Bipolar transport and charge-carrier generation in polymethylphenylsilane thin films containing diphenoquinone

Bipolar transient transport in polymethylphenylsilane (PMPS) thin films containing 3,5-dimethyl-3′,5′-di-tert-butyl-4,4′-diphenoquinone (MBDQ) has been studied with the standard time-of-flight experiment. It is found that with increasing MBDQ concentration the electron drift mobility is observable above 30 wt % MBDQ addition (5.0×10−7 cm2/V s at 40 wt % MBDQ addition) and the hole drift mobility is unchanged (∼1.0×10−4 cm2/V s) for 0–40 wt % MBDQ addition. It is also found that the photocarrier generation efficiency is increased by an order of magnitude over pristine PMPS for 30–40 wt % MBDQ addition. These results demonstrate that MBDQ/PMPS composites are an approach to improving photoelectric properties of bipolar polymeric composites.