請用此 Handle URI 來引用此文件: http://hdl.handle.net/11455/47584
標題: Epitaxial Growth of ZnO-Based Compound Semiconductors Using MOCVD
氧化鋅系列磊晶材料及光電元件之整合研究-子計畫一:以MOCVD進行氧化鋅系列材料磊晶成長之研究
作者: 武東星
關鍵字: 基礎研究
ZnO
光電工程
氧化鋅
P 型穩定化
有機金屬化學氣相磊晶
異質結構
發光二極體
UV 檢光器
固態照明
P-type Stability
MOCVD
Heterostructure
LED
UV Detector
Solid-StateLighting
摘要: Semiconductor light source is world-widely recognized as a new generation of lightingproducts with the advantages of power saving, safety, environment friendliness, long service life,colorfulness and miniaturization. It will be another symbolic leap after incandescent and fluorescentlamp in lighting history. The potential high efficiency of white light LEDs offers the promise ofsignificantly reducing this energy usage, but first, higher efficiency and lower costs will be required.The inherent, high luminous efficiency of ZnO will result in increased efficiency and lower costthan current technology. Therefore, the ZnO constitutes an ideal material for this issue, mainlybecause excess electrons and holes form tightly-bound excitons, which lead to very efficientnear-band-gap recombination at room temperature and even higher. Other advantages of ZnO as anemitter, especially with respect to its chief rival, GaN, are the availability of large-area ZnOsubstrates, the possibility of low-temperature epitaxial growth, and excellent radiation hardness.Accordingly, we have organized a research team in which four professors who majors in materialgrowth, optical measurement and simulation, semiconductor process and optical device processrespectively will devote them in studying the key technology of ZnO-based optical devices. Thepurpose of this project is to study of the ZnO film grown by metalorganic chemical vapordeposition (MOCVD). MOCVD method is very suitable for various semiconductor growths andwith the high speed degree grows up the good ZnO thin film. Moreover, MOCVD can growmultiple-layer structure easily. Particularly, under the low pressure operation, the MOCVD methodcan increase the gas velocity meanwhile, avoiding the per-reaction between the group II and IV tofurther enhancement the doping efficiency.In the 1st year, we will modify the Veeco D180 system and study the n-type ZnO epitaxialgrowth on various substrate materials (such as conductive ZnO, sapphire and SiC). The effect ofdislocation density on the ZnO quality will be investigated. The resistivity, carrier concentration,and mobility for n-type ZnO are expected to be 1018 cm-3, and >100 cm2/V-s,respectively. The optical and electrical characteristics of the n-type ZnO film will be studied withthe collaboration of sub-project 2. The doping behavior and mechanism of ZnO will be emphasized.Accordingly, in the 2nd year, we will develop high-quality p-type ZnO epilayer and p-njunction structure using different doping and stabilizing processes. The resistivity, carrierconcentration, and mobility for p-type ZnO are expected to be 1017 cm-3, and >20cm2/V-s, respectively. The collaboration of sub-project 2, 3 & 4 will share the experiences in order to realize more rigid results. Finally, based up on the 2nd year ZnO p-n junction structure developedby this program and the device simulation results in the sub-project 2, the ZnO-based LEDs will beverified in the 3rd year. In order to improve the luminescence efficiency at ZnO-based light emitting,the structure design of multiple-quantum-well (MQW) and the carrier conferment in MQW are thekey points. Different MQW structure, including different well (CdZnO alloy) and barrier (MgZnO)materials compositions, well width and doping conditions, will be investigated in this stage. Thetarget of this three-year project is to develop a optimum UV-A (320-400 nm) white LED achievingluminescence efficiency greater than 100 lm/W. The improvements in the optical and electricalproperties are expected to enhance the long-term reliability of the ZnO-based LED devices forfuture advanced solid-state-lighting industry.
近年來發光二極體逐漸被應用於固態照明領域,而高發光效率和低製造成本則是未來能否實現全固態照明的兩個關鍵挑戰。氧化鋅(ZnO)是非常符合上述條件的一種光電半導體材料,它具有載子束?能高、材料取得容易、生長溫度低、發光效率高、容易加工製成元件等優點,有鑑於此,我們整合包含磊晶材料成長、光電元件製程、元件設計與光電量測等不同領域的四位教授來研發高效率氧化鋅二極體的關鍵技術。本計畫將採用「有機金屬化學氣相磊晶法(MOCVD)」來成長ZnO系列材料,MOCVD十分適合各種化合物半導體異質結構的成長,可以高速度成長出均勻性佳的ZnO磊晶膜,主持人亦親赴國外多次實地進行系統設計與改裝驗證,已能掌握ZnO磊晶成長系統之基本關鍵。本計畫第一年將以本研究群已具經驗之Veeco D180系統在不同基板(sapphire、ZnO、SiC等)上進行ZnO之同(異)質磊晶成長,探討N型ZnO之光電特性,我們目標是希望達到電阻率小於 10-2 Ω cm,載子濃度大於1018 cm-3,載子遷移率大於100 cm2/V-s,同時並研究其磊晶成長之缺陷效應,我們也將進一步分析不同成長參數對磊晶膜特性的影響。本計畫第二年將開發製備P型ZnO磊晶膜,其中P型ZnO之穩定化機制也是急待突破之瓶頸,我們目標是希望達到電阻率小於 10-1 Ω cm,載子濃度大於1017 cm-3,載子遷移率大於20cm2/V-s,結合「子計畫二」之元件結構設計與模擬,協同「子計畫三」完成氧化鋅p-n異質接面發光二極體製作。計畫第三年,依據p-n異質接面發光二極體開發經驗,研製提高亮度之雙異質與多重量子井結構之氧化鋅發光二極體,我們也將進一步分析不同多重量子井結構,包含不同位能井(CdZnO alloy)與位障層(MgZnO)材料、寬度、?雜方式,對發光特性的影響,我們的目標是希望達到在UV-A (320-400 nm)波段之白光二極體效率大於100 lm/W,光偵檢器的暗電流(在5伏特下驅動)小於1 nA,光響應值大於0.5 A/W,並開發UV B (280-320 nm)波段的發光二極體,光偵檢器的暗電流(在5伏特下驅動)小於1 nA,光響應值大於0.3 A/W,並與其他子計畫之製程分析做應用整合,改善ZnO磊晶膜之光電特性,期望能提高ZnO發光二極體元件可靠度,期望能為我國固態照明產業開闢新猷。
URI: http://hdl.handle.net/11455/47584
其他識別: NSC95-2221-E005-131-MY3
顯示於類別:材料科學與工程學系

文件中的檔案:
沒有與此文件相關的檔案。


在 DSpace 系統中的文件,除了特別指名其著作權條款之外,均受到著作權保護,並且保留所有的權利。