Λ 3 5513twf,doc/008 A7 B7 經濟部智慧財產局員工消費合作社印裝 五、發明說明（f ) 本發明是有關於一種極化分離器之結構與製作方 法，且特別是有關於一種利用稜鏡之特性，進行低彎曲損 失的大角度彎曲，以及使用質子交換法及鎳擴散法，在鈮 酸鋰(UNb〇3)晶片上製作使τ e/TM極化分離之大角度鈮 酸鋰極化分離器的結構及其製作方法。 以往在鈮酸鋰晶片上製作之極化分離器有兩大類 型。第一類是方向耦合器式，是利用不同極化方向之模態 其耦合長度不同之原理製作而成。但兩者之耦合長度必須 滿足一定之關係式才能達到高消光比之效果，故製造時可 容忍之誤差小。第二類是Υ型分岔式，其結構爲傳統γ-型分岔，利用不同之極化光有不同偏向之特性而將Τ Ε和 ΤΜ光場分離，如中華民國專利第〇76,7〇3號與美國專利 第5,436,992號所述。但由於其利用傳統Υ-型分岔結構， 在張角大於2度時有很大的傳播損失，故以往Υ-型分岔 極化分離器的大小無法縮小。且其對於鎳擴散的製作條件 是採用高溫或長時間擴散而產生普極化方向之單極化波 導，此製作條件產生之波導對光的侷限性較差。 以往在鈮酸鋰上之Υ型極化分離器之習知製作技 術，主要是利用傳統Υ-型分岔製作方法，共包含三種製 作技術：Υ-型結構之輸入端爲一任意極化之波導，一輸 出端爲一非普極化方向之單極化波導（以氧化鎂擴散或質 子交換法製作），另一輸出端爲普極化光波導（鎳擴散）。 由於利用單極化波導之性質，元件具有很高的消光比，但 這些元件之製程需要三種之製作技術，而且傳統Υ-型結 3 本紙張尺度適用t國國家標準（CNS)A4規格（210x 297公釐） (請先閱讀背面之注意事項再填寫本頁) 裝 · -線· 5513twf.doc/008 A7 B7 經濟部智慧財產局員工消費合作社印製 五、發明說明（y) 構之角度無法大於2°，故極化分離器的大小無法縮小。且 其對於鎳擴散的製作條件是採用高溫或長時間擴散，以產 生普極化方向之單極化波導，故此製作條件產生之普極化 方向之單極化波導對光的侷限性較差。 最近幾年已有各種大角度彎曲波導在大角度彎曲下 仍有很高的傳輸率，如稜鏡式或基板式大角度彎曲波導。 其中基板式大角度彎曲波導之製作程序只須一次光罩顯影 技術，但並未利用在極化分離器上。 爲了縮小極化分離器元件所佔的面積，並解決以往 極化分離器其鎳擴散波導普極化方向單極化波導之光侷限 性不好的問題，本發明提供一種大角度之Y-型極化分離 器。其結合直波導與基板稜鏡式大角度彎曲波導而成，此 直波導是由任意極化之鎳波導所構成，大角度彎曲波導是 由質子交換波導所構成，兩者有部分重疊而形成鎳擴散質 子交換波導，且成爲Y型結構的輸入端。此輸入端必須爲 任意極化波導。 此種製程技術需要進行一次鎳金屬擴散與一次質子 交換。在γ型結構分岔處有基板稜鏡區域，利用質子交換 波導之單極化性質與基板稜鏡形狀設計，只將非普極化方 向之波偏轉’並留下普極化方向之波於鎳波導，而形成具 有相當高的消光比之極化分離器，大幅節省元件面積，提 高元件積體化之密度。再者，由於其只需要利用到任意極 化之鎳擴散波導，故其所輸出的光波在普極化方向之光波 侷限性較習知技藝要好。運用此種製程方法亦可製作一普 4 --I III---— — — It - I I I I I I I 1111.---I I (請先閲讀背面之注意事項再填窝本黃) 本紙張尺度遶用中國國家標準（CNS)A4規格<210* 297公釐） 5513twf.doc/008 A7 B7 經濟部智慧財產局員工消費合作杜印製 五、發明說明（4 ) 極化方向之單極化器。 因此本發明的主要目的就是在提供一種大角度極化 分離器的結構及其製作方法，結合任意極化之鎳擴散波導 與大角度彎曲質子交換波導，即可製作出具有高消光比與 大角度分岔之極化分離器。可大幅節省元件面積，提高元 件積體化之密度，並提供一個光侷限性佳的普極化方向之 極化器。 本發明之製程技術需要進行一次鎳金屬擴散與一次 質子交換。首先，於z切鈮酸鋰晶片上形成凹槽，並於凹 槽上形成鎳膜，再使其於溫度約爲攝氏700度至攝氏1000 度進行擴散，時間約爲10至600分鐘，以形成該任意極 化之通道式鎳波導。其次，使用製作基板稜鏡式大角度彎 曲波導之光罩，並以微影(Photolithography)與薄膜沈積等 技術，在鈮酸鋰晶片上形成作爲罩幕阻擋苯甲酸之矽罩幕 層，其中未被該矽罩幕層覆蓋之區域將與苯甲酸進行質子 交換；而此未被該矽罩幕層覆蓋之區域與該任意極化之通 道式鎳波導有約爲1毫米（millimeter)至5毫米之重疊部 份。然後，將晶片放在溫度約爲200°C至240°C的苯甲酸 中約2至24小時以進行質子交換，產生彎角約爲2°至20。 之Y字型分岔波導。最後，再利用氫氟酸將該矽罩幕層去 除。 本發明利用質子交換波導之單極化性質，以及只將 非普極化方向之波偏轉並留下普極化方向之波於鎳波導 之性質，形成具有相當高的消光之極化分離器。大幅節 ---- - II — 訂-----I I (請先閲讀背面之注項再填寫本頁) 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐〉 434426^ 5513twf.doc/0〇8 經濟部智慧財產局員工消費合作社印製 五、發明說明（e) 省元件面積，提高元件積體化之密度。 利用此設計製作出之極化分離器，有很大之張角， 大幅節省元件面積，可提高元件積體化之密度。此外， 亦具有很高之消光比及很好的光侷限性，合乎實際使用 之需要。 本發明之製程簡便，適合工業上之大量生產。 爲讓本發明之上述目的、特徵、和優點能更明顯易 懂，下文特舉較佳實施例，並配合所附圖式，作詳細說明 如下： 圖式之簡單說明： 第1圖所繪示爲依照本發明之第一實施例，一種大 角度Y-型極化分離器，其結構之剖面示意圖； 第2圖所繪示爲依照本發明之第一實施例，一種大 角度Y-型極化分離器，其結構及電磁波方向之剖面示意 圖， 第3 A圖至第3 D圖所繪示爲依照本發明之第一實 施例，一種大角度Y-型極化分離器之製作流程圖； 第4 A圖與第4 B圖所繪示爲第2圖之大角度Y-型 極化分離器的操作特性； 第5圖所繪示爲依照本發明之第二實施例，一種普 極化方向之單極化器，其結構及電磁波方向之剖面示意 圖，以及 第6A圖與第6B圖所繪示爲第5圖之普極化方向 之單極化器的操作特性。 6 ------1-------裝·! — 訂-------__線 <請先閲讀背面之注意事項再填寫本S ) 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） 經濟部智慧財產局員工消費合作社印製 3 4 4 2 6 镶 A7 5513twf . doc/008 _ B7_______ 五、發明說明（1 ) 圖示之標記說明： 10 :鎳擴散波導 12 :大角度彎曲波導 14 :鎳擴散與質子交換波導 16 :質子交換波導 18 :基板稜鏡 30 :鈮酸鋰晶片 32 :鎳 34 :矽罩幕層 36、38 :與苯甲酸進行質子交換部份 第一實施例 請參照第1圖，其所繪示的是依照本發明之第一實 施例，一種大角度Y-型極化分離器’其結構之剖面示意 圖。其中大角度Y-型極化分離器包括有直波導1 〇與基 板稜鏡式大角度彎曲波導1 2。此直波導1 0例如是由 任意極化之鎳波導所構成，而大角度彎曲波導1 2中則 包括鎳擴散與質子交換波導1 4、質子交換波導1 6與 基板稜鏡18等部分。在鎳擴散與質子交換波導14與 質子交換波導1 6的交接處具有基板稜鏡1 8，分別與 鎳擴散與質子交換波導14及質子交換波導16耦接。 