Low-frequency noise properties of metal-organic-metal ultraviolet sensors

For this study, the metal-organic-metal (MOM) ultraviolet (UV) sensors with organic 4,4′,4′′-tris[3-methylphenyl(phenyl)amino]triphenylamine (m-MTDATA) thin films of various thicknesses were fabricated successfully, and their low-frequency noise (LFN) characteristics were also analyzed. The findings revealed that the UV-to-visible rejection ratio of the fabricated 80-nm-thick m-MTDATA UV sensor was approximately 7.81 when biased at 5 V, with a cutoff at 220 nm. With an incident light wavelength of 220 nm and an applied bias of 5 V, the measured responsivity of the 80-nm-thick m-MTDATA UV sensor was found to be 2.84 × 10−4 A/W. Furthermore, a noise-equivalent power (NEP) of 9.8 × 10−11 W and a detectivity (D*) of 8.3 × 108 cm Hz0.5 W−1 can be achieved using the fabricated 80-nm-thick m-MTDATA UV sensor.