铁电薄膜SrBi_2Ta_(0.6)Nb_(1.4)O_9的光疲劳特性研究

OPTICAL FATIGUE OF SrBi_2Ta_(0.6)Nb_(1.4)O_9 FERROELECTRIC THIN FILMS

用PLD方法在铂金硅衬底制作了高质量的SrB i2Ta0.6Nb1.4O9(SBTN)铁电薄膜样品.研究了SBTN薄膜的电学和光学疲劳特性,分析了其机制.结果显示SBTN铁电薄膜,在电场疲劳下,具有无疲劳特性的优良电学性质;然而,在0.9 V电场下,用200W汞灯疲劳样品,发现光诱导极化疲劳明显,与疲劳前相比,剩余极化下降了51%.这种光诱导剩余极化减小的疲劳,主要机理是光生载流子电畴钉扎.

High quality SrBi2Ta0.6Nb1.4O9 （SBTN） ferroelectric thin films were fabricated on platinized silicon by PLD. Electrical fatigue and optical fatigue of SBTN ferroelectric thin films were studied, respectively. The fatigue mechanisms in the thin films were analyzed. The results indicate the excellent fatigue resistance of electrical properties under electrical fatigue for SBTN ferroelectric thin films. However, by using the illumination of a 200W Hg arc lamp at 0.9V, it was found that the average remanent polarization was dropped by nearly 51% due to the bias/illumination treatment. The optically induced polarization fatigue in SBTN films is due to trapping of photo-generated charge carriers at domain boundaries.