Baseline overlay control with residual noise reduction

US10642161B1 · kind B1 · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Daniel A. Corliss · Cohoes, US
• Scott D. Halle · Slingerlands, US
• Richard C. Johnson · Selkirk, US
• Christopher F. Robinson · Hyde Park, US
• Chumeng Zheng · San Jose, US

Key dates

• Filing date: Oct 10, 2018
• Grant date: May 5, 2020
• Expiry date: Oct 10, 2038

Classification

• Technology area (CPC G): Physics
• CPC primary: G03F7/70633
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

Systems, methods and computer program products generally include a vector by vector subtraction method per wafer. A first layer is exposed to form a pattern image on a wafer and the overlay data of alignment registration marks at multiple locations relative to alignment registration marks of a baseline reference are measured. The first layer is then reworked and exposed to form the same pattern image and the overlay data of alignment registration marks at multiple locations relative to alignment registration marks of a first layer are measured. The overlay data of the reworked first layer is subtracted from the overlay data of the first layer to provide an overlay difference at each of the multiple locations. The overlay difference is converted to a pre-correction factor of a magnitude opposite that of the overlay difference and is applied to exposure of a second layer provided on the first layer.