Anisotropic Dry Etching of S1O2 on Si and its Impact on Surface and Near-Surface Properties of the Substrate.

1986 ◽  
Vol 68 ◽  
Author(s):  
G. S. Oehrlein ◽  
G. J. Coyle ◽  
J. C. Tsang ◽  
R. M. Tromp ◽  
J. G. Clabes ◽  
...  
Keyword(s):  
Raman Scattering ◽  
Surface Properties ◽  
Surface Region ◽  
Dry Etching ◽  
High Concentration ◽  
Photoelectron Emission ◽  
Plasma Exposure ◽  
Near Surface ◽  
Ion Channeling ◽  
Fluorocarbon Film

AbstractIn the present paper structural and chemical changes which can occur in the surface and near-surface properties of the substrate during anisotropic dry etching of SiO2 on Si will be reviewed.Silicon specimens which had been etched in CF4/X%H2 (X≤40) have been characterized by X-ray photoelectron emission spectroscopy, He ion channeling, H profiling and Raman scattering techniques.Key results of our studies are summarized as follows: Plasma exposure of a Si surface leads to the deposition of a thin (≤50Å thick) C,F-film.A Si-carbide containing Si region is formed during RIE which is localized near the fluorocarbon-film/Si interface.The near-surface region (∼30–50Å) of the Si substrate is also heavily disordered as found by ion channeling and Raman scattering.A modified, less damaged Si region has been found in the case of hydrogen-based etching gases, which extends from about 30–50Å from the surface to a depth in extent of 250Å and contains a high concentration (∼ 5 at.%) of H as shown by hydrogen profiling techniques.From the observation of Si-H and Si-H2 vibrational modes by Raman scattering it has been shown that some of the H is bonded to the Si lattice.

Heteroepitaxial Growth Of ZnO Films BY PLD

1997 ◽  
Vol 474 ◽  
Author(s):  
R. D. Vispute ◽  
V. Talyansky ◽  
Z. Trajanovic ◽  
S. Choopun ◽  
M. Downes ◽  
...  
Keyword(s):  
Oxygen Pressure ◽  
Surface Region ◽  
Optical Quality ◽  
Degree Of Crystallinity ◽  
Zno Films ◽  
Heteroepitaxial Growth ◽  
Near Surface ◽  
Ion Channeling ◽  
Deposition Parameters ◽  
High Degree

ABSTRACTHere we present our recent work on the fabrication of high crystalline and optical quality ZnO films on sapphire (001) by pulsed laser deposition. The influence of deposition parameters such as the substrate temperature, oxygen pressure, laser fluence, and pulse repetition rate on the crystalline quality of ZnO layers has been studied. The Ω-rocking curve FWHM of the (002) peak for the films grown at 750°, oxygen pressure 10−5 Torr was 0.17°. The XRD-Ф scans studies revealed that the films were epitaxial with a 30° rotation of the unit cell with respect to the sapphire to achieve a low energy configuration for epitaxial growth. The high degree of crystallinity was confirmed by ion channeling technique providing a minimum Rutherford backscattering yield of 2–3% in the near surface region (-2000Å). The atomic force microscopy revealed smooth hexagonal faceting of the films. The optical absorption edge measured by UV-Visible spectroscopy was sharp at 383 nm. Excellent crystalline properties of these epi-ZnO/sapphire heterostractures are thus promising for III-V nitride heteroepitaxy.

THE SURFACE STRUCTURE OF A LOW Pd Cu/Pd-(110) CRYSTAL ALLOY

1994 ◽  
Vol 01 (04) ◽  
pp. 569-571 ◽  
Author(s):  
M. BOWKER ◽  
M. NEWTON ◽  
S.M. FRANCIS ◽  
M. GLEESON ◽  
C. BARNES
Keyword(s):  
Surface Structure ◽  
Surface Region ◽  
Single Scattering ◽  
Alloy Surface ◽  
High Concentration ◽  
Near Surface ◽  
X Ray ◽  
Photoelectron Diffraction ◽  
Layer 2

X-ray photoelectron diffraction studies of this alloy surface have been carried out and indicate that there is a significant expansion of the lattice in the near-surface region due to the high concentration of Pd in layer 2. Preliminary single scattering calculations lend support to this proposal for the surface structure, and place this expansion in the subsurface mainly between layers 2 and 3.

