577817 Γ - - _ 經濟部智慧財產局員工消費合作社印製 7 8 2 6twf. doc/Ο Ο 6 八/ 五、發明說明（/ ) 本發明是有關於一種壓電式噴墨印頭及其製程，特 別是有關於一種以一金屬層及一具有槽孔之矽基底，取代 習知以陶瓷材料，用以形成壓電式噴墨印頭之振動層及墨 腔層的結構及其製程。 傳統噴墨列印技術之主要運作原理可分爲熱泡式 (Thermal bubble)及壓電式（Piezoelectric)。熱泡式噴墨 列印技術乃利用加熱器（Heater)將墨水瞬間氣化，產生 高壓氣泡推動墨水由噴嘴射出，由於熱泡式噴墨印頭之製 造成本較低，業己由HP及CANON成功地商業化，並產 生相當大的噴墨印表機市埸，但由於其高溫氣化之運作原 理，使得適用墨水（主要是水系溶劑）之選擇性低，使得 其延伸的應用領域有限。 壓電式噴墨列印技術係利用壓電陶瓷（Piezoelectric ceramic)因施加電壓而產生形變，擠壓液體產生高壓將液 體噴出。相對於熱泡式噴墨印頭，壓電式噴墨印頭具有下 列優點：壓電式噴墨印頭之墨水不會因爲高溫氣化產生化 學變化’影響顏色品質之狀況；由於不需使用反覆高熱應 力，故具有極佳的耐久性；壓電式噴墨印頭所使用之壓電 陶瓷的反應速度快，可提升列印速度，而熱泡式噴墨印頭 則會受到熱傳導速度之限制；壓電式噴墨印頭係藉由控制 電壓的大小，來控制壓電陶瓷之形變量，進而控制墨滴的 大小，可提升列印的品質。 第1圖爲習知之一種壓電式噴墨印頭之剖面示意圖。 傳統壓電式噴墨印頭100的製程係利用陶瓷厚膜（thick -----------裝 -----訂------— — (請先閱讀背面之注意事項再填寫本頁) 經濟部智慧財產局員工消費合作社印製 577817 7B26twf.doc/006 A7 --------B7____ 五、發明說明（z) film )製程形成具有上電極層102 ( upper electrode layer )、 壓電層 104 (piezoelectric layer)、下電極層 l〇6 (lower electrode layer) ' 振動層 108 ( vibrating layer)、墨腔層 110、及墨腔底膜112等陶瓷厚膜生胚（green tape)，並 依照順序將不同層的陶瓷厚膜生胚壓合黏著在一起之後， 再進行陶瓷結構的高溫燒結。例如EPSON公司所生產之 壓電式噴墨印頭。 請同樣參考第1圖，壓電式噴墨印頭100之運作原 理係藉由上電極層102及下電極層106施加電壓至壓電層 104，由於壓電層104之材質爲一壓電陶瓷（piezoelectric ceramic)，故壓電層104會受到電壓的影響而產生瞬間形 變，並藉由此瞬間形變來推移振動層108，以擠壓墨水腔 114 (pressure chamber)之中的墨水，並從出墨口 116將墨 水高壓噴射出以形成墨滴，而到達紙張表面造成圖文化。 請同樣參考第1圖，由於習知之壓電層104的寬度 均大於或等於凹槽118之橫截面的寬度，因此，當壓電層 104在頻繁地振動之下，振動層108極易沿著凹槽118之 底面四周（如圓圈所示之處）發生破裂，導致振動層108 無法正常推擠墨水腔之墨水，因而降低噴墨列印的品質。 請同樣參考第1圖，同樣由於習知之壓電層104的 寬度係大於或等於凹槽118之橫截面的寬度，使得壓電層 104接收電壓後瞬間形變所產生之振動波，極易傳達到相 緊鄰之其他噴墨印頭（未繪示），使得不噴墨之其他鄰近 噴墨印頭，受到壓電層104之振動波的影響，因而噴出些 4 本紙張尺度適用中國國家標準（CNS)A4規格（2〗0 X 297公釐） 一 , 0 --------------------訂---------線 (請先閱讀背面之注意事項再填寫本頁) 577817 A7 B7 826twf.doc/006 五、發明說明（多） 微墨滴至紙張表面’破壞原先應有之圖案文字’造成噴墨 列印品質的降低’即發生所謂交互干擾（cross-talk)的現 象， 習知之傳統壓電式噴墨印頭的製程中，除了上電極 層、下電極層採用金屬之外，其他元件均以陶瓷厚膜製程 製造完成後，再進行對位壓合黏結以及陶瓷結構的高溫燒 結。然而，傳統壓電式噴墨印頭的製程具有下列缺點： (1) 由於壓電式噴墨印頭的結構尺寸相當小，且其 結構具有較高之精密度’因而使各層陶瓷厚膜之間進行對 位壓合黏結的不良率相對提高； (2) 由於壓電式噴墨印頭的結構相當複雜，在高溫 燒結時往往因爲陶瓷材料之收縮量不均勻，造成結構上的 應力破壞，因而使成品的不良率相對提高； (3) 由於噴墨印頭的結構相當複雜，在高溫燒結時 會因爲陶瓷材料之收縮量不均勻，將致使結構設計越緻密 的噴墨印頭，其成品的良率相對降低，而無法增加噴墨印 頭之間的密度，因而限制噴墨列印的解析度。 (4) 由於習知之壓電層的寬度係大於等於凹槽之橫 截面的寬度，因此，在壓電層長時間頻繁且激烈地振動下， 使得振動層極易沿著凹槽的底面四周發生破裂，導致振動 層無法正常推擠墨水腔之墨水，因而降低噴墨列印的品 質。 (5) 由於習知之壓電層的寬度大於等於凹槽之橫截 面的寬度，將使得壓電層接收電壓後瞬間形變所產生之振 5 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） I-----------· I-----—訂-----— — (請先閱讀背面之注意事項再填寫本頁) 經濟部智慧財產局員工消費合作社印製 經濟部智慧財產局員工消費合作社印製 577817 7826twf.doc/006 A7 B7 五、發明說明（汴） 動波，極易傳達到相緊鄰之其他噴墨印頭，使得不需噴攀 之其他噴墨印頭，受到壓電層之振動波的影響，而噴出些 微的墨滴，發生交互干擾的現象，因而降低噴墨列印的品 質。 本發明之目的係爲解決上述的問題，提供一種壓電 式噴墨印頭及其製程，係利用電鍍（electroplate)及微影 (photolithography )、蝕亥丨J ( etching )的方法，形成一金 屬層及一具有槽孔的矽基底，兩者分別取代習知以陶瓷材 料製成之振動層及墨腔層，以提高成品良率及加工精密 度，降低製造成本。此外，藉由等向縮小壓電層之分佈面 積，在壓電層頻繁地振動之下，可避免金屬層在凹槽之底 面四周發生破裂，並藉此增加壓電層的振動效率，以提升 噴墨印頭的使用壽命及工作效能。 基於本發明之目的，本發明提出一種壓電式噴墨印 頭，包括一矽基底，其具有一第一面及對應之一第二面， 並具有至少一槽孔，貫穿矽基底之第一面及第二面。而金 屬層係配置於矽基底之第一面，並與矽基底構成一凹槽， 而凹槽之位置係對應於槽孔之位置。另外，鈍性金屬層係 配置於金屬層之上，而圖案化之一壓電層係配置於鈍性金 屬層之上，其中壓電層之位置係對應於凹槽之位置。而圖 案化之一上電極層係配置於壓電層之上。噴孔片則配置於 矽基底之第二面，其中噴孔片係與矽基底及金屬層構成一 墨水腔，並且噴孔片具有至少一噴孔，而噴孔係與墨水腔 相通。其中，壓電層之分佈面積係約略小於凹槽之橫截面 6 ------------^^駿--------訂-------！線^|^" Γ清先閱讀背面之注意事項再填寫本頁) 本紙張尺度適用中國國豕標準（CNS)A4規格（210 X 297公髮） 577817 7826twf.doc/006 A7 B7 五、發明說明（夕） 積。並且，位於壓電層之下方之金屬 其他位置之金屬層的厚度。 層的厚度係約略大於 基於本發明之目的，本發明提出〜 頭之製程，首先提供一砂基底，其具有〃这电式噴墨印 面，再形成一金屬層於砂基底之第〜面 ^ 面及一第二 金屬層於金屬層之上。接著，形成圖案之後形成一鈍性 性金屬層之上，再形成圖案化之一上電輪之〜壓電層於鈍 並移除部分矽基底，以形成至少一槽孔^層於壓電層上， 石夕基底之第一面及第二面，而砂基底與中槽孔係貫穿 槽，且凹槽之位置係對應壓電層之位釐屬餍構成一凹 孔片於矽基底之第二面，其中噴孔片係，取後，貼附一噴 構成一墨水腔，並且噴孔片具有至少〜噴矽基底及金屬層 相通。此外，本發明之壓電式噴墨印頭之制^其與墨水腔 壓電層之後，更包括一燒結該壓電層之步中，在形成 本發明係以電鍍的方式，利用金屬^料取代Μ 陶瓷材料而形成一金屬層，作爲噴墨印頭之振動層白由於 電鍍金屬層的成本低於陶瓷厚膜對位壓合的成本，因此可 以電鍍之金屬層作爲振動層，可降低製造成本。 本發明係以微影蝕刻的方式，在矽基底上形成槽孔， 其與金屬層構成凹槽，使得具有槽孔之矽基底可作爲噴墨 印頭之墨腔層，由於微影蝕刻所形成之尺寸精密度相當 高，故可藉此提高噴墨印頭之墨水腔結構的尺寸精密度。 本發明係藉由形成一鈍性金屬層介於金屬層及壓電 層之間’以避免在局溫燒結時’金屬層及壓幫層相互&主 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） --------^--------- (請先閱讀背面之注意事項再填寫本頁) 經濟部智慧財產局員工消費合作社印製 經濟部智慧財產局員工消費合作社印製 577817 7826twf.doc/006 A7 B7 五、發明說明（έ) 化學變化，因而影響到壓電層之應有的壓電特性。 本發明係藉由等向縮小壓電層之分佈面積/，使其小 於凹槽之橫截面積，用以避免壓電層在頻繁地振動之下， 金屬層容易沿著凹槽之底面四周而發生破裂的現象，進而 增加噴墨印頭的使用壽命。同時壓電層與金屬層可構成中 央較厚而外側較薄的結構，因而增加壓電層之振動效率， 而增加噴出墨滴的尺寸範圍，以提升噴墨印頭的工作效 會b 。 爲讓本發明之上述目的、特徵和優點能夠明顯易懂， 下文特舉一較佳實施例，並配合所附圖示，作詳細說明如 下： 圖式之簡單說明 第1圖爲習知之一種壓電式噴墨印頭的剖面示意圖； 第2A〜2D圖爲依照本發明之較佳實施例的壓電式噴 墨印頭之製程的剖面流程圖； 第3A圖及第3B圖分別爲本發明之具有寬度較窄之 壓電層之壓電式噴墨印頭的剖面示意圖及上視圖； 第4A圖及第4B圖分別爲本發明之具有增厚層之金 屬層之壓電式噴墨印頭的剖面示意圖； 第5A〜5C圖爲本發明之一種形成具有增厚層之金屬 層的剖面流程圖；以及 第6A〜6C圖爲本發明之另一種形成具有增厚層之金 屬層的剖面流程圖。 圖_式之標示說明 8 i紙張尺度細巾關家標準（CNS)A伐格（210 X 297公爱y -------------裝-------—訂· — — s (請先閱讀背面之注意事項再填寫本頁) 577817 A7 B7 7 8 2 6twf. doc/0 〇 6 五、發明說明（q) 100 :壓電式噴墨印頭 102 :上電極層 104 :壓電層 106 :下電極層 108 :振動層 110 ·墨腔層 112 :墨腔底膜 114 :墨水腔 116 :出墨口 118 :凹槽 200 :壓電式噴墨印頭. 202 :矽基底 204 :第一面 206 :第二面 208 :金屬層 209 :增厚層 210 :鈍性金屬層 212 :壓電層 214 :上電極層 216 :槽孔 218 :凹槽 220 :噴孔片 222 :墨水腔 224 :噴孔 226 :光阻層 實施例 請依序參考第2A〜2D圖，其爲依照本發明之較佳實 施例的壓電式噴墨印頭之製程的剖面流程圖。首先，如第 2A圖所示，提供一矽基底202，例如一矽晶片（siliC0n wafer)，其具有一第一面204及對應之一第二面206，並 以電鍍（electroplate)的方式，形成一金屬層208 (metal layer)於矽基底202之第一面204，再同樣以電鍍的方式， 形成一鈍性金屬層210 ( Inert metal layer)於金屬層208之 上。 如第2B圖所示，再以網版印刷（screen printing)的 方式，形成一圖案化之壓電層212 (piezoelectric layer)於 本紙張尺度適用中國國豕標準（CNS)A4規格（21〇 X 297公爱） -----------裝--------訂--------- <請先閱讀背面W注意事項再填寫本頁) 經濟部智慧財產局員工消費合作社印製 577817 7826twf.doc/006 A7 B7 經濟部智慧財產局員工消費合作社印製 五、發明說明（2) 鈍性金屬層210之上。値得注意的是，壓電層212之材質 通常爲一壓電陶瓷（Piezoelectric ceramic)，而初次網印 上之壓電層212爲一陶瓷厚膜生胚（green tape)，必須對 其進行高溫燒結，以使陶瓷厚膜生胚轉變成壓電陶瓷。其 中，壓電層212之材質包括錯銷鈦摻合物（lead zirconate titanate，PZT)或壓電高分子，又壓電高分子包括聚二氟 乙烯（Poly (Vinylidene Fluoride)，PVDF)。 