Patent ID: 9283641
Filing Date: 2016-03-15
CPC Classification: B23K,H01L

Claim Text:
1. A method comprising: depositing a flux material on one or more pads of a package substrate, the flux material including a rosin material and a thixotropic agent; and depositing one or more solder balls on the flux material disposed on the one or more pads, wherein depositing the one or more solder balls on the flux material is performed at a temperature greater than 80° C.; wherein the rosin material and the thixotropic agent are configured to resist softening at the temperature greater than 80° C.; wherein the rosin material includes one or more of rosin ester, hydrogenated rosin resin, dimerized resin, or modified resin; wherein the thixotropic agent includes one or more of an organic bentonite, amide wax, or hydrolyzed castor oil; wherein the rosin material represents 10% to 80% by weight of the flux material without a metal powder; and wherein the thixotropic agent represents 10% to 80% by weight of the flux material without the metal powder.