Fujitsu Registers Success In Increasing Output Power of Gallium-Nitride Transistors by Three Times

Fujitsu Limited and Fujitsu Laboratories recently announced development of a crystal structure that can enhance both voltage and current in Gallium-Nitride (GaN) based high electron mobility transistors (HEMT). They have registered success in pulling up the output power value of transistors by three times in the microwave band. The GaN HEMT technology is capable of serving as power amplifiers for devices, like weather radar, through application of advanced technology in this region. It is estimated that it will expand the observation range of radar by 2.3 times allowing early detection of cumulonimbus clouds that often result into torrential rainstorms.

Fig. 1: The Crystal Damage Mechanism and the Latest Developed Technology

(Image Source: Fujitsu)

For expansion of observation range of equipments such as radars, it is highly essential to enhance the output power value of transistors especially the ones that are used in power amplifiers. With the help of conventional technology, application of high voltage can easily lead to damage of crystals that constitute a transistor. It is for this reason, it was not easy to enhance voltage and current values simultaneously that is needed for realizing high-output power GaN HEMTs.

Fujitsu and Fujitsu Laboratories have recently developed a crystal structure that brings improvement in voltage operation by distributing the applied voltage to transistor and thus keep the crystal damage at bay. This innovation has allowed Fujitsu to take credit for highest power density in the world at 19.9 watts per millimeter of gate width for GaN HEMT using indium-aluminium-gallium nitride barrier layer.

This research was supported by Innovative Science and technology Initiative for Security partially. Details of this new technology will be shared at the International Symposium of Growth of III-NItrides.