US 12,033,893 B2
Contact plug with impurity variation
Chung-Chiang Wu, Taichung (TW); Hsueh Wen Tsau, Zhunan Township (TW); Chia-Ching Lee, New Taipei (TW); Cheng-Lung Hung, Hsinchu (TW); and Ching-Hwanq Su, Tainan (TW)
Assigned to TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD., Hsinchu (TW)
Filed by Taiwan Semiconductor Manufacturing Co., Ltd., Hsinchu (TW)
Filed on Jul. 26, 2023, as Appl. No. 18/359,016.
Application 17/120,696 is a division of application No. 15/967,497, filed on Apr. 30, 2018, granted, now 10,867,848, issued on Dec. 15, 2020.
Application 18/359,016 is a continuation of application No. 17/869,462, filed on Jul. 20, 2022, granted, now 11,769,694.
Application 17/869,462 is a continuation of application No. 17/120,696, filed on Dec. 14, 2020, granted, now 11,404,312, issued on Aug. 2, 2022.
Prior Publication US 2024/0021471 A1, Jan. 18, 2024
Int. Cl. H01L 21/768 (2006.01); H01L 23/532 (2006.01); H01L 23/535 (2006.01); H01L 29/66 (2006.01); H01L 29/78 (2006.01)
CPC H01L 21/76871 (2013.01) [H01L 21/76805 (2013.01); H01L 21/7684 (2013.01); H01L 21/76843 (2013.01); H01L 21/76862 (2013.01); H01L 21/76889 (2013.01); H01L 21/76895 (2013.01); H01L 23/53266 (2013.01); H01L 23/535 (2013.01); H01L 29/66795 (2013.01); H01L 29/7851 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method of forming a semiconductor device, the method comprising:
forming a dielectric layer over a conductive feature;
forming recess in the dielectric layer; and
forming a contact plug in the recess of the dielectric layer, forming the contact plug comprising:
forming a conductive layer along sidewalls of the recess, a first portion of the conductive layer proximal a bottom of the recess comprising a first concentration of a first impurity, a second portion of the conductive layer proximal a top of the recess comprising a second concentration of the first impurity, and wherein the second concentration of the first impurity is less than the first concentration of the first impurity, wherein the first impurity comprises oxygen or boron; and
forming a conductive material over the conductive layer.