200917526 九、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，特別是指一種具有 光子晶體（photonic crystal)結構以提昇其外部量子效率 (external quantum efficiency)之發光二極體。 【先前技術】 發光二極體所具有的體積小、重量輕、反應速度快等 優點’使其逐漸地取代傳統光源而作為照明使用。已知的 常見應用如大型戶外顯示看板、交通指示燈號，以及液晶 顯示器背光源等。 而為了實現如汽車車燈、投影機用光源等更高亮度需 求的應用’仍然必須在發光效率上進行提昇，以進一步增 加其發光亮度。 習知一種用以增加發光二極體發光效率的方法，在發 光二極體之半導體結構下方，加入一反光層。以使半導體 結構朝下發出之光線可經由反光層的反射向上發出，以提 高整體發光二極體之向上的發光亮度。 該反光層通常為鋁、銀，或金等具有高反射率之金屬 材料所製成’但由於此類之金屬材料並無法對可見光區所 有波長之光線進行完全反射，且容易在施加電壓時於其 與半導體材料之介面處產生電致遷移等材料劣化現象，以 致反射特性劣化。 或者，以介電層堆疊而成之分布式布拉格反射器 (distributed Bragg re細〇r)結構取代上述金屬材質反光層， 200917526 雖可避開上述材料劣化之缺點，但其依循干涉原理所得之 反射特性，使其僅在正向方向對入射光線具有力乎百分之 百的反射率，斜向入射光線之反射率則無法達到百分2百 ，也就是③，上述此类貝用以提高發光二極體向上發光亮度 之反射器的反射率仍有待改進之空間。 X儿又 【發明内容】 一本發月t目的’即在提供一種具有光子晶體結構以 提高發光亮度之發光二極體。 本發明之另-目的，在於提供上述具有光子晶體結構 之發光二極體的製作方法。 於是，本發明提供-種具有光子晶體結構之發光二極 體’包含一基板、一半導體結構’以及一一維光子晶體結 構。 半導體結構設於基板上方，半導體結構在受電激發時 ’可發出位於一峰值波長範圍内之光線；一維光子晶體結 構設於基板與半導體結構之間，—維光子晶體結構具有一 對應涵蓋峰值波長範圍之完全光子能帶間隙。 此外，本發明更提供-種上述具有光子晶體結構之發 光二極體之製作方法，包含下列步驟： (A) 提供-形成有—半導體結構之蟲晶用基板； (B) 於半導體結構上形成—透明電極； (C) 於透明電極上形成--維光子晶體結構； (D) 形成至少一貫設於'維光子晶體結構並電性 接觸透明電極之導電柱； 200917526 ⑻形成-電性接觸導電柱之第一電極於一維光 子晶體結構上； (F)提供一其上形成有接合金屬層之基板將第 一電極接合於接合金屬層； ⑹將蟲晶用基板自半導體結構上移除；以及 (H)於半導體結構上形成一第二電極。 、本發明藉由在半導體結構下方設置—維光子晶體結構 ，並依半導體結構所具有之峰值波長範圍調整—維光子晶 體結構’使半導體結構朝—維光子晶體結構發出之光線， 可近乎百分之百的反射，以提高整體發光二極體之發光亮 度。 【實施方式】 在本發明被詳細描述之前，要注意的是，在以下的說 明内合中’類似的元件是以相同的編號來表示。 如圖1所不，本發明具有光子晶體結構之發光二極體 匕3基板21、-設置於基板21上之接合金屬層u、一 設於接合金屬| 22上之第一電極23、一設於第一電極Μ 上之一維光子晶體結構24、至少一貫設於一維光子晶體結 構24内並與第-電極23電性連接之導電柱、—設於一 維光子晶體結# 24上並與導電柱25電性連接之透明電極 26、-設於透明電極26上之半導體結構27，以及_設於半 導體結構27上之第二電極28。 基板21採用散熱性較佳之石夕基板或金屬基板。 接合金屬層22包含二層結構，由下而上依序包含欽 200917526 (Ti)層以及金（au)層。 第電極23為鉻鉑金（Cr/Pt/Au)三層結構之金屬層，其 中金層接觸於接合金屬層22之金層。 一維光子晶體結構24包含有多數堆疊之介電層對 (dielectric layer pair)，各介電層對具有二層疊且為折射率相 異之介電層。丨中’各介電層之材質為氧化鈦、氧化矽、 氮化石夕或氧化组之其中-者。該等介電層對的數量介於5 至20之間。各該介電層之厚度介於3〇至2〇此爪之間。 藉由調整兩介電層的折射率及厚度可決定一完全光子 能帶間隙（completely photonic band gap ; CPBG)。有關介電 層的折射率及厚度與完全光子能帶間隙之間的關係，其原 理可參閱美國專利第6，130,780號案。當中揭示了光子能量 位在該完全光子能帶間隙中的光子，無法於該一維光子晶 體結構24巾進行_。因此，不論各種方向或是各種偏極 I"生入射於一維光子晶體結構24的光線，只要其光子能量是 落在該光子晶體能帶間隙之中，皆會被—維光子晶體結構 24所反射。 由於一維光子晶體結構24為介電材質所構成，阻隔了 第-電極23對半導體結構27的供電，因此，本發明以與 第-電極23電性連接之導電柱25及透明電極％，來間接 對半導體結構27進行供電。並且，透明電極％亦大致上 不會對半導體結構27與一維光子晶體結構24之間的光線 傳播造成影響。 ' 導電柱25材質為鎳金（Ni/Au)金屬層，導電柱25之直 200917526 徑為50/xm，高度為7μιη，實際實施時不以此限。透明電極 26為透明且可導電之材質如銦錫氧化物（ιτο)所製成。透明 電極26之厚度為3000Α。 半導體結構27可受電激發而發出光線，包含同為氮化 叙（GaN)為基質之一 ρ型半導體層271、一 η型半導體層 272’以及—介於ρ型半導體層271及η型半導體層272之 間的發光半導體層273。其中，發光半導體層273具有多重 ΐ子井（multi-quantum well)結構。此半導體結構27所發出 光線之波長大致位於一峰值波長（peak waveiength)範圍内。 為了可完全反射由半導體結構27所發出並以各方向入 射於一維光子晶體結構24之光線，此處需對應調整一維光 子晶體結構24中之兩介電層之折射率及厚度，使其完全光 子能帶間隙對應於半導體結構27之峰值波長範圍。 此外，為更加強整體發光二極體之光引出效率（Hght extraction efficiency) ’本發明更於n型半導體層272未受第 -電極28所覆蓋而露出的上表面形成有粗糙化結構⑺。 第二電極28為鉻金（Cr/Au)金屬材質所製成。 有關上述本發明具有光子晶體結構之發光二極體的製 作方法，包含有下列步驟： 首先如圖2所不，提供一其上形成有半導體結構27 之蟲晶用基板20;半導體&接γ 卞等體結構27由下而上依序包含同為氮 化鎵（GaN)為基質之η型半導許恳 找，L若 主千導體層272、發光半導體層273 ，以及P型半導體層271。 蟲晶用基板20 之材質為藍寶石（sapphire)等晶格常數與 200917526 半導體結構27相近之基板材質，以便於其上以有機金屬化 學氣相沉積（metal organic chemical vapor phase deposition) 磊晶成長半導體結構27。並且，為更順利磊晶成長半導體 結構27,於半導體結構27形成前，更先於磊晶用基板2〇 上形成一約50nm厚之氮化鎵緩衝層29。 其次，如圖3所示，於半導體結構27上形成透明電極 26。其形成方法可利用蒸鍍、濺鍍等物理性氣相沉積方法 為之。並且’再料明電極26上堆疊形成複數介電層對作 為一維光子晶體結# 24 ’各介電層對具有二層疊且折射率 相’、之’丨電層’形成方法可以物理或化學氣相沉積法為之 接著，如圖4所示，形成至少一貫設於一維光子晶體 結構24並電性接觸透明電極26之導電柱25 ;其中，導電 疋於《亥等；|電層對上以微景多及姓刻先形成貫孔，然後 於貫孔内以沉積方式填人以錄金(Ni/Αιι)等金屬所形成。 然後’如圖5所示，於―維光子晶體結構24上形成電 性接觸導電柱25之第一電極23，其形成方法可以物理或化 學氣相沉積法為之。 另#面，如圖6所示，提供一其上形成有接合金屬 曰 板21基板21採用具有較佳傳熱係數之矽基板 5屬土板並且，將蟲晶用基板20上之第一電極23經 過高溫，壓-段時間接合於基板21之接合金屬層Μ上。 :如圖7所7F ’將蟲晶用基板20以雷射剝離（laser lift-off)法自該丰導於 導體、、·。構27上移除，利用準分子（excimer) 10 200917526 雷射所產生之波長為248nm、脈衝寬度為25ns之的雷射光 ，照射以破壞於磊晶用基板20與半導體結構27之間的緩 衝層29，使磊晶用基板20與半導體結構27分離，以移除 蠢晶用基板20。 然後，如圖8所示，依序以硫酸等酸液以及電漿依序 對半導體結構27表面上所殘留之氮化鎵緩衝層材料進行蝕 刻清除。並且，利用電感耗合式電漿（inductive coupled plasma)自半導體結構27表面向下蝕刻至第一電極23，以區 隔出各發光二極體晶粒（die or chip)。 此外，更對半導體結構27之η型半導體層272上表面 進行粗糙化處理。該粗糙化處理可利用光致電化學（photo-electrochemical)# 刻 或其他 習用之I虫 刻方法 進行。 最後，如圖1所示，於該半導體結構27之η型半導體 層272上表面以習知半導體製程形成第二電極28，即完成 本發明發光二極體之製作。 以下以擇定本發明發光二極體之光子晶體結構之各介 電層材質為例，更具體地說明本發明之内容。 <實施例> 首先，選定以氧化鈦及氧化矽作為本發明發光二極體 之一維光子晶體結構中的介電層材質，已知氧化鈦及氧化 矽之折射率分別為2.52及1.48，計算後可得如圖9所示之 的光子能帶（photonic band)結構圖，然後，並在能帶的間隙 中擇訂一最佳的完全光子能帶間隙CPBG，完全光子能帶間 隙CPBG之頻率（frequency (c/a))之上限值及下限值分別為 11 200917526 0.304及0.282，並藉以計算得出所需之氧化欽層及氧化石夕 層的厚度分別為〇.421a及〇.579a，其中c為光速（喻 speed)、a 為晶格常數（lattice constant)。 另一方面，如圖10所示，依照半導體結構的峰值波長 範圍，對應設定完全光子能帶間隙CPBG之中心值，本實 施例中峰值波長以455nm為例，故將CPBG之中心值對應 設為455mn，經過計算得出晶格常數3為133nm，以及完全 光子能帶間隙之兩邊界波長分別為437nm及472nm，並推 算出氧化鈦層（Ti〇2)及氧化矽層（Si〇2)之厚度分別為56nm 及77nm，據以製作一維光子晶體結構，如圖u之電子顯微 鏡照片所示。 將本發明具有光子晶體結構之發光二極體與習知具有 鋁反光層之發光二極體進行比較，如圖12所示，在施加任 何電流值之情況下，不論在外部量子效率（external quamum efficiency)方面，或疋在光輸出功率（⑽印加方面，本 發明具有光子晶體結構之發光二極體皆優於習知具有鋁反 光層之發光二極體。 此外，如圖13所示，將本發明具有光子晶體結構之發 光二極體與習知具有鋁反光層之發光二極體在各反射角之 光輸出強度進行比較，可看出在3〇度至15〇度之角度範圍 内’本發明之發光二極體的光輸出強度皆優於習知具有鋁 反光層之發光二極體的光輸出強度。 歸納上述’本發明藉由在半導體結構27下方設置一維 光子晶體結構24 ’並依循半導體結構27之峰值波長範圍調 12 200917526 整一維光子晶體結構24之完全光子能帶間隙cpBG，使半 導體結構27所發出而以各種方向以及各種偏極性入射於一 維光子晶體結構24之光線可近乎百分之百的向上反射，不 但可避免習知鋁反光層材料劣化之問題，並更可較鋁反光 層提高反光率’以提高整體發光二極體向上之發光亮度， 確實達成本發明之功效。 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是本發明具有光子晶體結構之發光二極體的示意 圖； 圖2至圖8是本發明具有光子晶體結構之發光二極體 之製作方法的示意圖； 圖9是本發明具有光子晶體結構之發光二極體的實施 例的光子能帶結構圖； 圖10是圖9之實施例的光譜示意圖； 圖11是圖9之實施例的電子顯微鏡照片； 圖12是圖9之實施例相較於習知具有紹反光層之發光 二極體的電流對外部量子效率及光輸出強度之示意圖；以 及 圖13是圖9之實施例相較於習知具有鋁反光層之發光 二極體的各方向光輸出強度示意圖。 13 200917526 【主要元件符號說明】 20···· 日日用基板 27···.. …半導體結構 21 · •…基板 271… •••P型半導體層 22·... …·接合金屬層 272… •••η型半導體層 23..·· —第 電極 273… …發光半導體層 24···· -----維光子晶體結構 274… …粗糙化結構 25 ···· •…導電柱 28••… …第二電極 26..·· •…透明電極 29••… …緩衝層 14200917526 IX. DESCRIPTION OF THE INVENTION: TECHNICAL FIELD The present invention relates to a light-emitting diode, and more particularly to a light-emitting diode having a photonic crystal structure to enhance its external quantum efficiency. Polar body. [Prior Art] The advantages of the small size, light weight, and fast response speed of the light-emitting diode have been gradually replaced by conventional light sources for use as illumination. Commonly known applications such as large outdoor display panels, traffic light numbers, and LCD backlights. In order to achieve higher brightness requirements such as automotive lamps and projectors, it is still necessary to increase the luminous efficiency to further increase its luminous brightness. A method for increasing the luminous efficiency of a light-emitting diode is known, and a light-reflecting layer is added under the semiconductor structure of the light-emitting diode. The light emitted so that the semiconductor structure is directed downward can be emitted upward through the reflection of the light reflecting layer to increase the upward luminance of the entire light emitting diode. The light reflecting layer is usually made of a metal material having high reflectivity such as aluminum, silver, or gold. However, since such a metal material cannot completely reflect light of all wavelengths in the visible light region, and is easy to apply voltage A phenomenon of