Li^＋对ZnO压敏陶瓷电性能和能带结构的影响  

Effect of Li^+ dopant on the electrical properties and energy band structure of ZnO varistor ceramics

作　　者：王发顶[1,2] 康雪雅[1] 

机构地区：[1]中国科学院新疆理化技术研究所,新疆乌鲁木齐830011 [2]中国科学院研究生院,北京100049

出　　处：《电子元件与材料》2009年第5期30-32,共3页Electronic Components And Materials

摘　　要：采用氧化物固相合成法,制备了掺Li2CO3的ZnO压敏陶瓷。研究了掺Li2CO3量对ZnO压敏陶瓷电性能和能带结构的影响。结果表明:当x(Li2CO3)从0增加到0.50%时,压敏电位梯度从529V/mm增大到2170V/mm。XRD测试发现,掺Li2CO3并未出现新相结构。晶界势垒高度揭示,ZnO晶粒尺寸的迅速减小是压敏电位梯度急剧增高的主要原因。Li+置换Zn2+,将会在禁带中价带的顶部形成附加的受主能级,使能带发生畸变。Li2CO3-doped ZnO varistor ceramics were prepared using oxide solid phase synthesis method. The effects of dopant amount on the electrical properties and energy band of ZnO varistor ceramics were studied. The results show that the voltage gradient of ZnO varistor ceramics increases from 529 V/mm to 2 170 V/mm with increasing x （Li2CO3） from 0 to 0.50. Through measuring the barrier height at grain boundaries, it is found that the sharp decrease of ZnO grain size mainly contributes to the significant increase of voltage gradient. XRD analysis indicates that there is no new phase present in the ZnO varistor ceramics when Li2CO3 is doped. With the substitution of Zn^2＋ by Li^＋, an additional acceptor level is formed in the band gap and nearby the top of valence band, inducing the distortion of energy band.

关 键 词：ZNO压敏陶瓷 Li+掺杂 压敏电位梯度 晶界势垒高度 能带结构 

分 类 号：TN379[电子电信—物理电子学] TN304.93