离子注入氧化锌纳米晶体光致发光特性

摘要

A study of the effects of H+ and He+ implantation on the photoluminescence(PL) of ZnO nanocrystals is presented.This investigation is motivated by the need to further understand the effects of damage resulting from the implantation process on the luminescence response of the nanocrystals.Thin films of ZnO nanocrystals with diameters of either 4 nm or 9 nm were created on SiO2 substrates.The films were then implanted with H+ or He+ at room temperature and the resulting change in PL response due to the implantation was investigated. Implantation with He+ led to an increase in defect PL emission compared to the emission from as-grown nanocrystals,whereas the defect emission after H+ implantation was largely diminished indicating that H passivates the implantation damage.Comparing the near band edge(NBE) to defect emission ratio,the large (9 nm) nanocrystals showed an increase after H+ implantation and a decrease after He+ implantation.The NBE/defcct emission ratio for the small (4 nm) nanocrystals showed the same trends as the large nanocrystals,but the magnitude of the change after H+ implantation was considerably less.%为进一步了解离子注入过程对纳米晶体发光响应的损伤效果,研究了注入氢离子和氦离子对氧化锌纳米晶体光致发光(PL)特性的影响.首先在二氧化硅衬底上制备了直径为4 nm和9 nm的氧化锌纳米晶体薄膜,接着在室温下向生成的薄膜中注入氢离子和氦离子,并研究其PL响应变化.结果表明,与未注入离子的纳米晶体相比,注入氦离子导致缺陷PL发光增加,而当注入氢离子之后,缺陷发光大幅降低,表明氢原子对注入损伤有钝化作用.比较近谱带边沿(NBE)与缺陷发光之比发现,较大颗粒的纳米晶体其近谱带边沿与缺陷发光比在注入氢离子后增大,而在注入氦离子后降低.该规律同样适用于较小颗粒的纳米晶体,但其近谱带边沿与缺陷发光比在注入氢离子之后的增幅比大颗粒晶体的小得多.