本研究利用反應式磁控共濺鍍系統製備不同的Ta-N、Ti-N單層奈米薄膜以及更兼具兩者特性的Ta-Ti-N三元複合薄膜，藉由改變氮氣流量與濺鍍靶材功率等製程參數，來討論不同薄膜微結構、形貌、成分對電阻率及電阻溫度係數之影響與關係。在實驗上藉由控制金屬靶功率、材料，並通入不同的氮氣流量比進行薄膜沈積。完成後將其以低掠角X光繞射儀分析其微結構與結晶相；以掃描式電子顯微鏡觀察表面形貌；以能量散佈光譜儀檢測薄膜化學成份；最後將其以四點探針與膜厚量測計算薄膜電阻率，並將四點探針結合加熱平台以測量電阻溫度係數。
實驗結果顯示，此薄膜的基本結構組成為α-Ta和β-Ti，金屬薄膜的厚度會隨製程參數變化，氮氣比例的增加與靶材功率降低會令沉積速率減少。而電阻率與電阻溫度係數會與材料的結構與性質有決定性的因素，大致來說隨著氮氣流量比的上升電阻率會增加。但是Ta-N薄膜在氮氣流量比為20%左右時，由於其微結構處於正在轉換類非晶－奈米晶粒的結構，其表面形貌相對緻密且電阻值較高。為使其得到改善，這邊使用共鍍的方式下結合兩種金屬Ta與Ti，使多晶沉積結構趨向穩定。總體而言，對薄膜性質的主要影響為薄膜成分與結構的改變，而氮氣流量比可做為控制薄膜成分的重要參數，在有穩定的電阻值及較低電阻溫度係數時，預期可應用薄膜電阻領域上。而相對具較高的負電阻溫度係數薄膜則適合應用在溫度感測器的元件上。
關鍵字：氮化鉭、氮化鈦、鉭-鈦-氮奈米複合薄膜、電阻溫度係數、薄膜電阻器、感測器。

Binary transition-metal nitride coatings such as tantalum nitride (Ta-N) and titanium nitride (Ti-N) have been attracted much attention because of its low resistivity, high thermal stability, high hardness, and corrosion resistance. It has a variety of wide applications such as diffusion barrier and resistor in micro and optoelectronics, cutting tools and heat-resistant layer in mechanical industry. The combination of Ta-N and Ti-N is expected to create a range of multi-functional materials in different compositions. Moreover, the combination of Ti in Ta-N thin film with the possibility to adjust the electrical property has been a great benefit to resistors and sensors by some controlled the related sputtering condition. In this present work, a series of transition nitride metal (Ta-N) and alloys (Ta-(Ti)-N) nanocomposite thin films were deposited by DC magnetron sputtering. The microstructure, composition, morphology and electrical properties of Ta-Ti-N films were characterized by using X-ray diffraction and Energy dispersive spectroscopy. The microstructures of the Ti-Ta alloys are based on bcc α-Ta and bcc β-Ti. In addition, the Ta-N structure showed clearly the qusi-amorphous structure with N2 flow ratio of 20%. However, the Ta-Ti-N is preferred to form polycrystalline phase at high nitrogen flow rates up to 20%. The results showed that Ta-Ti-N film at high FN2% possessed a high resistivity and high negative coefficient of resistance (N-TCR), which may be recognized as the best properties for application in thermally based micro sensors. Ta-Ti films which can precisely control the electrical property may be suitable for thin-film resistor.

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