| 摘要: | 近年來，Co-Ni薄膜和微粒被發現在感測器、先進微米電磁鐵以及磁性記憶體等方面的有相當大的應用潛力。然而在不同ㄧ維長度以及成分比例之鎳-鈷合金奈米線研究方面還沒有被深入探討。為了以低廉的成本快速製作大範圍且孔徑可控制的Co-Ni合金奈米線陣列，我們採用了ㄧ種有效且經濟的技術-氧化鋁 (AAO)模板法配合電鍍製程技術取代傳統的半導體微影技術。 在本研究中我們成功的透過控制參數的改變製備了具有二維有序孔洞結構的氧化鋁模板和大範圍整齊均ㄧ且具有不同鎳與鈷組成比例的Co-Ni合金奈米線陣列。氧化鋁模板的孔徑大小可控制調變在20-100 nm以及厚度在40-130 μm之間。在以直流電電鍍製程製備合金奈米線並移除氧化鋁模板後，我們成功的製作了高密度且具有不同組成(Co:Ni=1:9, Co:Ni=1:1, Co:Ni=9:1)的Co-Ni合金奈米線。從能量散佈分析儀的線掃描分析中顯示了這些合金奈米線完全是由鈷與鎳組成，並且在不同的樣品中會具有所需的鎳與鈷組成。在穿透式電子顯微鏡以及選區繞射的分析中，我們發現這三種組成的奈米線均為單晶結構且為六方晶系。Co-Ni合金奈米線的成長方向經鑑定後分別為:樣品A(Co:Ni=1:9)為[1 11]，樣品B(Co:Ni=1:1)為[ 41]，樣品C(Co:Ni=9:1)為 [ 41]。此外，實驗中我們也發現Co-Ni奈米線對外加磁廠的變化有很明顯的感應。本研究中我們利用了特定的外加磁場方向，可控制Co-Ni奈米線在矽基材上製備出具有二維方向排列合金奈米線陣列的圖形。 Recently, Co-Ni alloy thin film and particles have already been found their potential applications in sensors, advanced micoactuators, and magnetic recording medias. However, the synthesis and applications of one-dimensional (1-D) Co-Ni alloy nanowires with different contents have not been intensively studied. To fabricate large-area size-tunable Co-Ni alloy nanowire array at low-cost, an effective and economical technique-anodic alumina oxide (AAO) template-assisted electrodeposition process is one of the most promising schemes to replace the conventional lithography methods. In the study, we demonstrated that the AAO template with 2-D periodic nanopore structure and large-scale well-aligned Co-Ni alloy nanowire array with different composition ratio of Co and Ni were successfully fabricated under controlled synthesizing conditions. The pore diameter and lengths of the as-prepared AAO template can be tuned from 20-100 nm and 40-130 μm, respectively. After DC electrodeposition and subsequent removing the AAO templates, high-density, well-aligned Co-Ni alloy nanowires with different concentration ratio of Co to Ni(Co:Ni=1:9, Co:Ni=1:1, Co:Ni=9:1) were were successfully synthesizied. From the EDS line-scan profiles analysis, it is revealed that alloy nanowires were entirely composed of Co and Ni, and uniforem distributions of Co anf Ni throughout these nanowires. Based on the TEM and SAED analysis, it is found that the three sets of Co-Nialloy nanowires were all single crystalline, and these single crystalline Co-Ni nanowire possess a HCP structure. The growth direction of the Co-Ni alloy nanowires of samples A(Co:Ni=1:9), B(Co:Ni=1:1), and C(Co:Ni=9:1) were identified to be along the [1 11], [ 41], and [ 41] directions, repectively. On the other Hand, the Co-Ni nanowires were found to be very sensitive to the magnetic. In this study, we experimentally demonstrated that by applying external magnetic fileds, these Co-Ni nanowires can be controlled to align along the directions of applied magnetic filed and assemble into a 2-D ordered pattern on Si substrate. |
