Asymmetric Relaxation in Epitaxial Layers of III-V Compounds

1990 ◽  
Vol 202 ◽  
Author(s):  
A. G. Turnbull ◽  
G. S. Green ◽  
B. K. Tanner ◽  
M. A. G. Halliwell

ABSTRACTRelaxation in a 3μm epitaxial layer of GaAsSb on GaAs, a 1μm layer of InGaAs on InP and an InGaAs superlattice on InP has been investigated by double crystal X-ray diffractometry and double crystal X-ray synchrotron topography and found to be asymmetric. The origins of assymetric relaxation are discussed and the sensitivity of diffractometry and topography to the detection of layer relaxation compared.

1990 ◽  
Vol 216 ◽  
Author(s):  
H. Uekita ◽  
N. Kitamura ◽  
M. Ichimura ◽  
A. Usami ◽  
T. Wada

ABSTRACTGaSb, AlxGa1-xSb, and AlxGa1-xSb epitaxial layers were grown by the liquid-phase epitaxy and characterized by photoluminescence, Raman spectroscopy, and double-crystal X-ray diffraction. The concentration of residual acceptors which are related to structural defects decreased with lowering growth temperature, but the GaSb epitaxial layer grown at an extremely low temperature of 270°C had poor crystalline quality. The AlxGa1-xSb (x≥0.15) and AlxGa1-xSb (x=0.02) epitaxial layers grown at 270 °C, however, had much better quality than the GaSb epitaxial layer grown at the same temperature.


1992 ◽  
Vol 36 ◽  
pp. 221-229
Author(s):  
D.A. Macquistan ◽  
I.C. Bassignana ◽  
A.J. SpringThorpe ◽  
R. Packwood ◽  
V. Moore

AbstractDouble Crystal X-Ray Diffraction (DCD) is often used to determine the Al content of AlxGa1-xAs/GaAs epitaxial layers. Assessing composition from a measurement of mismatch is problematic because it invokes a number of assumptions. This study bypasses these difficulties by comparing the measurement of mismatch directly with Al composition measurements made by electronprobe microanalysis. A study of coherent epitaxial AlxGa1-xAs layers showed that mismatch varies linearly with composition. The equation Al (x) = |ΔΘ| / 368 summarizes the relationship over the coherent range, where |ΔΘ| is measured in arc seconds.


1991 ◽  
Vol 220 ◽  
Author(s):  
A. R. Powell ◽  
R. A. Kubiak ◽  
T. E. Whall ◽  
E. H. C. Parker ◽  
D. K. Bowen

ABSTRACTWe demonstrate the growth, by MBE, of high sheet density B delta layers in both Si and SiGe epitaxial layers. Double Crystal X-Ray Diffraction is shown to be a non-destructive method of characterising the width of very narrow (0.3 nm) delta layers and the sheet density of the activated B. The ability of delta layers to withstand high temperature anneals is considered and it is found that a 750 °C anneal for 1 hour broadens the delta layer to beyond the width required for carrier confinement.


1989 ◽  
Vol 161 ◽  
Author(s):  
X.L. Zheng ◽  
C.A. Huber ◽  
P. Becla ◽  
M. Shih ◽  
D. Heiman

ABSTRACTEpitaxial layers of Cd1−xMnxTe have been grown on CdTe (100) substrates by evaporating a target with a 1.06 µm pulsed laser. The high - quality materials were characterized by photoluminescence spectroscopy (PL) and energy dispersive analysis of x-ray (EDAX). We find that the incorporation of the Mn in the epitaxial layer is about two - thirds of the concentration in the target. A comparison is made to the epitaxial layers grown on CdTe (111) and GaAs (100) substrates.


1990 ◽  
Vol 208 ◽  
Author(s):  
R. N. Sacks

ABSTRACTSome of today's most promising and interesting semiconductor devices use only a few thin epitaxial layers of III-V materials, where each layer may be only 100 to 1,000A thick. There is a need for fast, accurate, non-destructive analysis techniques for these structures. Double-crystal x-ray diffraction has proven to be an excellent method for measuring composition, thickness, interface sharpness, and overall crystalline quality of III-V heterostructures. Data is presented on the use of a Bede QC1 automated table-top double-crystal diffractometer for the analysis of (AI,Ga)As, (ln,Ga)As, and GaAs epitaxial layers grown by Molecular Beam Epitaxy (MBE). It is shown that this technique can directly detect and analyze single layers of (In,Ga)As as thin as 200A, and in some cases, can indirectly detect layers of GaAs or (AI,Ga)As as thin as 100A without unusual measures such as glancing angle diffraction. The rocking curve results are compared with values predicted by RHEED intensity oscillation measurements, and with computer simulations using a commercial software package.


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