臺灣博碩士論文加值系統

本研究主要分為三大部分：第一部分係利用黏貼兩片銅的鋁靶沉積Cu-Al-O薄膜，討論氧分壓及基板溫度對薄膜光電性質的影響。第二部分則是在氧分壓5%，調整銅鋁複合靶的銅片數量以製備銅鋁比例接近的CuAlO2薄膜，並討論銅鋁比例接近條件下功率對於薄膜結晶相的影響。第三部分是以純銅靶分別沉積純銅及Cu2O薄膜於藍寶石基板(sapphire)上，接著以退火處理方式使薄膜和基板反應生成CuAlO2，並探討升降溫速率與退火環境對薄膜的影響。
沉積後或退火後的薄膜以電子微探儀做成份定量；低掠角X光繞射及掃瞄式電子顯微鏡進行薄膜結晶性與結構分析；導電性方面，利用四點探針及霍爾量測得到薄膜電阻率、載子濃度與載子遷移率。在光學性質方面，本研究以紫外光-可見光光譜儀，在可見光範圍下量測薄膜的穿透率。
第一部分的研究結果顯示，薄膜為CuO及Cu2O混合的結晶相，在氧分壓25%時，可得到最低的電阻率3.3 Ω-cm。研究發現氧分壓會影響薄膜中的鋁含量及薄膜中CuO及Cu2O的比例使薄膜電阻率改變。增加基板溫度，有助於提升薄膜結晶性及穿透率，但不利於導電度。第二部分研究中，於0.25片銅的條件下可以得到成份最接近CuAlO2的薄膜。功率為100 W時，薄膜仍為CuO及Cu2O的混合相；當濺鍍功率增加至200 W時則可得CuO及CuAlO2混合的結晶相，其電阻率為5.9 Ω-cm，穿透率可達74.9%。最後一部分的結果中發現Cu2O薄膜與sapphire基板在大氣下，1000℃以快速升降溫方式退火一小時可得單相CuAlO2。
本研究發現，在高氧分壓、低濺鍍功率及較慢升降溫之退火條件下，薄膜中主要的結晶相為CuO及Cu2O；在低氧分壓的條件下，提高薄膜濺鍍功率有助於CuAlO2結晶相的生成。以第三部分中快速升降溫退火的方式可以得到單相CuAlO2。

The study of p-type CuAlO2 thin film includes three parts. In the first part, the Cu-Al-O thin films were deposited by a Cu-Al composited target. The effects of oxygen ratio and substrate temperature on the electrical and optical properties of Cu-Al-O films were studied. In the second part, the oxygen ratio was controlled at 5% and the concentrations of sputtered films were adjusted by placing various Cu disks on the Al target surface. The effect of working power on crystallization of sputtered films as the film composition approach CuAlO2 was also studied. In the third part, the Cu and Cu2O films were deposited on the sapphire substrate by using a Cu target. The deposited films were than reacted with sapphire substrate as they were annealed at 1000℃ for 1 hr. The effects of heating/cooling rates and the gas atmosphere on films properties were studied.
The composition of deposited film was measured by the FE-EPMA WDS. The crystal structure and surface morphology were determined by GIAXRD and FE-SEM, respectively. The electrical properties, films resistivity, carrier concentration and carrier mobility were determined by 4-point probe and Hall measurement, respectively. The transmittance of the deposited film was measured by the UV-Vis in visible range.
The XRD result in the first part shows that the sputtered films were CuO/Cu2O mixture phase and the minimum resistivity is 3.3 Ω-cm as the film was deposited with oxygen ratio of 25%. It was found that the oxygen ratio affects the Al content and CuO/Cu2O ratio in the film which has important effect on film resistivity. The crystallinity and optical transmittance of the thin film increase with increasing substrate temperature. However, the electrical conductibility decreases with it. The second part of this study shows that the Al target with 0.25 disks is the optimum condition for preparing CuAlO2 films. Under the working power of 100 W, the deposited film was a CuO/Cu2O mixed phase. As the sputtering power increase to 200 W, a CuO/ CuAlO2 mixture phase can be found in XRD pattern. The measured resistivity and optical transmittance were 5.9 Ω-cm and 74.9%, respectively. In the last part of the study, a single-phased CuAlO2 can be prepared by a Cu2O film with rapid rate of annealing process at 1000 ℃.
The results show that CuO and Cu2O may be easily formed under high oxygen ratio, low working power and lower rate of annealing process. As the oxygen ratio lower than 10%, the increase of working power is benefit for the growth of CuAlO2 phase. In the third part, single-phased CuAlO2 can be prepared by rapid rate of annealing treatment.

第1章 緒論 1
1-1 前言 1
1-2 研究目的與動機 2
第2章 理論基礎 3
2-1 透明導電氧化物薄膜 3
2-1-1 導電性質 4
2-1-2 光學性質 5
2-2 CMVB理論 7
2-3 CuAlO2簡介 8
2-4 文獻回顧 9
第3章 實驗方法與步驟 20
3-1 實驗材料 20
3-1-1 靶材(target) 20
3-1-2 基材(substrate) 20
3-1-3 濺鍍氣體(sputtering gas) 20
3-2 實驗設備 21
3-2-1 真空濺鍍系統 21
3-2-2 真空退火爐 21
3-3 實驗方法 22
3-3-1 銅鋁複合靶材製備 22
3-3-2 基材清洗 22
3-3-3 薄膜製備 22
3-4 薄膜性質分析 24
3-4-1 薄膜厚度量測 24
3-4-2 高解析度場發射電子微探儀(Field emission electron probe X-ray Micro analyzer, FE-EPMA) 24
3-4-3 低掠角X光繞射(Glancing incident angle XRD, GIAXRD)分析 25
3-4-4 掃瞄式電子顯微鏡(scanning electron microscope, SEM)分析 26
3-4-5 四點探針(4-point probe)量測 27
3-4-6 霍爾效應量測 (Hall effect measurement) 27
3-4-7 光學性質量測 28
第4章 結果與討論 36
4-1 製程條件對濺鍍速率的影響 38
4-2 氧分壓與基板溫度對薄膜性質的影響 40
4-2-1 場發射電子微探儀(FE-EPMA WDS)定量分析 40
4-2-2 薄膜微結構分析 42
4-2-3 薄膜導電性質量測 45
4-2-4 薄膜光學性質量測 48
4-3 鋁含量對薄膜性質的影響 49
4-3-1 場發射電子微探儀(FE-EPMA WDS)定量分析 49
4-3-2 薄膜微結構分析 51
4-3-3 薄膜導電性質量測 54
4-3-4 薄膜光學性質量測 56
4-4 異質界面反應 58
4-4-1 成份分析 58
4-4-2 微結構分析 60
4-4-3 光電性質分析 61
4-4-4 薄膜退火處理 62
第5章 結論 103
第6章 未來工作 104
參考文獻 105

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