Journal articles: 'Concentration impurete'

1

Inoue, Kaihei, Yuki Tokumoto, Kentaro Kutsukake, Yutaka Ohno, and Ichiro Yonenaga. "Growth of Heavily Indium Doped Si Crystals by Co-Doping of Neutral Impurity Carbon or Germanium." Key Engineering Materials 508 (March 2012): 220–23. http://dx.doi.org/10.4028/www.scientific.net/kem.508.220.

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Czochralski Growth of Si Crystals Heavily Doped with in Impurity and Co-Doped with Electrically Neutral Impurity C or Ge Was Conducted in Order to Investigate the Solubility and Ionization Ratio of in in Si for Utilizing in Advanced ULSI and PV Devices. The Carrier Concentrations in the Grown in-Doped and (In+C) and (In+Ge) Co-Doped Crystals Were in a Range of 3.5~6.5 × 1016 Cm-3, much Lower than the Total Concentration of in Impurity due to the Low Ionization Ratio. Sufficient Increase of Carrier Concentrations by Co-Doping of C or Ge Impurity Was Not Detected for their Low Concentrations in the Grown Crystals Investigated.

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Chen, Shih-Jui, Yi-Li Chen, Yu-Jui Chang, Dong-Lin Chuang, Yi-Chun Chen, Hai-Ping Tsui, and Yean-Ren Hwang. "Measurement of Electrical Discharge Machining Oil Quality by Analyzing Variations in the Equivalent Relative Permittivity of the Capacitive Sensor." Sensors 20, no. 21 (November 2, 2020): 6248. http://dx.doi.org/10.3390/s20216248.

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In this study, a concentration monitoring system was successfully developed. A sensor was immersed in electrical discharge machining oil, and the capacitance of the sensor changed as a function of the impurity concentration. Thus, DC voltage variations were produced via a conversion circuit. Carbon black and iron particles with different concentrations were successfully characterized. The capacitance increments were positively correlated with the particle concentration. The linear fitting results based on the impurity concentration were used to express the degree of influence of particles with different weight percentage concentrations on the increase in the overall capacitance value. An equivalent medium theory model was then developed according to the electrical characteristics of the impurities to predict different particle volume percentages.

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Al, E. B., F. Ungan, U. Yesilgul, E. Kasapoglu, H. Sari, and I. Sökmen. "Infrared transitions between hydrogenic states in GaInNAs/GaAs quantum wells." International Journal of Modern Physics B 30, no. 22 (September 6, 2016): 1650139. http://dx.doi.org/10.1142/s0217979216501393.

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The effects of nitrogen and indium concentrations on the [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text]-like donor impurity energy states in a single [Formula: see text] quantum well (QW) are investigated by variational approach within the effective mass approximation. The results are presented as a function of the well width and the donor impurity position. It is found that the impurity binding and transition energies depend strongly on the indium concentration while depends weakly on the nitrogen concentration.

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Zhang, Sui-Shuan, Zong-Yan Zhao, and Pei-Zhi Yang. "Analysis of electronic structure and optical properties of N-doped SiO2 based on DFT calculations." Modern Physics Letters B 29, no. 19 (July 20, 2015): 1550100. http://dx.doi.org/10.1142/s0217984915501006.

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The crystal structure, electronic structure and optical properties of N-doped [Formula: see text] with different N impurity concentrations were calculated by density function theory within GGA[Formula: see text]+[Formula: see text]U method. The crystal distortion, impurity formation energy, band gap, band width and optical parameter of N-doped [Formula: see text] are closely related with N impurity concentration. Based on the calculated results, there are three new impurity energy levels emerging in the band gap of N-doped [Formula: see text], which determine the electronic structure and optical properties. The variations of optical properties induced by N doping are predominately determined by the unsaturated impurity states, which are more obvious at higher N impurity concentration. In addition, all the doping effects of N in both [Formula: see text]-quartz [Formula: see text] and [Formula: see text]-quartz [Formula: see text] are very similar. According to these findings, one could understand the relationship between nitrogen concentration and optical parameter of [Formula: see text] materials, and design new optoelectrionic Si–O–N compounds.

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Velichko, O. I. "On concentration dependence of arsenic diffusivity in silicon." International Journal of Computational Materials Science and Engineering 05, no. 01 (March 2016): 1650005. http://dx.doi.org/10.1142/s2047684116500056.

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An analysis of the equations used for modeling thermal arsenic diffusion in silicon has been carried out. It was shown that for arsenic diffusion governed by the vacancy-impurity pairs and the pairs formed due to interaction of impurity atoms with silicon self-interstitials in a neutral charge state, the doping process can be described by the Fick’s second law equation with a single effective diffusion coefficient which takes into account two impurity flows arising due to interaction of arsenic atoms with vacancies and silicon self-interstitials, respectively. Arsenic concentration profiles calculated with the use of the effective diffusivity agree well with experimental data if the maximal impurity concentration is near the intrinsic carrier concentration. On the other hand, for higher impurity concentrations a certain deviation in the local regions of arsenic distribution is observed. The difference from the experiment can occur due to the incorrect use of effective diffusivity for the description of two different impurity flows or due to the formation of nonuniform distributions of neutral vacancies and neutral self-interstitials in heavily doped silicon layers. We also suppose that the migration of nonequilibrium arsenic interstitial atoms makes a significant contribution to the formation of a low concentration region on thermal arsenic diffusion.

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Tanaka, Daiki, Wei Fang Lu, Satoshi Kamiyama, Motoaki Iwaya, Tetsuya Takeuchi, and Isamu Akasaki. "Photoluminescence Characterization of Fluorescent Sic with High Boron and Nitrogen Concentrations." Materials Science Forum 1004 (July 2020): 265–71. http://dx.doi.org/10.4028/www.scientific.net/msf.1004.265.

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The dependence of optical properties on impurity concentrations and excitation power was explored. In particular, it was found that the peak shift of photoluminescence (PL) is proportional to the boron concentration. This might be due to donor–acceptor pair (DAP) recombination via double deep acceptor levels (D-centers), where the occupancy of the D*-center increased with the B concentration, and the recombination via the D*-center for longer wavelengths became dominant. Moreover, the relative constants B and C were calculated by BC model fitting from the internal quantum efficiency (IQE) curve as a function of excitation power. The theoretical extrapolation based on BC model predicted that high impurity concentrations are sufficient to suppress the droop phenomenon of efficiency induced by the increased excitation power.