如圖所示，由於此基板稜鏡區1 8在鎳擴散波導1 〇範 圍內，故基板稜鏡18之折射率與鎳擴散波導1〇相等， 但遠小於質子交換波導1 6的折射率，因此可以基板稜 鏡1 8加速非普極光之波前的前進速度，運用基板稜鏡 本紙張尺度適用中國國家標準（CNS)A4規格（210x 297公釐） ----------— I* 裝----一訂---------線* (請先閲讀背面之注意事項再填寫本頁) A7 55i3twf.doc/008 37 經濟部智慧財產局員工消费合作社印製 五、發明說明（&) 式大角度彎曲波導1 2中，位於鎳擴散與質子交換波導 1 4與質子交換波導1 6交接處之基板稜鏡1 8，由於 經過基板稜鏡1 8內側與外側之加速區長度不一樣，因 此光波通過波導內外側時會產生相位差，藉此以改變光 波前方向，進而達成大角度彎曲之目的。此種大角度γ_ 型極化分離器結構之輸入端分爲兩個部分：其中一部份 爲鎳擴散直波導1 0，另一個部份則爲鎳擴散與質子交 換重疊區1 4，這兩固區域皆必須爲任意極化光波導。 由於質子交換法會降低鈮酸鋰普極化方向之折射率，故 必須控制鎳擴散條件與質子交換條件，以達到使重疊區 14具有任意極化特性之目的。基板稜鏡區18之內外 側長度L滿足下列關係： {nf-ns)L = 2neffW tan A ^ id H j· 其中w爲波導寬度，化爲波導折射率，心爲基板折射率， neff波導等效折射率，Θ爲彎曲角度。 如第2圖所示，其爲依照本發明之第一實施例，一 種大角度Y-型極化分離器，其結構及電磁波方向之剖面 示意圖。第2圖所示爲一種製造於Z切鈮酸鋰晶片上之極 化分離器，其鎳擴散波導1 0與質子交換波導1 6之分岔 角（夾角）爲7度。 再請參照第3A圖至第3D圖，其所繪示的是依照 本發明之第一實施例，一種大角度Y-型極化分離器之製 作流程圖。由於鎳擴散波導1 0之製作溫度比鎳擴散與質 子交換波導1 4以及質子交換波導1 6之製作溫度高，所 8 (請先閱讀背面之注項再填窝本頁) 本紙張尺度適用中國國家標準（CNS)A4規格（210 * 297公釐） 43^426^ 55l3twf.doc/C08 五、發明說明（ο ) 以先進行鎳擴散波導1 0之製作。 (諳先閱讀背面之注意事項再填寫本頁) 經濟部智慧財產局貝工消費合作社印製 首先，請參照第3 A圖，在Z切鈮酸鋰晶片3 0上， 進行微影製程，利用光罩蝕刻術蝕刻出長條形狀之凹槽， 然後再進行薄膜沈積，在凹槽上鍍鎳，形成4微米（micron) 寬、300埃（angstrom)厚的鎳3 2。接著，如第3 B圖所示， 將鈮酸鋰晶片3 0置於溫度約爲攝氏800度的環境下進行 擴散，時間約爲一小時，使得位於鈮酸鋰晶片3 0上凹槽 中的鎳3 2擴散，形成一條直的任意極化鎳擴散波導1 ◦。然後，請參照第3 C圖，使用製作基板式彎曲波導之 光罩進行微影步驟，以蝕刻技術、剝離技術與真空技術， 於鈮酸鋰晶片3 0上形成作爲罩幕用來阻擋苯甲酸的矽罩 幕層3 4，其沒有被矽罩幕層3 4覆蓋的質子交換部份3 6與3 8將與苯甲酸進行質子交換。其中未被矽覆蓋的質 子交換部份3 6與先前之鎳擴散波導1 〇重疊，重疊長度 爲4毫米。然而，此未被矽覆蓋的質子交換部份3 6與3 8經質子交換之後，即爲鎳擴散與質子交換波導1 4與質 子交換波導1 6。接著，再參照第3 D圖，將整個鈮酸鋰 晶片3 0放在溫度約爲攝氏240度的苯甲酸中約8小時進 行質子交換，藉以產生彎角約爲7度的彎曲波導1 2。最 後再將矽罩幕層3 4去掉，例如使用氫氟酸去除罩幕層。 如第4A圖與第4 B圖所示，其爲第2圖之大角度 Y -型極化分離器的操作特性，第4 A圖及第4 B圖分別 爲極化方向與Z軸成90°、0°之光訊號。從第4 B圖上可 以看出當極化方向與Z軸成0°時，只有分支2，即鎳擴散 9 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） 4 34426^ A7 5513twf.doc/008 37 五、發明說明（） 波導1 0有訊號。而極化方向與Z軸成90°時，只有分支 1，亦即僅質子交換波導1 6有訊號。而TE與TM模態之 消光比在0.6328微米分別爲26dB與28dB，其TE方向的 傳輸率爲25%，其TM方向之傳輸率爲40%。 第二實施例 請參照第5圖，其所繪示的是依照本發明之第二實 施例，一種普極化方向之單極化器，其結構及電磁波方向 之剖面示意圖。其中鎳擴散波導1 0與質子交換波導1 6 之張角（夾角）約爲7度。其結構雖然與第2圖一樣，但 其光波之輸出只由鎳擴散波導1 0輸出，成爲一普極化方 向之極化器。其製造流程與第一實施例，而其製程條件如 表一所不。 ------ ------- -----1— 訂--—------線 — (請先閲讀背面之注意事項再填寫本頁) 表一普極化方向; 極化器之製作^ i件 mn 竄庠 溫度 時間 鏜墉散 lam 800°C 65min 皙子夺梅 9 am 240〇C 9hr 經濟部智慧財產局員工消費合作社印製 第5圖之普極化方向之單極化器的操作特性如第6 A圖及第6 B圖所示，其中第6 A圖與第6 B圖分別爲極 化方向與Z軸成0°、90°時之光訊號。從第6 A圖與第6 B圖可以看出當極化方向與Z軸成90°時，輸出TE方向 之訊號，而當極化方向與Z軸成0°時，沒有訊號，即無TM 方向之訊號，其消光比在0.6328微米爲24dB。 由上述本發明之較佳實施例可知，應用本發明至少 本紙張尺度適用中國國家標準（CNS)A4規格（210x 297公釐） 213 4426一 A7 5513twf.doc/008 B7 經濟部智慧財產局員工消費合作社印製 五、發明說明） 具有下列優點： 1.應用本發明製作之極化分離器，其具有較大的張 角，可大幅節省元件所需使用的面積，以提高元件積體化 之密度。 應用本發明製作之鎳擴散式極化分離器，具有很高 的消光比，符合實際使用之需要。 3. 應用本發明製作之普極化方向之單極化器，具有很 高的消光比，而且具有很好的光侷限性。 4. 應用本發明之極化分離器，其製程簡便，可適用於 產業上之大量生產。 雖然本發明已以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，當可作各種之更動與潤飾，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。Λ 3 5513twf, doc / 008 A7 B7 Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs. 5. Description of the invention (f) The present invention relates to the structure and manufacturing method of a polarized separator, and in particular to a utilization edge Mirror characteristics, large-angle bending with low bending loss, and the use of proton exchange and nickel diffusion methods to fabricate large-angle lithium niobate poles with τ e / TM polarization separation on a lithium niobate (UNb03) wafer Structure of a chemical separator and manufacturing method thereof. There are two main types of polarization separators previously fabricated on lithium niobate wafers. The first type is the directional