1269506 九、發明說明： 【發明所屬之技術領域】 本發明係關於一種半導體發光元件；特別是有關於一 種具調變摻雜能障層（modulation-doping barrier layers)之 多重量子井結構的半導體發光元件。 【先前技術】 光通訊系統係使用光信號於光纖中以高速傳輸資 料。光通訊系統不會受到電磁波的干擾，並且使用於光通 訊系統的玻璃光學纖維具有重量輕、低價格及寬頻操作能 力。因此，隨著對通訊能力的要求不斷地增加，以光信號 傳輸大量資料的光通訊系統已愈來愈受歡迎。光放大器 (optical amplifier)係光通訊系統中一個重要的元件，其可 設於光通訊系統的來源端（source end)，以供做功率放大器 或者設於光信號傳輸路徑，以供做傳輸線放大器（Une amplifier)，或者設於光通訊系統的接收端，以供做前置放 大器（preamplifier) 〇 半導體光放大器（Semiconductor Optical Amplifier· SOA)係目前主要使用的一種光放大器，其具有體積小，易 於整合於小元件上等優點。半導體光放大器的結構基本上 相同於半導體雷射結構，不同處係在於半導體雷射兩端的 鏡面以抗反射塗層（antireflection coatings)取代，以構成半 $體光放大器。當光"ί§ 5虎通過半導體光放大器時，該半導 體光放大裔可將该光信號放大。在目前的光纖通訊中，在 長距離的通訊時，信號將會損失而需要被放大，一些應用 中需採用半導體光放大器放大信號，因此，一個具有寬頻 斗寸〖生的半體光放大态將是令人期待的。目前使用的半導^ 1269506 體光放大器多以不同的材料比例組合而成的多重量子井結 構來達成寬頻特性。如第一圖所示，係一種已知的半導體 光放大器結構的截面示意圖，其主要包含一 N型基板 100、一 N 型下侷限層（N type cladding layer) 101、一多重 量子井結構(multiple quantum well structure) 102、一 P 型1269506 IX. Description of the Invention: [Technical Field] The present invention relates to a semiconductor light-emitting element; and more particularly to a semiconductor light-emitting structure having a multi-quantum well structure with modulation-doping barrier layers element. [Prior Art] An optical communication system uses an optical signal to transmit data at a high speed in an optical fiber. Optical communication systems are not subject to electromagnetic interference, and glass optical fibers used in optical communication systems are lightweight, low cost, and broadband operating capability. Therefore, as the demand for communication capabilities continues to increase, optical communication systems that transmit large amounts of data with optical signals have become increasingly popular. An optical amplifier is an important component of an optical communication system, which can be disposed at a source end of an optical communication system for use as a power amplifier or in an optical signal transmission path for a transmission line amplifier ( Une amplifier), or at the receiving end of the optical communication system, is used as a preamplifier. The semiconductor optical amplifier (Semiconductor Optical Amplifier SOA) is currently used mainly as an optical amplifier, which is small in size and easy to integrate. On the advantages of small components. The structure of the semiconductor optical amplifier is substantially the same as that of the semiconductor laser structure, except that the mirror faces at both ends of the semiconductor laser are replaced by antireflection coatings to form a half body optical amplifier. When the light passes through the semiconductor optical amplifier, the semiconductor light amplification can amplify the optical signal. In the current optical fiber communication, in long-distance communication, the signal will be lost and needs to be amplified. In some applications, a semiconductor optical amplifier is required to amplify the signal. Therefore, a half-length optical amplification state with a wide frequency band It is expected. The currently used semiconducting ^1269506 bulk optical amplifiers are multi-quantum well structures that are combined in different material ratios to achieve broadband characteristics. As shown in the first figure, a schematic cross-sectional view of a known semiconductor optical amplifier structure mainly includes an N-type substrate 100, an N-type cladding layer 101, and a multiple quantum well structure ( Multiple quantum well structure) 102, a P type
