中文摘要：

硅光子学中的关键问题是研制高效率的硅基光源，文章为此提出了一种实现硅基发光的方法。采用共溅射的方法在n＋型重掺杂硅衬底上制备了富硅氧化硅（SiO2∶Si）薄膜，然后用热扩散法进行了锰（Mn2＋）掺杂和光学活化。高分辨透射电镜观察表明薄膜中形成了3～5 nm的硅纳米晶体。该薄膜在紫外光照射下发射出明亮的绿光，光致发光谱峰位在524 nm（2.36 eV），一般认为这是来自Mn2＋能级4T1 →6A1基态跃迁的绿光辐射;其荧光寿命为0.8 ms。将该掺锰富硅二氧化硅（SiO2∶Si∶Mn2＋）做成电致发光结构，在低反偏电压下观察到近乎白色的电致发光（EL），光谱范围覆盖了400～800 nm。研究表明，该电致发光谱来源于薄膜中的Mn2＋以及氧化硅中的缺陷发光中心两者光谱的叠加;Mn2＋的发光是靠薄膜中的热电子来激发的;并由此探讨了薄膜中的硅纳米晶体在电致发光过程中的作用。

英文摘要：

Abstract Recently, a monolithic integration of optics and electronics in a single Si chip has attracted a great deal of attention due to its attractive application prospects： the potential for forming high speeded information processing and transmission, and inex- pensive and low power silicon chip. Developing high-efficiency silicon-based light sources is the main task in silicon photonies. In the present paper the authors explore a potential way for silicon-based light-emitting application. A Mn^2＋-activated silicon-rich silicon oxide （SiO2 ： Si ： Mn^2＋ ） film was prepared on the n＋-type silicon substrate using co-sputtering technique followed by doping and activation of Mn with a thermal diffusion method. High-resolution transmission electronic microscope study shows that the film is embedded with 3-5 nm silicon nanocrystals. Bright green photoluminescence （PL） from the film was observed under ultraviolet radiation and peaked at 524 nm （2. 36 eV）, the decay time of which is 0. 8 ms. It is generally believed that the green radiation originates from ^4T1→^6A1 transition in Mn^2＋. The PL excitation spectrum of the film, monitored at 524 nm, has a peak of 254 nm, similar to that of the Zn2SiO4 ： Mn film. It is believed that the strong 254 nm absorption is attributed to Mn^2＋ → Mn^3＋ ionization or d^5→d^4s transition. A very broad electroluminescence spectrum ranging from 400 to 800 nm, covering almost the whole visible band, was observed from the device made of the SiO2 ： Si ： Mn^2＋ film at low reverse biases. The threshold voltage of the device is as low as 5 V. Spectra of the device demonstrate that the electrolumineseence is attributed to Mn^2＋ and centers in the Si-rich SiO2 film. The authors interpret that Mn^2＋ excitation is mainly due to direct impact excitation of hot electrons, silicon nanocrystals in the SiO2 film help electrons tunnel from a silicon nanocrystal to an adjacent one, and are advantageous for generating hot electrons to excite Mn^2＋.