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Facet formation and selective area epitaxy of InGaAs by chemical beam epitaxy using unprecracked monoethylarsine
Published in Jong-Chun Woo, Yoon Soo Park, Compound Semiconductors 1995, 2020
Sung-Bock Kim, Seong-Ju Park, Jeong-Rae Ro, El-Hang Lee
There have been several approaches to achieve lateral confinements using physical and chemical processing. Electron or ion beam lithography followed by dry etching(Kash et al 1989; Miller et al 1989), ion beam implantation for impurity-induced disordering(Cibert et al 1986), or selective diffusion(Zarem et al 1989) has been used to define these nanostructures. However, such techniques produce serious interface damages during the etching process or implantation. These damages are known to seriously reduce quantum efficiency. Thus, the selective area epitaxy without air-exposed and etching damaged interfaces is highly desirable. The control of facet formation using selective area epitaxy has been considered as one of the key issues for fabricating such quantum-confined structures with damage-free interfaces.
Mismatched Heteroepitaxial Growth and Strain Relaxation
Published in John E. Ayers, Heteroepitaxy of Semiconductors, 2018
However, it was assumed that the first-order reaction was due to the loss of threading dislocations to sidewalls in the case of selective area epitaxy. The first-order constant was calculated from C1 = G / λ, where λ is a length characterizing the travel necessary to reach a mesa sidewall and G is a geometric factor associated with the inclination of threading dislocations and G ≈ 1. The second-order constant was calculated from C2 = 2Gr1, where r1 is a characteristic length for the second-order reaction. Romanov et al. wrote the solution in the form () D=D0(1+C2D0/C1)exp[C1(h−h0)]−D0C2/C1
Low-Dimensional Systems
Published in Ferdinand Scholz, Compound Semiconductors, 2017
Another similar approach starts with masking a semiconductor surface with a dielectric mask (e.g., SiO2) containing some small openings (again produced by conventional optical lithography). In a subsequent epitaxial process, the growth only starts in these openings: Stripes or pyramids are formed by selective area epitaxy. Their shape depends on the details of the growth conditions. Again very sharp tips can be realized. When depositing eventually another material, surface migration may lead to a quantum wire or quantum dot like structure at the tip of the stripe or pyramid (see Fig. 10.3, right). However, this process was not yet so successful, as the control of the quantum wire or quantum dot shape depends critically on the timing of the growth process.Bottom-up approach: Self-assembled quantum dots
Nanowire Transistors: A Next Step for the Low-Power Digital Technology
Published in IETE Journal of Research, 2021
D. Ajitha, K. N. V. S. Vijaya Lakshmi, K. Bhagya Lakshmi
Over the last decade, several direct deposition methods for nanowire fabrication that do not require metal nanoparticles have been found making them appealing for a variety of applications. Selective-Area Epitaxy (SAE) Method [36], Seed-Induced Nanowire Growth [37] and Screw-Dislocation-Driven Nanowire Growth [38] are the commonly used methods. In general, preparing ultrathin nanowires with consistent diameters of less than 5 nm is difficult. Several research groups have reported the synthesis of ultrathin AuCl complexes [39], Au nanowires [40] and ultrathin nano-crystals [41].