Estimation of carrier mobility using space charge measurement technique

The carrier mobility in a ethylene-vinylacetate copolymer (EVA) film was measured by a new technique. The time-dependent charge distribution in an EVA film was monitored by the pulsed-electroacoustic method when a pulse voltage was superposed on a DC bias voltage. A positive charge packet injected from the anode was observed soon after the pulse application, and traveled towards the cathode. It was suggested from the movement of the charge packet, that the mobility of the positive carrier at 0.1-0.6 MV/cm was in the order of 10^-9 cm²/Vs at room temperature. When the pulse voltage was very high, a charge packet appeared originating from the bulk, suggesting that the carrier dissociation takes place