Amorphization of Silicon by Boron Ion Implantation

1986 ◽  
Vol 71 ◽  
Author(s):  
Y. Shih ◽  
J. Washburn ◽  
R. Gronsky ◽  
E.R. Weber
Keyword(s):  
Ion Implantation ◽  
Amorphous Silicon ◽  
Point Defects ◽  
Room Temperature ◽  
Liquid Nitrogen Temperature ◽  
Critical Energy ◽  
High Energy ◽  
Dose Rates ◽  
Initial Stage ◽  
Boron Ions

AbstractAmorphization of silicon due to implantation of boron ions which is the lightest element used for I.C. fabrication processes, has been systematically studied for various temperatures, voltages and dose rates. A model for formation of amorphous silicon by light ion implantation is proposed. It is suggested that accumulation of point defects and/or clusters is required at the initial stage of amorphization process. Diinterstitial -divacancy pairs are suggested to be the embryos of amorphous zones formed during implantation at room temperature. Out -diffusion of highly mobile interstitials during amorphization is thought to explain differences in the critical energy for amorphization with low and high energy implantation at liquid nitrogen temperature.

scholarly journals The Formation of Amorphous Silicon by Light Ion Damage

1985 ◽  
Vol 45 ◽  
Author(s):  
Y. Shih ◽  
J. Washburn ◽  
E.R. Weber ◽  
R. Gronsky
Keyword(s):  
Ion Implantation ◽  
Amorphous Silicon ◽  
Point Defect ◽  
Point Defects ◽  
Liquid Nitrogen Temperature ◽  
Paramagnetic Resonance ◽  
High Resolution Tem ◽  
Different Temperatures ◽  
Boron Ions ◽  
Point Defect Clusters

ABSTRACTA model for formation of amorphous silicon by light ion implantation is proposed. It is suggested that accumulation of point defects and/or complexes is required at the initial stage of the amorphization process. Amorphous zones can only form at the end of incoming light ion tracks when the pre-accumulated concentration of point defects reaches a critical value. Depending on the uniformity of the point defect distribution, two possibilities for the second stage of amorphization are suggested when ion implantation is performed at different temperatures.Silicon wafers implanted with boron ions below and above the critical amorphization dose at various temperatures have been investigated using cross section specimens in high resolution TEM. Complementary analyses of these specimens by Electron Paramagnetic Resonance have revealed the presence of dangling bonds in amorphous zones and point defect clusters. Extrinsic stacking faults with 1/3 <111> displacements and other smaller distortions with 1/x<111> displacements were also found to result from the amorphization process. Liquid nitrogen temperature was found to be necessary to cause complete amorphization of silicon by boron ion implantation.

Hydrogenation of B and P Implanted LPCVD Amorphous Silicon

1992 ◽  
Vol 258 ◽  
Author(s):  
Stanislaw M. Pietruszko
Keyword(s):  
Ion Implantation ◽  
Amorphous Silicon ◽  
Room Temperature ◽  
Silicon Films ◽  
Conductivity Measurements ◽  
Temperature Conductivity ◽  
Room Temperature Conductivity ◽  
B Doping ◽  
Doping Range

ABSTRACTThe results of the investigation of doping by B and P ion implantation into LPCVD amorphous silicon films in the range from 2*1015 to 2*1021 atoms/cm3 are presented. The room temperature conductivity increases to 10-2 Ω-1 cm-1 and to 10-2 Ω-1 cm-1 for the highest B and P doping, respectively. The subsequent hydrogenation (2.5 and 5 at%) by ion implantation increases the doping efficiency for P doping. For B doping efficiency increases at the low and decreases for the high doping range. The results of conductivity measurements vs temperature of doped and hydrogenated films are presented.

scholarly journals Photoluminescence Spectroscopy and Rutherford Backscattering Channeling Evaluation of Various Capping Techniques for Rapid Thermal Annealing of Ion-Implanted ZnSe

1994 ◽  
Vol 340 ◽  
Author(s):  
E.L. Allen ◽  
F.X. Zach ◽  
K.M. Yu ◽  
E.D. Bourret
Keyword(s):  
Optical Properties ◽  
Point Defects ◽  
Room Temperature ◽  
Annealing Temperature ◽  
Rutherford Backscattering Spectrometry ◽  
Liquid Nitrogen Temperature ◽  
Rutherford Backscattering ◽  
Photoluminescence Spectroscopy ◽  
Photoluminescence Spectra ◽  
Ion Implanted

ABSTRACTWe report on the effectiveness of proximity caps and PECVD Si3N4 caps during annealing of implanted ZnSe films. OMVPE ZnSe films were grown using diisopropylselenide (DIPSe) and diethylzinc (DEZn) precursors, then ion-implanted with 1 × 1014 cm−2 N (33 keV) or Ne (45 keV) at room temperature and liquid nitrogen temperature, and rapid thermal annealed at temperatures between 200°C and 850°C. Rutherford backscattering spectrometry in the channeling orientation was used to investigate damage recovery, and photoluminescence spectroscopy was used to investigate crystal quality and the formation of point defects. Low temperature implants were found to have better luminescence properties than room temperature implants, and results show that annealing time and temperature may be more important than capping material in determining the optical properties. The effects of various caps, implant and annealing temperature are discussed in terms of their effect on the photoluminescence spectra.

