International Business Machines Corporation

Faisal Azam

Helen Wang

Andrew Lu

Patricia Argandona

Method for measuring misalignment between at least two layers of an integrated circuit. The method includes applying a current between a plurality of probe members in a first layer, wherein a first probe member and a second probe member of the plurality of probe members are substantially aligned along a first axis and partially overlap an overlay target in a second layer, measuring a voltage across the plurality of probe members wherein at least a voltage across the first probe member and a third probe member disposed perpendicular to the first axis and a voltage across the second probe member and the third probe member are measured, and determining an amount of misalignment between the first layer and the second layer along at least one of the first axis and the second axis based on the measuring steps.

Systems and methods for overlay shift determination

The systems and methods enable the determination of the magnitude and direction of overlay of at least two elements in two layers. Overlay measurements along two axes can be obtained using four probe pads and without requiring a decoder. Overlay measurements along a single axis can be obtained using three probe pads and without requiring a decoder. The systems and methods according to this invention require less space and are more time efficient than conventional measurement structures. In the systems and methods of this invention, offsets in a direction are calculated from resistance measurements.

Growing community of inventors

Fishkill, NY, United States of America

Faisal Azam