1303495 九、發明說明： 【發明所屬之技術領域】 本發明係關於一種發先 組成構件以增進它們的光輪 元件；特別是有關於一出率。 種新的 【先前技術】 發光、二極體兀件係將電能轉化為光的重要固熊元 件’其通常具有-半導體主動層夾於其它層之間。隨 導體材料品質的提昇，發光二極體元件的發光效率亦隨^ 提南。市售的發光二極體it件係由銦、銘、鎵與氮的合金 (AlInGaN)所製作形成。這些合金使得發光二極體元& 於紫外光至綠光光譜區成為可行。然而，發光二極體元 的發光效率係受限於其無法耦合發光二極體晶片主動層所 產生的所有光。當一發光二極體元件被能量激發時，其主 動層會朝各個方向發光，以許多不同的角度抵達發光^極 體元件表面。典型的半導體材料具有一相較於空氣(η^·〇) 或環氧樹脂包覆層（η4·5)還高的折射係數。根據斯涅耳定 律(Snell’s law)，光從折射係數〜的材料經過入射於較低折 射係數h的材料時，當其入射角小於相對於入射面^線的 一臨界角時，光會穿經該較低折射係數的材料，其中 0c=sin Wns) ⑴。 當光抵達半導體表面的入射角大於時，會產生内部 全反射。光會被反射回到發光二極體晶片内部而可能於發 光二極體晶片内部或貼附於該晶片的金屬接觸層被吸收。 對於傳統的發光二極體元件，其結構内部產生的大部份光 在離開半導體晶片之前往往遭遇内部全反射。以傳統採用 藍寶石基底的氮化鎵發光二極體元件為例，百分之七十的 1303495 發射光係被束缚於藍寶石基底與氮化鎵的外部表面之間。 此發射光係重覆被反射，而大為提高被再吸收及損失的機 會。 已經有一些技術被提出來以提高發光二極體元件的光 萃取率（light extraction)。提供具有反射接觸層的發光二極體 元件即為其中一例。由於被束缚於結構内部並入射於金屬 接觸層的光將會被反射回到元件内部而非被吸收，因而可 提高發光二極體元件的發光效率。此一現象亦使得光擁有 另一機會於下次入射於發光二極體元件表面時，可逃離該 發光二極體晶片。雖然反射接觸層提高光萃取率，傳統的 發光二極體元件仍然有嚴重的光損失。韃化頂部表面係提 高光萃取率的另一種技術。糙化的散射子（R0Ughening scatters)使得反射光呈任意角度反射，而使得受束缚的光改 變光徑。藉由平行的界面，亦可阻止光重覆反射。部份的 散射光因而在被吸收之前有機會以小於内部全反射臨界角 的入射角入射於一表面。典型半導體層係呈薄膜狀，因此 僅有細微尺寸的链化可行。再者’链化表面（roughening surface)會引起發光二極體元件製程的其它問題。例如，接 觸縫化表面即是一個問題。再者，糙化表面會使得光罩對 準晶圓變得困難。糙化表面使得用來焊接及檢查晶圓的圖 案辨識設備（pattern recognition equipment)難以適當的工 作。因此，另一種可改變受束縛光光徑的技術成為需求。 用以散射受束缚光的另一種技術係於氮化鎵與其下方基底 之間提供一链化界面’可於長成半導體層之前，藉由圖案 蝕刻及糙化基底來完成。上述技術可有效提高光萃取率。 然而，該基屁的紋理化表面會影響後續該等半導體層的成 長。對於該等半導體層的品質常有不利的影響，其成長再 現性亦變差。 其他提高光輸出率的方法係揭露於美國專利第 1303495 6,657,236 5虎’在比藉其蒼考專利號涵括全文於本文中。美 國專利第6,657,236號及美國專利第6,821，804號教示另二 種方法，其使用具N型#質的氮化鎵銦紹材料形成的一第 一擴散層（a first spreading layer)，及一第二擴散層，較佳係 一半透光金屬薄層，例如叙、鉑、把/鉑、鈀/金、鎳/金、氧 化鎳/金或其等組合物，較佳沈積在p型氮化鎵銦铭表面 上。光萃取元件的結構可設計成光萃取元件陣列或多重散 射子層（disperser layers)。光萃取元件可由折射係數較高於 元件包覆材料折射係數的材質形成。 ' 美國專利第6,831，302號教示一種結構係包含一多層材 貝豐層、可反射至少約百分之五十入射光的一反射層，及 其中一具N型摻質材料的表面，例如n型氮化鎵的表面， • 具有隨著某一圖案而產生空間上變化的介電功能。美國專 利申晴案公開第2005/0227379號教示使用雷射使一半導體 、 層表面成形，以提高光萃取率。此外，基底上可含有三維 • 的光萃取幾何圖案，或者形成於基底上的一發光元件I含 至少一圖案層以產生光萃取特性。 所有的已知技術不是僅僅稍微改善光萃取效率，就是 製造費用高昂，或者兩樣具備。因此，亟待提出一種可提 • 咼發光元件發光強度並且製造費用低廉的簡單解決方法。 【發明内容】 本發明之目的係提供一種價格低廉、具增進的光萃取 率（light extraction efficiency)的元件結構。相反於習知技 術，發光元件的主要半導體部並未作改變，因此所有的電 流發光二極體或其它發光元件結構可採用本發明的優點。 藉由提供一介質，如同一鍍層，本發明可提高發光二極體 元件的光卒取率，光可輕易地進入及穿過該介質並產生最 小的光減損。該介質的表面可以經設計以利於光離開元件 1303495 氣或：包覆層。另外’本發明藉*大大增加元件的 表面積以提咼光萃取率。 .本發明提f —介質，例如折射係數及消光係數(Hght extmctHHi CGeffieiene)〇 皆在__ Γ，形成於—固態發光元件的-個表面或多“Ξί Η亥介電It層的折射係數接近或大於發光面時，在發光面/ 介電鍍層之界面僅產生最小的弗藍斯涅耳反射 邊ctions)。再者，光進人該介電縣的臨界角將接近九 十度’使來自半導體層的相當高比率的發光可以進入該介 電鑛層。當該介電鍍層具有料低損失時，光即可穿明 層而無觀的光損失。再者，t該介電鑛層被糙化或適當 地圖案侧’發光面積即可提高。相較於許多半導體層， 該介電錄層可製作的較厚’因此與—般在半導體上的餘刻 圖案比較起來，該介電鍍層上可形成較大尺寸的圖宰。如 此一來，光子具有更多的機會撞擊於光萃取表面，而非被 反射回到使光減損的半導體層或金屬層内部。折射係數大 於氮化鎵的材料的一個例子是碳化矽(smc〇n carbide)，其 可以電漿化學氣相沈積方法（plasma_enhanced chemical vapor deposition)沈積0 在一實施例中，該介電介質係一鍍層形成在一發光元 件的頂層以提高該元件的光萃取率。該鍍層具有低光學損 失及折射係數約為2或更南，較佳具有一折射係數接近或 大於半導體頂層，例如氮化鎵銦鋁材料系統的氮化鎵。該 鍍層可以是下列金屬氧化物群組中任一材質或其組合：五 氡化二组(Ta2〇5)、五氧化二銳(Nb2〇5)、二氧化鈦（Ti〇2)。 其它的材質亦是可行，例如碳化矽（silicon carbide)及氮化 叙固怨浴液(GaN based solid solutions)。該鐘層的厚度範圍 1303495 係攸0·01微米至1 〇微米。在另一實施例中，該锻層的表 面可以形成紋理或成形或圖案蝕刻，以增加表面面積、提 呵光卒取率及規劃光離開各層的出光方向。該鍍層可以直 接形成在一發光元件的主要表面或多層表面上，及可形成 在一電極圖案接觸層（contact electr〇de pattern)上。在另一 貫施例中，該鍍層係由多於一層的多層鍍層組成，係經設 计具備特殊光學功能，例如提高或阻擋特定波長範圍的光 通過’或當光接近該複合層的外表面時，逐漸減少一複合 層的折射係數。在上述實施例中，該鍍層可包含其它材質， 例如—氧化石夕’以獲得一多層鑛層（multilayerc〇ating)的特 殊光學特性。該鍍層可取代發光元件上的一保護層或亦可 做為一保護層。該鍍層可以是結晶層或非結晶層。 【實施方式】 第一圖係本發明發光元件結構的一實施例截面示意 圖。該發光元件結構1〇〇包括一基底部1〇1、一發光元件 部jio及一金屬氧化物鍍層部12〇。如同在此使用的，基 底部或次支撐部（submount portion)係提供一發光元件部及 金，氧化物部機械性支撐。該基底部可選自下列任一者： 三氧化二鋁(Al2〇3)、矽、碳化矽(SiC)、氮化鎵銦鋁系材料、 金屬、陶瓷及玻璃。這些材料可以是單晶或非單晶。該次 支1部材質的選擇係基於製造的方便性。典型的次支撐部 係4自下列任者·二氧化一紹(A12Q3)、石夕、碳化石夕（SW)、 金屬、陶£、_及玻璃。如同在此使_，發光元件部 係選自下列任-者··發光二極體、發光異質接面（触( eimumg heterojunctions)、發光量子井結構及其它發光固態 元件。如同在此使用的，金屬氧化物部係選自下列任一者1 1303495 金屬氧化物、碳化矽、氮化鎵系材料及具備適合的光學及 製造特性的其它材料，例如二氧化矽。如同在此使用的， 較佳地丄金屬氧化物鍍層部具有約2.〇或更高的折射係數 及相當南的光穿透率。該鍍層的厚度可以從大約毫微米 (nm)至大於1〇微米，係視元件的需求而定。較佳地，該鍍 層的消光係數(light extinction coefficient)(折射係數的複數 部份）(the complex porti〇n 〇f the index of refracti〇n)係大约 〇=或更小，較佳係αι或更小。較佳地，金屬氧化物部係 运自下列任一者·五氧化二錕(Nb2〇5)、二氧化鈦、五氧化 二鈕(TkO5)、碳化矽及氮化鎵。金屬氧化物鍍層亦可具有 介電特性。介電層（dielectric layer)此一用語在此可交換使 用。 光在一特定材料内的傳播特性係由該材料的複數的 折射係數（the material，s compiex index 〇f refracti〇n)所決 定，如下面式子（2)所示： " n* = η - iK (2)。 在此，n係折射係數，表示在真空中相對光速的相位速 度，k係消光係數或光學損失因子，表示當電磁波通過該材 料時光吸收損失量。η及k皆與輻射波長有關，可輕易獲得 不同材料的這些值。在本發明的一較佳實施例中，該金屬 氧化物鍍層的η值係接近或大於氮化鎵的^值約2· 45。折 射係數的相近可確保來自氮化鎵層的發光通過金屬氧化物 鍍層時，產生非常少的反射光。k值係一吸收測量值，庵兮 儘可能地小。 ~ 當介電層的折射係數η稍微小於一半導體層的折射係 數時，來自該半導體層的入射光其產生内部反射的臨界角 將會非常大。結果是來自氮化鎵發光二極體元件而入射於 1303495 一介電層的大部份光將會通過進入該介電層。該介電層材 料的例子有五氧化二鈮(Nb2〇5)、二氡化鈦(Ti〇2)及五氧化二 鈕(Ta2〇5)。這些介電材料的折射係數相較於氮化錁的折射 係數接近2.4，係分別接近2.39、2.46及2.08。可使用減:鍍 (sputtering)、反應性濺鍍(reactive sputtering)、離子束濺鍍 (ion-beam assisted sputtering)、電子束濺度（e-beam sputtering) 或離子沈積方法（ion-assisted evaporation)、電子束沈積 (e-beam evaporation)方法輕易形成這些介電鍍層。其它的沈 積技術例如化學氣相沈積、電漿化學氣相沈積 (plasma-enhanced chemical vapor deposition)、有機金屬氣相 沈積（metal organic chemical vapor deposition)、原子層沈積 (atomic layer deposition)及熟悉該項技術領域者已知的其它 技術均包含在均等的實施例中。 