Effect of nano-SiO₂ films on the electron radiation induced conductivity of polyimide

Abstract

The radiation induced conductivity (RIC) behaviors in nano-SiO2 deposited polyimide (PI) were investigated using the in situ measurement technique. The results indicate that, by comparison with the case of virgin polyimide, the RIC in nano-SiO2 /polyimide shows low steady state values. Moreover, the steady state RIC is a power function of the dose rate with a power index of 0.659, lower than that of 0.76 in the virgin polyimide. The interfacial barrier and trapping effects are the main reasons for the change. Meanwhile, both of the interfacial effects also result in a unipolar carrier transportation mechanism in nano-SiO2 deposited PI from the dipolar one in the virgin PI. The mechanisms of the RIC behaviors are discussed in the paper.

Synthesis, Characterization and Thermal Properties of SiO₂/Pi Composite Film

“…After SiO 2 is added to the polyimide, the mechanical properties [1] , the multifunctional thermal and insulation characteristics [2] , the creep resistance [3] of the SiO 2 /PI composite films can be remarkably reinforced. SiO 2 could reduce specific heats and increase thermal conductivities [4] and the radiation induced conductivity [5] of the films. A lot of unsaturated dangling bonds, the large specific surface area and the high surface energy in the amorphous SiO 2 , can bring about dispersing easily SiO 2 to the polyimide and combining SiO 2 with the organic group.…”