▎ 摘　　要

NOVELTY - The biosensor has a lower dielectric layer (302) that is positioned on substrate (100). A bottom surface of lower dielectric layer is physically contacted with DNA containing fluid within fluid channel. A graphene layer (304) is arranged on lower dielectric layer. An upper dielectric layer (306) is arranged on graphene layer. A source region (402) is arranged on lower dielectric layer. A drain region (404) is arranged on lower dielectric layer. A transistor is defined by source region and drain region to detect resistance of single strand DNA contained within fluid. USE - Biosensor such as graphene biosensor used in life science, clinical diagnostics and medical research for sensing hybridization between complementary single strand DNA in micro array and binding of matched antibody-antigen pair. ADVANTAGE - The thin lower dielectric layer can be provided between the fluid in the flow path and the graphene layer, so that the sensitivity of the biosensor can be improved efficiently. DESCRIPTION OF DRAWING(S) - The drawing shows a cross-sectional view illustrating the method for forming graphene sensor. Substrate (100) Lower and upper dielectric layer (302,306) Graphene layer (304) Source region (402) Drain region (404)