較it介電鍍層的另一個優點係其可沈積相當厚度並具 有極低的光學損失。一層介電鑛層的厚度可以相當於多層 半‘肢層的厚度，接近3至4微米。厚度大小僅受限於沈 積k間及這些沈積層累積的應力。因為介電層可以做得 厚’其可以被圖案蝕刻而具有幾微米大小的紋理或幾何形 狀。由於較大的結構無法形成，相較於紋理化的半導體層， 上述作法會較有利。此外，半導體層亦擁有昂貴的製造費 用。再者，在介電鍍層上形成紋理或幾何形狀可提供更多 的發光面積，而增加光萃取率。該介電鍍層可以輕易地圖 案蝕刻形成透鏡或其它特定的形狀，以使光萃取率最大化 或使光朝特定方向反射。 w %鑛層可以結合紋理化的半導體表面。再者，當半 ‘月豆主動層或蓋層與介電層之間有良好的折射係數匹配 時，半導體層表面可以是平滑非紋理化，而介電鍍層的外 11 1303495 表面可以紋理化或經圖案蝕刻。此一作法係有利的，因為 如此二來可以加工平滑的晶圓，使得製造費用降低。 第二圖係本發明另一實施例的發光元件結構截面示意 圖。發光結構200包括一底部反射器23〇形成於一透光基 底102例如藍寶石或碳化矽下方表面、一或多層N型層 280、一或多層p型層27〇，及選擇性加入其它中間層（未示 出）、一透光接觸層260例如氧化銦錫(IT〇)、一 N型接觸層 250、一 p型接觸層24〇及一金屬氧化物鍍層12〇。該一或 多層N型層280、一或多層p型層27〇及選擇地其它中間 層（未示出）係包含一發光二極體結構的一主動區域。其它的 發光二極體結構可以是一簡單的pn接面二極體或雙異質接 面結構(double heterojunction structure)或多重量子井結構或 熟悉此技藝者熟知的其它結構。氮化鎵銦鋁系發光二極體 元件中發光部的一個實施例係包含一緩衝層、一或多層第 一蓋層其中至少一層具第一導電性、一主動區包含一或多 層、一或多層第二蓋層其中至少一層具第二導電性、一或 多層接觸層及一或多層電極層。例如，發光部的一個實施 例包含一氮化鎵銦核子（nucleation)層及/或緩衝層、接著是 氮化鎵及/或N型氮化鎵蓋層、接著是一主動區域係包含氮 化鎵銦系多重量子井主動層及N型氮化鎵阻障層、接著是p 型氮化鎵鋁蓋層、接著是N型氮化鎵及/或氮化鎵銦蓋層、 接著是一或多層電極層。電極層的材質可以是銘、鈦/铭、 鉻/铭、鎳/金、鎳/把、鎳/i自或其它已知的組合。主動區域 的各種描述係同樣應用至後面的主動區域350、450、550、 650及750。在第二圖的實施例中，底部反射器230可以是 I呂、銀或多重反射層，以將發射光反射回到發光二極體結 構内部並復奪光的利用性。透光接觸層260可以是氧化銦 12 1303495 錫，此外，透光接觸層可以是鎳/金組合物或其它具有高透 光性的合金。 ° 第三圖係本發明另一實施例的發光元件結構戴面示音、 圖’其具有金屬氧化物鑛層120形成於一透光金屬声261 上，該透光金屬層261已經被紋理化（textured)或链化 (roughened)。透光基底i 03可以是藍賓石或碳化砂。糙化的 透光金屬層提供額外的入射角以使光進入或離開。結合具 預定折射係數的金屬氧化物鍍層120，可增加光萃取率。 第四圖係本發明另一實施例的發光元件結構截面示意 ❿ 圖，其具有一反射層410形成於提供機械性支撐的基底上二 在此一實施例中，發光元件部450係包含至少—或多層N 型層280、一或多層p型層270,及選擇性地其它中間層（未 示出）係製做在另一基底上，再被移開並貼附在基底1〇4 " 上。基底可包含一或多層，例如反射層41〇及導電層 . 262。選擇性地，反射層410、導電層262、金屬線420及 421以及金屬氧化物鍍層120在與原來的基底分離之前可先 形成在發光元件部450上。 將一發光元件部從其原來的基底部分離的一種技術係 修 稱做雷射剝離(laser liftoff)。此一技術係描述於美國專利第 6,071，795 號及山德士 ·τ 等人（SandsT.etal·)於 2005 年 11 月18日發表的從藍寶石基底分離氮化鎵的雷射剝離方法 (Laser Liftoff of Gallium Nitride from Sapphire Substrates)(http://www.ucop.edu/research/micro/98 99/98 13 3:威)。另一種雷射剝離技術的描述係見於安巴格· 0等人 (Ambacher，0·，et aL)發表的”大型氮化鎵基底的雷射剝離及 雷射圖案 I虫刻方法 ”(Laser Liftoff and Laser Patterning of Large Free-standing GaN Substrates)(Mat.Res.Soc.Symp·， 13 1303495 ν〇1·617, ◎ 2000 Materials Research Society)。此三篇文獻係藉由 上述參考内容涵括其全文於本文中。 第五圖係本發明另一實施例的發光元件結構截面示意 圖，其相似於第四圖。一反射器結構411係形成於位於基底 105上的圖案蝕刻的金屬氧化物鍍層121上。如前述實施 例’係使用雷射剝離(laser liftoff)技術將主動發光區550轉 移至基底結構105。基底結構1〇5可包含一或多層例如反射 杰411及金屬氧化物鑛層121。發光元件部450在與原來的 基底分離之前或與具有反射器411及鍍層121的基底1〇5 結合之後，可選擇性地將導電性層262及金屬氧化物鍍層 120形成於發光元件部450上。在基底1〇5上的圖案蝕刻的 金屬氧化物鐘層121上方的反射器結構411可具有各種構形 及形狀，但本發明僅顯示其中一個例子。對於絕緣層上有 秒日日圓製程（silicon on insulator wafer process)技術熟悉的業 者係熟知將主動層轉移至另一基底的其它作法。 第六圖係本發明另一實施例具有覆晶（flip-chip)結構設 計的發光元件結構截面示意圖。發光元件6〇〇包括金屬氧 化物鑛層部622、透光基底106例如藍寶石、主動區域650、 N型接觸層651、P型接觸層641及次支撐基底601。N型 接觸層651、P型接觸層641及次支撐基底601係具有機械 性接觸及電性連通。次支撐基底601具有電路(未示出）以電 性連接於外部電路或構裝結構。次支撐基底601可選擇性 包含其它層例如反射器411及金屬氧化物鍍層121以促進光 反射穿過層452及106,同時與接觸層651及641保持機械 性接觸及電性連接。 第七圖係本發明具一次支撐基底701之覆晶結構設計 之發光元件結構截面示意圖，其中原來的基底已經移除。 14 1303495 發光元件700包括金屬氧化物部722、主動區域75〇、n刑 接觸層751、P型接觸層741及次支撐基底7〇1。N型接^ 層75卜Ρ型接觸層741及次支撐基底7〇1係機械性^觸及 電性連通。次支撐基底701具有電路(未示出）以電性連接於 外部電路或構裝結構。選擇性地，次支撐基底7〇1可包含 其它層例如反射層411及金屬氧化物鍍層121以增進光反射 穿過主動層750,同時與接觸層751及741保持機械性接觸 及電性連接。 第八Α圖至第八D圖係金屬氧化物鍍層之各種圖案及 形狀設計的截面示意圖。金屬氧化物鐘層801、802、803 及804的圖案及形狀係選自下列任一者··肋條狀(ribs)、圓 柱狀、凹槽狀、多邊形肋條狀(polygon shaped ribs)、三角形 脊狀(triangular shaped ridges)、半球形丘陵狀(hemispherical shaped mounds)、平行圓柱狀肋條、橢圓狀、半球形狀 (hemispheres)、直線渠溝或矩形實體狀（rectilinear trenches or solids)、圓錐狀（cones)、有角度圓柱狀(angled cylinders)、 有角度半球形狀（angled hemispheres)、有角度橢圓形狀 (angled ellipsolids)、有角度直線渠溝或矩形實體狀(angled rectilinear trenches or solids)，以及有角度圓錐狀（angled cones)。第九圖係金屬氧化物鍍層之圖案及形狀設計的另一 實施例截面示意圖，其中該金屬氧化物鍍層同時具備光子 晶格(photonic crystal lattice) 901的功能。第八圖及第九圖 並未示出基底或次支撐基底。金屬氧化物鍍層801、802 ' 803、804及901的圖案及形狀設計具有幾何形狀元件係選 自下列任一者：圓柱形、橢圓形、半球形、直線渠溝或矩 形實體狀(rectilinear trenches or solids)、圓錐形、有角度圓 柱形、有角度半球形、有角度橢圓形、有角度直線渠溝或 15 1303495 矩形實體狀’以及有角度圓錐形，並且其中每一幾何形狀 元件之間可呈規則或不規則間隔。在另一些實施例中，金 屬氧化物鑛層可包含-或多層不同組成的金屬氧化物鎮 層，俾使該-或多層間形成不同的折射係數。可加入金屬 氧化物鍍層的非化學計量組成（n〇n_st〇ichi〇metrk composition)，以改變折射係數及消光係數。在本發明實施 例中，係採用多層結構，與其它層一體成形的二氧化矽層 可提高額外的透光性或進而無需採用多層鍍層。視需求而 定，圖案尺寸大小（featureSiZes〇fpatterns)及光子晶格形狀 可從大約50毫微米（nm)至大於幾微米。 上述實施例係用以舉例說明本發明内容，但並非用以 限制本發明範圍，本發明亦包含上述實施例之均等作法。 其它可選擇的技術及製程對於熟悉積體電路及微電子機械 系統(Micro electro mechanical system)(MEMS)技術領域技 術者係屬顯而易知。就上述教示内容觀之，各種變化作法 及貫施例係屬可能。本發明範圍不受限於本發明之詳細說 明’而以後附之申請專利範圍為準。 16 1303495 【圖式簡單說明】 第一圖至第七圖係本發明發光元件結構各種實施例 的截面示意圖。 第八A圖至第八d圖係本發明金屬氧化物鍍層的各 種幾何形狀截面示意圖。 