201117424 六、發明說明： 【發明所屬之技術領域】 本發明是有關於一種發光二極體，特別是指—種高出 光均勻性的發光二極體。 【先前技術】 參閱圖I，目前水平導通式的發光二極體（Light Emitting Diode ; LED )包含一基材 11、一作動層 12，及·— 電極單元13 ’該基材11是選自藍寶石為材料所構成，該作 • 動層12包括一與該基材11連接的η-型半導體層i2l，及一 連接在該η-型半導體層121部分表面並與該η-型半導體層 121形成ρ-η接面（p-n junction)的ρ-型半導體層122，兮 電極單元13具有一形成在該η-型半導體膜121表面的第一 電極131，及一與該ρ_型半導體層122連接的第二電極 132，該第一、二電極131、132可彼此配合提供電能至該 作動層12’該作動層12可以光電效應將接受之電能轉換成 光能後向外發出。 # 然而’由於上述之發光二極體經由該第二電極132注 入電流時，大部分之電流會以最靠近該第二電極132的周 圍注入至該η-型半導體層121及ρ·型半導體層122間的ρ-η 接面（p-n junction)，因此載子複合後發出的光會大部分集 中在靠近該第二電極132的鄰近區域，而使得發光二極體 的亮度極不均勻。 參閱圖2’因此，為了改善自該第二電極132電流注入 均勻性差的問題’目前則在上述該ρ·型半導體層丨22及該 201117424 第二電極132間設置一透明導電層123，藉由該透明導電層 123將自該第二電極132注入之電流先均勻擴散後再傳導至 該P-型半導體層122中，避免電流直接自該第二電極132 向該P-型半導體層122注入，而使得電流可均句通過該p_ 型半導體層122至該p-n接面，而得以提升出光均勻性。 雖然該透明導電層123可幫助電流自該第二電極132 注入時較為均勻的擴散進入該P-型半導體層122中，然而 由於夂到該第一電極131的影響，進入該透明導電層123 的電流仍會以最接近該第一電極131的路徑注入至該型 半導體層I22及該n_型半導體層m的p_n接面（p_n junction )，因此，仍然會有亮度不均勻的問題存在。 由於出光均勻性是LED元件應用時的一基本特性要 求，因此，如何提升電流注入的均勻性，以提升led元件 的發光效率及出光均勻性，一直是在此技術領域者不斷改 善的方向之一。 【發明内容】 因此’本發明之目的，即在提供一種具有高出光均勻 性及高發光效率的發光二極體。 於是’本發明一種發光二極體包含一基材、一作動 層、一絕緣層、一導電層，及一電極單元。 該作動層具有一與該基材連接的第一型半導體層，及 連接於該第一型半導體層部分表面向上延伸，且電性與 該第一型半導體層相反的第二型半導體層。 該‘絕緣層形成在該第二型半導體層表面，並具有多數 201117424 與該第二型半導體層連通的穿孔。 該導電層形成在該絕緣層上，經由該等穿孔與該第二 型半導體層電連接 該電極單元可配合提供電能至該作動層，該作動層可 在接受電能後以光電效應將接受之電能轉換成光能後向外 發出。 本發明之功效在於：利用設置在該作動層跟電極單元 之間的絕緣層在該作動層與該電極單元間形成電流障壁， 令自該第二電極注入之電流均勻擴散在該導電層，再利用 該等絕緣層之穿孔的電導通，而使電流得以擴散分佈後注 入至該作動層，進而有效提升發光二極體的發光效率及出 光均勻性。 【實施方式】 有關本發明之前述及其他技術内容、特點與功效，在 以下配合參考圖式之二個較佳實施例的詳細說明中將可 清楚的呈現。 本發明發光二極體的一第一較佳實施例是以水平導通 式的發光二極體為例作說明。 參閱圖3、圖4，圖4是選自圖3之a-a直線的剖視 圖，本發明該第一較佳實施例是包含一基材21、一作動層 22、一絕緣層23、一導電層24,及一電極單元25。 該基材21是由絕緣材料構成，由於該基材21的構成 材料為本技術領域者所周知，因此，在此不再多加贅述， 於本實施例中該基材21是由藍寶石為材料所構成。 201117424 矣/作動層22形成於該基材21 _L，具有-與該基材21 連接的第—型半導體層221，及—連接在該第—型半導 1 221的部份表面且電性與該第一型半導體層221相反 1二型半導體層222,該第一、二型半導體層221、222 形成P_n接面（卜n juncti〇n)。 5亥第―、二型半導體層221、222為分別選自具有n型 :雜或^型摻雜的m_v族半導體材料所構成，於本實施例 。亥第、一型半導體層221、2U是分別選自n型摻雜 及Ρ型換雜之氮化㈣半導料料所構成。 、、邑彖層23形成在該作動層22上，具有多數呈等間 隔分佈並與該第二型半導體層連通的穿孔231，該絕緣層 23為選自絕緣材料，例如氧化矽、氮化矽、氧化铪、氧化 ’·匕或其中之-組合為材料，於本實施例中該絕緣層Β是 由透明的氮化矽為材料所構成。 該導電層24形成在該絕緣層23，具有一覆蓋該絕緣層 23的層頂部24卜及多數自該層頂部241向下延伸並穿過 該等穿孔而與該第二型半導體層222電連接的柱部 。亥導電層24疋選自導電材料所構成’由於該導電層 24的構成材料為本技術領域者所周知，因此，在此不再: 加贅述，於本實施财該導電層24是由透明的氧化銦錫為 材料所構成。 該電極單元25具有-設置在該第-型半導體層221表 面且呈歐姆接觸（Ohmic contact)的第一電極251，及一形成 在該導電層24表面且與該導電層24呈歐姆接觸的第二電 201117424 於本實施例中’該第一、二電極251、252是選自 翻金為材料所構成。 、 卜界’盈由該第-、二電極25i、252施加外電屡至該 乍動層22時’自該第二電極252注人之電流由於該絕緣層 23—的障壁效果’因此會先均勻擴散至該層頂部241，接著 再藉由該等㈣242將均勾擴散在該層頂部⑷的電流導 λ第一型半導體層222中，而達到提升出光均勻性的目201117424 VI. Description of the Invention: [Technical Field] The present invention relates to a light-emitting diode, and more particularly to a light-emitting diode having high light uniformity. [Prior Art] Referring to FIG. 1, a horizontally-lit light emitting diode (LED) comprises a substrate 11, an actuation layer 12, and an electrode unit 13'. The substrate 11 is selected from the group consisting of sapphire The movable layer 12 includes an n-type semiconductor layer i2l connected to the substrate 11, and a surface connected to the surface of the n-type semiconductor layer 121 and formed with the n-type semiconductor layer 121. a p-type semiconductor layer 122 of a pn junction, the germanium electrode unit 13 has a first electrode 131 formed on a surface of the n-type semiconductor film 121, and a first electrode 131 connected to the p-type semiconductor layer 122 The second electrode 132, the first and second electrodes 131, 132 can cooperate with each other to provide electric energy to the actuating layer 