Method for producing refractory metal gate electrode

A method for producing a Schottky junction type refractory metal gate electrode comprising:

• coating a semiconductor surface with a silicon oxide film and forming an aperture in said silicon oxide film;
• forming a refractory metal film comprising WSiN on said silicon oxide film including the aperture;
• forming and patterning an Au film into a pattern on said WSiN film using a photoresist mask;
• etching said WSiN film into a configuration after forming and patterning said Au film;
• exposing said Au film with an organic solvent that disolves the photoresist mask and covering said Au film with a film of material that does not produce a reduction reaction upon contact with an HF solution;
• etching and removing said silicon oxide film with an HF solution;
• and
• removing said film of material that does not produce a reduction reaction with the HF solution with the organic solvent.

A method for producing a Schottky junction type refractory metal gate electrode comprising:

• coating a semiconductor surface with a silicon oxide film and forming an aperture in said silicon oxide film;
• forming a refractory metal gate film comprising WSiN on said silicon oxide film including the aperture;
• forming an Au film in a pattern on said WSiN film and forming a cap layer of a conductive metal that does not thermally react with Au and does not produce a reduction reaction upon contact with an HF solution;
• etching said WSiN film into a configuration;
• and
• etching and removing said silicon oxide film with the HF solution.

A method for producing a Schottky junction type refractory metal gate electrode having a configuration comprising:

• forming a patterning mask layer that is soluble in a solution including hydrogen ions and that has an aperture on a semiconductor substrate;
• forming a gate metal layer having an ionization potential larger than that of hydrogen on all of said patterning mask layer;
• before patterning said gate metal layer, covering part of an upper surface of said gate metal layer with a film that does not produce a reduction reaction with the solution including hydrogen ions, leaving part of said gate metal layer opposite the aperture exposed;
• depositing a second metal layer on said gate metal layer where said gate metal layer is exposed;
• uncovering the upper surface of said gate metal layer not covered by said second metal layer and removing the parts of said gate metal layer thus uncovered, thereby exposing part of said patterning mask layer and patterning said gate metal layer, leaving a gate electrode;
• covering said gate electrode with a second film that does not produce a reduction reaction with the solution including hydrogen ions;
• removing said patterning mask layer employing the solution including hydrogen ions;
• and
• removing said second film.