Fine-dimension masks and related processes

A method of forming a mask for deposition of electrically conductive materials in a desired pattern on areas of a substrate comprising:

• providing a masking layer comprising a material, wherein said material of said masking layer comprises a metal selected from the group consisting of molybdenum, tungsten, niobium, stainless steel, alloys and combinations thereof;
• etching said masking layer within a first etch bath using an etchant to form at least one opening within said masking layer that represents said pattern on areas of said substrate whereby said material and said etchant react to form a byproduct within said first etch bath, said at least one opening being of a significantly reduced size;
• and
• during said etching, simultaneously monitoring and controlling activity of said etchant while monitoring and controlling a concentration of said byproduct within said first etch bath so as to control etching of said at least one opening in said masking layer to form said mask.

A method of forming a mask for deposition of electrically conductive materials in a desired pattern on areas of a substrate comprising:

• providing a molybdenum masking layer;
• providing a patterned first and a patterned second resist layer respectively over a first surface and a second surface of said molybdenum masking layer, said patterned first and second resist layers each having a plurality of openings therein of significantly reduced geometrical dimensions;
• etching said molybdenum masking layer having said patterned first and second resist layers thereon in a first etch bath using an etchant whereby a byproduct is formed between said molybdenum masking layer and said etchant;
• and
• during said etching, monitoring and controlling concentrations of said byproduct within said first etch bath while simultaneously monitoring and controlling activity of said etchant to regenerate said first etch bath in-situ to transfer said plurality of openings of significantly reduced geometrical dimensions into said molybdenum masking layer, said plurality of openings of significantly reduced geometrical dimensions in said molybdenum masking layer representing said pattern on areas of said substrate to form said mask.