12'. The actuating layer 12 can photoelectrically convert the received electric energy into light energy and then emit it outward. # However, when the above-mentioned light-emitting diode is injected with current through the second electrode 132, most of the current is injected to the n-type semiconductor layer 121 and the p-type semiconductor layer closest to the periphery of the second electrode 132. There are 122 pn junctions, so that the light emitted by the carrier recombination is mostly concentrated in the vicinity of the second electrode 132, so that the brightness of the light-emitting diode is extremely uneven. Referring to FIG. 2', in order to improve the problem of poor current injection uniformity from the second electrode 132, a transparent conductive layer 123 is disposed between the ρ-type semiconductor layer 22 and the 201117424 second electrode 132. The transparent conductive layer 123 uniformly diffuses the current injected from the second electrode 132 and then conducts the current into the P-type semiconductor layer 122 to prevent current from being directly injected from the second electrode 132 into the P-type semiconductor layer 122. The current uniformity can be improved by allowing the current to pass through the p_ type semiconductor layer 122 to the pn junction. Although the transparent conductive layer 123 can help the current to diffuse into the P-type semiconductor layer 122 more uniformly when the current is injected from the second electrode 132, the transparent conductive layer 123 enters the transparent conductive layer 123 due to the influence of the first electrode 131. The current is still injected into the p_n junction (p_n junction) of the semiconductor layer I22 and the n-type semiconductor layer m in the path closest to the first electrode 131, and therefore, there is still a problem of uneven brightness. Since the uniformity of light output is a basic characteristic requirement of LED components, how to improve the uniformity of current injection to improve the luminous efficiency and uniformity of light emission of LED components has been one of the continuous improvement directions in this technical field. . SUMMARY OF THE INVENTION Therefore, it is an object of the present invention to provide a light-emitting diode having high light uniformity and high light-emitting efficiency. Thus, a light-emitting diode of the present invention comprises a substrate, an active layer, an insulating layer, a conductive layer, and an electrode unit. The actuating layer has a first type semiconductor layer connected to the substrate, and a second type semiconductor layer extending upwardly from the surface of the first type semiconductor layer portion and electrically opposite to the first type semiconductor layer. The 'insulating layer is formed on the surface of the second type semiconductor layer and has a plurality of perforations that communicate with the second type semiconductor layer in 201117424. The conductive layer is formed on the insulating layer, and the electrode unit is electrically connected to the second type semiconductor layer via the through holes, and the electrode unit can cooperate to provide electric energy to the actuating layer, and the actuating layer can receive the electric energy by photoelectric effect after receiving the electric energy. It is emitted outward after being converted into light energy. The effect of the invention is that a current barrier is formed between the actuation layer and the