Large remanent polarization of 100% polar-axis-oriented epitaxial tetragonal Pb(Zr0.35Ti0.65)O3 thin films
Large remanent polarization of 100% polar-axis-oriented epitaxial tetragonal Pb(Zr0.35Ti0.65)O3 thin films
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DOI：
10.1063/1.1586993
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发表时间：
2003-06-30
影响因子：
4
通讯作者：
Saito, K
中科院分区：
文献类型：
--
作者：
Morioka, H;Asano, G;Saito, K
生长了100％极轴（c轴）取向的外延Pb（Zr0.35Ti0.65）O-3（PZT）薄膜，并直接测量了它们的大剩余极化（P-r）。当沉积温度升高至540℃且膜厚减小至50 nm时，在(100)(c)SrRuO3//(100)SrTiO3衬底上获得了完全c轴取向的外延PZT薄膜。极化电场磁滞回线充分饱和并且具有方形形状。 50 nm厚薄膜的P-r在0.9 V时饱和，其值超过90 muC/cm(2)；在 20 Hz 至 1 kHz 范围内几乎与测量频率无关。考虑到只有c轴取向域对偏振有贡献这一事实，该值与具有相同组成的a轴和c轴混合取向外延PZT膜的估计值非常一致。另一方面，完全c轴取向膜的矫顽磁场值为140kV/cm，与相同膜厚的混合取向膜几乎相同。这些结果表明PZT具有较大的P-r，适用于高密度铁电随机存取存储器。 (C) 2003 年美国物理研究所。
100% polar-axis (c-axis)-oriented epitaxial Pb(Zr0.35Ti0.65)O-3 (PZT) thin films were grown and their large remanent polarization (P-r) was directly measured. Perfectly c-axis-oriented epitaxial PZT thin films were obtained on (100)(c)SrRuO3//(100)SrTiO3 substrates when the deposition temperature increased to 540 degreesC together with a decrease in the film thickness down to 50 nm. Polarization-electric-field hysteresis loops were well saturated and had a square shape. The P-r of a 50 nm thick film saturated at 0.9 V, and its value was over 90 muC/cm(2); almost independent of the measurement frequency within the range from 20 Hz to 1 kHz. This value was in good agreement with the estimated one from the a- and c-axes mixture-oriented epitaxial PZT film having the same composition taking into account the fact that only the c-axis-oriented domain contributed to the polarization. On the other hand, the coercive field value of a perfectly c-axis-oriented film was 140 kV/cm and almost the same as that of the mixture-oriented one having the same film thickness. These results show that PZT has a large P-r applicable for high-density ferroelectric random access memory. (C) 2003 American Institute of Physics.