TWI233212B - Red light emitting device and method for preparing the same - Google Patents
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I233212 玟、發明說明: 【發明所屬之技術領域】 本發明係關於一種紅光發光元件及其製備方法,特別係 關於一具有含矽發光薄膜之紅光發光元件及其製備方法。 【先前技術】 西元2000年以來,可見光發光二極體之技術開發主要著 重於提升發光亮度與效率。自1968年美國孟山都 (Monsanto)、惠普(HP)等公司相繼推出磷砷化鎵/砷化鎵 (GaAsP/GaAs)紅光發光^一極體商品後,迄今已有36年歷 史。1973年石油危機發生後,日本基於對能源消耗之重視, 研發出耗電低、壽命長的磷化鎵(GaP)紅光發光二極體而開 始進入可見光發光二極體市場。現階段,光電元件(特別是 發光元件)之製作主要是採用磊晶技術,並使用具有直接能 隙(Direct band-gap)之III-V族或Π·νι族等元素作為原料。 自1947年發明電晶體之後,矽材料在積體電路產業一直 就扮演著十分重要的角色。依據摩爾定律(M〇〇re,s Law)之預 測,約每隔18個月左右的時間,積體電路之元件尺寸將縮 減為其原纟的一半。#爾定律主要的依據是新技術的不斷 創新以及潛在應用之開發等條件下所導致的結果,而矽材 料就是這個快速進展的一重要基石。經過多年的發展,石夕 材料應用在積體電路之製程技術可說是最完整也是成本最 低廉的,因此若能將矽材料進一步開發成發光元件,便可 具體地整合發光元件與大型積體電路(VLSI)。 石夕材料(IV族元素)在室溫下為一個無效率的發光源,主I233212 (1) Description of the invention: [Technical field to which the invention belongs] The present invention relates to a red light emitting element and a method for preparing the same, and more particularly to a red light emitting element having a silicon-containing light emitting film and a method for preparing the same. [Previous technology] Since 2000 AD, the technology development of visible light emitting diodes has mainly focused on improving the brightness and efficiency of light emission. Since Monsanto, Hewlett-Packard and other companies in the United States successively introduced gallium phosphorous arsenide / gallium arsenide (GaAsP / GaAs) red light-emitting monopolar products in 1968, it has a 36-year history. After the oil crisis in 1973, Japan, based on its emphasis on energy consumption, developed a gallium phosphide (GaP) red light emitting diode with low power consumption and long life, and began to enter the visible light emitting diode market. At this stage, the production of optoelectronic elements (especially light-emitting elements) is mainly based on epitaxial technology, and uses elements such as III-V or Π · νι with direct band-gap as raw materials. Since the invention of the transistor in 1947, silicon has always played a very important role in the integrated circuit industry. According to Moore's Law's prediction, the component size of integrated circuits will be reduced to half of its original size about every 18 months. The # 1 law is mainly based on the results of continuous innovation of new technologies and the development of potential applications, and silicon materials are an important cornerstone of this rapid progress. After years of development, the process technology of Shi Xi materials applied to integrated circuits can be said to be the most complete and the lowest cost. Therefore, if silicon materials can be further developed into light-emitting elements, light-emitting elements can be specifically integrated with large-scale integrated circuits. Circuit (VLSI). Shi Xi material (Group IV element) is an inefficient light source at room temperature.
H:\HU\HYG\核能所 \92835\92835.DOC 1233212 要的原因在於它是屬於間接能隙(Indirect band-gap)材料,其光 輻射重合率(Radiative recombination rate)甚低,且内部量子發光 效率(Internal quantum efficiency)僅約為 1 (Γ6 至 1 〇-7,以致於一直 都被排除在作為發光源之角色外。因此,矽材料在光電產 業之應用目前則僅侷限於在偵檢器、電荷耦合元件(Charge Coupled Device,CCD)陣列式影像感測器與太陽電池等光接收 元件上。 1990年英國人L.T.Canham發現在氩氟酸溶液中,利用 陽極電解矽材料所形成的多孔性矽材料(Porous Si,PSi)可產 生高效率的可見光源(參考:〇&111^1111^.,八091·?]!}^· Lett.,57,1046(1990))。此一重要發明啟動了全球各國研究團隊 紛紛投入矽光源之開發。在2000至2003年之間,世界上 許多學術研究機構與研究人員皆紛紛投入矽基材發光二極 體之開發,而且產生許多進展(參考:Mykola Sopinskyy and Viktoriya Khomchenko, Current Opinion in Solid State and Material Science 7(2003) pp.97-109.)。惟,目前在矽基材發光二極體之研究開發 工作雖然有不錯的進展,但是迄今仍未有任何商業化的發 光二極體等光電產品。 由於多孔性矽材料具有類似海棉狀之組織結構,因此在 發光元件之應用上具有一些重大的缺點。就機械特性而 言,多孔性石夕材料因易碎而不適合整合於標準的半導體製 程之中。另,多孔性矽材料在化學特性上呈現高度的活性, 易於與空氣中氧原子產生化學作用而呈現光電性能退化, 因而難以控制其光電性能隨時間之變化情形。H: \ HU \ HYG \ Nuclear Energy Institute \ 92835 \ 92835.DOC 1233212 The main reason is that it is an indirect band-gap material, its optical radiation recombination rate is very low, and its internal quantum The internal quantum efficiency is only about 1 (Γ6 to 1 0-7), so that it has been excluded from its role as a light source. Therefore, the application of silicon materials in the optoelectronic industry is currently limited to detection. Device, charge-coupled device (Charge Coupled Device, CCD) array image sensor and solar cells and other light-receiving components. In 1990, the British LTCanham discovered that in the argon fluoride acid solution, the porous formed by the anode electrolytic silicon material Porous Si (PSi) materials can generate high-efficiency visible light sources (Reference: 〇 & 111 ^ 1111 ^., 8091 ·?]!} ^ Lett., 57, 1046 (1990)). Important inventions have initiated research teams from all over the world to invest in the development of silicon light sources. Between 2000 and 2003, many academic research institutions and researchers in the world have invested in the development of silicon-based light-emitting diodes. Exhibition (Reference: Mykola Sopinskyy and Viktoriya Khomchenko, Current Opinion in Solid State and Material Science 7 (2003) pp.97-109.). However, although there is good progress in the research and development of silicon-based light-emitting diodes However, so far there have not been any commercial light-emitting diodes and other optoelectronic products. Because porous silicon materials have a sponge-like structure, they have some major shortcomings in the application of light-emitting elements. In terms of mechanical properties Porous stone materials are not suitable for integration into standard semiconductor processes because they are fragile. In addition, porous silicon materials exhibit a high degree of activity in chemical properties, and are prone to chemical reactions with oxygen atoms in the air, which degrades the photoelectric performance. Therefore, it is difficult to control the change of its photoelectric performance with time.
