Substrate for production of photomask, e.g. for integrated circuit production, has alignment markers formed from material of structured conductive layer and kept at specified potential by conductive connecting lines

摘要

A substrate (1) has a zone (91) of a structured conductive layer (3) on the substrate surface (10), together with alignment markers (7) to determine the position of the structured layer in relation to a reference potion, in which the markers are formed from the material of the conductive layer and the substrate also has a connecting line (93a-d) formed of conductive material, which connects with the markers and is used to maintain the markers at a specified potential. An independent claim is included for the production of a photomask by: (a) preparing a masking substrate; (b) preparing a first layer to be structured; (c) preparing a second layer to be structured (from conductive material) on the first layer; (d) preparing a first resist layer on the second layer to be structured; (e) structuring the first resist layer; (f) transferring the pattern formed in the first resist layer into the second layer and first layer to be structured; (g) applying a second resist layer; (h) structuring the second resist layer; and (i) transferring the resist pattern obtained into the second layer to be structured. Alignment markers are defined by structuring stage (e) to determine the relative position of the structured zone thus formed in relation to a reference position and these markers are etched into the second layer to be structured. Connecting lines (93a-d) connected with the alignment markers are formed to keep the markers at a specified potential.