Low temperature catalytic growth graphene with V₂O₅ prepared with the oxidation method and its application in optoelectronic devices

Based on our previous research on the phase transition property of non-metallic vanadium oxide for low-temperature catalytic growth of graphene, we further propose that V thin films can be deposited by sputtering and then V 2 O 5 thin films can be prepared by oxidizing the V thin films at 400 °C in a rapid annealing furnace with oxygen, which has a better crystalline structure and surface than the V 2 O 5 thin films directly deposited by sputtering. The V 2 O 5 prepared by oxidation was used to catalyze the growth of graphene at 300 °C in a PECVD furnace. During the growth process, a 10-fold increase in the H 2 flow rate (200 sccm) was used to repair and eliminate the suspension bonds and defects of graphene, and the quality of graphene films was improved. Due to the high resistivity of V 2 O 5 at room temperature, V 2 O 5 can be directly used as the interlayer of the device, and the graphene-V 2 O 5 -Si (GVS) structure photodetector is proposed, which avoids the damage and impact of the transfer process and catalytic layer removal process in the conventional graphene device process. Additionally, because of the negative temperature coefficient of resistance (TCR) of vanadium oxide materials, the optical response of the GVS device is further extended to 1550 nm.