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7

Franc, J., H. Elhadidy, V. Babentsov, A. Fauler, and M. Fiederle. "Comparative study of vertical gradient freeze grown CdTe with variable Sn concentration." Journal of Materials Research 21, no. 4 (April 1, 2006): 1025–32. http://dx.doi.org/10.1557/jmr.2006.0117.

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Four CdTe ingots with gradually increased concentration of the Sn impurity have been grown by the vertical gradient freeze method and were characterized with glow discharge mass spectroscopy, photoinduced current transient spectroscopy, resistivity, photoconductivity, and photoluminescence techniques. It was shown that the Sn impurity strongly influences resistivity and photoconductivity of the material. Concentration of Sn must be higher than the total concentration of residual acceptors to reach strong compensation. The middle-gap donor level pins the Fermi-level. Photoconductive high resistivity material can be prepared with Sn concentrations in the melt in the range 1018–1019 cm−3. In total, 6 electron traps and 3 hole traps were identified in the band gap by several complementary techniques.

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8

Benzaquen, M., D. Walsh, and J. Auclair. "Auto-épitaxie et propriétés d'As–Ga obtenu par épitaxie en phase vapeur à partir de composés organo-métalliques." Canadian Journal of Physics 63, no. 6 (June 1, 1985): 732–35. http://dx.doi.org/10.1139/p85-116.

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Lightly compensated epitactic n-type GaAs is obtained by metal-organic vapour-phase epitaxy (MOVPE) with free-carrier concentration in the low 1015 cm−3 range and with good uniformity of both thickness and impurity concentrations over a 2-in.-diameter area (1 in. = 2.54 cm). Detailed Hall-effect and photoluminescence measurements are reported. At temperatures below 8 K, the conductivity is governed by variable-range hopping, clearly indicating a band of localized donor states. At higher impurity concentrations, a metallic contribution to the conductivity suggests a buildup of extended states near the middle of this band. These results are consistent with the observed photoluminescence.

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9

Girrens, S. P., and F. W. Smith. "Constituent Diffusion in a Deformable Thermoelastic Solid." Journal of Applied Mechanics 54, no. 2 (June 1, 1987): 441–46. http://dx.doi.org/10.1115/1.3173034.

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Solid mixtures containing initially uniform dilute concentrations of impurity elements may, upon the application of mechanical and thermal loading, develop regions of high impurity concentration that could result in local degradation of material properties. To address these degradation processes, a fully coupled thermomechanical-diffusion theory has been developed to describe the mass transport of mobile constituents driven by gradients in concentration, strain dilatation and temperature in a solid deformable parent material. A finite element code has been assembled to solve plane transient thermomechanical-diffusion problems. The theory presented and the resulting code have been successfully used to model internal hydrogen redistribution in β-phase Ti alloys induced by elastic strain gradients during bending.

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10

Plukienė, Rita, Elena Lagzdina, Laurynas Juodis, Artūras Plukis, Andrius Puzas, Rasa Gvozdaitė, Vidmantas Remeikis, et al. "Investigation of Impurities of RBMK Graphite by Different Methods." Radiocarbon 60, no. 6 (November 19, 2018): 1861–70. http://dx.doi.org/10.1017/rdc.2018.93.

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ABSTRACTSamples of graphite from a RBMK-1500 reactor at the Ignalina Nuclear Power Plant from different construction elements (stack, sleeve, and bushing) were analyzed by the instrumental neutron activation analysis (INAA) method (LVR-15 experimental reactor of the Research Centre Řež, Ltd.) using the prompt gamma activation analysis (PGAA) method (Heinz Maier-Leibnitz Zentrum) and with an inductively coupled plasma mass spectrometer (ICP-MS) (CPST, Lithuania). These measurements were performed with the aim of obtaining the missing information on the impurity distribution in the RBMK-type nuclear graphite constructions as well as for intercomparison purposes, with the results measured in the graphite sleeve samples previously obtained by INAA & GDMS (Glow Discharge Mass Spectrometry) at CEA Saclay, France, and ICP-MS (CPST, Lithuania) methods. Validation of the ICP-MS method for the nuclear graphite impurity concentration determination was proven. The experimentally obtained RBMK-1500 graphite impurity values in different graphite constructions were compared with other measurements and new limits of the possible maximal concentrations of nuclear RBMK graphite impurity concentrations were obtained.

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11

Karel, Miloslav, and Jaroslav Nývlt. "Effect of Impurities on the Width of the Metastable Region of Potassium Sulfate." Collection of Czechoslovak Chemical Communications 58, no. 9 (1993): 1997–2002. http://dx.doi.org/10.1135/cccc19931997.

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The width of the metastable region of potassium sulfate was measured in the presence of various concentrations of chromate, copper(II) and aluminium ions. The dependence of the metastable region width on the impurity concentration is generally nonlinear and in some cases even changes its nature; while in low concentrations some impurities make the metastable region narrower, they make it broader if present in higher concentrations. The effect of the impurities increases in order K2Cr2O7 - CuSO4 - Al2(SO4)3.

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12

Suzuki, Kunihiro. "High concentration impurity diffusion profile model." Solid-State Electronics 44, no. 3 (March 2000): 457–63. http://dx.doi.org/10.1016/s0038-1101(99)00270-1.

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13

Henry, A., O. Kordina, C. Hallin, C. Hemmingsson, and E. Janzén. "Impurity concentration determination in 6H-SiC." Solid State Communications 93, no. 5 (February 1995): 465. http://dx.doi.org/10.1016/0038-1098(95)80043-3.

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14

Freitag, Johannes, Sepp Kipfstuhl, Thomas Laepple, and Frank Wilhelms. "Impurity-controlled densification: a new model for stratified polar firn." Journal of Glaciology 59, no. 218 (2013): 1163–69. http://dx.doi.org/10.3189/2013jog13j042.

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AbstractA new densification model, which simulates the effect of impurities on the densification of polar firn, is presented. The classical densification models of Herron and Langway (1980) and Pimienta and Barnola (Barnola and others, 1991) are modified by assuming that the activation energy for deformation is reduced by the impurities. Motivated by recent observations, the impurity effect is formulated on an empirical basis using the seasonally varying Ca2+ ion concentration. Excellent agreement between simulated and measured high-resolution density profiles confirms the new approach. The same parameterization applies for Greenland and Antarctica despite the one order of magnitude difference in impurity concentration. The new models allow us, for the first time, to simulate the density layering in firn down to the firn–ice transition. Our results emphasize the importance of impurities and density layering for the air entrapment and for dating gas records of deep ice cores, in particular for glacial climate conditions where the impurity concentrations are 10–100-fold higher than in modern firn.

