标题：Polarization Effect of Free Carriers in ZnO Single Crystal
作者：Cheng, Pengfei; Song, Jiang; Li, Shengtao; Li, Jianying; Wang, Chunming
作者机构：[Cheng, Pengfei; Song, Jiang] Xian Polytech Univ, Sch Sci, Xian 710048, Peoples R China.; [Li, Shengtao; Li, Jianying] Xi An Jiao Tong Univ, State K 更多
会议名称：2015 IEEE 11th International Conference on the Properties and Applications of Dielectric Materials (ICPADM)
会议日期：JUL 19-22, 2015
来源：2015 IEEE 11TH INTERNATIONAL CONFERENCE ON THE PROPERTIES AND APPLICATIONS OF DIELECTRIC MATERIALS
关键词：ZnO; polarization; conduction; carriers
摘要：Considering the response of free charges to high frequency alternating current ( AC) electric field and multiemission and capture processes of weakly bound charges, dielectric relaxation effect of free carriers are proposed in this paper. According to this model, free charges and bound charges are regarded as the same except for the difference in transport distance, which is defined by the frequency of applied AC electric field. Therefore conduction process of free charges and dielectric relaxation process of weakly bound charges in traditional dielectric theories are believed in this new model to originate from the same micro-mechanism of charge transport. In order to verify the validity of this model, dielectric properties of ZnO single crystal were measured by Novocontrol wide band dielectric spectrometer in temperature range from -120 to 30 degrees C and frequency range from 1 to 10(7)Hz. The relationship between electronic trap relaxation and dielectric relaxation effect of conduction process are discussed in detail. It was found that dielectric abnormity at low frequency and high frequency originates from conduction process of free carriers in grain and electronic trap relaxation at depletion layer respectively, both of which originate from the same micro-mechanism of electronic transport bound by intrinsic point defect. The paper offers a completely new way to understand and investigate dielectric relaxation phenomena.