deterioration of a material such as electromigration occurs at the interface with the semiconductor material, so that the reflection characteristics are deteriorated. Alternatively, the distributed Bragg resurfacing structure formed by stacking dielectric layers replaces the above-mentioned metal reflective layer, and 200917526 can avoid the disadvantages of the above materials, but the reflection obtained by the interference principle The characteristic is that it only has 100% reflectivity to the incident light in the forward direction, and the reflectivity of the oblique incident light cannot reach 200%, that is, 3, which is used to improve the light emitting diode The reflectivity of the reflector that illuminates the brightness still has room for improvement. X children again [Summary of the Invention] A present invention provides a light-emitting diode having a photonic crystal structure to increase the luminance of the light. Another object of the present invention is to provide a method of fabricating the above-described light-emitting diode having a photonic crystal structure. Accordingly, the present invention provides a light-emitting diode having a photonic crystal structure comprising a substrate, a semiconductor structure, and a one-dimensional photonic crystal structure. The semiconductor structure is disposed above the substrate, and the semiconductor structure emits light in a peak wavelength range when excited by electricity; the one-dimensional photonic crystal structure is disposed between the substrate and the semiconductor structure, and the photonic crystal structure has a corresponding peak wavelength. The complete photon energy of the range has a gap. In addition, the present invention further provides a method for fabricating the above-described light-emitting diode having a photonic crystal structure, comprising the steps of: (A) providing a substrate for a crystallite formed with a semiconductor structure; (B) forming a semiconductor structure. - a transparent electrode; (C) forming a dimensional photonic crystal structure on the transparent electrode; (D) forming a conductive pillar at least consistently disposed in the 'photonic crystal structure and electrically contacting the transparent electrode; 200917526 (8) forming - electrical contact conduction The first electrode of the column is on the one-dimensional photonic crystal structure; (F) providing a substrate on which the bonding metal layer is formed to bond the first electrode to the bonding metal layer; (6) removing the substrate for the insect crystal from the semiconductor structure; And (H) forming a second electrode on the semiconductor structure. According to the present invention, by providing a -dimensional photonic crystal structure under the semiconductor structure and adjusting the peak wavelength range of the semiconductor structure - the photonic crystal structure 'the light emitted from the semiconductor structure toward the -dimensional photonic crystal structure can be nearly 100% Reflection to increase the brightness of the overall light-emitting diode. [Embodiment] Before the present invention is described in detail, it is to be noted that in the following description, similar elements are denoted by the same reference numerals. As shown in FIG. 1, the present invention has a photodiode structure of a light-emitting diode 匕3 substrate 21, a bonding metal layer u disposed on the substrate 21, and a first