coupler type, which is made by using the principle of different polarization directions and different coupling lengths. However, the coupling length of the two must satisfy a certain relationship to achieve the effect of high extinction ratio, so the error that can be tolerated during manufacturing is small. The second type is a Υ-type bifurcation type. Its structure is a traditional γ-type bifurcation. It uses the characteristics of different polarized light to have different deflections to separate TE and TM light fields, such as the Republic of China Patent No. 076,7. No. 03 and U.S. Patent No. 5,436,992. However, because it uses the traditional Υ-type bifurcation structure, there is a large propagation loss when the opening angle is greater than 2 degrees, so the size of the conventional Υ-type bifurcation polarization separator cannot be reduced. Moreover, the manufacturing conditions for nickel diffusion are high temperature or long-term diffusion to produce single-polarized waveguides in the direction of normal polarization. The waveguides produced under these manufacturing conditions have relatively limited limitations on light. In the past, the conventional manufacturing technology of the rubidium-type polarization separator on lithium niobate mainly uses the traditional rubidium-type bifurcation manufacturing method, which contains three manufacturing technologies: the input end of the rubidium-type structure is an Waveguide, one output end is a single-polarized waveguide with non-normal polarization direction (made by magnesium oxide diffusion or proton exchange method), and the other output end is a general-polarized optical waveguide (nickel diffusion). Due to the use of the properties of single-polarized waveguides, the components have a high extinction ratio, but the manufacturing process of these components requires three manufacturing techniques, and the traditional Υ-type junction 3 This paper size is applicable to the national standard (CNS) A4 specification (210x 297 mm) (Please read the precautions on the back before filling out this page) Installation · -line · 5513twf.doc / 008 A7 B7 Printed by the Employees' Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 5. The description of the invention (y) More than 2 °, the size of the polarization separator cannot be reduced. Moreover, the fabrication conditions for nickel diffusion are high temperature or long-term diffusion to produce single-polarized waveguides in the normal polarization direction. Therefore, the single-polarized waveguides in the normal polarization direction produced by these production conditions have relatively limited light limitations. In recent years, various high-angle curved waveguides have a high transmission rate under large-angle bending, such as a 稜鏡 -type or substrate-type large-angle curved waveguide. The manufacturing process of the substrate-type large-angle curved waveguide requires only one mask development technique, but it is not used in the polarization separator. In order to reduce the area occupied by the polarization splitter element, and to solve the problem of poor light limitation of the conventional polarization splitter in the conventional polarization direction of the single polarization waveguide of the nickel diffusion waveguide, the present