Process for forming cobalt and cobalt silicide materials in tungsten contact applications

A method for forming a cobalt silicide material on a substrate surface, comprising:

• exposing a substrate comprising a silicon-containing material disposed thereon to a wet etch process or a plasma clean process while removing oxides or contaminants disposed on the silicon-containing material, wherein the substrate is exposed to a hydrofluoric acid solution during the wet etch process or the substrate is exposed to a plasma formed from a pre-clean gas comprising nitrogen trifluoride during the plasma clean process;
• thereafter
• depositing a cobalt metal layer on the silicon-containing material by a chemical vapor deposition process within a first processing chamber coupled with a processing system;
• heating the substrate to form a first cobalt silicide layer comprising CoSi at the interface of the cobalt metal layer and the silicon-containing material during a first annealing process, wherein a portion of the cobalt metal layer reacts with the silicon-containing material to form the first cobalt silicide layer containing a surface of unreacted cobalt metal thereon;
• removing the unreacted cobalt metal from the substrate during an etch process;
• and
• converting the first cobalt silicide layer to a second cobalt silicide layer comprising CoSi2 by heating the substrate during a second annealing process.

A method for forming a cobalt silicide material on a substrate surface, comprising:

• exposing a substrate comprising a silicon-containing material disposed thereon to a wet etch process or a plasma clean process while removing oxides or contaminants disposed on the silicon-containing material, wherein the substrate is exposed to a hydrofluoric acid solution during the wet etch process or the substrate is exposed to a plasma formed from a pre-clean gas comprising nitrogen trifluoride during the plasma clean process;
• thereafter
• exposing the substrate to a hydrogen plasma during a pre-clean process;
• depositing a cobalt metal layer on the silicon-containing material by a chemical vapor deposition process within a first processing chamber coupled with a processing system;
• heating the substrate to a first temperature and forming a first cobalt silicide layer comprising CoSi at the interface of the cobalt metal layer and the silicon-containing material during a first annealing process, wherein a portion of the cobalt metal layer reacts with the silicon-containing material to form the first cobalt silicide layer containing a surface of unreacted cobalt metal thereon;
• transfer the substrate to a wet etch chamber and remove the unreacted cobalt metal from the substrate during an etch process;
• and
• heating the substrate to a second temperature and forming a second cobalt silicide layer comprising CoSi2 during a second annealing process, wherein the CoSi of the first cobalt silicide layer is converted to CoSi2 of the second cobalt silicide layer during the second annealing process, and the second temperature is greater than the first temperature.