第九圖係本發明具光子晶格圖案之金屬氧化物鍍層1303495 IX. Description of the Invention: [Technical Field to Which the Invention Is Ascribed] The present invention relates to a light wheel element which is used to form components to enhance them; in particular, regarding a rate of occurrence. A new [prior art] A luminescent, diode element is an important solid bear component that converts electrical energy into light. It typically has a semiconductor active layer sandwiched between other layers. As the quality of the conductor material increases, the luminous efficiency of the LED component also increases. Commercially available light-emitting diodes are formed of an alloy of indium, indium, gallium and nitrogen (AlInGaN). These alloys make it possible for the light-emitting diodes & in the ultraviolet to green spectral region. However, the luminous efficiency of the light-emitting diode element is limited by the fact that it cannot couple all of the light generated by the active layer of the light-emitting diode wafer. When a light-emitting diode element is energized by energy, its active layer will illuminate in all directions and reach the surface of the light-emitting element at a number of different angles. A typical semiconductor material has a higher refractive index than air (η^·〇) or epoxy coating (η4·5). According to Snell's law, light passes through a material with a refractive index of ~ when passing through a material incident on a lower refractive index h, when the incident angle is less than a critical angle with respect to the incident plane, the light will pass through. The material of lower refractive index, where 0c = sin Wns) (1). When the angle of incidence of light reaching the surface of the semiconductor is greater, internal total reflection occurs. Light is reflected back into the interior of the light-emitting diode wafer and may be absorbed within the light-emitting diode wafer or metal contact layer attached to the wafer. For conventional light-emitting diode elements, most of the light generated inside the structure is subject to internal total reflection before leaving the semiconductor wafer. For example, a conventional sapphire-based gallium nitride light-emitting diode element, 70% of the 1303495 emission light system is bound between the sapphire substrate and the outer surface of the gallium nitride. This emitted light is repeatedly reflected, which greatly enhances the chance of being reabsorbed and lost. There have been some techniques proposed to improve the light extraction of light-emitting diode elements. An example of providing a light-emitting diode element having a reflective contact layer is provided. Since light trapped inside the structure and incident on the metal contact layer is reflected back inside the element instead of being absorbed, the luminous efficiency of the light-emitting diode element can be improved. This phenomenon also gives the light another opportunity to escape the light-emitting diode wafer the next time it is incident on the surface of the light-emitting diode element. Although the reflective contact layer increases the light extraction rate, conventional light-emitting diode elements still have severe light loss. The top surface of the bismuth is another technique for improving the light extraction rate. R0Ughening scatters cause the reflected light to reflect at any angle, causing the bound light to change its optical path. Light re-reflection can also be prevented by a parallel interface. Part of the scattered light is thus incident on a surface at an angle of incidence that is less than the critical angle of internal total reflection before being absorbed. Typical semiconductor layers are in the form of a film, so only a small size chaining is possible. Furthermore, the 'roughening surface' causes other problems in the process of the light-emitting diode element. For example, touching a seamed surface is a problem. Furthermore, roughening the surface can make it difficult for the reticle to align the wafer. The roughened surface makes pattern recognition equipment used to solder and inspect wafers difficult to work properly. Therefore, another technique that can change the beam path of the bound light becomes a requirement. Another technique for scattering the bound light is to provide a chained interface between the gallium nitride and the underlying substrate, which can be accomplished by pattern etching and roughening the substrate prior to growth into the semiconductor layer. The above technique can effectively increase the light extraction rate. However, the textured surface of the base fare affects the growth of subsequent semiconductor layers. The quality of these semiconductor layers is often adversely affected, and the growth reproducibility is also deteriorated. Other methods for increasing the light output rate are disclosed in U.S. Patent No. 1,034,495, 6,657, 236, 5, the entire disclosure of which is incorporated herein by reference. U.S. Patent No. 6,657,236 and U.S. Patent No. 6,821,804 teach another method of using a first diffusion layer formed of an N-type indium gallium nitride material and a first diffusion layer. The second diffusion layer is preferably a thin layer of light transmissive metal, such as ruthenium, platinum, palladium, palladium/gold, nickel/gold, nickel