1249866 九、發明說明： 【發明所屬之技術領域】 本發明是有關氮化鎵系多重量子井發光二極體，特別是有關氣化蘇系 多重量子井發光二極體中，低電阻11型接觸層的結構。 【先前技術】 氮化鎵(GaN)系發％二極體，由於可以藉著控制材料的組成來達到所需 的能隙(Band Gap)，因此可以製作出各種色光、尤其是需要高能隙的藍光或 务、光發光-極體。氮化鎵系發光二極體的相關技術因此成為業界積極研發 的重點。 -種習知的氮化«發光二極體，其發光層主要是以氮化鎵以及氮化 銦鎵(InxG心N，牧卬為位井(Potemial WeU)的多重量子井1249866 IX. Description of the invention: [Technical field of the invention] The present invention relates to a gallium nitride-based multiple quantum well light-emitting diode, in particular to a gas-supplemented multi-quantum well light-emitting diode, a low-resistance type 11 contact The structure of the layer. [Prior Art] Gallium Nitride (GaN) is a % diode. Since the required energy band (Band Gap) can be achieved by controlling the composition of the material, various color lights, especially those requiring high energy gap, can be produced. Blu-ray or light, light-emitting. The related technology of gallium nitride-based light-emitting diodes has thus become a focus of active research and development in the industry. - A well-known nitriding diode, the luminescent layer is mainly a multi-quantum well of gallium nitride and indium gallium nitride (InxG core N, Potemial WeU)
Well，MQW)結構，利用電子與電洞在ΙηΛΐ χΝ(〇如)位井結合而釋放出光 子。在此發光層之下，-般是採用有n型摻雜（例如，石夕）的n型氛化蘇 接觸層。 為使此η型氮化鎵接觸層達到低電阻的要求，一般是採用換雜高濃度 (>lxl〇 cm )的石夕(Si)來製作η型氮化蘇接觸層。但在實際製造過程中發 現，η型氮化雜騎往往會_重摻雜的結果，由於晶格不匹配形成過大 的應力’導致^生龜裂、甚至斷裂的現象。這些現象，不僅影響η型氮化 鎵接觸層賴造品f，還會增加在製程巾下—步驟，在η型氮化嫁接觸層 上方製作n型歐姆接觸電極的困難。這些缺點使得生產出來的氮化蘇系多 重里子井發光—極體’整體電特性變差鱗電不良，甚至成為廢品。影響 所及，故些氮化鎵Μ重量子井發光二極體—方面需要較高的操作電壓， 1249866 另一方面是製造的良率下降，生產成本提 使得運作時雜之電功率增加 r%。 此外，矽重摻雜於 里氮化鎵接觸層的結果，亦容易形成點缺陷(PinWell, MQW) structure, using electrons and holes to combine photons in the ΙηΛΐ χΝ (for example) wells to release photons. Below this luminescent layer, an n-type sulphide contact layer having an n-type doping (e.g., Shi Xi) is generally used. In order to achieve the low resistance requirement of the n-type gallium nitride contact layer, the n-type tantalum-sulphide contact layer is generally formed by replacing the high concentration (>lxl〇 cm) of the stone (Si). However, in the actual manufacturing process, it has been found that the η-type nitriding ride tends to result in _ heavy doping, resulting in excessive cracking due to lattice mismatch, resulting in cracking or even fracture. These phenomena not only affect the n-type gallium nitride contact layer, but also increase the difficulty in fabricating the n-type ohmic contact electrode over the n-type nitride contact layer. These shortcomings make the luminescence of the uranium-series uranium wells, which are produced by the uranium-series, have poor electrical properties and even become waste products. As a result, some GaN gallium weight sub-wells require higher operating voltages. On the other hand, the manufacturing yield is reduced, and the production cost is increased by r%. In addition, the result of heavy doping of the gallium nitride contact layer is also easy to form point defects (Pin
