TY - JOUR
T1 - Precipitation phenomena in and electrical resistivity of high-temperature treated langatate (La3Ta0.5Ga5.5O14)
AU - Yaokawa, Ritsuko
AU - Kimura, Hiromitsu
AU - Aota, Katsumi
AU - Uda, Satoshi
N1 - Funding Information:
Manuscript received november 7, 2010; accepted March 29, 2011. This work was partly supported by a Grant-in-aid to promote basic research by research personnel in private-sector business no. b210171 from the Japan science and Technology agency. r. yaokawa and K. aota are with citizen Holdings co., ltd., Tokoro-zawa, saitama, Japan (e-mail: yoshimurar@citizen.co.jp). H. Kimura and s. Uda are with the Institute for Materials research, Tohoku University, sendai, Miyagi, Japan. digital object Identifier 10.1109/TUFFc.2011.1922
PY - 2011/6
Y1 - 2011/6
N2 - La3Ta0.5Ga5.5O14 (LTG) single crystals, which have no phase transition up to the melting point, were heat-treated in air at temperatures from 1000°C to 1450°C for 10 h. LaTaO4 (LT) and LaGaO3 (LG), which coexist with LTG in the three-phase region on the Ga-poor side, precipitated on the surface of the crystal for heat treatments above 1300°C because of Ga evaporation during the heat treatment. The Ga-poor state near the surface of the 1450°C heat-treated specimen was confirmed by electron probe micro-analysis measurements. The electrical resistivity of LTG single crystals decreased by heat treatment in the range of 1000°C to 1200°C for 10 h in air, where no precipitation was observed, whereas the resistivity increased with heat treatment over 1400°C for 10 h in air. The electrical resistivity of the Ga-poor surface region was higher than that of the interior.
AB - La3Ta0.5Ga5.5O14 (LTG) single crystals, which have no phase transition up to the melting point, were heat-treated in air at temperatures from 1000°C to 1450°C for 10 h. LaTaO4 (LT) and LaGaO3 (LG), which coexist with LTG in the three-phase region on the Ga-poor side, precipitated on the surface of the crystal for heat treatments above 1300°C because of Ga evaporation during the heat treatment. The Ga-poor state near the surface of the 1450°C heat-treated specimen was confirmed by electron probe micro-analysis measurements. The electrical resistivity of LTG single crystals decreased by heat treatment in the range of 1000°C to 1200°C for 10 h in air, where no precipitation was observed, whereas the resistivity increased with heat treatment over 1400°C for 10 h in air. The electrical resistivity of the Ga-poor surface region was higher than that of the interior.
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U2 - 10.1109/TUFFC.2011.1922
DO - 10.1109/TUFFC.2011.1922
M3 - Article
AN - SCOPUS:79959550731
SN - 0885-3010
VL - 58
SP - 1131
EP - 1139
JO - IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
JF - IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
IS - 6
M1 - 5895026
ER -