LNO薄膜的射频磁控溅射制备及其电学性能与红外吸收性能

ELECTRIC AND INFRARED ABSORPTION PROPERTIES OF LNO THIN FILMS PREPARED BY RF-MAGNETRON SPUTTERING

用磁控溅射法在S i(111)基片上以不同溅射功率沉积LaN iO3(LNO)薄膜,基片温度370℃,对沉积的薄膜样品进行快速热退火处理(500℃,10 m in)。使用电感耦合等离子体原子发射光谱(ICP-AES)精确测量不同溅射功率沉积的LNO薄膜退火前后的组分情况。分析发现:LNO薄膜经退火处理后,其中的N i/La的比值随着溅射功率增大而越接近理想比1:1,其导电性能也越好。另外,我们以相同工艺制备了不同厚度的LNO薄膜顶电极,四探针电阻测试仪和红外椭圆偏振光谱仪测试其电学与红外吸收性能,实验发现:(1)LNO薄膜的电阻率随膜厚的增加而降低,在大约300 nm厚时略又有增加趋势;(2)LNO薄膜的红外吸收系数随其厚度的增加而增加,且随红外波长的增大而减小。

LaNiO3 （LNO） thin films were deposited on Si（ 111 ） substrates by RF - magnetron sputtering with different power at low substrate temperature （ Tsub = 370 ℃ ）, sequentially followed by a rapid thermal annealing （RTA） process at 500 ℃ for 10 minutes. The composition of the as - prepared and annealed LNO thin films prepared with different sputtering power were investigated by inductively coupled plasma atom emission spectroscopy （ICP - AES）. It was found that： As the sputtering power increasing, the ratio of Ni/La in the annealed LNO thin films is close to the ideal than 1 ： 1, thus its conductive performance become better. In addition, the top electrode of LNO thin films with different thickness were prepared with the same technics, then investigated by four - probe meter and spectro - ellipsometer, respectively. It is found that ： （ 1 ） The resistivity of LNO thin films is reduced with increase of its thickness, and there exist a slightly increasing tendency when reached to about 300 nm; （2） The infrared absorption coefficient of LNO thin films is increased with increase of its thickness, and reduced with increase of the infrared wavelength.