Hole)使件亂化蘇系多重量子井發光二極體整體二極體特性變差，而且在 操作上會有漏電流的產生。 【發明内容】 因此’為了克服上述先前技術的缺陷，本發明提出數種^型氮化蘇接 觸層的結構，以解決前揭問題。 本發明触術思想可藉由第—圖而清楚揭露出來。第—圖細示三族 氮化物材料之晶格常數_iceCo酸nt)與紐。如第一圖所示，㈣（氮 化鎵）的晶格常數％約為318A。由其晶格匹配線上下延伸，可以發現 -具有特定組成的AIxInyGai.x.yN(氮化細鎵，βχ，γ<1，χ+γ幻），擁相同 的晶格常數以及更高魏隙。耻，藉她合兩麵成不_Ν 和 AlpInqGai_p_qN (Ogm，n<1; 0<p，q<1;in+n<1;p+qs 1;m<p)所形成的超晶格 (Superlattice)結構，可以得到高摻雜濃度(>lxl〇19cm·3)且低電阻的n型氮化 鎵接觸層。此外，利用紹、銦、鎵各組成的調配可以得到兩兩晶格常數相 匹配的晶膜，而不會造成在!!型氮化鎵接觸層内因矽重摻雜而龜裂，改善 重摻雜氮化鎵接觸層的品質，且減少！!型歐姆接觸製造的困難，進而會大 大降低整個氮化鎵系多重量子井發光二極體的操作電壓。 茲配合下列圖示、實施例之詳細說明及申請專利範圍，將上述及本發 明之其他目的與優點詳述於後。 1249866 【實施方式】 第二圖係依據本發明第一實施例之氮化鎵系多重量子井發光二極體之 結構示意圖。一習知的氮化鎵系發光二極體的結構，如第二圖所示，_ 般是以C-Plane或R-Plane或A-Plane之氧化鋁單晶（Sapphire)或碳 化石夕(6H-SiC或4H-SiC)為基板10，其他可用於基板的材質還包括 Si、ZnO、GaAs或尖晶石（MgAl2〇4) ’或是晶格常數接近於氮化物 半導體之單晶氧化物。然後，此結構在基板10之一側面包含有_ 緩衝層(buffer layer)20，此緩衝層20係由具有一特定組成的氮化叙蘇鋼 (AlubGaaliibN，〇Sa，b<l，a+b^l)所構成。在此緩衝層2〇之上，此結構 包含有一 η型接觸層(contact layer)30，此η型接觸層30的結構即係本發明 的焦點所在。在此η型接觸層30之上，為一覆蓋部份η型接觸層3〇的表 面的發光層(active layer)42，此發光層42係由氮化銦鎵(inGaN)所構成。另 外，在此發光層同一側、以及在此η型接觸層30表面未被覆蓋的部 份之上，此結構另包含有一負電極40。 在此發光層42之上’此結構依序由下往上堆疊、分別包含一 Ρ型被覆層（cladding layer)50、一 ρ型接觸層60、以及覆蓋部份ρ 型接觸層60表面的正電極70。位於活性發光層上的p型被覆層5〇， 係由有鎂摻雜(Mg-doped)、具有一特定組成的氮化鋁鎵銦（A1 i_e dGaeIndN， 〇Sc，d<l，c+d^l)所構成。位於ρ型被覆層50上的ρ型接觸層6〇，則係 由有鎂摻雜、具有另一特定組成的氮化鋁鎵銦（Al^fGaeliifN，0^e，f<l， e+f$l)所構成。 如第二圖所示，此實施例的η型接觸層30係由多層、有石夕摻雜的氮化 1249866 鎵基層301、以及有矽摻雜的氮化紹鎵基層302交互疊加所構成的超晶格 (Supperlattice)結構，其中有矽摻雜的氮化鋁鎵基層302的能隙要較有石夕推 雜的氮化鎵基層301來的大。更明確的說，11型接觸層30係在一層有石夕換 雜的氮化鎵基層301上、疊加一層有矽摻雜的氮化鋁鎵基層3〇2、其上再疊 加層有石夕換雜的氮化叙基層301、以此類推。或者，n型接觸層係在 層有石夕摻雜的氮化铭叙基層302上、疊加一層有石夕摻雜的氮化鎵基層 301、其上再疊加一層有矽摻雜的氮化铭鎵基層3〇2、以此類推。各氮化録 基層的厚度不必相同，但均在20人〜200 A之間，成長溫度在（500。^ 〜1200 C之間。各氮化鋁鎵(Ail gGagN，〇<g<1)基層的組成(亦即，前列 分子式中的參數g)不必相同、厚度不必相同，但均在2〇人〜2〇〇人之間， 成長溫度亦在600°C〜1200°C之間。n型接觸層30總厚度在2〜5μιη之 間總共包含50〜500層氮化鎵基層3〇1與氮化鋁鎵基層3〇2，其中至少有 一層（不論是氮化鎵基m戈氮化紹鎵基層3〇2)的石夕推雜濃度大於 lxl〇19cm.3。氮化鎵基層3〇1與氮化銘鎵基層3〇2的層數相同或其層數之差 為一。 第三圖係依據本發明第二實施例之氮化鎵系多重量子井發光二極體之 結構不意圖。如第三圖所示，此實施例之結構與第一實施例完全相同，唯 一的差別是在η型接觸層32所採用的材質不同。此實施例的η型接觸層％ 係由多層、抽與石夕共同摻雜的氮化鎵基層奶、以及有銦與石夕共同推雜的 紹鎵基層322又互疊加所構成的超晶格結構，其中有銦财共同換雜 的氮化_基層322的能隙要較有銦與料同摻雜的氮化蘇基層321來的 大更月確的說，η型接觸層32係在一層有銦與石夕共同摻雜的氮化嫁基層 1249866 321上、疊加一層有銦與矽共同摻雜的氮化鋁鎵基層322、其上再疊加一層 有銦與梦共同摻雜的氮化鎵基層321、以此類推。或者，η型接觸層％係 在-層有銦财共同換雜的氮化銘鎵基層322上、疊加—層有姻與石夕共同 摻雜的II化絲層321、其上再疊加—層有銦财制雜的氮化絲基層 322、以此類推。各氮化鎵基層的厚度不必相同，但均在2〇Α〜細入之間， 成長溫度在600。(：〜謂。C之間。各氮化鱗基層的組成不必相同、 厚度不必相同，但均在2从〜2()() Α之間，成長溫度亦在副。c〜i2〇(rc 之間。η型接觸層32總厚度在2〜5μπι之間，總共包含5〇〜5〇〇層氮化鎵基 層切與氮化銘鎵基層似’其中至少有一層（不論是氮化鎵基層切或氮 化紹鎵基層322)的銦卿摻雜濃度大於lxl〇1W3。氮化鎵基層切與氣 化鋁鎵基層322的層數相同或其層數之差為一。 第四圖係依據本發明第三實_之氮化鎵，好重量子井發光二極體之 結構示意圖。如第四圖所示’此實施例之結構與第_、二實施例完全相同， 唯-的差別是在η型接觸層34所採用的材質不同。此實施例的η型接觸層 34係由夕層、有鋼與石夕共同掺雜的氮化銘鎵基層糾、以及有銦與石夕共同 摻雜的氮化銘鎵基層342交互疊加所構成的超晶格結構，其中有銦與石夕共 同摻雜的氮化贿基層342的能隙要較有銦與破共同摻雜的氮化贿基層 34i來的大。更明確的說’ n型接觸層34係在一層有銦與石夕共同掺雜的氮 化紹鎵基層341上、疊加—層有銦與碎共同摻雜的氮化麟基層342、其上 再疊加-層有銦與石夕共同摻雜的氮德鎵基層糾、以此類推。或者，_ 接觸層34係在-層有銦與石夕共同換雜的氮化銘鎵基層拟上、疊加—層有 銦與石夕共轉_氮化輯基層撕、其上再疊加—層有銦财共同捧雜的 1249866 氮化紹鎵基層342、以此類推。各氮她鎵層的厚度不必相同，但均在 20A~200人之間，成長溫度在·。c〜12〇〇〇c之間。相鄰的氮德 鎵基層的組成不㈣、但不相鄰的氮化崎基層驗成可以綱、也可以 不相同，各層厚度不必相同，但均在2〇人〜2〇〇人之間，成長溫度亦在 600°C〜1200°C之間。n型接觸層34總厚度在2〜5μιη之間，總共包含 50〜500層氮化铭鎵基層341與氮化銘鎵基層342，其中至少有一層（不論 是氮化鋁鎵基層341或氮化鋁鎵基層342)的銦與矽摻雜濃度大於 lxl019cm·3。氮化铭鎵基層341與氮化紹鎵基層342的層數相同或其層數之 差為一。 第五圖係依據本發明第四實施例之氮化鎵系多重量子井發光二極體之 結構示意圖。如第五圖所示，此實施例之結構與前述實施例完全相同，唯 的差別疋在η型接觸層36所採用的材質不同。此實施例的n型接觸層％ 係由多層、有矽摻雜的氮化鋁銦鎵基層361、以及有矽摻雜的氮化鋁銦鎵基 層362父互璧加所構成的超晶格結構，其中有石夕摻雜的氮化铭銦鎵基層362 的能隙要較有矽掺雜的氮化鋁銦鎵基層361來的大。更明確的說，n型接觸 層36係在一層有矽摻雜的氮化鋁銦鎵基層361上、疊加一層有石夕掺雜的氮 化铭銦鎵基層362、其上再疊加一層有石夕掺雜的氮化鋁銦鎵基層361、以此 類推。或者，η型接觸層36係在一層有矽摻雜的氮化鋁銦鎵基層362上、 疊加一層有矽摻雜的氮化鋁銦鎵基層361、其上再疊加一層有矽摻雜的氮化 鋁銦鎵基層362、以此類推。各氮化鋁銦鎵基層的厚度不必相同，但均在 20人〜200 Α之間，成長溫度在600°C〜1200°C之間。相鄰的氮化鋁 銦鎵基層的組成不相同、但不相鄰的氮化鋁銦鎵層的組成可以相同、也可 1249866 以不相同，各層厚度不必相同，但均在20人〜200 A之間，成長溫度亦 在600。(：〜1200°C之間。