Epitaxial Growth OF (001)- and (111)-Oriented PTMNSB Films and Multilayers

1995 ◽  
Vol 384 ◽  
Author(s):  
M.C. Kautzky ◽  
B.M. Clemens

ABSTRACTIn this paper we report the successful growth of single-phase epitaxial PtMnSb films and multilayers by dc magnetron cosputtering, both in the (001) orientation on MgO(001) and W(001), and in the (111) orientation on Al2O3 (0001). Single-layer films in the thickness range 50Å≤t≤1000Å were grown and characterized using x-ray diffraction (XRD), magneto-optic Kerr effect (MOKE), and vibrating sample magnetometry (VSM). The in-plane orientation relationships, as determined by asymmetric XRD, were PtMnSb[100]∥MgO[110], PtMnSb[100]∥W[100], and PtMnSb[101∥Al2O3[2110]. The crystalline quality of the films was found to depend strongly upon the substrate, growth temperature, film thickness, and presence of a capping layer, but rocking curve widths of 1° or less were achieved on each substrate. Measurement of the in-plane strain showed that the films were almost entirely relaxed, with strains <1%. In-plane magnetization was observed in all cases, with moments and coercivities in the 400-500 emu/cm3 and 100-200 Oe ranges respectively. Polar Kerr spectra showed large rotations (0.75° - 1.03°), whose peak wavelengths appear to depend on both film structure and optical interference effects.

1999 ◽  
Vol 4 (S1) ◽  
pp. 429-434 ◽  
Author(s):  
C. H. Wei ◽  
Z. Y. Xie ◽  
J. H. Edgar ◽  
K. C. Zeng ◽  
J. Y. Lin ◽  
...  

Boron was incorporated into GaN in order to determine its limits of solubility, its ability of reducing the lattice constant mismatch with 6H-SiC, as well as its effects on the structural and optical properties of GaN epilayers. BxGa1−xN films were deposited on 6H-SiC (0001) substrates at 950 °C by low pressure MOVPE using diborane, trimethylgallium, and ammonia as precursors. A single phase alloy with x=0.015 was successfully produced at a gas reactant B/Ga ratio of 0.005. Phase separation into pure GaN and BxGa1−xN alloy with x=0.30 was deposited for a B/Ga reactant ratio of 0.01. This is the highest B fraction of the wurtzite structure alloy ever reported. For B/Ga ratio ≥ 0.02, no BxGa1−xN was formed, and the solid solution contained two phases: wurtzite GaN and BN based on the results of Auger and x-ray diffraction. The band edge emission of BxGa1−xN varied from 3.451 eV for x=0 with FWHM of 39.2 meV to 3.465 eV for x=0.015 with FWHM of 35.1 meV. The narrower FWHM indicated that the quality of GaN epilayer was improved with small amount of boron incorporation.


1998 ◽  
Vol 537 ◽  
Author(s):  
C. H. Wei ◽  
Z. Y. Xie ◽  
J. H. Edgar ◽  
K. C. Zeng ◽  
J. Y. Lin ◽  
...  

AbstractBoron was incorporated into GaN in order to determine its limits of solubility, its ability of reducing the lattice constant mismatch with 6H-SiC, as well as its effects on the structural and optical properties of GaN epilayers. BxGal-xN films were deposited on 6H-SiC (0001) substrates at 950 °C by low pressure MOVPE using diborane, trimethylgallium, and ammonia as precursors. A single phase alloy with x=0.015 was successfully produced at a gas reactant B/Ga ratio of 0.005. Phase separation into pure GaN and BxGal-xN alloy with x=0.30 was deposited for a B/Ga reactant ratio of 0.01. This is the highest B fraction of the wurtzite structure alloy ever reported. For B/Ga ratio ≥ 0.02, no BxGal-xN was formed, and the solid solution contained two phases: wurtzite GaN and BN based on the results of Auger and x-ray diffraction. The band edge emission of BxGal-xN varied from 3.451 eV for x=0 with FWHM of 39.2 meV to 3.465 eV for x=0.015 with FWHM of 35.1 meV. The narrower FWHM indicated that the quality of GaN epilayer was improved with small amount of boron incorporation.


1994 ◽  
Vol 343 ◽  
Author(s):  
J.D. Jarratt ◽  
J.A. Barnard

ABSTRACTGiant Magnetoresistance (GMR), crystal structure, and magnetic properties have been investigated in a series of sputtered Ni66Fe16Co18/Ag multilayer films with induced uniaxial anisotropy. The film thickness ranges studied were 20 and 25 Å for NiFeCo, and 25 to 50 Å for Ag. GMR was only evident in the films after post-deposition annealing. This onset of GMR is thought to be due to the breaking up of the NiFeCo layers into ferromagnetic platelets or islands by the immiscible Ag diffusing perpendicular to the film plane along the grain boundaries. The magnitude and field sensitivity of the GMR was dependent on the annealing time and temperature. High angle x-ray diffraction (HXRD) was used to reveal the overall film structure and growth texture and low angle XRD (LXRD) was used to investigate the quality of the multilayer structures. M-H hysteresis loops revealed in-plane uniaxial anisotropy in as-deposited films which is eventually eliminated with annealing. The easy axis squareness experiences a pronounced decrease with lower temperature annealing, but then increases slightly with annealing temperature.