HAHU\HYG\核能所 \92835\92835.DOC 1233212 【發明内容】 本發明之主要目的係提供—種具有切發光薄膜之紅光 發光元件及其製備方法。 為達成上述目的’本發明揭示—種紅練Μ件及其製 備方法。該紅光發光元件包含一具有一上表面及一下表面 之基板、一設置於該上表面之二氧化石夕薄膜、複數個分佈 於該二氧化石夕薄臈中之石夕奈米晶體、一設置於該二氧化石夕 薄膜上之第-歐姆接觸電極以及一設置於該下表面之第二 歐姆接觸電極。該基板可為一 ρ_型石夕基板或一 η·型石夕基 板:而該第-歐姆接觸電極可由氧化姻錫構成。該二氧化 矽薄膜之厚度係介於i至1〇〇〇〇奈米之間且該石夕奈米晶 體之尺寸係介於3至8奈米之間。 该紅光發光it件之另—實施例係包含H _ 該基板上之合金薄膜、一設置於該合金薄膜之局部表面上 2-氧切薄媒、複數個分佈於該二氧切薄膜中之石夕夺 米晶體、一設置於該二氧化石夕薄媒上之第一 極 :及:r於該合金薄膜之局部表面之第二歐姆接觸: 金薄臈係由矽、鎳及鎵構成,該第一歐姆接觸電 二銘基Γ 而縣㈣—石英基板或―三氧化 :: 红光發光元件之製備方法首先在一基 :比⑽薄膜,其中該次當量比氧切薄膜之二二 與矽原子數之比彻丨认1 /冷胰之氧原子數 理製程以驅使c之後’在氧氣環境令進行一熱處 使该次當量比氧切薄財之部分石夕原子結晶HAHU \ HYG \ Nuclear Energy Institute \ 92835 \ 92835.DOC 1233212 [Summary of the invention] The main purpose of the present invention is to provide a red light emitting element with a cut light emitting film and a preparation method thereof. To achieve the above object, the present invention discloses a Honglian M piece and a method for preparing the same. The red light emitting element includes a substrate having an upper surface and a lower surface, a stone dioxide film disposed on the upper surface, a plurality of stone crystals distributed in the stone oxide thin film, and A first ohmic contact electrode disposed on the stone dioxide film and a second ohmic contact electrode disposed on the lower surface. The substrate may be a ρ-type lithium substrate or an η-type lithium substrate: and the -ohmic contact electrode may be made of tin oxide. The thickness of the silicon dioxide film is between i and 1000 nm, and the size of the stone crystal is between 3 and 8 nm. Another embodiment of the red light emitting it includes an alloy thin film on the substrate, a 2-ox-cut thin medium disposed on a partial surface of the alloy thin film, and a plurality of distributed in the diox-cut thin film. Shi Xidiao rice crystal, a first pole arranged on the Shi Di Xi thin medium: and: r a second ohmic contact on a local surface of the alloy thin film: Au thin alloy is composed of silicon, nickel and gallium, The first ohmic contact is two-base Γ, and the method of preparing a sintered quartz substrate or trioxide :: red light-emitting element is firstly a base: ratio thin film, where the second equivalent ratio of the oxygen-cut film is The ratio of silicon atomic numbers is identified. 1 / cold pancreatic oxygen atomic mathematical process to drive c. After a 'hot place in the oxygen environment order to make a part of the stone equivalent of this time equivalent to oxygen cut thin fortune.
