Dielectric Characteristics Investigation of (Ba0.7Sr0.3)(Ti0.9Zr0.1)O3 Ferroelectric Thin Films

Kai-Huang Chen1, Da-Huei Lee2, Wen-Shan Chen2, Chien-Min Cheng2,*, Yi-Pin Lin3 1Department of Electronics Engineering and Computer Science, Tung-Fang Design University, Kaohsiung, Taiwan,

R.O.C.2Department of Electronic Engineering, Southern Taiwan University of Science and Technology, Tainan, Taiwan, R.O.C.

3Department of Interior Design, Tung-Fang Design University, Kaohsiung, Taiwan, R.O.C.

By the radio frequency (RF) magnetron sputtering methods, (Ba0.7Sr0.3)(Ti0.9Zr0.1)O3 ferroelectric thin films were deposited on the Pt/Ti/SiO2/Si(100) substrate to form a Metal/Insulator/Metal structure. Under the optimal deposition conditions (RF power was 160 W, oxygen concentration was 25 %, substrate temperature was 580 C, and chamber pressure was 0.075 mPa), the (111) and (110) oriented polycrystalline of the BSTZ thin films grow easily. And under 0.5 MV/cm bias, the dielectric constant and leakage current density of the BSTZ thin films were improved to 191 and 3×10-8 A/cm2, respectively. In addition, under various measured temperatures (0 ~ 80 C) and frequencies (100 kHz ~ 1 MHz), all the dielectric constants remain almost unchanged. Compared to BSTZ thin films reported previously, in this study, the deposited thin films have the advantage of lower leakage current and hence are suitable for the applications of DRAM.

The 2th International Conference on Advanced Electromaterials (ICAE 2013)

AFM images of the BSTZ thin films deposited at (a) 30 min (b) 45 min and (c) 60 min

Leakage current density of BSTZ thin films under various (a) RF power (b) substrate temperature (c) chamber pressure (d) oxygen concentration

SEM cross-section images of the BSTZ thin films.

XRD patterns of the BSTZ thin films deposited under various (a) RF power (b) substrate temperature (c) chamber pressure and (d) oxygen concentration