Consistent growth and successive development of GaN-HEMT for wireless communication

The world´s first commercialized GaN-HEMTs for power amplifiers in wireless basestation transmitter systems were successfully launched. The device characteristics of GaN-HEMT on SiC are superior to those of Si LDMOS-FET owing to the material properties. However, the mass-production of GaN-HEMT was significantly difficult for every semiconductor vender in the past. We developed an appropriate screening procedure and improve the quality of SiC substrate. Those measures enabled high volume production of GaN-HEMTs. In order to maximize the high efficiency characteristics, an inverse class-F design was applied to the output matching network inside a package. Various application engineering solutions, such as Doherty amplifier designs and DPD adaptation examples, were provided quickly for user friendliness and convenience. GaN-HEMTs have achieved considerable market position through successfully performed development and improvement.