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15

Wang, Xun Si, Jie Sun, Qiu Hua Nie, Shi Xun Dai, Xiang Hua Zhang, Bruno Bureau, Catherine Boussard, and Clément Conseil. "The Effects of Deoxidants on Ge-Se-Te Chalcogenide Glasses." Applied Mechanics and Materials 103 (September 2011): 458–63. http://dx.doi.org/10.4028/www.scientific.net/amm.103.458.

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In order to decrease the impurity absorption bands of Ge-Se-Te chalcogenide glasses in IR region. Three different kinds of deoxidants including Mg(magnesium), Al(aluminium) and Ca(calcium) were chosen. Properties measurements including density, Vis-NIR and infrared (IR) transmission spectra were adopted to analyze the relationship between impurity absorption bands and deoxidants. The concentrations of impurities in glass samples with different content of Mg were calculated by method of optic spectra. The results show that Mg is a better choice as deoxidant for chalcogenide glasses compared to Al and Ca. The values of main impurity concentration decrease from 4417.833 to 0 ppmw for Ge-O and from 55.236 to 0 ppmw for Si-O with increasing content of Mg, respectively. At least 200ppm Mg is needed to minimize the main absorption bands in IR region and G5 glass incorporated with 400ppm Mg has minimum concentration of impurities which means that it possesses the optimal transmission properties.

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Kalmykov, Rustam, Akhmed M. Karmokov, and Zaira Ansokova. "The Influence of Structural and Phase Changes on the Thermoelectric Properties of PbTe Doped with CdSe." Nano Hybrids and Composites 28 (February 2020): 20–25. http://dx.doi.org/10.4028/www.scientific.net/nhc.28.20.

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In this article, the influence of structural and phase changes on the thermoelectric properties of PbTe doped with CdSe compounds of various molar concentrations were studied. The research showed that with a minimum value of the lattice parameter of the formed new phases in the PbTe matrix (at an impurity concentration of 0.5 mol%), the specific electrical conductivity and thermoEMF coefficient have a minimum value. A further increase in concentration leads to an increase in these parameters.

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Arora, Manju, Rayees A. Zargar, and S. D. Khan. "EPR Spectroscopy of Different Sol Concentration Synthesized Nanocrystalline-ZnO Thin Films." International Journal of Spectroscopy 2015 (November 22, 2015): 1–7. http://dx.doi.org/10.1155/2015/431678.

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Nanocrystalline zinc oxide (nc-ZnO) thin films were grown on p-type silicon substrate through spin coating by sol-gel process using different sol concentrations (10 wt.%, 15 wt.%, and 25 wt.%). These films were characterized by high resolution nondestructive X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDS) attachment, and electron paramagnetic resonance (EPR) techniques to understand variations in structural, morphological, and oxygen vacancy with respect to sol concentration. The film surface morphology changes from nanowall to nanorods on increasing sol concentration. EPR spectra revealed the systematic variation from ferromagnetic to paramagnetic nature in these nc-ZnO films. The broad EPR resonance signal arising from the strong dipolar-dipolar interactions among impurity defects present in nc-ZnO film deposited from 10 wt.% sol has been observed and a single strong narrow resonance signal pertaining to oxygen vacancies is obtained in 25 wt.% sol derived nc-ZnO film. The concentrations of impurity defects and oxygen vacancies are evaluated from EPR spectra, necessary for efficient optoelectronic devices development.

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Peng, Yan, Xian Gang Xu, Xiao Bo Hu, Xiu Fang Chen, and Yu Qiang Gao. "A Comparative Study of the Morphologies of Etch Pits in Semi-Insulating Silicon Carbide Single Crystals." Materials Science Forum 679-680 (March 2011): 145–52. http://dx.doi.org/10.4028/www.scientific.net/msf.679-680.145.

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Contactless resistivity mapping, scanning electron microscope (SEM) and confocal laser microscope have been used to study the relationship of the resistivity and the etching behavior of the semi-insulating 6H-SiC wafer. Evidence is presented that the morphologies of the etch pits vary significantly with the impurity concentrations. The V impurity strongly affects the etch rates of edge, screw and mixed dislocations. For the dislocation containing the Burgers vector component of <0001>, its vertical etch rate is enhanced distinctly. In contrast, the horizontal etch rate becomes larger for the dislocation containing the Burgers vector component of < >. The shape of the etch pits reflects the Fermi level of the semi-insulating wafer and the net shallow impurity concentration.

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19

Новокрещенова, А. А., В. Г. Лебедев, and П. К. Галенко. "Захват примеси в разбавленном растворе: фазово-полевое моделирование затвердевания." Журнал технической физики 91, no. 5 (2021): 748. http://dx.doi.org/10.21883/jtf.2021.05.50685.324-20.

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Based on numerical simulation of the nonstationary process of directional solidification of a weak solution flat–front within locally the non–equilibrium phase–field model study of the process of redistribution of the impurity in the vicinity of the diffuse boundary between the liquid and solid phases. As a result of numerical modeling, profiles of the average impurity concentration near the interface are obtained. From the obtained profiles of the average concentration, the distribution of concentrations in the solid and liquid phases at different speeds of the front movement is determined using the phase field. The constructed graphs of the dependence of the distribution coefficient on the velocity are compared with the data for the hyperbolic model of continuous growth and previously performed calculations in the quasi–stationary approximation. The influence of the model parameters on the type of dependence of the distribution coefficient on the front velocity and on the distribution profile of the concentration inside the diffuse interface is studied.

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Новокрещенова, А. А., В. Г. Лебедев, and П. К. Галенко. "Захват примеси в разбавленном растворе: фазово-полевое моделирование затвердевания." Журнал технической физики 91, no. 5 (2021): 748. http://dx.doi.org/10.21883/jtf.2021.05.50685.324-20.

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Based on numerical simulation of the nonstationary process of directional solidification of a weak solution flat–front within locally the non–equilibrium phase–field model study of the process of redistribution of the impurity in the vicinity of the diffuse boundary between the liquid and solid phases. As a result of numerical modeling, profiles of the average impurity concentration near the interface are obtained. From the obtained profiles of the average concentration, the distribution of concentrations in the solid and liquid phases at different speeds of the front movement is determined using the phase field. The constructed graphs of the dependence of the distribution coefficient on the velocity are compared with the data for the hyperbolic model of continuous growth and previously performed calculations in the quasi–stationary approximation. The influence of the model parameters on the type of dependence of the distribution coefficient on the front velocity and on the distribution profile of the concentration inside the diffuse interface is studied.

