Method of installing integrated circuit package, its method and formed assembly thereof

The method installs BGA electronic components onto print circuit board through its mountable surfaces. The method uses first and second arrays of soldering balls (3ú¼6) with different characteristics. In process period of reflow soldering, interval between soldering balls (3) in first array and each soldering illuvium on print circuit board is controlled based on different characteristics of soldering balls. Thus, soldering balls (3) and each soldering illuvium are melted fully before they are contacted. Delayed fusion of soldering balls (6) is in use for keep interval between soldering balls (3) in first array and each soldering illuvium in order to moisten melted surfaces and guarantee their holding together to form high integrated electrical and mechanical contacts without interspace and/or breaking.