Defect Free HDIS Process for Sub 28nm HKMG Using Reducing Chemistry

High dose implant strip (HDIS,) has been one of the focuses for yield enhancement. It is a moving target since implantation dose, energy and layer number are continuously optimized for better device performance. The pure reducing processes developed are optimized for gate first high κ metal gate (HKMG) integration scheme to accommodate low gate oxidation requirement. Higher hydrogen containing content and other parameters were tested and showed good trend on residue removal yet reaching a limit. Mechanism study has led to a new reactor design. The processes developed showed zero defect post dry and reduction trend of SiGe substrate loss in short loop tests. The throughput can be more than doubled compare to a baseline FG process.