Mechanical and Dielectric Properties of InTe Crystals

Teena Mathew, Ayyappacharuparambil Gopalanachary Kunjomana, Keelapattu Munirathnam, Kunnath Appukuttan Chandrasekharan, Muthukrishnan Meena, Chelliah Kamalakshiammal Mahadevan

Physics Research Centre, S. T. Hindu College, Nagercoil, India.
Research Centre, Department of Physics, Christ University, Bangalore, India.

DOI: 10.4236/csta.2012.13015                

Abstract

The mechanical properties of indium telluride (InTe) crystals grown by the Bridgman technique were investigated at room temperature using a Vickers hardness tester. The microhardness is observed to vary nonlinearly with the applied load, 10 - 100 g. The cleaved ingots are found to have high value of microhardness (222.44 kg/mm² at a load of25 g), which reflects an appreciable degree of strength due to their covalent bonding and homogeneity. The studies revealed that the dislocations in the grown crystals offered a resistance to fresh dislocations due to interaction. At higher loads, plastic deformation induces by slip, exhibiting a decrease in hardness from the peak value. The dielectric constant and dielectric loss of indium telluride crystals were evaluated in the frequency range, 1 kHz - 1 MHz for different temperatures (35^oC - 140^oC). The frequency dependence of AC conductivity was analyzed as a function of temperature. The effect of temperature and frequency on the dielectric response of InTe crystals has been assessed on their cleavage faces and the obtained results are discussed.

Keywords

Indium Telluride; Bridgman Technique; Microhardness; Dielectric Constant; Dielectric Loss; AC Conductivity

Conflicts of Interest

The authors declare no conflicts of interest.

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