[Bi]:[Te] Control, Structural and Thermoelectric Properties of Flexible BiXTey Thin Films Prepared by RF Magnetron Sputtering at Different Sputtering Pressures
[Bi]:[Te] Control, Structural and Thermoelectric Properties of Flexible BiXTey Thin Films Prepared by RF Magnetron Sputtering at Different Sputtering Pressures
复制标题
DOI：
10.1007/s11664-017-5671-x
复制
发表时间：
2017-11-01
影响因子：
2.1
通讯作者：
Sakulkalavek, Aparporn
中科院分区：
文献类型：
--
作者：
Nuthongkum, Pilaipon;Sakdanuphab, Rachsak;Sakulkalavek, Aparporn
在这项工作中，灵活的BixTey薄膜制备射频（RF）磁控溅射使用Bi 2 Te 3在聚酰亚胺基板上。研究了溅射压力（0.6 Pa ~ 1.6 Pa）对[Bi]：[Te]比、结构和热电性能的影响。通过能量色散谱（EDS）测定薄膜的[Bi]：[Te]比。EDS谱显示了[Bi]：[Te]比随溅射压力的变化。在1.4Pa下沉积的薄膜几乎具有化学计量组成。采用场发射扫描电子显微镜（FE-SEM）、X射线衍射（XRD）和拉曼光谱对不同[Bi]：[Te]比和溅射气压的选择性薄膜的表面形貌、晶体结构和化学结构进行了表征。电输运性质，包括载流子浓度和迁移率，通过霍尔效应测量。塞贝克系数和电导率通过直流四端法（ZEM-3）同时测量。XRD和拉曼光谱的结果表明，BiTe和Bi 2 Te 3之间的微观结构的差异取决于[Bi]：[Te]的比例。电导率和塞贝克系数与晶体和化学结构有关。Bi_2 Te_3薄膜的最大功率因数在室温下为9.5 × 10 ~（-4）W/K ~（-2）m，在195 ℃时增大到12.0 × 10 ~（-4）W/K ~（-2）m。
In this work, flexible BixTey thin films were prepared by radio frequency (RF) magnetron sputtering using a Bi2Te3 target on polyimide substrate. The effects of sputtering pressures, which ranged between 0.6 Pa and 1.6 Pa on the [Bi]:[Te] ratio, and structural and thermoelectric properties were investigated. The [Bi]:[Te] ratio of thin film was determined by energy-dispersive spectrometry (EDS). The EDS spectra show the variation of the [Bi]:[Te] ratio as the sputtering pressure is varied. The film deposited at 1.4 Pa almost has a stoichiometric composition. The selective films with different [Bi]:[Te] ratios and sputtering pressures were characterized by their surface morphologies, crystal and chemical structures by field emission scanning electron microscopy (FE-SEM), x-ray diffraction (XRD) and Raman spectroscopy, respectively. Electrical transport properties, including carrier concentration and mobility, were measured by Hall effect measurements. Seebeck coefficients and electrical conductivities were simultaneously measured by a direct current four-terminal method (ZEM-3). The XRD and Raman spectroscopy results show a difference in microstructure between BiTe and Bi2Te3 depending on the [Bi]:[Te] ratio. Electrical conductivity and Seebeck coefficient are related to the crystal and chemical structures. The maximum power factor of the Bi2Te3 thin film is 9.5 x 10(-4) W/K-2 m at room temperature, and it increases to 12.0 x 10(-4) W/K-2 m at 195 degrees C.