▎ 摘　　要

NOVELTY - The method involves forming a patterned resist on or over a region of a dielectric-material-capped graphene layer structure and on sub-portions of exposed portions of a substrate to define contact portions adjacent to exposed edges. Ohmic contacts are formed in the contact portions. Dielectric material of the structure region is exposed by removing all resist material. A layer of the material is formed on and across the region of the layer structure, the ohmic contacts and an adjacent portion of the substrate, where the layer of material and/or another layer are an inorganic oxide. USE - Method for producing electronic device precursor i.e. Hall-effect sensor precursor. Can also be used for a transistors, LEDs, photovoltaic cells and diodes. ADVANTAGE - The method enables preventing highly sensitive graphene layer structure from contamination thereby avoiding loss in desirable electronic properties and improving electronic properties of the graphene in a final product. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for an electronic device precursor. DESCRIPTION OF DRAWING(S) - The drawing shows a flow diagram illustrating a method for producing electronic device precursor.