Evolution of Defect and Impurity Profile During High Dose Co Implantation into Si at Elevated Temperatures

1993 ◽  
Vol 320 ◽  
Author(s):  
S. Schippel ◽  
A. Witzmann
Keyword(s):  
Point Defects ◽  
Elevated Temperatures ◽  
Rutherford Backscattering Spectrometry ◽  
High Dose ◽  
Impurity Profile ◽  
Gaussian Shape ◽  
Near Surface ◽  
Gaussian Distributions ◽  
Transmission Electron ◽  
Effective Center

ABSTRACT<111> -Si was implanted with 250 keV Co ions at a target temperature of 350°C. The ion dose was varied between 1 × 1014 cm−2 and 2 × 1017 cm−2. The evolution of the defect and impurity profile was investigated by Rutherford Backscattering Spectrometry (RBS), channeling and transmission electron microscopy (TEM).Up to a dose of 1 × 1015 Co cm−2 no defects can be detected. At higher Co doses, we find correlated defects in the center of the Co distribution and point defects in the region below. Moreover, damage accumulation at the surface is observed. The concentration of defects increases with increasing ion dose and reaches its level of saturation at a dose of 2 × 1016 cm−2.The Co profiles of samples implanted at 350°C differ considerably from the Gaussian shape. The near surface and the back flank are parts of Gaussian distributions. However, the standard deviation of the near surface flank is always smaller than that of the back flank. Moreover, the distributions show tails into the substrate at depths > 320 nm. This proves that radiation damage acts as an effective center for the nucleation of CoSi2.During annealing we find a redistribution of Co towards the defective regions for Co doses between 1 × 1016 cm−2 and 5 × 1016 cm−2.

Evolution of Defect and Impurity Profile During High Dose Co Implantation into Si at Elevated Temperatures

1993 ◽  
Vol 316 ◽  
Author(s):  
S. Schippel ◽  
A. Witzmann
Keyword(s):  
Point Defects ◽  
Elevated Temperatures ◽  
Rutherford Backscattering Spectrometry ◽  
High Dose ◽  
Impurity Profile ◽  
Gaussian Shape ◽  
Near Surface ◽  
Gaussian Distributions ◽  
Transmission Electron ◽  
Effective Center

ABSTRACTȥ111Ɂ -Si was implanted with 250 keV Co ions at a target temperature of 350°C. The ion dose was varied between 1×1014 cm-2 and 2×1017 cm-2 . The evolution of the defect and impurity profile was investigated by Rutherford Backscattering Spectrometry (RBS), channeling and transmission electron microscopy (TEM).Up to a dose of 1 × 1015 Co cm-2 no defects can be detected. At higher Co doses, we find correlated defects in the center of the Co distribution and point defects in the region below. Moreover, damage accumulation at the surface is observed. The concentration of defects increases with increasing ion dose and reaches its level of saturation at a dose of 2 × 1016 cm-2.The Co profiles of samples implanted at 350°C differ considerably from the Gaussian shape. The near surface and the back flank are parts of Gaussian distributions. However, the standard deviation of the near surface flank is always smaller than that of the back flank. Moreover, the distributions show tails into the substrate at depths > 320 nm. This proves that radiation damage acts as an effective center for the nucleation of CoSi2.During annealing we find a redistribution of Co towards the defective regions for Co doses between 1 × 1016 cm-2 and 5× 1016 cm-2.

Dechannealing Study of Nanocrystalline Si:H Layers Produced by High Dose Hydrogen Irradiation of Silicon Crystals

1998 ◽  
Vol 536 ◽  
Author(s):  
V. P. Popov ◽  
A. K. Gutakovsky ◽  
I. V. Antonova ◽  
K. S. Zhuravlev ◽  
E. V. Spesivtsev ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Rutherford Backscattering Spectrometry ◽  
Nanocrystalline Structure ◽  
Structural Defects ◽  
High Dose ◽  
Silicon Crystals ◽  
Strong Energy ◽  
Transmission Electron ◽  
Hydrogen Implantation

