US 12,014,960 B2
Etch profile control of polysilicon structures of semiconductor devices
Kuo-Cheng Chiang, Hsinchu County (TW); Chih-Hao Wang, Hsinchu County (TW); and Kuan-Ting Pan, Taipei (TW)
Assigned to Taiwan Semiconductor Manufacturing Co., Ltd., Hsinchu (TW)
Filed by Taiwan Semiconductor Manufacturing Co., Ltd., Hsinchu (TW)
Filed on Apr. 19, 2021, as Appl. No. 17/234,138.
Application 17/234,138 is a continuation of application No. 16/877,345, filed on May 18, 2020, granted, now 10,985,072.
Application 16/877,345 is a continuation of application No. 16/246,209, filed on Jan. 11, 2019, granted, now 10,658,245, issued on May 19, 2020.
Application 16/246,209 is a continuation of application No. 15/800,959, filed on Nov. 1, 2017, granted, now 10,181,426, issued on Jan. 15, 2019.
Claims priority of provisional application 62/552,241, filed on Aug. 30, 2017.
Prior Publication US 2021/0257259 A1, Aug. 19, 2021
Int. Cl. H01L 21/8234 (2006.01); H01L 21/8238 (2006.01); H01L 27/088 (2006.01); H01L 27/092 (2006.01); H01L 29/08 (2006.01); H01L 29/423 (2006.01); H01L 29/51 (2006.01); H01L 29/66 (2006.01); H01L 29/78 (2006.01)
CPC H01L 21/823462 (2013.01) [H01L 21/823431 (2013.01); H01L 21/823821 (2013.01); H01L 27/0886 (2013.01); H01L 27/0924 (2013.01); H01L 29/0847 (2013.01); H01L 29/42368 (2013.01); H01L 29/66545 (2013.01); H01L 29/7856 (2013.01); H01L 29/517 (2013.01)] 20 Claims
OG exemplary drawing
 
9. A semiconductor device, comprising:
a fin structure; and
an oxide layer on the fin structure, comprising:
a first portion of the oxide layer on a top surface of the fin structure and comprising a first thickness; and
a second portion of the oxide layer on a sidewall of the fin structure and comprising a second thickness less than the first thickness, wherein the second thickness is substantially constant along the sidewall of the fin structure.