Metal-substituted transistor gates

A method for forming a transistor, comprising:

• forming a high-k gate dielectric on a substrate;
• forming a carbon structure on the gate dielectric;
• forming the source/drain regions for the transistor;
• and
• substituting a metal gate material for the carbon structure to provide the metal gate material on the high-k gate dielectric, including:
• forming a layer of the metal gate material on the carbon structure;
• and
• annealing the structure at a temperature below a eutectic temperature of the metal gate material and the carbon to encourage a substitution reaction to replace the carbon structure with the metal gate material such that a resulting metal gate is provided on the high-k dielectric.

A method for forming a transistor, comprising:

• forming a high-k gate dielectric on a substrate, including at least one of performing an atomic layer deposition process to form the high-k dielectric, performing an evaporated deposition process to form the high-k dielectric, and oxidizing a metal to form the high-k dielectric;
• forming a substitutable carbon structure on the gate dielectric;
• forming the source/drain regions for the transistor;
• and
• substituting a desired gate material for the substitutable carbon structure using a metal substitution reaction to provide the desired gate material on the gate dielectric.