Contactless electroreflectance studies of surface potential barrier for N- and Ga-face epilayers grown by molecular beam epitaxy

2013 ◽  
Vol 103 (5) ◽  
pp. 052107 ◽  
Author(s):  
R. Kudrawiec ◽  
L. Janicki ◽  
M. Gladysiewicz ◽  
J. Misiewicz ◽  
G. Cywinski ◽  
...  
Keyword(s):  
Molecular Beam Epitaxy ◽  
Potential Barrier ◽  
Surface Potential ◽  
Molecular Beam

Photoreflectance Study of Strained InAIAs/InP Structures

1995 ◽  
Vol 379 ◽  
Author(s):  
Jenn-Shyong Hwang ◽  
W. Y. Chou ◽  
S. L. Tyan ◽  
Y. C. Wang ◽  
J. H. Tung
Keyword(s):  
Molecular Beam Epitaxy ◽  
Electric Field ◽  
Fermi Level ◽  
Layer Thickness ◽  
Surface Potential ◽  
Molecular Beam ◽  
Surface States ◽  
Energy Band Gap ◽  
Characteristic Region ◽  
Surface Fermi Level

ABSTRACTWe have studied the photoreflectance spectra at 300 K from a series of strained In1−xAlxAs/InP (0.42<x<0.57) strained structures grown by molecular beam epitaxy. From the observed Franz-Keldysh Oscillation we evaluate the built-in de electric field and hence the surface potential under different strain. We found that the surface Fermi level is not pinned at midgap under different strainwhich results in contrast to AIGaAs and GaAs. In addition, from the observed dependence of the built-in electric field Fdc and surface potential barrier Vm on the top layer thickness, we conclude that the surface states are distributed over two separate regions within the energy band gap under different strain and the densities of the surface states are as low as (2,71α0.05)x 1011 cm−2 for the distribution near the conduction band and (4.29α0.05)x1011 cm-2 for the distribution near the valence band. The Fermi level is weakly pinned while the top layer thickness is within the characteristic region of each sample.

Potential barrier formed at n-ZnSe regrowth homointerface by molecular beam epitaxy

1999 ◽  
Vol 201-202 ◽  
pp. 623-626 ◽  
Author(s):  
Yuji Yamagata ◽  
Takayuki Sawada ◽  
Kazuaki Imai ◽  
Kazuhiko Suzuki
Keyword(s):  
Molecular Beam Epitaxy ◽  
Potential Barrier ◽  
Molecular Beam

Defects in Heavily-Doped MBE GaAs

1982 ◽  
Vol 40 ◽  
pp. 442-445
Author(s):  
C.B. Carter ◽  
D.M. DeSimone ◽  
T. Griem ◽  
C.E.C. Wood
Keyword(s):  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Heavily Doped

Molecular-beam epitaxy (MBE) is potentially an extremely valuable tool for growing III-V compounds. The value of the technique results partly from the ease with which controlled layers of precisely determined composition can be grown, and partly from the ability that it provides for growing accurately doped layers.

An in situ and ex situ TEM study of the formation of thin cobalt silicide films by molecular beam epitaxy on the silicon (100) surface

1988 ◽  
Vol 46 ◽  
pp. 884-885
Author(s):  
D. Loretto ◽  
J. M. Gibson ◽  
S. M. Yalisove ◽  
R. T. Tung
Keyword(s):  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Defect Density ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Ex Situ ◽  
Metal Base ◽  
In Situ Experiments ◽  
Potential Applications

The cobalt disilicide/silicon system has potential applications as a metal-base and as a permeable-base transistor. Although thin, low defect density, films of CoSi2 on Si(111) have been successfully grown, there are reasons to believe that Si(100)/CoSi2 may be better suited to the transmission of electrons at the silicon/silicide interface than Si(111)/CoSi2. A TEM study of the formation of CoSi2 on Si(100) is therefore being conducted. We have previously reported TEM observations on Si(111)/CoSi2 grown both in situ, in an ultra high vacuum (UHV) TEM and ex situ, in a conventional Molecular Beam Epitaxy system.The procedures used for the MBE growth have been described elsewhere. In situ experiments were performed in a JEOL 200CX electron microscope, extensively modified to give a vacuum of better than 10-9 T in the specimen region and the capacity to do in situ sample heating and deposition. Cobalt was deposited onto clean Si(100) samples by thermal evaporation from cobalt-coated Ta filaments.

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.

The relaxation of compressive biaxial strains in SOS via microtwins

1989 ◽  
Vol 47 ◽  
pp. 608-609
Author(s):  
M. E. Twigg ◽  
E. D. Richmond ◽  
J. G. Pellegrino
Keyword(s):  
Thin Film ◽  
Chemical Vapor Deposition ◽  
Molecular Beam Epitaxy ◽  
Compressive Stress ◽  
Vapor Deposition ◽  
Partial Dislocation ◽  
Molecular Beam ◽  
Volume Fraction ◽  
Chemical Vapor ◽  
Silicon Thin Film

For heteroepitaxial systems, such as silicon on sapphire (SOS), microtwins occur in significant numbers and are thought to contribute to strain relief in the silicon thin film. The size of this contribution can be assessed from TEM measurements, of the differential volume fraction of microtwins, dV/dν (the derivative of the microtwin volume V with respect to the film volume ν), for SOS grown by both chemical vapor deposition (CVD) and molecular beam epitaxy (MBE).In a (001) silicon thin film subjected to compressive stress along the [100] axis , this stress can be relieved by four twinning systems: a/6[211]/( lll), a/6(21l]/(l1l), a/6[21l] /( l1l), and a/6(2ll)/(1ll).3 For the a/6[211]/(1ll) system, the glide of a single a/6[2ll] twinning partial dislocation draws the two halves of the crystal, separated by the microtwin, closer together by a/3.

Sign in / Sign up

Export Citation Format

Share Document