我们对Mn注入的3 $C$-SiC（3 $C$-SiC：Mn）和碳掺入的Mn $_{5}$ Si $_{2}$（Mn $_{5}$ Si $_{2}$：C）进行了X射线光电子能谱（XPS）、X射线吸收谱（XAS）和共振光电子能谱（RPES）测量。3-$C$ -SiC：Mn和Mn-$_{5}$-Si-$_{2}$：C的Mn 2-$p$芯能级XPS和XAS谱相似，表现出介于局域态和巡游态之间的“中间态”行为.发现与Mn $_{5}$ Si $_{2}$：C相比，在3 $C$ -SiC：Mn中费米能级处的强度被抑制.这些观察结果是一致的形成Mn $_{5}$ Si $_{2}$：C簇在3 $C$ -SiC主机，在最近的透射电子显微镜研究中观察到。
英文摘要：
We have performed x-ray photoemission spectroscopy (XPS), x-ray absorption spectroscopy (XAS), and resonant photoemission spectroscopy (RPES) measurements of Mn-implanted 3$C$-SiC (3$C$-SiC:Mn) and carbon-incorporated Mn$_{5}$Si$_{2}$ (Mn$_{5}$Si$_{2}$:C). The Mn 2$p$ core-level XPS and XAS spectra of 3$C$-SiC:Mn and Mn$_{5}$Si$_{2}$:C were similar to each other and showed "intermediate" behaviors between the localized and itinerant Mn 3$d$ states.
The intensity at the Fermi level was found to be suppressed in 3$C$-SiC:Mn compared with Mn$_{5}$Si$_{2}$:C. These observations are consistent with the formation of Mn$_{5}$Si$_{2}$:C clusters in the 3$C$-SiC host, as observed in a recent transmission electron microscopy study.
SiC materials are potential plasma facing materials in fusion reactors. In this study, site preference and diffusion behaviors of H in pure 3C-\b{eta} SiC and in He-implanted 3C-\b{eta} SiC are investigated, on the basis of the first-principles calculations. We find that the most stable sites for H in pure 3C-\b{eta}SiC is the anti-bond site of C (ABc) in Si-C, while it becomes the bond-center (BC) site of Si-C bonds in the He-implanted 3C-\b{eta} SiC. Analysis on the electronic structures reveals that such change is attributed to the reduction of hybridization of C-Si bonds induced by He. Mor…
Thermal annealing plays a crucial role for healing the defectiveness in the ion implanted regions of DIMOSFETs (Double Implanted MOSFETs) devices. In this work, we have studied the effect of a double step annealing on the body (Al implanted) and the source (P implanted) regions of such devices. We found that a high temperature annealing (1750°C, 1h) followed by a lower temperature one (1500°C, 4h) is mandatory to achieve low defects concentration and good crystal quality in both the n- and p- type zones of the device.
In this paper we report the effect of hydrogen on the structural properties of AISI-H13 steel nitrogen-implanted samples in low oxygen partial pressure atmosphere. The samples were implanted in a high vacuum chamber by using a broad ion beam source. The H2+/N2+ ion composition of the beam was varied and the surface composition studied in situ by photoemission electron spectroscopy (XPS). The samples were also ex situ analyzed by X-ray diffraction and scanning electron microscopy (SEM), including energy-dispersive spectroscopy measurements. It was found that hydrogen has the effect of modifying…
The electrical behavior of Ni Schottky barrier formed onto heavily doped (ND>1019 cm-3) n-type phosphorous implanted silicon carbide (4H-SiC) was investigated, with a focus on the current transport mechanisms in both forward and reverse bias. The forward current-voltage characterization of Schottky diodes showed that the predominant current transport is a thermionic-field emission mechanism. On the other hand, the reverse bias characteristics could not be described by a unique mechanism. In fact, under moderate reverse bias, implantation-induced damage is responsible for the temperature increa…
In this paper, SiO2 layers deposited on 4H-SiC and subjected to different post deposition annealing (PDA) in NO and N2O were studied to identify the key factors influencing the channel mobility and threshold voltage stability in 4H-SiC MOSFETs. In particular, PDA in NO gave a higher channel mobility (55 cm2V-1s-1) than PDA in N2O (20 cm2V-1s-1), and the subthreshold behavior of the devices confirmed a lower total amount of interface states for the NO case. This latter could be also deduced from the behavior of the capacitance-voltage characteristics of 4H-SiC MOSFETs measured in gate controlle…