H.\HU\HYG\核能所\92835\9283.5 DOC 1233212 形成複數個石夕奈米晶體。接著,在氫氣環境中進行另一熱 處理程序’其處理溫度係介於5〇〇至6〇〇°c之間,且處理時 間係介於1至120分鐘。 該次當量比氧化矽薄膜係以常壓化學氣相沈積製程形成 於該基板上。該常壓化學氣相沈積製程係使用流量比介於 10:1至1:10間之二氣二氫化矽與一氧化二氮,或矽烷與一 氧化二氮為反應氣體。該常壓化學氣相沈積製程之溫度係 介於700至ll〇〇°c之間,且沈積時間係介於1至3〇〇分鐘。 該常壓化學氣相沈積製程係使用氫氣、氮氣或氬氣為輸送 氣體’將反應氣體均勻混合後送入反應室中。 【實施方式】 量子侷限效應(Quantum confinement effect)使材料之能隙間隔 隨著尺寸變小而變寬,因而奈米尺寸之晶體具有不同於一 般大尺寸材料之獨特光電特性。因此,除了利用習知之多 孔性矽材料之外,研究人員亦嘗試藉由在高穩定性的二氧 化石夕薄腺中形成石夕奈米晶體(SiliC〇n nan〇Cr^stal,來製備 5夕光源。 矽奈米晶體之製備方法係先利用化學氣相沈積技術形成 一具有過剩矽原子(Excess of silicon)成份之次當量比氧化矽 (SiOx)薄膜(Sub-stoichiometric silica film),其氧原子數與矽原子 數之比例(X)小於2。隨後進行至少一高溫的退火處理 (Annealing)以驅使兩個不同的金屬相(即矽與二氧化矽)彼此 分離,以同時形成具有秩序(〇rder)的結構之矽奈米晶體與均 質結構(Amorphous)之二氧化矽,其中二氧化矽薄膜係作為矽H. \ HU \ HYG \ Nuclear Energy Research Institute \ 92835 \ 9283.5 DOC 1233212 forms a number of Shixunai crystals. Next, another thermal treatment process is performed in a hydrogen environment, the treatment temperature is between 500 and 600 ° C, and the treatment time is between 1 and 120 minutes. The sub-equivalent-ratio silicon oxide film is formed on the substrate by an atmospheric pressure chemical vapor deposition process. The atmospheric pressure chemical vapor deposition process uses digas silicon dioxide and nitrous oxide, or silane and nitrous oxide as a reaction gas at a flow ratio between 10: 1 and 1:10. The temperature of the atmospheric pressure chemical vapor deposition process is between 700 and 100 ° C, and the deposition time is between 1 and 300 minutes. This atmospheric pressure chemical vapor deposition process uses hydrogen, nitrogen, or argon as the transport gas' to uniformly mix the reaction gases and send them into the reaction chamber. [Embodiment] The quantum confinement effect makes the energy gap interval of the material widen as the size becomes smaller, so nanometer-sized crystals have unique optoelectronic properties that are different from those of ordinary large-sized materials. Therefore, in addition to the use of conventional porous silicon materials, researchers have also attempted to prepare 5 by forming silicon crystalline nanocrystals (SiliCon nan〇Cr ^ stal in high-stability SiO2 thin glands). Evening light source. The method for preparing silicon nanocrystals is to first use chemical vapor deposition technology to form a sub-stoichiometric silica film with excess silicon atoms (Excess of silicon). The ratio of atomic number to silicon atomic number (X) is less than 2. Subsequently, at least one high-temperature annealing treatment (Annealing) is performed to drive two different metal phases (that is, silicon and silicon dioxide) to separate from each other to form an order ( 〇rder) structure of silicon nanocrystals and homogeneous structure (Amorphous) of silicon dioxide, of which the silicon dioxide film is used as silicon
H:\HU\HYG\ 核能所\92835\92835.DOC -10- 1233212 奈米曰曰體寄佰用之母體組織(matrix)。由於二氧化矽材料為 均質結構,因此矽奈米晶體與二氧化矽之間係無應變 (Strain-free)。矽奈米晶體之大小與密度可以藉由薄膜沈積溫 度與退火溫度等工作參數來控制。 另一種矽奈米晶體之製備方法就是採用離子佈植技術。 離子佈植技術是發展多年成熟的技術,已使用在大型半導 體積體電路製程之十。離子佈植技術係將加速的矽離子直 接植入二氧化矽薄膜之中,以於二氧化矽薄膜内之局部區 域形成過剩矽原子。之後,進行退火處理以驅使過剩矽原 子成核結晶以形成寄宿於二氧化矽薄膜(母體組織)中的矽 奈米晶體。 離子佈植技術可藉由調節植入離子的能量與劑量,而在 一特定的局部區域與深度範圍植入所需的過剩矽原子濃度 (Concentration)與分佈輪廓(Pr〇flle)。再者,在離子佈植過程中 亦形成出δ午多結構性的缺陷(Structurai de免cts),而這些結構性 缺可降低原子擴散之活性能(Activation energy of,使 得執行金屬相分離所需之退火處理的溫度亦隨之相對的降 低。然而,相較於化學氣相沈積製程,因離子佈植技術形 成過剩矽原子濃度所需時間太長以致於不適合應用於製備 發光元件之發光薄膜。 廣泛使用於半導體製程之化學氣相沈積法(Chemical Vap0r Deposition,CVD)依據工作溫度範圍(從i 〇〇至i 〇〇〇t:)與工作 壓力範圍(從大氣壓力至7Pa等變化)可分為常壓化學氣相 沈積法(APCVD)、低壓化學氣相沈積法(LpcVD)與電漿強H: \ HU \ HYG \ Nuclear Energy Research Institute \ 92835 \ 92835.DOC -10- 1233212 Nano matrix is used as the matrix of the body. Because the silicon dioxide material has a homogeneous structure, there is no strain between the silicon nanocrystals and the silicon dioxide (Strain-free). The size and density of silicon nanocrystals can be controlled by working parameters such as film deposition temperature and annealing temperature. Another method for preparing silicon nanocrystals is ion implantation. Ion implantation technology is a mature technology that has been developed for many years. It has been used in tenth of the large-scale semiconductor volume circuit manufacturing process. Ion implantation technology implants accelerated silicon ions directly into the silicon dioxide film to form excess silicon atoms in a local area within the silicon dioxide film. After that, an annealing process is performed to drive the excess silicon atoms to nucleate and crystallize to form silicon nanocrystals hosted in a silicon dioxide film (parent structure). Ion implantation technology can adjust the concentration and distribution of excess silicon atoms (PrOflle) required for implantation in a specific local area and depth range by adjusting the energy and dose of implanted ions. In addition, delta structural defects (structurai de cts) are also formed during the ion implantation process, and these structural defects can reduce the activation energy of atomic diffusion, making it necessary to perform metal phase separation. The temperature of the annealing treatment is also relatively lowered. However, compared with the chemical vapor deposition process, the time required to form the excess silicon atom concentration due to the ion implantation technology is too long to be suitable for the light-emitting film of the light-emitting device. Chemical Vapor Deposition (CVD), which is widely used in semiconductor manufacturing processes, can be divided according to the operating temperature range (from 〇OO to 〇〇t :) and the working pressure range (from atmospheric pressure to 7Pa, etc.). For atmospheric pressure chemical vapor deposition (APCVD), low pressure chemical vapor deposition (LpcVD) and plasma strength
H:\HU\HYG\ 核能所\92835\92835.DOC -11 - 1233212 化化學氣相沈積法(PECVD)等三種。相較於離子佈植技 術’化學氣相沈積法具有可精準的控制沈積薄膜之組成與 結構、均勻且快速的沈積速率、高產量及低製作成本等優 點。 低壓化學氣相沈積法與電漿強化化學氣相沈積法等低溫 沈積製程所形成的含矽薄膜之金相結構較為鬆散,且具有 較多會抑制結晶成長之結構性缺陷與雜質。本發明係選擇 使用高溫之常壓化學氣相沈積製程來製備發光二極體之含 矽發光薄膜。由於高溫環境下製備之含矽發光薄膜具有較 少的結構性缺陷及雜質,且複雜的矽_氮·氧(si_N-〇)複合物 可形成高緻密性與高密度分佈之矽奈米晶體。如此,矽奈 米晶體之螢光光譜具有高清晰度、高亮度及較窄的光譜半 寬度。 圖1係一常壓化學氣相沈積裝置100之示意圖。如圖i 所示,该常壓化學氣相沈積裝置100包含一反應室、一 設置於該反應室1〇外圍之高頻振盪電源12、一設置於該反 應至10中之石墨塊14、一進氣岐管16以及一出氣岐管18。 石墨塊14係用以承載欲進行薄膜沈積之基板22。較佳地, 石墨塊14本身已事先沈積一層由碳化矽及二氧化矽構成之 薄膜15,以避免氧分子對石墨塊14之侵蝕。 圖2至圖4例示本發明紅光發光二極體之製備方法。本 發明製備發光二極體50時首先將基板22置放於反應室ι〇 之石墨塊14上,再利用高頻振盪電源12將石墨塊14加熱 到沈積溫度TD。該基板22可為一 p_型石夕基板或一卜型:H: \ HU \ HYG \ Nuclear Energy Institute \ 92835 \ 92835.DOC -11-1233212 chemical vapor deposition (PECVD) and other three. Compared with the ion implantation technology, the chemical vapor deposition method has the advantages of accurately controlling the composition and structure of the deposited film, uniform and fast deposition rate, high yield, and low production cost. The metallographic structure of the silicon-containing thin film formed by low-temperature deposition processes such as low-pressure chemical vapor deposition and plasma-enhanced chemical vapor deposition is relatively loose, and it has many structural defects and impurities that inhibit crystal growth. The present invention chooses to use a high-temperature atmospheric pressure chemical vapor deposition process to prepare a silicon-containing light-emitting film of a light-emitting diode. Because the silicon-containing light-emitting film prepared under high temperature environment has fewer structural defects and impurities, and the complex silicon-nitrogen-oxygen (si_N-〇) complex can form silicon nanocrystals with high density and high density distribution. In this way, the fluorescence spectrum of silicon nanocrystals has high definition, high brightness, and a narrow spectral half width. FIG. 1 is a schematic diagram of an atmospheric pressure chemical vapor deposition apparatus 100. As shown in FIG. I, the atmospheric pressure chemical vapor deposition device 100 includes a reaction chamber, a high-frequency oscillating power source 12 disposed outside the reaction chamber 10, a graphite block 14 disposed in the reaction chamber 10, a An intake manifold 16 and an exhaust manifold 18. The graphite block 14 is used to carry a substrate 22 for thin film deposition. Preferably, the graphite block 14 itself has been previously deposited with a thin film 15 composed of silicon carbide and silicon dioxide to prevent the graphite block 14 from being attacked by oxygen molecules. 2 to 4 illustrate a method for preparing the red light emitting diode of the present invention. In preparing the light-emitting diode 50 according to the present invention, a substrate 22 is first placed on a graphite block 14 in a reaction chamber ιo, and then the graphite block 14 is heated to a deposition temperature TD by a high-frequency oscillation power source 12. The substrate 22 may be a p-type Shixi substrate or a Bu type:
