US 12,302,599 B2
Semiconductor device and formation method thereof
Wei-Chiang Hung, Changhua (TW)
Assigned to TAIWAN SEMICONDUCTOR MANUFACTURING CO., LTD., Hsinchu (TW)
Filed by TAIWAN SEMICONDUCTOR MANUFACTURING CO., LTD., Hsinchu (TW)
Filed on Jun. 21, 2022, as Appl. No. 17/845,036.
Application 17/845,036 is a division of application No. 16/884,908, filed on May 27, 2020, granted, now 11,393,910.
Claims priority of provisional application 62/963,733, filed on Jan. 21, 2020.
Prior Publication US 2022/0328638 A1, Oct. 13, 2022
Int. Cl. H01L 29/417 (2006.01); H01L 21/285 (2006.01); H01L 21/768 (2006.01); H01L 23/535 (2006.01); H01L 29/08 (2006.01); H01L 29/45 (2006.01); H01L 29/66 (2006.01); H01L 29/78 (2006.01); H10D 30/01 (2025.01); H10D 30/62 (2025.01); H10D 62/13 (2025.01); H10D 64/62 (2025.01)
CPC H10D 30/6219 (2025.01) [H01L 21/28518 (2013.01); H01L 21/76805 (2013.01); H01L 21/76862 (2013.01); H01L 21/76877 (2013.01); H01L 21/76895 (2013.01); H01L 23/535 (2013.01); H10D 30/024 (2025.01); H10D 30/6211 (2025.01); H10D 62/151 (2025.01); H10D 64/62 (2025.01)] 20 Claims
OG exemplary drawing
 
1. A semiconductor device, comprising:
a fin structure extending above a substrate;
a source/drain region in the fin structure;
a first inter-layer dielectric (ILD) layer over the source/drain region;
a first contact plug extending through the first ILD layer to a silicide region of the source/drain region, wherein the first contact plug comprises:
a metallic fill layer; and
a conductive barrier layer conformally surrounding a bottom portion of the metallic fill layer, wherein the conductive barrier layer has a material different from a material of the metallic fill layer, and a topmost surface of the conductive barrier layer is lower than a topmost surface of a non-linear top surface of the metallic fill layer;
a second contact plug over the first contact plug, wherein the metallic fill layer of the first contact plug has a protruding portion extending above the first ILD layer and laterally surrounding a lower part of the second contact plug; and
a second ILD layer over the first ILD layer, wherein the protruding portion of the metallic fill layer of the first contact plug is in contact with a sidewall of the second ILD layer, wherein the second contact plug has a bottom surface lower than a bottom surface of the second ILD layer, an outer sidewall of the first contact plug is aligned with an outer sidewall of the second contact plug.