AbstractA study of Si:H layers formed by high dose hydrogen implantation (up to 3x107cm-2) using pulsed beams with mean currents up 40 mA/cm2 was carried out in the present work. The Rutherford backscattering spectrometry (RBS), channeling of He ions, and transmission electron microscopy (TEM) were used to study the implanted silicon, and to identify the structural defects (a-Si islands and nanocrystallites). Implantation regimes used in this work lead to creation of the layers, which contain hydrogen concentrations higher than 15 at.% as well as the high defect concentrations. As a result, the nano- and microcavities that are created in the silicon fill with hydrogen. Annealing of this silicon removes the radiation defects and leads to a nanocrystalline structure of implanted layer. A strong energy dependence of dechanneling, connected with formation of quasi nanocrystallites, which have mutual small angle disorientation (<1.50), was found after moderate annealing in the range 200-500°C. The nanocrystalline regions are in the range of 2-4 nm were estimated on the basis of the suggested dechanneling model and transmission electron microscopy (TEM) measurements. Correlation between spectroscopic ellipsometry, visible photoluminescence, and sizes of nanocrystallites in hydrogenated nc-Si:H is observed.

Investigation of Pt Bottom Electrodes for "In-Situ" Deposited Pb(Zr,Ti)O3 (PZT) thin Films

1991 ◽  
Vol 243 ◽  
Author(s):  
Rainer Bruchhaus ◽  
Dana Pitzer ◽  
Oliver Eibl ◽  
Uwe Scheithauer ◽  
Wolfgang Hoesler
Keyword(s):  
Elevated Temperatures ◽  
Diffusion Processes ◽  
Rutherford Backscattering Spectrometry ◽  
Layer Sequence ◽  
Si Substrates ◽  
Transmission Electron ◽  
In Situ Deposition ◽  
Electron Spectrometry ◽  
Heating Up

AbstractThe deposition of the bottom electrode plays a key role in the fabrication of ferroelectric capacitors. Processing at elevated temperatures of up to 800°C can give rise to diffusion processes and thereof formation of harmful dielectric layers.In this paper we used Rutherford backscattering spectrometry (RBS), Auger electron spectrometry (AES) and transmission electron microscopy (TEM) to study Pt/Ti/SiO2/Si substrates with various thicknesses of the Ti and Pt layers. During heating up to about 450°C in vacuum the initial layer sequence remains unchanged. However, drastic changes occur when the electrodes are exposed to Ar/O2 atmosphere during heat treatment. Oxidation induced diffusion of Ti into Pt and oxidation of Ti were observed. A Pt electrode with a 100 nm thick Ti adhesion layer proved to be suitable for the "in-situ" deposition of PZT films.

scholarly journals Thermal Annealing of High Dose P Implantation in 4H-SiC

2019 ◽  
Vol 963 ◽  
pp. 399-402 ◽  
Author(s):  
Cristiano Calabretta ◽  
Massimo Zimbone ◽  
Eric G. Barbagiovanni ◽  
Simona Boninelli ◽  
Nicolò Piluso ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Raman Spectroscopy ◽  
Ion Implantation ◽  
Epitaxial Layer ◽  
Point Defects ◽  
High Dose ◽  
Double Step ◽  
Post Annealing ◽  
Transmission Electron

In this work, we have studied the crystal defectiveness and doping activation subsequent to ion implantation and post-annealing by using various techniques including photoluminescence (PL), Raman spectroscopy and transmission electron microscopy (TEM). The aim of this work was to test the effectiveness of double step annealing to reduce the density of point defects generated during the annealing of a P implanted 4H-SiC epitaxial layer. The outcome of this work evidences that neither the first 1 hour isochronal annealing at 1650 - 1700 - 1750 °C, nor the second one at 1500 °C for times between 4 hour and 14 hour were able to recover a satisfactory crystallinity of the sample and achieve dopant activations exceeding 1%.

