Reduced temperature contact/via filling

An integrated circuit fabrication method for filling a high-aspect-ratio via with a metal or alloy, comprising the steps of:

• providing a dielectric having a via therein;
• depositing a flow temperature lowering layer of material capable of diffusing into said metal or alloy over said dielectric and within said via and along the sidewalls of said via to lower the melting temperature of said metal or alloy when combined with said metal or alloy;
• disposing a layer of said metal or alloy over and in contact with said layer of material capable of diffusing into said metal or alloy, said layer of metal or alloy extending over said via;
• heating the metal or alloy while the metal or alloy is disposed over and in contact with the layer of a material capable of diffusing into a metal or alloy to lower the flow temperature of the metal or alloy to a temperature below the normal flow temperature of said metal or alloy, said temperature being sufficiently high to cause said material capable of diffusing into said metal or alloy to combine with said metal or alloy to lower the flow temperature of said metal or alloy to a temperature at or below the flow temperature of the combined metal or alloy and material capable of diffusing into a metal or alloy to cause said metal or alloy to flow;
• and
• filling said via with said metal or alloy.