电化学脉冲腐蚀制备均匀发光多孔硅

采用脉冲腐蚀和直流电化学腐蚀两种方法制备多孔硅,对这两种方法制备的多孔硅样品进行了扫描电镜和荧光光谱测量,发现脉冲腐蚀制备的多孔硅样品比直流腐蚀制备的多孔硅样品表面均匀、硅丝或者硅柱的尺寸较小、发光强度大,而且发光峰位有明显.的蓝移现象.同时我们还发现多孔硅样品的尺寸越小其能带越宽,由此得出多孔硅样品的发光现象符合量子限域解释的多孔硅的发光机制.

Preparation of Uniformly Luminescence Porous Silicon by Pulsed Electrochemical Etching Method

Porous Silicon(PS) was prepared by pulsed and DC electrochemical etching method under the same etching conditions.The scanning electron microscopy(SEM) and the photoluminescence(PL)observation showed that the porous Silicon surface prepared by pulsed etching was more uniform and the Silicon particles were smaller.The intensity of PL was enhanced.At the same time,we observed that the smaller the dimension of the PS,the broader energy gap of the PS.It concluded that the PL of our samples accorded with the mechanism of quantum confinement effect.