Effects of Manganese Doped Ba1.002(Ti0.82Zr0.18)O3+δ on Insulation Resistance and dielectric Properties

• Main Authors: Chi-Wei Chu, 朱啟維
• Other Authors: Kuan-zong Fung
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/15978193169283939097

碩士 === 國立成功大學 === 材料科學及工程學系碩博士班 === 93 === 　　In this study, we modified A-site and B-site cation ratio in perovskite(ABO3) structure by adding different amounts of manganese. To investigate manganese adding could accompany the effects on structure stability and microstructure changes in commercial Ba1.002(Ti0.82Zr0.18)O3+δ(BTZ) in reducing sintering condition. Furthermore, adjusted it’s A/B cation ratio can cause various defects in structure. We induced the defect charge carriers by manganese inhibiting Ba1.002(Ti0.82Zr0.18)O3+δ insulation resistance properties degradation according to defects chemical equation . This study divided in two parts: (1) :It means as doped manganese as well as equal concentration barium into BTZ structure. It can help us to modify A-site cation always excess 0.002 mole than B-site cation. We doped y from 0.005 to 0.05 mole. Then we chose two reducing atmospheres “dry and moist” 97%N2-3%H2 mixed gaseous and sintered at 1300℃ for 4hr. In this study, XRD diffraction pattern could help us to know barium rich composition sintered at dry reducing condition would segregated barium rich second phase “Ba2TiO4”. The barium rich composition (A-site excess 0.002) after sintering is obtained porous structure in both reducing conditions. IR (insulation resistance) measurement after sintering in dry condition obtained from 107Ω-cm (un-doped BTZ) to 109Ω-cm(2mol%Mn).And raise to 1010Ω-cm after sintered in moist condition. (2) :It represents x mole manganese doped into BTZ perovskite structure B-site lattice point that can decrease A/B cation ratio. From SEM observation, it indicates that adjustment of A/B cation ratio would change microstructure. A/B cation ratio under 1 could results densification as sintered in both reducing conditions. IR increase obviously from 107Ω-cm to 1011Ω-cm in dry condition and further is raised to 1012Ω-cm in moist condition as 3 mol% Mn doped.