如第2C圖所示，再以網版印刷的方式，形成圖案化 之一上電極層214( upper electrode layer)於壓電層212上， 而上電極層214的位置對應壓電層212的位置。由於上電 極層214是在壓電層212經過高溫燒結後，始網印上壓電 層212,因此，上電極層214之材質不需是耐高熱的導電 材料。接著，再以微影（photolithography)、触刻（etching) 的方式，移除部分矽基底202，以形成至少一槽孔216， 其貫穿矽基底202之第一面204及第二面206，並且矽基 底202與金屬層208構成一凹槽218，而凹槽218的位置 係對應於槽孔216的位置，亦對應於壓電層212的位置。 如第2D圖所示，再以貼合的方式，貼附一噴孔片220 (nozzle plate)於砂基底202之第二面206,其中噴孔片220 係封閉先前第2C圖所示之凹槽218的開口，而與矽基底202 及金屬層208共同形成墨水腔222 (pressure chamber)之 封閉空腔結構，其中噴孔片220更具有一個至數個噴孔224 (nozzle)，其分別與墨水腔222相通，用以作爲墨水的 進出口，而完成壓電式噴墨印頭200之製作。値得注意的 本紙張尺度適用中國國家標準（CNS)A4規格（210x 297公釐） -----------裝--------訂--------- (請先閱讀背面之注意事項再填寫本頁) 577817 7 8 2 6twf. doc/0 0 6 A7 B7 五、發明說明（q) 是，壓電層212若採用壓電陶瓷，而需要進行高溫燒結時， 由於噴孔片220係在壓電層212經過高溫燒結之後，始貼 附於金屬層204上，因此噴孔片220之材質不必是耐高熱 材料，而可由金屬或聚合物（polymer)之材料製作而成。 請參考第2D圖，當壓電層212之材質爲壓電陶瓷’ 而需要進彳了局溫燒結時’爲了避免尚溫燒結時丨谷化金屬層 208，因此，金屬層208之材質必須選擇熔點大於800°C以 上的金屬。此外，當以電鍍的方式形成金屬層208時，在 金屬層208內部之殘留應力容易造成結構上的應力破壞， 因此，金屬層208之材質需選擇電鍍後的殘留應力小且延 展性佳的金屬。故金屬層208之材質可包括鎳（Ni)、銅 (Cu)、鈀（Pd)、及其合金等金屬，或者是其他導電材 請同樣參考第2D圖，當壓電層212之材質採用壓電 陶瓷，而需進行高溫燒結時，爲避免壓電層212與金屬層 208兩者在高溫環境之下發生化學反應，因而破壞壓電陶 瓷之應有的壓電特性，故可利用鈍性金屬層210分隔金屬 層208及壓電層212，同樣地，爲避免鈍性金屬層210在 高溫燒結時熔化，其熔點亦需大於800°C。因此，鈍性金 屬層210之材質係可包括金（Au)、銀（Ag)、銅（Cu)、 鈾（Pt)、鈀（Pd)、其合金等金屬，或是其他導電材料。 値得注意的是，鈍性金屬層210或金屬層208均可作爲壓 電層212之下電極，即低電壓端或接地端（ground)。 爲了預防習知之兩相鄰噴墨印頭之間發生交互干擾 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） (請先閱讀背面之注意事項再填寫本頁) ▼裝-------—訂·--- 毒- 經濟部智慧財產局員工消費合作社印製 577817 A7 B7 826twf.doc/006 五、發明說明（/σ) (請先閱讀背面之注意事項再填寫本頁) (cross-talk)的現象，請同時參考第3A圖及第3B圖，其 分別爲本發明之具有寬度較窄之壓電層之壓電式噴墨印頭 的剖面示意圖及上視圖。本發明之實施例係藉由等向縮小 壓電層212之分佈面積，如箭頭方向所示，使其小於凹槽 218之橫截面積，即使得壓電層212之外側均遠離凹槽218 之橫截面的範圍（如第3B圖之虛線所示），因此壓電層212 所產生之振動波，將不易傳遞至相緊鄰之噴墨印頭的墨水 腔（未繪示），因而減少兩相緊鄰噴墨印頭之間的交互干 擾，避免不需噴墨之噴墨印頭噴出墨滴。。 請同樣參考第3A圖及第3B圖，藉由上述壓電層212 及金屬層208所組成之中央較厚而外側較薄的結構，在壓 電層212頻繁地振動之下，可以避免金屬層212沿著凹槽 218之底面四周發生破裂的現象。此外，同樣藉由此種中 央較厚而外側較薄的結構，可提高壓電層212的振動效率， 因而增加噴出墨滴的尺寸範圍。 經濟部智慧財產局員工消費合作社印製 如上所述，藉由壓電層212及金屬層208所組成之 中央較厚而外側較薄的結構，將可增加壓電層212之振動 效率。因此，爲了增加上述結構的中央厚度，以提高壓電 層212之振動效率，請同時參考第4A圖及第4B圖，其分 別爲本發明之具有增厚層之金屬層之壓電式噴墨印頭的剖 面示意圖。其中第4A圖與第3A圖不同的是，金屬層208 具有一增厚層209，其對應壓電層212之位置突出於金屬 層208，而增厚層209之面積略等於壓電層212之面積， ϋ增厚層209之材質係可與金屬層208之材質相同或不 本紙張尺度適用中國國家標準（CNS)A4規格(!10 x 297公爱） 經濟部智慧財產局員工消費合作社印製 577817 7826twf.d〇c/0〇6 A7 ____ B7 五、發明說明（"） 同。 承上所述，第4B圖與第4A圖的不同點在於，增厚 層209之分佈面積係約略大於壓電層212之分佈面積，但 小於凹槽218之橫截面積。綜上所述，第4A圖及第4B圖 之增厚層209的厚度，將使得金屬層208在壓電層212之 下方的厚度，大於其他位置之金屬層208的厚度，進而與 壓電層212之間構成一中央較厚而外側較薄的結構，以提 高壓電層212之振動效率。 爲說明如何形成第4A圖及第4B圖之具有增厚層209 的金屬層208，請依序參考第5A〜5C圖，其爲本發明之 一種形成具有增厚層之金屬層的剖面流程圖。如第5A圖 所示，在矽基底202上形成一金屬層208，再形成一光阻 層226於金屬層208上，接著利用曝光（photography)、 顯影（development)的方式，圖案化光阻層226，以暴露 需要蝕刻移除之部分金屬層208。之後，如第5B圖所示， 以半蝕刻（half etching)的方式，並未蝕穿金屬層208， 而是移除部分金屬層208之表層，使得金屬層226受到光 阻層226遮蓋之處，形成突出之一增厚層209，接著，移 除光阻層226之後，將如第5C圖所示，最後，形成一具 有增厚層209之金屬層208，即一中央厚而外側薄的金屬 層 208。 同樣爲說明如何形成第4A圖及第4B圖之具有增厚 層209的金屬層208，請依序參考第6A〜6C圖，其爲本發 明之另一種形成具有增厚層之金屬層的剖面流程圖。如第 本紙張尺度適用中國國家標準（CNS)A4規格（21〇 X 297公釐） ------------#裝--------訂---------線 (請先閱讀背面之注意事項再填寫本頁) 經濟部智慧財產局員工消費合作社印製 577817 7826twf.doc/006 ___B7 __ i、發明說明（〇 6A圖所示，在矽基底202上形成一金屬層208，再形成一 光阻層226於金屬層208上，並以曝光顯影的方式，圖案 化光阻層226。之後，如第5B圖所示，利用電鍍的方式， 以金屬層208爲種子層（seed layer)，形成一增厚層209 於光阻層226之溝渠內，再移除光阻層226，將如第5C圖 所示，最後形成一具有增厚層209之金屬層208，即形成 中央厚而外側薄的金屬層208。 依照本發明之特徵，係利用金屬取代習知之陶瓷材 料，而以電鍍的方式形成一金屬層，用以作爲噴墨印頭之 振動層。此外，以微影蝕刻的方式，在矽基底上形成至少 一槽孔，此槽孔將與先前電鍍之金屬層構成一凹槽，使得 具有槽孔之矽基底可作爲噴墨印頭之墨腔層，由於電鍍及 微影蝕刻所形成之尺寸精密度均相當高，故可藉此提升噴 墨印頭之墨水腔結構的尺寸精密度。 依照本發明之特徵，係以電鍍及微影蝕刻的方式， 形成金屬層於矽基底，並在矽基底上形成槽孔，再對位貼 合一噴孔片所構成噴墨印頭之墨水腔結構，其加工精密度 將大於習知以陶瓷厚膜對位壓合及高溫燒結後之加工精密 度，故可進一步增加噴墨印頭的密度，以提高噴墨列印之 解析度。 依照本發明之特徵，係形成一鈍性金屬層介於金屬 層及壓電層之間，以避免在高溫燒結時，金屬層及壓電層 相互發生化學變化，因而影響到壓電層之應有的壓電特 性，此外，鈍性金屬層亦可作爲壓電層之下電極。 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公t ) -------------------訂---------線· (請先閱讀背面之注意事項再填寫本頁) 577817 7826twf.doc/006 A7 B7 經濟部智慧財產局員工消費合作社印製 五、發明說明（G) 依照本發明之特徵，係等向縮小壓電層之分佈面積， 使其小於凹槽之橫截面積，用以避免壓電層在頻繁且激烈 地振動之下，金屬層沿著凹槽之底面四周而發生破裂的現 象。同時可形成壓電層與金屬層所構成中央較厚而外側較 薄的結構’用以增加壓電層之振動效率，而增加噴出墨滴 的尺寸範圍。 綜上所述’本發明之壓電式噴墨印頭之製程具有下 列優點： (1) 本發明之壓電式噴墨印頭之製程，係以金屬取 代習知之以陶瓷材料製成之振動層，以減少陶瓷材料的使 用，由於金屬之導熱性及延展性均優於陶瓷，故可改善陶 瓷於高溫燒結時，噴墨印頭之結構發生應力破壞的現象。 此外，由於金屬層之電鍍成本低於習知之陶瓷材料的對位 壓合及高溫燒結的成本，故可降低成品之製造成本。 (2) 本發明之壓電式噴墨印頭之製程’係以電鏡及 微影蝕刻的方式，形成金屬層於矽基底，並在矽基底上形 成槽孔，再對位貼合一噴孔片所構成噴墨印頭之墨水腔結 構，其加工精密度將大於習知以陶瓷厚膜對位壓合及高溫 燒結後之加工精密度，故可進一步增加噴墨印頭的密度， 以提高噴墨列印之解析度。 (3) 本發明之壓電式噴墨印頭之製程，係藉由等向 縮小壓電層之分佈面積，使其小於凹槽之橫截面積，而形 成一中央較厚而外側較薄的結構，用以避免壓電層在頻繁 且激烈地振動之下，金屬層沿著凹槽之底面四周而發生破 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） · 11----I ^« — — — — — 1 — (請先閱讀背面之注意事項再填寫本頁) 577817 7826twf.doc/006 A7 _B7_ 五、發明說明（/+) 裂的現象，故可增加噴墨印頭的使用壽命。同時形成壓電 層與金屬層所構成中央較厚而外側較薄的結構，用以增加 壓電層之振動效率，而增加噴出墨滴的尺寸範圍，以提升 噴墨印頭的工作效能。 雖然本發明已以一較佳實施例揭露如上，然其並非 用以限定本發明，任何熟習此技藝者，在不脫離本發明之 精神和範圍內，當可作些許之更動與潤飾，因此本發明之 保護範圍當視後附之申請專利範圍所界定者爲準。 (請先閱讀背面之注意事項再填寫本頁) 經濟部智慧財產局員工消費合作社印製 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐）577817 Γ--_ Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 7 8 2 6twf. Doc / Ο Ο 6 8 / V. Description of the invention (/) The present invention relates to a piezoelectric inkjet print head and its manufacturing process In particular, it relates to a structure and a process for forming a vibrating layer and an ink cavity layer of a piezoelectric inkjet print head by replacing a conventional ceramic material with a metal layer and a silicon substrate having a slot hole, and a process therefor. The main operating principles of traditional inkjet printing technology can be divided into thermal bubble and piezoelectric (piezoelectric). The thermal bubble inkjet printing technology uses a heater to instantly vaporize the ink, which generates high pressure bubbles to push the ink out of the nozzle. Due to the low manufacturing cost of the thermal bubble inkjet print head, HP and CANON have already It was successfully commercialized and produced a considerable market for inkjet printers. However, due to its high temperature gasification operation principle, the selectivity of applicable inks (mainly aqueous solvents) is low, which makes its extended application areas limited. Piezoelectric inkjet printing technology uses piezoelectric ceramics (piezoelectric ceramics) to deform due to the application of voltage, and squeezes liquid to generate high pressure to eject the liquid. Compared with thermal bubble inkjet printheads, piezoelectric inkjet printheads have the following advantages: the ink of the piezoelectric inkjet printheads will not cause chemical changes due to high temperature gasification, which affects the color quality; Repeatedly high thermal stress, so it has excellent durability; the piezoelectric ceramic used in piezoelectric inkjet print heads has a fast response speed, which can improve printing speed, while thermal bubble inkjet print heads are subject to the heat conduction speed. Limitation; Piezoelectric inkjet printheads control the deformation of piezoelectric ceramics by controlling the size of the voltage, and then the size of the ink droplets, which can improve the quality of printing. FIG. 1 is a schematic cross-sectional view of a conventional piezoelectric inkjet print head. The manufacturing process of the traditional piezoelectric inkjet print head 100 uses a ceramic thick film (thick ----------- install ----- order ----------) (Please read the Please fill out this page again) Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 577817 7B26twf.doc / 006 A7 -------- B7____ V. Description of the invention (z) film Process of forming with an upper electrode layer 102 ( upper electrode layer), piezoelectric layer 104 (piezoelectric layer), lower electrode layer 106 (lower electrode layer) 'vibrating layer 108 (vibrating layer), ink cavity layer 110, and ink cavity bottom film 112 After the green tape is pressed, the ceramic thick-film green embryos of different layers are pressed and bonded together in order, and then the ceramic structure is subjected to high-temperature sintering. For example, a piezoelectric inkjet print head produced by EPSON. Please refer to FIG. 1 as well. The operating principle of the piezoelectric inkjet print head 100 is to apply a voltage to the piezoelectric layer 104 through the upper electrode layer 102 and the lower electrode layer 106. Since the material of the piezoelectric layer 104 is a piezoelectric ceramic (Piezoelectric ceramic), the piezoelectric layer 104 will be affected by the voltage to cause instant deformation, and the instantaneous deformation will move the vibration layer 108 to squeeze the ink in the ink chamber 114 (pressure chamber) and remove The ink port 116 ejects the ink at high pressure to form ink droplets, and reaches the surface of the paper to cause a picture culture. Please refer to FIG. 1 as well. Since the width of the conventional piezoelectric layer 104 is greater than or equal to the width of the cross section of the groove 118, the vibration layer 108 can easily follow the piezoelectric layer 104 under frequent vibration. A crack occurred around the bottom surface of the groove 118 (as shown by a circle), which caused the vibration layer 108 not to normally push the ink in the ink chamber, thereby reducing the quality of inkjet printing. Please also refer to FIG. 1. Also, since the width of the conventional piezoelectric layer 104 is greater than or equal to the width of the cross-section of the groove 118, the vibration wave generated by the instant deformation of the piezoelectric layer 104 after receiving the voltage can be easily transmitted to Adjacent other inkjet print heads (not shown) make other adjacent inkjet print heads that are not inkjet affected by the vibration wave of the piezoelectric layer 104. Therefore, some 4 paper sizes are applicable to Chinese national standards (CNS ) A4 specifications (2〗 0 X 297 mm) One, 0 -------------------- Order --------- line (Please read first Note on the back, please fill in this page again) 577817 A7 B7 826twf.doc / 006 V. Description of the invention (multiple) Micro ink drops onto the surface of the paper 'destroying the original pattern text' will cause the degradation of inkjet printing quality 'to occur The so-called cross-talk phenomenon, in the conventional manufacturing process of the conventional piezoelectric inkjet print head, except that the upper electrode layer and the lower electrode layer are made of metal, after the other components are manufactured in a ceramic thick film process, Then perform para-compression bonding and high-temperature sintering of the ceramic structure. However, the manufacturing process of the traditional piezoelectric inkjet printhead has the following disadvantages: (1) Because the structure size of the piezoelectric inkjet printhead is relatively small and its structure has a high degree of precision, so the thickness of each layer of ceramic thick film The defective rate of the counter-pressure bonding is relatively increased; (2) Because the structure of the piezoelectric inkjet printhead