n型接觸層36總厚度在2〜5|^1之間，總共包 含50〜500層氮化鋁銦鎵基層361與氮化鋁銦鎵基層362，其中至少有一声 (不論是氮化鋁銦鎵基層361或氮化鋁銦鎵基層362)的矽摻雜濃度大於 lxl019cm3。氮化紹銦鎵基層361與氮化铭銦鎵基層362的層數相同或其層 數之差為一。 在此貫施例中，藉由組合兩種組成不同的氮化鋁銦鎵AjjnnGhmN和 AlpInqGa!例N (0$m，n<l; 0<p，q<l;m+n<i;p+qg 1;m<p)所形成的超晶格結 構，可以得到高摻雜濃度(>lxl〇19cm-3)且低電阻的n型氮化鎵接觸層。此外， 利用鋁、銦、鎵各組成的調配可以得到兩兩晶格常數相匹配的晶膜，而不 會造成在η型氮化鎵接觸層内因矽重摻雜而龜裂，改善重摻雜氮化鎵接觸 層的品質，且減少η型歐姆接觸製造的困難，進而會大大降低整個氮化鎵 系多重量子井發光二極體的操作電壓。 惟以上所述者，僅為本發明之較佳實施例而已，當不能以此限定本發 明實施之範圍。即大凡依本發明申請專利範圍所作之均等變化與修飾，皆 應仍屬本發明專利涵蓋之範圍内。 【圖式簡單說明】 第一圖係顯示三族氮化物材料之晶格常數(Lattice Constant)與能隙。 第二圖係依據本發明第一實施例之氮化鎵系多重量子井發光二極體之結構 示意圖。 第三圖係依據本發明第二實施例之氮化鎵系多重量子井發光二極體之結構 π 1249866 示意圖。 第四圖係依據本發明第三實施例之氮化鎵系多重量子井發光二極體之結構 示意圖。 第五圖係依據本發明第四實施例之氮化鎵系多重量子井發光二極體之結構 示意圖。 【主要元件符號說明】 10 基板 20 緩衝層 30 η型接觸層 32 η型接觸層 34 η型接觸層 36 η型接觸層 40 負電極 42 發光層 50 ρ型被覆層 60 Ρ型接觸層 70 正電極 301 有矽摻雜的氮化鎵基層 302 有矽摻雜的氮化鋁鎵基層 321 有銦與矽摻雜的氮化鎵基層 322 有銦與矽摻雜的氮化鋁鎵基層Hole) causes the components of the S-series multiple quantum wells to have poor overall diode characteristics, and there is leakage current in operation. SUMMARY OF THE INVENTION Therefore, in order to overcome the deficiencies of the prior art described above, the present invention proposes a structure of several types of nitriding contact layers to solve the above problems. The idea of the touch of the present invention can be clearly revealed by the first figure. The first figure shows the lattice constant of the three kinds of nitride materials _iceCo acid nt) and New Zealand. As shown in the first figure, (4) (gallium nitride) has a lattice constant % of about 318A. By extending its lattice matching line, it can be found that AIxInyGai.x.yN (nitrided fine gallium, βχ, γ<1, χ+γ illusion) with a specific composition, has the same lattice constant and higher Wei gap. . Shame, by her two sides into a superlattice formed by _Ν and AlpInqGai_p_qN (Ogm, n<1;0<p,q<1;in+n<1;p+qs1;m<p) The superlattice structure provides a low-doping concentration (>lxl〇19cm·3) and a low-resistance n-type gallium nitride contact layer. In addition, the use of the composition of the various compositions of Shao, indium and gallium can obtain a crystal film with a matching lattice constant of two or two, without causing cracking due to heavy doping in the GaN contact layer, improving the re-doping. The quality of the GaN contact layer is reduced! The difficulty in manufacturing ohmic contact, which in turn greatly reduces the operating voltage of the entire gallium nitride-based multiple quantum well light-emitting diode. The above and other objects and advantages of the present invention will be described in detail below with reference to the accompanying drawings. 1249866 [Embodiment] The second figure is a schematic structural view of a gallium nitride-based multiple quantum well light-emitting diode according to a first embodiment of the present invention. A conventional structure of a gallium nitride-based light-emitting diode, as shown in the second figure, is generally a C-Plane or R-Plane or A-Plane alumina single crystal (Sapphire) or carbonized stone ( 6H-SiC or 4H-SiC) is the substrate 10, and other materials that can be used for the substrate include Si, ZnO, GaAs or spinel (MgAl2〇4)' or a single crystal oxide whose lattice constant is close to that of the nitride semiconductor. . Then, the structure includes