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21

Krayovskyy, Volodymyr, Volodymyr Pashkevych, Mariya Rokomanyuk, Petro Haranuk, Volodymyr Romaka, Yuriy Stadnyk, Lyubov Romaka, and Andriy Horyn. "KINETIC AND ENERGETIC PERFORMANCES OF THERMOMETRIC MATERIAL TiCo1-xMnxSb: MODELLING AND EXPERIMENT." Measuring Equipment and Metrology 82, no. 1 (2021): 19–25. http://dx.doi.org/10.23939/istcmtm2021.01.019.

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The results of a complex study of the semiconductor thermometric material TiСo1-xMnxSb, х=0.01–0.10, for the producing of sensitive elements of thermoelectric and electro resistive sensors are presented. Microprobe analysis of the concentration of atoms on the surface of TiСo1-xMnxSb samples established their correspondence to the initial compositions of the charge, and X-ray phase analysis showed the absence of traces of extraneous phases on their diffractograms. The produced structural studies of the thermometric material TiСo1-xMnxSb allow to speak about the ordering of its crystal structure, and the substitution of Co atoms on Mn at the 4c position generate structural defects of acceptor nature. The obtained results testify to the homogeneity of the samples and their suitability for the study of electrokinetic performances and the manufacture of sensitive elements of thermocouples. Modeling of structural, electrokinetic and energetic performances of TiСo1-xMnxSb, х=0.01–0.10, for different variants of spatial arrangement of atoms is performed. To model energetic and kinetic performances, particularly the behavior of the Fermi level, the band gap, the density of states (DOS) distribution was calculated for an ordered variant of the structure in which Co atoms at position 4c are replaced by Mn atoms. Substitution of Co atoms (3d74s2) by Mn (3d54s2) generates structural defects of acceptor nature in the TiСo1-xMnxSb semiconductor (the Mn atom contains fewer 3d- electrons than Co). This, at the lowest concentrations of impurity atoms Mn, leads to the movement of the Fermi level from the conduction band to the depth of the band gap. In a semiconductor with the composition TiCo0.99Mn0.01Sb, the Fermi level is located in the middle of the band gap, indicating its maximum compensation when the concentrations of ionized acceptors and donors are close. At higher concentrations of impurity Mn atoms, the number of generated acceptors will exceed the concentration of donors, and the concentration of free holes will exceed the concentration of electrons. Under these conditions, the Fermi level approach, and then the level of the valence band TiСo1-xMnxSb cross: the dielectric-metal conductivity transition take place. The presence of a high-temperature activation region on the temperature dependence of the resistivity ln(ρ(1/T)) TiСo1‑xMnxSb at the lowest concentration of impurity atoms Mn, х=001, indicates the location of the Fermi level in the band gap of the semiconductor thermopower coefficient α(Т,х) at these temperatures specify its position - at a distance of ~ 6 meV from the level of the conduction band . In this case, electrons are the main carriers of current. The absence of a low-temperature activation region on this dependence indicates the absence of the jumping mechanism conductivity. Negative values of the thermopower coefficient α(Т,х) TiСo0,99Mn0,01Sb at all temperatures, when according to DOS calculations the concentrations of acceptors and donors are close, and the semiconductor is maximally compensated, can be explained by the higher concentration of uncontrolled donors. However, even at higher concentrations of impurity Mn atoms in TiСo0,98Mn0,02Sb, the sign of the thermopower coefficient α(Т,х) remains negative, but the value of resistivity ρ(х,Т) increases rapidly, and the Fermi level deepens into the forbidden zone at a distance of ~ 30 meV. The rapid increase in the values of the resistivity ρ(х,Т) in the region of concentrations х=0.01–0.02 shows that acceptors are generated in the TiСo1-xMnxSb semiconductor when Co atoms are replaced by Mn, which capture free electrons, reducing their concentration. However, negative values of the thermopower coefficient α(Т,х) are evidence that either the semiconductor has a significant concentration of donors, which is greater than the number of introduced acceptors (х=0.02), or the crystal simultaneously generates defects of acceptor and donor nature. The obtained result does not agree with the calculations of the electronic structure of the TiСo1-xMnxSb semiconductor. It is concluded that more complex structural changes occur in the semiconductor than the linear substitution of Co atoms by Mn, which simultaneously generate structural defects of acceptor and donor nature by different mechanisms, but the concentration of donors exceeds the concentration of generated acceptors. Based on a comprehensive study of the electronic structure, kinetic and energetic performances of the thermosensitive material TiСo1-xMnxSb, it is shown that the introduction of impurity Mn atoms into TiCoSb can simultaneously generate in the semiconductor an acceptor zone (substitution of Co atoms for Mn) and donor zones and of different nature. The ratio of the concentrations of ionized acceptors and donors generated in TiСo1-xMnxSb will determine the position of the Fermi level and the mechanisms of electrical conductivity. However, this issue requires additional research, in particular structural and modeling of the electronic structure of a semiconductor solid solution under different conditions of entry into the structure of impurity Mn atoms. The investigated solid solution TiСo1-xMnxSb is a promising thermometric material.

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Wang, Xiao Jing, and Yun Zhang. "The Effects of the Carrier Concentrations on the Hall Mobilities of ZnO:Al Thin Films Deposited by Magnetron Sputtering." Key Engineering Materials 727 (January 2017): 938–41. http://dx.doi.org/10.4028/www.scientific.net/kem.727.938.

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ZnO:Al thin films were deposited on flexible substrates by magnetron sputtering. The effects of the carrier concentrations on the hall mobilities of AZO films were investigated. When the carrier concentration was high (~1020/cm3), the hall mobility decreased with increase of the carrier concentration, showing obvious characteristics of ionized impurity scattering; moreover, the carrier mobility could be expressed to be-2.14/3 proportional of the carrier concentration by combining the results of simulation and experiments.simulation and experiment. When the carrier concentration was about a magnitude of 1019 cm-3, the carrier mobility is influenced by the carrier concentration and grain size, which means the carrier mobility was affected by both the grain boundary scattering and ionized purity scattering mechanism.

