本論文主要設計1920x1080 氮化鎵微型發光二極體陣列，利用自動對準的技術縮小像素間距使其小於10微米，並且利用銦錫氧化物(ITO)來改善微型發光二極體陣列的特性，主要研製的波段是綠光525奈米，藍光450奈米，以及紫光400奈米。在圖形化的藍寶石基板(PSS)上，用有機金屬化學氣相沉積系統(MOCVD)製作出氮化鎵磊晶層，再利用感應偶合電漿離子蝕刻系統(ICP-RIE)蝕刻出磊晶層的高原(MESA)，最後鍍上n與p電極。
日常生活中，發光二極體主要應用照明或是標誌為主，但我們希望將發光二極體提升至更進一步的應用，像是投影機或是顯示器，因此需要將發光二極體做成陣列，下一帶的顯示器可能會以微型發光二極體陣列為目標，像是頭戴式顯示器虛擬實境，亦或是手機，這類的現在解析度都要求越來越高，因此我們如何能製作一個微小的發光二極體並且是高解析度的陣列，以及均勻發光，這些都是相當重要的。首先，磊晶片包含十層量子井，其能夠盡可能增加電子電洞復合並轉換成光子，提高發光效率；在磊晶片上，我們使用兩種製成，其一是利用鎳作為p+型氮化鎵形成歐姆接觸，並且設計網格狀的n型電極，使電流至每個像素的路徑一致，達到高均勻亮度。另一種則是利用銦錫氧化物(ITO)的透明導電膜層作為p+型氮化鎵形成歐姆接觸，目的是減少接觸電阻達到更好的歐姆接觸，達到特性優化的效果。
在本論文中1920x1080微型發光二極體陣列，像素為5微米，各個像素距離為8微米。而我們的微型發光二極體陣列皆使用投影機與螢幕的常見比例16:9作為設計，尺寸是在0.69吋，像素密度是3178.8。自動對準技術的關鍵在於ICP蝕刻，而達到高原呈現啞鈴型，進而製作出1920×1080微型發光二極體陣列，而各種波段的特性如下：在10伏特的逆偏壓下綠光波段的漏電流為0.094 pA，藍光波段的漏電流為1.2 pA，紫光波段的漏電流為2.2 pA。在正偏壓下，綠光波段的導通電壓為2.59伏特，藍光波段的導通電壓為2.83伏特，紫光波段的導通電壓為3.0伏特。在注入1 mA電流下，綠光波段的光輸出功率為25.3 μW，藍光波段的光輸出功率為33.0 μW，紫光波段的光輸出功率為99.5 μW。綠光波段最好的外部量子效率是2.65 %，藍光波段最好的外部量子效率是3.47 %，紫光波段最好的外部量子效率是5.15 %。綠光波段最好的電光轉化效率是1.89%，藍光波段最好的電光轉化效率是2.80%，紫光波段最好的電光轉化效率是5.09%。