electrode unit by using an insulating layer disposed between the actuation layer and the electrode unit, so that a current injected from the second electrode is uniformly diffused in the conductive layer, and then The electrical conduction of the perforations of the insulating layers is used to diffuse the current and then inject into the active layer, thereby effectively improving the luminous efficiency and uniformity of the light emitting diode. The above and other technical contents, features, and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments. A first preferred embodiment of the light-emitting diode of the present invention is described by taking a horizontally-conductive light-emitting diode as an example. Referring to FIG. 3 and FIG. 4, FIG. 4 is a cross-sectional view of a line selected from the aa of FIG. 3. The first preferred embodiment of the present invention comprises a substrate 21, an actuation layer 22, an insulating layer 23, and a conductive layer 24. And an electrode unit 25. The substrate 21 is made of an insulating material. Since the constituent material of the substrate 21 is well known in the art, it will not be further described herein. In the present embodiment, the substrate 21 is made of sapphire. Composition. 201117424 The 矣/actuating layer 22 is formed on the substrate 21_L, has a first-type semiconductor layer 221 connected to the substrate 21, and is connected to a portion of the surface of the first-type semiconductor 221 and electrically connected The first type semiconductor layer 221 is opposite to the first type II semiconductor layer 222, and the first and second type semiconductor layers 221 and 222 form a P_n junction (b). The 5th and 2nd semiconductor layers 221 and 222 are each selected from the group consisting of m-v semiconductor materials having an n-type: hetero or ^ type doping, in this embodiment. The hexa-type, first-type semiconductor layers 221 and 2U are each selected from the group consisting of n-type doping and ytterbium-type nitriding (tetra) semiconductive materials. The germanium layer 23 is formed on the active layer 22, and has a plurality of perforations 231 which are equally spaced and communicate with the second type semiconductor layer. The insulating layer 23 is selected from an insulating material such as hafnium oxide or tantalum nitride. The yttrium oxide, the oxidized yttrium or the like is combined into a material. In the present embodiment, the insulating layer Β is composed of transparent tantalum nitride as a material. The conductive layer 24 is formed on the insulating layer 23, and has a layer top 24 covering the insulating layer 23 and a plurality of holes extending from the top portion 241 of the layer and passing through the holes to be electrically connected to the second type semiconductor layer 222. Column. The conductive layer 24 is made of a conductive material. Since the constituent material of the conductive layer 24 is well known to those skilled in the art, it will not be repeated here: in the present embodiment, the conductive layer 24 is transparent. Indium tin oxide is composed of a material. The electrode unit 25 has a first electrode 251 disposed on the surface of the first-type semiconductor layer 221 and in an ohmic contact, and a first electrode formed on the surface of the conductive layer 24 and in ohmic contact with the conductive layer 24. In the present embodiment, the first and second electrodes 251 and 252 are selected from the group consisting of materials. When the external electrodes are applied to the turbulent layer 22 by the first and second electrodes 25i, 252, the current injected from the second electrode 252 is uniform due to the barrier effect of the insulating layer 23 Diffusion to the top 241 of the layer, and then by the (four) 242, the homogeny is diffused in the current-conducting λ first-type semiconductor layer 222 at the top of the layer (4), thereby achieving the purpose of improving the uniformity of light.