electrode 23 disposed on the bonding metal|22. a one-dimensional photonic crystal structure 24 on the first electrode 、, a conductive pillar at least consistently disposed in the one-dimensional photonic crystal structure 24 and electrically connected to the first electrode 23, is disposed on the one-dimensional photonic crystal junction #24 A transparent electrode 26 electrically connected to the conductive post 25, a semiconductor structure 27 disposed on the transparent electrode 26, and a second electrode 28 disposed on the semiconductor structure 27. The substrate 21 is a stone substrate or a metal substrate which is preferably heat-dissipating. The bonding metal layer 22 includes a two-layer structure including a Qin 200917526 (Ti) layer and a gold (au) layer from bottom to top. The first electrode 23 is a metal layer of a chrome platinum (Cr/Pt/Au) three-layer structure in which the gold layer is in contact with the gold layer of the bonding metal layer 22. The one-dimensional photonic crystal structure 24 comprises a plurality of stacked dielectric layer pairs, each dielectric layer pair having a two-layered dielectric layer having a different refractive index. The material of each dielectric layer in the crucible is titanium oxide, cerium oxide, cerium nitride or an oxidation group. The number of such dielectric layer pairs is between 5 and 20. Each of the dielectric layers has a thickness between 3 〇 and 2 〇 between the jaws. A complete photonic band gap (CPBG) can be determined by adjusting the refractive index and thickness of the two dielectric layers. The relationship between the refractive index and thickness of the dielectric layer and the complete photonic band gap can be found in U.S. Patent No. 6,130,780. Photons in which the photon energy is located in the gap of the complete photonic band are disclosed, and cannot be performed on the one-dimensional photonic crystal structure. Therefore, regardless of various directions or various polar I" rays incident on the one-dimensional photonic crystal structure 24, as long as the photon energy falls within the gap of the photonic crystal band, the photonic crystal structure 24 reflection. Since the one-dimensional photonic crystal structure 24 is made of a dielectric material, the power supply of the semiconductor structure 27 by the first electrode 23 is blocked. Therefore, the present invention uses the conductive pillar 25 and the transparent electrode % electrically connected to the first electrode 23 to The semiconductor structure 27 is powered indirectly. Moreover, the transparent electrode % also does not substantially affect the light propagation between the semiconductor structure 27 and the one-dimensional photonic crystal structure 24. The conductive pillar 25 is made of a nickel-gold (Ni/Au) metal layer, and the conductive pillar 25 has a diameter of 50/xm and a height of 7 μm. The actual implementation is not limited thereto. The transparent electrode 26 is made of a transparent and electrically conductive material such as indium tin oxide (ITO). The thickness of the transparent electrode 26 is 3000 Å. The semiconductor structure 27 can be electrically excited to emit light, and includes a p-type semiconductor layer 271, a n-type semiconductor layer 272', and a p-type semiconductor layer 271 and an n-type semiconductor layer. A light emitting semiconductor layer 273 between 272. Among them, the light-emitting semiconductor layer 273 has a