上侷限層103，一陰極電極i〇4及一陽極電極1〇5。第一 A 圖係第一圖中該多重量子井結構1〇2的截面放大示意圖， 口玄夕重里子井結構102具有兩組不同量化能階的量子井 群。第一組量子井群係由兩個銦〇53鎵〇47砷量子井1〇2a 組成，該兩個銦G.53鎵G.47坤量子井102a係靠近P型上侷 限層胃103。第二組量子井群係由三個銦〇 67鎵〇 33砷〇 磷 =8量子井102bj組成，而該三個銦〇67鎵〇33砷〇72磷〇28 置子井102b係靠近N型下侷限層1〇1。該等量子井l〇2a_b 之門係以姻〇·86叙ο·η石申〇 3填〇 7能障層1〇6隔離。如第 示的半導體光放大器係利用不同的材料組成比例組 井結構’以產生不同的發光波長。此種方式 不斷改變材料組成’材料比例將難以掌握， ，再二，長的不精確’製程上也較為複雜，難以控制。 財’夕重量子井結構中，不 合的機率不_，使 ^子井載子復 大倍率在頻譜：不？波長舍光強度不相同，而導致放 特性有不利㈣ΐ夠—致，進㈣半導體域大器的寬頻 構，種可改善寬頻特性的多重量子井結 【發明内容】 ^ 要目的係長1供一種具調變換雜多重量子井 6 1269506 結構的半導體發光元件，並在/ a 夕旦 (barrier layer)it^f^ ^ 制任一量子㈣發光料，岐善元件整體的^特性 本發明之另-目的係提供一種半導體雷射， 雷射頻寬範圍及特性。 〃 放大月之又目的係提供一種寬頻特性佳的半導體光 壬旦以上所述之目的，本發明提供—種具調變摻雜多 井群的半導體結構，其包括複數組 階The upper limiting layer 103, a cathode electrode i〇4 and an anode electrode 1〇5. The first A diagram is a cross-sectional enlarged view of the multi-quantum well structure 1〇2 in the first figure, and the Xuan Xizhongli sub-well structure 102 has two sets of quantum well groups with different quantized energy levels. The first group of quantum wells consists of two indium 〇53 gallium arsenide 47 arsenic quantum wells 1〇2a, which are close to the p-type upper layer of the stomach 103. The second group of quantum wells consists of three indium 〇67 gallium 〇33 arsenic arsenide=8 quantum wells 102bj, and the three indium 〇67 gallium 〇33 arsenic 〇72 〇28 置28 wells 102b are close to the N type The lower limit layer is 1〇1. The gates of these quantum wells l〇2a_b are separated by the incarnation of the 86 ο · η 〇 〇 〇 〇 〇 〇 〇 〇 能 能 能 能 能 能 能 能 能 能 能 能 能 能The semiconductor optical amplifiers as shown in the above section utilize different material composition ratio well structures to produce different emission wavelengths. This method of changing the material composition 'material ratio will be difficult to master, and second, the long inaccuracy' process is also more complicated and difficult to control. In the structure of the Weighing Well, the probability of discomfort is not _, so that the sub-well carrier is multiplied in the spectrum: no? The intensity of the wavelength is not the same, which leads to the unfavorable discharge characteristics. (4) — — , 进 进 进 进 四 四 四 四 四 四 四 四 四 四 四 四 四 四 四 四 四 四 四 四 四 四 多重 多重 多重 多重 多重 多重 多重 多重 多重 多重 多重 多重 多重 多重 多重 多重 多重 多重The semiconductor light-emitting element of the heterogeneous multi-quantum well 6 1269506 structure is modulated, and any quantum (four) luminescent material is fabricated in the /a hurricane layer, which is a further feature of the present invention. It provides a semiconductor laser, wide range and characteristics of the RF.放大 Amplifying the Month is also intended to provide a semiconductor light having excellent broadband characteristics. The present invention provides a semiconductor structure having a modulated doped multi-well group including complex array orders.
量子井群及複數層輯層；每—該量子料具有至 ^井層’該等量子井群之料量子井層的材料組成比例相 同’但不同1子井群的量子井層厚度不相等，而同一量子 井群的量子井層厚度㈣；鱗能障層係_ J :=ί互相間的結構’該等能障層具有推雜濃度“ 本發明係於該等能障層中進行調變柊雜 光V員兔範圍更大’頻丸特性更佳。 【實施方式】 本發明提供-種具調變摻雜多重量子井（Μ Quantum Well, MQW)結構的半導體發光元件， 且 變摻雜的多重量子井結構，可產生發光強度較曰為一致的 不同發光波長，以增加發光頻寬，進而提供更佳的寬頻 性：前，具調變摻雜多重量子井結構係具有材料組成比例 相同但覓度不同的多個量子井，並且該等量子井 wells)與能障層（barrier layers)形成交互相間的結構。本發 7 1269506 明的半導體發光元件的不同發光波長係來自不同寬度但材 料組成比例相同的該等量子井，其中寬度較窄的量子井能 里較南’發光強度較弱’見度較見的量子井能量較低，發 光強度較強。本發明係在於發光強度較弱的該等量子井周 圍的能障層進行調變摻雜(modulation-doping)，加入p型摻 質’以提高能量較高的該等量子井的發光強度，進而使不 同能量的該等量子井的發光強度趨於一致，達到更寬頻的 特性。 