Electronic components shrink in their dimensions due to space restrictions on electronic printed circuit boards (PCB). This is only possible on a limited scale for integrated circuits. Their number of connectors increases due to the growing complexity of the semiconductors. However the miniaturisation of the connectors is limited because of handling constrains. To overcome this dilemma the connectors of the ICs have been moved from the sides to the bottom where a matrix of solder balls forms the connection to the PCB, so called Ball Grid Arrays (BGA). Due to legislative reasons the balls of these components are made of lead free solder. However, there are still applications where tin lead solder is mandatory. It was the goal of the investigation to work out the process parameters to solder lead free BGAs with tin lead solder and to evaluate the degradation of this mixed technology.