Microstructure and properties of laser cladding FeCrBSi composite powder coatings with higher Cr content
ZnO-Bi2O3-based varistor ceramics prepared by direct high-energy ball milling of the dopants
The microstructure and electrical properties of ZnO-Bi2O3-based varistor ceramics prepared by direct high-energy ball milling of the dopants were studied. The varistor ceramics samples were characterized by XRD and SEM analysis, as well as by dc electrical measurements, such as the nonlinearity coefficients, leakage current and threshold voltage. T...
Microstructure and electrical properties of Y(NO3)3·6H2O-doped ZnO-Bi2O3-based varistor ceramics
Y(NO3)3·6H2O-doped ZnO-Bi2O3-based varistor ceramics were prepared using a solid reaction route. The microstructure, electrical properties, degradation coefficient(DV), and dielectric characteristics of varistor ceramics were studied in this paper. With increasing amounts of Y(NO3)3·6H2O in the starting composition, Y-containing Bi-rich, Y2O3, and ...
Effect of gas pressure on the properties of silicon thin film
A series of transition films from amorphous to microcrystalline silicon was successfully prepared by very high frequency plasma enhanced chemical vapor deposition(VHF-PECVD).Effects of gas pressure on the microstructure, photoelectric and transport properties of the films were investigated.The results indicate that increase of gas pressure improve ...
In-plane optical anisotropy in GaAsN/GaAs single-quantum well investigated by reflectance-difference spectroscopy
The interface properties of GaNxAs1-x/GaAs single-quantum well is investigated at 80 K by reflectance difference spectroscopy. Strong in-plane optical anisotropies (IPOA) are observed. Numerical calculations based on a 4 band K . P Hamiltonian are performed to analyze the origin of the optical anisotropy. It is found that the IPOA can be mainly att...
Interface of wet oxidized AlGaAs/GaAs distributed Bragg reflectors
The interface of wet oxidized Al0.97Ga0.03As/GaAs in a distributed Bragg reflector (DBR) structure has been studied by means of transmission electron microscopy and Raman spectroscopy. With the extension of oxidation time, the oxide/GaAs interfaces are not abrupt any more. There is an amorphous film near the oxide/GaAs interface, which is Ga2O3 rel...
Nanostructure in the p-layer and its impacts on amorphous silicon solar cells
The open circuit voltage (V-oc) of n-i-p type hydrogenated amorphous silicon (a-Si:H) solar cells has been examined by means of experimental and numerical modeling. The i- and p-layer limitations on V-oc are separated and the emphasis is to identify the impact of different kinds of p-layers. Hydrogenated protocrystalline, nanocrystalline and microc...
Silicon thin films prepared in the transition region and their use in solar cells
Diphasic silicon films (nc-Si/a-Si:H) have been prepared by a new regime of plasma enhanced chemical vapour deposition in the region adjacent of phase transition from amorphous to microcrystalline state. Comparing to the conventional amorphous silicon (a-Si:H), the nc-Si/a-Si:H has higher photoconductivity (sigma(ph)), better stability, and a broad...
Preparation and characterization of the stable nc-Si/a-Si : H films
High-quality nc-Si/a-Si:H diphasic films with improved stability were prepared by using the plasma-enhanced chemical vapor deposition technology. In comparison with typical amorphous silicon, the diphasic silicon films possess higher photoconductivity (two orders larger than that of the amorphous silicon film) and fairly good photosensitivity(the r...
Correlation of structural and optical investigation of InGaAs/InAlAs quantum cascade laser
Double X-ray diffraction has been used to investigate InGaAs/InAlAs quantum cascade (QC) laser grown on InP substrate by molecule beam epitaxy, by means of which, excellent lattice matching, the interface smoothness, the uniformity of the thickness and the composition of the epilayer are disclosed. What is more, these results are in good agreement ...