oxide/gold or the like, preferably deposited on p-type gallium nitride. Indium on the surface. The structure of the light extraction element can be designed as an array of light extraction elements or as multiple disperser layers. The light extraction element may be formed of a material having a refractive index higher than a refractive index of the component coating material. U.S. Patent No. 6,831,302 teaches a structure comprising a multilayered shell layer, a reflective layer that reflects at least about fifty percent of incident light, and a surface of an N-type dopant material, such as The surface of n-type gallium nitride, • has a dielectric function that varies spatially with a certain pattern. U.S. Patent Application Serial No. 2005/0227379 teaches the use of a laser to shape a semiconductor layer to enhance the light extraction rate. Further, the substrate may contain a three-dimensional light extraction geometric pattern, or a light-emitting element I formed on the substrate may contain at least one pattern layer to produce light extraction characteristics. All known techniques do not only slightly improve the efficiency of light extraction, or are expensive to manufacture, or both. Therefore, it is urgent to propose a simple solution which can improve the luminous intensity of the illuminating element and is inexpensive to manufacture. SUMMARY OF THE INVENTION An object of the present invention is to provide an element structure which is inexpensive and has improved light extraction efficiency. Contrary to conventional techniques, the main semiconductor portion of the illuminating element is not altered, so that all current illuminating diodes or other illuminating element structures can take advantage of the present invention. By providing a medium, such as the same plating layer, the present invention can increase the light draw rate of the light-emitting diode element, and light can easily enter and pass through the medium and produce minimal light loss. The surface of the media can be designed to facilitate light exiting the component 1303495 gas or: a cladding layer. Further, the present invention greatly increases the surface area of the element to enhance the light extraction rate. The present invention provides that the medium, such as the refractive index and the extinction coefficient (Hght extmctHHi CGeffieiene), are both formed on the surface of the solid-state light-emitting element or more than the refractive index of the layer of the solid-state light-emitting layer. Or larger than the light-emitting surface, only the smallest Fransnel reflection edge ctions is generated at the interface of the light-emitting surface/dielectric plated layer. Furthermore, the light enters the critical angle of the dielectric county to be close to ninety degrees. A relatively high ratio of luminescence of the layer can enter the dielectric layer. When the dielectric layer has a low loss of material, the light can penetrate the layer without any loss of light. Furthermore, the dielectric layer is roughened. Or appropriately patterning the side 'lighting area can be improved. Compared to many semiconductor layers, the dielectric recording layer can be made thicker' and thus compared with the conventional pattern on the semiconductor, the dielectric layer The larger size of the image can be formed. As a result, the photon has more chance to impinge on the light extraction surface instead of being reflected back into the semiconductor layer or the metal layer which is degraded by light. The material with a larger refractive index than gallium nitride An example of Smc〇n carbide, which can be deposited by plasma_enhanced chemical vapor deposition. In one embodiment, the dielectric medium is formed on a top layer of a light-emitting element to enhance the element. Light extraction rate. The coating has low optical loss and a refractive index of about 2 or more, preferably having a refractive index close to or greater than that of the semiconductor top layer, such as gallium nitride indium aluminum material system. Any material or combination of metal oxide groups: Group II (Ta2〇5), Erbium Oxide (Nb2〇5), Titanium Dioxide (Ti〇2). Other materials are also feasible, such as carbonization. Silicon carbide and GaN based solid solutions. The thickness of the layer is 1303495 攸0·01 micron to 1 〇 micron. In another embodiment, the surface of the wrought layer A texture or a shape or pattern etch can be formed to increase the surface area, enhance the light draw rate, and plan the light exiting the layers. The plating can be formed directly on the major surface or layers of a light-emitting element. On the surface, and can be formed on an electrode pattern contact layer. In another embodiment, the plating layer is composed of more