| United States Patent | 6,424,882 |
| Pierrat | July 23, 2002 |
The shape of chrome patterns on an optical pattern transfer tool are adjusted to get a desired shape on a wafer in the manufacture of semiconductor devices, wherein very small regions on a photoresist are defined and these regions are controlled with a high degree of accuracy. The optical pattern transfer tool has first and second planar surfaces lying in substantially parallel planes and a plurality of opaque regions overlying the first planar surface. First and second steps formed between and the first and second planar surfaces at first and second edges, respectively, define a width of the first planar surface. Each of the opaque regions are spaced from one another and offset from one another such that they are alternately aligned along a length of the first planar surface, such that one of the opaque regions is aligned with a portion of the first edge and the next one of the opaque regions along the length is aligned with a portion of the second edge. As a result of improving the process latitude of the wordline level in DRAMS, the size of the wordline over nonactive areas is reduced so that a maximum area is given for active areas for the bit contact and the container.
| Inventors: | Pierrat; Christophe (Boise, ID) |
| Assignee: | Micron Technology, Inc. (Boise, ID) |
| Appl. No.: | 768000 |
| Filed: | January 23, 2001 |
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