a buffer layer 20 on one side of the substrate 10, and the buffer layer 20 is made of a nitrided steel of a specific composition (AlubGaaliibN, 〇Sa, b<l, a+b) ^l) constitutes. Above this buffer layer 2, this structure comprises an n-type contact layer 30, the structure of which is the focus of the present invention. Above the n-type contact layer 30 is an active layer 42 covering a surface of a portion of the n-type contact layer 3, which is made of indium gallium nitride (InGaN). Further, on the same side of the light-emitting layer, and above the portion where the surface of the n-type contact layer 30 is not covered, the structure further includes a negative electrode 40. On the light-emitting layer 42, the structure is sequentially stacked from bottom to top, and includes a clam coating layer 50, a p-type contact layer 60, and a surface covering the p-type contact layer 60. Electrode 70. The p-type cladding layer 5 on the active light-emitting layer is made of Mg-doped aluminum gallium indium with a specific composition (A1 i_e dGaeIndN, 〇Sc, d<l, c+d ^l) constitutes. The p-type contact layer 6〇 located on the p-type cladding layer 50 is an aluminum gallium indium nitride (Al^fGaeliifN, 0^e, f<l, e+f) doped with magnesium and having another specific composition The composition of $l). As shown in the second figure, the n-type contact layer 30 of this embodiment is composed of a plurality of layers, a NiTi-doped nitridium 1249866 gallium-based layer 301, and an antimony-doped bismuth-doped gallium-based layer 302. A superlattice (Supperlattice) structure in which the energy gap of the germanium-doped aluminum gallium nitride base layer 302 is larger than that of the gallium nitride base layer 301. More specifically, the type 11 contact layer 30 is on a layer of GaN-based layer 301 with a cerium-doped layer, and a layer of ytterbium-doped aluminum-gallium-based layer 3 is stacked thereon. The mixed nitride layer 301, and so on. Alternatively, the n-type contact layer is formed on the layer of the cerium-implanted base layer 302 having a cerium doped layer, and a layer of galvannea-doped GaN-based layer 301 is superposed thereon, and a layer of ytterbium-doped nitriding is superposed thereon. The gallium base layer 3〇2, and so on. The thickness of each nitride substrate is not necessarily the same, but is between 20 and 200 A, and the growth temperature is between 500 and 1200 C. Each aluminum gallium nitride (Ail gGagN, 〇 < g < 1) The composition of the base layer (that is, the parameter g in the precursor formula) is not necessarily the same, and the thickness is not necessarily the same, but it is between 2 〜 and 2 〇〇, and the growth temperature is also between 600 ° C and 1200 ° C. The total thickness of the contact layer 30 is between 2 and 5 μm, and comprises a total of 50 to 500 layers of gallium nitride based layer 3 〇 1 and an aluminum gallium nitride based layer 3 〇 2, at least one of which (whether GaN or GaN) The concentration of the Shixi pusher layer of the gallium base layer 3〇2) is greater than lxl〇19cm.3. The number of layers of the gallium nitride base layer 3〇1 and the nitrided gallium base layer 3〇2 is the same or the difference between the number of layers is one. The three figures are not intended to be a structure