總括言之，本發明係利用調變摻雜於具有多個不同發 光波長的非對稱多重量子井結構中的能障層，達到控制任 一量子井的發光強度，以提升整體的發光特性。 本發明之目的及諸多優點藉由以下具體實施例之詳細 說明，並參照所附圖式，將趨於明瞭。 再者，以下對本發明在具調變摻雜多重量子井結構的半 導體發光元件的描述，並不包括該半導體發光元件之完整 結構。本發明所沿用的現有技藝’在此僅做重點式的引用， 以助本發明的闡述。並且下述内文中相關圖式並未依比例 φ 繪製，其作用僅在表現本發明的結構特徵。 第二圖係本發明具調變摻雜多重量子井結構的半導 體發光元件的一具體實施例的截面示意圖，其包括一 N型 基板200，例如N型神化鎵(GaAs)基板；一厚度約1〇〇毫 微米（nm)的N型下偈限層（N type lower cladding — layer)201，係位於該N型基板200上；一具有調變摻雜多 重量子井結構的主動層202，係位於該N型下侷限層201 上，一厚度約100宅微米的P型上偈限層（p type upper cladding layer)203，係位於該主動層201上；一陰極電極 204係位於該N型基板200下方，該陰極電極204係電性 8 1269506 連接至-直流電源供應器的陰極；及一陽 於該P型上侷限層203的上方τ ^ " 係位 接至-室产二。 電極205係電性連 接至置々丨L包源供應器的陽極。 疋 f二圖的半導體發光元件中該絲層202 的刖述/、调交摻雜多重量子井結構的截面放大示意圖；豆a quantum well group and a plurality of layers; each of the quantum materials has a material composition ratio of the quantum well layers of the quantum well groups to the same level 'but the quantum well layers of different 1 sub-well groups are not equal in thickness, The thickness of the quantum well layer of the same quantum well group (4); the scale energy barrier layer _ J := ί mutual structure 'the energy barrier layers have the push concentration "The present invention is modulated in the energy barrier layers The present invention provides a semiconductor light-emitting device having a modulated quantum doped multi-quantum well (Μ Quantum Well, MQW) structure, and is doped with a variable size. The multiple quantum well structure can produce different illuminating wavelengths with uniform illuminance to increase the illuminating bandwidth, thereby providing better broadband: before, the modulated quantum doped multi-quantum well structure has the same material composition ratio However, a plurality of quantum wells having different twists, and the quantum wells) and the barrier layers form an inter-phase structure. The different light-emitting wavelengths of the semiconductor light-emitting elements of the present invention are from different widths but materials. The quantum wells with the same composition ratio, wherein the quantum wells with narrow widths are less dense than the south, and the quantum wells have lower energy and stronger luminescence intensity. The invention is based on weaker luminescence intensity. The energy barrier layers around the quantum wells are modulated-doping, and the p-type dopants are added to increase the luminous intensity of the higher-energy quantum wells, thereby enabling the quantum wells of different energies. The illuminating intensity tends to be uniform and achieves a wider frequency characteristic. In summary, the present invention utilizes an energy barrier layer modulated in an asymmetric multiple quantum well structure having a plurality of different illuminating wavelengths to control any quantum. The illuminating intensity of the well is used to enhance the overall illuminating properties. The objects and many advantages of the present invention will become apparent from the following detailed description of the embodiments of the present invention. The description of the semiconductor light-emitting element of the doped multi-quantum well structure does not include the complete structure of the semiconductor light-emitting element. The prior art of the present invention is only focused here. Reference is made to the description of the present invention, and the related drawings in the following texts are not drawn to scale φ, and their functions are