1986 ◽  
Vol 90 ◽  
Author(s):  
I. B. Bhat ◽  
N. R. Taskar ◽  
J. Ayers ◽  
K. Patel ◽  
S. K. Ghandhi

ABSTRACTCadmium telluride layers were grown on InSb substrates by organometallic vapor phase epitaxy and examined using secondary ion mass spectrometry (SIMS), photoluminescence (Pb) and double crystal x-ray diffraction (DCD). The substrate temperature and the nature of the surface prior to growth are shown to be the most important parameters which influence the quality of CdTe layers. Growth on diethyltelluride (DETe) stabilized InSb substrates resulted in CdTe growth with a misorientation of about 4 minutes of arc with respect to the substrates. On the other hand, the grown layers followed the orientation of the substrates when a dimethylcadmium (DMCd) stabilized InSb was used. Growth at 350°C resulted in the smallest x-ray rocking curve (DCRC) full width at half maximum (FWHM) of about 20 arc seconds.


2006 ◽  
Vol 46 ◽  
pp. 146-151
Author(s):  
Andriy Lotnyk ◽  
Stephan Senz ◽  
Dietrich Hesse

Single phase TiO2 thin films of anatase structure have been prepared by reactive electron beam evaporation. Epitaxial (012)- and (001)-oriented anatase films were successfully obtained on (110)- and (100)-oriented SrTiO3 substrates, respectively. X-ray diffraction and cross section transmission electron microscopy investigations revealed a good epitaxial quality of the anatase films grown on the SrTiO3 substrates.


2001 ◽  
Vol 16 (9) ◽  
pp. 2463-2466 ◽  
Author(s):  
Yong Kwan Kim ◽  
Kyeong Seok Lee ◽  
Sunggi Baik

Epitaxial (Pb1−xSrx)TiO3 (PST, x = 4 0.0–0.24) thin films were grown on MgO(001) single-crystal substrates by pulsed laser deposition. General x-ray diffraction techniques including θ–2θ scan and rocking curve were used to determine lattice constants, degree of c-axis orientation, and crystal quality of the tetragonal thin films. The degree of c-axis orientation in the epitaxial PST films increased as Sr concentration (x) increased, which in turn induces the systematic change in the Curie temperature as well as the transformation strain at and below the Curie temperature. An inverse relation between the c-domain abundances and the transformation strains is established.


1997 ◽  
Vol 475 ◽  
Author(s):  
J.F. Bobo ◽  
K. Bessho ◽  
F.B. Mancoff ◽  
P.R. Johnson ◽  
M.C. Kautzky ◽  
...  

ABSTRACTWe have grown superlattices based on the Clb Heusler alloys PtMnSb, CuMnSb and NiMnSb between 200–500°C on A12O3 (0001). X-ray diffraction (XRD) indicates (111) oriented ordered structures for growth at 300°C. Higher deposition temperature leads to interdiffusion, loss of the multilayer structure and appearance of extra phases. Growth at 200°C slightly reduces the intermixing but also reduces the quality of the crystal structure. For PtMnSb/CuMnSb, we found an enhancement of the saturation magnetization compared to equivalent PtMnSb single layer films and a CuMnSb spacer thickness dependence of the squareness of the M(H) 100ps suggestive of interlayer coupling. Short periodicity NiMnSb/PtMnSb superlattices show an in-plane magnetic easy axis, but correction for shape anisotropy indicates a tendency for perpendicular anisotropy.


1987 ◽  
Vol 91 ◽  
Author(s):  
J.W. Lee ◽  
D.K. Bowen ◽  
J.P. Salerno

ABSTRACTIn an effort to evaluate the near surface crystal quality of GaAs on Si wafers, {224} plane diffraction were investigated using a conventional double crystal x-ray diffractometer without any high intensity radiation source. The x-ray incident angle to wafer surface varied from 3.6 to 9.6 degrees for different {224} planes due to the substrate tilt angle of 3 degrees. The GaAs to Si rocking curve intensity ratio increased significantly as the incident angle decreased. For the diffraction with 3.6 degree incident angle, only the GaAs peak was detected from the 3.5 um thick GaAs on Si wafer and the GaAs peak became narrower. These indicates that this conventional x-ray diffraction technique is applicable for the near surface quality evaluation of GaAs on Si wafers.


2012 ◽  
Vol 190 ◽  
pp. 109-112
Author(s):  
Y.A. Danilov ◽  
B.N. Zvonkov ◽  
Alexei V. Kudrin ◽  
O.V. Vikhrova ◽  
S.M. Plankina ◽  
...  

t is reported about fabrication by laser deposition in a gaseous environment of epitaxial layers of ferromagnetic semiconductors GaMnSb and InMnSb. Investigations of x-ray diffraction and Raman scattering showed reasonably good crystal quality of GaMnSb and InMnSb layers. Magnetic properties were investigated by magneto-optical transversal Kerr effect and Hall effect. It is established, that GaMnSb layers are ferromagnetic at room temperature. In contrast, InMnSb samples demonstrate the ferromagnetic properties only at low temperatures (< 70 K).


1992 ◽  
Vol 275 ◽  
Author(s):  
Koichi Mizuno ◽  
Yo Ichikawa ◽  
Kentaro Setsune

ABSTRACTCrystalline quality of Bi-based oxide films has been evaluated by means of X-ray diffraction (XRD) and ion-channeling on the Rutherford backscattering (RBS). The films were sputter deposited 2201-phase Bi2Sr2Cu1O8-δ (BSCO) and 2212-phase Bi2Sr2Ca1Cu2O8-δ (BSCCO). They were prepared on MgO(100) and SrTiO3(100) substrates at the low temperature of 650°C during the deposition. The best quality, however thin films had poor crystallinity compared to single crystals, was obtained with the 2201-phase BSCO film that was deposited on a SrTiO3(100) substrate. The full width at half maximum (FWHM) value of the rocking curve on XRD for the film was estimated as 1560 (arc sec).


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