Silicon nanowires prepared by thermal evaporation and their photoluminescence properties measured at low temperatures
Pham, Van Tuan; Le, Van Ngoc; Chu, Anh Tuan; Pham, Toan Thang; Tran, Ngoc Khiem; Pham, Hong Duong; Pham, Thanh Huy; Pham, Van Tuan; International Training Institute for Materials Science, Hanoi University of Technology, 1 Dai Co Viet Road, Hanoi, Vietnam; Le, Van Ngoc; Institute of Engineering Physics, Hanoi University of Technology, 1 Dai Co Viet Road, Hanoi, Vietnam; Chu, Anh Tuan; Institute of Materials Science (IMS), Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Hanoi, Vietnam; Pham, Toan Thang; Hanoi Advanced School of Science and Technology, Hanoi University of Technology, 1 Dai Co Viet Road, Hanoi, Vietnam; Tran, Ngoc Khiem; International Training Institute for Materials Science, Hanoi University of Technology, 1 Dai Co Viet Road, Hanoi, Vietnam; Pham, Hong Duong; Institute of Materials Science (IMS), Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Hanoi, Vietnam; Pham, Thanh Huy; Hanoi Advanced School of Science and Technology, Hanoi University of Technology, 1 Dai Co Viet Road, Hanoi, Vietnam
Журнал:
Advances in Natural Sciences: Nanoscience and Nanotechnology
Дата:
2011-03-01
Аннотация:
In the present work, silicon nanowires were prepared by a thermal evaporation method. The evaporating source was a mixture of silicon and carbon nanopowders. Surface morphology, structural characteristics and emission properties of the silicon nanowires were investigated by several techniques. The results showed that the obtained products have the shape of nanowires with diameters ranging from 30 to 120 nm and lengths from 300 to 400 nm. The x-ray diffraction (XRD) patterns confirmed the presence of crystalline silicon. Transmission electron microscope (TEM) images revealed the core-shell structure of the wires. In the photoluminescence (PL) spectra recorded at room temperature, only a broad emission band peaking at about 650 nm was observed. In addition to the red emission, two other bands centered at around 455 nm and 510 nm appeared when measured at low temperatures. The origin and emission mechanism of these bands are discussed.
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