invention provides a large-angle Y-type Polarization separator. It is a combination of a straight waveguide and a substrate-type large-angle curved waveguide. This straight waveguide is composed of a randomly polarized nickel waveguide. The large-angle curved waveguide is composed of a proton exchange waveguide. The two are partially overlapped to form nickel. The diffused proton exchange waveguide becomes the input end of the Y-shaped structure. This input must be an arbitrary polarized waveguide. This process technology requires a nickel metal diffusion and a proton exchange. There is a substrate 稜鏡 region at the bifurcation of the γ-type structure. The unipolar nature of the proton exchange waveguide and the shape of the substrate 稜鏡 are used to deflect the waves in the non-normal polarization direction and leave the waves in the normal polarization direction. The nickel waveguide forms a polarization splitter with a relatively high extinction ratio, which greatly saves the area of the component and increases the density of the integrated component. In addition, since it only needs to use an arbitrarily polarized nickel diffusion waveguide, its output light waves are more limited in the direction of normal polarization than conventional techniques. Using this process method can also make a general 4 --I III ------It-IIIIIII 1111. --- II (Please read the precautions on the back before filling in the original yellow) This paper scale uses China National Standard (CNS) A4 Specification < 210 * 297 mm) 5513twf.doc / 008 A7 B7 Consumption Cooperation between Employees and Intellectual Property Bureau of the Ministry of Economic Affairs. Du V. Description of Invention (4) A single polarizer in the direction of polarization. Therefore, the main object of the present invention is to provide a structure of a large-angle polarization splitter and a manufacturing method thereof. By combining a randomly diffused nickel diffusion waveguide and a large-angle curved proton exchange waveguide, a high extinction ratio and a large angle can be manufactured. Bifurcation polarization separator. It can greatly save the component area, increase the density of component integration, and provide a polarizer with a normal polarization direction with good optical limitations. The process technology of the present invention requires a nickel metal diffusion and a proton exchange. First, a groove is formed on a z-cut lithium niobate wafer, and a nickel film is formed on the groove, and then it is diffused at a temperature of about 700 ° C to 1000 ° C for a time of about 10 to 600 minutes to form The arbitrarily polarized channel nickel waveguide. Secondly, using a mask for manufacturing a substrate-type large-angle curved waveguide, and using techniques such as photolithography and thin film deposition, a silicon mask layer as a mask to block benzoic acid was formed on a lithium niobate wafer. The area covered by the silicon mask curtain layer will be proton exchanged with benzoic acid; and the area not covered by the silicon mask curtain layer and the arbitrarily polarized channel nickel waveguide are about 1 millimeter to 5 millimeters. Overlapping parts. The wafer is then placed in benzoic acid at a temperature of about 200 ° C to 240 ° C for about 2 to 24 hours for proton exchange, resulting