Arrays of covalently immobilized and aligned graphene ribbons have been successfully prepared on silicon wafers. The effect of covalent modification on the electrical properties of the single-layer graphene was investigated. The effective electron field mobility of the constructed FETs, measured at 2700 cm2V(-1) s(-1), was higher than that for graphene film directly deposited on SiO2, possibly due to lower phonon scattering from the substrate surface, implying that the field effect mobilities may be enhanced with proper choice of substrates. The contact resistance between Cr electrodes and the single-layer graphene ribbon was determined to be 1.62 komega from the TLM structures.