	US 11,791,309 B2
	Process for electrically connecting contact surfaces of electronic components
Yean Mee Pun, Singapore (SG); Murali Sarangapani, Singapore (SG); Xi Zhang, Singapore (SG); Il Tae Kang, Incheon (KR); Abito Danila Bayaras, Singapore (SG); Kim Hui Chong, Singapore (SG); Sylvia Sutiono, Singapore (SG); Chee Wei Tok, Singapore (SG); and Tae Yeop James Kim, Gyeonggi-Do (SG)
Assigned to HERAEUS MATERIALS SINGAPORE PTE. LTD., Singapore (SG)
Appl. No. 17/309,506
Filed by Heraeus Materials Singapore Pte. Ltd., Singapore (SG)
PCT Filed Dec. 12, 2018, PCT No. PCT/SG2018/050609 § 371(c)(1), (2) Date Jun. 2, 2021, PCT Pub. No. WO2020/122809, PCT Pub. Date Jun. 18, 2020.
Prior Publication US 2022/0037284 A1, Feb. 3, 2022
Int. Cl. B23K 20/00 (2006.01); H01L 23/00 (2006.01)

CPC H01L 24/85 (2013.01) [B23K 20/005 (2013.01); H01L 24/45 (2013.01); H01L 2224/45015 (2013.01); H01L 2224/45139 (2013.01); H01L 2224/45572 (2013.01); H01L 2224/45644 (2013.01); H01L 2224/45655 (2013.01); H01L 2224/45664 (2013.01); H01L 2224/85181 (2013.01); H01L 2224/85205 (2013.01)]

19 Claims

1. A process for electrically connecting a contact surface of a first electronic component with a contact surface of a second electronic component comprising the subsequent steps:

(1) capillary wedge bonding a wire having a circular cross-section with an average diameter in the range of 8 to 80 μm to the contact surface of the first electronic component,

(2) forming a wire loop between the capillary wedge bond formed in step (1) and the contact surface of the second electronic component, and

(3) stitch bonding the wire to the contact surface of the second electronic component,

wherein the capillary wedge bonding of step (1) is carried out with a ceramic capillary having a face angle within the range of from zero to 4 degrees,

wherein the wire comprises a wire core with a surface, the wire core having a double-layered coating superimposed on its surface,

wherein the wire core consists of a material selected from the group consisting of pure silver, doped silver with a silver content of >99.5 wt. % and silver alloys with a silver content of at least 89 wt. %, and

wherein the double-layered coating comprises a 1 to 50 nm thick inner layer of nickel or palladium and an adjacent 5 to 200 nm thick outer layer of gold.