公开(公告)号：US20190259618A1

公开(公告)日：2019-08-22

申请号：US15898851

申请日：2018-02-19

Applicant: STMicroelectronics (Crolles 2) SAS

Inventor： Florian Domengie ,  Pushpendra Kumar

IPC: H01L21/28 ,  H01L29/66 ,  H01L29/78 ,  H01L29/49

Abstract: Local variability of the grain size of work function metal, as well as its crystal orientation, induces a variable work function and local variability of transistor threshold voltage. The metal nitride for the work function metal of the transistor gate is deposited using a radio frequency physical vapor deposition with process parameters selected so as to produce grains of material exhibiting a uniaxial grain orientation. The uniaxial grain structure for the metal nitride work function metal layer (such as with TiN) reduces local variability in threshold voltage.