Two-Finger InP HEMT Design for Stable Cryogenic Operation of Ultra-Low-Noise Ka-and Q-Band LNAs

• We investigate the cryogenic stability of two-finger 100-nm gate-length InP HEMTs aimed for Ka-and Q-band ultra-low noise amplifiers (LNAs). InP HEMTs with unit gate widths ranging between 30 and 50 mu text{m} exhibit unstable cryogenic behavior with jumps in drain current and discontinuous peaks in transconductance. We also find that shorter gate length enhances the cryogenic instability. We demonstrate that the instability of two-finger transistors can be suppressed by either adding a source air bridge, connecting the back end of gates, or increasing the gate resistance. A three-stage 24-40 GHz and a four-stage 28-52-GHz monolithic microwave-integrated circuit LNA using the stabilized InP HEMTs are presented. The Ka-band amplifier achieves a minimum noise temperature of 7 K at 25.6 GHz with an average noise temperature of 10.6 K at an ambient temperature of 5.5 K. The amplifier gain is 29 dB ± 0.6 dB. The Q-band amplifier exhibits minimum noise temperature of 6.7 K at 32.8 GHz with average noise temperature of 10 K at ambient temperature of 5.5 K. The amplifier gain is 34 dB ± 0.8 dB. To our knowledge, the Ka-and Q-band amplifiers demonstrate the lowest noise temperature reported so far for InP cryogenic LNAs. © 1963-2012 IEEE.

Ämnesord

TEKNIK OCH TEKNOLOGIER  -- Elektroteknik och elektronik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Electrical Engineering, Electronic Engineering, Information Engineering (hsv//eng)

Nyckelord

cryogenics

InP HEMT

low-noise amplifier (LNA)

monolithic microwave-integrated circuit (MMIC)

stability

wideband

Chromium compounds

Convergence of numerical methods

Drain current

High electron mobility transistors

III-V semiconductors

Indium compounds

Indium phosphide

Logic gates

Microwave integrated circuits

Monolithic integrated circuits

Monolithic microwave integrated circuits

Semiconducting indium

Semiconducting indium compounds

Semiconducting indium phosphide

Semiconductor materials

Temperature

Transconductance

Cryogenic operations

Cryogenic stability

Gate resistance

Monolithic microwave integrated circuits (MMIC)

Noise temperature

Ultra low noise

Wide-band

Low noise amplifiers

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)