Groupe de Physique des Matériaux (GPM), Université et INSA de Rouen, UMR CNRS 6634, Normandie Université, Av, de l'Université, BP 12, Saint Etienne du Rouvray, 76801, France.
Nanoscale Res Lett. 2013 Jan 21;8(1):39. doi: 10.1186/1556-276X-8-39.
: Photoluminescence spectroscopy and atom probe tomography were used to explore the optical activity and microstructure of Er3+-doped Si-rich SiO2 thin films fabricated by radio-frequency magnetron sputtering. The effect of post-fabrication annealing treatment on the properties of the films was investigated. The evolution of the nanoscale structure upon an annealing treatment was found to control the interrelation between the radiative recombination of the carriers via Si clusters and via 4f shell transitions in Er3+ ions. The most efficient 1.53-μm Er3+ photoluminescence was observed from the films submitted to low-temperature treatment ranging from 600°C to 900°C. An annealing treatment at 1,100°C, used often to form Si nanocrystallites, favors an intense emission in visible spectral range with the maximum peak at about 740 nm. Along with this, a drastic decrease of 1.53-μm Er3+ photoluminescence emission was detected. The atom probe results demonstrated that the clustering of Er3+ ions upon such high-temperature annealing treatment was the main reason. The diffusion parameters of Si and Er3+ ions as well as a chemical composition of different clusters were also obtained. The films annealed at 1,100°C contain pure spherical Si nanocrystallites, ErSi3O6 clusters, and free Er3+ ions embedded in SiO2 host. The mean size and the density of Si nanocrystallites were found to be 1.3± 0.3 nm and (3.1± 0.2)×1018 Si nanocrystallites·cm-3, respectively. The density of ErSi3O6 clusters was estimated to be (2.0± 0.2)×1018 clusters·cm-3, keeping about 30% of the total Er3+ amount. These Er-rich clusters had a mean radius of about 1.5 nm and demonstrated preferable formation in the vicinity of Si nanocrystallites.
采用光致发光光谱和原子探针层析技术研究了射频磁控溅射法制备的富硅二氧化硅薄膜中掺铒（Er3+）的光学活性和微观结构。研究了后处理退火对薄膜性能的影响。发现退火处理时纳米结构的演变控制了载流子通过 Si 团簇和 Er3+离子 4f 壳层跃迁的辐射复合之间的关系。从 600°C 到 900°C 的低温处理的薄膜中观察到最有效的 1.53μm 的 Er3+光致发光。在 1100°C 的退火处理，常用于形成 Si 纳米晶，有利于在可见光谱范围内产生强烈的发射，最大峰值约为 740nm。同时，检测到 1.53μm 的 Er3+光致发光发射急剧下降。原子探针结果表明，这种高温退火处理时 Er3+离子的团聚是主要原因。还获得了 Si 和 Er3+离子的扩散参数以及不同团簇的化学成分。在 1100°C 退火的薄膜中包含纯的球形 Si 纳米晶、ErSi3O6 团簇和嵌入 SiO2 基质中的游离 Er3+离子。Si 纳米晶的平均尺寸和密度分别为 1.3±0.3nm 和（3.1±0.2）×1018 Si 纳米晶·cm-3。估计 ErSi3O6 团簇的密度为（2.0±0.2）×1018 团簇·cm-3，保留了约 30%的总 Er3+量。这些富 Er 团簇的平均半径约为 1.5nm，并且在 Si 纳米晶附近优先形成。
