Temperature Dependence of the Electrical Resistivity of Polymerized C60 Thin Films

2002 ◽  
Vol 734 ◽  
Author(s):  
R. Govinthasamy ◽  
J. H. Rhee ◽  
S. C Sharma
Keyword(s):  
Thin Films ◽  
Electrical Resistivity ◽  
Temperature Dependence ◽  
Uv Irradiation ◽  
High Vacuum ◽  
Single Crystal Silicon ◽  
Laser Raman Spectroscopy ◽  
Crystal Silicon ◽  
Laser Raman ◽  
Electrical Resistivities

ABSTRACTHighly conducting thin films of C60 were deposited by thermal evaporation in high vacuum on single crystal silicon substrates. The microstructure of the films was characterized by using Atomic Force Microscopy, and laser Raman spectroscopy. The films were polymerized by uv irradiation. The dc electrical resistivities of the as-deposited and uv-polymerized films were measured as functions of temperature between 295 and 17K by the four-probe technique. We present results on the effects of uv-irradiation on the surface microstructure and the temperature dependence of the electrical resistivity of these films.

Photoelectron Spectroscopy Measurements of the Valence Band Structures of C60 Thin Films on Single Crystal Silicon and Polycrystalline Copper

2002 ◽  
Vol 734 ◽  
Author(s):  
B. Ha ◽  
J. H. Rhee ◽  
Y. Li ◽  
D. Singh ◽  
S. C. Sharma
Keyword(s):  
Thin Films ◽  
Single Crystal ◽  
Valence Band ◽  
Photoelectron Spectroscopy ◽  
Thermal Evaporation ◽  
High Vacuum ◽  
Single Crystal Silicon ◽  
Polycrystalline Copper ◽  
Band Structures ◽  
Crystal Silicon

ABSTRACTWe have used photoelectron spectroscopy to study possible modifications in the electronic valence band structures of thin films of C60 due to their deposition on single crystal silicon and polycrystalline copper. The C60 thin films were deposited by thermal evaporation under high vacuum and further characterized by using Raman spectroscopy. We observe significant differences in the valence band structures of C60 thin films deposited on these substrates and attribute them to interactions at the interface.

Irradiation Effect on Al-Dispersed Amorphous Silicon Thin Films by Femtosecond Laser

2020 ◽  
Vol 984 ◽  
pp. 91-96
Author(s):  
Cheng Liu ◽  
Yu Hao Song ◽  
Dong Yang Li ◽  
Wei Li
Keyword(s):  
Thin Films ◽  
Amorphous Silicon ◽  
Laser Raman Spectroscopy ◽  
Irradiation Effect ◽  
Amorphous Thin Films ◽  
Laser Raman ◽  
Silicon Thin Films ◽  
Al Nanoparticles ◽  
Spot Area ◽  
Fs Laser

The structural and optical properties of amorphous silicon (a-Si) and Al-dispersed amorphous silicon (a-Si:Al) thin films irradiated by femtosecond (fs) laser at various energy densities are investigated comparatively in this article. It is found that there is an uneven crystallization in both amorphous thin films by means of optical microscopy and laser Raman spectroscopy respectively. The crystallization in each pulse spot area is gradually weakened from the center to the edge along with the energy dispersion of laser irradiation. The laser induced crystallization in a-Si thin films begins early and develops more extensively compared to that in a-Si:Al thin films, and Al nanoparticles inhibit somehow the crystallization of a-Si in a-Si:Al thin films.

TEMPERATURE DEPENDENCE OFRHSIN ALUMINUM‐IMPLANTED LAYER INn‐TYPE SINGLE CRYSTAL SILICON

1969 ◽  
Vol 14 (9) ◽  
pp. 255-258 ◽  
Author(s):  
Tadatsugu Itoh ◽  
Taroh Inada ◽  
Masao Ishiki ◽  
Kenshi Menabe
Keyword(s):  
Single Crystal ◽  
Temperature Dependence ◽  
Single Crystal Silicon ◽  
Crystal Silicon

scholarly journals Possible causes of electrical resistivity distribution inhomogeneity in Czochralski grown single crystal silicon

2019 ◽  
Vol 5 (1) ◽  
pp. 27-32 ◽  
Author(s):  
Svetlana P. Kobeleva ◽  
Ilya M. Anfimov ◽  
Vladimir S. Berdnikov ◽  
Tatyana V. Kritskaya
Keyword(s):  
Electrical Resistivity ◽  
Single Crystal ◽  
Single Crystals ◽  
Crystallization Front ◽  
Single Crystal Silicon ◽  
Theoretical Interpretation ◽  
Azimuthal Direction ◽  
Crystal Silicon ◽  
Wide Range ◽  
Possible Cause

Electrical resistivity distribution maps have been constructed for single crystal silicon wafers cut out of different parts of Czochralski grown ingots. The general inhomogeneity of the wafers has proven to be relatively high, the resistivity scatter reaching 1–3 %. Two electrical resistivity distribution inhomogeneity types have been revealed: azimuthal and radial. Experiments have been carried out for crystal growth from transparent simulating fluids with hydrodynamic and thermophysical parameters close to those for Czochralski growth of silicon single crystals. We show that a possible cause of azimuthal electrical resistivity distribution inhomogeneity is the swirl-like structure of the melt under the crystallization front (CF), while a possible cause of radial electrical resistivity distribution inhomogeneity is the CF curvature. In a specific range of the Grashof, Marangoni and Reynolds numbers which depend on the ratio of melt height and growing crystal radius, a system of well-developed radially oriented swirls may emerge under the rotating CF. In the absence of such swirls the melt is displaced from under the crystallization front in a homogeneous manner to form thermal and concentration boundary layers which are homogeneous in azimuthal direction but have clear radial inhomogeneity. Once swirls emerge the melt is displaced from the center to the periphery, and simultaneous fluid motion in azimuthal direction occurs. The overall melt motion becomes helical as a result. The number of swirls (two to ten) agrees with the number of azimuthally directed electrical resistivity distribution inhomogeneities observed in the experiments. Comparison of numerical simulation results in a wide range of Prandtl numbers with the experimental data suggests that the phenomena observed in transparent fluids are universal and can be used for theoretical interpretation of imperfections in silicon single crystals.

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