multi-quantum well structure. The wavelength of the light emitted by the semiconductor structure 27 is approximately within a range of peak wavelengths. In order to completely reflect the light emitted by the semiconductor structure 27 and incident on the one-dimensional photonic crystal structure 24 in various directions, the refractive index and thickness of the two dielectric layers in the one-dimensional photonic crystal structure 24 need to be adjusted accordingly. The full photon band gap corresponds to the peak wavelength range of the semiconductor structure 27. Further, in order to further enhance the light extraction efficiency of the entire light-emitting diode, the present invention has a roughened structure (7) formed on the upper surface of the n-type semiconductor layer 272 which is not covered by the first electrode 28. The second electrode 28 is made of a chrome (Cr/Au) metal material. The method for fabricating the light-emitting diode having the photonic crystal structure of the present invention comprises the following steps: First, as shown in FIG. 2, a substrate 20 for a crystallite having a semiconductor structure 27 formed thereon; a semiconductor & The 卞-equivalent structure 27 includes an n-type semi-conducting layer which is the same as gallium nitride (GaN) as a matrix from bottom to top, L if the main thousand conductor layer 272, the light-emitting semiconductor layer 273, and the P-type semiconductor layer 271 . The material of the substrate 20 for insect crystal is a substrate material having a lattice constant similar to that of the 200917526 semiconductor structure 27, such as sapphire, so as to facilitate the epitaxial growth of the semiconductor structure by metal organic chemical vapor phase deposition. 27. Further, in order to more smoothly epitaxially grow the semiconductor structure 27, a gallium nitride buffer layer 29 having a thickness of about 50 nm is formed on the epitaxial substrate 2A before the semiconductor structure 27 is formed. Next, as shown in FIG. 3, a transparent electrode 26 is formed on the semiconductor structure 27. The formation method can be carried out by a physical vapor deposition method such as evaporation or sputtering. And 'recommended to form a plurality of dielectric layer pairs on the bright electrode 26 as a one-dimensional photonic crystal junction # 24 'each dielectric layer pair has a two-layer and refractive index phase ', the 'electrical layer' formation method can be physical or chemical The vapor deposition method is followed by, as shown in FIG. 4, forming a conductive pillar 25 which is at least consistently disposed on the one-dimensional photonic crystal structure 24 and electrically contacts the transparent electrode 26; wherein, the conductive layer is in the "Hai et al; On the top, the micro-jing and the surname are used to form the through-hole, and then filled in the through-hole to form a metal such as gold (Ni/Αιι). Then, as shown in Fig. 5, a first electrode 23 electrically contacting the conductive post 25 is formed on the "dimensional photonic crystal structure 24" by a physical or chemical vapor deposition method. In addition, as shown in FIG. 6, a substrate 21 on which the metal plate 21 is formed is provided with a substrate 5 having a preferred heat transfer coefficient, and the first electrode on the substrate 20 for the insect crystal is provided. After a high temperature, the bonding is performed on the bonding metal layer of the substrate 21 at a high pressure. As shown in Fig. 7 and 7F', the substrate 20 for insect crystals is guided from the conductor to the conductor by a laser lift-off method. The structure 27 is removed, and the laser light having a wavelength of 248 nm and a pulse width of 25 ns generated by an excimer 10 200917526 laser is irradiated to break the buffer layer between the epitaxial substrate 20 and the semiconductor structure 27. 