Sage Journals: Discover world-class research

Abstract

Extremely large piezoresistance (stress-sensitive resistance), equivalent to a value of the gage factor (the magnitude of resistance change per strain) of > 10⁷ was observed in single grain boundaries formed in thin semiconducting barium titanate ceramic bars at room temperature. The samples were produced to have a grain structure consisting of single grains joined together in series and a diameter in the range 10-20,um. In this study, observation of ferroelectric domain structures and measurements of resistance were simultaneously carried out for some samples under cyclic mechanical stresses to closer look at the influence of the morphological change of ferroelectric domain structures on the grain boundary resistance in the materials. In a bar sample with a single grain boundary, a 90° domain wall was observed to appear and move from one end of the sample to the other during one cycle of the stress applied. It has been found that the observed large piezoresistance is closely connected with a drastic change of the domain structure in the vicinity of grain boundaries in the samples.

Get full access to this article

View all access options for this article.

References

Alles, A. B. et al. 1995. "Piezoresistivity Modeling of Grain-Boundary Junctions in Positive Temperature Coefficient of Resistivity BaTiO3" J. Appl. Phys., 77 (10); 5322-5334.

Amin, A. 1989. "Piezoresistivity in Semiconducting Positive Temperature Coefficient Ceramics," J. Am. Ceram. Soc., 72 (3): 369-376.

Capurso, J. S. et al. 1995. "Processing of Laminated Barium Titanate Structures for Stress-Sensing Applications," J. Am. Ceram. Soc., 78 (9): 2476-2480.

Heywang, W 1964. "Resistivity Anomaly in Doped Barium Titanate," J. Am. Ceram. Soc., 47 (10): 484-490.

Kuwabara, M. et al. 1996. "Single-Grain boundaries in PTC Resistors," J. Am. Ceram. Soc., 79 (4): 997-1001.

Kuwabara, M. et al. 1997. "Differential Negative Resistance and Piezoresistivity in Thin Semiconducting BaTiO3 Ceramic Bars," J. Am. Ceram. Soc., 80 (7): 1881-1884.

Kuwabara, M. et al. 1998. "Giant Piezoresistive Effects in Single Grain Boundaries of Semiconducting Barium Titanate Ceramics," J. Electroceramics, in press.

Matsuda, H. 1998. "Stress-Induced Resistivity Anomaly in Semiconducting Barium Titanate Ceramic Wire," J. Am. Ceram. Soc., 81 (1): 229-232.

Saburi, O. 1960. "Piezoresistivity in Semiconductive Barium Titanates," J. Phys. Soc. Jpn., 15: 733-734.

Domain-Wall Motion under Mechanical Stresses and Giant Piezoresistivity in Thin Barium Titanate Ceramic Bars

Abstract

Get full access to this article

References