Ceramic Nanoparticle Synthesis at Lower Temperatures for LTCC and MMIC Technologies

Abstract

Ni <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1-x</sub> Mg <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> Fe <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> (x = 0.2-0.8) nanoparticles are prepared by hydrothermal synthesis followed by microwave processing. The effect of microwave processing in reducing the required heat treatment is discussed. The samples are characterized by powder X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometer, and LCR bridge. Microwave processing has enhanced the chemical reaction to form ferrites without any stray ferric oxide phases. Microscopic images have confirmed that the particles still retain nanoscale after microwave processing. An appreciably high magnetic moment is noticed. The experimental magnetic moment is used to estimate the cation distribution in tetrahedral and octahedral sites. Temperature and frequency dependence of initial permeability is discussed in the light of magnetic spin canting.