Chemically Amplified Negative Resists Based on Alicyclic Acrylate Polymers for 193-nm Lithography

Abstract

We have evaluated the effects of polymer structure on chemically amplified negative resists in terms of alkaline solubility, adhesion, and lithographic performance. Poly(hydroxytricyclo [5.2.1.0^{2, 6}]decyl acrylate (TCDAOH)₆₇-carboxytetracyclo[4.4.0.1^{2, 5}1^{7, 10}]dodecyl acrylate (CTCDDA)₃₃) exhibits sufficient alkaline solubility (dissolution rate (DR): 0.56μm/s in 2.38wt% TMAH solution) for use as a negative resist polymer, and a resist based on this polymer provides 0.17 μm line-and-space (L/S) resolution. By way of contrast, poly(TCDAOH₆₀- CTCDDA₄₀) (D.R.: 0.95μm/s) dose not provide good resolution because the developer permeates into the pattern. To improve adhesion, we have developed three new acrylate monomers: 3, 4-epoxytricyclo[5.2.1.0^{2, 6}]decyloxyethyl acrylate (ETCDEA), 5-acryloyloxy-6-hydroxynorbornane-2-carboxylic 6-lactone (AHNCL), and 3, 4-dihydoroxy tricyclo[5.2.1.0^{2, 6}]decyloxyethyl (meth)acrylate (DTCDE(M)A). A resist based on poly(TCDAOH₆₄-CTCDDA₃₁-DTCDEA₅) provided a 0.15-μm- resolution isolated line pattern, and a resist based on poly(ETCDEA₄₂-CTCDDA₃₂- AHNCL₂₆) provided a 0.13-μm-resolution isolated line pattern. Both patterns were free of pattern stripping.