in a bend angle of about 2 ° to 20 °. Y-shaped bifurcated waveguide. Finally, the silicon mask layer was removed with hydrofluoric acid. The invention utilizes the single polarization property of the proton exchange waveguide and the property of deflecting only the waves in the non-normal polarization direction and leaving the waves in the normal polarization direction to the nickel waveguide to form a polarization splitter with relatively high extinction. Large section -----II — Order ----- II (Please read the note on the back before filling this page) This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) 434426 ^ 5513twf.doc / 0〇 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs. 5. Description of the Invention (e) Save the component area and increase the density of component integration. The polarization separators produced by this design are very large. The opening angle greatly saves the area of the component, and can increase the density of the integrated component. In addition, it also has a high extinction ratio and good light limitations, which is in line with the needs of practical use. The process of the invention is simple and suitable for industrial applications. Mass production. In order to make the above-mentioned objects, features, and advantages of the present invention more comprehensible, the preferred embodiments are described below in detail with the accompanying drawings as follows: Brief description of the drawings: Figure 1 Shown is a cross-sectional view of the structure of a large-angle Y-type polarization separator according to the first embodiment of the present invention; FIG. 2 is a view of a large-angle Y according to the first embodiment of the present invention -Type polarization separator, which Sectional schematic diagrams of the structure and the direction of the electromagnetic wave. Figures 3A to 3D show the flow chart of manufacturing a large-angle Y-type polarization separator according to the first embodiment of the present invention; Figure 4A and Figure 4B shows the operating characteristics of the large-angle Y-type polarization separator shown in Figure 2; Figure 5 shows a single polarization in the general polarization direction according to the second embodiment of the present invention Device, a schematic cross-sectional view of its structure and electromagnetic wave direction, and the operating characteristics of a single polarizer shown in Figures 6A and 6B as the normal polarization direction of Figure 5. 6 ------ 1-- ----- Install ·! — Order -------__ line < Please read the notes on the back before filling in this S) This paper size applies to China National Standard (CNS) A4 (210 X 297 Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 3 4 4 2 6 inlaid with A7 5513twf .doc / 008 _ B7_______ V. Description of the invention (1) Graphical description of the mark: 10: Nickel diffusion waveguide 12: Large-angle bending Waveguide 14: Nickel diffusion and proton exchange waveguide 16: Proton exchange waveguide 18: Substrate 稜鏡 30: Lithium niobate wafer 32: Nickel 34: Silicon mask curtain layers 36, 38 : The first embodiment of the proton exchange with benzoic acid Please refer to FIG. 1, which shows a schematic cross-sectional view of the structure of a large-angle Y-type polarization separator according to