Effects of BN Dopant on Electrical Characteristics of Barium-Excessive BaTiO₃ Ceramics for Laminated Positive Temperature Coefficient Thermistors Fabricated by Tape Casting Technique

Abstract:

The barium-excessive BaTiO₃ ceramics with BN addition for laminated positive temperature coefficient (PTC)thermistors are fabricated. The tape casting technique and reduction/reoxidation process are employed into the fabricating procedure. The influences of BN additive on ceramic characteristics are discussed. The addition over 5% leads to rectangular and abnormal large grains. The 5% BN-doped ceramics shows a resistivity of 233 Ω•cm and PTC jump of 3.4 orders of magnitude. The charge carrier density in grain bulk and acceptor state density at grain boundaries are evaluated. The correlation of BN doping amount with room temperature resistivity, PTC jump, reoxidation effect as well as charge carrier and acceptor state density are investigated.

• Periodical: Advanced Materials Research (Volumes 415-417)
• Pages: 994-999
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.415-417.994
• Online since: December 2011
• Authors: Bin Bin Chen, Shu Ping Gong, Jian Qiao Liu, Lian Hua Li, Dong Xiang Zhou
• Keywords: Barium Titanate (BT), Boron Nitride, Laminate Device, PTCR, Tape Casting Technique

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