H:\HU\HYGVf|[能所\92835\92835.DOC •12- 1233212 基板,且具有一上表面23A及一下表面23B。之後,藉由 運送氣體(可選用氫氣、氬氣或氮氣)11將一定摩爾數或體 積比例之反應氣體17經由進氣岐管16均勻混合後送入反 應室10中。反應氣體17可為二氣二氫化矽(SiH2Cl2)與一 氧化二氮(N20)之混合氣體,且二者之流量比或體積比例係 介於1 : 10至10 : 1之間。此外,反應氣體17亦可為或矽 烷(SiHd與NzO之混合氣體,且二者之流量比或體積比例 係介於1 : 10至10 : 1之間。 將該反應室10維持在沈積溫度Td —預定時間tD,以形 成一具有過剩矽原子之次當量比氧化矽(SiOx)薄膜20於基 板22之上表面23A上’其氧原子數與妙原子數之比例(x) 小於2。其它反應副產物19,例如氮氣(N2)與氣化氩(HC1) 等氣體則經由排氣岐管18連續排出。之後,輸入一含氧氣 體至反應室10之中以形成一含氧環境,並將反應室1〇之 溫度升高至一處理溫度TP且保持一預定時間tp以進行一熱 處理程序。該含氧氣體可為氧氣、臭氧(〇3)或其它在處理 溫度Tp下可熱分解產生氧原子之分子。 δ亥反應至10之環境將驅使該次當量比氧化石夕薄膜2 〇内 之過剩石夕原子進行晶體成長及熟化等反應程序,以將該次 當量比氧化矽薄膜20轉化形成一具有矽奈米晶體24之二 氧化石夕薄膜26。該二氧化矽薄膜26之厚度係介於1至ι〇〇〇〇 奈米之間,而該矽奈米晶體24之尺寸係介於3至8奈米之 間。在含氧環境中,矽奈米晶體24與二氧化矽母體組織間 矽-氮-氧(Si-N_〇)懸掛鍵螢光中心,其中部份氮懸掛鍵被氧 H:\HU\HYG\ 核能所\92835\92835.DOC -13- 1233212 原子取代,形成紅光螢光中心。 接著’通入氫氣至反應室10之中,並將反應室之溫 度升咼至風鈍化溫度TPH且保持一預定時間tpH,以於一 氫氣環境中進行矽奈米晶體24之表面鈍化程序。熱處理程 序及表面鈍化程序將該次當量比氧化矽薄膜2〇轉化成一具 有矽奈米晶體24之二氧化矽薄膜26。該二氧化矽薄膜26 係作為石夕奈米晶體24寄宿用之母體組織。 清參考圖4,在二氧化石夕薄膜26上形成一層由氧化姻锡 (indium tin oxide,IT0)構成之透明歐姆接觸電極28,及在基板 22之下表面23Β形成一歐姆接觸電極3〇以完成該發光二 極艘50。若在透明歐姆接觸電極28上施加正電壓並在歐姆 接觸電極30上施加負電壓’該發光二極體5()將由電流激 發而發射出紅光40。 圖5例示本發明之沈積程序、熱處理程序及表面鈍化程 序之操作溫度及時間。如圖5所示,沈積溫度介於· °c至iioo°c之間,且沈積時間tD係介於i至3〇〇分鐘。熱 處理程序之溫度TP係介於8〇〇至13〇〇。。之間,且處理時間 tP係介於丨至遍分鐘。表面純化程序之溫度ΤρΗ係介於 500至60(TC,工作時間tpH係介於^ΐ2〇分鐘。 圖6係本發明之二氧化石夕薄膜%之石夕奈米晶體以的光 激螢光卿—讎_ ’ PL)光譜圖。該光激螢光光譜圖係以 氬氣雷射光束(波長為488奈米)直接照射該二氧化㈣膜 26’再量測财奈米晶體24發出之光激螢光。如圖6所_、 該二氧切薄膜26内…奈米晶體“所發出之光:榮H: \ HU \ HYGVf | [能 所 \ 92835 \ 92835.DOC • 12-1233212 substrate, and has an upper surface 23A and a lower surface 23B. Thereafter, a certain number of moles or a volume ratio of the reaction gas 17 is uniformly mixed through the intake manifold 16 by the transport gas (optionally hydrogen, argon or nitrogen) 11 and then sent to the reaction chamber 10. The reaction gas 17 may be a mixed gas of silicon dihydrogen hydride (SiH2Cl2) and nitrous oxide (N20), and the flow ratio or volume ratio of the two is between 1:10 and 10: 1. In addition, the reaction gas 17 may be a mixed gas of silane (SiHd and NzO), and the flow ratio or volume ratio of the two is between 1: 10 and 10: 1. The reaction chamber 10 is maintained at a deposition temperature Td —Predetermined time tD to form a silicon oxide (SiOx) film 20 with a second equivalent of excess silicon atoms on the upper surface 23A of the substrate 22, whose ratio (x) of the number of oxygen atoms to the number of wonderful atoms is less than 2. Other reactions By-products 19, such as nitrogen (N2) and gasified argon (HC1), are continuously discharged through the exhaust manifold 18. After that, an oxygen-containing gas is input into the reaction chamber 10 to form an oxygen-containing environment, and The temperature of the reaction chamber 10 is increased to a processing temperature TP and maintained for a predetermined time tp to perform a heat treatment process. The oxygen-containing gas may be oxygen, ozone (〇3), or other thermal decomposition at the processing temperature Tp to generate oxygen The molecule of the atom. The environment where the δH reaction reaches 10 will drive the excess equivalent atomic oxide in the second equivalent ratio oxide film to 200 to undergo crystal growth and aging processes, so as to transform the second equivalent ratio silicon oxide film 20 to form One with silicon nano crystal 2 4 SiO 2 film 26. The thickness of the silicon dioxide film 26 is between 1 and 100,000 nanometers, and the size of the silicon nanocrystal 24 is between 3 and 8 nanometers. In an oxygen-containing environment, the fluorescent center of the silicon-nitrogen-oxygen (Si-N_〇) dangling bond between the silicon nanocrystal 24 and the silicon dioxide parent tissue, some of which are suspended by oxygen H: \ HU \ HYG \ Nuclear Energy Institute \ 92835 \ 92835.DOC -13- 1233212 Atoms are replaced to form a red fluorescent center. Then, hydrogen gas is introduced into the reaction chamber 10, and the temperature of the reaction chamber is raised to the wind passivation temperature TPH. And maintain a predetermined time tpH to perform the surface passivation process of the silicon nanocrystal 24 in a hydrogen environment. The heat treatment process and the surface passivation process convert the second equivalent silicon oxide film 20 into a silicon nanocrystal 24bis. A silicon oxide film 26. The silicon dioxide film 26 is used as a host structure for the boarding of the shixi nanocrystal 24. Referring to FIG. 4, a layer of indium tin oxide (IT0) ) Constitutes a transparent ohmic contact electrode 28, and forms a ohm on the lower surface 23B of the substrate 22. Contact electrode 30 to complete the light emitting diode vessel 50. If a positive voltage is applied to the transparent ohmic contact electrode 28 and a negative voltage is applied to the ohmic contact electrode 30, the light emitting diode 5 () will be excited by the current and emit red Light 