多孔硅蓝光发射与发光机制

BLUE LIGHT EMISSION FROM POROUS SILICON AND PHOTOLUMINESCENCE MECHANISM

在制备出光致发光能量为２．７ｅＶ的发射蓝光多孔硅的基础上对它进行了较系统的研究：测量了它的光致发光时间分辨光谱，用傅里叶交换红外光谱分析了其表面吸附原子的局域振动模，研究了Ｙ射线辐照对其发光的影响，并与发红、黄光的多孔硅作了对比，通过空气中长期存放、激光和紫外线照射的方法，研究了光致发光峰能量为２．７ｅＶ的多孔硅发光稳定性．我们及其它文献中报道的多孔硅蓝光发射的实验结果与量子限制模型矛盾，但能用量子限制／发光中心模型解释．我们认为多孔硅的２．７ｅＶ发光是多孔硅中包裹纳米硅的ＳｉＯ＿ｘ层中某种特征发光中心引起的．

We have sysmatically studied the porous silicon (PS) that emits blue light with a peakenergy at 2. 7 eV; measuring its time-resoluted photoluminescence (PL) spectra and the localvibration mode absorption, and studying the Gamma ray lrradlatlon effect on its PL spectraand comparing the effect with that for the PS whICh emits red or yellow light. We have alsostudied the stabability of the blue light emission from PS after long term storage in air and ir radiation with laser and ultroviolet light. our experimental resuits and those in other refer ences for blue light emission from PS are contradictory with the quantum confinement mod el, but can be explained by the quantum confintjnlent/luminescence centers model. We consid er that the blue light emission originates from some characteristic luminescence centers in theSiO_x layer covering nanoscale silicon in PS.