Comparative Study of Interface Structure in GaAs/AlAs Superlattices By Tem and Raman Scattering

1987 ◽  
Vol 102 ◽  
Author(s):  
T. Nakamura ◽  
M. Ikeda ◽  
S. Muto ◽  
S. Komiya ◽  
I. Umebu
Keyword(s):  
Raman Scattering ◽  
Interface Structure ◽  
Atomic Step ◽  
Transition Layers ◽  
Bright Spots ◽  
Transmission Electron ◽  
Scattering Measurements ◽  
Step Density ◽  
Raman Characterization ◽  
Growth Temperature Dependence

ABSTRACTTransition layers in GaAs/AlAs superlattices were studied by high resolution transmission electron microscopy (HRTEM) observations and Raman scattering measurements. We clarified that arrays of bright spots at the interface in the TEM image is a good indicator of the interfacial configuration and that a high atomic step density with intervals of less than 10 nm is necessary for Raman characterization using confined LO phonons.We characterized the growth temperature dependence of the transition layers at the GaAs/AlAs interfaces. For a sample grown at 500'C, the extent of the transition layers is about one monolayer and that of the interfacial step intervals is more than 10 nm. For a sample grown at 700 0 C, these values are about two monolayers and less than 3 nm, respectively.

High Resolution Electron Microscopy Observations About The Interface Structure In A Ti/TiN Multilayer Material

1991 ◽  
Vol 238 ◽  
Author(s):  
X. G. Ning ◽  
L. P. Guo ◽  
R. F. Huang ◽  
J. Gong ◽  
B. H. Yu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Orientation Relationship ◽  
High Resolution Electron Microscopy ◽  
Interface Structure ◽  
Multilayer Material ◽  
Transition Layers ◽  
Transmission Electron ◽  
Resolution Electron ◽  
Specific Orientation

ABSTRACTThe interface structure in a Ti/TiN multilayer material has been investigated by high resolution transmission electron microscopy (HRTEM). It was shown that the α-Ti and β-TiN layers consisted of many cylindrical crystals growing along the close packed directions normal to the surface of a stainless steel. There existed specific orientation relationship at the Ti/TiN interfaces without transition layers: (111)TiN ‖ (001)Ti, [110]TiN ‖ [100]Ti. However there was no such orientation relationship at the Ti/TiN interfaces with TixN (x >1) transition layers.

Raman scattering measurements of vibrational and rotational distributions in expanding nitrogen

1993 ◽  
Author(s):  
WALTER GILLESPIE ◽  
DANIEL BERSHADER ◽  
SURENDRA SHARMA ◽  
STEPHEN RUFFIN
Keyword(s):  
Raman Scattering ◽  
Scattering Measurements

X-Ray and Raman Studies of Interlayer Mixing in SimGem Superlattices

1991 ◽  
Vol 220 ◽  
Author(s):  
R. C. Bowman ◽  
P. M. Adams ◽  
S. J. Chang ◽  
V. Arbet-Engels ◽  
K. L. Wang
Keyword(s):  
Activation Energy ◽  
Raman Scattering ◽  
Vacancy Mechanism ◽  
Strained Si ◽  
X Ray ◽  
Scattering Measurements ◽  
Intensity Changes ◽  
Interface Mixing ◽  
Interdiffusion Coefficients

ABSTRACTInterface mixing between the Ge and Si layers in symmetrically strained SimGem superlattices occurs during post growth thermal anneals. Interdiffusion coefficients were obtained from intensity changes in the low angle superlattice x-ray satellites on samples with nominal periodicities between 1.4nm and 5.6nm. A common activation energy of 3.0±0.1 eV was found. The bulk interdiffusion coefficients for SimGem were derived since measurements were made on samples with different layer thicknesses. Intermixing appears to occur by diffusion of Si atoms into the Ge layers via a vacancy mechanism. Raman scattering measurements support this process as well as the formation of Si1−xGex, alloy layers during the anneals.

Sign in / Sign up

Export Citation Format

Share Document