than one layer of multi-layer plating, which is designed to have special optical functions, such as Increasing or blocking light of a specific wavelength range by 'or decreasing the refractive index of a composite layer as the light approaches the outer surface of the composite layer. In the above embodiments, the plating layer may include other materials, such as - oxidized stone eve' A special optical property of a multilayer layer is obtained. The plating layer may replace a protective layer on the light-emitting element or may also serve as a protective layer. The plating layer may be a crystalline layer or an amorphous layer. [Embodiment] The first figure is a schematic cross-sectional view showing an embodiment of a structure of a light-emitting element of the present invention. The light-emitting element structure 1A includes a base portion 〇1, a light-emitting element portion jio, and a metal oxide plating portion 12A. As used herein, the base or submount portion provides a light-emitting element portion and gold, and the oxide portion is mechanically supported. The base portion may be selected from the group consisting of: aluminum oxide (Al2〇3), tantalum, tantalum carbide (SiC), gallium indium nitride-based material, metal, ceramic, and glass. These materials may be single crystal or non-single crystal. The selection of the material of the second branch is based on the convenience of manufacture. A typical secondary support system is from the following ones: A12Q3, AX, Shihua, SW, Metal, Tao, and Glass. As used herein, the light-emitting element portion is selected from the group consisting of: a light-emitting diode, an eimumg heterojunctions, a light-emitting quantum well structure, and other light-emitting solid elements. As used herein, The metal oxide portion is selected from the group consisting of 1 1303495 metal oxide, tantalum carbide, gallium nitride based materials, and other materials having suitable optical and manufacturing properties, such as ruthenium dioxide. As used herein, preferably. The mantle metal oxide plating portion has a refractive index of about 2. 〇 or higher and a relatively south light transmittance. The thickness of the plating layer may range from about nanometers (nm) to more than 1 〇 micrometer, depending on the component requirements. Preferably, the light extinction coefficient (the complex porti〇n 〇f the index of refracti〇n) of the coating is about 〇= or less, preferably Preferably, the metal oxide portion is transported from any of the following: bismuth pentoxide (Nb2〇5), titanium dioxide, pentoxide oxide (TkO5), tantalum carbide and gallium nitride. The oxide coating may also have Dielectric property. The term "dielectric layer" is used interchangeably herein. The propagation characteristic of light in a particular material is the refractive index of the complex material of the material (the material, s compiex index 〇f refracti〇n Determined as shown in the following equation (2): " n* = η - iK (2) Here, the n-type refractive index indicates the phase velocity relative to the speed of light in vacuum, k-based extinction coefficient or optics The loss factor represents the amount of light absorption loss when the electromagnetic wave passes through the material. Both η and k are related to the wavelength of the radiation, and these values of different materials can be easily obtained. In a preferred embodiment of the invention, the metal oxide coating is η. The value is close to or greater than the value of gallium nitride of about 2.45. The closeness of the refractive index ensures that when the luminescence from the gallium nitride layer passes through the metal oxide coating, very little reflected light is produced. The k value is an absorption measurement. , 庵兮 is as small as possible. ~ When the refractive index η of the dielectric layer is slightly smaller than the refractive index of a semiconductor layer, the critical angle at which the incident light from the semiconductor layer produces internal reflection will be very large. Most of the light from a gallium nitride light-emitting diode element incident on a dielectric layer of 1303495 will pass through the dielectric layer. An example of the dielectric layer material is tantalum pentoxide (Nb2〇5). Titanium dihydride (Ti〇2) and Ni2O2 (Ta2〇5). The refractive index of these dielectric materials is close to 2.4 compared to that of tantalum nitride, which is close to 2.39, 2.46 and 2.08, respectively. Reduction: sputtering, reactive sputtering, ion-beam assisted sputtering, e-beam sputtering or ion-assisted evaporation, electrons These dielectric plating layers are easily formed by an e-beam evaporation method. Other deposition techniques such as chemical vapor deposition, plasma-enhanced chemical vapor deposition, metal organic