Share Email Print

Proceedings Paper

Subwavelength alignment mark signal analysis of advanced memory products
Author(s): Xiaoming Yin; Alfred K. K. Wong; Donald C. Wheeler; Gary Williams; Eric A. Lehner; Franz X. Zach; Byeong Y. Kim; Yuzo Fukuzaki; Zhijian G. Lu; Santo Credendino; Timothy J. Wiltshire
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

The impact of alignment mark structure, mark geometry, and stepper alignment optical system on mark signal contrast was investigated using computer simulation. Several sub-wavelength poly silicon recessed film stack alignment targets of advanced memory products were studied. Stimulated alignment mark signals for both dark-field and bright-field systems using the rigorous electromagnetic simulation program TEMPEST showed excellent agreement with experimental data. For a dark-field alignment system, the critical parameters affecting signal contrast were found to be mark size and mark recess depth below silicon surface. On the other hand, film stack thickness and mark recess depth below/above silicon surface are the important parameters for a bright-field alignment system. From observed simulation results optimal process parameters are determined. Based on the simulation results some signal enhancement techniques will be discussed.

Paper Details

Date Published: 2 June 2000
PDF: 11 pages
Proc. SPIE 3998, Metrology, Inspection, and Process Control for Microlithography XIV, (2 June 2000); doi: 10.1117/12.386501
Show Author Affiliations
Xiaoming Yin, IBM Microelectronics Div. (United States)
Alfred K. K. Wong, IBM Microelectronics Div. (Hong Kong)
Donald C. Wheeler, IBM Microelectronics Div. (United States)
Gary Williams, IBM Microelectronics Div. (United States)
Eric A. Lehner, IBM Microelectronics Div. (United States)
Franz X. Zach, IBM Microelectronics Div. (United States)
Byeong Y. Kim, IBM Microelectronics Div. (United States)
Yuzo Fukuzaki, IBM Microelectronics Div. (United States)
Zhijian G. Lu, IBM Microelectronics Div. (United States)
Santo Credendino, IBM Microelectronics Div. (United States)
Timothy J. Wiltshire, IBM Microelectronics Div. (United States)

Published in SPIE Proceedings Vol. 3998:
Metrology, Inspection, and Process Control for Microlithography XIV
Neal T. Sullivan, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?