In this thesis, the major design 1920x1080 Gallium Nitride (GaN) based micro light emitting diode array which pixel pitch is less than 10μm by self-aligned technology, and uses indium tin oxide (ITO) to improve the characteristics of the micro-light-emitting diode array. The main development bands are green light 525 nm, blue light 450 nm, and purple light 400 nm. On the patterned sapphire substrate (PSS), a Gallium Nitride epitaxial layer was formed by a metalorganic chemical vapor deposition system (MOCVD), and an epitaxial layer was etched by an inductively coupled plasma ion etching (ICP-RIE) system. a MESA of epitaxial layer is then formed, after n-metal and p-metal is deposited.
In daily life, the LEDs are mainly used for lighting or signage, but we hope to make good use of LED’s tremendous advantages, such as projectors or displays, so we need to make the LEDs into an array. In the future, the next display may target a miniature LED array, such as a virtual reality headset or a mobile phone. This type of resolution is now getting higher and higher, so how can we make it? A micro light-emitting diode and a high-resolution micro-LED array, as well as uniform illumination, are all very important. First, the epitaxial wafer contains ten layers of quantum wells, which can increase the electron hole recombination and convert it into photons as much as possible, and improve the luminous efficiency. On the epitaxial wafer, we use two kinds, one of which is to use Nickel as p+ type GaN forms an ohmic contact and a grid-shaped n-type electrode is designed to align the current to each pixel to achieve a high uniform brightness. The other is to use an indium tin oxide (ITO) transparent conductive film layer as p+ type GaN to form an ohmic contact, in order to reduce the contact resistance to achieve a better ohmic contact, to achieve the characteristics of the optimization effect.
In this thesis, the 1920x1080 miniature light-emitting diode array has a pixel of 5 microns and a distance of 8 microns for each pixel. And our miniature LED arrays which the size is 0.69 inch use a 16:9 ratio of the projector or the screen and pixel per inch is 3178.8. The key to the self-aligned technology is ICP etching and the MESA is dumbbell-shaped, and a 1920×1080 micro-LED array is fabricated. For a single pixel characteristic of 1920×1080 micro-LEDs array are as follows: the leakage of the green light band under the reverse bias of 10 volts The current is 0.094 pA, the leakage current in the blue band is 1.2 pA, and the leakage current in the violet band is 2.2 pA. Under positive bias, the on-voltage of the green band is 2.59 volts, the on-voltage of the blue band is 2.83 volts, and the on-voltage of the violet band is 3.0 volts. At a current of 1 mA, the optical output power of the green band is 25.3 μW, the optical output power of the blue band is 33.0 μW, and the optical output power of the violet band is 99.5 μW. The best external quantum efficiency in the green band is 2.65%, the best external quantum efficiency in the blue band is 3.47%, and the best external quantum efficiency in the violet band is 5.15%. The best electro-optical conversion efficiency in the green band is 1.89%, the best electro-optical conversion efficiency in the blue band is 2.80%, and the best electro-optical conversion efficiency in the violet band is 5.09%.

摘要 I
ABSTRACT III
致謝 VI
TABLE OF CONTENTS VIII
LIST OF FIGURE XI
LIST OF TABLE XV
CHAPTER 1 INTRODUCTION 1
1-1 Introduction to Light Emitting Diodes 1
1-2 Application of Light Emitting Diodes 2
1-3 Research Motivation 3
CHAPTER 2 THE BASIC THEORY 8
2-1 The basic theory of Light Emitting Diodes 8
2-2 LED I-V Curve Characteristic 9
2-3 LED L-I Curve Characteristic 16
2-4 LED E-L Curve Characteristic 20
CHAPTER 3 EXPERIMENTAL PROCEDURE 23
3-1 Device Structure and Mask Design Concept 23
3-2 Process Steps and Experimental Details 27
3-2-1 Process steps for 1920×1080 micro-LED array without ITO 27
3-2-2 Process steps for 1920×1080 micro-LED array with ITO 30
3-3 Measurement Means and Characterization Instruments 34
3-3-1 Transmission line measurement 34
3-3-2 I-V measurement system 36
3-3-3 L-I and E-L measurement system 37
CHAPTER 4 MEASUREMENT RESULTS AND DISCUSSION 39
4-1 The 1920 × 1080 micro-LED Array Without ITO 39
4-1-1 Ni current spreading and p-metal contact resistance 39
4-1-2 I-V characteristic and analysis 42
4-1-3 L-I characteristic and analysis 46
4-2 The 1920 × 1080 Micro-LED Array Without ITO 50
4-2-1 ITO current spreading and p-metal contact resistance 50
4-2-2 I-V characteristic and analysis 52
4-2-3 L-I characteristic and analysis 56
4-2-4 E-L characteristic and analysis 60
4-3 Comparison and Results 62
4-3-1 Compare the I-V characteristics 62
4-3-2 Compare the L-I characteristics 64
CHAPTER 5 CONCLUSION AND FUTURE WORK 67
5-1 Conclusion 67
REFERENCE 68

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