摘要
研究了低能质子注入诱导的界面混合和快速热退火对量子点发光效率的影响,对其光致发光峰强进行了拟合计算.研究发现量子点的发光峰强度主要由载流子俘获时间和非辐射复合寿命决定.由于后退火处理能够部分的消除因质子注入造成的缺陷,量子点中非辐射复合中心浓度与注入剂量成亚线性关系;退火温度越高,非辐射复合中心被消除越多,亚线性程度越高.界面混合导致的俘获效率的增加和注入损伤引起的非辐射复合是相互竞争过程,存在一个临界的注入剂量NC,当注入剂量N小于NC,界面混合作用较为明显,量子点发光峰强随注入剂量增加而增强;当N大于NC时,质子注入引起了大量的非辐射复合中心,主要表现为注入损伤,量子点的发光峰强随注入剂量增加而迅速减弱.退火温度越高,NC越大.
Both the effects of the intermixing induced by the implantation dose and the annealing temperature on the light-emission efficiency of the quantum dots are studied. The intensities of photoluminesce (PL) are determined by the carriers capture time and non-radiative center lifetime. Annealing can partly eliminate the non-radiative center (NRC), so the NRC generation rate is a sublinear function of the proton dose (N). The carrier capture efficiency enhancement is induced by intermixing and degradation by the implantation damage which mutually compete, so there exists a critical implantation dose (NC). When N is less than NC, the intermixing is the main effect and the PL intensity increases with the implantation dose. On the other hand, when N is larger than NC, the implantation damage is so large that the intensity decreases with the dose. The higher the annealing temperature, the larger the NC becomes.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2005年第6期2904-2909,共6页
Acta Physica Sinica
基金
国家自然科学基金创新群体(批准号:60221502)
国家自然科学重点基金项目(批准号:10234040)
国家自然科学基金(批准号:60476040)
上海市科学技术委员会重点项目(批准号:02DJ14066)
上海市信息化专项资金项目(批准号:2003010)
国家重点基础研究资助项目(批准号:2
