Slater Matsil, LLP
Methods for doping high-k metal gates for tuning threshold voltages
A method includes forming a first gate dielectric and a second gate dielectric over a first semiconductor region and a second semiconductor region, respectively, depositing a lanthanum-containing layer including a first portion and a second portion overlapping the first gate dielectric and the second gate dielectric, respectively, and depositing a hard mask including a first portion and a second portion overlapping the first portion and the second portion of the lanthanum-containing layer, respectively. The hard mask is free from both of titanium and tantalum. The method further includes forming a patterned etching mask to cover the first portion of the hard mask, with the second portion of the hard mask being exposed, removing the second portion of the hard mask and the second portion of the lanthanum-containing layer, and performing an anneal to drive lanthanum in the first portion of the lanthanum-containing layer into the first gate dielectric.
Taiwan Semiconductor Manufacturing Company, Ltd.
H H H H H H H H H H H H H H
H01L H01L H01L H01L H01L H01L H01L H01L H01L H01L H01L H01L H01L H01L
inventional inventional additional inventional inventional inventional inventional inventional inventional inventional inventional inventional additional inventional
Chih-Yu Chun Hsiung Hoong Shing Kuo-Feng Jian-Hao
Hsu Tsai Wong Yu Chen