稀土铒离子注入多孔硅的发光

稀土离子Er注入多孔硅中.在350keV能量,1×1012~1×1015/cm2剂量范围内,注入后的多孔硅仍保持明亮的可见光发射.退火后,在近红外区测到1.54μm附近Er3+的特征发射.其发射强度比硅单晶对照样品明显增强,实验表明这增强作用来源于多孔硅的表面发光层.电化学制备过程中在表面层中带入的O、C、F等多种杂质可能是Er3+发光增强的原因.

LUMINESCENCE OF RARE EARTH Er ION IMPLANTED POROUS SILICON

Rare earth ion Er+ has been implanted in porous silicon at 350 keV ion energy in 1×1012~1×1015cm2 dose range. After implantation the porous silicon still presented bright visible emission. After annealing, 1.54 μm characteristic emissions of Er3+ in PSi have been measured, and its intensity is much more intense than that of Si processed by same conditions. Further experiments show that enhancement of the Er3+ emission relates to the surface layer of porous silicon. There are a lot of impurity in the surface layer, such as O, C, F etc. Those impurities can form a variety of complex with Er which is favourable for decreasing segregation of Er during annealing, and increasing Er concentration. It is probable that the impurities introduced by electrochemical process give''rise to 1.54 μm luminescence enhancement.