Semiconductor element and manufacturing method thereof

A method for manufacturing a semiconductor element, comprising:

• a preparation step:
• preparing a semiconductor sample and placing the semiconductor sample on a stage of a cavity, wherein the semiconductor sample comprises a semiconductor substrate and a circuit pattern layer, the circuit pattern layer is on the semiconductor substrate, and a line width of the circuit pattern layer is less than 100 nm;
• a protective gas introduction step:
• vacuumizing the cavity, introducing a protective gas, and heating the stage to 250° C. to 480° C.;
• a reaction gas introduction step:
• stopping introducing the protective gas, introducing a reaction gas, and maintaining a temperature of the stage at 250° C. to 480° C., wherein the reaction gas comprises a hydrogen gas and benzene vapor;
• and
• a deposition step:
• reintroducing the protective gas, activating plasma, and maintaining the temperature of the stage at 250° C. to 480° C., so that the benzene vapor cracks to form a graphene layer on the circuit pattern layer, wherein a thickness of the graphene layer is 0.3 nm to 4.5 nm.