40. Fig. 5 illustrates the operating temperature and time of the deposition process, heat treatment process and surface passivation process of the present invention. As shown in Fig. 5, the deposition temperature is between · ° c to iioo ° c, and the deposition time tD is introduced In the range of i to 300 minutes, the temperature TP of the heat treatment process is between 800 and 1300 ..., and the treatment time tP is in the range of 丨 to 1 minute. The temperature Tρ of the surface purification process is between 500 and 60 ° C., and the working time tpH is between 20 minutes and 20 minutes. FIG. 6 is a light-excitation fluorescence of the crystalline silicon dioxide film of the present invention. Qing— 雠 _ 'PL) spectrum. The photo-induced fluorescence spectrum is obtained by directly irradiating the hafnium dioxide film 26 'with an argon laser beam (wavelength of 488 nanometers), and then measuring the light-induced fluorescence emitted by the nano-crystal 24. As shown in Figure 6_, the light emitted from the nano-crystalline film 26 in the dioxy-cut film 26: Rong
H:\HU\HYG\核能所 \92835\92835.DOC -14- 1233212 2的波長係介於_纟85G奈米之間,波峯波長係在650 至750奈米之間,為可見光之紅光。 圖7例示本發明第二實施例之發光二極體7〇。如圖”斤 不,該發光二極體70包含一基板33、-設置於該基板33 ^之合金薄膜60、一設置於該合金薄膜6〇之局部表面之二 ^化石夕薄膜26、-設置於該二氧化發薄冑%上之透明電極 X置於该合金薄膜6〇之局部表面之歐姆接觸電極 64。該二氧化矽薄膜26係以前述之方法製備,因而具有可 發出紅光之矽奈米晶體24。該合金薄膜6〇係由矽、鎳及鎵 構成’且為n+型,即一 n+-GaNiSi薄膜。該歐姆接觸電極 64可由鈦·鋁合金構成。該基板33可為一石英姐幻基板 戈一氧化一銘(Al2〇3,Sapphire)基板。 本發明係採用高溫之常壓化學氣相沈積製程來製備該次 當量比氧化矽薄膜20,其化學反應式為:H: \ HU \ HYG \ Nuclear Energy Institute \ 92835 \ 92835.DOC -14-1233212 2 The wavelength is between _ 纟 85G nanometer and the peak wavelength is between 650 and 750 nanometers, which is the red light of visible light . FIG. 7 illustrates a light emitting diode 70 according to a second embodiment of the present invention. As shown in the figure, the light-emitting diode 70 includes a substrate 33, an alloy thin film 60 disposed on the substrate 33, and a second surface of the alloy thin film 60, a fossil evening film 26,- The transparent electrode X on the thin film 胄% is placed on the ohmic contact electrode 64 on the local surface of the alloy film 60. The silicon dioxide film 26 is prepared by the method described above, so it has silicon that can emit red light. Nano crystal 24. The alloy thin film 60 is composed of silicon, nickel, and gallium, and is an n + type, that is, an n + -GaNiSi thin film. The ohmic contact electrode 64 may be made of titanium and aluminum alloy. The substrate 33 may be a quartz The magic substrate is an Al2O3, Sapphire substrate. The present invention uses a high-temperature atmospheric pressure chemical vapor deposition process to prepare the sub-equivalent ratio silicon oxide film 20, and the chemical reaction formula is:
SiH2Cl2+ χΝ20-> SiOx+ xN2+ 2HC1 在沈積溫度(TD)介於700至11〇0。(:之高溫環境下,以氫 乳、氮氣或氬氣為運送氣體將預定摩爾數或體積比例之 SiH2Cl2與Νβ化合物均勻混合後送入高溫反應室之 中。在高溫反應室10之中,8汨2€:12與n2〇兩氣體將分別 被鬲溫解離成原子態後,再重組形成次當量比之氧化矽並 沈積於該基板22上。沈積於該基板22上之氧化矽包含過 剩石夕原子成份,而過剩矽原子成份之多募可利用非破壞檢 測方法測得其氧原子數與過剩矽原子數(〇/si)之相對比 例。例如,藉著量測其相對於標準二氧化矽(Si〇2)之光折射 能所 \92835\92835.DOC -15- 1233212 率大小即可推知氧原子數與過剩矽原子數(O/Si)之相對比 例0 矽之熔點(ΤΜ)約為143(TC,其結晶成核溫度(τΝ)約為〇 6 xT#858°C。該次當量比氧化矽薄膜2〇之沈積溫度(Td)係 介於700°C至1 i〇(rc,已明顯高於結晶成核溫度,因此在 "亥次當量比氧化矽薄膜20之沈積過程中,反應室1〇内之 高溫亦同時驅使該次當量比氧化矽薄膜20中之大部份過剩 夕原子形成矽奈米晶體核(Nucleus),且形成矽奈米晶體核與 母體(由二氧化矽構成)間之介面(Imerstate)結構。矽奈米晶體 與母體間之介面結構主要是由矽奈米晶體周邊之懸掛鍵 (<iangUngbonds)與氮·氧鍵所構成。例如,梦-氮鍵⑻氺 bonds)、妙-氧鍵(Si.〇 b〇nds)及石夕_氮氧鍵(si Nx 〇y)。該介面 結構是主要的螢光中心(luminescenee eenten〇。 之後,在含氧環境中進行石夕奈米晶體24之成長與熟化等 退火製程。該次當量比氧切薄膜2G之主要的結構組成包 含均質結構(Am〇1ph〇us)之氧化石夕與過剩石夕原子形成之尊聚 物(C1搶十其中過剩石夕原子羣聚物大部份已形成石夕奈米晶 體核。將該次當量比氧切薄膜2Q置於熱處理製程⑹之 咼溫環境中’並保持一段時間 T j tp以凡成所有矽奈米晶體24 之成長及介面結構之熟化,亦即 P將δ亥-人當置比氧化矽薄膜 20轉化成具有矽奈米晶體24 菔Μ之—氧化矽薄膜26。氧原子 可與矽原子有較強的鍵結槿, 埏…構介面結構矽_氮_氧鍵 (S卜Nx-Oy)是主要的螢光中 ^ 肩即鼠與氧原子的比例(x/y) 可獲得紅光螢光中心。較佳地, y不水晶體24之尺寸係控SiH2Cl2 + xN20- > SiOx + xN2 + 2HC1 has a deposition temperature (TD) between 700 and 1100. (: In a high temperature environment, using hydrogen milk, nitrogen or argon as the transport gas, uniformly mix a predetermined number of moles or volume ratio of SiH2Cl2 and Νβ compounds and send them into the high temperature reaction chamber. In the high temperature reaction chamber 10, 8汨 2 €: Two gases, 12 and n2O, will be dissociated into atomic state at high temperature, and then recombined to form silicon oxide of subequivalence ratio and deposited on the substrate 22. The silicon oxide deposited on the substrate 22 contains excess stone Even the atomic component and excess silicon atomic component can be measured by the non-destructive detection method to determine the relative ratio of the number of oxygen atoms to the number of excess silicon atoms (0 / si). For example, by measuring its relative to standard dioxide The refractive index of silicon (Si〇2) \ 92835 \ 92835.DOC -15-1233212 can be used to infer the relative ratio of the number of oxygen atoms to the number of excess silicon atoms (O / Si). 