基于Ⅲ-Ⅴ族氮化物尤其是AlGaN三元化合物的紫外發(fā)光二極管（UV-LED）與傳統(tǒng)紫外光源相比具有體積小、可靠性高、低成本和低能耗的優(yōu)勢,并且發(fā)光波長可在200-365 nm之間任意調(diào)節(jié)。然而UV-LED的外量子效率依然處于較低的水平,這主要的原因在于金屬與AlGaN之間歐姆接觸較差,以及光子提取效率較低。因為歐姆接觸為載流子提供了單向的流通通道,因此對于LED來說,好的歐姆接觸十分重要。為了解決這些問題,有必要設計并制備新的LED結構。研究中發(fā)現(xiàn),橫向極性結構（LPS）可以實現(xiàn)較好的歐姆接觸。此外,通過合適的極性調(diào)控手段,我制備了無等離子體損傷的納米柱結構,從而提升了 LED的光子提取效率。此論文主要分為四個部分。第一章主要講述氮化物極性調(diào)控的研究背景。第二章主要講述橫向極性結構對于器件歐姆接觸性能的影響。首先,通過在一個襯底上同時生長金屬極性和氮極性材料,我制備了橫向極性結構GaN和AlGaN。在此基礎上,利用氮極性載流子濃度高,而金屬極性電阻率高的特點,我制備了肖特基二極管（SBD）橫向極性結構器件。通過在器件表面進行鈍化處理,器件的反向漏電流減小了2個數(shù)量級,證明了鈍化處理對于... 

【文章來源】：中國科學院大學(中國科學院寧波材料技術與工程研究所)浙江省

【文章頁數(shù)】：73 頁

【學位級別】：碩士

【文章目錄】：
摘要
Abstract
1. Introduction
    1.1. Background and significance of the topic
    1.2. Metalorganic Chemical Vapor Deposition(MOCVD)
    1.3. Latest development and trends in optoelectronic and electronic device
        1.3.1. General review of optoelectronic and power electronics
            1.3.1.1. UV-A(340-400 nm)LEDs
            1.3.1.2. UV-B(290-340 nm)LEDs and UV-C(100-290 nm)LEDs
            1.3.1.3. Current Progress and limitations of Schottky barrier diodes
        1.3.2. Ohmic contact in electronic devices and optoelectronic devices
        1.3.3. Improvement of light extraction in LED devices
    1.4. Polarity control in Ⅲ-nitride and its applications
2. Polarity Control of GaN and Realization of GaN Schottky Barrier Diode Basedon Lateral-Polarity-Structure
    2.1. Overview
    2.2. Experiments and methods
    2.3. Results and discussions
        2.3.1. AFM and SEM of N-polar and Ga-polar surface
        2.3.2. Strain condition (Raman spectroscopy)
        2.3.3. Current-Voltage characteristic
    2.4. Summary
3. Design and fabrication of nanoscale LPS in light emission control of LEDdevices
    3.1. Overview
    3.2. Experiments and methods
        3.2.1. Design and fabrication of LPS
            3.2.1.1. Low temperature AIN buffer patterning using RIE etching
            3.2.1.2. Low temperature AIN buffer patterning by wet chemical etching
    3.3. Results and discussions
        3.3.1. SEM on surface morphology
        3.3.2. PL measurement 3373.4. Summary
    3.4. Summary
4. Metals network contact on p-GaN for LED light extraction
    4.1. Overview
    4.2. Experiments and methods
        4.2.1. Planer sample
    4.3. Results and discussions
        4.3.1. SEM on surface morphology
        4.3.2. I-V characteristic
    4.4. Summary
5. Concusion and possible future work
References
Acknowledgement
Author's resume and academic papers and research results published during the degree stud



本文編號：3451341