Space charge limited conduction with exponential trap distribution in reduced graphene oxide sheets

TL;DR

This study investigates the charge transport mechanisms in reduced graphene oxide sheets, revealing space charge limited conduction with exponential trap distribution and providing insights for optimizing device performance.

Contribution

It provides the first detailed analysis of trap distribution and charge conduction mechanisms in chemically reduced graphene oxide sheets.

Findings

Conduction is Ohmic at low bias and space charge limited at high bias and low temperature.

Estimated trap density is approximately 1.75x10^16 cm^-3.

Quantitative trap information aids in optimizing graphene device fabrication.

Abstract

We elucidate on the low mobility and charge traps of the chemically reduced graphene oxide (RGO) sheets by measuring and analyzing temperature dependent current-voltage characteristics. The RGO sheets were assembled between source and drain electrodes via dielectrophoresis. At low bias voltage the conduction is Ohmic while at high bias voltage and low temperatures the conduction becomes space charge limited with an exponential distribution of traps. We estimate an average trap density of 1.75x10^16 cm^-3. Quantitative information about charge traps will help develop optimization strategies of passivating defects in order to fabricate high quality solution processed graphene devices.