Thermal management at the nanoscale offers potential advancements in power-efficient geometrical design
however, both conduction- and convection-based structural optimization have yet to be fully investigated due to dimensional limitations. In this study, we analytically designed a structured configuration within a regime comparable to the mean free path of heat-transferring carriers. The optimally designed nanowire configuration, featuring aligned nanowires with narrow gaps (∼22 nm), was designed based on the analytic calculation. A tailored nanofabrication technique enabled a reliable geometrical parametric study, experimentally validating the proposed theoretical design. Finally, by engineering both conduction heat loss and air molecular interactions in convective heat loss at the nanoscale, we suggest an optimized heater for atmospheric conditions based on scaling factor-induced thermophysical properties, surpassing the efficiency of traditional film-based heaters.