PdSe_(2)半导体薄膜的真空硒化法制备研究  

Electronic Property of PdSe_(2) Thin Films Fabricated by Post-selenization of Pd Films

作　　者：王慧[1,2] 张淑娟 陈亭伟 张传林[1] 罗豪甦 郑仁奎 WANG Hui;ZHANG Shujuan;CHEN Tingwei;ZHANG Chuanlin;LUO Haosu;ZHENG Renkui(Jiangxi Engineering Laboratory for Advanced Functional Thin Films,School of Materials Science and Engineering,Nanchang University,Nanchang 330031,China;Shanghai Institute of Ceramics,Chinese Academy of Sciences,Shanghai 200050,China;School of Materials,Mechanic,and Electrical Engineering,Jiangxi Science and Technology Normal University,Nanchang 330038,China)

机构地区：[1]南昌大学材料科学与工程学院,江西省先进功能薄膜材料工程实验室,南昌330031 [2]中国科学院上海硅酸盐研究所,上海200050 [3]江西科技师范大学材料机械工程学院,南昌330038

出　　处：《无机材料学报》2021年第7期779-784,共6页Journal of Inorganic Materials

基　　金：National Natural Science Foundation of China(11974155)。

摘　　要：PdSe_(2)薄膜主要通过机械剥离法和气相沉积法制得,本研究采用一种简单有效的可在SiO_(2)/Si衬底上制备PdSe_(2)薄膜的方法。通过高真空磁控溅射技术在SiO_(2)/Si衬底上沉积一层Pd金属薄膜,将Pd金属薄膜与Se粉封在高真空的石英管中并在一定的温度下进行硒化,获得PdSe_(2)薄膜。根据截面高分辨透射电镜(HRTEM)照片可知PdSe_(2)薄膜的平均厚度约为30 nm。进一步研究硒化温度对PdSe_(2)薄膜电输运性能的影响,当硒化温度为300℃时,所制得的PdSe_(2)薄膜的体空穴浓度约为1×10^(18)cm^(–3),具有最大的室温迁移率和室温磁阻,分别为48.5cm^(2)·V^(-1)·s^(-1)和12%(B=9T)。值得注意的是,本实验中通过真空硒化法获得的薄膜空穴迁移率大于通过机械剥离法制得的p型PdSe_(2)薄膜。随着硒化温度从300℃逐渐升高,由于Se元素容易挥发,Pd薄膜的硒化程度逐渐减小,导致薄膜硒含量、迁移率和磁电阻降低。本研究表明:真空硒化法是一种简单有效地制备PdSe_(2)薄膜的方法,在贵金属硫族化合物的大面积制备及多功能电子器件的设计中具有潜在的应用价值。At present,the approaches to fabricate PdSe_(2) thin films mainly focus on mechanical exfoliation and chemical vapor deposition.In this study,we report a simple and efficient method to fabricate PdSe_(2) thin films on SiO_(2)/Si substrates.Firstly,a Pd metal layer was deposited on a SiO_(2)/Si substrate using magnetron sputtering.Then the PdSe_(2) thin film was obtained through selenization of the Pd layer at certain temperatures in a vacuum quartz ampule containing Se powder.According to the cross-sectional high-resolution transmission electron microscopy(HRTEM)image,the as-grown PdSe_(2) thin film has an average thickness of about 30 nm.The correlation between selenization temperature and electronic transport properties of PdSe_(2) thin films was investigated.PdSe_(2)thin films with a hole carrier concentration of~10^(18)cm^(–3) and a mobility of~48.5 cm^(2)·V^(-1)·s^(-1) are realized at a low selenization temperature of 300℃.It is worth noting that the mobility obtained by the vacuum selenization is superior to that of the p-type PdSe_(2) thin films fabricated by mechanical exfoliation from bulk PdSe_(2)single crystals.In addition,a relatively large room-temperature magnetoresistance(MR)of 12%is achieved for the PdSe_(2) thin films selenized at 300℃.With the increase in the selenization temperature from 300℃,mobility and magnetoresistance decrease due to the evaporation of Se element at high temperatures.This work demonstrates that present one-step selenization process is a facile and efficient approach to synthesize PdSe_(2) films,which could actually be used to prepare PdSe_(2) films in a large scale and may have potential applications for next-generation electronic and magneto-electronic devices.

关 键 词：贵金属硫族化合物 硒化 电输运性能 磁阻 

分 类 号：TB34[一般工业技术—材料科学与工程]