Fujitsu Limited and Fujitsu Laboratories Ltd. reported that they have developed a crystal structure that both increases current and voltage in gallium-nitride (GaN) high electron mobility transistors (HEMTs). According to the companies, this performance improvement effectively triples the output power of transistors for microwave band transmitters.
Fujitsu says that applying the new technology would increase the output power of the transistors in power amplifiers for weather radar. The company also asserts that this increase in performance could multiply the observation range of weather radar by 2.3 times, enabling earlier detection of cumulonimbus clouds that can develop into torrential rainstorms.
The company noted that with conventional technology, applying high voltage could easily damage the crystals that compose a transistor. However, Fujitsu has now developed a patent-pending crystal structure that dispersing the applied voltage to the transistor, thereby preventing crystal damage. The company reports that the new technology has enabled it to successfully achieve the world’s highest power density at 19.9 watts per millimeter of gate width for GaN HEMT employing indium-aluminum-gallium nitride (InAlGaN) barrier layer.
This research was partially funded by Innovative Science and Technology Initiative for Security, established by the Acquisition, Technology & Logistics Agency (ATLA) of the Japanese Ministry of Defense. Details about this technology will be presented at the International Symposium on Growth of III-Nitrides (ISGN-7), an international conference about nitride semiconductor crystal growth, in Warsaw, Poland, from August 5-10.