Method for preventing redeposition of etching products onto substrate surfaces during a tungsten re-etching process in the production of LSI circuits

摘要

A method for back-etching of tungsten-coated substrate surfaces in the production of large-scale integrated circuits includes pressing a substrate against a cooled specimen holder during back-etching with a retaining ring being disposed on an edge of the substrate and only locally retaining the edge of the substrate with the retaining ring at retaining locations distributed over the circumference of the retaining ring. The retaining locations are backup-free relative to etching products liberated in the back-etching, causing the etching products to flow past the retaining locations and be purposefully deposited outside the substrate surface.