Patent ID: 8592107
Filing Date: 2013-11-26
Classification: G03F,H01L

Abstract:
1. An apparatus comprising an overlay mark, the overlay mark including: a first portion that includes a plurality of first features, each of the first features having a first dimension measured in a first direction and a second dimension measured in a second direction that is approximately perpendicular to the first direction, the second dimension being greater than the first dimension; and a second portion that includes a plurality of second features, each of the second features having a third dimension measured in the first direction and a fourth dimension measured in the second direction, the fourth dimension being less than the third dimension; wherein at least one of the second features is partially surrounded by the plurality of first features in both the first and second directions, and wherein the first and second portions are both disposed within a single layer, and wherein the first dimension and the fourth dimension are each approximately equal to a gate length of a transistor.