chemical vapor deposition, atomic layer deposition, and familiarity with the Other techniques known to those skilled in the art are included in the equivalent embodiments. Another advantage over the electroless plating layer is that it can deposit a considerable thickness and has an extremely low optical loss. The thickness of a layer of dielectric ore can be equivalent to the thickness of a multilayer semi-layer of limbs, approaching 3 to 4 microns. The thickness is limited only by the deposition k and the stresses accumulated by these deposits. Because the dielectric layer can be made thicker, it can be patterned to have a texture or geometry of a few microns in size. Since a larger structure cannot be formed, the above method is advantageous as compared with a textured semiconductor layer. In addition, the semiconductor layer also has an expensive manufacturing cost. Furthermore, the formation of texture or geometry on the dielectric plating layer provides more luminescent area and increases the light extraction rate. The dielectric layer can be easily patterned to form a lens or other specific shape to maximize light extraction or reflect light in a particular direction. The w% mineral layer can be combined with a textured semiconductor surface. Furthermore, when there is a good refractive index matching between the semi-moon bean active layer or the cap layer and the dielectric layer, the surface of the semiconductor layer may be smooth and non-textured, and the outer surface of the dielectric layer may be textured or Pattern etched. This approach is advantageous because, as a result, smooth wafers can be processed, resulting in reduced manufacturing costs. The second drawing is a schematic sectional view showing the structure of a light-emitting element of another embodiment of the present invention. The light emitting structure 200 includes a bottom reflector 23 formed on a transparent substrate 102 such as a sapphire or tantalum carbide surface, one or more N-type layers 280, one or more p-type layers 27, and optionally added to other intermediate layers ( Not shown), a light transmissive contact layer 260 such as indium tin oxide (IT〇), an N-type contact layer 250, a p-type contact layer 24A, and a metal oxide plating layer 12A. The one or more multi-layer N-type layers 280, one or more p-type layers 27, and optionally other intermediate layers (not shown) comprise an active region of a light-emitting diode structure. Other light emitting diode structures can be a simple pn junction diode or double heterojunction structure or multiple quantum well structure or other structures well known to those skilled in the art. An embodiment of the light-emitting portion of the gallium nitride indium-aluminum-based light-emitting diode device includes a buffer layer, one or more layers of the first cap layer, wherein at least one layer has a first conductivity, and an active region includes one or more layers, or At least one of the plurality of second cover layers has a second conductivity, one or more contact layers, and one or more electrode layers. For example, an embodiment of the light emitting portion includes a gallium nitride indium nucleation layer and/or a buffer layer, followed by a gallium nitride and/or N-type gallium nitride cap layer, followed by an active region containing nitriding A gallium-indium multiple quantum well active layer and an N-type gallium nitride barrier layer, followed by a p-type gallium nitride aluminum cap layer, followed by an N-type gallium nitride and/or a gallium nitride indium cap layer, followed by an Multilayer electrode layer. The material of the electrode layer may be Ming, Titanium/Ming, Chromium/Ming, Nickel/Gold, Nickel/Press, Nickel/i or other known combinations. The various descriptions of the active area are also applied to the subsequent active areas 350, 450, 550, 650, and 750. In the embodiment of the second figure, the bottom reflector 230 may be a illuminate, silver or multiple reflective layer to reflect the emitted light back into the interior of the luminescent diode structure and to regain light utilization. The light transmissive contact layer 260 may be indium oxide 12 1303495 tin. Further, the light transmissive contact layer may be a nickel/gold composition or other alloy having high light transmittance. The third figure is a light-emitting element structure according to another embodiment of the present invention, and has a metal oxide ore layer 120 formed on a light-transmitting metal sound 261, which has been textured. (textured) or roughened. The light-transmitting substrate i 03 may be lansite or carbonized sand. The roughened light transmissive metal layer provides an additional angle of incidence to allow light to enter or exit. In combination with the metal oxide