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23

Custer, J. S., Michael O. Thompson, D. J. Eaglesham, D. C. Jacobson, and J. M. Poate. "Epitaxial growth versus nucleation in amorphous Si doped with Cu and Ag." Journal of Materials Research 8, no. 4 (April 1993): 820–29. http://dx.doi.org/10.1557/jmr.1993.0820.

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The competition between solid phase epitaxy and random nucleation in amorphous Si implanted with Cu and Ag has been studied. At low metal concentrations, solid phase epitaxy proceeds with slight deviations from the intrinsic rate, with the impurity segregated and evenly distributed in the amorphous layer. At an impurity concentration of 0.12 at.%, rapid nucleation occurs, transforming the remaining layer into polycrystalline Si. The nucleation rate is ≥108 the intrinsic homogeneous rate. The effects of the metals on epitaxy scale with the amount of metal–Si interaction. Nucleation appears to occur when the metal impurities exceed their absolute solubility limit and begin to phase separate.

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Ergashov, Yokub, Boltaxodja Umirzakov, Nebodir Nurmatov, and Golib Otamurodov. "Experimental and theoretical study of the effect of bombardment with Ar+ ions on the spectrum of valence electrons of a Si (111) single crystal." E3S Web of Conferences 288 (2021): 01013. http://dx.doi.org/10.1051/e3sconf/202128801013.

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The paper studies the effect of disordering of the surface layers on the electronic and optical properties of single-crystal silicon.An analysis of the photoelectron spectra shows that with complete amorphization of the surface density, the condition of Si valence electrons of changes significantly. In particular, the positions of the main maximum of the electrons of the valence band of Si (111) shift by ~ 0.4 eV towards higher binding energies and the band gap Eg increases by 0.1-0.15 eV. The energy of a valence electron in amorphized silicon, which at low impurity concentrations, i.e. at low bombardment doses (D <1015 cm–2), the potential Mkk and, therefore, the shift of the maximum of the density of states vary linearly with respect to concentration. At high impurity concentrations (at doses D> 1015 cm–2), corresponding to the transition to amorphous silicon, the concentration dependence of Mkk is very weak. Therefore, upon amorphization, the peak A of the density of states of the silicon valence band under consideration is shifted to the region of lower electron binding energies. The theoretical substantiation of the obtained experimental results is given.

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25

Martinuzzi, Santo, and Olivier Palais. "Impurity Concentration Mapping in Mulitcrystalline Silicon Wafers." Solid State Phenomena 78-79 (April 2001): 3–10. http://dx.doi.org/10.4028/www.scientific.net/ssp.78-79.3.

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Tenne, R., H. Mariette, C. Levy-Clement, and R. Jäger-Waldau. "Control of impurity concentration on CdSe surfaces." Journal of Crystal Growth 86, no. 1-4 (January 1988): 826–33. http://dx.doi.org/10.1016/0022-0248(90)90811-x.

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27

Gunko, Irina. "Optical sensor of harmful air impurity concentration." PRZEGLĄD ELEKTROTECHNICZNY 1, no. 7 (July 2, 2021): 78–81. http://dx.doi.org/10.15199/48.2021.07.15.

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28

Gonik, Michael A., and Florin Baltaretu. "Problem of attaining constant impurity concentration over ingot height." Modern Electronic Materials 4, no. 2 (June 1, 2018): 41–51. http://dx.doi.org/10.3897/j.moem.4.2.38536.

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The possibility of growing crystals with homogeneous impurity distribution over crystal height has been demonstrated in a study of segregation during silicon and germanium growth from thin melt layers using the submerged heater method. Numeric simulation of 200 mm diam. antimony-doped germanium crystallization has shown that, beginning from a 40 mm melt layer thickness, the exact problem solution with convection allowance is identical to the unidimensional heat exchange problem solution in the central ingot part. The conditions under which convection can be ignored in mass transport calculation are more rigorous: the melt layer height must be within 20 mm. In this case Tiller’s ratio can be used for calculating the longitudinal impurity distribution for predominantly diffusion-controlled mass transport pattern. Analysis of the existing attempts to describe the experimental crystal growth results using the simplified formulae shows that they only yield acceptable results if the actual growth rate or change in melt layer thickness during crystallization are taken into account, e.g. as in the formula suggested by Marchenko et al. One can therefore analytically describe the longitudinal impurity distribution in the ingot, e.g. B and P distribution in silicon, and recommend the degree of additional doping of the melt zone under the heater so that to provide a constant impurity concentration over the ingot height. Homogeneous material can be obtained after residual layer solidification in the end portion of the ingot if the growth rate is controlled through varying the cooling rate.

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Agarwal, Shiv Kumar, Upendra Bhatnagar, and Navin Rajesh. "Acute and Genotoxic Profile of a Dimeric Impurity of Cefotaxime." International Journal of Toxicology 23, no. 1 (January 2004): 41–45. http://dx.doi.org/10.1080/10915810490265441.

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The manufacturing and storage of cefotaxime produces different impurities of various concentrations, which may influence the efficacy and safety of the drugs. Because no report of toxicity data is available on the impurities of cefotaxime, the present acute and genotoxicity studies were designed and conducted to provide the information for establishing the safety profile and qualification of the dimeric impurity. Histidine-requiring mutants of Salmonella typhimurium TA97a, TA98, TA100, TA102, and TA1535 strains, with or without metabolic activation (S-9), were used for point-mutation tests. Neither increase in numbers of revertants, indicative of mutagenic activity, nor inhibition of bacterial growth, indicative of cytotoxicity, was observed when the dimeric impurity of cefotaxime at concentrations of 0.62, 1.85, 5.56, 16.67, and 50 μg/plate was incorporated into plates containing S. typhimurium bacterial strains. Cultures of Chinese hamster ovary (CHO) cells at a cell density of 2 × 105 cells per culture were exposed to the dimeric impurity of cefotaxime at the concentration of 11.25, 22.5, and 45 mg per culture, with or without metabolic activation, and harvested at 18 h after exposure. No chromosomal aberrations in the cultured mammalian cells were recorded. Acute intramuscular administration of the dimeric impurity of cefotaxime in Sprague-Dawley rats did not result in any clinical signs and gross pathological changes up to 2000 mg/kg-body weight. The results of these studies indicated that the dimeric impurity of cefotaxime is nonmutagenic in Ames test, nonclastogenic in vitro, and acutely nontoxic in rats.

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Денисюк, И. Ю., Е. Н. Галашева, М. В. Успенская, and М. И. Фокина. "Спектральные зависимости оптического поглощения иммобилизованного в пленке Родамина Б от концентрации ионов меди в воде." Журнал технической физики 128, no. 11 (2020): 1784. http://dx.doi.org/10.21883/os.2020.11.50185.140-20.