The Microstructual Characterization of Boron Ion Implanted Silicon During Amorphization Process

1985 ◽  
Vol 43 ◽  
pp. 302-303 ◽  
Author(s):  
Yih-Cheng Shih ◽  
Jack Washburn
Keyword(s):  
High Resolution ◽  
Ion Implantation ◽  
Cross Section ◽  
Heavy Ion ◽  
Transformation Process ◽  
Paramagnetic Resonance ◽  
Dose Rates ◽  
High Resolution Images ◽  
Boron Ions

Two amorphization models, heterogeneous and homogeneous nucleation have been used to describe heavy ion implantation at low temperature and light ion implantation at high temperature by many authors. However, the amorphization mechanism for light ion damage is still unclear. Cross section views of the amorphous-crystalline transition region afford a continuous picture of the crystalline to amorphous transformation process. In this work, high resolution cross-section TEM has been used to clarify the amorphization mechanism for silicon implanted with Boron ions at various temperatures and dose rates.A cross section view is shown in Fig. 1, of silicon implanted with 1x1016/cm2 Boron ions at room temperature and 80 KeV energy. It shows that small spots first gather around near the depth of peak damage (∼2300A below the surface). High resolution images of these spots reveals that they are damage zones losing periodic atom arrangement (Fig. 2). The Electron Paramagnetic Resonance Spectrum from the same specimen contains an isotropic amorphous peak.

Ion Implantation of Boron in Diamond

1988 ◽  
Vol 128 ◽  
Author(s):  
G. S. Sandhu ◽  
M. L. Swanson ◽  
W. K. Chu
Keyword(s):  
Optical Absorption ◽  
Ion Implantation ◽  
Natural Diamond ◽  
Liquid Nitrogen Temperature ◽  
Type Ii ◽  
Electrical Measurements ◽  
Boron Ions ◽  
Dopant Atoms ◽  
P Type ◽  
Diamond Type

ABSTRACTIt has been a challenge to inject dopant atoms onto diamond lattice sites by ion implantation, because of the complications of ion damage and defect clustering during annealing. We re-investigated this topic by implanting boron ions into an insulating natural diamond ( type II-A ) which was predamaged by carbon ion implantation. Both of the implantations were performed at liquid nitrogen temperature. The amount of pre-damage was adjusted to produce enough vacancies and interstitials in diamond to promote boron substitutionality during subsequent annealing. Samples were characterized by optical absorption and electrical measurements. It was found that optical absorption of the implanted samples strongly depends on the post implant annealing sequence. The activation energies obtained from electrical measurements match very closely to those due to boron atoms in natural p-type diamonds. Photoconductivity measurements showed that the fraction of remaining electrically active radiation defects in the implanted and annealed samples depends on the relative fluences of boron and carbon.

On The Formation of Si Oxide by Ion Implantation

1985 ◽  
Vol 45 ◽  
Author(s):  
F. Namavar ◽  
J.I. Budnick ◽  
F.H. Sanchez ◽  
H.C. Hayden
Keyword(s):  
Ion Implantation ◽  
Liquid Nitrogen ◽  
Room Temperature ◽  
Experimental Situation ◽  
Liquid Nitrogen Temperature ◽  
Excess Oxygen ◽  
Implantation Temperature ◽  
Current Densities

ABSTRACTOxygen 0+ ions have been implanted into Si both at room temperature and liquid nitrogen temperature in order to determine the effect of implantation temperature on SiO2 formation. Samples were analysed by RBS with 1.5 MeV He+ ions. The implants of 0+ in Si were done at 150 keV with current densities of ≤10 μA/cm2. For doses of more than 1.5×1018 0+/cm2, in-situ RBS experiments positively indicate a 2:1 oxygen silicon ratio. Increased 0+ doses (for both room temperature and liquid nitrogen temperature) cause the Si02 layers to spread uniformly and symmetrically toward both the surface and the interior. From these results, it is apparent that excess oxygen diffuses toward Si/Si02 interfaces in our experimental situation even at liquid nitrogen temperature.

The New Study Based on a Dual Ion Implantation PSD Structure

2015 ◽  
Vol 1096 ◽  
pp. 503-508
Author(s):  
Qian Li ◽  
Tian Ze Li ◽  
Xiang Peng Chen
Keyword(s):  
Ion Implantation ◽  
High Energy ◽  
High Dose ◽  
Position Resolution ◽  
High Position ◽  
Traditional Structure ◽  
New Type ◽  
Position Sensitive ◽  
Boron Ions ◽  
Implantation Method

In the analysis of semiconductor position sensitive detector (PSD) based on the traditional structure, using dual ion implantation method to studying the new type of PSD structure. The new structure of the n-type silicon substrate by implanting a high dose, low energy boron ions and another high energy boron ion, Which subsequent annealing of 2h at 1050 °C in an ambient of dry O2to form a shallow and a low doped p-n junction. Experimental results show that the new structure of PSD can obtained high position resolution, smaller errors and nonlinear response time.

