A 0.15-μm 60-GHz high-power composite channel GaInAs/InP HEMT with low gate current

This letter presents recent improvements and experimental results provided by GaInAs/InP composite channel high electron mobility transistors (HEMT). The devices exhibit good dc and rf performance. The 0.15-μm gate length devices have saturation current density of 750 mA/mm at V/sub GS/=+0 V. The Schottky characteristic is a typical reverse gate-to-drain breakdown voltage of -8 V. Gate current issued from impact ionization has been studied in these devices, in the first instance, versus drain extension. At 60 GHz, an output power of 385 mW/mm has been obtained in such a device with a 5.3 dB linear gain and 41% drain efficiency which constitutes the state-of-the-art. These results studied are the first reported for a composite channel Al/sub 0.65/In/sub 0.35/As/Ga/sub 0.47/In/sub 0.53/As/InP HEMT on an InP substrate.