US 12,230,595 B2
Metal bumps and method forming same
Ming-Da Cheng, Taoyuan (TW); Yung-Ching Chao, Gukeng Township (TW); Chun Kai Tzeng, Hsinchu (TW); Cheng Jen Lin, Kaohsiung (TW); Chin Wei Kang, Tainan (TW); Yu-Feng Chen, Hsinchu (TW); and Mirng-Ji Lii, Sinpu Township (TW)
Assigned to TAIWAN SEMICONDUCTOR MANUFACTURING CO., LTD., Hsinchu (TW)
Filed by Taiwan Semiconductor Manufacturing Co., Ltd., Hsinchu (TW)
Filed on May 28, 2021, as Appl. No. 17/333,187.
Application 17/333,187 is a division of application No. 16/458,719, filed on Jul. 1, 2019, granted, now 11,024,593.
Claims priority of provisional application 62/738,511, filed on Sep. 28, 2018.
Prior Publication US 2021/0288009 A1, Sep. 16, 2021
Int. Cl. H01L 23/00 (2006.01); H01L 23/31 (2006.01); H01L 23/522 (2006.01); H01L 23/488 (2006.01)
CPC H01L 24/11 (2013.01) [H01L 23/3192 (2013.01); H01L 23/5226 (2013.01); H01L 24/08 (2013.01); H01L 24/12 (2013.01); H01L 24/13 (2013.01); H01L 24/16 (2013.01); H01L 24/32 (2013.01); H01L 23/488 (2013.01); H01L 24/03 (2013.01); H01L 24/05 (2013.01); H01L 2224/0401 (2013.01); H01L 2224/32501 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A structure comprising:
a metal pad comprising a first top surface;
a passivation layer contacting the metal pad, wherein the passivation layer comprises a second top surface comprising:
a first portion located beyond an edge of the metal pad;
a second portion overlapping the metal pad; and
a sidewall joining the second portion of the second top surface to the first top surface, wherein the sidewall forms a corner with the first top surface;
a polymer layer comprising a third top surface, wherein the polymer layer is over and contacting the metal pad, and wherein the polymer layer comprises:
rising-up portions comprising third portions of the third top surface of the polymer layer; and
additional portions farther away from the metal pad than the rising-up portions, wherein the additional portions comprise fourth portions of the third top surface of the polymer layer, wherein the third portions are higher than the fourth portions, and wherein the third portions are more curved than respective underlying parts of the second portion of the second top surface of the passivation layer; and
a metal bump comprising:
a via portion in the polymer layer, wherein the via portion comprises:
a straight sidewall;
a straight bottom surface; and
a round bottom corner comprising a top end connecting to the straight sidewall, and a bottom end connecting to the straight bottom surface, wherein the corner is sharper than the round bottom corner, and wherein the rising-up portions located on opposite sides of the via portion have a same shape and a same rising-up height.