Patent ID: 7077974

Claim:
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; providing a first resist layer on a first surface of said masking layer; providing a second resist layer on a second surface of said masking layer; providing a first and a second glass master each having at least one opening therein of significantly reduced size; securing said first glass master to said first surface of said masking layer having said first resist layer; securing said second glass master to said second surface of said masking layer having said second resist layer, said first and second glass masters being substantially in alignment; transferring said at least one opening of significantly reduced size of each said first and second glass masters respectively into said first and second resist layers by exposing and developing said resist layers; 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.