Abstract: A thermally coupling electrically decoupling cooling device is described. The cooling device may be thermally disposed between a self-heating electrically conductive line and a semiconductor substrate to cool the line by transferring heat from the line to the substrate while blocking flow of current from the line to the substrate. The cooling device may contain a thermally conductive structure, such as a stack of vias and lines, to conduct heat away from the electrically conductive line, and a current blocking structure, such as a reverse biased diode or a capacitor, to block current flow into the substrate. Specific current blocking structures include a reverse biased diode containing an n-doped region and a p-doped region disposed between the thermally conductive structure and the substrate, and a capacitor containing a dielectric layer disposed between the thermally conductive structure and the semiconductor substrate.