固态阴极射线器件复合加速层的研究

Study of Complex Accelerating Layer in SSCL

固态阴极射线器件的加速层,是提高固态阴极射线性能的重要部分,它能够加大电子能量,倍增电子数量。其中增加注入电子从而提高过热电子的数量,是提高固态阴极射线器件性能的关键。为此,文章尝试将加速层复合,兼顾加速与电子注入性能。首先将SiO2,ZnS和ZnO分别与有机聚合物MEH-PPV组合,确定较适合的复合加速层的组合:SiO2/ZnS和ZnO/SiO2。然后将这两种复合加速层的性能对比,发现SiO2/ZnS的性能更优越,因为电子注入性能ZnS和ZnO相当,而电子加速倍增性能ZnS明显优于ZnO,其中SiO2为主要的加速层,而ZnS起到降低注入势垒变成阶梯势垒的作用。最后又将复合加速层结构的固态阴极射线器件和传统的SiO2夹层固态阴极射线器件对比,发现这种复合加速层结构,尤其在高场下,可提高固态阴极射线的初电子源和过热电子的数目,从而提高其发光效率具有促进作用。

Solid state cathode luminescence （SSCL） is a bran-new excitation mode. In the device, the inorganic semiconductor is used for electron acceleration. After acceleration the energy of electrons may be raised up so high that these hot electrons have enough energy to induce luminescence in the visible region by impact excitation. It is a new development and application of the traditional CRT theory in solid organic/inorganic electroluminescence device, and it is a new method to improve the EL efficiency. a new phenomenon of co-existence of different mechanisms of excitations in addition to these kinds of excitations. It is very important that all these effects are additive, amplifying or compensatory and reinforce the luminescence intensity and make the spectrum of luminescence wider. The accelerating layer of SSCL is the important part of improving the performance of SSCL devices, in which electrons can be accelerated to hot electrons with high energy and obtain electron multiplication. It is the key to improving the performance of SSCL devices, enhancing injecting electrons to increase hot electrons. So we prepared the complex accelerating layer with SiO2, ZnS and ZnO, giving attention to acceleration and injecting property. Firstly, we respectively prepared the devices with the polymer MEH-PPV and SiO2, and ZnS, and ZnO, and found that SiO2/ZnS and ZnO/SiO2 are better. And then contrasting them, we found SiO2/ZnS is better. It’s because that ZnS and ZnO are similar in injecting property, but ZnS is evidently better than ZnO in electron multiplication. SiO2 is the primary accelerating layer, and ZnS can lower the voltage barrier by ladder voltage barrier. Finally, we found that this complex accelerating layer, especially in high electric field, can increase the efficiency of SSCL devices by increasing initial electrons and hot electrons.