the first embodiment of the present invention. . The high-angle Y-type polarization splitter includes a straight waveguide 10 and a substrate-type large-angle curved waveguide 12. The straight waveguide 10 is made of, for example, an arbitrarily polarized nickel waveguide, and the high-angle curved waveguide 12 includes nickel diffusion and proton exchange waveguides 14, a proton exchange waveguide 16 and a substrate 稜鏡 18. A substrate 稜鏡 18 is provided at the junction of the nickel diffusion and proton exchange waveguide 14 and the proton exchange waveguide 16 and is coupled to the nickel diffusion and proton exchange waveguide 14 and the proton exchange waveguide 16, respectively. As shown in the figure, since the substrate region 18 is within the range of the nickel diffusion waveguide 10, the refractive index of the substrate region 18 is the same as that of the nickel diffusion waveguide 10, but is much smaller than the refractive index of the proton exchange waveguide 16, Therefore, the substrate can accelerate the forward speed of non-universal aurora wavefronts. Using the substrate, the paper size applies the Chinese National Standard (CNS) A4 specification (210x 297 mm) ---------- — I * Installation ---- One Order --------- Line * (Please read the precautions on the back before filling out this page) A7 55i3twf.doc / 008 37 Printed by the Consumers ’Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 5. In the & wide-angle curved waveguide 12 of the invention, the substrate 稜鏡 1 8 at the junction of the nickel diffusion and proton exchange waveguide 14 and the proton exchange waveguide 16 is passed through the inside of the substrate 稜鏡 18. The length of the acceleration zone is different from that of the outer side, so a phase difference occurs when the light wave passes through the inner and outer sides of the waveguide, thereby changing the direction of the light wavefront, thereby achieving the purpose of large-angle bending. The input of such a large-angle γ_-type polarization splitter structure is divided into two parts: one part is a nickel diffusion straight waveguide 10, and the other part is a nickel diffusion and proton exchange overlap region 14. The solid region must be an arbitrary polarized optical waveguide. Since the proton exchange method reduces the refractive index in the normal polarization direction of lithium niobate, the nickel diffusion conditions and proton exchange conditions must be controlled to achieve the purpose of making the overlap region 14 have arbitrary polarization characteristics. The length L of the inner and outer sides of the substrate region 18 satisfies the following relationship: {nf-ns) L = 2neffW tan A ^ id H j · where w is the waveguide width, which is converted into the waveguide refractive index, the core is the substrate refractive index, the neff waveguide, etc. Effective refractive index, Θ is the bending angle. As shown in FIG. 2, it is a schematic cross-sectional view of the structure and electromagnetic wave direction of a large-angle Y-type polarization separator according to the first embodiment of the present invention. Fig. 2 shows a polarized separator manufactured on a Z-cut lithium niobate wafer. The bifurcation angle (angle) between the nickel diffusion waveguide 10 and the proton exchange waveguide 