Multiple exposure method for photo-exposing photosensitive layers upon high step height topography substrate layers

A method for forming within an integrated circuit a patterned conductor layer upon a high step height topography substrate layer comprising:

• providing within an integrated circuit a high step height topography substrate layer having a blanket conductor layer formed thereupon, the blanket conductor layer having a blanket conformal photosensitive layer formed thereupon, the high step height topography substrate layer having a first region having a first step height separated from a third region having a third step height by a second region having a second step height, the second step height being intermediate to the first step height and the third step height;
• photo-exposing the blanket conformal photosensitive layer to form a first pattern upon the first region and the second region through use of a first reticle and a first photo-exposure condition, the first photo-exposure condition providing a first depth of focus suitable for at least the first region;
• photo-exposing the blanket conformal photosensitive layer to form a second pattern upon the second region and the third region through use of a second reticle and a second photo-exposure condition, the second photo-exposure condition providing a second depth of focus suitable for at least the third region, where the first pattern upon the second region and the second pattern upon the second region overlap, and where at least one of the first pattern upon the second region and the second pattern upon the second region has a serif formed therein, the serif providing improved resolution for the aggregate of the first pattern upon the second region and the second pattern upon the second region when both the first depth of focus and the second depth of focus are not suitable for the second region;
• developing then the photo-exposed blanket conformal photosensitive layer to form a patterned conformal photosensitive layer;
• and,
• etching the blanket conductor layer to form a patterned conductor layer using the patterned conformal photosensitive layer as an etch mask.