Abstract

This review evaluates how carbon material selection, fabrication, and multiscale heat transport jointly determine the performance of carbon-based microheaters, with emphasis on graphene, carbon nanotubes (CNTs), amorphous carbon, functionalized carbon fibers, and selected transferable carbon nanostructures. A structured narrative synthesis of 70 Scopus-indexed references spanning 2003-2026 distinguishes direct microheater demonstrations from supporting material, modelling, and adjacent-transfer evidence. Direct evidence shows that graphene and CNT heaters enable rapid, low-power heating and mechanically compliant architectures, while printed or laser-written and functionalized carbon systems broaden flexible and structural applications. Recent process advances include multizone chemical vapor deposition, laser writing, and standardized printed-heater assessment; adjacent evidence on carbon-dot encapsulation and interface engineering is treated as transferable rather than as direct heater performance. Persistent gaps are temperature uniformity, reproducible doping and functionalization, wafer-scale process consistency, and experimentally validated multiscale models. The review contributes an integrated material-fabrication-transport-application framework and an evidence-aware roadmap for future carbon-based microheater design.