A method includes placing a package component over a carrier, encapsulating the package component in an encapsulant, and forming a connection structure over and electrically coupling to the package component. The formation of the connection structure includes forming a first via group over and electrically coupling to the package component, forming a first conductive trace over and contacting the first via group, forming a second via group overlying and contacting the first conductive trace, wherein each of the first via group and the second via group comprises a plurality of vias, forming a second conductive trace over and contacting the second via group, forming a top via overlying and contacting the second conductive trace, and forming an Under-Bump-Metallurgy (UBM) over and contacting the top via.