Hardmask/barrier layer for dry etching chrome films and improving post develop resist profiles on photomasks

A photomask material comprising:

• a transparent glass substrate;
• a chrome-based layer directly over and contacting the transparent glass substrate;
• a metal layer comprising a material selected from the group consisting of tungsten, tungsten-silicon, tantalum, tantalum-silicon, and copper directly over and contacting the chrome-based layer;
• and
• a resist layer directly over and contacting the metal layer.

A method of manufacturing a photomask comprising:

• providing a transparent substrate;
• depositing an opaque layer directly over and contacting the transparent substrate;
• depositing a metal layer directly over and contacting the opaque layer;
• coating a resist layer over the metal layer;
• imaging the resist layer to form a resist mask pattern thereby exposing portions of the metal layer;
• etching the exposed portions of the metal layer using a first etchant that etches the metal layer faster than the underlying opaque layer to create a metal layer image;
• and
• transferring the metal layer image into underlying exposed portions of the opaque layer using a second etchant that etches the opaque layer faster than the metal layer to form a photomask in the opaque layer.