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N-type Conductivity (n-type + conductivity)
Selected AbstractsProperties of InAs co-doped ZnO thin films prepared by pulsed laser depositionCRYSTAL RESEARCH AND TECHNOLOGY, Issue 12 2009J. Elanchezhiyan Abstract InAs co-doped ZnO films were grown on sapphire substrates by pulsed laser deposition. The grown films have been characterized using X-ray diffraction (XRD), Hall effect measurements, Atomic force microscope (AFM) and Field emission scanning electron microscope (FESEM) in order to investigate the structural, electrical, morphological and elemental properties of the films respectively. XRD analysis showed that all the films were highly orientated along the c-axis. It was observed from Hall effect measurements that InAs co-doped ZnO films were of n-type conductivity. In addition, the presence of In and As has been confirmed by Energy dispersive X-ray analysis. AFM images revealed that the surface roughness of the films was decreased upon the co-doping. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Optical, structural, and electrical properties of Cu2O thin filmsPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 7 2010Ferid Chaffar Akkari Abstract Glancing-angle deposition (GLAD) was used in this work to grow transparent oxide Cu2O thin films by annealing in air at 185,°C of copper films deposited firstly by this method onto glass substrates. The annealing temperature of 185,°C corresponds to the optimal temperature that corresponds to the formation of Cu2O phase. The copper was sculptured into a zigzag shape, which present case (i) one column with inclined angle ,, case (ii) two columns with inclined angles , and ,,, and case (iii) three copper inclined columns with inclined angles ,, ,,, and , where , is the deposition angle between the incident flux and the substrate surface normal. The films after annealing have thicknesses of 165, 185, and 265,nm for cases (i), (ii), and (iii), respectively. The air-annealed copper films were characterized for their structural, surface morphological; electrical and optical properties by using X-ray diffraction (XRD), scanning electron microscopy (SEM), electrical resistivity, and optical (transmittance and reflectance) measurement techniques. Optical studies show a direct allowed transition around 2.5,eV for the three cases. High absorptions coefficients in the range 2,×,105,3.7,×,106,cm,1 were found for photon energies higher than 2.7,eV. The Cu2O films exhibit in cases (i) and (ii) p-type conductivity but in case (iii) the Cu2O films exhibit n-type conductivity. [source] Optoelectronic properties of transparent p-type semiconductor CuxS thin filmsPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 7 2010P. Parreira Abstract Nowadays, among the available transparent semiconductors for device use, the great majority (if not all) have n-type conductivity. The fabrication of a transparent p-type semiconductor with good optoelectronic properties (comparable to those of n-type: InOx, ITO, ZnOx or FTO) would significantly broaden the application field of thin films. However, until now no material has yet presented all the required properties. Cu2S is a p-type narrow-band-gap material with an average optical transmittance of about 60% in the visible range for 50,nm thick films. However, due to its high conductivity at room temperature, 10,nm in thickness seems to be appropriate for device use. Cu2S thin films with 10,nm in thickness have an optical visible transmittance of about 85% rendering them as very good candidates for transparent p-type semiconductors. In this work CuxS thin films were deposited on alkali-free (AF) glass by thermal evaporation. The objective was not only the determination of its optoelectronic properties but also the feasibility of an active layer in a p-type thin film transistor. In our CuxS thin films, p-type high conductivity with a total visible transmittance of about 50% have been achieved. [source] Implementation of the GaN lateral polarity junction in a MESFET utilizing polar doping selectivityPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 1 2010Ramón Collazo Abstract The difference in surface energies between the Ga-polar orientation and the N-polar orientation of GaN translates into a completely different behavior for the incorporation of intentional and unintentional impurities. Oxygen is found to be an impurity with higher concentration in the N-polar films than in Ga-polar films and is the cause of n-type conductivity observed in N-polar films. Utilizing this doping selectivity we fabricated a depletion-mode metal-semiconductor field effect transistor (MESFET) with n-type N-polar domains as source and drain and a Ga-polar channel on polarity-patterned wafers. The difference in the electronic properties of the different domains, i.e., as-grown N-polar domains are n-type conductive and Ga-polar domains are insulating, allows for laterally selective doped areas that can be realized for improving contact resistance to the n-type conduction channel. Basically, the N-polar domains acted as the ohmic contacts to the channel localized in a Ga-polar domain. A MESFET with a Schottky gate was fabricated as an example of implementation of this novel structure showing a lowering in the specific contact resistivity. [source] Electron paramagnetic resonance study of phosphorus-doped n-type homoepitaxial diamond films grown by chemical vapor depositionPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 13 2006M. Katagiri Abstract Electron paramagnetic resonance technique has been applied to identify the microscopic origin of the n-type conductivity in phosphorus-doped {111}-homoepitaxial diamond films grown by chemical vapor deposition. The NIMS-1 center having the D2d symmetry with g|| = 1.9983, g^ = 2.0072 and the 31P hyperfine interaction of A|| = 5.77 mT, A, = 1.21 mT at 30 K is identified to be arising from the phosphorus donors based on the number of spins which matches to the number of the electrically active phosphorus atoms in the films. The wave function of the unpaired electron is localized by 12% on the phosphorus atom with a predominant p-character. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Synthesis and Seebeck coefficient of nanostructured phosphorus-alloyed bismuth telluride thick filmsPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 11 2008Jian Zhou Abstract Phosphorous-alloyed Bi2Te3 thick films have been prepared by electrochemical deposition. The average grain size of the films was calculated to be 14-26 nm based on Scherrer's equation. The effect of P on the Seebeck coefficient of thermoelectric P-alloyed Bi2Te3 thick film was investigated. The results show that P-alloyed thick film has n-type conductivity with the Seebeck coefficient of -35 ,V/K. The correlation between P site occupancy in the crystal and the Seebeck coefficient was discussed. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | ||||||||||