Surface segregation during Si/Gen/Si(100) interface formation

1994 ◽  
Vol 76 (6) ◽  
pp. 3911-3913 ◽  
Author(s):  
Z. H. Lu ◽  
J.‐M. Baribeau ◽  
D. J. Lockwood
Keyword(s):  
Surface Segregation ◽  
Interface Formation

Role of Ge surface segregation in Si/Ge interfacial ordering: Interface formation on a monohydride surface

1995 ◽  
Vol 51 (20) ◽  
pp. 14786-14789 ◽  
Author(s):  
Nobuyuki Ikarashi ◽  
Atsushi Oshiyama ◽  
Akira Sakai ◽  
Toru Tatsumi
Keyword(s):  
Surface Segregation ◽  
Interface Formation

Growth of Group IV-IV Heterostructures: Initial Stages of Interface Formation

1986 ◽  
Vol 67 ◽  
Author(s):  
H.-J. Gossmann ◽  
L. C. Feldman
Keyword(s):  
Surface Segregation ◽  
Substrate Surface ◽  
Group Iv ◽  
Necessary Condition ◽  
Ion Scattering ◽  
Interface Formation ◽  
General Role ◽  
Low Energy Electron ◽  
Critical Coverage

ABSTRACTThe two major issues in the growth of a heterostructure are (1) the degree of perfection of the overlayer and (2) the sharpness of the interface. The initial stages of interface formation play a crucial role in this respect. Relevant questions are addressed under atomically clean conditions in the Si/Ge Si/Si and Ge/Sn systems, using ion scattering surface analysis, low energy electron diffraction and Auger electron spectroscopy. Of particular interest with respect to (1) is the general role of reconstruction in epitaxial growth: A necessary condition for perfect growth is the reordering of the substrate surface reconstruction. We show that the deposition temperature necessary to achieve this reordering depends strongly on the topography of the substrate reconstruction. For example, Ge deposition at room-temperature reorders the Si(100)2×1 reconstruction but not the Si(111)7×7, implying different epitaxial temperatures for these two substrates. To illustrate (2) we discuss the complex growth and anomalous diffusion found in the Ge/Sn system. Below a certain critical coverage Θc (1.15·1015 cm−2) no indiffusion of the Sn overlayer takes place, even at 700 K, although above Θc severe indiffusion does occur at this temperature. This result is discussed in terms of theories of surface segregation.

Near-Surface Aggregation of Sn In Heavily Sn-Doped GaAs Films Grown By Molecular Beam Epitaxy

1985 ◽  
Vol 43 ◽  
pp. 368-369
Author(s):  
S. H. Chen
Keyword(s):  
Molecular Beam Epitaxy ◽  
Cross Section ◽  
Electron Spectroscopy ◽  
Molecular Beam ◽  
Surface Segregation ◽  
Secondary Ion Mass Spectrometry ◽  
Specimen Preparation ◽  
Near Surface ◽  
Gaas Films ◽  
Secondary Ion

Sn has been used extensively as an n-type dopant in GaAs grown by molecular-beam epitaxy (MBE). The surface accumulation of Sn during the growth of Sn-doped GaAs has been observed by several investigators. It is still not clear whether the accumulation of Sn is a kinetically hindered process, as proposed first by Wood and Joyce, or surface segregation due to thermodynamic factors. The proposed donor-incorporation mechanisms were based on experimental results from such techniques as secondary ion mass spectrometry, Auger electron spectroscopy, and C-V measurements. In the present study, electron microscopy was used in combination with cross-section specimen preparation. The information on the morphology and microstructure of the surface accumulation can be obtained in a fine scale and may confirm several suggestions from indirect experimental evidence in the previous studies.

A New Numerical Model for Electron-Probe Analysis at High Depth Resolution

1996 ◽  
Vol 54 ◽  
pp. 490-491
Author(s):  
P.-F. Staub ◽  
C. Bonnelle ◽  
F. Vergand ◽  
P. Jonnard
Keyword(s):  
Electron Probe ◽  
Surface Segregation ◽  
Depth Distribution ◽  
Computing Time ◽  
Depth Resolution ◽  
Physical Parameters ◽  
Electron Probe Analysis ◽  
Interface Phases ◽  
Excitation Conditions ◽  
High Depth

Characterizing dimensionally and chemically nanometric structures such as surface segregation or interface phases can be performed efficiently using electron probe (EP) techniques at very low excitation conditions, i.e. using small incident energies (0.5<E0<5 keV) and low incident overvoltages (1<U0<1.7). In such extreme conditions, classical analytical EP models are generally pushed to their validity limits in terms of accuracy and physical consistency, and Monte-Carlo simulations are not convenient solutions as routine tools, because of their cost in computing time. In this context, we have developed an intermediate procedure, called IntriX, in which the ionization depth distributions Φ(ρz) are numerically reconstructed by integration of basic macroscopic physical parameters describing the electron beam/matter interaction, all of them being available under pre-established analytical forms. IntriX’s procedure consists in dividing the ionization depth distribution into three separate contributions:

Surface segregation in model symmetric polyolefin diblock copolymer melts

1994 ◽  
Vol 4 (12) ◽  
pp. 2231-2248 ◽  
Author(s):  
Mohan Sikka ◽  
Navjot Singh ◽  
Frank S. Bates ◽  
Alamgir Karim ◽  
Sushil Satija ◽  
...  
Keyword(s):  
Diblock Copolymer ◽  
Surface Segregation ◽  
Copolymer Melts

XPS study of the chemisorption induced surface segregation in LaNi5 and ThNi5

1981 ◽  
Vol 42 (7) ◽  
pp. 1025-1028 ◽  
Author(s):  
L. Schlapbach ◽  
C.R. Brundle
Keyword(s):  
Surface Segregation ◽  
Xps Study

Is it a Right Assumption That B and Ge are Distributed Randomly After Growing a Strained HBT-Structure?

2002 ◽  
Vol 716 ◽  
Author(s):  
Victor I. Kol'dyaev
Keyword(s):  
Surface Segregation ◽  
Initial Conditions ◽  
Initial Condition ◽  
Basic Assumptions ◽  
Transient Diffusion ◽  
Segregation Process ◽  
Main Observation

AbstractIt is accepted that surface Ge atoms are considered to be responsible for the surface B segregation process. A set of original experiments is carried out. A main observation from the B and Ge profiles grown at different conditions shows that at certain conditions B is taking initiative and determine the Ge surface segregation process. basic assumptions are suggested to self-consistently explain these original experimental features and what is observed in the literature. These results have a strong implication for modeling the B diffusion in Si1-xGex where the initial conditions should be formulated accounting for the correlation in B and Ge distribution. A new assumption for the initial condition to be “all B atoms are captured by Ge” is regarded as a right one implicating that there is no any transient diffusion representing the B capturing kinetics.

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