0 The melting point (TM) of silicon is about It is 143 (TC, and its crystallization nucleation temperature (τN) is about 0 6 xT # 858 ° C. The deposition temperature (Td) of this second equivalent to the silicon oxide film 20 is between 700 ° C and 1 i0 (rc Has been significantly higher than the crystallization and nucleation temperature, so the silicon dioxide film at 20 During the deposition process, the high temperature in the reaction chamber 10 also drove the excess equivalent atoms in the second equivalent silicon oxide film 20 to form silicon nanocrystalline nuclei, and formed the silicon nanocrystalline nuclei and the parent ( The structure of the interface between silicon dioxide and silicon. The interface structure between the silicon nanocrystal and the matrix is mainly composed of hang-down bonds (&n; iangUngbonds) and nitrogen-oxygen bonds around the silicon nanocrystal. For example, Dream-nitrogen bonds (bonds), myo-oxygen bonds (Si.〇b〇nds), and Shi Xi_nitrogen-oxygen bonds (si Nx 〇y). The interface structure is the main fluorescent center (luminescenee eenten). In an oxygen-containing environment, annealing processes such as the growth and maturation of Shixi nanocrystals 24 are performed. The main structural composition of the second equivalent oxygen cut film 2G includes a homogeneous structure (Am〇1ph〇us) of oxidized stone and excess Polymers formed by Shixi Atoms (C1 steals most of the excess Shixi Atomic Groups, and most of the Shixi Nanocrystalline nuclei have been formed. This sub-equivalent ratio oxygen cut film 2Q is placed in the high temperature environment of heat treatment 'And hold for a period of time T j tp The growth of silicon nanocrystals 24 and the maturation of the interface structure, that is, P converts the δH-human-ratio silicon oxide film 20 into silicon oxide films 26 with silicon nanocrystals 24 μM. Oxygen atoms can interact with silicon Atoms have strong bonds, 埏 ... the interface structure of silicon-nitrogen-oxygen bonds (SbNx-Oy) is the main fluorescent light ^ shoulder is the ratio of rat to oxygen atoms (x / y) can get red Photofluorescence center. Preferably, the size of the y-free crystal 24 is controlled
H:\HU\HYG\ 核能所 \92835\92835.DOC -16- 1233212 制於3至8奈米之間。 此外,若該次當量比氧化矽薄膜2〇内之過剩矽原子未在 該沈積製程中形成矽晶體核,該熱處理程序之高溫則進一 步地驅使該次當量比氧化矽薄膜2〇内之過剩矽原子成核。 然後’將具有矽奈米晶體24之二氧化矽薄膜26置於氫氣 環境中’並維持在一預定溫度TpH與時間tPH以進行該矽奈 米晶體24之表面氫鈍化處理(Hy(jr〇gen passivati〇n)。完成該表 面純化處理後,具有矽奈米晶體24之二氧化矽薄膜26即 形成穩定的紅光發光薄膜。 相較於習知之技藝,本發明係利用高溫之常壓化學氣相 沈積技術以及熱處理技術製備具有含矽發光薄膜(即具有 石夕奈米晶體24之二氧化矽薄膜26)之紅光發光二極體50, 具有下列之優點: 1 ·本發明不需使用繁複的磊晶製程與昂貴的製程設備,僅 需沈積一層次當量比氧化矽薄膜26與熱處理製程,具 有製程簡單與快速之優點。 2·本發明係利用常壓化學氣相沈積製程製備該次當量比 氧化矽薄膜20,而常壓化學氣相製程可整合於標準化 的半導體製程之中,因而本發明具有大量生產發光二極 體之優點。 3·習知技藝利用III-V族化合物製備發光元件之發光薄膜 因而製造成本昂貴,本發明係使用氧化矽來製備發光二 極體50之含矽發光薄膜,因而材料與製作成本均相對 地較低廉。 HAHlAHYGVfli 能所 W2835\92835.DOC -17- 1233212 4.習知技術使用之III-V族化合物會產生有毒化學物質, 本發明係使用氧化矽製備發光元件之含矽發光薄膜,並 無化學與有毒重金屬之使用與排放問題,為綠色環保製 程。 5·本發明選擇高溫條件形成含有過剩矽原子之次當量 比氧化矽薄膜20,再經熱處理而轉化成具有矽奈米晶 體24之二氧化石夕薄膜26,其具有較高的溫度穩定性, 且具有窄寬幅的紅光光譜分佈。 6·高溫TP熱處理後之當量比二氧化矽薄膜26具有較高緻 密性、較高密度分佈之矽奈米晶體24以及較低的雜 質’因而石夕奈米晶體24與其介面結構經激發可產生較 清晰與高亮度之光譜。 本發明之技術内容及技術特點已揭示如上,然而熟悉本 項技術之人士仍可能基於本發明之教示及揭示而作種種不 背離本發明精神之替換及修飾。因此,本發明之保護範圍 應不限於實施例所揭示者,而應包括各種不背離本發明之 替換及修飾,並為以下之申請專利範圍所涵蓋。 【圖式簡要說明】 圖1係一常壓化學氣相沈積裝置之示意圖; 圖2至圖4例示本發明發光二極體之製備方法; 圖5例示本發明之沈積程序、熱處理程序及表面鈍化程 序之操作溫度及時間; 圖6係本發明之二氧化矽薄膜之矽奈米晶體的光激螢光 光谱圖;以及H: \ HU \ HYG \ Nuclear Energy Institute \ 92835 \ 92835.DOC -16-1233212 is between 3 and 8 nanometers. In addition, if the excess silicon atoms in the second equivalent silicon oxide film do not form a silicon crystal core in the deposition process, the high temperature of the heat treatment process will further drive the excess equivalent silicon in the second silicon oxide film within 20 Atom nucleation. Then, 'the silicon dioxide film 26 having the silicon nanocrystal 24 is placed in a hydrogen environment' and maintained at a predetermined temperature TpH and time tPH to perform a hydrogen passivation treatment on the surface of the silicon nanocrystal 24 (Hy (jr〇gen passivati). After the surface purification treatment is completed, the silicon dioxide film 26 having silicon nanocrystals 24 forms a stable red light-emitting film. Compared with the conventional technology, the present invention uses a high-temperature atmospheric pressure chemical gas. Phase deposition technology and heat treatment technology to prepare a red light-emitting diode 50 with a silicon-containing light-emitting film (that is, a silicon dioxide film 26 with shixi nanocrystals 24) have the following advantages: 1 The invention does not require the use of complicated The epitaxial process and expensive process equipment only need to deposit a layer of equivalent ratio of silicon oxide film 26 and heat treatment process, which has the advantages of simple and fast process. 