloxane (PDMS) or polyperfluoro propylene (PFPE). These polymers are particularly advantageous because they are optically etchable, have high hydrophobicity, and have low Young's modulus. As explained in the aforementioned U.S. application, the correct sequence of MEMS fabrication steps to break into the hydrophobic polymer is quite elastic.譬 201020123 For example, it is perfectly achievable to etch the nozzle opening 13' after depositing the hydrophobic polymer and to use the polymer as a mask for the nozzle to be hungry. It will be appreciated that variations in the correct order of the MEM S manufacturing steps are well within the scope of the skilled person's and are intended to be included within the scope of the invention. The hydrophobic polymer layer 19 performs several functions. First, the gap 17 is filled to provide a mechanical seal between the movable portion 14 of the top plate 7 and the fixed portion 18. If the polymer has a sufficiently low Young's modulus, the actuator can still be bent toward the substrate 1' to prevent ink from escaping through the gap 17 during actuation. Second, the polymer has a high hydrophobicity which minimizes the tendency to flood the ink from the relatively hydrophilic nozzle chamber and to the ink exit surface 21 of the printhead. Third, the polymer acts as a protective layer that facilitates printhead maintenance. Finally, and as shown in Figs. 15 and 16, the ink supply passage 20 is etched through the back of the substrate 1 to the nozzle chamber 5. Although the ink supply channel 20 is shown aligned with the nozzle opening 13 of Figures 15 and 16, it can of course be positioned to be offset by the nozzle opening. After etching the ink supply channel, the polyimine 6 filling the nozzle chamber 5 uses, for example, 02 plasma to provide the nozzle assembly 100 by ashing (one of the front side ashing or the back ashing) ) was removed. Although not described above, a metal film (e.g., titanium or aluminum) can be used to protect the polymer layer 19 during the final stage of MEMS processing, as in our earlier US application Nos. 1 1 / 740, 925 and 1 1 / The contents are described in 946, 840, the contents of which are incorporated herein by reference. Typically, the -20-201020123 protective metal film is deposited on the polymer layer 19 prior to etching the nozzle opening 13. After all of the etching and oxidizing photoresist removal steps ("ashing step") have been completed, the protective metal film can be removed using a simple HF or H2 〇 2 rinse. A nozzle having a polymer bridging space between the movable portion and the stationary portion is incorporated in the nozzle assembly 100 described above, and the polymer layer 19 fills the gap between the movable portion 14 of the top plate 7 and the fixed portion 18. While this provides a good mechanical seal and can be easily fabricated, the seal structure inevitably impacts the overall performance and efficiency of the nozzle assembly. Turning to Figures 17 through 22, another alternative sequence of manufacturing steps is shown which results in a modified sealing member being bridged between the movable portion 14 and the stationary portion 18. For the sake of simplicity, the detailed components of the actuator are not shown in Figures 17 through 22. However, it will be appreciated that Figure 17 is a schematic representation of the partial formation 'nozzle assembly' shown in Figures 9 and 10, which is the starting point for this alternative sequence of fabrication steps. For the sake of clarity, like reference numerals will be used to refer to the corresponding parts in the nozzle assembly. Referring then to Figure 17, a partially formed nozzle assembly having a nozzle chamber 5 filled with polyimine 6 is shown. A top plate 7 including a thermal bending actuator (not shown in Fig. 17) forms a cover above the nozzle chamber 5. In Fig. 18, a through hole is engraved into the top plate 7 by uranium. The through hole boundary -21 - 201020123 defines a gap 17 between the movable portion 14 of the top plate 7 and the fixed portion 18. Referring next to Figure 1, the gap 17 is filled with a plug 30 of a sacrificial material such as a photoresist. The plug 30 has the function of a sacrificial gantry for depositing a polymeric sealing member in a subsequent step. In particular, the upper surface of the plug 30 defines the contour of the sealing member. The configuration of the plug 30 and the contour of its upper surface can be controlled by conventional photolithography techniques. For example, the sloped sidewalls of the plug 3 can be formed by adjusting a focus parameter during exposure of the photoresist. After forming the plug 30, the partially formed nozzle assembly is attached to a layer of flexible polymeric material 19. Typically, the polymeric material is polydimethyl siloxane (PDMS). As shown in Figure 20, the PDMS layer 19 fits the contour of the upper surface of the nozzle assembly. A protected aluminum film 31 is then deposited over the PDMS layer 19. The aluminum film 31 protects the PDMS layer 19 from an oxidizing plasma for removing the polyimide II (Fig. 22). Referring now to Figure 21, the nozzle opening 13 is then etched through the aluminum film 31, the PDMS layer 19, and the top plate 7. At different stages, this etch may require a different uranium engraving chemistry to etch through all of the two layers. Finally, and with reference to Figure 22, the nozzle assembly is subjected to an oxidizing plasma (e.g., 〇2 plasma) that removes the polyimine 6 and the photoresist plug 30. After the polyimine 6 and the plug 30 are removed by oxidation, the protected aluminum layer 31 is removed by washing in HF or H202. -22- 201020123 The completed nozzle assembly 200 shown in Fig. 22 has a sealing member 32 that bridges the movable portion 14 of the top plate 7 and the gap 17 between the fixed portions 18. Significantly, the sealing member 32 does not fill the gap 17, and in fact, does not completely lie in the space between the movable portion 14 and the fixed portion 18. The sealing member 32 has a profile of a bridge at which one end is coupled to the movable portion 