29. The epitaxial substrate 20 is separated from the semiconductor structure 27 to remove the amorphous substrate 20. Then, as shown in Fig. 8, the gallium nitride buffer layer material remaining on the surface of the semiconductor structure 27 is sequentially etched away by an acid solution such as sulfuric acid and a plasma in sequence. Further, the surface of the semiconductor structure 27 is etched down from the surface of the semiconductor structure 27 to the first electrode 23 by inductively coupled plasma to distinguish the die or chip. Further, the upper surface of the n-type semiconductor layer 272 of the semiconductor structure 27 is further roughened. This roughening treatment can be carried out by photo-electrochemical #刻 or other conventional I insect method. Finally, as shown in FIG. 1, the second electrode 28 is formed on the upper surface of the n-type semiconductor layer 272 of the semiconductor structure 27 by a conventional semiconductor process, that is, the fabrication of the light-emitting diode of the present invention is completed. Hereinafter, the contents of the respective layers of the photonic crystal structure of the light-emitting diode of the present invention will be exemplified, and the contents of the present invention will be more specifically described. <Examples> First, titanium oxide and cerium oxide were selected as the dielectric layer material in the one-dimensional photonic crystal structure of the light-emitting diode of the present invention. It is known that the refractive indices of titanium oxide and cerium oxide are 2.52 and 1.48, respectively. After calculation, a photonic band structure diagram as shown in FIG. 9 can be obtained, and then an optimal full photon band gap CPBG is selected in the gap of the band, and the complete photon band gap CPBG is selected. The frequency (c/a) upper and lower limits are 11 200917526 0.304 and 0.282, respectively, and the required thicknesses of the oxidized layer and the oxidized stone layer are calculated as 421.421a and 〇.579a, where c is the speed of light (a speed) and a is a lattice constant. On the other hand, as shown in FIG. 10, according to the peak wavelength range of the semiconductor structure, the center value of the full photon band gap CPBG is set. In the present embodiment, the peak wavelength is 455 nm, so the center value of the CPBG is set to be corresponding. 455mn, after calculation, the lattice constant 3 is 133nm, and the two boundary wavelengths of the complete photon band gap are 437nm and 472nm, respectively, and the titanium oxide layer (Ti〇2) and the yttrium oxide layer (Si〇2) are derived. The thicknesses are 56 nm and 77 nm, respectively, and a one-dimensional photonic crystal structure is produced, as shown in the electron micrograph of FIG. Comparing the light-emitting diode of the present invention having a photonic crystal structure with a conventional light-emitting diode having an aluminum light-reflecting layer, as shown in FIG. 12, in the case of