摘要
利用射频磁控溅射方法 ,制成纳米 Si O2 层厚度一定而纳米 Si层厚度不同的纳米 (Si O2 / Si/ Si O2 ) / p- Si结构和纳米 (Si O2 ∶ Al/ Si/ Si O2 ∶ Al) / p- Si结构 ,用磁控溅射制备纳米 Si O2 ∶ Al时所用的 Si O2 / Al复合靶中的 Al的面积百分比为 1% .上述两种结构中 Si层厚度均为 1— 3nm ,间隔为 0 .2 nm .为了对比研究 ,还制备了 Si层厚度为零的样品 .这两种结构在 90 0℃氮气下退火 30 m in,正面蒸半透明 Au膜 ,背面蒸 Al作欧姆接触后 ,都在正向偏置下观察到电致发光 (EL ) .在一定的正向偏置下 ,EL强度和峰位以及电流都随 Si层厚度的增加而同步振荡 ,位相相同 .但掺 Al结构的发光强度普遍比不掺 Al结构强 .另外 ,这两种结构的 EL具体振荡特性有明显不同 .对这两种结构的电致发光的物理机制和 Si O2 中掺
The nanometer (SiO 2/Si/SiO 2)/p Si and nanometer (SiO 2∶Al/Si/SiO 2∶Al)/p Si structures with Si layers having twelve different thicknesses have been fabricated with the two target alternative magnetron sputtering technique. The ratio of Al to SiO 2 in the composite SiO 2/Al target is 1∶99. The thickness of Si layers in both the structures is from 1nm to 3nm with an interval of 0.2nm.Samples with Si layer of 0nm are also made for comparison.These two structures having been annealing at 900℃ in N 2 for 30min, thin Al films were deposited on the back of them to make good ohmic contacts,and then semitransparent Au films on the samples' front surfaces. At a forward bias, electroluminescence (EL) is observed from the Au/nanometer (SiO 2/Si/SiO 2)/p Si and Au/nanometer (SiO 2∶Al/Si/SiO 2∶Al)/p Si structures. It is found that the EL peak intensity, peak wavelength and current synchronously swing with the increasing Si layer thickness. But the EL intensity of Au/nanometer (SiO 2∶Al/Si/SiO 2∶Al)/p Si structure is stronger than that of Au/nanometer (SiO 2/Si/SiO 2)/p Si structure. And the swinging properties of the two structures are different. The EL mechanism of the two structures and the effects of doping Al into SiO 2 layers have been discussed.
基金
国家自然科学基金资助项目! (No.5 983 2 10 0 )&&
关键词
电致发光
纳米硅
二氧化硅
铝掺杂
electoluminescence
luminescence center
nanometer Si
