電漿原子層沉積之氮氧銦鎵薄膜與發光二極體特性研究

Abstract

本研究主要探討了以氧氮化鎵(GaON)與氧化銦(In2O3)色心發光元件所製的色心自發光白光二極體。先採用 250 °C的電漿輔助原子層沉積系統(PE-ALD)調整 O₂/NH₃ 流量控制缺陷組態，並以 XPS、PL解析整體的發光效果。結果顯示，多氧空缺可形成覆蓋 400~800 nm 的連續能階，配合氧化銦錫(ITO:Indium tin oxide) 與氧化鎵摻雜鋅(GZO:Ga-doped ZnO)透明導電層及 Fabry-Perot 共振腔設計，可以大幅度改變整體的發光光譜，同時於在厚度約10nm下的 GaON 薄膜觀測到了大量的負微分電阻情形，此類情形可以使用穿隧效應來解釋，並且使用不同的基板結構配合AFM進行量測驗證。及在較高厚度下的單一負微分電阻，證實缺陷捕獲釋放載子所誘發的發光行為。綜合以上，本研究說明 GaON、In2O3寬能隙半導體色心白光發光機制與缺陷光譜，提供了更多種類型的全彩光譜選擇。 本文主要分為五個章節，第一章講述了LED簡介及研究動機，最後提到了整體論文的大綱。第二章講述了LED的發光原理及本次研究的色心發光原理、共振腔模型。第三章介紹了本次實驗使用的機台，包含了濺鍍機，電漿輔助原子層沉積系統。第四章節說明了本次元件的製作方法及透明導電薄膜的量測，最後第五章說明了整體的量測系統，搭配了量測數據進而驗證整體內容的正確性。最後一章為結論與未來展望，希望以此結構讓白光LED能有更進一步的發展。

This study investigates color-center light-emitting diodes fabricated from gallium oxynitride (GaON) and indium oxide (In₂O₃). A 250 °C Plasma-Enhanced Atomic Layer Deposition (PE-ALD) process was used to modulate defect configurations by tuning the O₂/NH₃ flow ratio, and the resulting optical properties were systematically analyzed with X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) spectroscopy. The results show that aggregated oxygen vacancies generate a quasi-continuous defect band spanning a spectral range from 400 to 800 nm. When combined with indium–tin oxide (ITO) and Ga-doped ZnO (GZO) transparent conductive layers and a Fabry–Perot resonant-cavity design, the overall emission spectrum can be extensively tailored. In ~10 nm-thick GaON films, pronounced many negative differential resistance (NDR) was observed,this behavior is attributed to tunneling effects and was verified by AFM measurements on devices with different substrate architectures. Large film thicknesses, a single NDR peak is shown to be related to vacancy-mediated carrier capture-and-release–induced luminescence in summary. These findings elucidate the white-light emission mechanism and defect spectra of wide-band-gap GaON and In₂O₃ color-center devices, offering an expanded palette of full-color spectral options. This thesis is organized into five chapters. Chapter 1 provides an introduction to LEDs, outlines the research motivation, and presents the overall framework of the dissertation. Chapter 2 details the luminescence mechanisms of LEDs, focusing on the color-center emission process examined in this work and the associated Fabry–Perot cavity model. Chapter 3 describes the experimental equipment employed, including the sputtering system and the plasma-enhanced atomic layer deposition (PE-ALD) system. Chapter 4 explains the device fabrication procedures and the characterization of the transparent conductive films. Chapter 5 discusses the comprehensive measurement setup and analyzes the collected data to verify the validity of the study. The final section offers conclusions and future prospects, aiming to advance the development of white-light LEDs based on the proposed structure.