applying any current value, regardless of external quantum efficiency (external quamum) In terms of efficiency, or in terms of light output power ((10), the light-emitting diode of the present invention having a photonic crystal structure is superior to the conventional light-emitting diode having an aluminum reflective layer. Further, as shown in FIG. The light-emitting diode having the photonic crystal structure of the present invention is compared with the light-emitting diode of the conventional aluminum reflective layer at a light output intensity of each reflection angle, and can be seen in an angular range of 3 to 15 degrees. The light output intensity of the light-emitting diode of the present invention is superior to the light output intensity of the conventional light-emitting diode having the aluminum light-reflecting layer. The present invention is summarized in the present invention by providing a one-dimensional photonic crystal structure 24 under the semiconductor structure 27. And according to the peak wavelength range of the semiconductor structure 27, 12 200917526, the complete photon energy band gap cpBG of the entire one-dimensional photonic crystal structure 24, so that the semiconductor structure 27 is emitted and various The light incident on the one-dimensional photonic crystal structure 24 with various polarities can be nearly 100% upward reflection, which not only avoids the problem of deterioration of the conventional aluminum reflective layer material, but also improves the reflectance of the aluminum reflective layer to improve the overall illumination. The above-mentioned illuminating brightness of the diode is indeed the effect of the present invention. However, the above is only the preferred embodiment of the present invention, and the scope of the present invention cannot be limited thereto, that is, the patent application according to the present invention The simple equivalent changes and modifications made by the scope of the invention and the description of the invention are still within the scope of the present invention. [Fig. 1 is a schematic view of a light-emitting diode having a photonic crystal structure of the present invention; 2 to FIG. 8 are schematic views showing a method of fabricating a light-emitting diode having a photonic crystal structure according to the present invention; and FIG. 9 is a view showing a photonic band structure of an embodiment of the light-emitting diode having a photonic crystal structure according to the present invention; Figure 9 is an optical micrograph of the embodiment of Figure 9; Figure 12 is an embodiment of Figure 9 compared to the conventional one. Schematic diagram of the current versus external quantum efficiency and light output intensity of the light-emitting diode of the reflective layer; and FIG. 13 is the light output intensity of the light-emitting diode of the embodiment of FIG. 9 compared with the conventional light-emitting diode having the aluminum reflective layer Fig. 13 200917526 [Description of main component symbols] 20···· Daily substrate 27···.....Semiconductor structure 21 ·•...Substrate 271...•••P-type semiconductor layer 22·... Metal layer 272...•••n-type semiconductor layer 23..··-electrode 273...light-emitting semiconductor layer 24····--dimensional photonic crystal structure 274...roughened structure 25···· •...conductive post 28••...second electrode 26....··...transparent electrode 29••...buffer layer 14