Title
Improved sub-surface AFM using photothermal excitation
Author
van Reijzen, M.E.
Tamer, M.S.
van Es, M.H.
van Riel, M.C.J.M.
Keyvani Janbahan, A.
Sadeghian Marnani, S.
van der Lans, M.J.
Publication year
2019
Abstract
In this paper, we present an AFM based subsurface measurement technique that can be used for overlay and critical dimensions (CD) measurements through optically opaque layers. The proposed method uses the surface elasticity map to resolve the presence and geometry of subsurface structures. To improve the imaging performance of the AFM based subsurface measurements, we made use of photothermal excitation of the AFM cantilever together with a frequency modulation scheme. The experimental results show a significant improvement in the quality of the image, which leads to a more accurate and reliable CD and overlay measurement.
Subject
AFM
Subsurface imaging
Frequency modulation
Photothermal excitation
Critical dimensions and overlay metrology
High Tech Systems & Materials
Industrial Innovation
To reference this document use:
http://resolver.tudelft.nl/uuid:b3312949-6ae3-467a-952e-b209dce3360f
TNO identifier
873654
Publisher
TNO, Delft
Source
Proceedings Metrology, Inspection, and Process Control for Microlithography XXXII, 2018, San Jose, CA, USA
Document type
conference paper