| CPC H01L 23/544 (2013.01) [G03F 1/42 (2013.01); H01L 2223/54426 (2013.01)] | 20 Claims |

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1. An overlay metrology mark for determining an overlay error between two successive layers of a substrate, the overlay metrology mark comprising:
a first structural layer comprising a target feature; and
a second structural layer deposited over the first structural layer, wherein the second structural layer comprises:
a first axis;
a second axis crossing the first axis, wherein the target feature of the first structural layer is disposed at an intersection of the first axis and the second axis of the second structural layer;
a first alignment feature arranged on and aligned with the first axis; and
a second alignment feature arranged on and aligned with the second axis,
wherein the first alignment feature and the second alignment feature are in pairs;
wherein a relative displacement between the first structural layer and the second structural layer is determined via a position of the first axis of the second structural layer relative to the target feature of the first structural layer and a position of the second axis of the second structural layer relative to the target feature of the first structural layer.
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