A low-distortion K-band GaAs power FET

• Published in: IEEE transactions on microwave theory and techniques Vol. 36; no. 6; pp. 1023 - 1032
• Main Authors: Tan, T.S., Kotzebue, K., Braun, D.M., Centanni, J., McQuate, D.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.06.1988; Institute of Electrical and Electronics Engineers
• Subjects: Applied sciences; Circuit properties; Doping profiles; Electric, optical and optoelectronic circuits; Electronics; Exact sciences and technology; FETs; Gain; Gallium arsenide; K-band; Linearity; MESFETs; Microwave circuits, microwave integrated circuits, microwave transmission lines, submillimeter wave circuits; Power amplifiers; Power generation; Transconductance; Performance evaluation; Gallium Arsenides; Field effect transistor; Circuit design; K band; Microwave amplifier; Signal distortion; Power transistor
• ISSN: 0018-9480; 1557-9670
• DOI: 10.1109/22.3628

A K-band low-distortion GaAs power MESFET was developed by incorporating a pulse-type channel doping profile using molecular-beam-epitaxial technology and a novel 0.3- mu m T-shaped gate. The low-distortion FETs offer about 10 to 15 dBc improvement in second-harmonic distortion compared to devices fabricated on a uniformity doped active layer. Significantly larger power load-pull contours are obtained with the low-distortion devices, indicating the improved linearity of these devices. In an 8-20-GHz single-stage broad-band amplifier, up to 10 dBc improvement in harmonic performance was achieved using the low-distortion device. This low-distortion device exhibits very linear transconductance as a function of the gate bias. A typical 750- mu m-gate-width device is capable of 26 dBm of output power with 6 dB of gain, and power-added efficiency in excess of 35% when measured at 18 GHz. At 25 GHz, the device is capable of 24 dBm of output power with 5 dB associated gain.< >