Comparative Study on Electrical and Dielectric Properties of Sintered Nano and Micro Silicon Nitride Ceramics

In the present work we have studied the electrical conductivity, dielectric constant and dielectric loss of Sintered Silicon Nitride ceramics. In this study it was found that the grain size has great impact on electrical conductivity and dielectric properties of Sintered Silicon Nitride Ceramics. The result shows more efficiency of electrical and dielectric properties with nano sized grains. The sintering was performed in a programmable furnace at 950 K. The dc conductivity measured in the temperature range 300 K to 900 K. At higher temperature (T > 800 K), the dc conductivity increases exponentially with temperature for both of the investigated samples. Dielectric constant and loss are measured in the temperature range 300 K to 900 K with frequency range 1 KHz to 1 MHz. To confirm the grain size, the samples are characterized by the Scanning Electron Microscope (SEM). These types of samples can be used as a high temperature semi-conducting materials.