Presentation + Paper
21 November 2023 Innovative applications: extending photomask registration tool for critical dimension measurement to achieve high efficiency
Author Affiliations +
Abstract
In the semiconductor industry, photomask quality depends on various aspects including critical dimension (CD), overlay to other layers, defects, etc. Conventionally, photomask metrology tasks are performed by separate tools. For example, KLA LMS IPRO is used for registration, while CD-SEM or optical microscope is used for CD measurements. However, current CD tools have time-consuming measurements and difficulties to providing spatial CD variation across the photomask. To address these challenges, LMS IPRO tool, originally designed for registration measurement, provides a portable and fast CD measurement solution. The feasibility of CD measurement on LMS IPRO comes from its image processing mechanism. Algorithms analyze the intensity of captured images to figure out the pattern edges. The calculated CD commonly has deviation to the actual CD due to the unknown edge intensity threshold. Thus, we fed LMS IPRO the actual CD to do calibration before using this function in production scenarios. The calibrated CD ranges from 0.5μm to 13μm, which covers the mature technology node product sizes at Quanyi Mask Optoelectronic Technology Co. Ltd (QYMask). Verification results proved that LMS IPRO meets QY Mask’s mature-node mask CD measurement specifications. Therefore, it could (a) be temporary substitution in case optical CD tool is down, (b) concurrently measure CD and registration, (c) provide fast pre-check of CD uniformity.
Conference Presentation
© (2023) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Yifei Yu, Leo Zeng, Kevin Wang, Xavier Chen, Christian Holl, Claire Lu, Phil Cha, Vic Chang, Robert Tsai, Jerry Wei, and Lynne Yuan "Innovative applications: extending photomask registration tool for critical dimension measurement to achieve high efficiency", Proc. SPIE 12751, Photomask Technology 2023, 127510S (21 November 2023); https://doi.org/10.1117/12.2687005
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Critical dimension metrology

Calibration

Photomasks

Data modeling

Opacity

Image registration

Cadmium

RELATED CONTENT

Bringing SEM-contour based OPC to production
Proceedings of SPIE (March 31 2014)
Photomask linewidth comparison by PTB and NIST
Proceedings of SPIE (November 02 2015)
Filtering noisy data for T-less model calibration
Proceedings of SPIE (December 27 2002)
Mask calibration dominated methodology for OPC matching
Proceedings of SPIE (November 14 2007)

Back to Top