本研究為使用分子束磊晶系統(Molecular Beam Epitaxy, MBE)透過在五環素(pentacene)薄膜中摻雜少量鐵磁性的鎳(Ni)原子，來了解有機磁性半導體的鐵磁特性，並以加熱器改變薄膜成長時的基板溫度，進一步探討成長溫度改變對Ni摻雜的pentacene薄膜造成的影響。由實驗結果，發現有機磁性半導體在室溫(27 ℃)之下可具有鐵磁滯曲線；而一般無機半導體摻雜鐵磁性原子，需在低溫下才具有鐵磁滯曲線，這表示在有機半導體pentacene與鐵磁性原子Ni間有很強的自旋耦合(spin-coupling)量子效應。
實驗顯示pentacene薄膜的成長與薄膜成長時的基板溫度有關。隨著成長溫度的上升pentacene薄膜之晶相會由薄膜相(thin-film phase)逐漸轉化成塊材相(bulk phase)，而在摻雜Ni原子的pentacene薄膜之晶相均維持為薄膜相，推測可能是pentacene的分子排列因Ni的摻雜被鎖住，導致僅在高溫時會有少量的塊材相出現。且在有無摻雜Ni的pentacene薄膜表面之晶粒大小均會隨著成長溫度變高而變大、晶粒與晶粒間的距離也會成長溫度升高而變寬。
並觀察到Ni摻雜的pentacene薄膜，在經外加水平磁場後表面可觀察到較明顯的磁訊號，且經薄膜表面電位會有變大的現象發生。由偏振拉曼(Raman)光譜得知外加磁場可提高Ni摻雜的pentacene薄膜中pentacene分子與分子間的耦合程度，且隨這薄膜成長溫度越高耦合度越佳。還發現當鐵磁性的pentacene薄膜成長時的基板溫度由50℃上升至75℃時，磁滯曲線的飽和磁矩會變大、殘留磁矩和矯頑力均變小，可能是受到薄膜微結構或pentacene分子的π電子雲與Ni的3d軌域的自旋電子之間的交互作用(exchange interaction)所影響，其詳細物理機制在本文中有深入探討。

Magnetic organic semiconductor thin films composed of pentacene molecules and a small amount of ferromagnetic Ni atoms were fabricated via molecular beam epitaxy under different deposition temperatures. The organic magnetic semiconductor had a remarkably ferromagnetic hysteresis curve at room temperature, which indicated that there is a strong spin-coupling between pentacene molecules and Ni atoms. The growth of the pentacene film was related to the substrate temperature at which the film was deposited. After the Ni-doped pentacene films were applied the horizontal magnetic field, magnetic signal on the surface of the films were more obvious through the observation of magnetic force microscopy. Through Raman spectroscopy analyses of Ni-doped pentacene films, we observed that the coupling degree between the each pentacene molecule increased with the external magnetic field, and the higher the growth temperature of the film resolved in the better the coupling degree. When the substrate temperature of the ferromagnetic pentacene films increased from 50 °C to 75 °C, the saturation magnetic moment became larger, and the residual magnetic moment and the coercive force became smaller. We thought that it may be affected by the microstructures of the film or the existence of electronic coupling between the π-electron cloud of pentacene molecules and 3d orbital electron of Ni atoms.

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