以避免習知僅以導電層123進行電流擴散時，電流會 觉到該第-電㉟131的影響而使得電流的流動會集中在靠 近u第一電極131、132周圍，所導致亮度不均勻的問 題，且由於該等穿孔231可令電流更均勻地注入該第二型 半導體層222而到達p_n接面（p_n juncti〇n)，因此得以增 加載子的複合效率，而可同時達到提升發光效率的另一目 的。 參閱圖5,值得一提的是，亦可藉由調整該等穿孔 的相對設置位置，而控制該等柱部242與該第二型半導體 層222的接觸位置，使電流注入至該作動層22的均句性可 進一步的提升，例如，該等穿孔231可如圖5所示為從鄰 近該第二電極252朝向該第一電極251方向呈由密到疏的 態樣分佈，如此可令電流較容易導入相對遠離該第—電極 251之位置’而減少該第一電極251對注入電流之均勻性的 影響。 又值得一提的是，該絕緣層23可由具有不同折射率之 透明絕緣材料堆疊構成，而形成一具有多重折射率之絕緣 201117424 層23 ’如此藉由不同折射率降低自該作動層 =:行進之光在接觸該絕緣層23時的全反射: 出率，而可更進-步提升該發光二極體的亮度。 /閱圖6、圖7’圖6是本發明發光二極體的一第 β例’是以垂直導通式的發光二極體為例作說明，圖7 是選自圖6之b-b直線的剖視圖。In order to avoid the fact that the current is only diffused by the conductive layer 123, the current will be affected by the influence of the first electric 35131, so that the current flow will be concentrated near the first electrodes 131, 132, resulting in uneven brightness. And because the through holes 231 can inject the current into the second type semiconductor layer 222 more uniformly and reach the p_n junction (p_n juncti〇n), thereby increasing the recombination efficiency of the carrier, and simultaneously achieving the improvement of the luminous efficiency. Another purpose. Referring to FIG. 5 , it is worth mentioning that the position of the contact between the pillars 242 and the second semiconductor layer 222 can be controlled by adjusting the relative positions of the vias to inject current into the active layer 22 . The uniformity can be further improved. For example, the through holes 231 can be distributed from the adjacent second electrode 252 toward the first electrode 251 in a dense to sparse manner as shown in FIG. It is easier to introduce a position away from the first electrode 251' to reduce the influence of the first electrode 251 on the uniformity of the injection current. It is also worth mentioning that the insulating layer 23 can be composed of a stack of transparent insulating materials having different refractive indices to form an insulating 201117424 layer 23' having multiple refractive indices. Thus, by different refractive index reductions from the actuating layer =: travel The total reflection of the light when contacting the insulating layer 23: the output rate, and the brightness of the light-emitting diode can be further increased. FIG. 6 is a cross-sectional view showing a β-th example of the light-emitting diode of the present invention taken as a vertical-conducting light-emitting diode, and FIG. 7 is a cross-sectional view taken from the line bb of FIG. .
該第二較佳實施例是包含一基材31、一作動層32、一 絕緣層33、一導電層34，及一電極單元& S 。亥基材31是由絕緣材料構成，由於該基材的構成 材料為本技術領域者所周知，因&，在此*再多加費述， 於本實施例巾該基材31是由藍寶石為材料所構成。 該作動層32形成於該基材31上，具有—與該基材^ 面連接的第-型半導體層321，及一連接在該第一型半導 體層321纟面且電性與該第一型半導體| m相反的第二 型半導體層322，該第-、二型半導體層321、322形成 接面（p-n junction),由於該第―、二型半導體層32i、M2 的構成材料與該第一較佳實施例相同，因此不再多加贅 述。 忒絕緣層33形成在該作動層32上，具有多數呈等間 隔分佈並與該第二型半導體層322連通的穿孔331 ^ 該導電層34形成在該絕緣層33上，具有一覆蓋該絕 緣層33的層頂部341，及多數自該層頂部341向下延伸並 穿過該等穿孔331而與該第二型半導體層322電連接的柱 部 342 〇 201117424 該電極單元35具有一設置在該基材31與該第一型半 導體層321之間的第-電極351，及一形成在該導電層μ 表面且與該導電層34呈歐姆接觸的第二電極352，由於該 絕緣層33、該導電層34,及該電極單元35的構成材料= 該第一較佳實施例相同，因此於此不再多加贅述。