36 Journal of Power Electronics, Vol. 9, No. 1, January 2009 JPE 9-1-4 Review on Gallium Nitride HEMT Device Technology for High Frequency Converter Applications Nor Zaihar Yahaya † , Mumtaj Begam Kassim Raethar * and Mohammad Awan * †* Dept. of Electrical and Electronics Eng., Universiti Teknologi PETRONAS, Tronoh, Malaysia ABSTRACT This paper presents a review of an improved high power-high frequency III-V wide bandgap (WBG) semiconductor device, Gallium Nitride (GaN). The device offers better efficiency and thermal management with higher switching frequency. By having higher blocking voltage, GaN can be used for high voltage applications. In addition, the weight and size of passive components on the printed circuit board can be reduced substantially when operating at high frequency. With proper management of thermal and gate drive design, the GaN power converter is expected to generate higher power density with lower stress compared to its counterparts, Silicon (Si) devices. The main contribution of this work is to provide additional information to young researchers in exploring new approaches based on the device’s capability and characteristics in applications using the GaN power converter design. Keywords: Gallium nitride device, High frequency, Power converter 1. Introduction Gallium Nitride (GaN) high-electron mobility transistor (HEMT) is one of the wide bandgap (WBG) semiconductor group III-V devices, besides Silicon Carbide (SiC) and diamond. These devices are known to have large energy bandgap ranging from 2.3 eV to 5.6 eV while Silicon (Si) devices normally have smaller energy around 1.12 eV. This difference in energy bandgap makes group III-V devices superior in high speed operations and thermal handling capability. The emergence of the WBG devices results in substantial improvement of power electronic converter systems in terms of higher blocking voltages, efficiency and reliability. The first study of GaN devices was initiated in 1970s by Ponkove, Akasaki and many others [1] . Currently, GaN has been widely used in optoelectronics and microwave applications in the form of nitride-based light emitting diodes (LEDs) especially in mobile phones. The latest GaN device was tested for radio frequency (RF) operation at frequencies up to 110 GHz [2] . In transistor switch operation, GaN has been demonstrated with blocking voltages of 600 V [3] which is suitable for high voltage switching operation. The maximum current handling capability is 30 A when developed on SiC substrates [4] . GaN is preferred due to its ability to improve utility applications compared to other non III-V group devices such as silicon-based transistors such as power MOSFETs. With regards to power supply development, a high power MOSFET switch can operate at a maximum operating frequency of 500 kHz with current handling capability of Manuscript received March19, 2008; revised Oct. 23, 2008. † Corresponding Author: norzaihar_yahaya@petronas.com.my Tel: +60-5-368-7823, Fax: +60-5-365-7443, Univ. Teknologi PETRONAS * Dept. of Electrical and Electronics Eng., Univ. Teknologi PETRONAS, Malaysia