稀土元素Er掺杂提高WSe2纳米薄膜的光电特性  

Enhancement of Optoelectronic Properties of WSe2 Nanofilms by Rare Earth Element Er Doping

作　　者：朱静怡 丁馨 张晓渝 马锡英[1] Zhu Jingyi;Ding Xin;Zhang Xiaoyu;Ma Xiying(School of Physical Science and Technology,Suzhou University of Science and Technology,Suzhou 215009,China)

机构地区：[1]苏州科技大学物理科学与技术学院,江苏苏州215009

出　　处：《微纳电子技术》2020年第12期992-997,1027,共7页Micronanoelectronic Technology

基　　金：江苏省十三五重点学科资助项目(20168765);苏州科技大学科研基金资助项目(XKZ201609);江苏省研究生科研创新计划资助项目(KYCX18_2551)。

摘　　要：采用热蒸发法在Si片上沉积稀土元素Er掺杂的WSe2薄膜,研究了Er^3+掺杂对WSe2薄膜表面形貌、晶体结构﹑光致发光光谱、光吸收特性和电学特性的影响。研究发现薄膜在(004)晶面呈柱状择优生长,Er^3+掺杂不仅没有改变WSe2的晶体结构,还使薄膜结晶性显著增强,提高了光吸收特性,明显增加了光致发光强度。同时发现Er^3+掺杂WSe2薄膜的电子迁移率为未掺杂的4倍多。当光照强度由0增加到25 mW/cm^2时,Er^3+掺杂的WSe2/Si异质结的Ⅰ-Ⅴ曲线由整流特性逐步变成线性,相同偏压下光电流增加了约3倍,并且光电导灵敏度也明显增加。随着加热温度的升高,电导显著增大,电阻表现负温度系数。表明WSe2/Si异质结对温度和光强具有非常高的灵敏度,在高效率的温度传感器和光电探测器等方面有良好的应用前景。WSe2 films doped with rare earth element Er were deposited on Si wafer by thermal evaporation.The effects of Er^3+doping on surface morphology,crystal structure,photoluminescence spectra,optical absorption characteristics and electrical characteristics of WSe2 films were studied.The study shows that the films with columnar surface are preferentially grown on the(004)crystal plane.Er^3+doping does not change the crystal structure of WSe2,and significantly enhances the crystallinity of films,improves the optical absorption characteristics and significantly increases the photoluminescence intensity.It is found that the electron mobility of the Er^3+doped WSe2 films is more than 4 times that of the undoped films.When the light intensity increases from 0 to 25 mW/cm^2,theⅠ-Ⅴcurve of the Er^3+doped WSe2/Si heterojunction gradually changes from rectification characteristic to linear characteristic,the photocurrent increases by about 3 times under the same bias voltage,and photoconductive sensitivity also increases significantly.As the heating temperature increases,the conductance increases significantly,and the resistance exhibits a negative temperature coefficient.It is shown that the WSe2/Si heterojunction has very high sensitivity to temperature and light intensity,and has a good application prospect in high-efficiency temperature sensors and photoelectronic detectors.

关 键 词：硒化钨(WSe2) Er3+掺杂 纳米薄膜 热蒸发法 异质结 光电特性 

分 类 号：TN383[电子电信—物理电子学]