Pattern collapse and line width roughness reduction by surface conditioner solutions for 248-nm lithography

Abstract

In this paper, surface conditioners were applied during the post-develop process to extend the capability of 248nm lithography processing below the k1= 0.30 threshold. The interaction between surface conditioner and photoresist was found to be a critical parameter in affecting pattern collapse, line width roughness (LWR), and process latitude. Tailoring the surface interaction properties required balancing between surface conditioners that had weak interactions that improved pattern collapse only marginally, to surface conditions with strong interactions that produced a considerable reduction in LWR but provided no benefit to pattern collapse or process latitude when compared to DI water. The surface conditioners with optimized resist interactions provided significant improvement in all performance parameters including reduced pattern collapse, improved LWR, and enlarged usable process latitude.