Temperature-dependent electrical characterization of a p-Si/BBL heterojunction p-n diode

A p-n heterojunction diode was fabricated via in-situ deposition of n-type poly[benzimidazobenzophenanthroline]-BBL thin films on p-doped silicon substrates. The diode was electrically characterized as a function of temperature in the range 150K < T < 370K. Current-voltage (I-V) tests showed asymmetrical curves, suggesting the formation of a p-n diode at the p-Si/BBL interface. Using the standard diode equation, the ideality parameter (n), rectification ratio (), and turn-on voltage () were calculated as a function of temperature. Preliminary analysis revealed that as the temperature decreased, n increased from 1.6 to 250, decreased from 10 to 1, and stayed relatively constant at ~2.6V. We discuss our results in terms of the charge mobility and the presence of charge traps at the p-Si/BBL interface.