Enabling high resolution pillar patterning using EUV metal oxide resist by functional underlayer design

Ability to print pillar structures using metal oxide resist is critical for enabling next generation DRAM patterning. However, patterning pillar structures using traditional wet develop process are generally considered more challenging than line and space pattern as smaller footprint of pillars make them more susceptible to collapse during developing process. To address this issue, ultrathin functional underlayers for metal oxide resist were developed which can improve pillar collapse, reduce dose, and increase overall process window.