Temperature effects on the properties of Ge thin films

The effects of substrate temperature (T-s) on the properties of vacuum evaporated p-type Ge thin films have been investigated for 25 < T-s < 400 degrees C. Increase in the substrate temperature improves the crystallinity and increases the grain size resulting a gradual change from amorphous to polycrystalline structure which was attained above a substrate temperature of 225 degrees C. Low resistive (1 x 10(-2) ohm-cm) and high mobility (280 cm(2)/V . s) films were obtained at T-s = 400 degrees C. It has been observed that the conduction mechanism in polycrystalline films was dominated successively by hopping, tunneling and thermionic emission as the sample temperature was increased from 40 to 400 K. In amorphous samples, conduction was described in terms of different hopping mechanisms. (C) 1999 Kluwer Academic Publishers.


Microwave metamaterial absorber for sensing applications
A metamaterial absorber (MA) based sensor is designed and analysed for various important applications including pressure, temperature, density, and humidity sensing. Material parameters, as well as equivalent circuit model have been extracted and explained. After obtaining a perfect absorption (PA) at around 6.46 GHz and 7.68 GHz, surface current distributions at resonance points have been explained. Since bandwidth and applicability to different sensor applications are important for metamaterial sensor app...
Temperature dependence of the Raman-active phonon frequencies in indium sulfide
Hasanlı, Nızamı; Aydinli, A; Yilmaz, I (1999-01-01)
The temperature dependence of the Raman-active mode frequencies in indium sulfide was measured in the range from 10 to 300 K. The analysis of the temperature dependence of the A(g) intralayer optical modes show that Raman frequency shift results from the change of harmonic frequency with volume expansion and anharmonic coupling to phonons of other branches. The pure-temperature contribution (phonon-phonon coupling) is due to three- and four-phonon processes.
Pressure dependence of the Raman frequencies for the translational mode in ammonia solid II
Yurtseven, Hasan Hamit (Elsevier BV, 2006-12-01)
We study here the translational mode of the ammonia solid II near the melting point by calculating its Raman frequencies as a function of pressure for the fixed temperatures of 230.4, 263.4 and 297.5 K. We perform this calculation of the Raman frequencies using the volume data by means of our Gruneisen relation. The Raman frequency shifts as the volume changes with the pressure, exhibit an anomalous behaviour near the melting point in the ammonia solid II.
Temperature and pressure dependence of molar volume in solid phases of ammonia near the melting point
Yurtseven, Hasan Hamit (Elsevier BV, 2008-08-20)
Temperature and pressure dependencies of the molar volume are studied here along the transition curve between solid I and solid II phases near the melting point in ammonia. The molar volumes are calculated in the temperature range of 217 to 224 K and in the pressure range of 3 to 8 kbar with respect to the triple point (T-t=217.34 K. P-t=3.070 kbar) where the melting curves of solid I and solid II coincide with the transition curve in ammonia.
Temperature effects on the structural and optical properties of the TlInSe2xS2(1-x) mixed crystals (x=0.3)
Omar, A.; Qasrawi, A. F.; Hasanlı, Nızamı (2017-11-15)
In this work, we have studied the temperature effects on the recrystallization process and on the energy band gap of the TlInSe(2)xS(2(1 - x)) mixed crystals at the critical composition (x = 0.3) where structural phase transition from tetragonal to monoclinic takes place. Remarkable effect which included permanent recrystallization process, enlargements in the monoclinic crystallite size, decreases in the compressing strain and in the dislocation density as well as in the stacking faults and in the energy b...
Citation Formats
İ. Günal, “Temperature effects on the properties of Ge thin films,” JOURNAL OF MATERIALS SCIENCE, pp. 5033–5037, 1999, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/41379.