Influence of OPC features on the profile of 2D mask patterns

Andrew Khoh, Thomas D Milster, Byoung Il Choi, Ganesh S. Samudra, Yihong Wu

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Citation (Scopus)

Abstract

With increasing use of OPC, there is a need to understand image formation better. The widely used Hopkin's model gives believable results but yields little insight into image formation. We present in this paper a new image formation technique based on the Geometrical Theory of Diffraction (GTD). Using GTD, we obtained a relationship between the edge on the mask and the disturbance in image space. We call this disturbance the Diffraction Edge Response (DER). Heuristically, the strength of the DER must drop nearing the end of an edge. The DER is thus modulated by a certain function. At this point of the development, we could not derive an expression for this function. However, we postulate that the Modulation Function is the square root of the intensity of the edge segment. This postulate is justified by the excellent agreement with results obtained using existing simulation tool. Image formation is thus governed by the DER and the Modulation Function. If the new image formulation is separated into the cross and non-cross terms respectively, it is observed from simulations that the cross terms have values closed to zero at the feature boundary. This unique property, stemming from the nature of the DER, turns a non-linear problem into approximately a linear problem at the feature boundary. A host of problems could then be understood. Using this tool, we show how the behavior of a simple corner varies with NA, PC and its dimension. We also discuss the implications of this tool on current OPC strategy. We have assumed an aberration-free system and an infinitely-thin 2D mask in this development. It is possible to extend it to an aberrated system and to 3D-mask. That will be our work in the future.

Original languageEnglish (US)
Title of host publicationProceedings of SPIE - The International Society for Optical Engineering
EditorsA. Yen
Pages1127-1138
Number of pages12
Volume4691 II
DOIs
StatePublished - 2002
EventOptical Microlithography XV - Santa Clara, CA, United States
Duration: Mar 5 2002Mar 8 2002

Other

OtherOptical Microlithography XV
CountryUnited States
CitySanta Clara, CA
Period3/5/023/8/02

Fingerprint

Masks
masks
Diffraction
profiles
Image processing
geometrical theory of diffraction
diffraction
axioms
Modulation
disturbances
modulation
Aberrations
aberration
simulation
formulations

Keywords

  • 2D profile
  • Corner
  • GTD
  • Image formation technique
  • Line-end
  • OPC
  • Simulation

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Condensed Matter Physics

Cite this

Khoh, A., Milster, T. D., Choi, B. I., Samudra, G. S., & Wu, Y. (2002). Influence of OPC features on the profile of 2D mask patterns. In A. Yen (Ed.), Proceedings of SPIE - The International Society for Optical Engineering (Vol. 4691 II, pp. 1127-1138) https://doi.org/10.1117/12.474493

Influence of OPC features on the profile of 2D mask patterns. / Khoh, Andrew; Milster, Thomas D; Choi, Byoung Il; Samudra, Ganesh S.; Wu, Yihong.

Proceedings of SPIE - The International Society for Optical Engineering. ed. / A. Yen. Vol. 4691 II 2002. p. 1127-1138.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Khoh, A, Milster, TD, Choi, BI, Samudra, GS & Wu, Y 2002, Influence of OPC features on the profile of 2D mask patterns. in A Yen (ed.), Proceedings of SPIE - The International Society for Optical Engineering. vol. 4691 II, pp. 1127-1138, Optical Microlithography XV, Santa Clara, CA, United States, 3/5/02. https://doi.org/10.1117/12.474493
Khoh A, Milster TD, Choi BI, Samudra GS, Wu Y. Influence of OPC features on the profile of 2D mask patterns. In Yen A, editor, Proceedings of SPIE - The International Society for Optical Engineering. Vol. 4691 II. 2002. p. 1127-1138 https://doi.org/10.1117/12.474493
Khoh, Andrew ; Milster, Thomas D ; Choi, Byoung Il ; Samudra, Ganesh S. ; Wu, Yihong. / Influence of OPC features on the profile of 2D mask patterns. Proceedings of SPIE - The International Society for Optical Engineering. editor / A. Yen. Vol. 4691 II 2002. pp. 1127-1138
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