半导体热电材料Bi2Te3膜的电化学制备

研究了不同沉积电位对电化学生长半导体热电材料Bi2Te3膜沉积过程、膜形貌、结晶性及相结构的影响。利用I-V循环扫描曲线分别研究了纯Bi3 、纯Te4 及其两种离子的混合溶液电化学特性;应用扫描电子显微镜(SEM)、X射线衍射(XRD)、电子能谱(EDS)对膜的微观表面形貌、相结构及成分进行了表征。研究表明:生长的样品为斜方六面体(rhombohedral)晶体结构的Bi2Te3,薄膜表面平整致密,为明显的柱状晶结构,具有(110)择优取向;沉积电位越接近还原峰最大电流处,膜的生长电荷效率越高,薄膜结晶性也越好。

Fabrication of Thermoelectric Material Bi2Te3 Films by Electrodeposition

Semiconductor Bi2Te3 is a very important thermoelectric materials.High quality Bi2Te3 thin film plays a key role in the high-integrated,larger area thermoelectric devices.High quality Bi2Te3 semiconductor films were deposited by electrochemical method.The influences of electrodeposition parameters on the morphology,microstructure,crystal orientation,and deposition efficiency of Bi2Te3 films were investigated.The electrochemical processes of pure Bi3 ,pure Te4 and their mixed solutions were compared through cyclic voltammogram experiments.SEM,EDS and XRD were used to characterize the morphology,composition and crystal structure of the films.Despite the different deposited potentials,all the as-grown Bi2Te3 films were rhombohedral crystal structure with preferred orientation texture,and with column grains.The more negative is the deposition potential,the greater the deposition current,and the deposited film is more thicker and has a better crystalline structure.