only to show the structural features of the present invention. The second figure is a modulated doping multiple quantum of the present invention. A schematic cross-sectional view of a specific embodiment of a well-structured semiconductor light-emitting device comprising an N-type substrate 200, such as an N-type gallium arsenide (GaAs) substrate; and an N-type lower limit having a thickness of about 1 nanometer (nm) A layer (N type lower cladding — layer) 201 is disposed on the N-type substrate 200. An active layer 202 having a modulated doped multiple quantum well structure is disposed on the N-type lower confinement layer 201 and has a thickness of about 100. A p-type upper cladding layer 203 is disposed on the active layer 201; a cathode electrode 204 is located under the N-type substrate 200, and the cathode electrode 204 is electrically connected to the - the cathode of the DC power supply; and a yang above the p-type upper confinement layer 203 ^ " the line is connected to the - room production two. The electrode 205 is electrically connected to the anode of the L-package source supply.疋 fDifferent diagram of the wire layer 202 in the semiconductor light-emitting element of the second diagram, and a cross-sectional enlarged view of the doped multi-quantum well structure;
，中，具調變摻雜多重量子井結構係包括三組量子井群，ς 等量子井群具有不同的量化能階El，Ε2及Ε3，其^ Ε1<Ε2<Ε3。第一組量子井群靠近該ρ型上侷限層2〇3，係 具有兩個厚度約1〇〇毫微米（nm)的砷化鎵〇 _銦 o.532(In〇.532Ga〇.468As)量子井層 202a，具有能階 E1。第二組 量子井群係位於該第一組量子井群下方，係具有兩個厚度 約70毫微米（nm)的砷化鎵0 468銦〇 532(in〇 532Ga〇 468As)量子 井層202b，具有能階E2。第三組量子井群靠近該N型下 侷限層201，係具有兩個厚度約40毫微米（nm)的砷化鎵 0.468 銦 o.532(In〇.532Ga〇.468As)量子井層 202c，具有能階 E3。 該等量子井層202a-c之間係以一厚度約50毫微米的石申化 姻 0.528 嫁 0.257 銘 0.215(InQ.528Ga0.257Al〇.2l5As)能障層 206 隔 離，但該多重量子井結構分別靠近該P型上侷限層203與 該N型下侷限層201的該等砷化銦〇 528鎵Q.257鋁 0.215(In〇.528Ga〇 257Al〇.215As)能障層 206 厚度為 500 宅微米。 參第三圖，係該具調變摻雜多重量子井結構的能階示意 圖，在此一具體實施例中，本發明係於具有能階E2的該 等量子井202b周圍的該等能障層206進行調變摻雜 (modulation-doping)，加入P型摻質，例如加入換雜濃度約 lx 1018 ions/cm3的鈹原子(Be)，以調控該等量子井202b的 發光強度。在本發明中，亦可使用其它P型摻質進行調變 摻雜，例如鋅(Zn)或碳(C)。 1269506 第四圖係未加入p型調變摻質的第二圖所示半導體發 光元件的電激發光頻譜圖，可明顯看出，不同能階的該等 量子井202a，202b，202c具有明顯差異的發光強度，能量愈 高的量子井，發光強度愈弱，而該半導體發光元件所能提 供頻譜寬度係為1370埃(人）。第五圖係加入p型調變摻質 的第二圖所示半導體發光元件的電激發光頻譜圖，可看出 能量較高的該等量子井202b周圍的該等能障層206加入P 型摻質後，該等量子井202b的發光強度明顯提高，趨於與 具較低能階E1的該等量子井2〇2&的發光強度一致，並且 該半導體發光元件的頻譜寬度增加為173〇埃(A)。因此， 本發明第二圖所示具調變摻雜多重量子井結構的半導體發 光元件即可提供特性更佳的頻寬範圍。 本發明具調變摻雜多重量子井結構的半導體發光元件 可提供更大的頻寬範圍及更佳的寬頻特性，可應用於半導 體雷射及半導體光放大器等半導體光通訊元件。 上述之具體實施例係為本案之較佳實施例之一，並非 本案之全貌。在實際應用上，該等量子井群的材質可以加 以變只要該等量子井群的材料組成比例相同，而控制 該等量f井群的個別厚度，以使之具有不同量化能階即 可。該等量子井群的排列次序也不受限於上述，可以加以 變化。再者，本案具調變摻雜多重量子井結構並不侷限於 使用f組量子井群，可視需要決定量子井群的數目，只要 該等量子井群具有不同的量化能階即可。並且每一個量子 井群的量子井數目也可視情況加以改變，其可由一個、二 ，、、二個、甚至多個量子井組成，並不會因此影響本案所 欲達成的功效。本發明可視情況對各能障層進行摻質濃度 不-的調變摻雜，以獲得所欲具良好品質的寬頻特性。又 1269506 故以上所述僅為本發明之具體實施例而已，並非用以 限定本發明之申請專利範圍；凡其它未脫離本發明所揭示 之精神下所完成之等效改變或修飾，均應包含在下述之申 請專利範圍内。The medium-duplex multi-quantum well structure with modulation and modulation includes three sets of quantum well groups, and the quantum well groups such as ς have different quantified energy levels E1, Ε2 and Ε3, which are Ε1<Ε2<Ε3. The first set of quantum well groups is adjacent to the p-type upper confinement layer 2〇3, having two gallium arsenide bismuthium-indium o.532 (In〇.532Ga〇.468As) having a thickness of about 1 〇〇 nanometer (nm). The quantum well layer 202a has an energy level E1. A second set of quantum well groups is located below the first set of quantum