本論文乃以脈衝雷射在矽 (111)基板沉積HfNbTaTiZr高熵合金薄膜，並探討所備製高熵合金薄膜之機械及電化學特性。薄膜成長及處理條件有四個變數，即雷射功率大小、沉積薄膜時間、雷射鍍膜之基材溫度及薄膜退火溫度。
HfNbTaTiZr高熵合金薄膜之機械性質係以奈米壓痕測試其奈米硬度及楊氏模數。X射線光電子光譜分析所製備之HfNbTaTiZr薄膜成分。高熵合金薄膜之電化學性質在選用HCl溶液，分別以循環伏安及交流阻抗測試薄膜之電化學特性。以原子力顯微鏡觀察分析所備製薄膜之表面形貌及表面粗糙度變化。高熵合金薄膜顯微結構及表面形貌則以場射掃描式及穿透式電子顯微鏡深入分析。
研究結果顯示，原子力顯微分析常溫下成長之HfNbTaTiZr薄膜表面粗糙度在0.31- 0.36 nm間，退火後及加溫成長之試片，薄膜表面粗糙度皆較高。奈米壓痕測試所備製之高熵合金薄膜試樣，常溫下成長2小時，其測得硬度及彈性模數與矽基材雷同；而成長3小時之試片可測得薄膜硬度及彈性模數值分別為10.96 GPa及107.92 GPa，此硬度值比塊材型態之HfNbTaTiZr高約三倍。電化學測試結果顯示在0.3 M HCl溶液測得之薄膜循環伏安電流密度值低，其交流阻抗測試所得之電荷傳導阻抗 (Rct)比AISI 304不銹鋼大，意謂在此溶液中，HfNbTaTiZr薄膜比AISI 304不銹鋼更耐蝕，且具兩串聯Randle電路；而在0.5 M HCl溶液測試，其電流密度值比在0.3 M HCl溶液中提升105倍，其交流阻抗測得之Rct反而比AISI 304不銹鋼小。顯微結構分析中，由TEM繞射圖可見，常溫成長之HfNbTaTiZr薄膜具BCC結構，且經退火後其結構不變；而在加溫情況下製備之薄膜，由於與大量氧反應，形成氧化物而為非晶結構。

In this dissertation, high-entropy-alloy HfNbTaTiZr thin films were prepared on the Si (111) substrate by pulsed laser deposition (PLD). Four parameters were conducted for the growth including PLD power, deposition time, substrate temperature, and post annealing treatment. The mechanical and electrochemical properties of HfNbTaTiZr thin films were studied by nano-indenter, cyclic voltammetry scanning and alternate current impedance. Surface morphologies and roughness values of HfNbTaTiZr thin films were examined by scanning electron microscopy and atomic force microscopy. Microstructures of HfNbTaTiZr films were characterized by transmission electron microscopy (TEM) equipped with energy-dispersive x-ray spectroscopy (EDS).
Experimental results show that surface roughness (Sq) values of HfNbTaTiZr thin films prepared with different PLD powers are between 0.32 and 0.36 nm which are even lower Si (111) substrate of 0.47 nm. A relatively high surface roughness was detected on the films prepared at higher temperatures and with annealing treatment. Based on the nano-indention measurement, Young’s modulus and nano-hardness values of with PLD within 2 hrs are closed to Si. However, Young’s modulus and nano-hardness value of HfNbTaTiZr films in 3-hour deposition are 10.96 GPa and 107.92 GPa, respectively. The hardness of HfNbTaTiZr thin film is about three-time higher than the as-cast HfNbTaTiZr bulk specimen. From the results of TEM and EDS, HfNbTaTiZr films grown at room temperature and after annealing show the BCC structure and have the high composition of oxygen.
Moreover, the results of electrochemical tests show that a very low current density of few 10-6 mA/cm2 by cyclic voltammetry scanning test in the 0.3 M HCl solution. The charge transfer resistance values of HfNbTaTiZr/Si are higher than those of austenitic stainless steel (AISI 304) and copper foil. This indicates that the corrosion resistance of HfNbTaTiZr/Si specimen is better than that of AISI 304 in the 0.3 M HCl solution. The Nyquist plots also show two parallel connections of Randle’s circuits in the same solution.

第1章 緒論 1
1.1. 前言 1
1.2. 高熵合金 2
1.3. 高熵合金的效應及應用 3
1.4. 以脈衝雷射沉積成長高熵合金薄膜 5
1.5. HfNbTaTiZr高熵合金薄膜 6
1.6. 高熵合金之電化學測試 7
1.7. 高熵合金之顯微組織分析 11
1.8. 高熵合金之機械性質分析 14
第2章 研究動機 19
第3章 實驗儀器 21
3.1. 薄膜備製 21
3.1.1. 脈衝雷射沉積 (PLD) 21
3.1.2. 準分子雷射 24
3.1.3. 電化學 25
3.2. 薄膜分析 27
3.2.1. 掃描式電子顯微鏡 (SEM) 27
3.2.2. X射線能量散佈光譜儀 (EDS) 28
3.2.3. X-射線光電子光譜 (XPS) 30
3.2.4. X射線繞射儀 (XRD) 32
3.2.5. 原子力顯微鏡 (AFM) 35
3.2.6. 奈米壓痕 (Nano Indenter) 37
3.2.7. 穿透式電子顯微鏡 (TEM) 40
3.2.8. 雙束型聚焦離子束系統 (FIB) 41
第4章 實驗 43
4.1. 靶材製備 43
4.2. PLD 雷射鍍膜系統操作程序 44
4.2.1. 填充雷射氣體 44
4.2.2. 建立真空環境 44
4.2.3. 置放試片 45
4.2.4. 取出試片 45
4.3. 電化學測試 46
4.4. PLD實驗參數 47
第5章 結果與討論 49
5.1. 雷射功率與能量大小之測試結果 49
5.2. A系列 改變成長功率 51
5.2.1. SEM 觀察分析 52
5.2.2. AFM表面形貌分析 53
5.2.3. Nanoindenter 55
5.2.4. XRD量測 56
5.2.5. XPS圖譜 57
5.2.6. A系列結論 60
5.3. B系列 改變PLD鍍膜時間 61
5.3.1. SEM觀察分析
5.3.2. AFM表面形貌分析 63
5.3.3. Nanoindentor 65
5.3.4. XRD量測 66
5.3.5. XPS圖譜 67
5.3.6. B系列結論 71
5.4. C系列 改變退火溫度 72
5.4.1. SEM觀察分析 73
5.4.2. AFM表面形貌分析 74
5.4.3. Nanoindentor 76
5.4.4. XRD量測 77
5.4.5. XPS圖譜 78
5.4.6. TEM 82
5.4.7. C系列結論 86
5.5. D系列 改變成長溫度 87
5.5.1. XRD量測 88
5.5.2. AFM表面形貌分析 89
5.5.3. 電化學測試 91
5.5.4. 交流阻抗測試 101
5.5.5. TEM 105
5.5.6. D系列結論 111
第6章 結論 113
第7章 參考文獻 115

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