本論文利用磁控式共濺鍍系統，進行氧化銦鋅鎵四元素之氧化物合靶材與金屬鋁靶材之共濺鍍薄膜實驗，文獻中指出摻雜鋁於氧化鋅系列導電膜及半導體有助於提升薄膜載子濃度或者是導電率之特性，不過其與氧之高反應性卻往往使其成為載子傳輸時的障礙，因此本實驗將探討利用磁控式共濺鍍系統共濺鍍氧化銦鋅鎵及鋁。實驗結果證明利用鋁進行摻雜確實能夠提升薄膜之電傳導特性，其主因為薄膜中存在著較大外圍s空軌域之原子如銦或者是鋅，而俱較小外圍s空軌域之鋁摻入能夠增加s軌域之間的重疊範圍，此特性將增進載子傳輸效率使得載子移動率上升。實驗中首先將對薄膜做定性以及定量之成分確認，接著利用霍爾量測探討其電傳導特性之變化，並利用基本透明氧化物之傳導及鍵結特性以分析其電特性之變化，並利用X光繞射分析確認薄膜之結晶特性並無顯著變化，亦因未來可能之光電元件的應用，故亦將確認薄膜於近紅外光至可見光波段之穿透率特性；最後並利用摻鋁後所帶來之薄膜電特性變化應用於薄膜電晶體元件上，實驗結果證明摻鋁將使得薄膜更適於應用於薄膜電晶體元件之主動層。
　　本研究利用本實驗室之三靶共濺鍍氧化銦鋅鎵薄膜所得之最佳薄膜電晶體元件特性之通道層薄膜為本鋁摻雜實驗之基礎，於三靶共濺鍍實驗中，氧化銦射頻功率為50瓦、氧化鎵射頻功率25瓦及鋅直流功率10瓦，利用當中金屬元素之比例( In: Zn: Ga= 3.52: 2.72: 1)製作成一氧化銦鋅鎵合靶材以利與鋁靶材進行本共濺鍍實驗：實驗第一部分為調變製程中氧通入流量比例以調控薄膜電特性之變化，並以具最佳電傳導特性( 0% O2，載子濃度：1.76×1020 cm-3、導電率：6.67×102 S/cm及載子遷移率：2.33×101 cm2/V-s)及最適合應用於元件主動層之氧流量( 40% O2，9.97×1016　cm-3、1.32×10-1　S/cm及3.13×10-1　cm2/V-s)為基底，進行第二部分之不同射頻瓦數之共濺鍍鋁實驗，並利用X光能譜能量散射分析儀進行薄膜鋁含量之定性及定量分析，確認摻雜後薄膜中之銦、鎵和鋅三金屬比例與靶材之間並無明顯差異後方可進行比較。而於元件製作方面，首先將利用調變製程之氧流量使其之電流電壓特性與利用三靶共濺鍍所得之元件特性相近，由量測發現於通氧流量比例為40%時特性最為相近，此時之薄膜其載子濃度約1017cm-3，而此數量級之載子濃度和文獻中指出適合作為薄膜電晶體通道層薄膜之載子濃度相近，故元件製作實驗將利用此組氧流量作為摻鋁元件之基礎，並由薄膜分析確認薄膜中之金屬元素成分比例與利用三靶共濺鍍所得為相近，以利後續之不同瓦數摻鋁之比較，而實驗所得之最佳元件特性為製程氣體中氧氣比例40%及鋁射頻瓦數45瓦時，此時元件之場效載子移動率為170.25 cm2/V-s、臨界電壓為0.7V、電流開關比為7.81×106、次臨界擺幅為130mV/decade；另一方面，因氧化物半導體元件易因暴露於空氣中導致其元件特性易隨著時間而變化，因此亦比較無摻鋁與最佳化摻鋁瓦數之元件特性隨著時間增加其特性之比較，並嘗試利用濺鍍系統成長之氮氧化矽及原子層沉積系統成長之氧化鋁作為元件之表面護佈層，不過由實驗結果得知，無表面護佈之45瓦摻鋁之元件其穩定性最佳。

In this work, we reported the single quaternary oxide target, indium gallium zinc oxide co-sputtering with metal aluminum target by magnetron co-sputtering system. Literature showed that doping aluminum to the zinc oxide based transparent conducting oxide and semiconductor will increase either carrier concentration or conductivity. But aluminum with highly reactivity to the oxygen will become an obstacle during carrier transport. For that reason, we will investigate the method co-sputtering indium zinc gallium oxide and aluminum by using magnetron co-sputtering system. And the experimental result showed that doping via aluminum can really improve the electrical conductivity of the thin film. The reason is due to the atoms with larger outer most vacant s orbital existed in the film, like indium or zinc, and the doping of smaller outer most vacant s orbital will increase the overlapping region between s orbitals. This increased overlapping region will enhance the carrier transportation efficiency thus leading to the carrier mobility increment. During the experiment, we first did the qualitative and quantitative measurement to confirm the thin film composition. Later, we investigated the changes of electrical conductivity property by Hall-measurement then analyzed the changes of electrical property by ways used to analyze the basic transparent oxide, from conducting and bonding point of view. Then we utilized the X-ray diffraction measurement to confirm that there is no evident change between thin film crystallinity. And also for the possible application within optical-electronic device in the future, we confirmed the transmittance between the near infrared and visible region to ensure the transmittance property. Lastly, from the changes of the thin film electrical property caused by doping aluminum. We then applied this thin film to the thin film transistor and the results proved that via the doping process will make the thin film much more applicable to the active layer of thin film transistor.