Ion Beam Synthesis By Tungsten Implantation Into 6h-Silicon Carbide At Elevated Temperatures

1996 ◽  
Vol 423 ◽  
Author(s):  
Hannes Weishart ◽  
W. Matz ◽  
W. Skorupa
Keyword(s):  
Silicon Carbide ◽  
Tungsten Carbide ◽  
Elevated Temperatures ◽  
Rutherford Backscattering Spectrometry ◽  
Ion Beam ◽  
Bimodal Distribution ◽  
High Dose ◽  
Electrically Conductive ◽  
Implantation Temperature ◽  
High Dose Implantation

AbstractWe studied high dose implantation of tungsten into 6H-silicon carbide in order to synthesize an electrically conductive layer. Implantation was performed at 200 keV with a dose of 1×1017 W+cm−2 at temperatures of 90°C and 500°C. The samples were subsequently annealed either at 950°C or 1100°C. The influence of implantation and annealing temperatures on the reaction of W with SiC was investigated. Rutherford backscattering spectrometry (RBS), x-ray diffiraction (XRD) and Auger electron spectroscopy (AES) contributed to study the structure and composition of the implanted layer as well as the chemical state of the elements. The implantation temperature influences the depth distribution of C, Si and W as well as the damage production in SiC. The W depth profile exhibits a bimodal distribution for high temperature implantation and a customary gaussian distribution for room temperature implantation. Formation of tungsten carbide and silicide was observed in each sample already in the as-implanted state. Implantation at 90°C and annealing at 950°C lead to crystallization of W2C; tungsten silicide, however, remains amorphous. After implantation at 500°C and subsequent annealing at 11007deg;C crystalline W5Si3 forms, while tungsten carbide is amorphous.

Defect Pair Formation by Implantation-Induced Stresses in High-Dose Oxygen Implanted Silicon-on-Insulator Material

1993 ◽  
Vol 316 ◽  
Author(s):  
J.D. Lee ◽  
J.C. Park ◽  
D. Venables ◽  
S.J. Krause ◽  
P. Roitman
Keyword(s):  
Defect Density ◽  
Silicon On Insulator ◽  
Surface Strain ◽  
High Dose ◽  
X Ray Diffraction ◽  
Near Surface ◽  
X Ray ◽  
Density Reduction ◽  
Transmission Electron ◽  
Pair Density

ABSTRACTDefect microstructure and the near-surface strain of high-dose oxygen implanted silicon-on-insulator material (SIMOX) were investigated as a function of dose, implant temperature, and annealing temperature by transmission electron microscopy and high resolution x-ray diffraction. Dislocation half loops (DHLs) begin to form by stress assisted climb at a critical stress level due to implantation-induced damage. DHLs evolve into through-thickness defect (TTD) pairs by expansion during annealing. Both DHL and TTD-pair density increase with higher implant dose and lower implant temperature. Possible methods for defect density reduction are suggested based on the results of this study.

Conductive Tungsten-Based Layers Synthesized by Ion Implantation into 6H-Silicon Carbide

1996 ◽  
Vol 438 ◽  
Author(s):  
H. Weishart ◽  
J. Schoneich ◽  
M. Voelskow ◽  
W. Skorupa
Keyword(s):  
Silicon Carbide ◽  
Room Temperature ◽  
Depth Distribution ◽  
Ostwald Ripening ◽  
Rutherford Backscattering Spectrometry ◽  
High Dose ◽  
Electrically Conductive ◽  
Gaussian Shape ◽  
Implantation Temperature ◽  
High Dose Implantation

AbstractWe studied high dose implantation of tungsten into 6H-silicon carbide in order to synthesize an electrically conductive layer. Implantation was performed at 200 keV with a dose of 1.2x 1017 WIcm 2 at temperatures between 200°C and 400°C. The influence of implantation temperature on the distribution of W in SiC was investigated and compared to results obtained earlier from room temperature (RT) and 500°C implants. Rutherford backscattering spectrometry (RBS) was employed to study the structure and composition of the implanted layers. Implantation at temperatures between RT and 300°C did not influence the depth distribution of C, Si and W. The W depth profile shows a conventional Gaussian shape. Implanting at higher temperatures led to a more confined W rich layer in the SiC. This confinement is explained by Ostwald ripening which is enabled during implantation at temperatures above 300°C. The depth of the implantation induced damage decreases slightly with increasing implantation temperature, except for 400°C implantation. The amount of damage, however, is significantly reduced only for implantation at 500°C.

