非晶Si/SiO_2超晶格结构的交流电致发光  

ACEL from Si/SiO_2 Superlattices

作　　者：孙甲明[1,2] 钟国柱 范希武[1,2] 

机构地区：[1]中国科学院激发态物理开放研究实验室 [2]中国科学院长春物理研究所,吉林长春130021

出　　处：《发光学报》2000年第1期24-28,共5页Chinese Journal of Luminescence

基　　金：国家高技术"863"材料委员会资助;国家自然科学重大基金资助项目!(批准号 698962 60 )

摘　　要：设计并用磁控溅射方法制备了非晶 Si/Si O2 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 Si O2 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 Si O2 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。通过透射电镜的照片可以看出 Si O2 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。透射光谱表明 ,光学吸收边随 Si层厚度的减小向短波方向移动 ;从退火前和退火后样品的喇曼光谱的变化可判断硅量子点的存在及其尺寸。利用双绝缘层的交流电致发光器件结构 ,首次获得非晶 Si/Si O2 超晶格的蓝绿色电致发光 ,在发射光谱中存在几个分立的发光谱带 ,随 Si层厚度的减小 ,短波发光谱带的相对强度增加。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.

关 键 词：超晶格 电致发光 硅量子点 

分 类 号：O472.3[理学—半导体物理] TN304.12[理学—物理]