He离子注入ZnO中缺陷形成的慢正电子束研究  

Vacancy-type defects induced by He-implantation in ZnO studied by a slow positron beam

作　　者：陈志权[1] 河裾厚男 

机构地区：[1]武汉大学物理系,武汉430072 [2]日本原子力研究所,日本群马3701292

出　　处：《物理学报》2006年第8期4353-4357,共5页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:10375043;10075037)资助的课题.~~

摘　　要：在ZnO单晶样品中注入了能量为20—100keV、总剂量为4.4×1015cm-2的He离子.利用基于慢正电子束的多普勒展宽测量研究了离子注入产生的缺陷.结果表明,He离子注入ZnO产生了双空位或更大的空位团.在400℃以下退火后,He开始填充到这些空位团里面,造成空位团的有效体积减少.经过400℃以上升温退火后,这些空位团的尺寸开始增大,但由于有少量的He仍然占据在空位团内,因此直到800℃这些空位团仍保持稳定.高于800℃退火后,由于He的脱附,留下的空位团很快回复,在1000℃下得到完全消除.ZnO single crystals were implanted with He ions of energy of 20--100 keV. The total implantation dose was 4.4×10^15 cm^-2. Doppler broadening of positron annihilation spectra were measured using a slow positron beam to study the implantationinduced defects. The results suggest that after implantation, divacancies or larger vacancy clusters are produced. After annealing below 400℃, He impurity begins to occupy the vacancy clusters. Upon further annealing above 400℃, the vacancy clusters grow in size. At annealing temperature of above 800℃, He atom is released from the vacancy clusters, and the vacancies begin to recover and are annealed out at 1000℃.

关 键 词：慢正电子束 ZNO 离子注入 缺陷 

分 类 号：O782[理学—晶体学]