Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Silicon (011) and Silicon Germanium (011) Gas-Source Molecular Beam Epitaxy: Surface Reconstructions, Growth Kinetics, and Germanium Segregation
Author: Morphological Evolution During Molecular Beam Epitaxy of Germanium/germanium(001) and Silicon/germanium(111).
Author: Chemical Abstracts
Author: Growth of Silicon(1-x) Germanium(x) from Disilane and Digermane by Gas-source Molecular Beam Epitaxy
Author: Thomas Richard BramblettPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The growth rate R of Si(001), Ge(001), and $\rm Si\sb{1-x}Ge\sb{x}(001)$ films deposited on Si(001)2 $\times$ 1 substrates from $\rm Si\sb2H\sb6$ and $\rm Ge\sb2H\sb6$ by gas-source molecular-beam epitaxy (GS-MBE) were determined as a function of temperature T$\sb{\rm s}$(300-950$\sp\circ$C) and impingement flux J (0.3-$7.7\times10\sp{16}$ cm$\sp{-2}$ s$\sp{-1}$). R(T$\sb{\rm s}$,J) curves for Si and Ge films were well described using a model, with no fitting parameters, based upon dissociative chemisorption followed by a series of surface decomposition reactions with the rate-limiting step being first-order hydrogen desorption from the surface monohydride. The hydrogen desorption activation energy for Si and Ge surfaces were found to be 2.04 eV and 1.56 eV, respectively. The zero-coverage reactive sticking probability in the impingement-flux-limited growth regime was found to be 0.036 and 0.052 for $\rm Si\sb2H\sb6$ and $\rm Ge\sb2H\sb6,$ respectively. The growth rate of SiGe alloys R$\sb{\rm SiGe}$ as a function of the bulk Ge content x was found to be a complex. In the surface-reaction-limited regime, R$\sb{\rm SiGe}$ increased with Ge surface coverage $\theta\sb{\rm Ge}$ due to the lower activation energy of H$\sb2$ desorption from Ge than from Si. However, in the impingement-flux-limited regime R$\sb{\rm SiGe}$ decreases with $\theta\sb{\rm Ge}$ due to the lower reactive sticking probability of $\rm Si\sb2H\sb6$ on Ge surface sites with respect to on Si sites. The Ge fraction, x1$\sb{\rm Ge}$, of SiGe alloys was determined as a function of growth temperature T$\sb{\rm s}$ and incident flux ratios $\rm J\sb{Ge2H6}/J\sb{Si2H6}.$ The results were explained by a kinetic model accounting for four simultaneous reaction pathways: reaction of $\rm Si\sb2H\sb6$ with Si surface sites, $\rm Si\sb2H\sb6$ with Ge sites, $\rm Ge\sb2H\sb6$ with Si sites, and $\rm Ge\sb2H\sb6$ with Ge sites. The cross-term reactive sticking probabilities, $\rm S\sbsp{Ge2H6}{Si}$ and $\rm S\sbsp{Si2H6}{Ge}$, were estimated to be 0.33 and $5.2\times10\sp{-3}$ respectively.
Proceedings of the Second International Symposium on Silicon Molecular Beam Epitaxy
Author: John Condon BeanPublisher:
ISBN:
Category : Epitaxy
Languages : en
Pages : 682
Book Description
B-incorporation Kinetics and Charge Transport Property of Silicon Germanide(001) Layer Grown by GS-MBE from Silicon Hydride, Germanium Hydride, and Boron Hydride
Author: Qing LuPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The growth rates of Si(001) and Ge(001) by gas-source molecular-beam epitaxy (GS-MBE) from $\rm Si\sb2H\sb6$ and $\rm Ge\sb2H\sb6$ as a function of T$\sb{\rm s}$ are well described by a model based upon dissociative $\rm Si\sb2H\sb6$ and $\rm Ge\sb2H\sb6$ chemisorption followed by a series of surface decomposition reactions with the rate-limiting step being first-order hydrogen desorption from Si and Ge monohydride for which the activation energy is 2.04 and 1.56 eV, respectively. The zero-coverage reactive sticking probability of $\rm Si\sb2H\sb6$ on Si(001)2 x 1 ($\rm Ge\sb2H\sb6$ on Ge(001)2 x 1) in the impingement-flux-limited growth regime was found to be $\rm S\sbsp{Si\sb2H\sb6}{Si} = 0.036\ (S\sbsp{Ge\sb2H\sb6}{Ge} = 0.052).$ The growth rate of $\rm Si\sb{1-x}Ge\sb{x}$ alloys R$\sb{\rm SiGe}$ decreases somewhat with increasing $\rm G\sb2H\sb6$ in the flux-limited growth mode while dramatically increasing $\rm R\sb{SiGe}$ in the surface-reaction-limited regime.
Kinetic Studies of Growth of Silicon and Silicon Germanium Thin Films: Gas-surface Reactivity, Germanium Surface Segregation, and the Effect of Coincident Atomic Hydrogen
Author: Yongjun ZhengPublisher:
ISBN: 9780599831490
Category :
Languages : en
Pages : 275
Book Description
Based on the kinetic studies presented in this thesis, a novel process was proposed to achieve selective epitaxial growth of Si and Si1-x Gex. Preliminary results show that up to 300 nm epitaxial silicon has been grown while with no sign of polycrystalline silicon growth.
Evolution of the Surface Morphology of Homoepitaxial Germanium(001) and Heteropitaxial Silicon(0.5) Germanium(0.5)/germanium(001) Deposited by Molecular Beam Epitaxy at Reduced Temperatures
Author: Joseph Edward Van NostrandPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
We present comprehensive experimental results on the fashion in which the Ge(001) surface roughens as a function of film thickness, deposition temperature, and substrate miscut. The results allow us to write empirical expressions for feature spacing and roughness amplitude of the growing surface over a wide range of film thicknesses and deposition temperatures. We show that layer-by-layer growth on a singular surface in the presence of a small Ehrlich-Schwoebel leads to mound formation, and, from our experimental results, we extract an activation energy for the Ehrlich-Schwoebel barrier of $rm Esb{ES}approx 1meV$ for Ge(001). The effect of the Ehrlich-Schwoebel barrier does not diminish with an increase in deposition temperature, and hence the transition of the growth mode from multilayer to step flow is due to the competing process of smoothing becoming the dominant mechanism. Deposition on a vicinal surface miscut in the (011) results in the formation of elongated mounds bounded by ${105}$ facets. Thin $rm Sisb{0.5}Gesb{0.5}/Ge(001)$ films deposited in the presence of tensile strain result in the formation of Shockley partial misfit dislocations and a subsequent stacking fault. The stacking faults extend to the film surface, where they impede step flow. This results in step bunching and the formation of rectangular mounds on the surface. Annealing these films results in an inversion of the mounds into pits.
Rapid Thermal Vapor Phase Epitaxy
Author: John D. LeightonAmerican Doctoral Dissertations
Author: Publisher:
ISBN:
Category : Dissertation abstracts
Languages : en
Pages : 848
Book Description