of a gallium nitride-based multiple quantum well light-emitting diode according to a second embodiment of the present invention. As shown in the third figure, the structure of this embodiment is identical to that of the first embodiment, the only difference The material used in the n-type contact layer 32 is different. The n-type contact layer % of this embodiment is composed of a plurality of layers of gallium nitride-based layer milk which is doped together with Shi Xi. And a superlattice structure formed by superimposing the gallium base layer 322 of the indium and the shixi together, wherein the energy gap of the nitriding layer 322 having the indium mixed with the indium is more doped than the indium and the material. The nitrite layer 32 of the nitriding layer is said to be in a layer of nitriding layer 1249866 321 with indium and shixi co-doped, superimposed with a layer of indium and antimony doped. An aluminum gallium nitride base layer 322, on which a layer of gallium nitride base layer 321 which is co-doped with indium and dream is superposed, and so on. Alternatively, the n-type contact layer is nitrided in the layer of indium. On the GaN base layer 322, the superimposed layer has a II filament layer 321 which is doped together by the marriage and the stone eve, a superimposed layer thereon, a layer of a nitride-based silicon layer 322 having a layer of indium, and so on. The thickness of the base layer does not have to be the same, but it is between 2〇Α and fine, and the growth temperature is 600. (:~~.C. The composition of each nitrided scale base layer does not have to be the same, the thickness does not have to be the same, but both are in 2 Between ~2()() Α, the growth temperature is also in the sub.c~i2〇( between rc. The total thickness of the n-type contact layer 32 is between 2~5μπι A total of 5 〇 5 〇〇 氮化 氮化 基 基 与 与 氮化 氮化 氮化 氮化 氮化 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中 其中〇1W3. The number of layers of the gallium nitride based layer is the same as that of the vaporized aluminum gallium base layer 322 or the difference between the number of layers is one. The fourth figure is based on the third embodiment of the present invention, the gallium nitride, the good weight well, the second light A schematic diagram of the structure of the polar body. As shown in the fourth figure, the structure of this embodiment is identical to that of the first and second embodiments, and the only difference is that the material used in the n-type contact layer 34 is different. The contact layer 34 is a superlattice structure composed of a layer of tantalum, a GaN-based layer which is co-doped with steel and Shi Xi, and a GaN layer 342 which is in-line doped with indium and Shi Xi. The energy gap of the nitride-based bridging layer 342 which is co-doped with indium and shixi is larger than that of the indium-doped co-doped brib-based layer 34i. More specifically, the 'n-type contact layer 34 is on a layer of nitrided gallium-based layer 341 which is doped with indium and shixi, superposed-layered with indium and ruthenium-doped nitriding layer 342, on which The superposition-layer has a Ni-Germanium layer doped with indium and Shixi, and so on. Alternatively, the _ contact layer 34 is formed on the layer of the nitrided