1. In a method of fabricating an integrated circuit structure having a thin metal layer deposited on an insulating layer or substrate, the metal layer being formed of a metal which forms a native oxide coating on its surface, the steps of planarizing the metal layer comprising: forming the metal layer without an oxide coating; forming a passivating and antireflection coating on the unoxidized metal layer, the coating having a thickness substantially less than the metal layer; heating the coated metal layer to momentarily melt the layer for a time sufficient to substantially eliminate topographic variations of less than a preselected spatial period to produce a flat surface on the metal layer without reacting or alloying the metal layer with the insulating layer or substrate, the planarizing occurring prior to patterning the layer.