This work reports on the effect of high temperature annealing on the electrical properties of p-type implanted 4H-SiC. Ion implantations of Aluminium (Al) at different energies (30 - 200 keV) were carried out to achieve 300 nm thick acceptor box profiles with a concentration of about 1020 at/cm3. The implanted samples were annealed at high temperatures (1675-1825 °C). Morphological analyses of the annealed samples revealed only a slight increase of the surface roughness RMS up to 1775°C, while this increase becomes more significant at 1825°C (RMS=1.2nm). Room temperature Hall measurements resu…
Elucidating the interaction between magnetic moments and itinerant carriers is an important step to spintronic applications. Here, we investigate magnetic and transport properties in d0 ferromagnetic SiC single crystals prepared by postimplantation pulsed laser annealing. Magnetic moments are contributed by the p states of carbon atoms, but their magnetic circular dichroism is different from that in semi-insulating SiC samples. The anomalous Hall effect and negative magnetoresistance indicate the influence of d0 spin order on free carriers. The ferromagnetism is relatively weak in N-implanted …
Ion implantation is widely used as a surrogate for neutron irradiation in the investigation of radiation damage on the properties of materials. Due to the small depth of damage, micromechanical methods must be used to extract material properties. In this work, nanoindentation has been applied to ion irradiated silicon carbide to extract radiation-induced hardening. Residual stress is evaluated using HR-EBSD, AFM swelling measurements, and a novel microcantilever relaxation technique coupled with finite element modelling. Large compressive residual stresses of several GPa are found in the irrad…
The influence of implantation conditions on dopant activation in Al-implanted 4H-SiC: A MD study applying an Al potential fitted to DFT barriers
CDL for Multi-Scale Process Modeling of Semiconductor Devices and Sensors, at the Institute for Microelectronics, TU Wien（维也纳工业大学微电子研究所多尺度半导体器件与传感器工艺建模中心）；Silvaco Europe Ltd.（Silvaco欧洲有限公司）
Muonium dynamics as a probe for depth-resolved properties of 4H-SiC
PSI Center for Neutron and Muon Sciences（保罗谢尔研究所中子与缪子科学中心）；Advanced Power Semiconductor Laboratory, ETH Zurich（苏黎世联邦理工学院先进功率半导体实验室）；Department of Physics/ Centre for Materials Science and Nanotechnology, University of Oslo（奥斯陆大学物理系/材料科学与纳米技术研究中心）
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 betwee…
Using positive muons as local probes implanted at low energy enables gathering information about the material of interest with nanometer depth resolution (low energy muon spin rotation spectroscopy (LE-$μ$SR). In this work, we leverage the capabilities of LE-$μ$SR to perform an investigation of the SiO$_\text{2}$-SiC interface. Thermally oxidized samples are investigated before and after annealing in nitric oxide (NO) and argon (Ar) ambience. Thermal oxidation is found to result in structural changes both in the SiC crystal close to the interface and at the interface itself. Annealing in NO en…
The industrial realization of graphene has so far been limited by challenges related to the quality, reproducibility, and high process temperatures required to manufacture graphene on suitable substrates. We demonstrate that epitaxial graphene can be grown on transition metal treated 6H-SiC(0001) surfaces, with an onset of graphitization starting around $450-500^\circ\text{C}$. From the chemical reaction between SiC and thin films of Fe or Ru, $\text{sp}^{3}$ carbon is liberated from the SiC crystal and converted to $\text{sp}^{2}$ carbon at the surface. The quality of the graphene is demonstr…
We have performed scanning tunneling microscope (STM) and angle-resolved photoemission spectroscopy (ARPES) in Pb-deposited bilayer Graphene (BLG) on SiC(0001) substrate to investigate the dependence of the electronic structures on Pb-deposition amount. We have observed that the Pb atoms form islands by STM and the $π$ bands of the BLG shift toward the Fermi level by ARPES. This hole-doping-like energy shift is enhanced as the amount of Pb is increased, and we were able to tune the Dirac gap to the Fermi level by 4 ML deposition. Considering the band dispersion, we suggest that hole-doping-lik…
