A Novel Main Chain Scission Type Photoresists for EUV Lithography

Abstract

In this work, we report the lithography performance of main chain scission type resists exposed with the ASML NXE3300B and 3400 EUV scanner. We also detail the advancements achieved in recent developments of the novel process conditions and the polymer properties of main chain scission type resist.

ZER02#1 series Zeon developed previously were better lithography performance than that of ZEP series. But ZER02#1 series were not able to achieve target values of lithography performance and need to use specific fluorine organic solvent. So, Zeon has developed a novel ZER02#3 resist by changing monomers and polymer properties in order to keep the EUV absorption at the same level of ZER02#1 and use common organic solvents as developer.

The lithographic performance of dense Line-Space (L/S) pattern and of orthogonal contact holes (C/H) pattern with ZER02#3 resist is presented. for L/S pattern, a resolution of 16 nm half pitch was achieved at the exposure dose of 54.5 mJ/cm(2), giving a biased LWR of 4.2 nm and a biased LER of 2.9 nm by NXE3300B. For orthogonal C/H pattern, 44nm pitch was resolved at 43.4mJ/cm(2) with a LCDU of 3.36nm by NXE3300B, 40 nm pitch was resolved at 77.5 mJ/cm(2), with a LCDU of 2.75 nm by NXE3400. ZER02#3 could enhance sensitivity and less defectivity as keeping lithography performance with ZER02#1. In addition to the enhancement of the lithographic performance achieved, fundamental studies such as Gel Permeation Chromatography were realized to better understand the pattering mechanism under EUV exposure.