One-dimensional (1D) nanostructures have been regarded as the most promising building blocks for nanoscale electronic and optoelectronic devices. Nd-doped silicon nanowires have been synthesized by a vapor transport and condensation method. The incorporation of neodymium within silicon nanowires was achieved by using NdCl3•6H2O powder as the doping source. Ferromagnetism and infrared photoluminescence at room temperature were observed for the first time. The significant variation and versatility of the properties exhibited by the Nd-doped silicon nanowires are promising for exploitation for the advanced silicon-based devices.
Silicon-germanium (Si1-xGex) nanowires have been grown by a simple vapor transport method. The growth was found to follow the vapor-liquid-solid mechanism. The composition of germanium in the Si1-xGex nanowires ranging from 0 to 0.55 ( 0＜x≦0.55) could be controlled by adjusting the ratio of Ge/Si source. The iodine source in this synthesis process was found to be critical in facilitating the reactions. Ferromagnetism at room temperature was observed by implanting the Mn ions with the dose of 2x1016 /cm2 at 200 KV.
One-dimensional In2Se3 nanobelts have been synthesized via a vapor-liquid-solid process. The I-V measurement demonstrated that the reversible phase transformation between the crystalline and amorphous state with the resistance ratio of about 102-104. The 1100 nm infrared photoemission was also observed by photoluminescence measurement. Both the electrical and optical properties suggested that the In2Se3 were viable as the building block for the state-of-the-art optoelectronics and phase change memory devices.

一維奈米結構是近來最受矚目的一個研究方向，除了物質在奈米尺度下所具有的特殊物理性質外，同時也是奈米元件的最小組成單元。本研究將重心放在一維奈米線的合成及摻雜的性質研究，涵蓋的範圍可區分為三個部分。第一部分為矽奈米線中摻入釹的稀土元素。釹摻雜的矽奈米線可利用水平爐管搭配氯化釹的粉末做為摻雜來源成功的合成出來。在性質方面除了稀土元素釹本身具有的1.3微米的放光外，室溫下釹摻雜的矽奈米線所具有鐵磁的行為也是首次被觀察到。此外，電阻率及場發射性質的量測間接的提供了釹元素摻雜入矽奈米線的證據。第二部分為矽鍺奈米線的合成，在本實驗中，首次發現利用碘的粉末搭配矽及鍺的反應物可成功的在爐管中成長出矽鍺奈米線，碘在整個反應過程中扮演著一個不可或缺的關鍵角色。此外，利用不同比例的矽與鍺粉末可用以控制所成長出的矽鍺奈米線的成分比例。而在性質方面，利用離子佈植的技術可將錳離子摻雜進矽鍺奈米線中，成功的合成並觀測到在室溫下具有鐵磁行為的錳摻雜矽鍺奈米線。不論是釹摻雜的矽奈米線或是錳摻雜的矽鍺奈米線，其於室溫下所具有的鐵磁行為，都是未來應用於自旋電子元件中相當具有潛力的材料。
最後一個部分為硒化銦奈米帶的研究。硒化銦是一個在相變記憶體上常被運用的材料，利用爐管以氣-液-固 (Vapor-liquid-solid)三相的方法可成功合成出具有超晶格結構的硒化銦奈米帶，將所合成出的奈米帶以離子束聚焦的方式把鉑鍍在奈米帶的兩端做為電極，再以電性設備進行觀測，利用調控不同的電流強度可控制奈米帶的結晶行為進而達到1及0的訊號控制。此外，在光學量測的部份，由於硒化銦奈米帶具有一個較窄的能隙，且載子傳輸可在一個維度方向上，在太陽能電池的應用上也是一個適當的選擇。

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