Abstract: Optimized 3-D graphene structures used to enhance thermal performance of the thermal systems such as vapor chambers are provided. The porosity of the wick/porous structure has a critical effect on the efficiency of a vapor chamber system. Graphene coating provides high thermal conductivity, and it has a high porous structure, which is favorable for vapor chamber devices.

Abstract: The present invention relates to a novel graphene sheet with modulated thickness comprising electrically conductive areas of an array of ridges constituting a grid structure on graphene surface wherein the ridging areas are integrally formed with the graphene sheet and are themselves made of graphene. The invention further relates to a method for producing the thickness modulated graphene material of above type by way of a special capping technique where the capping structure having an array of protrusions is involved so that the said capping would transfer its physical structure to the graphene surface to form areas with improved electrically conductivity and optical transparency.