氧化鋅/氮化鎵雙異質接面發光二極體之製作與研究

Investigation and Fabrication on The ZnO/GaN Double-Heterojunction Light-Emitting Diode

楊凱兆(Kai-Chao Yang)

指導教授 ： 劉代山

國立虎尾科技大學/電機資訊學院/光電與材料科技研究所/碩士(2014年)

摘要

本研究利用射頻磁控共濺鍍系統，分別使用氮化鋁-氧化鋅、氧化鎂-氧化鋅靶材製作出未摻雜氧化鋅薄膜與氮化鋁-氧化鋅與氧化鎂-氧化鋅共濺鍍薄膜，並製作出氮化鋁-氧化鋅及氧化鎂-氧化鋅雙異質結構，針對不同主動層厚度之雙異質結構，利用光激發螢光量測與霍爾量測探討其兩種結構之氧化鋅NBE強度與薄膜元件電特性，在氮化鋁-氧化鋅雙異質結構方面，發現其短波長的NBE放射強度值隨主動區厚度的減少而減弱且其半高寬有變寬的現象，霍爾電特性量測薄膜載子濃度則是有逐漸下降的情況，從I-V曲線量測發現降低主動層厚度可以降低串聯電阻及啟動電壓，在電激發螢光量測中觀察到主動層100nm結構下為420 nm與550 nm的發光波段，CIE色座標為白光(CIE 1931 x=0.351, y=0.340)，當主動層厚度下降時，會造成長波段的相對強度逐漸下降，短波長的發光峰值半高寬有減少的現象，而當主動層降低至10nm時，由於主動層受鋁原子擴散影響，可以有效抑制長波段的缺陷，使元件之發光機制係屬能帶與能帶之間傳輸的機制，在電激發光螢光量測中所測量得403 nm波段為一藍紫光，說明主動層的下降，可以有效增強其短波長的發光強度。而氧化鎂-氧化鋅方面，從光激發螢光量測中發現，為兩個主要缺陷峰值分別位於480 nm的鋅空缺、550 nm的氧空缺位置，經由線性擬合結果發現，有抑制氧空缺趨勢，量測其薄膜載子濃度也有下降的現象，而元件的電流-電壓曲線可以發現，隨著主動層的下降，串聯電阻與啟動電壓分別隨之下降，在電激發螢光量測中發現，主動層100 nm結構下有480 nm與550 nm的發光波段，CIE色座標圖為暖白光( CIE1931 x=0.346, y=0.367)，而當主動層下降至10 nm時，其CIE色座標圖為橘黃光( CIE1931 x=0.416, y=0.402)，因鎂原子的擴散更為明顯，使得元件經真空熱處理後的發光峰值以Ga-O鍵結為主要的缺陷發光峰值。

關鍵字

射頻磁控共濺鍍 ； 氮化鋁 ； 氧化鎂 ； 氧化鋅 ； 雙異質結構 ； 發光二極體

並列摘要

In this thesis, we use of RF magnetron co-sputtering system to deposite aluminum nitride - zinc oxide, magnesium oxide - zinc oxide target respectively that to produce a non-doped ZnO films and aluminum nitride - zinc oxide and magnesium oxide - zinc oxide were splashing plating film, and produce aluminum nitride - zinc oxide and magnesium oxide - zinc oxide double heterostructure for double hetero-junction(DH) structure with different active layer of thickness , the use of photoluminescence(PL) measurements and Hall measurements investigate the oxidation of its two structures NBE zinc film strength and electrical properties of elements in the aluminum nitride - zinc oxide aspect double hetero structure, the intensity values found NBE radiation with a short wavelength while reducing the thickness of the active layer area and having a Full Width half-maxmaiun decreased with wider phenomenon Hall Seoul measuring the electrical characteristics of the film carrier concentration is a gradual decline, reducing the thickness of the active layer from the current-Voltage curve measurements found to reduce the series resistance and the starting Voltage electrical excitation in fluorescence measurements observed in the active layer structure under 100nm a light emitting wavelength of 420 nm and 550 nm, CIE color coordinates of white light (CIE 1931 x = 0.351, y = 0.340), when the thickness of the active layer decreased, the relative intensity will cause a gradual decrease in the long wavelength region, a short wavelength light emission peak half a decrease in the aspect of the phenomenon, and when the active layer is reduced to 10nm, due to the impact of the active layer by diffusion of aluminum atoms, can effectively suppress long wavelength defects, making mechanism based light-emitting element band mechanism and energy transfer between the metal band in electrical excitation 403 nm wavelength light in the measured fluorescence was measured as a blue-violet light, indicating that the decline in the active layer can effectively enhance its short wavelength emission intensity. The magnesium oxide - zinc oxide, the photoluminescence measurements from found two major flaws peaking at 480 nm of zinc vacancies, oxygen vacancies position 550 nm, the linear fit through the results found that inhibition of oxygen vacancies trends, measure its film carrier concentration also declined phenomenon, and current components - Voltage curve can be found, with the decline in the active layer, followed by the series resistance and the starting Voltage drop, respectively, in the electrical excitation fluorescence measurements found , the structure of the active layer 100 nm 480 nm 550 nm and the light emission wavelength, CIE color coordinates Pictured warm white (CIE1931 x = 0.346, y = 0.367), and when the active layer is decreased to 10 nm, the CIE color coordinates of FIG. for the orange light (CIE1931 x = 0.416, y = 0.402), due to the proliferation of magnesium atoms is more obvious, making the light-emitting element by vacuum heat treatment after the peak in Ga-O bond became a major defect emission peak.

並列關鍵字

RF magnetron sputtering ； AlN ； MgO ； ZnO ； double-heterojunction ； Light-emitting diode

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