掺铒硅基材料发光的新途径

A NOVEL APPROACH OF PHOTOLUMINESCENCE FROM ERBIUM-DOPED SILICON-BASED MATERIALS

采用MEVVA源离子注入机将Si,Er先后掺杂到不同厚度的热氧化硅薄膜中 ,利用卢瑟福背散射 (RBS)能谱分析了掺杂层中Er原子的深度分布 ,Er的掺杂浓度为 10 2 1cm-3 量级 ;原子力显微镜 (AFM)形貌观测中发现有纳米晶Si镶嵌在注入层中 ;X射线光电子能谱 (XPS)的结果显示了不同厚度掺杂层中Er,Si,O含量的变化 .77K温度下 ,在退火态样品的近红外光致发光 (PL)谱中观察到了Er3+的 1 5 4μm特征发射 .Er3+作为孤立离子发光中心 ,其激活能主要来源于nc Si/SiO2 (c Si/SiO2 )界面处的载流子复合 ,再将能量转移给Er3+而产生发光 .

Silicon and erbium were duel-implanted into thermally oxidized SiO2/Si by MEVVA (Metal Vapor Vacuum Are) ion source implanter. After rapid thermal annealing,the 1.53 mum photoluminescence was observed at 77 K. RES results indicated that Er ions were mainly distributed near the surface of the samples,and the highest Er concentration reached 10(21) cm(-3). Nanometer crystalline silicon (nc-Si) was embedded in the implanted layer. X-ray photoelectron spectrum (XPS) showed the concentration variation of Er,Si and O in the implanted layer. Er3+ acted as an isolated ion luminescence center,and most excitation energy originated from the e-h combination at the interface of nc-Si/SiO2 (or c-Si/SiO2),then the energy transfered to Er3+ ions resulted in light emission of 1.54 mum.