Exploration of characteristics in the thin films of Zirconium oxide prepared by anodic oxidation met
蘇家慧、胡永柟、柯鴻禧
E-mail: [email protected]
ABSTRACT
It has been years that in semiconductor integrated circuit manufacturing, people have successfully used SiO2 as gate dielectric material in MOSFET and other related device. Recently, due to the improvement of semiconductor technique, the size of device has been reducing in order to increase the density of integrated circuit device greatly. For example, one of the techniques is to do shrink by Moore’s Law. Nowadays, by applying metal-oxide-semiconductor, the device can be reduced to nanometer. However, because of the small size of device, the thickness of gate oxidation layer will be reduced which will cause tunneling effect. The leakage current will increase and the characteristic of device will be poorer. For solving the problem of small size of device and the leakage current, the research of high-k material has been updated. The surface morphology of zirconium oxide films was measured by atomic force microscope (AFM), the thickness of oxide film observed from the transmission electron microscopy (TEM), the grown oxide films of which thickness, stacked layers’ structure, grain size and surface roughness (Ra) vary with oxidation time. Observing from the microscopic point of view, the nuclei of zirconium oxide started growing from the bottom (substrate surface) and gradually stacking up into a tetrahedral shape. The steep-grown tetrahedral are squeezed by 3D image processing. The resemble patterns show mainly square and rectangle shapes of which size are growing larger with increasing oxidation time. The crystal structure, showing
tetrahedral according to the measurement, seems unrelated to the oxidation time, but the binding energy of Zr3d, measured on surface and depths of the oxidation films by X-Ray Photoemission spectra (XPS), increase with oxidation time. This study, therefore, focuses on the research of gate oxide layer producing technique.
Keywords : Zirconium, anodic oxidation, atomic force microscopy, tetrahedral Table of Contents
封面內頁 簽名頁 摘要………
………… iii ABSTRACT………
……… iv 致謝………
v 目錄……… vi 圖目 錄……… viii 表目錄…
……… x 第一章 緒論 1.1 研究背景………1 1.2研究方 法………3 1.3論文結構……
………4 第二章 文獻回顧 2.1半 導體製程中高介電材料的介紹………5 2.2溶膠－凝 膠法製備二氧化鋯薄膜之物性和電性研究………8 2.3溶膠－凝膠法製 備之二氧化鋯薄膜其化學組成相依之微結構及電子結構之研究………9 2.4應用於先進互補式金氧 半電晶體具高功函數差與優異熱穩定性之金屬／高介電係數介電層閘極研究………12 2.5高介電係數金氧半電晶體及 低溫多晶矽薄膜電晶體之閘引發汲極漏電流及偏壓溫度不穩定性可靠度之研究……13 2.6氧化鉿薄膜電氣特性與結晶結構 之研究與探討………15 第三章 陽極氧化法應用於鋯氧化之研究 3.1實驗規劃………18 3.2穿 透式電子電子顯微鏡之量測與分析………20 3.3氧化鋯 薄膜表面輪廓特徵之探討………27 3.4氧化鋯薄膜 之電容－電壓特性………44 3.5氧化鋯薄膜之電 流－電壓特性………46 3.6氧化鋯薄膜之磁滯特 性………47 第四章 結論與未來研究方向 4.1結論………52 4.2未 來研究方向………54 參考文獻…
……… 55 圖目錄 圖3.1（a1
）陽極氧化5分鐘的TEM剖面影像堆疊結構分析圖………21 圖3.1（a2）陽 極氧化5分鐘的電子繞射圖……… 21 圖3.2（a1）陽極氧 化10分鐘的TEM剖面影像堆疊結構分析圖……… 22 圖3.2（a2）陽極氧化10 分鐘的電子繞射圖………23 圖3.3（a1）陽極氧化15分鐘 的TEM剖面影像堆疊結構分析圖……… 23 圖3.3（a2）陽極氧化15分鐘的電 子繞射圖………24 圖3.4（a1）陽極氧化20分鐘的TEM剖 面影像堆疊結構分析圖……… 25 圖3.4（a2）陽極氧化20分鐘的電子繞射圖
………25 圖3.5 氧化鋯與二氧化矽薄膜成長曲線圖………
……… 26 圖3.6（a） 陽極氧化5分鐘二維原始量測圖………
……… 28 圖3.6（b） 陽極氧化5分鐘經由軟體做輾平操作後的量測圖…
……… 29 圖3.7 陽極氧化5分鐘經輾平操作的二維圖形製作成三維圖形………
………29 圖3.8（a） 陽極氧化10分鐘二維原始量測圖………
………30 圖3.8（b） 陽極氧化10分鐘經由軟體做輾平操作後的量測圖………
………31 圖3.9 陽極氧化10分鐘經輾平操作的二維圖形製作成三維圖形………
……… 31 圖3.10（a）陽極氧化15分鐘二維原始量測圖………
………32 圖3.10（b）陽極氧化15分鐘經由軟體做輾平操作後的量測圖………
………33 圖3.11 陽極氧化15分鐘經輾平操作的二維圖形製作成三維圖形………
…………33 圖3.12（a）陽極氧化20分鐘二維原始量測圖………
……34 圖3.12（b）陽極氧化20分鐘經由軟體做輾平操作後的量測圖………
…34 圖3.13 陽極氧化20分鐘經輾平操作的二維圖形製作成三維圖形………35 圖3.14（a）陽極氧化5 min氧化鋯薄膜經輾平操作後微觀圖形……… 36 圖3.14
（b）陽極氧化10 min氧化鋯薄膜經輾平操作後微觀圖形………36 圖3.14（c）
陽極氧化15 min氧化鋯薄膜經輾平操作後微觀圖形………37 圖3.14（d）陽極 氧化20 min氧化鋯薄膜經輾平操作後微觀圖形………37 圖3.15（a）陽極氧 化5min氧化鋯薄膜晶體成長三維紋路圖形………38 圖3.15（b）陽極氧 化10min氧化鋯薄膜晶體成長三維紋路圖形……… 39 圖3.15（c）陽極氧 化15min氧化鋯薄膜晶體成長三維紋路圖形……… 39 圖3.15（d）陽極氧 化20min氧化鋯薄膜晶體成長三維紋路圖形……… 40 圖3.16 陽極氧化鋯薄膜表 面（5 20 min）Zr3d（3／2），Zr3d（5／2）X－光電子頻譜………43 圖3.17 氧化鋯薄膜電容－電壓 特性曲線圖………45 圖3.18 氧化鋯薄膜電流－電壓特性曲 線圖………46 圖3.19（a）氧化5分鐘所成長氧化鋯薄膜之 遲滯曲線圖……… 48 圖3.19（b）氧化10分鐘所成長氧化鋯薄膜之遲滯 曲線圖………49 圖3.19（c）氧化15分鐘所成長氧化鋯薄膜之遲滯曲線 圖………9 圖3.19（d）氧化20分鐘所成長氧化鋯薄膜之遲滯曲線圖……
………50 表目錄 表3.1長晶顆粒高度與成長時間之關係………
………27 表3.2電容值介電常數等效厚度的比較………
………45 表3.3陽極氧化鋯樣本崩潰電場與洩漏電流之關係………
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