This work utilized the optimized film which having the optimized thin film transistor performance got from co-sputtering indium zinc gallium oxide film as the basis for this aluminum doping experiment. In the co-sputtering experiment, we used three separate targets, the indium oxide with radio frequency power of fifty watts, gallium oxide with radio frequency power of twenty-five watts and zinc with direct current power of ten watts. We used the metal atomic ratio( In: Zn: Ga= 3.52: 2.72: 1) within the co-sputtered film to fabricate a mixed target in order to conducting this co-sputtering experiment with aluminum. The first part of this experiment was to tune the oxygen flow ratio to control the electrical property change of thin film, and used the result with optimized electrical transportation property( 0% O2，carrier concentration：1.76×1020 cm-3、conductivity：6.67×102 S/cm and carrier mobility：2.33×101 cm2/V-s) and most suitable for use in the active layer of device( 40% O2，9.97×1016　cm-3、1.32×10-1　S/cm及3.13×10-1　cm2/V-s) as the starting point to do the co-sputtering with various aluminum radio frequency power. After thin film deposition, we used the energy dispersive spectrometry to confirm qualitatively and quantitatively to the thin film, making sure that there is no clear atomic ratio difference between thin film and the target. And then came to the device fabrication, we first tuned the deposition oxygen flow ratio to make the current voltage characteristic close to those obtained from trinal target co-sputtering. And the result showed that under forty percent oxygen flow ratio, the device performance was the most alike to those obtained from trinal target co-sputtering. Under this oxygen flow ratio condition, the carrier concentration is about 1017cm-3, which is closed to the proposed carrier concentration that is suitable for use in the channel layer of thin film transistor. Later we confirmed that the metal element ratio between target and thin film were alike for reliably comparing with different aluminum co-sputtering power.
The final optimized device performance is under the deposition with forty percent oxygen flow ratio and aluminum radio frequency power with forty-five watts. And this device with field effect mobility of 170.25cm2/V-s, threshold voltage of 0.7V , current on/off ratio of 7.81×106 and subthreshold swing of 130mV/decade. On the other hand, due to the easy variable device property of oxide based semiconductor device when exposed to the air. So, the device property between aluminum un-doped and optimized aluminum doping power device with time were compared, and the device surface passivation formed respectively by sputtered silicon-oxide-nitride and atomic layer deposited aluminum-oxide was performed. And the experiment result showed that the device without surface passivation and with forty-five watts aluminum doping power behaved the best device stability.

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