Xafs as a Direct Local Structural Probe in Revealing the Effects of C Presence in B Diffusion in Sige Layers

2004 ◽  
Vol 810 ◽  
Author(s):  
M. Alper Sahiner ◽  
Parviz Ansari ◽  
Malcolm S. Carroll ◽  
Charles W. Magee ◽  
Steven W. Novak ◽  
...  
Keyword(s):  
Local Structure ◽  
Direct Evidence ◽  
Structural Information ◽  
Chemical Vapor ◽  
Si Substrates ◽  
Boron Doped ◽  
Structural Probe ◽  
Diffusion Mechanisms ◽  
X Ray Absorption ◽  
Secondary Ion

ABSTRACTThe local structural information around the germanium atom in boron doped SiGe alloys is important in understanding the dopant diffusion mechanisms. Epitaxial SiGe test structures with B and C markers were grown on Si substrates by using rapid thermal chemical vapor deposition (RTCVD). The local structure around the Ge atom was probed using Ge K-edge x-ray absorption fine structure spectroscopy (XAFS) to determine the effects of the B and C on the Ge sites. The concentration profiles obtained from secondary ion mass spectroscopy are correlated with the Ge XAFS results. The modifications on the local structure around the Ge atoms are revealed from the multiple scattering analyses on the Ge near-neighbors. First and second shell XAFS fits to the B doped SiGe samples indicate a direct evidence of the Ge trapping of the B atoms whereas the C is randomly distributed to the Si lattice sites.

Short Range Order Strucrures in Y-Pr-Ba-Cu-O System Studied by X-Ray Absorption Fine Structure (XAFS) Techniques

1990 ◽  
Vol 209 ◽  
Author(s):  
Y.H. Kao ◽  
A. Krol ◽  
Z.H. Ming ◽  
C.S. Lin ◽  
Y.L. Soo ◽  
...  
Keyword(s):  
Fine Structure ◽  
Local Structure ◽  
Short Range ◽  
Direct Evidence ◽  
Nearest Neighbor ◽  
Compound System ◽  
Local Distribution ◽  
X Ray ◽  
Absorption Fine ◽  
X Ray Absorption

ABSTRACTLocal structure around the constituent atoms in the compound system Y1-xPrxBa2CU3O7-y has been investigated by means of x-ray absorption fine structure (XAFS) techniques. By comparing the local structure in the compound x=1 with its counterpart x=0, the XAFS results provide a direct evidence that Pr has replaced Y in the material. The nearest-neighbor structure in the CuO2 planes seems to remain intact as × varies from 0 to 1, indicating that substitution of Pr for Y does not disturb the local distribution of holes in the CuO2 planes. We suggest that local disorder and distortions in the second-neighbor bonding configuration could be responsible for suppression of superconductivity with increasing Pr content in the system.

Investigation of the Dopant Distribution in thin Epitaxial Silicon Layers by Means of Spreading Resistance Probe and Secondary Ion Mass Spectrometry

1997 ◽  
Vol 500 ◽  
Author(s):  
Ilya Karpov ◽  
Catherine Hartford ◽  
Greg Moran ◽  
Subramania Krishnakumar ◽  
Ron Choma ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Secondary Ion Mass Spectrometry ◽  
Chemical Vapor ◽  
Doping Profile ◽  
Epitaxial Silicon ◽  
Spreading Resistance ◽  
Boron Doped ◽  
Ion Mass Spectrometry ◽  
Chemical Profiles ◽  
Secondary Ion

ABSTRACTIn this paper, we examine the dopant distributions in 1.8 to 4 micron-thick boron- and phosphorus-doped epitaxial silicon layers. These layers were grown by chemical vapor deposition (CVD) on arsenic-, antimony-, or boron-doped (100)- and (111)-oriented substrates. We performed doping profile studies by means of local resistivity measurements using a spreading resistance probe (SRP). Chemical profiles of the dopants were also obtained using secondary ion mass spectrometry (SIMS).

Clustering Analysis in Boron and Phosphorus Implanted (100) Germanium by X-Ray Absorption Spectroscopy

2005 ◽  
Vol 864 ◽  
Author(s):  
M. Alper Sahiner ◽  
Parviz Ansari ◽  
Malcolm S. Carroll ◽  
C. A. King ◽  
Y. S. Suh ◽  
...  
Keyword(s):  
Secondary Ion Mass Spectrometry ◽  
Semiconductor Device ◽  
Structural Information ◽  
High Mobility ◽  
New Developments ◽  
X Ray ◽  
Structural Modifications ◽  
Postimplantation Annealing ◽  
X Ray Absorption ◽  
Secondary Ion

AbstractRecently, germanium based semiconductor device technology gained renewed interest due to new developments such as the use of high-k dielectrics for high mobility Ge MOSFETS. However, a systematic local structural investigation of clustering of dopants has been lacking in the literature. In this study, we present a detailed local structural analysis of boron and phosphorus implanted Ge wafers. We have used Ge K-edge x-ray absorption fine-structure spectroscopy (XAFS) in order to probe the local structural modifications around the Ge atom under various implantation parameters and postimplantation annealing treatments. The (100) Ge wafers were implanted and with 11B+ or 31P+ using energies ranging from 20 keV to 320 keV and doses of 5×1013 to 5×1016/cm2. Pieces of the implanted wafers were subjected to thermal annealing at 400°C or 600°C for three hours in high purity nitrogen. Secondary ion mass spectrometry (SIMS) measurements on these wafers were used to correlate the dopant concentration profiles with the local structural information obtained from XAFS. B and P implanted Ge exhibit distinct responses to annealing. For the P implanted Ge samples annealing leads to recrystallization of Ge with increasing annealing temperature, but also an increase in Ge Debye-Waller factors, whereas B implanted Ge samples e×hibit recrystallization at 400°C annealing but more randomness after 600°C annealing.