plating layer 120 having a predetermined refractive index, the light extraction rate can be increased. Figure 4 is a cross-sectional view showing a structure of a light-emitting element according to another embodiment of the present invention, having a reflective layer 410 formed on a substrate for providing mechanical support. In this embodiment, the light-emitting element portion 450 includes at least - Or a plurality of layers of N-type layer 280, one or more layers of p-type layer 270, and optionally other intermediate layers (not shown) are fabricated on another substrate, removed and attached to substrate 1〇4 " on. The substrate may comprise one or more layers, such as a reflective layer 41 and a conductive layer. Alternatively, the reflective layer 410, the conductive layer 262, the metal lines 420 and 421, and the metal oxide plating layer 120 may be formed on the light-emitting element portion 450 before being separated from the original substrate. One technique for separating a light-emitting element portion from its original base portion is referred to as a laser liftoff. This technique is described in U.S. Patent No. 6,071,795 and by Sands T. et al., published on November 18, 2005, a laser stripping method for separating gallium nitride from a sapphire substrate (Laser) Liftoff of Gallium Nitride from Sapphire Substrates) (http://www.ucop.edu/research/micro/98 99/98 13 3: Wei). Another description of the laser stripping technique is found in the "Laser Liftoff of the Large Gallium Nitride Substrate Laser Peeling and Laser Pattern I" by Ambacher et al. (Ambacher, 0., et aL). And Laser Patterning of Large Free-standing GaN Substrates) (Mat. Res. Soc. Symp., 13 1303495 ν〇1·617, ◎ 2000 Materials Research Society). The three documents are hereby incorporated by reference in their entirety. Fig. 5 is a schematic sectional view showing the structure of a light-emitting element of another embodiment of the present invention, which is similar to the fourth figure. A reflector structure 411 is formed on the patterned etched metal oxide layer 121 on the substrate 105. The active light-emitting region 550 is transferred to the base structure 105 as in the foregoing embodiment using a laser liftoff technique. The base structure 1〇5 may comprise one or more layers such as a reflective 411 and a metal oxide ore layer 121. The light-emitting element portion 450 can selectively form the conductive layer 262 and the metal oxide plating layer 120 on the light-emitting element portion 450 before being separated from the original substrate or after being bonded to the substrate 1〇5 having the reflector 411 and the plating layer 121. . The reflector structure 411 over the pattern etched metal oxide clock layer 121 on the substrate 1 可 5 can have various configurations and shapes, but the present invention shows only one example. Other practices familiar to those skilled in the art of silicon on insulator wafer process are well known to transfer the active layer to another substrate. Fig. 6 is a schematic cross-sectional view showing the structure of a light-emitting element having a flip-chip structure design according to another embodiment of the present invention. The light-emitting element 6A includes a metal oxide ore layer portion 622, a light-transmitting substrate 106 such as sapphire, an active region 650, an N-type contact layer 651, a P-type contact layer 641, and a sub-support substrate 601. The N-type contact layer 651, the P-type contact layer 641, and the sub-support substrate 601 have mechanical contact and electrical communication. The sub-support substrate 601 has circuitry (not shown) for electrical connection to an external circuit or structure. The secondary support substrate 601 can optionally include other layers such as reflectors 411 and metal oxide plating 121 to facilitate light reflection through layers 452 and 106 while maintaining mechanical and electrical contact with contact layers 651 and 641. The seventh figure is a schematic cross-sectional view showing the structure of the light-emitting element of the flip-chip structure of the primary support substrate 701 of the present invention, in which the original substrate has been removed. 