Effect of internal residual stress on the dielectric properties and microstructure of sputter-deposited polycrystalline (Ba,Sr)TiO3 thin films
Effect of internal residual stress on the dielectric properties and microstructure of sputter-deposited polycrystalline (Ba,Sr)TiO3 thin films
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DOI：
10.1063/1.1903099
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发表时间：
2005-05
影响因子：
3.2
通讯作者：
K. Morito;Toshimasa Suzuki
中科院分区：
文献类型：
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作者：
K. Morito;Toshimasa Suzuki
使用镀铂硅基板上的平行板电容器形式的测试样品，通过实验研究了内部残余应力对溅射沉积多晶 (Ba,Sr)TiO3 薄膜介电性能的影响。不同的沉积压力条件提供了薄膜应力的系统变化，我们发现薄膜面内拉伸应力的减小（主要源于热膨胀失配）对于增加面外方向的介电常数是有效的。另一方面，250 nm 厚的 (Ba,Sr)TiO3 薄膜无法弹性容纳大的面内拉伸应力（超过 1GPa），并且薄膜会通过光学可见的微裂纹形成而松弛。无裂纹 (Ba,Sr)TiO3 薄膜的内部残余应力与介电常数之间的关系可以通过 Landau-Ginsburg-Devonshire 唯象热力学理论得到很好的解释，而无需过渡到...
The role of internal residual stress in the dielectric properties of sputter-deposited polycrystalline (Ba,Sr)TiO3 thin films was studied experimentally using test samples in the form of parallel-plate capacitors on platinized silicon substrate. Different deposition-pressure conditions provided a systematic change in the film stress and we found that a reduction in the in-plane tensile stress of the films (primarily originating from the thermal expansion mismatch) was effective for increasing the dielectric constant in the out-of-plane direction. On the other hand, a large in-plane tensile stress (exceeding 1GPa) cannot be elastically accommodated in a 250-nm-thick (Ba,Sr)TiO3 thin film and the film relaxes through the optically visible microcrack formation. The relationship between the internal residual stress and the dielectric constant of the crack-free (Ba,Sr)TiO3 thin films could be well explained by the phenomenological thermodynamic theory of Landau–Ginsburg–Devonshire, without a transition to the ...