1 April 2005 Alignment mark signal simulation system for the optimum mark feature selection
Takashi Sato, Ayako Endo, Tatsuhiko Higashiki, Kazutaka Ishigo, Takuya Kono, Takashi Sakamoto, Yoshiyuki Shioyama, Satoshi Tanaka
Author Affiliations +
Abstract
Recently, requirements concerning overlay accuracy have become much more restrictive. For the accurate overlay, signal intensity and wave form from the topographical alignment mark have been examined by signal simulation. However, even if the results were in good agreement with actual signal profiles, it would be difficult to select particular alignment marks at each mask level by the signal simulation. Therefore, many mark candidates are left in the kerf area after mass production. To facilitate the selection, we propose a mark TCAD system. It is a useful system for the mark selection with the signal simulation performed in advance. In our system, the alignment mark signal can be easily simulated after input of some process material parameters and process of record (POR). The POR is read into the system and a process simulator makes stacked films on a wafer. Topographical marks are simulated from the stacked films and the resist pattern. The topographical marks are illuminated and reflected beams are produced. Imaging of the reflected beams through inspection optics is simulated. In addition, we show two applications. This system is not only for predicting and showing a signal wave form, but is also helpful for finding the optimum marks.
©(2005) Society of Photo-Optical Instrumentation Engineers (SPIE)
Takashi Sato, Ayako Endo, Tatsuhiko Higashiki, Kazutaka Ishigo, Takuya Kono, Takashi Sakamoto, Yoshiyuki Shioyama, and Satoshi Tanaka "Alignment mark signal simulation system for the optimum mark feature selection," Journal of Micro/Nanolithography, MEMS, and MOEMS 4(2), 023002 (1 April 2005). https://doi.org/10.1117/1.1898603
Published: 1 April 2005
Lens.org Logo
CITATIONS
Cited by 4 scholarly publications.
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Signal processing

Semiconducting wafers

Optical alignment

TCAD

Photomasks

Computer aided design

Metals

RELATED CONTENT


Back to Top