非晶Si/SiO2超晶格结构的交流电致发光

设计并用磁控溅射方法制备了非晶Ｓｉ／ＳｉＯ２超晶格结构，以高纯多晶Ｓｉ为靶材，当以Ａｒ＋Ｏ２为溅射气氛时，得到ＳｉＯ２膜，仅以Ａｒ为气氛时，得到Ｓｉ膜。重复地开和关Ｏ２气，便交替地得到ＳｉＯ２和Ｓｉ膜。衬底在靶前往返平移，改变平移的速度或者改变溅射的功率，可以控制膜的厚度。通过透民镜的照片可以看出ＳｉＯ２和Ｓｉ膜具有均匀的周期结构，用低角Ｘ－射线反射谱表征了超晶格的周期结构和各层的厚度。透射光谱表

ACEL from Si/SiO2 Superlattices

Si/SiO 2 superlattice structure was designed and prepared by rf magnetron sputtering technique. The high pure polycrystal Si was taken as sputtering target. SiO 2 film was obtained by using Ar+O 2 as sputtering atmosphere; Si film was obtained by using Ar as sputtering atmosphere; Si/SiO 2 superlattice structure was prepared by shutting off O 2 or openning O 2 repeatedly. The thicknesses of Si and SiO 2 layers were controlled by sputtering power or velocity of moving substrate in front of target. The periodic structure of superlattice was demonstrated by TEM and low angle X ray reflection spectra. The optical transparence spectra showed that the optical absorption edge shifted to shorter wavelength when thickness of Si layer was decreased. Laser Ramman spectra of the samples before and after annealing gave the evidence of existence of Si quantum dots in Si layer and the size of Si quantum dots. Blue green ACEL from Si/SiO 2 superlattice with double insulating layers structure was obtained for the first time. There were several emission bands in EL spectrum. When the thickness of Si layer is decreased, the intensity of the shorter wavelength emission band increased quickly.