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The influence of copper ion concentration on the absorption spectrum of Rhodamine B in molecular form in an alcohol solution and immobilized in a polymer hydrogel film was studied. The sensitivity of the system to the presence of copper ions at a concentration of 0.1 mg/l, sufficient for practical use, is shown. The insolubility of Rhodamine B in water when it is immobilized in the volume of a photopolymerizing hydrogel film makes it possible to create a chemosensor that is stable at long exposures and can sense ultra-small concentrations of the analyzed impurity.

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Симаков, Н. Н. "Расчет межфазного массообмена в факеле распыла форсунки с учетом кризиса." Журнал технической физики 90, no. 4 (2020): 560. http://dx.doi.org/10.21883/jtf.2020.04.49077.2566.

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A numerical model and the results of calculation of the interfacial mass transfer in a two-phase flow formed by spraying a liquid in a gas with a nozzle are described. The basis of the proposed mathematical model is the differential equations of the nonstationary flow of a compressible medium supplemented by the equation of mass transfer from a gas to droplets. Going over to the difference analogues of the equations of continuity and phase motion, we used the well-known explicit Lax-Vendroff scheme. Herein, the axial profiles of the velocities of droplets and gas, concentrations of gas impurity in a free spray flow, as well as radial profiles of impurity concentrations in a two-phase flow through a cylindrical apparatus are calculated and presented accounting the early drag crisis of droplets, the mass-transfer crisis and the turbulent friction characteristics in gas discovered in previous experiments. Calculations show dependences of the volumetric gas flow, concentration of the gas admixture at the apparatus output, and the amount of impurity absorbed by a liquid on the height and cross-section area of the apparatus.

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Alexander, Jude S., Geoffrey W. R. Edwards, Blair P. Bromley, and Keira Lane. "THE EFFECTS OF TYPICAL THORIUM IMPURITIES ON THORIUM-BASED NUCLEAR FUELS." CNL Nuclear Review 9, no. 1 (December 1, 2020): 27–38. http://dx.doi.org/10.12943/cnr.2018.00002.

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Natural thorium contains impurities of numerous isotopes. A study was performed to examine the influence of naturally occurring impurities in thorium-based fuels on a few parameters of interest such as: exit burnup, coolant void reactivity (CVR), fuel temperature coefficients (FTC), and the radiotoxicity of the used fuel. Two different fuel bundle designs were modeled: a 43-element bundle containing 2.25% U-233, and a 35-element bundle containing 1.45% U-233. Naturally occurring thorium fuel impurities were applied to both fuel bundle models at various concentrations, from 0% to 100% of the expected maximum. For burnup-averaged k-infinity (k∞) values of 1.050 and 1.030, exit burnup, burnup-weighted CVR, and burnup-weighted FTC were calculated using the neutron transport code WIMS-AECL, and plotted against fraction of full impurity concentration to determine how the impurity levels affect these reactor physics parameters of interest. For the most-realistic (for CANDU) burnup-averaged k∞ of 1.050, both the inhalation radiotoxicity and the production of U-232 were calculated using the fuel depletion code WOBI. Up to the maximum impurity concentrations considered, no effects on the investigated fuel performance parameters were found to be greater than a few percent.

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Grimm, Robert E., David E. Stillman, and Joseph A. MacGregor. "Dielectric signatures and evolution of glacier ice." Journal of Glaciology 61, no. 230 (2015): 1159–70. http://dx.doi.org/10.3189/2015jog15j113.

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AbstractWe analyzed the dielectric spectra (0.1 Hz–1 MHz) of 49 firn and ice samples from ice sheets and glaciers to better understand how differing ice formation and evolution affect electrical properties. The dielectric relaxation of ice is well known and its characteristic frequency increases with the concentration of soluble impurities in the ice lattice. We found that meteoric ice and firn generally possess two such relaxations, indicating distinct crystal populations or zonation. Typically, one population is consistent with that of relatively pure ice, and the other is significantly more impure. However, high temperatures (e.g. temperate ice), long residence times (e.g. ancient ice from Mullins Glacier, Antarctica) or anomalously high impurity concentrations favor the development of a single relaxation. These relationships suggest that annealing causes two dielectrically distinct populations to merge into one population. The dielectric response of temperate ice samples indicates increasing purity with increasing depth, suggesting ongoing rejection of impurities from the lattice. Separately, subglacially (lake) frozen samples from the Vostok (Antarctica) 5G ice core possess a single relaxation whose variable characteristic frequency likely reflects the composition of the source water. We conclude that multi-frequency methods are essential to dielectric discrimination between different types of glacier ice.

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Benzaquen, R., T. Erland, C. Lacelle, E. Fortin, and A. P. Roth. "Photoluminescence of heavily doped GaAs and Ga0.85In0.15As." Canadian Journal of Physics 69, no. 3-4 (March 1, 1991): 339–45. http://dx.doi.org/10.1139/p91-057.

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Zinc-doped, p-type, GaAs and Ga0.85In0.15As samples with a carrier concentration up to p = 1.95 × 1020 cm−3 were studied by low-temperature photoluminescence. At low doping levels, recombinations involving impurity states provide a measurement of the zinc-acceptor binding energy in the Ga0.85In0.15As alloy. At high concentrations, the discrete acceptor levels are replaced by an impurity band. In the presence of a high density of impurities, potential fluctuations and interparticle interactions result in a band-gap renormalization that is observed with photoluminescence experiments. This phenomenon is analyzed on the basis of available models that take into account the nonconservation of momentum for optical transitions as well as many-body effects.

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35

Collado, H. P. Ojeda, Gonzalo Usaj, and C. A. Balseiro. "Impurity states and Localization in Bilayer Graphene: the Low Impurity Concentration Regime." Journal of Physics: Conference Series 568, no. 5 (December 8, 2014): 052003. http://dx.doi.org/10.1088/1742-6596/568/5/052003.

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36

Schipper, C. Ian, William D. A. Rickard, Steven M. Reddy, David W. Saxey, Jonathan M. Castro, Denis Fougerouse, Zakaria Quadir, Chris Conway, David J. Prior, and Kat Lilly. "Volcanic SiO2-cristobalite: A natural product of chemical vapor deposition." American Mineralogist 105, no. 4 (April 1, 2020): 510–24. http://dx.doi.org/10.2138/am-2020-7236.

