Physics and Technology of High-k Gate Dielectrics ii vol:2003 issue:22 pages:165-174
2nd International Symposium on High Dielectrics Constant Materials location:Orlando, Florida, USA date:12-16 October 2003
From an integration point of view, selective removal of high-k layers, whether this is done dry or wet, holds big challenges with respect to silicon recess. We developed a procedure to selectively remove high-k material from source/drain areas in devices without significant recess (less than or equal to 1nm). The approach involves a treatment of annealed CVD Hf-based films, followed by a selective wet removal. The treatment is actually a high-k layer damage by either ion bombardment from a plasma or ion implantation at low energies. After damaging, the high-k layer is removed selective towards most other layers exposed during processing. The developed chemistry is an HF-based wet chemical solution.