is quite complicated, the shrinkage of the ceramic material is often uneven during high temperature sintering, which causes the structural stress to be damaged. Therefore, the defective rate of the finished product is relatively increased; (3) Because the structure of the inkjet print head is quite complicated, the shrinkage of the ceramic material is uneven during sintering at high temperature, which will cause the denser structure design of the inkjet print head. The relative yield is relatively low, which cannot increase the density between inkjet print heads, thus limiting the resolution of inkjet printing. (4) Since the width of the conventional piezoelectric layer is greater than or equal to the width of the cross section of the groove, the frequent and intense vibration of the piezoelectric layer for a long time makes the vibration layer easily occur around the bottom surface of the groove. The crack causes the vibrating layer to not normally push the ink in the ink chamber, thereby reducing the quality of inkjet printing. (5) As the width of the conventional piezoelectric layer is greater than or equal to the width of the cross section of the groove, the vibration caused by the instantaneous deformation of the piezoelectric layer after receiving the voltage will be applied. X 297 mm) I ----------- · I -----— Order -----— — (Please read the notes on the back before filling this page) Intellectual Property of the Ministry of Economic Affairs Printed by the Bureau ’s Consumer Cooperatives Printed by the Ministry of Economy ’s Intellectual Property Bureau ’s Consumer Cooperatives ’printed 577817 7826twf.doc / 006 A7 B7 V. Description of the invention (汴) Dynamic waves can be easily transmitted to other inkjet print heads next to each other, eliminating the need for Other inkjet print heads that are sprayed are affected by the vibration wave of the piezoelectric layer, and a small amount of ink droplets are ejected, which causes the phenomenon of interactive interference, thereby reducing the quality of inkjet printing. The purpose of the present invention is to solve the above-mentioned problems, and provide a piezoelectric inkjet print head and a process for forming the same by using electroplating, photolithography, and etching (J) methods. Layer and a silicon substrate with a slot, both of which replace the conventional vibrating layer and ink cavity layer made of ceramic materials, in order to improve the yield of the finished product and processing precision, and reduce manufacturing costs. In addition, by reducing the distribution area of the piezoelectric layer isotropically, under frequent vibration of the piezoelectric layer, the metal layer can be prevented from cracking around the bottom surface of the groove, thereby increasing the vibration efficiency of the piezoelectric layer to improve Inkjet print head life and performance. Based on the purpose of the present invention, the present invention proposes a piezoelectric inkjet print head, which includes a silicon substrate, which has a first surface and a corresponding second surface, and has at least one slot hole that penetrates the first of the silicon substrate. Side and second side. The metal layer is arranged on the first side of the silicon substrate and forms a groove with the silicon substrate, and the position of the groove corresponds to the position of the slot hole. In addition, a passive metal layer is disposed on the metal layer, and a patterned piezoelectric layer is disposed on the passive metal layer, where the position of the piezoelectric layer corresponds to the position of the groove. The upper electrode layer, which is patterned, is disposed on the piezoelectric layer. The nozzle plate is arranged on the second side of the silicon substrate, wherein the nozzle plate forms an ink cavity with the silicon substrate and the metal layer, and the nozzle plate has at least one nozzle hole, and the nozzle hole communicates with the ink cavity. Among them, the distribution area of the piezoelectric layer is slightly smaller than the cross section of the groove 6 ------------ ^^ 骏 -------- Order -------! Line ^ | ^ " Γ Qing first read the notes on the back before filling in this page) This paper size is applicable to China National Standard (CNS) A4 (210 X 297) 577817 7826twf.doc / 006 A7 B7 V. Invention Explanation (Eve) product. Also, the thickness of the metal layer at other positions of the metal below the piezoelectric layer. Based on the purpose of the present invention, the thickness of the layer is slightly larger than that of the present invention. The process of the present invention firstly provides a sand substrate having an electric inkjet printing surface, and then forms a metal layer on the first surface of the sand substrate. And a second metal layer on the metal layer. Next, after forming a pattern, a passivation metal layer is formed, and then a patterned one of the electric wheel ~ the piezoelectric layer is blunt and a part of the silicon substrate is removed to form at least one slot ^ layer on the piezoelectric layer. First, the first and second sides of the Shi Xi substrate, and the sand substrate and the middle slot hole penetrate the slot, and the position of the groove corresponds to the position of the piezoelectric layer. A concave hole sheet is formed on the silicon substrate. On the two