High-performance electrical properties of La-based perovskite ceramics for the functional phase of thick film resistors

Abstract

In order to explore an economical functional phase alternative material for thick lm resistors, the crystal structure, microstructure, and electrical properties of (1-x)LSCN + xLCNZ (x = 0.0-1.0) composite ceramics were studied through solid-state reaction experiments. The composite ceramics were characterized by xray diffraction, scanning electron microscopy, energy dispersive x-ray spectroscopy, and DC four-probe method. Results suggested that the main phases of LSCN and LCNZ were formed, along with a small part of impurity phases. The addition of LCNZ to LSCN decreased the electrical conductivity and changed the TCR from positive to negative. Zero TCR could be achieved around 0.6 < x < 0.8 and relatively low absolute TCR values could be obtained for the samples of 0.4 ≤ x ≤ 0.8. The ceramic of 0.6LSCN + 0.4LCNZ showed the optimal performances of conductivity = 1923 S/cm, TCR = 379.54 ppm/℃, and relative density = 95.05%.