14, and the other end is coupled to the fixed portion 18. Further, the bridge member generally takes the form of a single arch bridge having a ridge or raised portion 33 projecting from each end of the bridge member. Of course, depending on the contour of the upper surface of the plug 30, the sealing member can alternatively take the form of a simple beam bridge that spans between the movable portion 14 and the stationary portion 18. The sealing member 32 has several advantages over the specific embodiment shown in Figures 15 and 16, where the gap 17 is completely filled with the polymeric material 19. First, by reducing the entire volume of the polymer between the movable portion 14 and the fixed portion 18, the downward movement of the movable portion 14 has a much smaller impedance toward the substrate 1. Furthermore, the contour of the sealing member is specifically designed to facilitate the downward movement of the movable portion 14. Since the sealing member 32 takes the form of a flexible bridge member having a longer length than the movable portion 14 and the fixed portion 18, any downward movement of the movable portion 14 during actuation can be The bridge structure is easily adjusted with minimal deflection or extension of the polymeric material. Thus, the sealing member 32 provides minimal resistance to movement of the movable portion 14 while still providing an excellent seal. By minimizing the impedance of the moving portion 14 - 201020123 movement, the overall efficiency of the nozzle assembly 200, and the print head including such nozzle assemblies is improved. Of course, other configurations of the sealing member 32 are within the scope of the invention. For example, as shown in Fig. 23, the sealing member 32 can be a corrugated structure 40 having a plurality of ridges 41 and grooves 42. It should be understood that the undulating structure 40 can easily adjust the movement of the movable portion 14. It will be apparent to those skilled in the art that many variations and/or modifications may be made to the present invention, as shown in the specific embodiments, without departing from the spirit and scope of the invention as described. . Therefore, the specific embodiments of the present invention are considered in all aspects as illustrative and not restrictive. BRIEF DESCRIPTION OF THE DRAWINGS Exemplary embodiments of the present invention will now be described by way of example only with reference to the accompanying drawings in which: FIG. 1 is the side of the partially fabricated inkjet nozzle assembly after the first sequence of steps A cross-sectional view in which the nozzle chamber side walls are formed; FIG. 2 is a perspective view of the partially fabricated ink jet nozzle assembly shown in FIG. 4, and FIG. 3 is a partially formed ink jet after the second sequence of steps. A side cross-sectional view of the nozzle assembly, wherein the nozzle chamber is filled with polyimine; FIG. 4 is a perspective view of the partially fabricated ink jet nozzle assembly shown in FIG. 3; A side cross-sectional view of the partially fabricated ink jet nozzle-24-201020123 assembly, wherein the connector pillars are formed up to a chamber top plate; FIG. 6 is a partially fabricated ink jet nozzle assembly shown in FIG. Figure 7 is a side cross-sectional view of the ink jet nozzle assembly partially formed after the fourth sequence of steps, wherein a conductive metal plate is formed; Figure 8 is the partial portion shown in Figure 7. One of the inkjet nozzle assemblies Figure 9 is a side cross-sectional view of the ink jet nozzle assembly partially formed after the fifth sequence of steps, wherein the active beam member of a thermal bending actuator is formed; Figure 10 is the partial portion shown in Figure 9. A perspective view of the ink jet nozzle assembly; FIG. 11 is a side cross-sectional view of the ink jet nozzle assembly partially formed after the sixth sequence of steps, wherein one includes the movable Φ of the thermal bending actuator Figure 12 is a perspective view of the partially fabricated ink jet nozzle assembly shown in Figure 11; Figure 13 is a side cross-sectional view of the partially fabricated ink jet nozzle assembly after the seventh sequence of steps. The polymer layer is deposited and the optical cloth is 〇-| · Fig. 14 is a perspective view of the partially fabricated ink jet nozzle assembly shown in Fig. 13; Fig. 15 is a fully formed ink jet nozzle A side cross-sectional view of the assembly; -25- 201020123 Figure 1 is a perspective view of a cross-section of the ink jet nozzle assembly shown in Figure 15; Figure 17 is a partially fabricated ink jet nozzle assembly shown in Figures 9 and 10. A side cross-sectional view; Figure 18 is a etched through hole to define a room top Figure 17 shows a side cross-sectional view of the partially fabricated ink jet nozzle assembly shown in Figure 17; Figure 1 is after filling the through hole with a plug of photoresist, Figure 1 8 is a side cross-sectional view of the partially fabricated ink jet nozzle; FIG. 20 is a view of the partially formed ink jet nozzle shown in FIG. 19 after depositing a polymer layer and a protective metal layer. Figure 21 is a side elevational cross-sectional view of the partially fabricated ink jet nozzle of Figure 20 after etching a nozzle opening; Figure 22 is a side view of an ink jet nozzle assembly in accordance with the present invention; A cross-sectional view; and FIG. 2 is a side cross-sectional view of another alternative sealing member. φ [Description of main component symbols] 1 : Substrate 2 : Electrode 3 : Electrode 4 : Wall 5 : Nozzle chamber 6 : Polyimine 7 : Top plate member 26 - 201020123 8 : Connector post 9 : Metal gasket 1 〇 : Active Beam member 1 1 : nozzle opening 1 2 : beam member 1 3 : nozzle opening 1 4 : movable portion @ 1 5 : thermal bending actuator 1 6 : passive beam member 1 7 : gap 1 8 : fixed portion 19 : polymerization 20: ink supply path 2 1 : ink ejection face 30: plug φ 31 : film 3 2 : sealing member 3 3 : ridge portion 40: corrugated structure 4 1 : ridge 42 : groove 100 : ink jet nozzle Assembly 2 0 0: nozzle assembly