InAs自组装量子点GaAs肖特基二极管中的电流输运特性  

CURRENT TRANSPORT PROPERTIES OF GaAs SCHOTTKY DIODE CONTAINING InAs SELF-ASSEMBLED QUANTUM DOTS

作　　者：李宏伟[1] 王太宏[1] 

机构地区：[1]中国科学院物理研究所,北京100080

出　　处：《物理学报》2001年第2期262-267,共6页Acta Physica Sinica

基　　金：国家自然科学基金! (批准号 :6 992 5 410和 1990 40 15 )资助的课题

摘　　要：设计了含有InAs自组装量子点 (SAQDs)的新型金属 半导体 金属隧穿结构 ,研究了其直流输运特性 ,观察到了电流迟滞回路现象 .这种回路现象是由于紧邻金属肖特基接触的量子点充电和放电引起的 ,也可以说是由外加电压控制的量子点的单电子过程引起的 .分析了量子点总体的充放电特性 ,量子点中电子在高电场下隧穿出量子点的概率变化决定了量子点的放电过程 ,而充电过程是由流过量子点层的二极管正向电流决定 .理论拟合结果显示充电过程主要由于量子点基态能级俘获电子照成的 ,激发态对量子点充放电过程只有微弱影响 .We have designed a new type metal\|semiconductor\|metal structure with InAs self\|assembled quantum dots. Hystereses loops were observed in DC current transport. With quantum dots(QDs) directly embedded beneath the GaAs\|metal interface, the charge and discharge of electrons in the dots modulate the current to form hysteresis. For a single quantum dot, the charge and discharge can be thought as single\|electron processes controlled by applied voltage. In this paper we analyzed the characteristics of charging and discharging processes for the ensemble of QDs as a whole. The discharging process was dominated by the change of tunneling rate with gate voltage. The charging process was controlled by forward current flowing though the diode. The calculated results indicate that the electrons trapped to the ground states of QDs give rise to charging effect. The excited states capture fewer electrons and influence the charging effect weakly.

关 键 词：迟滞现象 自组装量子点 砷化铟 砷化镓 肖特基二极管 电流输运特性 

分 类 号：O472[理学—半导体物理]