Effect of Ion-Implantation on the Microstructure of Si3N4 Based Ceramics

2005 ◽  
Vol 290 ◽  
pp. 234-237
Author(s):  
J.K. Babcsán ◽  
Maria Berkes Maros ◽  
N. Wanderka ◽  
D. Klaffke ◽  
Helmut Schubert
Keyword(s):  
Ion Implantation ◽  
Room Temperature ◽  
Amorphous Layer ◽  
Diffraction Measurement ◽  
Wear Coefficient ◽  
Transmission Electron ◽  
Initial Stage ◽  
The Coefficient Of Friction ◽  
Electron Diffraction Measurement ◽  
Wear Tests

Si3N4 based ceramics that made by hot isostatic press, were implanted at room temperature with N+ - and C+ - ions with energy of 500 keV and 2 MeV, respectively. The specimens were irradiated at a fluence of 1017 ion/cm2. The microstructure changes after ionimplantation in the surface layer were investigated by transmission electron microscopy (TEM). The effect of ion-implantation on the tribological properties was also studied. After N+ and C+ ionimplantation an amorphous layer near to the surface has been formed which was observed by electron diffraction measurement. The wear tests were performed by means of a ball-on-disk configuration using commercially available Si3N4 ball. The friction coefficient was measured online, the wear coefficient was determined on the base of the wear scar sizes. The specific wear rate was reduced by N+-implantation and the coefficient of friction was lower in the initial stage in both cases.

Influence of the Temperature of Implantation on the Morphology of Defects in MeV Implanted GaAs.

1989 ◽  
Vol 147 ◽  
Author(s):  
G. Braunstein ◽  
Samuel Chen ◽  
S.-Tong Lee ◽  
G. Rajeswaran.
Keyword(s):  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Point Defects ◽  
Room Temperature ◽  
Surface Region ◽  
Amorphous Region ◽  
Liquid Nitrogen Temperature ◽  
Dislocation Loops ◽  
Near Surface ◽  
Epitaxial Regrowth

AbstractWe have studied the influence of the temperature of implantation on the morphology of the defects created during 1-MeV implantation of Si into GaAs, using RBS-channeling and TEM. The annealing behavior of the disorder has also been investigated.Implantation at liquid-nitrogen temperature results in the amorphization of the implanted sample for doses of 2×1014 cm−2 and larger. Subsequent rapid thermal annealing at 900°C for 10 seconds leads to partial epitaxial regrowth of the amorphous layer. Depending on the implantation dose, the regrowth can proceed from both the front and back ends of the amorphous region or only from the deep end of the implanted zone. Nucleation and growth of a polycrystalline phase occurs concurrently, limiting the extent of the epitaxial regrowth. After implantation at room temperature and above, two distinct types of residual defects are observed or inferred: point defect complexes and dislocation loops. Most of the point defects disappear after rapid thermal annealing at temperatures ≥ 700°C. The effect of annealing on the dislocation loops depends on the distance from the surface of the sample. Those in the near surface region disappear upon rapid thermal annealing at 700°C, whereas the loops located deeper in the sample grow in size and begin to anneal out only at temperatures in excess of 900°C. Implantation at temperatures of 200 - 300°C results in a large reduction in the number of residual point defects. Subsequent annealing at 900°C leads to a nearly defect-free surface region and, underneath that, a buried band of partial dislocation loops similar to those observed in the samples implanted at room temperature and subsequently annealed.

Stability and Relaxation of Point Defects in amorphous silicon

1992 ◽  
Vol 279 ◽  
Author(s):  
Raymond Lutz ◽  
Laurent J. Lewis
Keyword(s):  
Molecular Dynamics ◽  
Low Temperature ◽  
Amorphous Silicon ◽  
Point Defects ◽  
Room Temperature ◽  
Empirical Potential ◽  
The Stability

ABSTRACTWe have used molecular-dynamics to investigate the stability and relaxation of point defects — vacancies and interstitials — in a model of amorphous silicon, with the interactions between atoms described by the Stillinger-Weber empirical potential. The annihila-tion of point defects has been proposed as an important mechanism by which relaxation proceeds in amorphous silicon. Starting with a Wooten-Winer-Weaire model of a-Si, we “manually” create vacancies in the structure by removing a number of randomly-selected four-fold coordinated atoms. The system is then allowed to relax. Our calculations reveal unambiguously that, of a number of vacancies introduced in the model at low temperature, roughly a third are stable; these anneal out upon heating at room temperature. The vacancies seem, in most cases, to consist of a relatively large empty volume bounded by four atoms of which at least one is undercoordinated. Our study of interstitials seems to indicate that they diffuse through a “jump-and-bump” process, eventually annihilating when a large enough, properly coordinated, vacant volume is encountered.

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