Silicon carbide embedded in carbon nanofibres: structure and band gap determination

2014 ◽  
Vol 16 (44) ◽  
pp. 24437-24442 ◽  
Author(s):  
Anja Bonatto Minella ◽  
Darius Pohl ◽  
Christine Täschner ◽  
Rolf Erni ◽  
Raghu Ummethala ◽  
...  
2011 ◽  
Vol 679-680 ◽  
pp. 726-729 ◽  
Author(s):  
David T. Clark ◽  
Ewan P. Ramsay ◽  
A.E. Murphy ◽  
Dave A. Smith ◽  
Robin. F. Thompson ◽  
...  

The wide band-gap of Silicon Carbide (SiC) makes it a material suitable for high temperature integrated circuits [1], potentially operating up to and beyond 450°C. This paper describes the development of a 15V SiC CMOS technology developed to operate at high temperatures, n and p-channel transistor and preliminary circuit performance over temperature achieved in this technology.


2017 ◽  
Vol 268 ◽  
pp. 138-142 ◽  
Author(s):  
Alham Mohamed M. Emhemed ◽  
Noriza Ahmad Zabidi ◽  
Ahmad Nazrul Rosli

Theoretical molecular dynamic simulations based on plane-wave and pseudopotential density functional theory (DFT) calculations with CASTEP code were employed to explore the pressure influence on the properties of silicon carbide polytypes. The changes in lattice and electronic structures of 2H-, 4H-, and 6H-SiC polytypes at room temperature were investigated when pressures from 10 GPa to 200 GPa were applied. It’s found that the applied pressures didn’t cause a change in the hexagonal structure of the crystals, however the structural and electronic properties clearly affected by the compression. The dependences of volume reduction (V/Vo) and lattice parameters (a and c) on pressure were obtained successfully. The lattice parameters of the polytypes and c/a ratio showed a same trend under the compression with a clear similarity between 4H and 6H. The total energy-volume and enthalpy-pressure relations were estimated. The calculated energy gaps showed a reduction in the band gap width of 4H and 6H with the pressure increase while 2H band gap increased gradually with pressure. The tendency toward decreasing the density of state (DOS) at the conduction band edge was similar among the polytypes.


1997 ◽  
Vol 65 (3) ◽  
pp. 329-331 ◽  
Author(s):  
N. Achtziger ◽  
J. Grillenberger ◽  
W. Witthuhn
Keyword(s):  
Band Gap ◽  

2008 ◽  
Vol 600-603 ◽  
pp. 575-578 ◽  
Author(s):  
A. Miranda ◽  
A. Estrella Ramos ◽  
M. Cruz Irisson

In this work, the effects of the diameter and morphology on the electronic band structure of hydrogenated cubic silicon carbide (b-SiC) nanowires is studied by using a semiempirical sp3s* tight-binding (TB) approach applied to the supercell model, where the Si- and C-dangling bonds on the surface are passivated by hydrogen atoms. Moreover, TB results (for the bulk) are compared with density functional calculations in the local density approximation. The results show that though surface morphology modifies the band gap, the change is more systematic with the thickness variation. As expected, hydrogen saturation induces a broadening of the band gap energy because of the quantum confinement effect.


2000 ◽  
Vol 640 ◽  
Author(s):  
K. Miller ◽  
Q. Zhou ◽  
J. Chen ◽  
M. O. Manasreh ◽  
Z. C. Feng ◽  
...  

ABSTRACTOptical absorption spectra of undoped, n-type, and semi-insulating 6H and 4H bulk silicon carbide (SiC) were obtained in the spectral region of 200 – 3200 nm (6.20 – 0.3875 eV). Several features were observed in the absorption spectra collected for various samples. A sharp peak below the band gap was observed in 4H SiC. The intensity of this peak was observed to increase in samples that exhibit larger absorption due to free carriers, which leads us to conclude that the defect responsible for this peak is also the source of the free carriers in the materials. Additionally, a series of optical absorption peaks separated by approximately 21 meV were observed around 0.9185 eV (1350 nm). These peaks are zero phonon lines of intraband transitions in the VSi 3d shell. The optical absorption near the band edge was observed to be sample dependent. The variation of the band gap as a function of temperature is also observed to be sample dependent.


Author(s):  
Д.Д. Авров ◽  
А.Н. Горляк ◽  
А.О. Лебедев ◽  
В.В. Лучинин ◽  
А.В. Марков ◽  
...  

In this paper, we propose a model for the quantitative analysis of the dependence of the dielectric function of hexagonal silicon carbide polytypes on the photon energy in the range 0.0–6.5 eV. This model consists of the sum of two Tauc-Lorentz oscillators (main and minor) with a total band gap. This approach is used to describe the three hexagonal polytypes of silicon carbide 4H, 15R, 6H obtained in one growth process. Both C-faces and Si-faces of each polytype are analyzed. A number of conclusions have been made about the dependence of the oscillator parameters on the polytype hexagonality degree and the type of surface face. The strongest dependence is an increase of the minor oscillator amplitude with an increase of polytype hexagonality degree. It should also be noted that the band gap increases upon transition from the C-face (0001 ̅) to the Si-face (0001).


2016 ◽  
Vol 144 ◽  
pp. 551-558 ◽  
Author(s):  
J. López-Vidrier ◽  
P. Löper ◽  
M. Schnabel ◽  
S. Hernández ◽  
M. Canino ◽  
...  

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