Comparing positive and negative tone development process for printing the metal and contact layers of the 32- and 22-nm nodes

Abstract

A strong demand exists for techniques that extend application of ArF immersion lithography. Besides techniques such as litho-friendly design, dual exposure/patterning schemes, customized illumination, alternative processing schemes are also viable candidates. One of the most promising alternative flows uses image reversal by means of a negative tone development (NTD) step with a Fujifilm solvent-based developer. Traditionally, contact and trench printing uses a dark-field mask in combination with positive tone resist and positive tone development. With NTD, the same features are printed in positive resist using light-field masks, and consequently with better image contrast. We present an overview of NTD applications, comparing the NTD performance to that of the traditional development. Experimental work is performed at a 1.35 numerical aperture, targeting the contact/metal layers of the 32-and 22-nm nodes. For contact printing, we consider both single-and dual-exposure schemes for regular arrays and 2-D patterns. For trench printing, we study 1-D, line end, and 2-D patterns. We also assess the etch capability and critical dimension uniformity performance of the NTD process. We proves the added value of NTD. It enables us to achieve a broader pitch range and/or smaller litho targets, which makes NTD attractive for the most advanced lithography applications, including double patterning. C 2010 Society of Photo-Optical Instrumentation Engineers.

Neutron Reflectivity Characterization of the Photoacid Reaction-Diffusion Latent and Developed Images of Molecular Resists for Extreme Ultraviolet Lithography

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Challenges for patterning process models applied to large scale

“…55 New processes are emerging for double patterning including litho-etch-litho-etch and litho-freeze-litho-etch, sidewall image transfer, and negative tone develop. 56 Novel and chemical and thermal pattern shrink processes will continue to find their way into manufacturing. These processes represent a wide range of complex physicochemical processes, but the phenomenological compact model approach, based upon relatively few optical parameter inputs, and empirical CD/contour outputs, will no doubt be able to accurately represent these processes for full-chip simulation.…”

NXE:3100 full wafer imaging performance and budget verification

“…However, the relatively small amount of EUV photons defining the pattern, compared to ArFi, raises a concern for a high local CDU due to shot noise effects 6 . The local CDU was measured for 40nm dense CHs exposed on the NXE:3100 using conventional illumination and compared results from the NXT:1950i, using a double dipole exposure and negative tone develop 7 . Figure 17 shows the measured process windows for both the EUV and ArFi exposure.…”