Broadband infrared photoluminescence in silicon nanowires with high density stacking faults

Nanoscale ◽  
2015 ◽  
Vol 7 (5) ◽  
pp. 1601-1605 ◽  
Author(s):  
Yang Li ◽  
Zhihong Liu ◽  
Xiaoxiang Lu ◽  
Zhihua Su ◽  
Yanan Wang ◽  
...  
1999 ◽  
Vol 595 ◽  
Author(s):  
A. Kvit ◽  
A. K. Sharma ◽  
J. Narayan

AbstractLarge lattice mismatch between GaN and α-Al2O3 (15%) leads to the possibility of high threading dislocation densities in the nitride layers grown on sapphire. This investigation focused on defect reduction in GaN epitaxial thin layer was investigated as a function of processing variables. The microstructure changes from threading dislocations normal to the basal plane to stacking faults in the basal plane. The plan-view TEM and the corresponding selected-area diffraction patterns show that the film is single crystal and is aligned with a fixed epitaxial orientation to the substrate. The epitaxial relationship was found to be (0001)GaN∥(0001)Sap and [01-10]GaN∥[-12-10]Sap. This is equivalent to a 30° rotation in the basal (0001) plane. The film is found to contain a high density of stacking faults with average spacing 15 nm terminated by partial dislocations. The density of partial dislocations was estimated from plan-view TEM image to be 7×109 cm−2. The cross-section image of GaN film shows the density of stacking faults is highest in the vicinity of the interface and decreases markedly near the top of the layer. Inverted domain boundaries, which are almost perpendicular to the film surface, are also visible. The concentration of threading dislocation is relatively low (∼;2×108 cm−2), compared to misfit dislocations. The average distance between misfit dislocations was found to be 22 Å. Contrast modulations due to the strain near misfit dislocations are seen in high-resolution cross-sectional TCM micrograph of GaN/α-Al2O3 interface. This interface is sharp and does not contain any transitional layer. The interfacial region has a high density of Shockley and Frank partial dislocations. Mechanism of accommodation of tensile, sequence and tilt disorder through partial dislocation generation is discussed. In order to achieve low concentration of threading dislocations we need to establish favorable conditions for some stacking disorder in thin layers above the film-substrate interface region.


2011 ◽  
Vol 679-680 ◽  
pp. 512-515 ◽  
Author(s):  
Maelig Ollivier ◽  
Arnaud Mantoux ◽  
Edwige Bano ◽  
Konstantinos Rogdakis ◽  
Konstantinos Zekentes ◽  
...  

Silicon microwires (MWs) previously synthesized using the VLS method with gold catalyst are being carburized at 1100°C under methane aiming to their conversion to SiC. SEM, TEM as well as XPS and Raman spectroscopy were used for structural and morphological characterization. After carburization achievement, SiC is found to be polycrystalline with a high density of stacking faults associated to an increase of surface roughness. Directions for the carburization process optimization are given.


2011 ◽  
Vol 99 (15) ◽  
pp. 153108 ◽  
Author(s):  
Ting-Hang Pei ◽  
Subramani Thiyagu ◽  
Zingway Pei

Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5563
Author(s):  
Zhe Wu ◽  
Yang Zhang ◽  
Haifeng Jiang ◽  
Shuai Zhao ◽  
Qingnan Wang

Wf/Cu82Al10Fe4Ni4 composites were fabricated by the pressure infiltration method. The composites were compressed by means of a split Hopkinson pressure bar (SHPB) with strain rates of 800 and 1600 s−1 at different temperatures. The microstructure of the composites after dynamic compressing was analyzed by transmission electron microscopy (TEM). Observation revealed that there were high-density dislocations, stacking faults, twins, and recrystallization existing in the copper alloy matrix of the composites. High-density dislocations, stacking faults, and twins were generated due to the significant plastic deformation of the copper alloy matrix under dynamic load impact. We also found that the precipitated phase of the matrix played a role in the second phase strengthening; recrystallized microstructures of copper alloy were generated due to dynamic recrystallization of the copper alloy matrix under dynamic compression at high temperatures.


ACS Omega ◽  
2021 ◽  
Author(s):  
Weixi Wang ◽  
Éric Ngo ◽  
Ileana Florea ◽  
Martin Foldyna ◽  
Pere Roca i Cabarrocas ◽  
...  

Nanomaterials ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 966
Author(s):  
Antonio Alessio Leonardi ◽  
Maria José Lo Faro ◽  
Alessia Irrera

Silicon nanowires (Si NWs) are emerging as an innovative building block in several fields, such as microelectronics, energetics, photonics, and sensing. The interest in Si NWs is related to the high surface to volume ratio and the simpler coupling with the industrial flat architecture. In particular, Si NWs emerge as a very promising material to couple the light to silicon. However, with the standard synthesis methods, the realization of quantum-confined Si NWs is very complex and often requires expensive equipment. Metal-Assisted Chemical Etching (MACE) is gaining more and more attention as a novel approach able to guarantee high-quality Si NWs and high density with a cost-effective approach. Our group has recently modified the traditional MACE approach through the use of thin metal films, obtaining a strong control on the optical and structural properties of the Si NWs as a function of the etching process. This method is Complementary Metal-Oxide-Semiconductors (CMOS)-technology compatible, low-cost, and permits us to obtain a high density, and room temperature light-emitting Si NWs due to the quantum confinement effect. A strong control on the Si NWs characteristics may pave the way to a real industrial transfer of this fabrication methodology for both microelectronics and optoelectronics applications.


1993 ◽  
Vol 317 ◽  
Author(s):  
B. Gilles ◽  
A. Marty ◽  
G. Patrat ◽  
J.L. Vassent ◽  
J.C. Joud ◽  
...  

ABSTRACTThe growth of Ni on Au (100) has been investigated by MBE. It has been found that a Metastable BCT Ni (100) phase is coherent with the substrate up to a thickness of 5 ML. Then a structural transformation analogous to a raartensitic transition occurs, and the structure becomes FCC Ni (110). We show that the interfacial stress is progressively relieved by a high density of stacking faults, as was predicted by Bruinsma and Zangwill for epitaxial overlayers with a large Misfit.


2022 ◽  
Vol 211 ◽  
pp. 114496
Author(s):  
Yanmeng Chen ◽  
Tao Guo ◽  
Xiaolu Pang ◽  
Lijie Qiao

Langmuir ◽  
2014 ◽  
Vol 30 (8) ◽  
pp. 2259-2265 ◽  
Author(s):  
Dayong Teng ◽  
Luo Wu ◽  
Weiwei He ◽  
Changhui Ye

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