Method for forming a multilayered metal network for bonding components of a high-density integrated circuit using a spin on glass layer

A method of forming a multilayered metal network for interconnecting components of a high-density integrated circuit, comprising forming on a substrate a lower metal layer including conductors having steep edges;

• applying a dielectric layer directly over said lower metal layer using chemical vapor deposition of silicon dioxide;
• spreading a layer of spin-on-glass in the form of a viscous suspension of silicon dioxide directly onto said lower metal layer;
• annealing the spin-on-glass suspension layer;
• forming vias through said spin-on-glass and dielectric layers to expose portions of said conductors of said lower metal layer by using a reactive plasma etching process which is controlled to flare the vias and provide the vias with a frusto-conical section;
• and applying directly over said spin-on-glass layer as upper metal layer, the upper metal layer being applied so as to cover the spin-on-glass layer and to fill the vias.