16 is 7 degrees. Please refer to FIG. 3A to FIG. 3D again, which show a manufacturing flow chart of a large-angle Y-type polarization separator according to the first embodiment of the present invention. Because the manufacturing temperature of nickel diffusion waveguide 10 is higher than the manufacturing temperature of nickel diffusion and proton exchange waveguide 14 and proton exchange waveguide 16, so 8 (Please read the note on the back before filling this page) This paper is applicable to China National Standard (CNS) A4 Specification (210 * 297 mm) 43 ^ 426 ^ 55l3twf.doc / C08 5. Description of the Invention (ο) The nickel diffusion waveguide 10 is first produced. (谙 Please read the notes on the back before filling this page) Printed by the Shellfish Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs First, please refer to Figure 3A, and perform a lithography process on a Z-cut lithium niobate wafer 30, using The photolithography etched a long groove, and then thin film deposition was performed. Nickel was plated on the groove to form 4 micron wide and 300 angstrom thick nickel 3 2. Next, as shown in FIG. 3B, the lithium niobate wafer 30 is diffused in an environment with a temperature of about 800 degrees Celsius for about one hour, so that the lithium niobate wafer 30 located in the groove on the lithium niobate wafer 30 Nickel 3 2 diffuses to form a straight arbitrary polarized nickel diffusion waveguide 1 ◦. Then, referring to FIG. 3C, a lithography step is performed using a mask for manufacturing a substrate-type curved waveguide. An etching technique, a peeling technique, and a vacuum technique are used to form a mask on the lithium niobate wafer 30 as a mask to block benzoic acid. The silicon mask curtain layer 3 4 whose proton exchange portions 36 and 38 are not covered by the silicon mask curtain layer 3 4 will undergo proton exchange with benzoic acid. Among them, the proton exchange part 36 not covered by silicon overlaps with the previous nickel diffusion waveguide 10, and the overlap length is 4 mm. However, after the proton exchange portions 36 and 38 not covered by silicon are proton exchanged, they are the nickel diffusion and proton exchange waveguides 14 and 16. Next, referring to FIG. 3D again, the entire lithium niobate wafer 30 is placed in benzoic acid at a temperature of about 240 ° C for about 8 hours for proton exchange, thereby generating a curved waveguide 12 with a bend angle of about 7 °. Finally, the silicon mask layer 34 is removed, for example, using hydrofluoric acid to remove the mask layer. As shown in Figures 4A and 4B, it is the operating characteristics of the large-angle Y-type polarization separator of Figure 2. Figures 4A and 4B show that the polarization direction is 90 ° to the Z axis, respectively. °, 0 ° light signal. From Figure 4B, it can be seen that when the polarization direction is 0 ° with the Z axis, there are only branches 2, that is, nickel diffusion. 9 This paper size is applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 mm). 