Challenges in excimer laser lithography for 256M DRAM and beyond

Abstract

New chemically amplified positive resist and offaxis illumination technique of K r F excimer laser lithography has been developed and successfully applied to the fabrication of 0.25pm-rule 256M

Design, Synthesis, and Evaluation of a Novel Amphiphilic Alicyclic Polymer Having γ-Hydroxy Acid Structure

“…Methacrylate polymers containing alicyclic hydrocarbons − and copolymers of norbornene derivatives − have been proposed as the base polymer for ArF single-layer resists due to their high transparency and good dry-etching resistance. We have developed alicyclic polymers having half-acid ester structure that exhibit moderate transparency, good dry-etching resistance, and good alkali solubility (Scheme ) .…”

New Protective Groups in Alicyclic Methacrylate Polymers for 193-nm Resists.

“…In spite of the limitation in the matrix polymers for such short-wavelength light, transparent and etch-resistant materials have been reported in a few brief years by workers at Fujitsu [5][6][7][8][9], Matsushita [10], IBM/MIT team [1 1 ], NEC [12], and Toshiba [13]. Much efforts have been focused on methacrylate polymers with alicyclic pendant groups to demonstrate sub-0.2-µm resolution to date.…”

Further developments in surface imaging resists.

“…There have also been several recent developments in transparent, single layer methacrylate based resists. [7][8][9] More work needs to be done on these systems to improve their generally low etch resistance and overcome thin film interference effects. In the surface imaging process, Figure 1, the photoresist is exposed to form a latent image in only a thin top section of the resist film.…”