DOPING AND GROWTH OF THIN Si EPILAYER AND SiGe BY UHV/CVD

2002 ◽  
Vol 16 (28n29) ◽  
pp. 4219-4223
Author(s):  
JINGYUN HUANG ◽  
LEI WANG ◽  
BINGHUI ZHAO ◽  
ZHIZHEN YE
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
X Ray Diffraction ◽  
Double Crystal ◽  
Abrupt Transition ◽  
X Ray ◽  
Si Substrates ◽  
Secondary Ion

The real time B-doped thin Si and SiGe epilayers on diameter 3-inch Si substrates were grown by an ultrahigh vacuum chemical vapor deposition (UHV/CVD) system. The substrate temperature during growth was from 550 ~ 780°C. The properties of the epilayers were characterized by secondary ion mass spectrum (SIMS), Fourier transform infrared spectroscopy (FTIR), spreading resistance profile (SRP) and double crystal x-ray diffraction (DCXRD). The carrier concentration in the intrinsic Si epilayer was about 1012 cm -3 and the resistivity was as high as about 10000 Ωcm. In addition, the abrupt transition and B-doped concentration of 1015 ~ 1019 cm -3 were achieved for Si and SiGe epilayers.

Variation of the Photoelectric Threshold of Boron Doped Diamond Films

1998 ◽  
Vol 509 ◽  
Author(s):  
I.A. Akwani ◽  
E.D. Sosa ◽  
J. Bernhard ◽  
S.C. Lim ◽  
R.E. Stallcup ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Polycrystalline Diamond ◽  
Boron Doping ◽  
Boron Doped Diamond ◽  
Si Substrates ◽  
Band Emission ◽  
Boron Doped ◽  
Photoelectric Threshold

AbstractBoron doped polycrystalline diamond films grown on p-type single-crystal Si substrates using chemical vapor deposition with a gas mixture of hydrogen, methane and diborane were characterized with scanning electron microscopy, X-ray photoelectron spectroscopy, ultraviolet photoelectron spectroscopy, Raman spectroscopy and photoelectric current measurements. The energy distributions are not sensitive to boron doping for diborane concentrations from 0 to 4.75 ppm, although the boron doping modifies the surface morphology and the photoemission intensity. The photoemission intensity is high where the microcrystalline content is highest (at diborane concentrations of 2.91 and 4.75 ppm. The photoelectric threshold is found to be at 4.38 eV, in agreement with earlier measurements. The present results are characteristic of valence band emission at 4.38, 4.63, 4.92, 5.12 and 5.30 eV for incident photons between 4.87 and 5.63 eV.

X-Ray Spectroscopic Studies of Organo-Metallic Vapor Phase Epitaxial Growth

1993 ◽  
Vol 312 ◽  
Author(s):  
S. Brennant ◽  
P. H. Fuosst ◽  
D. W. Kisker ◽  
F. J. Lamelast ◽  
P. Imperatori ◽  
...  
Keyword(s):  
Film Growth ◽  
Chemical Vapor ◽  
Spectroscopic Studies ◽  
Reactor Vessel ◽  
X Rays ◽  
X Ray ◽  
Structural Probe ◽  
X Ray Absorption ◽  
Structural Probes ◽  
Metallic Vapor

AbstractChemical Vapor Deposition often occurs under conditions unsuitable for simultaneous monitoring using electron-based structural probes. This is due to the near-atmospheric pressure which exists during growth. While some work has been performed using optical probes, the typically high temperatures in the reactor vessel and the vastly longer wavelength of visible light versus the features being studied has hampered its utility as a structural probe. Over the past several years x-rays from synchrotron storage rings have been used to study the surface structure of growing materials. These studies have been primarily scattering studies. In this paper we explore the use of x-ray spectroscopic studies for the analysis of film growth. We have focused on three areas: the measurement of reactor vessel profiles using x-ray fluorescence; The measurement of gas-phase Extended X-ray Absorption Fine Structure (EXAFS), and the measurement of EXAFS of adsorbed species on the substrates.

Defects in β-SiC thin films grown on α-SiC substrates

1988 ◽  
Vol 46 ◽  
pp. 568-569
Author(s):  
Karren L. More
Keyword(s):  
Thin Films ◽  
Semiconductor Device ◽  
Lattice Mismatch ◽  
Chemical Vapor ◽  
Substrate Material ◽  
Growth Interface ◽  
Si Substrates ◽  
Thermal Expansion Coefficients ◽  
Device Applications ◽  
Expansion Coefficients

Beta-SiC is an ideal candidate material for use in semiconductor device applications. Currently, monocrystalline β-SiC thin films are epitaxially grown on {100} Si substrates by chemical vapor deposition (CVD). These films, however, contain a high density of defects such as stacking faults, microtwins, and antiphase boundaries (APBs) as a result of the 20% lattice mismatch across the growth interface and an 8% difference in thermal expansion coefficients between Si and SiC. An ideal substrate material for the growth of β-SiC is α-SiC. Unfortunately, high purity, bulk α-SiC single crystals are very difficult to grow. The major source of SiC suitable for use as a substrate material is the random growth of {0001} 6H α-SiC crystals in an Acheson furnace used to make SiC grit for abrasive applications. To prepare clean, atomically smooth surfaces, the substrates are oxidized at 1473 K in flowing 02 for 1.5 h which removes ∽50 nm of the as-grown surface. The natural {0001} surface can terminate as either a Si (0001) layer or as a C (0001) layer.

Sign in / Sign up

Export Citation Format

Share Document