A unique embossed carbon surface with regionally heterogeneous properties is constructed via carbonization of a polyacrylonitrile-b-poly(methyl methacrylate) (PAN-b-PMMA) block copolymer thin film precursor self-assembled under an external electric field. The PAN-b-PMMA block copolymer generates a thin surface having microdomains with alternating PAN-PMMA compositions different from that of the matrix when the microdomain alignment is induced under an electric field due to the difference in dielectric susceptibilities between two blocks.