US 11,756,832 B2
Gate structures in semiconductor devices
Pei Ying Lai, Hsinchu (TW); Chia-Wei Hsu, Taipei (TW); Cheng-Hao Hou, Hsinchu (TW); Xiong-Fei Yu, Hsinchu (TW); and Chi On Chui, Hsinchu (TW)
Assigned to TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD., Hsinchu (TW)
Filed by Taiwan Semiconductor Manufacturing Company, Ltd., Hsinchu (TW)
Filed on Jan. 3, 2020, as Appl. No. 16/733,959.
Claims priority of provisional application 62/908,137, filed on Sep. 30, 2019.
Prior Publication US 2021/0098303 A1, Apr. 1, 2021
Int. Cl. H01L 21/8234 (2006.01); H01L 29/78 (2006.01); H01L 29/66 (2006.01); H01L 29/417 (2006.01)
CPC H01L 21/823431 (2013.01) [H01L 29/41791 (2013.01); H01L 29/6681 (2013.01); H01L 29/785 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method comprising:
depositing a high-k gate dielectric layer over and along sidewalls of a semiconductor fin;
depositing an n-type work function metal layer over the high-k gate dielectric layer, the n-type work function metal layer comprising aluminum and being deposited to have a same material composition throughout;
performing a passivation treatment to implant a passivating species into the high-k gate dielectric layer through the n-type work function metal layer, wherein the passivation treatment comprises a remote plasma process, wherein the passivation treatment is directly applied to an aluminum compound of the n-type work function metal layer, wherein the passivation treatment forms a passivated region comprising the passivating species in the high-k gate dielectric layer and the n-type work function metal layer, and wherein a ratio of a first average thickness of the passivated region on the sidewalls of the semiconductor fin to a second average thickness of the passivated region on a top surface of the semiconductor fin is in a range of 0.8:1 to 0.9:1; and
depositing a fill metal over the n-type work function metal layer to form a metal gate stack over the high-k gate dielectric layer, the metal gate stack comprising the n-type work function metal layer and the fill metal.