wells, having two gallium arsenide 0 468 indium 532 (in 〇 532Ga 〇 468As) quantum well layers 202b having a thickness of about 70 nanometers (nm). Has energy level E2. The third group of quantum wells is adjacent to the N-type lower confinement layer 201, and has two gallium arsenide 0.468 indium o.532 (In〇.532Ga〇.468As) quantum well layers 202c having a thickness of about 40 nanometers (nm). Has energy level E3. The quantum well layers 202a-c are isolated by a barrier of a thickness of about 50 nanometers, 0.528, 0.257, 0.215, and 0.215 (InQ.528Ga0.257Al〇.2l5As), but the multiple quantum well structure The indium arsenide arsenide 528 gallium Q.257 aluminum 0.215 (In〇.528Ga〇257Al〇.215As) barrier layer 206 is adjacent to the P-type upper confinement layer 203 and the N-type lower confinement layer 201, respectively, and has a thickness of 500 houses. Micron. Referring to the third figure, the energy level diagram of the modulated multi-quantum well structure is modulated. In this embodiment, the present invention is applied to the energy barrier layers around the quantum wells 202b having the energy level E2. 206 is subjected to modulation-doping, and a P-type dopant is added, for example, a germanium atom (Be) having a concentration of about 1×10 18 ions/cm 3 is added to regulate the luminous intensity of the quantum well 202b. In the present invention, other P-type dopants may also be used for the modulation doping, such as zinc (Zn) or carbon (C). 1269506 The fourth figure is the electric excitation spectrum of the semiconductor light-emitting element shown in the second figure without the p-type modulation dopant. It can be clearly seen that the quantum wells 202a, 202b, and 202c of different energy levels have significant differences. The luminous intensity, the higher the energy of the quantum well, the weaker the luminous intensity, and the semiconductor light-emitting element can provide a spectral width of 1370 angstroms (person). The fifth figure is an electric excitation spectrum of the semiconductor light-emitting element shown in the second figure in which the p-type modulation dopant is added. It can be seen that the energy barriers 206 around the quantum wells 202b having higher energy are added to the P-type. After doping, the luminescence intensity of the quantum wells 202b is significantly improved, tending to be consistent with the luminescence intensity of the quantum wells 2〇2& having a lower energy level E1, and the spectral width of the semiconductor illuminating element is increased to 173 〇 Egypt (A). Therefore, the semiconductor light-emitting element having the modulated doping multiple quantum well structure shown in the second figure of the present invention can provide a wider range of characteristics. The semiconductor light-emitting device with modulated modulated multi-quantum well structure can provide a wider bandwidth range and better broadband characteristics, and can be applied to semiconductor optical communication components such as semiconductor lasers and semiconductor optical amplifiers. The above specific embodiments are one of the preferred embodiments of the present invention and are not a complete view of the present invention. In practical applications, the materials of the quantum well groups may be changed as long as the material composition ratios of the quantum well groups are the same, and the