Loading patent…
AssigneeInternational Business Machines Corporation
InventorsHartmut F. Kolbe, Frank A. Schwarzbach
Estimating the term…
The invention relates to a mask for imaging a pattern on a photoresist layer, with at least one alignment mark, to a method of making such a mask, and use of these masks for making semiconductor components. The masks made in accordance with the invention are obtained in such manner that in their production the patterns of adjacent chip fields are imaged to the effect that they overlap in their border lines containing the alignment marks. The process produces alignment marks representing the mean of at least two alignment marks of adjacent chip fields. By means of the above specified manufacturing process, the opto-mechanical imaging defects observed during mask production can be substantially eliminated. The masks as disclosed by the invention can be aligned in semiconductor processes with more precision than prior art masks.
Mask for imaging a pattern on a photoresist layer disposed on a semiconductor wafer having border lines separating chip fields, said mask including at least one alignment mark arranged in that mask area corresponding to said border lines on said semiconductor wafer, characterized in that the said at least one alignment mark represents the mean of at least two alignment marks of adjacent mask areas, said mean being the area formed by the one portion of adjacent alignment mark superimposed on a portion of at least one other adjacent alignment mark.
Method of making a mask for imaging a pattern on a photoresist layer with at least one alignment mask, characterized in that a reticle with the patterns of the respective chip field and of the alignment mark is periodically imaged with an n-fold reduction on a glass plate with a chromium and a photoresist layer, that the photoresist layer is developed, and the chromium layer is etched through the photoresist mask.
Dependencies are inferred from the claim text.