fused base layer in which the indium and the stone are mixed, and the layer is indium and shi shi _ _ nitriding base layer tearing, and then superimposed thereon There is a 12,498,866 bismuth gallium base layer 342, which is in common with the indium, and so on. The thickness of each of the nitrogen and gallium layers does not have to be the same, but they are all between 20A and 200 people, and the growth temperature is in. Between c~12〇〇〇c. The composition of the adjacent nitrogen-delta-based layer is not (4), but the adjacent layers of the nitride-based layer may be different or different, and the thickness of each layer is not necessarily the same, but it is between 2〇2 and 2〇〇. The growth temperature is also between 600 ° C and 1200 ° C. The n-type contact layer 34 has a total thickness of between 2 and 5 μm, and comprises a total of 50 to 500 layers of a nitrided gallium base layer 341 and a nitrided gallium base layer 342, at least one of which (whether an aluminum gallium nitride based layer 341 or nitrided). The indium and antimony doping concentration of the aluminum gallium base layer 342) is greater than lxl019 cm·3. The number of layers of the nitrided gallium base layer 341 and the nitrided gallium base layer 342 is the same or the difference between the number of layers is one. Fig. 5 is a schematic view showing the structure of a gallium nitride-based multiple quantum well light-emitting diode according to a fourth embodiment of the present invention. As shown in the fifth figure, the structure of this embodiment is identical to that of the foregoing embodiment, except that the material used in the n-type contact layer 36 is different. The n-type contact layer % of this embodiment is a superlattice structure composed of a plurality of layers, an antimony-doped aluminum indium gallium nitride-based layer 361, and an antimony-doped aluminum indium gallium nitride layer 362. The energy gap of the yttrium-doped yttrium-indium-gallium-based layer 362 is larger than that of the yttrium-doped aluminum-indium-aluminum-based 361 layer. More specifically, the n-type contact layer 36 is on a layer of germanium-doped aluminum indium-phosphide-based layer 361, superposed with a layer of iridium-doped indium-phosphorus-based layer 362, and a layer of stone thereon. The doped aluminum nitride indium gallium nitride layer 361, and so on. Alternatively, the n-type contact layer 36 is formed on a layer of germanium-doped aluminum indium gallium nitride layer 362, superposed with a layer of germanium-doped aluminum indium gallium nitride layer 361, and a layer of germanium-doped nitrogen is superposed thereon. Aluminum indium gallium base layer 362, and so on. The thickness of each of the aluminum indium gallium nitride base layers is not necessarily the same, but is between 20 and 200 Torr, and the growth temperature is between 600 ° C and 1200 ° C. The composition of the adjacent aluminum indium gallium nitride base layers is different, but the composition of the non-adjacent aluminum indium gallium nitride layers may be the same or different from 1249866, and the thickness of each layer is not necessarily the same, but both are from 20 to 200 A. The growth temperature is also between 600. (Between: 1200 ° C. The total thickness of the