Patent ID: 11874605
Assignee: KLA CORPORATION
Field: Optics (Instruments)
Classification: CPC G  H | IPC G  H

Claim 0:
1. A metrology target design method comprising:
using optical critical dimension data related to at least one designed overlay metrology target as an estimation of a discrepancy between a target model and a corresponding actual target on a wafer, wherein the optical critical dimension data is at least partially derived from a measurement, with a critical dimension metrology sensor, of at least one verification target comprising one or more overlay target features, wherein the one or more overlay target features of the at least one verification target comprise at least one of: a pitch, a segmentation and a topography which is identical to a corresponding feature of at least one overlay metrology target as the at least one designed overlay metrology target; and
adjusting a metrology target design model to compensate for the discrepancy, wherein the adjusting is carried out with respect to at least one of a critical dimension, an optical material characteristic, a film thickness, topography or presence of process variation, wherein the process variation relates to at least one of an induced topography, a deposited topography, an etched topography, or chemical mechanical planarization dishing.