The cooling device, particularly for electronic components, such as microprocessors, consists of a substrate (1), which features a heat-inlet surface that is in thermal contact with an object (6) to be cooled and a heat-dissipation surface. The heat-dissipation surface has a defined structure, preferably in the form of continuous channels (2), and has a significantly larger surface area than the heat-inlet surface. At least the heat-inlet surface, but preferably also all or significant portions of the heat-dissipation surface are provided with a thin coating (3) made of heat-conductive material. Another improvement is obtained because the surface features a coating made of fine particles (21), e.g., made of metal or metal oxide, which further increases the surface area.