sides, the spray hole sheet is attached. After being taken, a spray is attached to form an ink cavity, and the spray hole sheet has at least a spray silicon substrate and a metal layer in communication. In addition, the manufacturing of the piezoelectric inkjet print head of the present invention and the piezoelectric layer of the ink cavity further includes a step of sintering the piezoelectric layer. In forming the present invention, a metal material is used by electroplating. Instead of the M ceramic material, a metal layer is formed. As the vibrating layer of the inkjet print head, the cost of the electroplated metal layer is lower than the cost of ceramic thick film registration. Therefore, the electroplated metal layer can be used as the vibrating layer, which can reduce manufacturing. cost. The present invention forms a slot in a silicon substrate by means of lithographic etching, and forms a groove with a metal layer, so that the silicon substrate having the slot can be used as an ink cavity layer of an inkjet print head. The dimensional precision is quite high, so it can improve the dimensional precision of the ink cavity structure of the inkjet print head. In the present invention, a passive metal layer is interposed between the metal layer and the piezoelectric layer to prevent the metal layer and the pressure-reducing layer from interacting with each other during local temperature sintering. The main paper size is applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) -------- ^ --------- (Please read the precautions on the back before filling out this page) Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 577817 7826twf.doc / 006 A7 B7 V. Description of the Invention (έ) Chemical changes have affected the piezoelectric characteristics of piezoelectric layers. In the present invention, the distribution area of the piezoelectric layer is reduced by isotropically so that it is smaller than the cross-sectional area of the groove, so as to avoid the piezoelectric layer from being easily vibrated along the bottom surface of the groove under frequent vibration of the piezoelectric layer. Cracking occurs, which increases the life of the inkjet print head. At the same time, the piezoelectric layer and the metal layer can form a structure with a thicker center and a thinner outer side, thereby increasing the vibration efficiency of the piezoelectric layer and increasing the size range of the ejected ink droplets to improve the working efficiency of the inkjet print head. In order to make the above-mentioned objects, features, and advantages of the present invention comprehensible, a preferred embodiment is described below in conjunction with the accompanying drawings, and described in detail as follows: Brief Description of the Drawings Figure 1 is a conventional pressure A schematic cross-sectional view of an electric inkjet print head; FIGS. 2A to 2D are cross-sectional flowcharts of a manufacturing process of a piezoelectric inkjet print head according to a preferred embodiment of the present invention; and FIGS. 3A and 3B are the present invention, respectively. A schematic cross-sectional view and a top view of a piezoelectric inkjet print head with a narrower piezoelectric layer; Figures 4A and 4B are a piezoelectric inkjet print with a thickened metal layer according to the present invention, respectively. A schematic cross-sectional view of the head; FIGS. 5A to 5C are cross-sectional flowcharts of forming a metal layer having a thickened layer according to the present invention; and FIGS. 6A to 6C are cross-sections of forming another metal layer having a thickened layer according to the present invention; flow chart. Figure _ style label description 8 i paper size fine towels family standard (CNS) A Vage (210 X 297 public love y ------------- install ----------- Order · — — s (Please read the precautions on the back before filling this page) 577817 A7 B7 7 8 2 6twf. Doc / 0 〇6. Description of the invention (q) 100: Piezo inkjet print head 102: Top Electrode layer 104: Piezo layer 106: Lower electrode layer 108: Vibration layer 110Ink cavity layer 112: Ink cavity bottom film 114: Ink cavity 116: Ink outlet 118: Groove 200: Piezo inkjet print head. 202: Silicon substrate 204: First surface 206: Second surface 208: Metal layer 209: Thickened layer 210: Passive metal layer 212: Piezoelectric layer 214: Upper electrode layer 216: Slot 218: Groove 220: Spray Hole sheet 222: Ink cavity 224: Nozzle hole 226: Photoresist layer embodiment Please refer to Figs. 2A to 2D in sequence. This is a cross-sectional process of a piezoelectric inkjet print head according to a preferred embodiment of the present invention. First, as shown in FIG. 2A, a silicon substrate 202, such as a silicon wafer, is provided. The silicon substrate 202 has a first surface 204 and a corresponding second surface 206, and is electroplated. To form a metal A metal layer 208 is formed on the first surface 204 of the silicon substrate 202, and an inert metal layer 210 is formed on the metal layer 208 by electroplating. As shown in FIG. 2B, By screen printing, a patterned piezoelectric layer 212 (piezoelectric layer) is formed to conform to the Chinese National Standard (CNS) A4 specification (21〇X 297) in this paper size. ------- Installation -------- Order --------- < Please read the precautions on the back before filling this page) Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 577817 7826twf.doc / 006 A7 B7 Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs. 5. Description of the invention (2) On the passive metal layer 210. It should be noted that the material of the piezoelectric layer 212 is usually a piezoelectric ceramic, and the piezoelectric layer 212 on the first screen printing is a ceramic thick green tape, which must be subjected to high temperature. Sintering to transform the ceramic thick film embryo into a piezoelectric ceramic. The material of the piezoelectric layer 212 includes a lead zirconate titanate (PZT) or a piezoelectric polymer, and the piezoelectric polymer includes poly (Vinylidene Fluoride) (PVDF). As shown in FIG. 2C, a patterned upper electrode layer 214 is formed on the piezoelectric layer 212 by screen printing, and the position of the upper electrode layer 214 corresponds to the position of the piezoelectric layer 212. . Since the upper electrode layer 214 is screen-printed with the piezoelectric layer 212 after the piezoelectric layer 212 is sintered at high temperature, the material of the upper electrode layer 214 need not be a heat-resistant conductive material. Then, a part of the silicon substrate 202 is removed by photolithography and etching to form at least one slot 216 that penetrates the first surface 204 and the second surface 206 of the silicon substrate 202, and The silicon substrate 202 and the metal layer 208 form a groove 218, and the position of the groove 218 corresponds to the position of the slot 216 and the position of the piezoelectric layer 212. As shown in FIG. 2D, a nozzle plate 220 (nozzle plate) is attached to the second surface 206 of the sand base 202 in a laminating manner. The nozzle plate 220 closes the recess shown in the previous FIG. 2C. The opening of the groove 218 forms a closed cavity structure of the ink chamber 222 (pressure chamber) together with the silicon substrate 202 and the metal layer 208. The nozzle hole sheet 220 further includes one to several nozzle holes 224 (nozzle), respectively. The ink chamber 222 communicates with each other and serves as an ink inlet and outlet to complete the production of the piezoelectric inkjet print head 200.注意 Note that this paper size applies to China National Standard (CNS) A4 (210x 297 mm) ----------- installation -------- order ------- -(Please read the notes on the back before filling this page) 577817 7 8 2 6twf. Doc / 0 0 6 A7 B7 V. Description of the invention (q) Yes, if the piezoelectric layer 212 is made of piezoelectric ceramics, it needs to be done During high temperature sintering, since the orifice plate 220 is attached to the metal layer 204 after the piezoelectric layer 212 is sintered at high temperature, the material of the orifice plate 220 need not be a high heat resistant material, but can be made of metal or polymer (polymer ). Please refer to Figure 2D. When the material of the piezoelectric layer 212 is a piezoelectric ceramic, and local temperature sintering is required, in order to avoid the high temperature sintering, the metal layer 208 must be grained. Therefore, the material of the metal layer 208 must be selected. Metals with a melting point greater than 800 ° C. In addition, when the metal layer 208 is formed by electroplating, the residual stress inside the metal layer 208 is likely to cause structural stress damage. Therefore, the material of the metal layer 208 needs to be selected from metals with small residual stress after plating and good ductility. . Therefore, the material of the metal layer 208 may include metals such as nickel (Ni), copper (Cu), palladium (Pd), and alloys thereof, or other conductive materials. Please also refer to FIG. 2D. When the material of the piezoelectric layer 212 is pressed, In the case of electric ceramics, when high temperature sintering is required, in order to avoid the chemical reaction between the piezoelectric layer 212 and the metal layer 208 under high temperature environment, thus destroying the piezoelectric characteristics of piezoelectric ceramics, passive metals can be used. The layer 210 separates the metal layer 208 and the piezoelectric layer 212. Similarly, in order to prevent the passive metal layer 210 from melting during high temperature sintering, its melting point must also be greater than 800 ° C. Therefore, the material of the passive metal layer 210 may include metals such as gold (Au), silver (Ag), copper (Cu), uranium (Pt), palladium (Pd), alloys thereof, or other conductive materials. It should be noted that either the passive metal layer 210 or the metal layer 208 can be used as the lower electrode of the piezoelectric layer 212, that is, the low-voltage terminal or the ground. In order to prevent the mutual interference between the two adjacent inkjet print heads, the paper size is applicable to China National Standard (CNS) A4 (210 X 297 mm) (Please read the precautions on the back before filling this page) ▼ -------— Order · --- Poison-Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 577817 A7 B7 826twf.doc / 006 V. Description of the Invention (/ σ) (Please read the precautions on the back before (Fill in this page) (cross-talk) phenomenon, please also refer to Figures 3A and 3B, which are schematic cross-sectional views of the piezoelectric inkjet print head with a narrower piezoelectric layer