Electrical Properties of Polyethylene Single Crystals

Abstract

The currents through polyethylene single crystals have been measured as functions of voltage and temperature between 200°K and 400°K. The negative resistance phenomena were sometimes observed when thin wire electrodes were used for measuring the current through polyethylene single crystals of 70–300 Å thickness, but their behaviors were different from those described by Roggen. In the case of vacuum evaporated electrodes, however, such phenomenon was not observed. Similar measurements have been done with polyethylene thin films formed by vacuum evaporation. In this case, the negative resistance similar to that described by Hickmott was sometimes observed. Changes of specific resistance were closely related with the change of crystal thickness in thinner crystals, and the electron transport mechanism was discussed quantitatively with simple theoretical expressions of tunneling effect and Schottky emission.