Plasma-Surface Interaction Limits for Remote H-Plasma Cleaning of Si(100)

1992 ◽  
Vol 259 ◽  
Author(s):  
T.P. Schneider ◽  
B.L. Bernhard ◽  
Y.L. Chen ◽  
R.J. Nemanich
Keyword(s):  
Optical Emission ◽  
Surface Region ◽  
Rf Plasma ◽  
Plasma Cleaning ◽  
Plasma Exposure ◽  
Plasma Parameters ◽  
Near Surface ◽  
Platelet Defects ◽  
C 50 ◽  
Rf Plasma Cleaning

ABSTRACTAn investigation of the parameters in H-plasma cleaning influencing H-diffusion and surface etching is described. The Si surface and subsurface regions were characterized with Raman spectroscopy and high resolution transmission electron microscopy (HRTEM), and the plasma parameters were monitored with a double Langmuir probe and optical emission spectroscopy. The parameters varied in the rf plasma cleaning were the substrate temperature, the rf power, and the plasma exposure time. It was found that low pressure and low power H-plasma exposure was effective in terms of cleaning the surface. In the 300°C, 20 Watts, 2 min. H-plasma exposure case, the Raman spectra indicated that there was no detectable H incorporation into the Si bulk and HRTEM showed no obvious defect microstructure in the near surface region and that the surface was smooth. In contrast, in the 150°C, 50 Watts, 60 min. H-plasma exposure case, HRTEM indicated that H-induced platelet defects formed in the Si(100) subsurface region and that the surface morphology was rough. Raman scattering revealed Si-H features at ∼2100 cm−1.

Ion Beam Induced Modifications of Biocompatible Polymer

2015 ◽  
Vol 239 ◽  
pp. 149-160
Author(s):  
A.M. Abdul-Kader ◽  
Andrzej Turos
Keyword(s):  
Friction Coefficient ◽  
Surface Properties ◽  
Rutherford Backscattering Spectrometry ◽  
Ion Beam ◽  
Chemical Properties ◽  
Surface Region ◽  
Ion Bombardment ◽  
Hydrogen Release ◽  
Nuclear Reaction Analysis ◽  
Near Surface

Ion beam bombardment has shown great potential for improving the surface properties of polymers. In this paper, the ion beam-polymer interaction mechanisms are briefly discussed. The main objective of this research was to study the effects of H-ion beam on physico-chemical properties of Ultra-high-molecular-weight polyethylene (UHMWPE) as it is frequently used in biomedical applications. UHMWPE was bombarded with 65 keV H-ions to fluences ranging from 1x1014–2x1016 ions/cm2. Changes of surface layer composition produced by ion bombardment of UHMWPE samples were studied. The hydrogen release and oxygen uptake induced by ion beam bombardment were determined by Nuclear reaction analysis (NRA) using the 1H(15N, αγ)12C and Rutherford backscattering spectrometry (RBS), respectively. Tribological and hardness properties at the polymer near surface region were studied by means of friction coefficient and micro-hardness testers, respectively. Wettability of the bombarded surfaces was determined by measuring the contact angle for distilled water. The obtained results showed that the ion bombardment induced hydrogen release increases with the increasing ion fluence. An important effect observed, was the rapid oxidation of samples, which occurs after exposure of bombarded samples to air. These effects resulted in important modifications of the surface properties of bombarded material such as change of friction coefficient, hardness and improved wettability.

Solid-phase epitaxy of ion-implanted LiNbO3 for optical waveguide fabrication

1987 ◽  
Vol 2 (2) ◽  
pp. 222-230 ◽  
Author(s):  
Ch. Buchal ◽  
P. R. Ashley ◽  
B. R. Appleton
Keyword(s):  
Optical Waveguides ◽  
Solid Phase ◽  
Surface Region ◽  
Liquid Nitrogen Temperature ◽  
High Concentration ◽  
Near Surface ◽  
Crystalline Substrate ◽  
A New Technique ◽  
Waveguide Fabrication ◽  
Water Saturated

A new technique for successfully fabricating high-quality optical waveguides in LiNbO3 is reported. A high concentration of Ti is implanted with the substrate at liquid nitrogen temperature and an amorphous, Ti-rich, nonequilibrium phase is produced in the implanted, near-surface region. Subsequent thermal annealing in water-saturated oxygen atmosphere at up to 1000°C initiates solid-phase epitaxial regrowth onto the crystalline substrate. A highquality single crystalline layer results that is rich in Ti and has excellent waveguiding properties.

Gettering of Cu at Buried Damage Layers Made by Si Self Implantation

1989 ◽  
Vol 157 ◽  
Author(s):  
J.R. Liefting ◽  
R.J. Schreutelkamp ◽  
W.X. Lu ◽  
F.W. Saris
Keyword(s):  
Surface Layer ◽  
Thermal Annealing ◽  
Rutherford Backscattering Spectrometry ◽  
Surface Region ◽  
Amorphous Layer ◽  
High Concentration ◽  
Near Surface ◽  
Before And After ◽  
Dose Ranging ◽  
P Type

