MEH-PPV/SiO_2异质结发光机理和非晶SiO_2二次特性的研究

摘要

For electricity induced luminescence of thin film, the heterojunction luminescence devices were produced by compoun-ding the organic polymer of MEH-PPV and inorganic semiconductor SiO_2. Utilizing the super liner characteristic of SiO_2 as ac-celeration, multiplication and ionization, the solid-state cathocloluminescence was realized. The obvious feature of electrolumines-cence in the luminescence device with ITO/SiO_2/MEH-PPV/SiO_2/Al is that it has two spectral bands. In the electrolumines-cence spectra, the authors obtained both blue emission(403 nm)and excition luminescence(583 nm)of MEH-PPV and the intensi-ty of the long and short wave peak changing with the voltage. Only long wave peak is observed when the voltage is low and only short wave peak appears when the voltage is high. It is the typical feature that the solid-state cathodoluminescence has two spec-tral bands. It is a new light emission, which has new mechanism and is important for the luminescence. One of the important as-pects of the solid state cathodoluminescence theory is the super liner characteristic of SiO_2. In the present paper, the lumines-cence dynamics of solid-state cathodoluminescence, the super liner characteristic of SiO_2 in the higher electric field and the influ-ences of thickness on it were studied.%在薄膜电致发光中采用有机聚合物MEH-PPV和无机半导体SiO_2复合制成异质结发光器件,利用SiO_2的加速、倍增和离化的二次特性,实现了固态阴极射线发光.结构为ITO/SiO_2/MEH-PPV/SiO_2/Al的发光器件,其电致发光光谱的显著特征是有两个发光谱带.光谱中除了波长较长(峰值为583 nm)的MEH-PPV的激子发光谱外,还观察到了波长较短(峰值为403 nm)的蓝色发光谱,并且长短波的发光强度随着电压的不同而变化.电压较低时,只有长波光发射.当电压较高时,只有短波光存在.这种有两个谱带的发光是固态阴极射线发光的独特标志,它是一种全新的激发方式,引发出发光学中一些新而重要的问题.固态阴极射线发光理论的重要方面之一就足SiO_2的二次特性.文章研究了固态阴极射线发光动力学问题,高电场下SO_2二次特性及厚度对二次特性的影响.