individual thicknesses of the equal-number f well groups are controlled so as to have different quantization levels. The order in which the quantum well groups are arranged is also not limited to the above and can be varied. Furthermore, the variable-doped multi-quantum well structure in this case is not limited to the use of f-group quantum well groups, and the number of quantum well groups can be determined as needed, as long as the quantum well groups have different quantized energy levels. And the number of quantum wells in each quantum well group can also be changed according to the situation. It can be composed of one, two, two, or even multiple quantum wells, and will not affect the effect that the case is intended to achieve. According to the present invention, the energy barrier layers may be subjected to modulation doping with a non-doping density to obtain a broadband characteristic of good quality. The above description is only a specific embodiment of the present invention, and is not intended to limit the scope of the present invention; all other equivalent changes or modifications which are not departing from the spirit of the present invention should be included. It is within the scope of the following patent application.
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【圖式簡單說明J 第-圖係-已知的半導體光放大器的截面示意圖，· 第一 A圖係第一圖之半導體光放大器的多重量子井 結構的截面放大示意圖； 第二圖係本發明具調變摻雜多重量子井結構的半導 體發光元件的截面示意圖； ^ 第二A圖係第二圖具調變摻雜多重量子井結構的截 面放大示意圖； 第三圖係第二A圖具調變摻雜多重量子井結構的能 階不意圖， 第四圖係第二A圖未加入p型摻質的多重量子井結構 的電激發光頻譜圖；及 ' 第五圖係第二A圖加入p型摻質的多重量子井結構的 電激發光頻譜圖。 主要部份之代表符號： 100…-N型基板 1〇1…型下侷限層 • 1〇2…-多重量子井結構102a…-銦〇.53鎵0.47珅量子井 102b…-銦0.67鎵0.33石申0·72碟〇·28量子井 103----Ρ型上侷限層 104—陰極電極 1〇5——陽極電極 200——Ν型基板 2〇1…-Ν型下侷限層 202—主動層 202a，202b，202c—珅化鎵0·468銦〇 532量子井層 203…-Ρ型上侷限層204——陰極電極 205-…陽極電極206——砷化銦〇 52^f() 257鋁〇215能障層 12BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional view of a semiconductor optical amplifier of a semiconductor optical amplifier of the first embodiment, and FIG. 2 is a cross-sectional enlarged view of a multiple quantum well structure of a semiconductor optical amplifier of the first embodiment; A schematic cross-sectional view of a semiconductor light-emitting device having a modulated doped multi-quantum well structure; ^ A second figure is a cross-sectional enlarged view of a modulated multi-quantum well structure with modulated doping; the third figure is a second A-pattern The energy level of the multi-quantum well structure of the doped multi-quantum well is not intended. The fourth picture is the electro-excitation spectrum of the multi-quantum well structure without the p-type dopant added in the second A diagram; and the fifth figure is the second A picture. Electroluminescence spectrum of a multi-quantum well structure with p-type dopants. Representative symbols of the main parts: 100...-N type substrate 1〇1... type lower layer • 1〇2...-multiple quantum well structure 102a...-indium 〇.53 gallium 0.47珅 quantum well 102b...-indium 0.67 gallium 0.33 Shishen 0·72Disc 〇·28 Quantum Well 103----Ρ Upper Limit Layer 104—Cathode Electrode 1〇5——Anode Electrode 200——Ν-type Substrate 2〇1...-ΝType Lower Limit Layer 202— Active layer 202a, 202b, 202c - gallium antimonide 0 · 468 indium germanium 532 quantum well layer 203 ... - Ρ type upper confinement layer 204 - cathode electrode 205 - ... anode electrode 206 - indium arsenide ^ 52 ^ f () 257 aluminum 〇215 barrier layer 12