Aerial image degradation effects due to imperfect sidewall profiles of EAPSM mask for 130-nm device node: 3D EMF simulations and wafer printing results

Won D. Kim; Benjamen M. Rathsack

doi:10.1117/12.474576

30 July 2002 Aerial image degradation effects due to imperfect sidewall profiles of EAPSM mask for 130-nm device node: 3D EMF simulations and wafer printing results

Won D. Kim, Benjamen M. Rathsack

Author Affiliations +

Proceedings Volume 4691, Optical Microlithography XV; (2002) https://doi.org/10.1117/12.474576
Event: SPIE's 27th Annual International Symposium on Microlithography, 2002, Santa Clara, California, United States

Abstract

As our chip producing industry gearing up for mass production of 130nm device technology node, use of EAPSM (Embedded Attenuated Phase Shift Mask) technology in the critical pattern levels became unavoidable because of the low k₁ factor lithography involved. However, this 2-layer EAPSM material (attenuator material covered with Chrome) requires two distinctively separate lithography/etch processes needed to be carried out. These added complexities of processes are prone to degradation of the absorber material's (MoSi) sidewall leading to imperfect sidewall profiles (top corner rounding, off-normal sidewall angle, etching intrusion into quartz substrate, footing, . . . etc.). These imperfections of sidewall cause aerial image degradations thus reduce effectiveness of full benefits of PSM technology. In this paper, we discuss our findings of mask level aerial image degradation dependency on EAPSM material sidewall imperfections, which result from immature mask making processes, and assessments of its effects on pattern transfer onto wafer level using 3&2D EMF and subsequent lithography simulations. The results were then, compared to actual wafer results for the wafer level printing confirmation to the simulation results. We distinguish consequence of resulting aerial image differences between EMF simulations vs. Kirchhoff approximation (treatment of absorber to be infinitely thin layer; normally used in conventional lithography simulations) in the KrF EAPSM material (MoSi). Furthermore, we have carried out look-ahead assessments for ArF (193nm) lithography using ArF EAPSM material (MoSiON) and made association between the sidewall profile variations and CD uniformity performance of EAPSM. We will make case that 3D EMF capability consideration is important in the low k₁ factor lithography simulations.

Citation Download Citation

Won D. Kim and Benjamen M. Rathsack "Aerial image degradation effects due to imperfect sidewall profiles of EAPSM mask for 130-nm device node: 3D EMF simulations and wafer printing results", Proc. SPIE 4691, Optical Microlithography XV, (30 July 2002); https://doi.org/10.1117/12.474576

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available