氧、硼、磷掺杂对氢化非晶硅中铒1.54μm发光的作用

Influence of O, B, P on 1.54μm Luminescence of Erbium doped Hydrogenated Amorphous Silicon

利用等离子体增强化学气相淀积 (PECVD)技术生长氧、硼、磷掺杂的氢化非晶硅薄膜。在室温下注入铒离子后研究三种掺杂元素对铒离子发光的作用。室温下观察到很强的光致发光现象。氧的引入并且和铒离子形成发光中心 ,提高了铒离子的发光强度。退火实验表明氧、硼、磷的掺杂补偿了材料中的缺陷 ,提高了氢的逃逸温度 ,改善材料的热稳定性 ,使材料的退火温度因掺杂元素的加入而提高 ,铒的发光得到增强。讨论了铒离子的发光机制。

Luminescence of Er in hydrogenated amorphous silicon film is promising for its potential application in optoelectronics. We investigated the influence of some light elements on the luminescence of Er in silicon based materials. O, B, P doped hydrogenated amorphous silicon films are fabricated via plasma enhanced chemical vapor deposition technique. XPS analysis indicated the ratio of Si and O contents in the film is 1∶1. After room temperature erbium implantation and rapid thermal annealing in N 2 ambient,photoluminescence (PL) of Er was measured. At room temperature strong PL of 1.54μm peak was observed. Oxygen has a great enhancement function on Er photoluminescence and B or P co doped with O further enhances PL intensity of Er. Rapid thermal annealing experiments indicated that the incorporation of three elements compensated the defects of the films, improved the thermal stability and enhanced the escaping temperature of H. The annealing temperature corresponding to the optimum PL intensity increased by 100℃, respectively, in three different kinds of samples. We attributed this phenomenon to the incorporation of O, B and P. The presence of oxygen with erbium formed optically active [Er O] complexes which greatly enhanced PL intensity. Also the excitation mechanism of Er was discussed.