以脈衝雷射蒸鍍法於氧化鋅薄膜上成長氧化錳鋅薄膜

Pulsed Laser Deposition of MnZnO Thin Film on ZnO Films

盧奕誠(Yi-Cheng Lu)

指導教授 ： 洪魏寬

國立臺北科技大學/電資學院/光電工程系研究所/碩士(2010年)

摘要

本研究分為兩個部分，第一部分是使用脈衝雷射蒸鍍法於C面sapphire基板上蒸鍍MnxZn1-xO (0.04≦x≦0.2)薄膜，實驗中使用的靶材為自製靶材，依實驗目的調配不同成分，並觀察改變鍍膜壓力與溫度參數對MnxZn1-xO薄膜結構與光學特性的影響。利用掃描式電子顯微鏡(scanning electron microscope，SEM )與原子力顯微鏡(atomic force microscopy，AFM)觀察表面形象與粗糙度。以X光繞射儀( X-ray diffraction，XRD )觀察成長方向並利用穿透光譜定義吸收光譜以得到MnxZn1-xO薄膜能隙。
第二部分是使用脈衝雷射蒸鍍法，在C面sapphire基板上先蒸鍍氧化鋅薄膜，再於氧化鋅緩衝層上成長MnxZn1-xO (0.02≦x≦0.2)薄膜。透過SEM與AFM觀察Mn濃度與薄膜粗糙度的關係。從XRD發現只有(0002)繞射峰出現，表示MnxZn1-xO具有良好的方向性與結晶性，且峰值隨著Mn濃度增加而往小角度方向移動，代表晶格常數變大。由常溫下的光激螢光光譜(photoluminescence，PL)量測發現當Mn濃度增加可使進能帶區之紫外發光(UV luminescence) 峰值產生藍移，而半高寬(full width at half maximum，FWHM)也因摻雜而變寬。此外，本實驗能夠透過改變Mn的含量值來控制發光能隙，且能在常溫下發光。

關鍵字

脈衝雷射蒸鍍 ； 氧化鋅 ； 氧化錳鋅

並列摘要

MnxZn1-xO has become an attractive material because of it’s ferromagnetic and optoelectronic properties. Here we demonstrate that MnZnO thin film can be synthesized via pulsed laser deposition (PLD) method and investigate it’s structural and optoelectronic properties.
The thesis consists of two parts. In the first part, the MnxZn1-xO (0.02≦x≦0.2) thin film was grown on c-plane sapphire substrate by PLD method directly. Measurements include scanning electron microscope (SEM), X-ray diffraction (XRD), optical transmission spectra, and atomic force microscopy (AFM).
In the second part, in attempt to improve crystalline properties of MnZnO, the ZnO thin film was grown on c-plane sapphire substrate before the growth of MnZnO. The SEM images reveal the thin film structure become rougher when x increase. The XRD shows that only (0002) peak exists and the peak moves to lower angle( lattice constants become larger) . The room-temperature photoluminescence (RTPL spectrum) showed that ultraviolet luminescence peak has blueshift with the increasing Mn composition, and full width at half maximum (FWHM) of PL spectrum became wider. Besides, this thesis showed the bandgap of MnZnO can be controlled with Mn composition and the RTPL of MnZnO was observed.

並列關鍵字

PLD ； ZnO ； MnZnO

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