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Abstract Cristobalite is a low-pressure, high-temperature SiO2 polymorph that occurs as a metastable phase in many geologic settings, including as crystals deposited from vapor within the pores of volcanic rocks. Such vapor-phase cristobalite (VPC) has been inferred to result from silica redistribution by acidic volcanic gases but a precise mechanism for its formation has not been established. We address this by investigating the composition and structure of VPC deposited on plagioclase substrates within a rhyolite lava flow, at the micrometer to nanometer scale. The VPC contains impurities of the form [AlO4/Na+]0—coupled substitution of Al3+ charge-balanced by interstitial Na+—which are typical of cristobalite. However, new electron probe microanalysis (EPMA) element maps show individual crystals to have impurity concentrations that systematically decline from crystal cores-to-rims, and atom probe tomography reveals localized segregation of impurities to dislocations. Impurity concentrations are inversely correlated with degrees of crystallinity [observed by electron backscatter diffraction (EBSD), hyperspectral cathodoluminescence, laser Raman, and transmission electron microscopy (TEM)], such that crystal cores are poorly crystalline and rims are highly ordered tetragonal α-cristobalite. The VPC-plagioclase interfaces show evidence that dissolution-reprecipitation reactions between acidic gases and plagioclase crystals yield precursory amorphous SiO2 coatings that are suitable substrates for initial deposition of impure cristobalite. Successive layers of cubic β-cristobalite are deposited with impurity concentrations that decline as Al-bearing gases rapidly become unstable in the vapor cooling within pores. Final cooling to ambient temperature causes a displacive transformation from β→α cristobalite, but with locally expanded unit cells where impurities are abundant. We interpret this mechanism of VPC deposition to be a natural proxy for dopant-modulated Chemical Vapor Deposition, where halogen-rich acidic gases uptake silica, react with plagioclase surfaces to form suitable substrates and then deposit SiO2 as impure cristobalite. Our results have implications for volcanic hazards, as it has been established that the toxicity of crystalline silica is positively correlated with its purity. Furthermore, we note that VPC commonly goes unreported, but has been observed in silicic lavas of virtually all compositions and eruptive settings. We therefore suggest that despite being metastable at Earth's surface, cristobalite may be the most widely occurring SiO2 polymorph in extrusive volcanic rocks and a useful indicator of gas-solid reaction having occurred in cooling magma bodies.

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37

MORADIAN, ROSTAM, and ALI FATHALIAN. "MAGNETIC IMPURITY EFFECTS IN ZIGZAG CARBON NANOTUBES." International Journal of Nanoscience 06, no. 06 (December 2007): 453–59. http://dx.doi.org/10.1142/s0219581x07005036.

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We investigate effects of magnetic impurity doping on the Curie critical temperature (Tc) of semiconducting carbon nanotubes. Variation of Tc as a function of impurity concentration for different coupling constant (J), and spin value (S) are calculated. We found by increasing J and S, the critical temperature is increased. Also we calculated Tc in terms of band filling for different impurity concentration, exchange coupling and impurity spin magnitude.

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38

UNGAN, F., U. YESILGUL, E. KASAPOGLU, H. SARI, and I. SOKMEN. "OPTICAL INTERSUBBAND TRANSITIONS AND BINDING ENERGIES OF DONOR IMPURITIES IN Ga1-xInxNyAs1-y/GaAs/Al0.3Ga0.7As QUANTUM WELL UNDER THE ELECTRIC FIELD." International Journal of Modern Physics B 26, no. 06 (March 10, 2012): 1250013. http://dx.doi.org/10.1142/s0217979212500130.

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The effects of nitrogen and indium mole concentration on the intersubband optical absorption for (1–2) transition and the binding energy of the shallow-donor impurities in a Ga 1-x In x N y As 1-y/ GaAs / Al 0.3 Ga 0.7 As quantum well under the electric field is theoretically calculated within the framework of the effective-mass approximation. Results are obtained for several concentrations of nitrogen and indium, and the applied electric field. The numerical results show that the intersubband transitions and the impurity binding energy strongly depend on the nitrogen and indium concentrations.

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39

Salleh, Faiz, and Hiroya Ikeda. "Influence of Impurity Band on Seebeck Coefficient in Heavily-Doped Si." Advanced Materials Research 222 (April 2011): 197–200. http://dx.doi.org/10.4028/www.scientific.net/amr.222.197.

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We calculated the Seebeck coefficient of heavily-doped Si based on theoretical models of impurity-band formation, ionization-energy shift and conduction-band tailing. The impurity band was described by using two kinds of band-width definitions and it was found that the calculated Seebeck coefficient strongly depended on the impurity-band definition. In the high impurity-concentration region, the Seebeck coefficient decreased with increasing impurity concentration, and with a peak around 1×1019 cm-3. This result was qualitatively in good agreement with the experimental result, while there was quantitative disagreement between them.

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40

Poklonski, Nikolai A., Sergey A. Vyrko, and Aliaksandr N. Dzeraviaha. "Thermal ionization energy of hydrogen-like impurities in semiconductor materials." Journal of the Belarusian State University. Physics, no. 2 (June 4, 2020): 28–41. http://dx.doi.org/10.33581/2520-2243-2020-2-28-41.

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In the work the dependence of the thermal ionization energy of hydrogen-like donors and acceptors on their concentration in n- and p-type semiconductors is analyzed analytically and numerically. The impurity concentrations and temperatures at which the semiconductors are on the insulator side of the concentration insulator – metal phase transition (Mott transition) are considered. It is assumed that impurities in the crystal are distributed randomly (according to Poisson), and their energy levels are distributed normally (according to Gauss). In the quasi-classical approximation, it is shown, for the first time, that the decrease in the ionization energy of impurities mainly occurs due to the joint manifestation of two reasons. Firstly, from the excited states of electrically neutral impurities, a quasicontinuous band of allowed energy values is formed for c-band electrons in an n-type crystal (or for v-band holes in a p-type crystal). This reduces the energy required for the thermally activated transition of electron from the donor to the c-band (for the transition of the hole from the acceptor to the v-band). Secondly, from the ground (unexcited) states of impurities a classical impurity band is formed, the width of which at low temperatures is determined only by the concentration of impurity ions. In moderately compensated semiconductors (when the ratio of the concentration of minority impurities to the concentration of majority impurities is less than 50 %) the Fermi level is located closer to the edge of the band of allowed energy values than the middle of the impurity band, that issue reduces thermal ionization energy of impurities from states in the vicinity of the Fermi level (transition of electron from a donor to the c-band, or hole from an acceptor to the v-band). Previously, these two causes of decrease in the thermal ionization energy due to increase in the concentration of impurities were considered separately. The results of calculations according to the proposed formulas are quantitatively agree with the known experimental data for a number of semiconductor materials (germanium, silicon, diamond, gallium arsenide and phosphide, silicon carbide, zinc selenide) with a moderate compensation ratio.

