B. BOUDJELIDA1 UMan LNA Programme 4 th SKADS Workshop, Lisbon, 2-3 October 2008 University of Manchester: Progress on LNA Programme B. Boudjelida, A. Sobih, A. Bouloukou, S. Arshad, S. Boulay, J. Sly and M. Missous School of Electrical and Electronic Engineering University of Manchester

B. BOUDJELIDA2 UMan LNA Programme 4 th SKADS Workshop, Lisbon, 2-3 October 2008 OUTLINE Introduction LNA Elements Modelling (pHEMTs and passives) Noise measurements LNA Results MMIC using InP (RF + noise) MIC using off-the shelves components (AVAGO + NEC transistors) Noise predictions for next LNA Conclusions ~ 5 cm pHEMTs Resistors Capacitors Inductors ~ 1 mm

B. BOUDJELIDA3 UMan LNA Programme 4 th SKADS Workshop, Lisbon, 2-3 October 2008 Workflow at University of Manchester Parameter extraction & device modelling Material growth Material assessment Process set-up and fabrication DC & RF measurements LNA circuit design LNA building blocks library LNA Fabrication! Process set-up LNA testing Noise measurements LNA layout design LNA Measurement Introduction

B. BOUDJELIDA4 UMan LNA Programme 4 th SKADS Workshop, Lisbon, 2-3 October 2008 LNA Elements Modelling: passives and pHEMTS For all passives, good “scalable” models successfully obtained as a function of physical parameters 4 x 200 µm (XMBE109-Run1) V p = -1.3 eV Gm = 300 mS/mm F t ~ 30 GHz F max ~ 35 GHz Good agreement between linear, non-linear and measured data.

B. BOUDJELIDA5 UMan LNA Programme 4 th SKADS Workshop, Lisbon, 2-3 October 2008 LNA Elements InGaAs/InAlAs pHEMTs Noise Measurements For better noise, the devices MUST be biased at low VDS  good for power dissipation! XMBE109 – 4x200 μm device: Noise figure in a 50Ω system at different bias points (Freq=1GHz).  VDS=1V : NF50 ~ 1dB (lower for higher current)  Lowest NF for lower VDS : WHY?  Gate leakage due to impact ionization!

B. BOUDJELIDA6 UMan LNA Programme 4 th SKADS Workshop, Lisbon, 2-3 October NFmin (dB) Frequency (GHz) LNA Elements InGaAs/InAlAs pHEMTs Noise Measurements Independent Lab: MC2 (spin-off IEMN Lille) XMBE109 – 4x200 μm device: Minimum noise figure extracted from the “F50” method. Extraction of the noise parameters relies on the equivalent circuit. NFmin ~ 0.5 1GHz VDS=1V; 10%IDSS

B. BOUDJELIDA7 UMan LNA Programme 4 th SKADS Workshop, Lisbon, 2-3 October Frequency (GHz) NFmin (dB) LNA Elements InGaAs/InAlAs pHEMTs Noise Measurements Independent Lab: MC2 (spin-off IEMN Lille) XMBE109 – 4x200 μm device: Minimum noise figure measured using the multi-impedance method (tuner). Measurement independent of the equivalent circuit! Expensive… requires accurate tuners. NFmin ~ GHz !! This method is believed to give more accurate results BUT the “true” NFmin is likely to lie between the 2 measurement methods.  NFmin ~ 0.2 1GHz VDS=1V; 10%IDSS

B. BOUDJELIDA8 UMan LNA Programme 4 th SKADS Workshop, Lisbon, 2-3 October 2008 Transistor biased at 20% IDSS (VD = 1V ; ID~40 mA) LNA circuit No input inductor, use of large resistor, parameters optimized for best performance Ld series resistance + Rb are used for biasing the drain Comments: GSG - 100μm pitch probes LNA layout GSG - 100μm pitch probes Fabricated LNA LNA Results InP MMIC design, fabrication and measurement

B. BOUDJELIDA9 UMan LNA Programme 4 th SKADS Workshop, Lisbon, 2-3 October 2008 LNA Results InP MMIC RF and Noise results Discrepancies with noise highly likely to be due to NiCr resistors process Could also be due to measurement issues (no decoupling probes for DC feed)

B. BOUDJELIDA10 UMan LNA Programme 4 th SKADS Workshop, Lisbon, 2-3 October 2008 LNA Results MIC design, fabrication and measurement NEC transistors, Double-stage circuit, optimised for GHz operation Goals:  Demonstrate the validity of the model predictions  “Easy-to-assemble” using commercial off the shelves components  Could be used for demonstrators such as 2PAD

B. BOUDJELIDA11 UMan LNA Programme 4 th SKADS Workshop, Lisbon, 2-3 October 2008 LNA Results MIC design, fabrication and measurement 8 different LNAs designed using NEC and Avago transistors Single and double-stage circuits being measured now!  Very good noise predictions! NF < 0.6 dB !

B. BOUDJELIDA12 UMan LNA Programme 4 th SKADS Workshop, Lisbon, 2-3 October 2008 LNA circuit Input bias and impedance match off-chip L series resistances used for drain biasing Comments: LNA Results InP MMIC predictions

B. BOUDJELIDA13 UMan LNA Programme 4 th SKADS Workshop, Lisbon, 2-3 October 2008 LNA Results InP MMIC predictions NF< 0.35 dB from 0.3 to 1.6 GHz

B. BOUDJELIDA14 UMan LNA Programme 4 th SKADS Workshop, Lisbon, 2-3 October 2008 Conclusions The first full MMIC LNA successfully modelled, fabricated and tested The measured NF in the 50Ω system is also higher than what predicted by the simulations  due to Resistors (under investigation, 2 nd MMIC run under way) Still very good agreement between measurement and models using the equivalent circuit models MMIC The first fabricated MICs yield measured NF as low as 0.6 dB (~42K) Super low noise InGaAs/InAlAs pHEMTs technology demonstrated NFmin < 0.2 1GHz using the 1 µm gate geometry Noise predictions demonstrated MIC Next LNA expected to go below 0.35 dB (25K) at RT in a 50Ω system between 0.3 to 1.6 GHz