4 34426 ^ A7 5513twf.doc / 008 37 V. Description of the invention () The waveguide 10 has a signal. When the polarization direction is 90 ° to the Z axis, only branch 1 is present, that is, only proton exchange waveguide 16 has a signal. The extinction ratios of TE and TM modes are 26dB and 28dB at 0.6328 microns, respectively. The TE direction transmission rate is 25% and the TM direction transmission rate is 40%. Second Embodiment Please refer to FIG. 5, which shows a schematic cross-sectional view of the structure and electromagnetic wave direction of a unipolarizer with a normal polarization direction according to a second embodiment of the present invention. The opening angle (angle) between the nickel diffusion waveguide 10 and the proton exchange waveguide 16 is about 7 degrees. Although its structure is the same as that in Figure 2, the output of its light wave is only output by the nickel diffusion waveguide 10, and it becomes a polarizer with a normal polarization direction. The manufacturing process is the same as the first embodiment, and the manufacturing conditions are as shown in Table 1. ------ ------- ----- 1— Order --------- Line — (Please read the notes on the back before filling this page) Orientation; production of polarizers ^ i mn channeling temperature time boring lam 800 ° C 65min Xizi won the plum 9 am 240 0C 9hr Printed in Figure 5 by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs The operating characteristics of the unipolarizer in the direction are shown in Figures 6A and 6B, where Figures 6A and 6B are the optical signals when the polarization direction is 0 ° and 90 ° with the Z axis, respectively. . From Figures 6A and 6B, it can be seen that when the polarization direction is 90 ° with the Z axis, a signal in the TE direction is output, and when the polarization direction is 0 ° with the Z axis, there is no signal, that is, there is no TM Directional signals have an extinction ratio of 24dB at 0.6328 microns. From the above-mentioned preferred embodiments of the present invention, it can be known that the application of the present invention applies at least this paper size to the Chinese National Standard (CNS) A4 specification (210x 297 mm) 213 4426 a A7 5513twf.doc / 008 B7 employee consumption of the Intellectual Property Bureau of the Ministry of Economic Affairs Printed by the cooperative 5. Description of the invention) It has the following advantages: 1. The polarization separator produced by applying the invention has a large opening angle, which can greatly save the area required for the component, and increase the density of the component integration. The nickel diffusion-type polarization separator produced by applying the invention has a high extinction ratio, which meets the needs of practical use. 3. The single-polarizer with the normal polarization direction made by the present invention has a high extinction ratio and good optical limitations. 4. The polarization separator of the present invention has a simple process and can be applied to mass production in the industry. 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 various modifications and retouches without departing from the spirit and scope of the present invention. Therefore, the present invention The scope of protection shall be determined by the scope of the attached patent application.
I I 本紙張尺度適用尹國國家棉準（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)I I This paper size is applicable to Yin Guo National Cotton Standard (CNS) A4 (210 X 297 mm) (Please read the precautions on the back before filling this page)