DC 欄位 |
值 |
語言 |
DC.contributor | 光電科學與工程學系 | zh_TW |
DC.creator | 李孟泓 | zh_TW |
DC.creator | Li-Meng Hong | en_US |
dc.date.accessioned | 2023-7-18T07:39:07Z | |
dc.date.available | 2023-7-18T07:39:07Z | |
dc.date.issued | 2023 | |
dc.identifier.uri | http://ir.lib.ncu.edu.tw:88/thesis/view_etd.asp?URN=110226064 | |
dc.contributor.department | 光電科學與工程學系 | zh_TW |
DC.description | 國立中央大學 | zh_TW |
DC.description | National Central University | en_US |
dc.description.abstract | 深紫外發光二極體(波長≤290 nm)在目前的設計中通常選用P型結構來提高導電性。然而,P型結構中鎂離子的摻雜會形成中間能階(位於價電帶邊界上方約 150~220 meV ),此能階會吸收量子井中載子複合後所產生的紫外光,降低元件的發光效率。因此,我們致力於開發一種以未摻雜的GaN和高品質的AlN結構形成的二維電洞氣(2-dimensional hole gas, 2DHG)來實現高導電、高穿透的性能。利用二維電洞氣,我們能解決使用P型結構中摻雜鎂離子所引起的吸光問題。同時,由於二維電洞氣之磊晶層的厚度相對傳統P型結構更薄,更能減緩P型磊晶層的吸光問題,達成高紫外光穿透的目標。
在本研究中,我們利用一維 drift-diffusion charge control solver (1D DDCC) 軟體進行能帶模擬。從模擬結果中觀察到,在15 nm的GaN磊晶覆蓋層厚度下,AlGaN量子井表面的電洞濃度可達最大值9.7×1020 cm-3。本研究使用有機金屬化學氣相沉積法成長GaN/AlN磊晶層,希望得到高品質的二維電洞氣。我們以兩吋c-plane藍寶石為基板,先成長一層AlN,再成長GaN。透過磊晶時間來調整GaN磊晶層的厚度,並分析不同厚度的GaN對於磊晶品質和元件電性的影響。未來,我們將持續優化二維電洞氣的磊晶條件,以提高磊晶品質,並將其應用於DUV LED結構,以提升發光效率。 | zh_TW |
dc.description.abstract | Deep ultraviolet light-emitting diodes (DUV LEDs, wavelength ≤ 290 nm) typically utilize a p-type contact layer to control the current spreading and light extraction efficiency. However, doping with magnesium acceptors in the p-type layer creates impurity levels (150~220 meV above the valence band), which absorb the ultraviolet light generated by carrier recombination in the quantum well. Therefore, we are devoted to developing a two-dimensional hole gas (2DHG) formed by undoped GaN and high-quality AlN structures to achieve high conductivity and high transparency. Using the 2DHG, we can overcome the light absorption issues caused by impurity levels. Additionally, the thin (< 30 nm) epitaxial layer of 2DHG can minimize the UV absorption.
In this study, we conducted simulations using a one-dimensional drift-diffusion charge control (DDCC) solver. From the simulation results, it was observed that the hole concentration reached a maximum value of 9.7×1020 cm-3 at the GaN capping layer thickness of 15 nm on the AlGaN quantum wells. To grow high-quality 2DHG, we employed metal-organic chemical vapor deposition (MOCVD) and 2-inch c-plane sapphire substrates. We aim to form the 2DHG by the interface of GaN/AlN. The epitaxial thickness of GaN was controlled by adjusting the growth time, and the effect of GaN layer thicknesses on epitaxial quality and device electrical properties was investigated. | en_US |
DC.subject | 二維電洞氣 | zh_TW |
DC.title | 應用於紫外光二極體的氮化物二維電洞氣 | zh_TW |
dc.language.iso | zh-TW | zh-TW |
DC.title | Nitride-based two dimensional hole gas for UV LED applications | en_US |
DC.type | 博碩士論文 | zh_TW |
DC.type | thesis | en_US |
DC.publisher | National Central University | en_US |