Passivation effect of Al∕LiF electrode on C60 diodes

The current–voltage characteristics, the temperature dependence of the dark conductivity, and the effect of oxygen exposure of C60 sandwich diodes are compared with Al and Al∕LiF as electrodes. It appears that a thin LiF interlayer can help to preserve the space-charge limited conduction in C60 diodes under exposure to air, by considerably suppressing the oxygen diffusion into the C60 film and reaction at the Al∕C60 interface.