由於石墨烯奈米結構為近年來非常熱門的材料，但現行半導體製造多以矽為主，矽烯奈米結構研究將有助於降低製造廠轉換製成的成本，所以矽烯奈米結構研究也越發熱門。本研究探討鋸齒狀矽烯奈米帶(ASiNRs)一維材料，吸附鹼金屬與鹵素原子的能帶結構。我們發現，將寬度為十二的ASiNRs，吸附鹼金屬鋰、鈉、鉀、銣與鹵素氟、氯、溴、碘等八種原子，吸附濃度到達16.67% ，為使系統吸附原子後，結構不彎曲的最大濃度。鹼金屬:鋰、鈉、鉀、銣最佳吸附位子在，矽原子蜂巢狀結構正中心上方處(Hollow)；而鹵素:氟、氯、溴、碘最佳吸附位子在，較高的矽原子正上方處(Top)。而隨著吸附鹼金屬與氟原子的電荷轉移的現象，打開了ASiNRs吸附系統的金屬性；吸附氯、溴和碘，則呈現半導體特性。呈現金屬性的載子分為兩類。吸附鹼金屬原子的系統，載子為電子；吸附氟原子的系統，載子為電洞。透過電荷轉移的現象知，鹼金屬與滷素等吸附原子，跟矽的鍵結絕大部分以離子鍵型式呈現；而彼此軌域重疊的部分，說明有少部分來自於共價鍵的鍵結貢獻。

Despite the popularity of grapheme research in recent years, silicon is still the main material used in current semiconductor industries. From a more industrial point of view, the research on silicon based nanostructure paves a more practical development path for doth compatibility and economic reasons. The electronic structures of ASiNRs adsorbed with alkali metals and halogen elements are studied using the density functional theory based on screened exchange local density approximation method. The most preferable adsorption sites are found to be hollow and top sites for alkali metals and halogen elements, respectively. As the ASiNRs remains completely flat, the maximum concentration of adsorption can reach 16.67%. All the relaxed systems with adsorbed atoms exhibit metallic or semiconducting behavior with strongly bonded Li, Na, K, Rb or F, Cl, Br, I atoms accompanied by an appreciable electron transfer from the Li, Na, K, Rb adatom to silicene nanoribbons or from the silicene nanoribbons to the F, Cl, Br, I. There are two types of charge carriers for the purpose of conducting. For the system with the alkali metals, the electrons work as the charge carrier. As to the system with halogen elements, the charge carriers are the electron holes. From the study on charge transfer, the adatoms can mostly bond with silicon by ionic bonds. Evidently, the valence bonds have their minor contributions due to the overlapping of orbital.
Keywords: alkali、halogen、ASiNRs

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