Photoresponse Properties of a High-Speed Organic Photodetector Based on Copper–Phthalocyanine Under Red Light Illumination

Abstract

For this letter, carrier generation and charge transfer characteristics in an organic photodetector under forward and reverse bias conditions were analyzed. For the forward bias condition, holes are dominantly injected into the highest occupied molecular orbital states of copper-phthalocyanine from an indium tin-oxide electrode and flow into the Au electrode. However, under a reverse bias condition, the photocurrent is generated at the hetero interface and removed by both electrodes. A cutoff frequency of 70 MHz was observed under a reverse bias of 7V and clear response pulses at 100 MHz were observed using a sinusoidally modulated laser (lambda=650 nm)