現今薄膜機械性質分析，多著重於硬度、彈性系數和附著性質等，而薄膜在製作或是使用過程中若產生破裂，會嚴重影響薄膜性能，因此破裂韌性(fracture toughness)亦為薄膜相當重要的機械性質之一，能進一步瞭解並且分析破裂韌性可避免薄膜結構上的損害。近年來，有鑑於金屬玻璃薄膜(thin film metallic glass, TFMG)擁有許多獨特性質，高強度、耐腐蝕和光滑之表面，而引起各界重視，並被嘗試應用於各領域，然而將金屬玻璃薄膜應用於產品上的研發，除基本機性質了解外，若能進一步瞭解金屬玻璃薄膜的破裂韌性，勢必能更加完整的發揮其優越性並作為相關應用的薄膜選用依據。本研究使用射頻磁控濺鍍儀製備鋯基和鎢基金屬玻璃薄膜於矽基板，再以雙束型聚焦離子束將基材上之金屬玻璃薄膜製作成微米尺度懸臂樑，接著利用奈米壓痕儀對金屬玻璃懸臂予以樑壓，進行缺口破裂韌性(Notch Toughness, KQ)實驗分析計算，同時與傳統結晶之氮化鈦(TiN)薄膜、鈦(Ti)金屬薄膜以及具有與鋯基金屬玻璃薄膜相似成份組之鋯基金屬塊材成進行比較，以探討各材料破裂韌性之相互關係。經懸臂樑缺口破裂韌性測量結果發現，氮化鈦的KQ值為0.74 MPa*m0.5，實驗結果與壓痕破裂韌性實驗所計算出的值相當接近，故懸臂樑破裂韌性實驗應具有其一定的準確性。而經懸臂樑破裂韌性實驗計算出鋯基金屬塊材、鋯基和鎢基金屬玻璃薄膜之KQ值分別為4.4 MPa*m0.5、3.84 MPa*m0.5和5.13 MPa*m0.5，高於Ti (2.15 MPa*m0.5)及氮化鈦薄膜，符合文獻中指金屬玻璃薄膜具優良機械性質的特性，顯示本研究所用使用之試驗法的可行與應用性。此外，金屬玻璃薄膜在使用壓痕破裂韌性法上不見其產生裂痕，故無法藉此法計算金屬玻璃薄膜之破裂韌性值，因此凸顯出本研究之懸臂樑試驗法對量測金屬玻璃薄膜之破裂韌性值的重要性。

Analysis of mechanical properties on thin films usually focus on the hardness, elastic modulus and adhesion behavior. One of the key mechanical properties on thin film is the fracture toughness, which directly affect the application. Therefore, understanding and evaluation the fracture toughness of thin film is an important issue. Metallic glass thin films (TFMGs) have many unique properties, high strength, corrosion and smooth surface. They attract many attentions in the industry and has been researched and developed for various application. Nevertheless, studies on fracture toughness of TFMGs were still insufficient in recent year. Therefore, this study measured the fracture toughness of amorphous Zr51Cu31Al13Ni5 and W33Ni32B35 TFMGs in comparison with crystalline Ti and TiN thin films as well as bulk metallic glass (BMG) using microcantilever deflection and conventional indentation methods. Deflection testing was conducted using microcantilevers fabricated by focused ion beam machining. Higher notch toughness values of 4.4, 3.84 and 5.13 MPa*m0.5 for BMG, Zr- and W-based TFMGs, respectively, than TiN (0.74 MPa*m0.5) and Ti (2.15 MPa*m0.5) films were obtained. The notch toughness of amorphous materials far exceeded those of crystalline materials. Zr-TFMG and BMG microcantilevers presented ductile fracture behavior similar to that of Ti. The results of fracture energy and vein pattern size would appear to be better than notch toughness values for the evaluation of fracture behavior. Zr-TFMG was shown to require more energy for the creation of fractures than were the other materials. Therefore, at micro-scales, metallic glasses present relatively better fracture behavior than do crystalline materials. This study presents a direct comparison of works related to the notch toughness of amorphous and crystalline materials.

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