14 1303495 The light-emitting element 700 includes a metal oxide portion 722, an active region 75A, a n-contact layer 751, a P-type contact layer 741, and a sub-support substrate 7〇1. The N-type contact layer 75 has a mechanical contact and electrical connection with the sub-contact layer 741 and the sub-support substrate 7〇1. The sub-support substrate 701 has circuitry (not shown) for electrical connection to an external circuit or structure. Alternatively, the sub-support substrate 7〇1 may include other layers such as a reflective layer 411 and a metal oxide plating layer 121 to enhance light reflection through the active layer 750 while maintaining mechanical and electrical contact with the contact layers 751 and 741. Figures 8 through 8D are schematic cross-sectional views of various patterns and shape designs of metal oxide coatings. The patterns and shapes of the metal oxide clock layers 801, 802, 803, and 804 are selected from the group consisting of ribs, cylinders, grooves, polygon shaped ribs, and triangular ridges. Triangular shaped ridges, hemispherical shaped mounds, parallel cylindrical ribs, elliptical, hemispheres, rectilinear trenches or solids, cones, Angled cylinders, angled hemispheres, angled ellipsolids, angled rectilinear trenches or solids, and angled conical Angled cones). The ninth drawing is a schematic cross-sectional view showing another embodiment of the pattern and shape design of the metal oxide plating layer, wherein the metal oxide plating layer simultaneously functions as a photonic crystal lattice 901. The eighth and ninth views do not show the substrate or sub-support substrate. The metal oxide coatings 801, 802' 803, 804, and 901 are patterned and shaped to have geometrical elements selected from one of the following: cylindrical, elliptical, hemispherical, straight trench, or rectangular solid (rectilinear trenches or Solids), conical, angular cylindrical, angled hemispherical, angular elliptical, angled straight groove or 15 1303495 rectangular solid shape and angled conical, and each geometric element can be present Rule or irregular interval. In other embodiments, the metal oxide ore layer may comprise - or a plurality of layers of metal oxide layers of different compositions such that the layers or layers form different refractive indices. A non-stoichiometric composition of the metal oxide coating (n〇n_st〇ichi〇metrk composition) may be added to change the refractive index and the extinction coefficient. In the embodiment of the present invention, a multi-layered structure is used, and the ceria layer integrally formed with other layers can increase the light transmittance or thereby eliminate the need for a multi-layer plating. Depending on the requirements, the feature size (featureSiZes 〇 fpatterns) and the photonic lattice shape may range from about 50 nanometers (nm) to more than a few microns. The above embodiments are intended to be illustrative of the present invention, but are not intended to limit the scope of the invention, and the invention also includes the equivalents of the embodiments described above. Other alternative techniques and processes are readily apparent to those skilled in the art of integrated circuit and micro electro mechanical system (MEMS) technology. As far as the above teachings are concerned, various changes and practices are possible. The scope of the present invention is not limited by the details of the invention, and the scope of the appended claims will be limited. 16 1303495 BRIEF DESCRIPTION OF THE DRAWINGS The first to seventh drawings are schematic cross-sectional views showing various embodiments of the light-emitting element structure of the present invention. Figs. 8A to 8D are schematic cross-sectional views showing various geometrical shapes of the metal oxide plating layer of the present invention. The ninth figure is a metal oxide coating of the present invention with a photonic lattice pattern
之一實施例的截面示意圖。 主要部份之代表符號： 100-…發光元件結構 101…-基底部 102, 103, 106----透光基底 104，105…-基底 120, 121-…金屬氧化物鍍層 200—發光結構 230-…底部反射器 240—P型接觸層 250-…N型接觸層 260—透光接觸層 261—透光金屬層 262—導電性層 270-…P型層 280-…N型層 410—反射層 411…-反射器 420, 421-…金屬線 450—發光元件部 550-…發光元件部 600…-發光元件 601-…次支撐基底 622—金屬氧化物鑛層部 641-…P型接觸層 650-…主動區域 651-…N型接觸層 700—發光元件 701-…次支撐基底 722—金屬氧化物部 741…-P型接觸層 750—主動區域 751…-N型接觸層 801，802,803,804——金屬氧化物鍍層 901-…光子晶格層 17A schematic cross-sectional view of one embodiment. Representative symbols of the main parts: 100-...light-emitting element structure 101...-substrate part 102, 103, 106----transparent substrate 104, 105...-substrate 120, 121-...metal oxide plating layer 200-light emitting structure 230 -... bottom reflector 240 - P type contact layer 250 - ... N type contact layer 260 - light transmissive contact layer 261 - light transmissive metal layer 262 - conductive layer 270 - ... P type layer 280 - ... N type layer 410 - reflection Layer 411...-reflector 420, 421-...metal wire 450-light-emitting element portion 550-...light-emitting element portion 600...-light-emitting element 601-...sub-support substrate 622-metal oxide ore layer portion 641-...P-type contact layer 650-...active region 651-...N-type contact layer 700-light-emitting element 701-...sub-support substrate 722-metal oxide portion 741...-P-type contact layer 750-active region 751...-N-type contact layer 801,802,803,804- —metal oxide plating 901-...photonic lattice layer 17