of the present invention and above view. In the embodiment of the present invention, the distribution area of the piezoelectric layer 212 is reduced by isotropy, as shown by the arrow direction, so that it is smaller than the cross-sectional area of the groove 218, that is, the outer side of the piezoelectric layer 212 is far away from the groove 218. The range of the cross section (as shown by the dashed line in FIG. 3B), so the vibration wave generated by the piezoelectric layer 212 will not be easily transmitted to the ink cavity (not shown) of the inkjet print head next to it, thus reducing the two phases The interference between the inkjet print heads is close to the inkjet print heads which do not need to eject ink droplets. . Please also refer to FIG. 3A and FIG. 3B. With the thicker center and thinner outer structure composed of the above-mentioned piezoelectric layer 212 and metal layer 208, the metal layer can be avoided under the frequent vibration of the piezoelectric layer 212. The crack 212 occurs around the bottom surface of the groove 218. In addition, also with such a structure having a thicker center and a thinner outer side, the vibration efficiency of the piezoelectric layer 212 can be improved, thereby increasing the size range of the ejected ink droplets. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs As mentioned above, the piezoelectric layer 212 and the metal layer 208 have a thicker center and a thinner outer structure, which can increase the vibration efficiency of the piezoelectric layer 212. Therefore, in order to increase the central thickness of the above structure to improve the vibration efficiency of the piezoelectric layer 212, please refer to FIG. 4A and FIG. 4B, which are piezoelectric inkjets having a metal layer with a thickened layer according to the present invention, respectively. Schematic cross-section of the print head. The difference between FIG. 4A and FIG. 3A is that the metal layer 208 has a thickened layer 209, and its position corresponding to the piezoelectric layer 212 protrudes from the metal layer 208. The area of the thickened layer 209 is slightly equal to that of the piezoelectric layer 212. Area, the material of the ϋ thickened layer 209 can be the same as the material of the metal layer 208 or not. This paper size applies the Chinese National Standard (CNS) A4 specification (! 10 x 297 public love). Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs. 577817 7826twf.d〇c / 0〇6 A7 ____ B7 Fifth, the invention (") Same. As mentioned above, FIG. 4B is different from FIG. 4A in that the distribution area of the thickened layer 209 is approximately larger than that of the piezoelectric layer 212, but smaller than the cross-sectional area of the groove 218. In summary, the thickness of the thickened layer 209 in FIG. 4A and FIG. 4B will make the thickness of the metal layer 208 below the piezoelectric layer 212 larger than the thickness of the metal layer 208 at other positions, and thus the thickness of the piezoelectric layer A structure with a thicker center and a thinner outer side is formed between 212 to improve the vibration efficiency of the piezoelectric layer 212. In order to explain how to form the metal layer 208 with a thickened layer 209 in FIGS. 4A and 4B, please refer to FIGS. 5A to 5C in sequence, which is a cross-sectional flowchart of forming a metal layer with a thickened layer according to the present invention. . As shown in FIG. 5A, a metal layer 208 is formed on the silicon substrate 202, a photoresist layer 226 is formed on the metal layer 208, and then the photoresist layer is patterned by using photography and development. 226 to expose a portion of the metal layer 208 that needs to be removed by etching. Afterwards, as shown in FIG. 5B, the metal layer 208 is not etched by half etching, but a portion of the surface layer of the metal layer 208 is removed, so that the metal layer 226 is covered by the photoresist layer 226 A thickened layer 209 is formed. Next, after removing the photoresist layer 226, as shown in FIG. 5C, a metal layer 208 with a thickened layer 209 is formed, that is, a thick center and thin outer side. Metal layer 208. Similarly, to illustrate how to form the metal layer 208 with the thickened layer 209 in FIGS. 4A and 4B, please refer to FIGS. 6A to 6C in sequence, which is another cross-section of the present invention for forming a metal layer with a thickened layer. flow chart. For example, this paper size applies the Chinese National Standard (CNS) A4 specification (21 × 297 mm) ------------ # 装 -------- Order ----- ---- Line (Please read the notes on the back before filling this page) Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 577817 7826twf.doc / 006 i. Description of the invention (shown in Figure 6A, on the silicon substrate A metal layer 208 is formed on 202, and a photoresist layer 226 is formed on the metal layer 208, and the photoresist layer 226 is patterned by exposure and development. Then, as shown in FIG. 5B, electroplating is used to The metal layer 208 is a seed layer. A thickened layer 209 is formed in the trench of the photoresist layer 226, and the photoresist layer 226 is removed. As shown in FIG. 5C, a thickened layer 209 is finally formed. The metal layer 208 forms a thick metal layer 208 at the center and a thin outer side. According to the features of the