A multi crossing wire bonding technique for high power transistor packages

This paper describes an advanced wire bonding technique which utilizes a three-dimensional multi crossing structure for high power RF transistor packages. High power transistor packages consist of high power transistor die, chip capacitors, metallic package housing, in/out lead connection, and lots of bonding wires. For a given transistor die and restricted narrow area inside the package housing, the output power strongly depends on the matching networks, i.e. chip capacitor value and the length of bonding wires which correspond to inductances for matching. In this study, a multi crossing wire bonding technique is proposed in order to provide the longer bonding wire than the conventional stepping stone wire bonding structure within the given restricted area inside the package housing. As an example, a 16 mm GaN high power transistor package is designed and compared using the both wire bonding techniques. The transistor package using the proposed multi crossing wire bonding technique shows improved linear power gain by 2 dB at 1 GHz for the same input power.