"Etchability" of ion tracks in Si02/Si and Si3N4/Si thin layers

We have calculated radii and lifetime of the molten regions or the regions heated to the melting point that are formed under irradiation of amorphous SiO2 and Si3N4 with swift ions. A computer simulation was carried out on the base of thermal spike model. A comparison of calculated track parameters with ion track etching data have been made for these materials. It is shown that an existence of molten region along swift ion trajectory may be a criterion for a track “etchability” in the case of SiO2. In the same conditions of chemical etching diameter of etched tracks in SiO2 is proportional to the radius and lifetime of the molten region. This information is important for a correct choice of irradiation regime aimed at preparation of nanoporous layers with high pore density ( 10 10 cm-2). When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2087

"Etchability" of ion tracks in Si02/Si and Si3N4/Si thin layers

We have calculated radii and lifetime of the molten regions or the regions heated to the melting point that are formed under irradiation of amorphous SiO2 and Si3N4 with swift ions. A computer simulation was carried out on the base of thermal spike model. A comparison of calculated track parameters with ion track etching data have been made for these materials. It is shown that an existence of molten region along swift ion trajectory may be a criterion for a track “etchability” in the case of SiO2. In the same conditions of chemical etching diameter of etched tracks in SiO2 is proportional to the radius and lifetime of the molten region. This information is important for a correct choice of irradiation regime aimed at preparation of nanoporous layers with high pore density ( 10 10 cm-2). When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2087

Effect of Xe ion (167 MeV) irradiation on polycrystalline SiC implanted with Kr and Xe at room temperature

The effect of swift heavy ion (Xe 167 MeV) irradiation on polycrystalline SiC individually implanted with 360 keV Kr and Xe ions at room temperature to fluences of 2×1016 cm-2 and 1×1016 cm-2 respectively, was investigated using transmission electron microscopy (TEM), Raman spectroscopy and Rutherford backscattering spectrometry (RBS). Implanted specimens were each irradiated with 167 MeV Xe+26 ions to a fluence of 8.3×1014 cm-2 at room temperature. It was observed that implantation of 360 keV Kr and Xe ions individually at room temperature amorphized the SiC from the surface up to a depth of 186 and 219 nm respectively. Swift heavy ion (SHI) irradiation reduced the amorphous layer by about 27 nm and 30 nm for the Kr and Xe samples respectively. Interestingly, the reduction in the amorphous layer was accompanied by the appearance of randomly oriented nanocrystals in the former amorphous layers after SHI irradiation in both samples. Previously, no similar nanocrystals were observed after SHI irradiations at electron stopping powers of 33 keV/nm and 20 keV/nm to fluences below 1014 cm-2. Therefore, our results suggest a fluence threshold for the formation of nanocrystals in the initial amorphous SiC after SHI irradiation. Raman results also indicated some annealing of radiation damage after swift heavy ion irradiation and the subsequent formation of small SiC crystals in the amorphous layers. No diffusion of implanted Kr and Xe was observed after swift heavy ion irradiation.National Research Foundation (NRF)http://iopscience.iop.org0022-37272016-10-20hb201

Interface reactions between Pd thin films and SiC by thermal annealing and SHI irradiation

The solid-state reactions between Pd thin films and 6H-SiC substrates induced by thermal annealing, room temperature swift heavy ion (SHI) irradiation and high temperature SHI irradiation have been investigated by in situ and real-time Rutherford backscattering spectrometry (RBS) and Grazing incidence X-ray diffraction (GIXRD). At room temperature, no silicides were detected to have formed in the Pd/SiC samples. Two reaction growth zones were observed in the samples annealed in situ and analysed by real time RBS. The initial reaction growth region led to formation of Pd3Si or (Pd2Si+Pd4Si) as the initial phase(s) to form at a temperature of about 450 °C. Thereafter, the reaction zone did not change until a temperature of 640 °C was attained where Pd2Si was observed to form in the reaction zone. Kinetic analysis of the initial reaction indicates very fast reaction rates of about 1.55×1015 at.cm-2/s and the Pd silicide formed grew linear with time. SHI irradiation of the Pd/SiC samples was performed by 167 MeV Xe26+ ions at room temperature at high fluences of 1.07×1014 and 4×1014 ions/cm2 and at 400 °C at lower fluences of 5×1013 ions/cm2. The Pd/SiC interface was analysed by RBS and no SHI induced diffusion was observed for room temperature irradiations. The sample irradiated at 400 °C, SHI induced diffusion was observed to occur accompanied with the formation of Pd4Si, Pd9Si2 and Pd5Si phases which were identified by GIXRD analysis.http://www.elsevier.com/locate/nimb2017-03-31hb2016Physic

Surface and interface modification of Zr/SiC interface by swift heavy ion irradiation

In this study thin Zr films (135 nm) were deposited on 6H-SiC substrate at room temperature by sputter deposition. The Zr/SiC couples were irradiated by 167 MeV Xe26+ ions at room temperature at fluences of 5.0 1012, 1.0 1013, 5.0 1013, 2.0 1014, 3.1 1014 and 6.3 1014 ions/cm2. The samples were analysed before and after irradiation using Rutherford backscattering spectroscopy (RBS), atomic force microscopy (AFM) and secondary electron microscopy (SEM). The surface morphology from SEM analysis revealed a homogeneous Zr surface which did not vary with increasing fluences of irradiation. AFM analysis revealed that the Rrms surface roughness did increase from the as-deposited value of 1.6 nm and then decrease at higher SHI irradiation fluences to 1.4 nm. RBS results indicate that interface mixing between Zr and SiC interface occurred and varied linearly with irradiation ion fluence. The value obtained for diffusivity of Zr shows that the mixing was due to interdiffusion across the interface during a transient melt phase according to the thermal spike model.http://www.elsevier.com/locate/nimb2016-07-01hb201

Effect of thermal annealing on SHI irradiated indium implanted glassy carbon

Please read abstract in the article.The National Research Foundation (NRF) of South Africa and the University of Pretoria.http://www.elsevier.com/locate/nimb2022-06-22hj2022Materials Science and Metallurgical EngineeringPhysic

Structural modification of indium implanted glassy carbon by thermal annealing and SHI irradiation

Please read abstract in the article.The National Research Foundation (NRF) (grant no. 110363) of South Africahttp://www.journals.elsevier.com/vacuum2018-10-30hj2017Physic

Effects of Ag and Sr dual ions implanted into SiC

Please read abstract in the article.National Research Foundation of South Africa, Knowledge Interchange and Collaboration Programme (KIC).http://www.elsevier.com/locate/nimbhj2021Physic