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41

Звонарев, С. В., and Н. О. Смирнов. "Тушение люминесценции в керамиках оксида алюминия допированных магнием." Физика твердого тела 61, no. 5 (2019): 934. http://dx.doi.org/10.21883/ftt.2019.05.47596.36f.

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AbstractThe effect of magnesium impurity on luminescent properties of alumina ceramics sintered at high temperatures under vacuum is studied by pulsed cathodoluminescence, photoluminescence, and thermoluminescence. At dopant concentrations >1 wt %, high-temperature synthesis results in formation of defects associated with magnesium, which were identified in the pulsed cathodoluminescence (520 nm) and photoluminescence (767 nm) spectra, as well as in the thermoluminescence curves (380 K). It is found that increased magnesium concentration leads to luminescence quenching of the intrinsic centers ( F centers) of alumina in the PCL emission band at 400 nm, impurity defects (Mn^4+ and Cr^3+) in the photoluminescence emission bands at 673 and 689 nm, and all the recorded thermoluminescence peaks at 380, 450, and 615 K.

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42

Lee, Jong Hoon, Min Cheol Chu, Seong Jai Cho, and Duk Yong Yoon. "Normal and Abnormal Grain Growth in Ceramics - NbC-Co and Alumina." Advanced Materials Research 11-12 (February 2006): 47–52. http://dx.doi.org/10.4028/www.scientific.net/amr.11-12.47.

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Normal and abnormal grain growth has been observed in 70NbC-30Co with varying B concentrations at 1450°C and in alumina with varying impurity and additive concentrations at 1600°C -1650°C as typical systems with and without liquid matrix. The grain growth behavior depends on the roughening of the interfaces as indicated by the grain and grain boundary shapes. When 4% B is added to 70NbC-30Co, the NbC grains in Co-rich liquid matrix are spherical and undergo diffusion controlled normal growth, because the grain-liquid interface is rough. As the B concentration is decreased to 3, 2, 1, and 0%, the NbC grains become more cubic and the tendency for abnormal grain growth increases because of the step growth mechanism of the flat singular surface segments. When compacts of high purity alumina powder are sintered at 1650°C, the grain boundaries are smoothly curved, indicating their atomically rough structures. With increasing impurity content—in particular SiO2—in the alumina powder, abnormal grain growth becomes more pronounced with increasing number of flat grain boundaries. These singular grain boundaries are expected to move by a step mechanism and thus cause the abnormal grain growth. These results show that the interface roughening and hence the grain growth mode changes gradually with the additive or impurity concentrations. Therefore, the abnormal grain growth cannot be sharply distinguished from the normal grain growth as has been previously suggested in general and for alumina in particular.

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43

Zhang, Aiwu, Yichen Li, Craig Thorn, Carl Bromberg, Milind V. Diwan, Steve Kettell, Vittorio Paolone, et al. "Modeling impurity concentrations in liquid argon detectors." Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 1010 (September 2021): 165491. http://dx.doi.org/10.1016/j.nima.2021.165491.

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44

YAMAMURA, Hidemasa, Shinichiro KASHIHARA, Yukio WATANABE, Eigo TADA, Katsuaki FUKUSADA, Toshimasa SHIMODA, Kaoru MASUDA, Mamoru AOKI, and Syuichiro SUDA. "Measurements of Impurity Concentration for a Helium Compressor." TEION KOGAKU (Journal of Cryogenics and Superconductivity Society of Japan) 29, no. 1 (1994): 28–33. http://dx.doi.org/10.2221/jcsj.29.28.

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45

Suzuki, Kunihiro, and Ritsuo Sudo. "Analytical expression for ion-implanted impurity concentration profiles." Solid-State Electronics 44, no. 12 (December 2000): 2253–57. http://dx.doi.org/10.1016/s0038-1101(00)00219-7.

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46

Bahn, Chi Bum, Si Hyoung Oh, Byung Gi Park, Il Soon Hwang, In Hyoung Rhee, Uh Chul Kim, and Jung Won Na. "Impurity concentration behaviors in a boiling tubesheet crevice." Nuclear Engineering and Design 225, no. 2-3 (November 2003): 129–44. http://dx.doi.org/10.1016/s0029-5493(03)00179-1.

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Bahn, Chi Bum, Si Hyoung Oh, Byung Gi Park, Il Soon Hwang, In Hyoung Rhee, Uh Chul Kim, and Jung Won Na. "Impurity concentration behaviors in a boiling tubesheet crevice." Nuclear Engineering and Design 225, no. 2-3 (November 2003): 145–57. http://dx.doi.org/10.1016/s0029-5493(03)00180-8.

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Stepanov, V. M., O. V. Bilevich, and A. N. Kolesnikov. "Total impurity concentration in high-purity simple substances." Inorganic Materials 42, no. 11 (November 2006): 1193–97. http://dx.doi.org/10.1134/s0020168506110045.

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Tang, Zhengmin, Hu Deng, Quancheng Liu, Jin Guo, and Liping Shang. "Quantitative analysis of low-concentration α-HMX based on terahertz spectroscopy." Analytical Methods 12, no. 47 (2020): 5684–90. http://dx.doi.org/10.1039/d0ay01583k.

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Pezoldt, Jörg, V. S. Kharlamov, Dmitri V. Kulikov, Maxim N. Lubov, and Yuri V. Trushin. "Concentration Profile Simulation of SiC/Si Heterostructures." Materials Science Forum 858 (May 2016): 501–4. http://dx.doi.org/10.4028/www.scientific.net/msf.858.501.

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Computer simulation of the concentration profiles evolution in SiC/Si heterostructures during growth and subsequent ion sputtering is presented. Simulation is based on a complex self-consistent approach combining kinetic and ballistic methods. Within the framework of the proposed method concentration depth profiles in SiC/Si heterostructure with pre-deposited Ge impurity are calculated and compared with experimental sputtering profiles obtained by secondary ion mass spectrometry.

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Journal articles on the topic 'Concentration impurete'

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