Verification of transient RIC in polyethylene using numerical methods

Abstract

Current transients in radiation induced conductivity (RIC) of low-density polyethylene (I.DPE) exposed to 17 ns bremsstrahlung pulses were studied. Three niodcls of the R I C rclnxation, to 30 ps aftcr the pulse, havc been tested numerically. Strong influencc of the measuring circuit on the cxpcrimental rcwlts was taken into consideralion. Verification shows that thc RlC relaxation imncdiately aftcr the excitation consisb of the combination of at lcast fwo exponential components with markedly different relaxation times. This supporh our thesis, that the charge transport in LDPE during the 30 p s period after thc l~c excitation by means of brcmsstrahlung is occurring in the canduction band as a shallow-trap-limited, nondispersive current. 1070-9878101 $3.00 0 2000 IEEE