Search

Abstract: We fabricated pn-junction diodes by thermal diffusion of Ag acceptor into n-type melt-grown Mg2Si single-crystalline substrates (electron concentration=2×1015 cm−3) to investigate the infrared photoresponse of the material. The estimated hole concentration at the p-side of the diode diffused with Ag at 550°C was 3×1018 cm−3. Current–voltage measurement of the diodes showed sound rectifying characteristics even at 300K. A clear photoresponsivity with a photon energy threshold of approximately 0.6eV was observed from the diode, showing promise for application in infrared light detection devices at wavelengths of 1.2–2μm. [Copyright &y& Elsevier]

Abstract: Liquid–liquid equilibrium (LLE) measurements for nine binary acetonitrile+ n-alkane (octane, nonane, decane, undecane, dodecane, tridecane, tetradecane, pentadecane, and hexadecane) systems were performed using a laser light scattering technique at moderate pressure from 350K to the upper critical solution temperature. Experimentally determined cloud points for biphasic acetonitrile systems are essential for efficient design and extraction process development for the recently proposed and effective oxidative desulfurization method. These LLE data were satisfactorily correlated with the NRTL equation. [Copyright &y& Elsevier]

We have studied the effect of thermal annealing periods on the optoelectrical properties of Mg2Si pn -junction diodes fabricated by a conventional thermal diffusion process of Ag acceptor. The Au/Ag/ n -Mg2Si (carrier concentration = 2 × 1015cm-3, resistivity = 5-10 Ωcm) substrate was annealed at 550 °C in the Ar-atmosphere using a rapid thermal annealing (RTA) furnace. The annealing periods were varied between 2 and 10 minutes. Clear rectifying behavior of J - V characteristics was observed for the diodes annealed for more than 2 minutes. Spectral responsivity from the photon energy threshold of approximately 0.6 eV was demonstrated with the Mg2Si pn -junction diodes under the zero bias condition at room temperature. The maximum intensity of spectral responsivity was increased with decrease the annealing period. The spectral responsivity of the diode with the RTA periods of 4 minutes was approximately 4 times higher than that of 10 minutes annealed one. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]