Approaches to CMOS integration of epitaxial gadolinium oxide high-K dielectrics

Two process concepts for integration of novel gate stacks with epitaxial high-k dielectrics and metal gate electrodes are presented. A "gate first" process based on a planar gate stack on ultra thin SOI material has been used for successful fabrication of MOSFETs with TiN/Gd
₂
O
₃
gate stack. Furthermore MOSFETs with W/Gd
₂
O
₃
gate stack have been fabricated with a replacement gate process. This is the first successful attempt to integrate crystalline high-K dielectrics into a "gentle" damascene metal gate process in order to reduce process induced oxide damages