Microwave Dielectric Properties of A‐Site Modified Ba(Co_0.7Zn_0.3)_1/3Nb_2/3O₃ by La³⁺

Abstract

The sintering behavior, ordering state, and microwave dielectric properties of Ba1−xLa2x/3(Zn0.3Co0.7)1/3Nb2/3O3 Ceramics (0≤x≤0.06) were investigated in this paper. The X‐ray diffraction (XRD) results show that all samples exhibit a single perovskite phase except for the sample with x≥0.03. The sinterability is slightly improved by La doping. The long range order (LRO) degree on B‐site is greatly increased with the increase of x value up to x=0.015 and then slightly decreased with the further increase of x due to the increasing amount of second phases. The dielectric constant at microwave frequency decreases slightly with the increase of x when x<0.015 and increases slightly with further increasing x for the samples sintered at 1375°C/10 h. The Q×f value increases with x up to x=0.015 and then decreases with further increase of x, which is consistent with the variation trend of LRO degree. The τf value decreases slightly with the increase of x up to 0.006, then increases greatly with the further increase of x. An optimized dielectric properties of ɛr=34, Q×f=63 159, GHz and τf=5.21 ppm/°C were obtained for the x=0.01 sample sintered at 1425°C/10 h.

Structure and microwave dielectric properties of Ba[(Mg 1−x Ni x ) 1/3 Nb 2/3 ]O 3 ceramics

“…7 In the previous work [23], volatilization of Ni occurred in the preparation process, however, no detailed investigation was performed for its effects on the structure and microwave dielectric properties. As the volatilization of Co has been reported to occur in the Ba(Co1/3Nb2/3)O3-Ba(Zn1/3Nb2/3)O3 system and affect the microstructure and microwave dielectric properties [31,32], the volatilization of Ni in the present system should play the same role. In the Ba(Co1/3Nb2/3)O3-Ba(Zn1/3Nb2/3)O3 system, the volatilization of Co was found to result in secondary phases.…”

Microwave dielectric properties of Ba(Co0.56Y0.04Zn0.35)1/3Nb2/3+x O3(x = −0.004 ~ 0.008) ceramics

“…The difficult control of the B-site ordering degree and valence state of Co should be mainly responsible for the poor reproducibility of Q 9 f values [3]. Thus, the effect of A-site [7,23] and B-site [2,24] nonstoichiometry [22,25,26] and substitution [5,16,21] on the structure, sinterability and microwave dielectric properties of BCZN have been extensively studied to tackle this challenge.…”

Effects of Y2O3 substitution on microwave dielectric properties of Ba(Co0.6Zn0.38)1/3Nb2/3O3 ceramics

“…It also indicated that the amount of Ba 8 CoNb 6 O 24 phase increased slightly as the addition amount was increased from 0 to 0.06. We have found that the Ba 8 CoNb 6 O 24 phase commonly appeared in the BCN or BZN system [2,16,29]. It is well acknowledged that the appearance of Ba 8 CoNb 6 O 24 phase can worsen the the microwave dielectric properties.…”

“…They are widely used as substrates for integrated circuits, mounting, dielectric filters, dielectric antennas, and dielectric resonators in passive microwave components [1][2][3]. A(B 0 1/3 B 00 2/3 )O 3 (A = Ba; B 0 = Zn 2?…”