present invention, a metal layer is replaced with a conventional ceramic material by metal, and a metal layer is formed by electroplating for use as an inkjet print head. Vibration layer. In addition, at least one slot is formed on the silicon substrate by lithographic etching. The metal layer forms a groove, so that the silicon substrate with the slot can be used as the ink cavity layer of the inkjet print head. Because the dimensional accuracy formed by electroplating and lithographic etching is quite high, the inkjet print head can be improved by this In accordance with the features of the present invention, a metal layer is formed on a silicon substrate by electroplating and lithographic etching, and a slot is formed on the silicon substrate, and then a nozzle plate is aligned and aligned. The precision of the ink cavity structure of the inkjet print head will be greater than the processing precision of conventional ceramic thick film registration and high temperature sintering, so the density of the inkjet print head can be further increased to improve the inkjet print head. The resolution of ink printing. According to the features of the present invention, a passive metal layer is formed between the metal layer and the piezoelectric layer to avoid chemical changes between the metal layer and the piezoelectric layer during sintering at high temperature. Affects the proper piezoelectric characteristics of the piezoelectric layer. In addition, the passive metal layer can also be used as the electrode below the piezoelectric layer. This paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 gt)- ----------------- Order --- ------ Line · (Please read the notes on the back before filling out this page) 577817 7826twf.doc / 006 A7 B7 Printed by the Consumers' Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs V. Invention Description (G) According to the invention The feature is to reduce the distribution area of the piezoelectric layer isotropically so that it is smaller than the cross-sectional area of the groove to prevent the piezoelectric layer from cracking along the bottom surface of the groove under frequent and intense vibrations. At the same time, a structure with a thicker center and a thinner outer side formed by the piezoelectric layer and the metal layer can be formed to increase the vibration efficiency of the piezoelectric layer and increase the size range of the ejected ink droplets. In summary, the process of the piezoelectric inkjet print head of the present invention has the following advantages: (1) The process of the piezoelectric inkjet print head of the present invention replaces the conventional vibration made of ceramic materials with metal. Layer to reduce the use of ceramic materials. Since the metal's thermal conductivity and ductility are better than ceramics, it can improve the phenomenon of stress damage to the structure of inkjet print heads when ceramics are sintered at high temperatures. In addition, since the plating cost of the metal layer is lower than that of the conventional ceramic materials for the alignment pressing and high-temperature sintering, the manufacturing cost of the finished product can be reduced. (2) The process of the piezoelectric inkjet print head of the present invention is to form a metal layer on a silicon substrate by means of an electron microscope and a lithographic etching, and form a slot in the silicon substrate, and then align a nozzle with the nozzle. The ink cavity structure of the inkjet print head formed by the film will have a processing precision greater than that of conventional ceramic thick film registration and high temperature sintering, so the density of the inkjet print head can be further increased to improve Resolution for inkjet printing. (3) The manufacturing process of the piezoelectric inkjet print head of the present invention is to reduce the distribution area of the piezoelectric layer isotropically so that it is smaller than the cross-sectional area of the groove, thereby forming a thicker center and a thinner outer side. Structure to prevent the piezoelectric layer from breaking under frequent and intense vibrations, and the metal layer breaks around the bottom surface of the groove. The paper size applies Chinese National Standard (CNS) A4 (210 X 297 mm) · 11 ---- I ^ «— — — — — 1 — (Please read the notes on the back before filling in this page) 577817 7826twf.doc / 006 A7 _B7_ V. Description of the invention (/ +) The phenomenon of cracking can be increased Inkjet print head life. At the same time, a structure with a thicker center and a thinner outer side formed by the piezoelectric layer and the metal layer is formed to increase the vibration efficiency of the piezoelectric layer and increase the size range of the ejected ink droplets to improve the working efficiency of the inkjet print head. Although the present invention has been disclosed as above with a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make some changes and retouch without departing from the spirit and scope of the present invention. The scope of protection of the invention shall be determined by the scope of the attached patent application. (Please read the notes on the back before filling out this page) Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs This paper size applies to China National Standard (CNS) A4 (210 X 297 mm)