Abrasive-free planarization for EUV mask substrates

摘要

A process for abrasive-free chemical mechanical planarization of silicon thin film coated EUV mask substrates is disclosed. The process removes bumps and pits on the substrate thereby mitigating reflective errors in the mask. The process employs a two-step polishing procedure, in which the second step is abrasive-free and uses an amine or amine salt as the polishing agent.

主权项

1. A planarizing method comprising:
a) depositing a silicon material layer upon a substrate that includes a defect; and b) planarizing said silicon material layer, first with an abrasive planarizing fluid and then with an abrasive-free planarizing fluid to provide a silicon material layer from 10 to 100 nm thick over said substrate that includes a defect.