Ion Synthesis of Colloidal Silver Nanoclusters in the Organic Substrate

1995 ◽  
Vol 392 ◽  
Author(s):  
A. L. Stepanov ◽  
S. N. Abdullin ◽  
R. I. Khaibullin ◽  
V. F. Valeev ◽  
Yu. N. Osin ◽  
...  
Keyword(s):  
Surface Region ◽  
Organic Substrate ◽  
Silver Nanoclusters ◽  
High Dose ◽  
Near Surface ◽  
Organic Systems ◽  
Transmission Electron ◽  
Uv Visible ◽  
Average Size ◽  
Metallic Grains

AbstractHigh-dose ion implantation was used to create silver metallic grains in the epoxy resins The structure and optical properties of Ag/organic systems were investigated by transmission electron microscopy and absorption UV-visible spectroscopy, It was established that silver implantation into the organic substrate produced colloidal nanoclusters in the near-surface region, whose average size and size distribution were function of dose value. The silver nanoclusters give rise to optical absorption at the plasmon wavelength. and maximum absorption was shown to be correlated with filling factors. The d.c. resistivities of irradiated samples were measured in temperature range from 5 to 300 K The observed exp(T0/T)n behaviour of resistivity indicated that synthesized metal particles are separated.

Correlation of Void Formation with the Reduction of Carrier Activation and Anomalous Dopant Diffusion in Si-Implanted GaAs

1989 ◽  
Vol 163 ◽  
Author(s):  
Kei-Yu Ko ◽  
Samuel Chen ◽  
S. -Tong Lee ◽  
Longru Zheng ◽  
T.Y. Tan
Keyword(s):  
Carrier Concentration ◽  
Void Formation ◽  
Surface Region ◽  
High Dose ◽  
Near Surface ◽  
Transmission Electron ◽  
Severe Reduction ◽  
Normal Carrier ◽  
Spherical Voids ◽  
Diffusion Profiles

AbstractWe report the study of high-dose Si-implanted GaAs containing doses ranging from 1×1014 to 1×1015 cm-2 and with subsequent anneals at 850°C for 1 hour. At doses ≥ 3×1014 cm-2, a severe reduction of carrier concentration and anomalous Si diffusion are observed in the near-surface region. In the same region, small, near-spherical voids are found by transmission electron microscopy. In contrast, for samples implanted with doses ≤ 1×1014 cm-2, voids are not found, and both normal carrier activation and Si diffusion profiles are observed. The concurrent onset of these three phenomena in the same region in high-dose samples leads us to conclude that the severe reduction of carrier concentration and anomalous Si diffusion are attributable to the formation of voids.

Conductive Tungsten-Based Layers Synthesized by Ion Implantation Into 6H-Silicon Carbide

1996 ◽  
Vol 439 ◽  
Author(s):  
H. Weishart ◽  
J. schöneich ◽  
M. Voelskow ◽  
W. Skorupa
Keyword(s):  
Silicon Carbide ◽  
Room Temperature ◽  
Depth Distribution ◽  
Ostwald Ripening ◽  
Rutherford Backscattering Spectrometry ◽  
High Dose ◽  
Electrically Conductive ◽  
Gaussian Shape ◽  
Implantation Temperature ◽  
High Dose Implantation

AbstractWe studied high dose implantation of tungsten into 6H-silicon carbide in order to synthesize an electrically conductive layer. Implantation was performed at 200 keV with a dose of 1.2×1017 W+cm−2 at temperatures between 200°C and 400°C. The influence of implantation temperature on the distribution of W in SiC was investigated and compared to results obtained earlier from room temperature (RT) and 500°C implants. Rutherford backscattering spectrometry (RBS) was employed to study the structure and composition of the implanted layers. Implantation at temperatures between RT and 300°C did not influence the depth distribution of C, Si and W. The W depth profile shows a conventional Gaussian shape. Implanting at higher temperatures led to a more confined W rich layer in the SiC. This confinement is explained by Ostwald ripening which is enabled during implantation at temperatures above 300°C. The depth of the implantation induced damage decreases slightly with increasing implantation temperature, except for 400°C implantation. The amount of damage, however, is significantly reduced only for implantation at 500°C.

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