The second preferred embodiment comprises a substrate 31, an actuation layer 32, an insulating layer 33, a conductive layer 34, and an electrode unit & S. The base material 31 is made of an insulating material, and since the constituent material of the substrate is well known to those skilled in the art, it is further described here. In the present embodiment, the substrate 31 is made of sapphire. Made up of materials. The actuating layer 32 is formed on the substrate 31, has a first-type semiconductor layer 321 connected to the substrate, and is connected to the first-type semiconductor layer 321 and electrically connected to the first type a second semiconductor layer 322 opposite to the semiconductor | m, the first and second semiconductor layers 321, 322 form a pn junction, and a constituent material of the first and second semiconductor layers 32i and M2 and the first The preferred embodiment is the same and therefore will not be described again. A germanium insulating layer 33 is formed on the active layer 32, and has a plurality of vias 331 which are equally spaced and communicate with the second type semiconductor layer 322. The conductive layer 34 is formed on the insulating layer 33 and has a covering layer. a layer top 341 of 33, and a plurality of pillar portions 342 〇 201117424 extending downwardly from the top 341 of the layer and electrically connected to the second type semiconductor layer 322 through the through holes 331. The electrode unit 35 has a base portion disposed thereon. a first electrode 351 between the material 31 and the first type semiconductor layer 321, and a second electrode 352 formed on the surface of the conductive layer μ and in ohmic contact with the conductive layer 34, due to the insulating layer 33, the conductive The layer 34 and the constituent material of the electrode unit 35 are the same as the first preferred embodiment, and thus will not be further described herein.
當外界經由該第…二電極351、352施加外電壓至該 作動層32時’自該第二電極352注人之電流由於該絕緣層 33的障壁效果，因此會先均勻擴散至該層料⑷，接著 再藉由該等_ 342將均勻擴散在該層頂部341的電流導 入該第二型半導體1 322中，而可達到提升出光均句㈣ 目的。 參閱圖8 ’值得一提的是’亦可藉由調整該等穿孔331 的相對設置位置，而控制該等㈣342與該第二型半導體 層322的接觸位置，使電流注入至該作動層32的均勾性可 進-步的提升，例如，該等穿孔331可如目8所示為從鄰 近該第一電極352向遠離該第二電極352丨向呈由疏到密 的態樣分佈’如此可令電流較容易導入遠離該第一、二電 極351、352相對之區域，而可更提升注入電流之均勾性。 本發明利用設置在作動層跟第二電極之間的絕緣層， ^用亥、·㈣層先形成—電流障壁，先令電流在該層頂部均 2散接著再利用該等形成在該絕緣層的穿孔中的柱 而使均勾分散在該層頂部上的電流可藉由該等柱部均 性〆主入至4作動層’進而有效提升發光效率及出光均勻 1 ’並可再進—步利用該等孔洞的相對設置位置而使電流 201117424 注入至該作動層的均勻性可推一半<丨 J『1進步的提升，同時還可再利 用絕緣層的多重折射率設計，降低自該作動層發出之光在 接觸該絕緣層時的全反射機率，而可進一步提升該發光二 極體的光取出率，故確實可達到本發明之目的。 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 範圍及發明說明内容所作之簡單的等效變化與修飾皆仍 屬本發明專利涵蓋之範圍内。 【圖式簡單說明】 圖1是一側視示意圖，說明習知水平導通式的發光二 極體結構； 圖2是一側視示意圖，說明習知具有導電層之水平導 通式的發光二極體結構； 圖3是一俯視示意圖，說明本發明第一較佳實施例的 發光二極體結構； 圖4是圖3中a-a直線的剖視示意圖； 圖5是一俯視示意圖，說明本發明第一較佳實施例之 該等穿孔分布的另一態樣； 圖6是一俯視示意圖，說明本發明第二較佳實施例的 發光二極體結構； 圖7是圖6中b-b直線的剖視示意圖；及 圖8是一剖視不意圖，說明本發明第二較佳實施例之 s亥等穿孔分布的另一態樣。 10 201117424 【主要元件符號說明】 21 基材 31 基材 22 作動層 32 作動層 221 第一型半導體層 321 第一型半導體層 222 第二型半導體層 322 第二型半導體層 23 絕緣層 33 絕緣層 231 穿孔 331 穿孔 24 導電層 34 導電層 241 層頂部 341 層頂部 242 柱部 342 柱部 25 電極單元 35 電極單元 251 第一電極 351 第一電極 252 第二電極 352 第二電極When an external voltage is applied to the actuating layer 32 via the second electrode 351, 352, the current injected from the second electrode 352 is uniformly diffused to the layer (4) due to the barrier effect of the insulating layer 33. Then, the current uniformly diffused on the top portion 341 of the layer is introduced into the second type semiconductor 1 322 by the _342, and