0.15 μm gate length MHEMT technology for 77 GHz automotive radar applications

The 0.15 μm gate-length power metamorphic HEMTs (MHEMT) with wide head T-shaped gate has been fabricated and the DC, and microwave performance of the device were characterized. The MHEMT device shows the DC output characteristics having an extrinsic transconductance of 740 mS/mm and a threshold voltage of -0.75 V. The f_T and f_max obtained for the 0.15 μm × 100 μm MHEMT device are 150 GHz and 240 GHz, respectively. A MMIC 77 GHz 3-stage amplifier is reported in this paper. This MMIC chip demonstrated a measured small signal gain of over 12 dB from 70 GHz to 79 GHz with 7 dBm output power at 1 dB compression. The maximum small signal gain is above 13.5 dB from 77 to 78 GHz. This chip is fabricated using 0.15 μm MHEMT process based on 4-inch substrate. This MMIC chip size is 1.7 mm × 2 mm. This MMIC amplifier chip is suitable for the 77 GHz automotive radar systems and related transmitter applications in W-band.