An embodiment is a method including forming a first package and a second package. The chassis underframe is mounted on the body via elastic bearings and has an annular mounting on which the spring plate of the spring is supported before the wheel suspension system is installed. When a predetermined time prior to the close of operations E and D is reached, the supply of etching or protective-film deposition gas is halted, and the exhaust flow rate of gas exhausted from the chamber is made greater than that previously. In other embodiments, the system may also have more than two detectors arrays andor more than one source array.