the purpose of enhancing the light average sentence (4) can be achieved. Referring to FIG. 8 'it is worth mentioning', the position of contact between the (four) 342 and the second type semiconductor layer 322 can be controlled by adjusting the relative positions of the through holes 331 to inject current into the actuating layer 32. The uniformity can be improved. For example, the perforations 331 can be distributed from the first electrode 352 adjacent to the second electrode 352 toward the dense and dense state as shown in FIG. The current can be easily introduced away from the region opposite to the first and second electrodes 351 and 352, and the uniformity of the injection current can be further improved. The invention utilizes an insulating layer disposed between the active layer and the second electrode, and first forms a current barrier with a layer of hai, and (four) layers, and a current is first dispersed at the top of the layer and then used to form the insulating layer. The column in the perforation so that the current distributed on the top of the layer can be mainly introduced into the 4 actuation layer by the column portion, thereby effectively improving the luminous efficiency and uniformity of light emission 1 ' and can be further advanced By using the relative positions of the holes, the uniformity of the current 201117424 injected into the actuation layer can be increased by half, and the multi-refractive index design of the insulating layer can be reused to reduce the self-operation. The total reflection probability of the light emitted by the layer when contacting the insulating layer can further increase the light extraction rate of the light-emitting diode, so that the object of the present invention can be achieved. The above is only the preferred embodiment of the present invention, and the scope of the present invention is not limited thereto, that is, the simple equivalent changes and modifications made by the scope of the invention and the description of the invention are all It is still within the scope of the invention patent. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view showing a light-emitting diode structure of a conventional horizontal guide; FIG. 2 is a side view showing a horizontally-conductive light-emitting diode having a conductive layer. 3 is a top plan view showing a structure of a light emitting diode according to a first preferred embodiment of the present invention; FIG. 4 is a cross-sectional view showing a line of aa in FIG. 3; and FIG. 5 is a top plan view showing the first aspect of the present invention. FIG. 6 is a top plan view showing the structure of the light emitting diode according to the second preferred embodiment of the present invention; FIG. 7 is a cross-sectional view showing the line bb of FIG. And FIG. 8 is a cross-sectional view showing another aspect of the perforation distribution of the second preferred embodiment of the present invention. 10 201117424 [Description of main components] 21 substrate 31 substrate 22 actuation layer 32 actuation layer 221 first type semiconductor layer 321 first type semiconductor layer 222 second type semiconductor layer 322 second type semiconductor layer 23 insulating layer 33 insulating layer 231 Perforation 331 Perforation 24 Conductive layer 34 Conductive layer 241 Layer top 341 Layer top 242 Column portion 342 Column portion 25 Electrode unit 35 Electrode unit 251 First electrode 351 First electrode 252 Second electrode 352 Second electrode