Etch/metallization process sequence integration-impact of Al texture on Al etch performance

Very successful process sequence integration has been demonstrated with Al etch/CVD/PVD-Al deposition. For CVD-Al with poor Al(111) texture, Al sidewall attack occurs at the CVD-Al/TiN-barrier interface. However, with a thin Ti layer on top of the CVD-TiN film, excellent CVD-Al(111) texture is produced without Al sidewall attack. Furthermore, Cu residue performance of CVD/PVD-Al-1.0%Cu is observed to be quite similar to that on PVD-Al-0.5%Cu. The impact of oxide substrate material on Al etch performance is also addressed.