Silicon dioxide-polysilicon multi-layered stack etching with plasma etch chamber employing non-corrosive etchants

摘要: Multilayered stacks having layers of silicon interleaved with a dielectric, such as dioxide, are plasma etched non-corrosive process gas chemistries. Etching plasmas fluorine source gases, SF6 and/or NF3 typically only suitable for dielectric layers, energized by pulsed RF to achieve high aspect ratio etching silicon/silicon dioxide bi-layers without the addition corrosive HBr or Cl2. In embodiments, mask open etch and multi-layered stack performed in same processing chamber enabling single chamber, recipe solution patterning stacks. 3D NAND memory cells fabricated plug word line separation etches employing fluorine-based, pulsed-RF etch.