2. The present invention uses atmospheric pressure chemical vapor deposition process to prepare the equivalent Compared with the silicon oxide film 20, the atmospheric pressure chemical vapor phase process can be integrated into the standardized semiconductor process, so the present invention has the advantage of mass production of light emitting diodes. The know-how uses III-V compounds to prepare light-emitting films of light-emitting elements and thus is expensive to manufacture. The present invention uses silicon oxide to prepare silicon-containing light-emitting films of light-emitting diodes 50, so the materials and manufacturing costs are relatively low. HAHlAHYGVfli Energy Institute W2835 \ 92835.DOC -17-1233212 4. Group III-V compounds used in conventional technology can produce toxic chemicals. The present invention uses silicon oxide to prepare silicon-containing light-emitting films of light-emitting elements, and is free of chemical and toxic heavy metals. The problem of use and emission is a green process. 5. The present invention selects high temperature conditions to form a silicon oxide film 20 with a second equivalent ratio of excess silicon atoms, and then heat-treated to convert it into a silicon dioxide film with a silicon nanocrystal 24. 26, which has high temperature stability, and has a narrow and wide red light spectrum distribution. 6 · Since high temperature TP heat treatment, the equivalent of silicon dioxide film with higher density and higher density distribution than silicon dioxide film 26 The crystal 24 and the lower impurities', therefore, the Shixinan crystal 24 and its interface structure can be excited to produce a clearer and higher brightness spectrum. The technical content and technical features have been disclosed as above, but those familiar with the technology may still make various substitutions and modifications without departing from the spirit of the invention based on the teaching and disclosure of the invention. Therefore, the scope of protection of the invention should not be limited to the embodiments The disclosed should include various substitutions and modifications that do not depart from the present invention, and are covered by the following patent applications. [Brief Description of the Drawings] Figure 1 is a schematic diagram of an atmospheric chemical vapor deposition device; Figures 2 to Figure 4 illustrates the method for preparing the light-emitting diode of the present invention; Figure 5 illustrates the operating temperature and time of the deposition process, heat treatment process, and surface passivation process of the present invention; Figure 6 shows the silicon nanocrystals of the silicon dioxide film of the present invention. Photo-induced fluorescence spectrum; and
HAHU\HYG\ 核能所\92835\92835.DOC -18 - 1233212 圖7例示本發明第二實施例之發光二極體。 【元件符號說明】 10 反應室 11 運送氣體 12 局頻振盈電源 14 石墨塊 15 薄膜 16 進氣岐管 17 反應氣體 18 出氣岐管 19 反應副產物 20 次當量比氧化石夕薄膜 22 基板 23A上表面 23B 下表面 24 矽奈米晶體 26 二氧化碎薄膜 28 透明電極 30 歐姆接觸電極 40 紅光 33 基板 50 發光二極體 60 合金薄膜 64 歐姆接觸電極 70 發光二極體 100 化學氣相沈積裝置 H:\HU\HYG\ 核能所\92835\92835.DOC -19-HAHU \ HYG \ Nuclear Energy Institute \ 92835 \ 92835.DOC -18-1233212 Fig. 7 illustrates a light emitting diode according to a second embodiment of the present invention. [Description of component symbols] 10 Reaction chamber 11 Gas transport 12 Local frequency vibration power supply 14 Graphite block 15 Thin film 16 Intake manifold 17 Reactive gas 18 Outlet manifold 19 Reaction byproducts 20 times equivalent ratio Oxide film 22 Substrate 23A Surface 23B Lower surface 24 Silicon nanocrystals 26 Dioxide shattered film 28 Transparent electrode 30 Ohm contact electrode 40 Red light 33 Substrate 50 Light emitting diode 60 Alloy film 64 Ohm contact electrode 70 Light emitting diode 100 Chemical vapor deposition device H : \ HU \ HYG \ Nuclear Energy Institute \ 92835 \ 92835.DOC -19-
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