No abstract

High-performance 0.1-µm InAlN/GaN high electron-mobility transistors (HEMTs) have been successfully developed for power amplifiers operating at E-band (targeting 71-76 and 81-86-GHz bands). High maximum drain current of 1.75 A/mm and maximum extrinsic transconductance of 0.8 S/mm have been achieved for depletion-mode devices. Enhancement-mode HEMTs have also shown maximum drain current of 1.5 A/mm and maximum extrinsic transconductance of 1 S/mm. The selection of atomic layer deposition aluminum oxide (Al 2 O 3 ) for device passivation enables a two-terminal breakdown voltage of ∼25 V, excellent subthreshold characteristics as well as the pulsed-IV featuring little current collapse for both types of HEMTs. When biased at a drain voltage of 10 V, a first-pass two-stage power amplifier design based on 0.1-µm depletion-mode devices has demonstrated an output power of 1.43 W with 12.7% power-added efficiency at 86 GHz, a level of performance that has been attained previously only by state-of-the-art counterparts based on AlGaN/GaN HEMTs at a much higher drain bias and compression level.

We report successful development of an advanced no-field-plate AIGaN/GaN high electron mobility transistors (HEMTs) for millimeter-wave (MMW) applications. The HEMT adopts a reduced source-drain spacing of 2 J.1m and the 0.2-J.1m gate is placed 0.5 J.1m off the source electrode. Additionally, the devices and monolithic microwave integrated circuits (MMICs) are fabricated on the SiC substrate of 2mil, enabling the fabrication of 15 J.1m x 25 J.1m slot via holes for realizing low inductance and more compact devices to facilitate MMW MMIC design. As a result, the narrow band MMICs have achieved an output power of 10.4 W with associated power added efficiency (PAE) of 31% at 28 GHz, and 10.7W and 27% at 36 GHz, respectively. Besides, a state-of-the-art 2-stage single-ended wideband MMIC demonstrates output power of 5-7.9 Wand associated PAE of 13-21 % from low K-band to high Ka-band.

This paper reviews recent progress in the development of GaAs metamorphic HEMT (MHEMT) technology for microwave applications. Commercialization has begun, while efforts to further improve performance, manufacturability and reliability continue. We also report the first multi-watt MHEMT MMIC power amplifiers, demonstrating up to 3.2W output power and record power-added efficiency (PAE) a t Ka-band.

No abstract