ABSTRACTChanneled implants have been performed with lOOkeV 28Si+ into p-type Si(100) to obtain a buried amorphous layer. Before and after recrystallization of the a-Si layer, Cu was implanted at an energy of 15 keV and a dose ranging from 5E13 to 1E15 I cm2- to obtain a high concentration of Cu in the near surface region. Also, Cu implants were performed into virgin Si for comparison. After Cu implantation, thermal annealing was performed at temperatures between 490 °C and 900 °C for 10 min. to 320 min. Cu profiles before and after annealing were studied with Rutherford Backscattering Spectrometry and channeling analysis. For the case where Cu was implanted after recrystallization of the buried amorphous layer, Cu was gettered at the position where the ale interfaces met during recrystallization. For the case where Cu was implanted before recrystallization, Cu diffused towards the buried a-Si region upon annealing and was trapped inside the recrystallizing buried amorphous layer. The results show that buried damage layers can effectively getter Cufrom the Si surface layer and gettering is most efficient at 600 °C.

Effects of sequential He+ and Ar+ implantation on surface properties of polymers

1996 ◽  
Vol 11 (10) ◽  
pp. 2661-2667 ◽  
Author(s):  
Gopal R. Rao ◽  
Eal H. Lee
Keyword(s):  
Wear Resistance ◽  
Surface Properties ◽  
Ion Irradiation ◽  
Surface Hardness ◽  
Wear Test ◽  
Surface Region ◽  
Near Surface ◽  
Ether Ether Ketone ◽  
Poly Ether Ether Ketone ◽  
Hardness Increase

Three important polymers: polystyrene (PS), poly ether ether ketone (PEEK), and polyimide Kapton, were irradiated separately with 1 MeV He+, 1 MeV Ar+, and 1 MeV He+ followed by 1 MeV Ar+ sequentially, to a fluence of 3 × 1019 ions/m2 for each ion. The specimens were characterized for changes in surface hardness using a nanoindentation technique, and wear resistance using a reciprocating sliding wear apparatus with a steel ball counterface. Results indicated that while all polymers showed higher hardness values after ion irradiation, the dual irradiation resulted in the largest hardness increase, greater than for the single ion-irradiated specimens. Wear test results also indicated that the dual He+ + Ar+ irradiation resulted in the best improvement in wear resistance of the polymers. These improvements in properties are a consequence of cross-linking of the polymer material caused by the ion irradiation. Linear energy transfer considerations showed that the dual He+ + Ar+ implantation was better because it combined a deeper implant, in the form of He, along with Ar irradiation which resulted in a shallower but more highly cross-linked layer at the near surface. Thus a deeper and graded cross-linked surface region was formed. The study shows that there is greater flexibility for tailoring surface properties of polymers by using a judicious combination of ion species, ion energies, and fluences.

scholarly journals Ion Implantation and Annealing of SrTiO3 and CaTiO3

1987 ◽  
Vol 93 ◽  
Author(s):  
C. W. White ◽  
L. A. Boatner ◽  
J. Rankin ◽  
M. J. Aziz
Keyword(s):  
Ion Implantation ◽  
Solid Phase ◽  
Surface Region ◽  
Single Crystal Substrate ◽  
Recrystallization Process ◽  
Near Surface ◽  
Ion Channeling ◽  
Implantation Damage ◽  
Crystal Substrate ◽  
Kinetics Of

ABSTRACTIon implantation damage and thermal annealing results are presented for single crystals of SrTiO3 and CaTiO3. The near-surface region of both of these materials can be made amorphous by low doses (∼1015/cm2 ) of heavy ions (Pb at 540 keV). During annealing, the amorphous implanted region crystallizes epitaxially on the underlying single-crystal substrate. The kinetics of this solid-phase epitaxial recrystallization process have been measured by employing ion channeling techniques.

Damage Accumulation in MgAl2O4 Crystals by Xe Ion Irradiations

1993 ◽  
Vol 316 ◽  
Author(s):  
N. Yu ◽  
M. Nastasi ◽  
M.G. Hollander ◽  
C.R. Evans ◽  
C.J. Maggiore ◽  
...  
Keyword(s):  
Temperature Effect ◽  
Damage Accumulation ◽  
Rutherford Backscattering Spectrometry ◽  
Surface Region ◽  
Irradiation Damage ◽  
Spinel Layer ◽  
Near Surface ◽  
Ion Channeling ◽  
Significant Temperature

ABSTRACTWe have studied the damage kinetics in single crystal MgAl2O4 (spinel) with (100) orientation under 370 keV Xe ion irradiations at temperatures of -100 and 400 C. In-situ Rutherford Backscattering Spectrometry (RBS) and ion channeling have been used to monitor the damage accumulation in spinel following sequential Xe ion irradiations. A significant temperature effect on the irradiation damage has been found. Channeling data show that at -100 C, the irradiated spinel layer reaches the same level as in a random spectrum at a dose of 8×1015 Xe/cm2 (20 DPA for peak damage), while at 400 C, the near surface region (50 nm) remains single-crystalline up to 2×1016 Xe/cm2.

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