n-type contact layer 36 is between 2 and 5 | ^ 1 , a total of 50 to 500 layers of aluminum nitride indium gallium nitride layer 361 and aluminum nitride indium gallium nitride layer 362, at least There is a sound (whether the aluminum indium gallium nitride base layer 361 or the aluminum indium gallium nitride base layer 362) has a germanium doping concentration greater than lxl019 cm3. The tantalum nitride indium gallium base layer 361 has the same number of layers as the nitrided indium gallium base layer 362 or The difference between the number of layers is one. In this embodiment, by combining two different compositions of aluminum indium gallium nitride AjjnnGhmN and AlpInqGa! Example N (0$m, n<l;0<p,q<l; The superlattice structure formed by m + n <i; p + qg 1; m < p) can obtain a low-doping concentration (> lxl 〇 19 cm -3 ) and a low-resistance n-type gallium nitride contact layer. In addition, by using the composition of aluminum, indium and gallium, a crystal film with matching lattice constants can be obtained without causing cracking due to heavy doping in the n-type gallium nitride contact layer, improving the heavy doping. The quality of the gallium nitride contact layer and the difficulty in manufacturing the n-type ohmic contact, which in turn greatly reduces the operating voltage of the entire gallium nitride-based multiple quantum well light-emitting diode. The present invention is not limited to the scope of the present invention, and the equivalent variations and modifications of the scope of the present invention should remain within the scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS The first figure shows the lattice constant (Lattice Constant) and the energy gap of the Group III nitride material. The second figure shows the gallium nitride-based multiple quantum well light-emitting diode according to the first embodiment of the present invention. 3 is a schematic diagram of a structure of a gallium nitride-based multiple quantum well light-emitting diode according to a second embodiment of the present invention, π 1249866. The fourth figure is a gallium nitride-based multiple quantum according to a third embodiment of the present invention. FIG. 5 is a schematic structural view of a gallium nitride-based multiple quantum well light-emitting diode according to a fourth embodiment of the present invention. [Description of Main Components] 10 Substrate 20 Buffer Layer 30 n-type Contact layer 32 n-type contact layer 34 n-type contact layer 36 n-type contact layer 40 negative electrode 42 light-emitting layer 50 p-type cladding layer 60 germanium-type contact layer 70 positive electrode 301 Heterogeneous gallium nitride based layer 302 germanium-doped aluminum gallium nitride based layer 321 indium and germanium doped gallium nitride based layer 322 indium and germanium doped aluminum gallium nitride based layer
_ 12 1249866 341 有銦與矽摻雜的氮化鋁鎵基層 342 有銦與矽摻雜的氮化鋁鎵基層 361 有矽摻雜的氮化鋁銦鎵基層 362 有矽摻雜的氮化鋁銦鎵基層_ 12 1249866 341 Indium and tantalum doped aluminum gallium nitride based layer 342 Indium and germanium doped aluminum gallium nitride based layer 361 germanium doped aluminum indium gallium nitride based layer 362 germanium doped aluminum nitride Indium gallium base
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