Highly Sensitive Photodetector Based on Transfer-Free 3-D Graphene on SiO2

• Published in: IEEE sensors journal 2024-03, Vol.24 (5), p.6038-6044
• Main Authors: Lee, Bom, Nasir, Tuqeer, Cho, Sooheon, Jung, Myeongjin, Kim, Bum Jun, Lee, Sang Hoon, Jang, Han Eol, Kang, Joohoon, Yu, Hak Ki, Choi, Jae-Young
• Format: Article
• Language: English
• Subjects: Copper; Electric potential; Electromagnetic absorption; Flakes (defects); Graphene; Metalorganic chemical vapor deposition; Optoelectronics; Organic chemistry; photodetector; Photodetectors; Photometers; Photovoltaic cells; Quantum efficiency; Recovery time; Silicon; Silicon dioxide; Silicon oxides; Silicon substrates; Solar cells; Substrates; Surface morphology; Three-dimensional displays; Touch screens; transfer-free; Ultrafast lasers; Voltage; wideband photosensor
• ISSN: 1530-437X; 1558-1748
• DOI: 10.1109/JSEN.2024.3349424

Graphene has exceptional optoelectronic and photonic capabilities for diverse applications in solar cells, ultrafast lasers, touch screens, and photodetectors. Here, we report a graphene photodetector synthesized directly on silicon oxide/silicon (SiO2/Si) substrates using the metal-organic chemical vapor deposition technique. The as-grown flake-like 3-D graphene has increased surface area with numerous edge defects originating from flake edges. Additionally, the light absorption in the heavily p-doped SiO2/Si substrate generates an additional photovoltage that effectively modulates the conductance of graphene, leading to high responsivity of ~114.64 A/W at a drain voltage of 15 V over a large bandwidth from visible to the near-infrared (IR) region with response and recovery time of ~7 ms. In particular, the graphene photodetector achieves an external quantum efficiency (EQE) of 21702.23% and detectivity of 1.24\times1011 Jones at a drain voltage of 15 V. This transfer-free and scalable method can lead to low-cost and highly efficient photodetectors.