US 11,864,317 B2
Sn—Bi and copper powder conductive paste in through hole of insulating substrate
Masaaki Katsumata, Anan (JP); Koji Taguchi, Anan (JP); Norifumi Sasaoka, Tokushima (JP); and Yosuke Noda, Tokushima (JP)
Assigned to NICHIA CORPORATION, Anan (JP)
Filed by NICHIA CORPORATION, Anan (JP)
Filed on Dec. 1, 2020, as Appl. No. 17/107,953.
Application 17/107,953 is a division of application No. 16/583,160, filed on Sep. 25, 2019, granted, now 10,887,988.
Claims priority of application No. 2018-180393 (JP), filed on Sep. 26, 2018.
Prior Publication US 2021/0084763 A1, Mar. 18, 2021
Int. Cl. H01L 23/48 (2006.01); H01L 23/498 (2006.01); H01L 33/62 (2010.01); H05K 1/09 (2006.01); H05K 3/00 (2006.01); H05K 3/40 (2006.01); H05K 1/11 (2006.01); H01L 21/48 (2006.01)
CPC H05K 1/115 (2013.01) [H01L 21/486 (2013.01); H01L 21/4846 (2013.01); H01L 23/481 (2013.01); H01L 23/49822 (2013.01); H01L 33/62 (2013.01); H05K 1/095 (2013.01); H05K 3/0094 (2013.01); H05K 3/4038 (2013.01); H05K 3/4069 (2013.01); H01L 2933/0066 (2013.01); H05K 1/112 (2013.01); H05K 2201/09454 (2013.01); H05K 2201/09572 (2013.01); H05K 2201/09854 (2013.01); H05K 2201/10106 (2013.01); H05K 2203/0126 (2013.01); H05K 2203/0139 (2013.01); H05K 2203/0278 (2013.01); H05K 2203/1105 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A method of manufacturing a circuit substrate, the method comprising:
forming, in an insulating substrate and circuit patterns that are provided on a first surface and a second surface of the insulating substrate, a through-hole penetrating the insulating substrate and the circuit patterns such that the through-hole extends from a first hole opening to a second hole opening, the circuit patterns contain Cu as a main component;
filling, in the through-hole, an electrically conductive paste that is a melting-point shift electrically conductive paste including Sn—Bi solder powder, Cu powder, and resin, and forming a protrusion obtained by causing the electrically conductive paste to protrude from the through-hole;
performing pressure treatment on the protrusion near the through-hole; and
performing heat treatment on the insulating substrate whose protrusion is subjected to the pressure treatment and causing the circuit patterns and the electrically conductive paste to be electrically connected with each other,
in the performing pressure treatment, a diameter of the through-hole at a center in a thickness direction of the insulating substrate is larger than diameters of the first hole opening and the second hole opening.