4-GHz 15-W power GaAs MESFET

High-field behavior of GaAs MESFET's such as drain-source breakdown characteristics and visible light emission and a model explaining these phenomena are described. An FET structure with a high drain-source breakdown voltage in excess of 26 V has been developed following an analysis of the high-field behavior of the device. Typical characteristics of the fabricated devices at 4 GHz are as follows: P
out
= 9.6 W G
a
= 5 dB η
add
= 33.6 percent at 18 V from single chip (W
G
= 13 mm) P
out
= 15 W G
a
= 5 dB η
add
= 28.3 percent at 22 V from two chip (W
G
= 26 mm) where P
out
, G
a
, η
add
, and W
G
indicate the output power, associated power gain, power added efficiency, and total gate width of the FET's, respectively.