A self-aligned double patterning technology using TiN as the sidewall spacer

The TiN was conventionally used as barrier layers for both tungsten plug and AlCu metal lines. This paper reveals a novel back end of line (BEOL) self-aligned double patterning (SADP) technology, which applied TiN as a spacer material. The relative processes are introduced and discussed in detail. The new SADP approach was further applied for Cu damascene structure constructions in the advanced non-volatile memory (NVM).