Astronomical Telescopes and Instrumentation (SPIE) 8/28/021 Centro Astronómico de Yebes, Obs....

Astronomical Telescopes and Instrumentation (SPIE) 8/28/02

1Centro Astronómico de Yebes, Obs. Astronómico Nacional, IGN (Spain)

Wide band, ultra low noisecryogenic InP IF amplifiers

for the HERSCHEL mission radiometers

Isaac López-Fernández, Juan Daniel Gallego, Carmen Diez, Alberto Barcia, Jesús Martín-Pintado

Centro Astronómico de YebesObservatorio Astronómico Nacional

Guadalajara, SPAIN



Outline

Introduction Device characterization Amplifier design Amplifier fabrication Amplifier performance

Noise and gain measurements Reflection and stability measurements Gain fluctuations measurements Isolator measurements

Conclusions



Introduction: HERSCHEL requirements

HERSCHEL: Far Infrared and Submillimeter 3.5 m Telescope orbiting in L2 with 3 cryogenic instruments

HIFI: Heterodyne Instrument for the Far Infrared with 7 dual polarization submillimeter SIS and HEB receivers

Our contribution: low noise, wide band 4-8 GHz cryogenic IF preamplifiers for each mixer channel (14)

Sensitive parameters: Noise temperature: the contribution to the receiver noise is

significant Power dissipation: mission life limited by liquid helium mass Gain fluctuations: impact in the chopping frequency Other mechanical and electrical constraints



Introduction: CAY experience

More than 150 cryogenic LNAs built for different applications(not including to HERSCHEL developments) IRAM: Grenoble, PdB interferometer, 30m (IF amplifiers) ESOC: New Northia DSN antenna (Rosetta, SMART) Burdeos Observatory EMCOR (Atmospheric sensing) PRONAOS (mm receiver in stratospheric balloon) INPE: 14m Brazil CAY: VLBI receivers (X and K band)

Wide experience with HEMT devices More than 30 batches of commercial GaAs transistors tested Several models of InP transistors measured

JPL-TRW (CHOP program): 14 batches, 9 models ETH Zürich: 7 batches, 4 models Chalmers University: 1 batch



Introduction: Initial developments

Prototypes in the 8 – 12 GHz band Successful testing of InP in this band and comparison with

GaAs results Demonstration of InP in the 4 – 8 GHz band

6 8 10 12 140

5

10

15

20

25

30

YXF 001 Prototype AmplifierT=14 K, not optimized

InP TRW 160 m GaAs Fujitsu FHX13X

Gai

n [d

B]

Freq. [GHz]

0

10

20

30

40

50

60

Tn

[K]



Device characterization: TransistorsMeasurement procedures

InP technology selected based on previous experience in IF amplifiers lower power dissipation, factor of 2 better noise, higher gm

Cryogenic S parameter measurements to model devices In-house test fixture with microstrip lines to allow two-tier TRL calibration Device measured with bonding wires DC and coldFET complete the small signal model

Noise model according to Pospieszalski The noise measured in a wide band test amplifier sets the TD of the model



EXAMPLE OFCRYOGENIC

S PARAMETERS(1 – 40 GHz)

MODEL Circuit modelMEAS Raw dataMEASG Time domain

filter



Device characterization: TransistorsResults

3 4 5 6 7 8 90

5

10

15

20

25

30

YCF 2 InP devices comparisonOptimum noise bias

ETH T-35 TRW T-45 TRW T-42

Ga

in (

dB

)

Freq. (GHz)

0.0

2.5

5.0

7.5

10.0

12.5

15.0

Tn

(K

)

ETH T-35 TRW T-45 TRW T-42

TRW T-42 CRYO3 200×0.1 μm gate Best performance

TRW T-45 CRYO4 200×0.1 μm gate Used in DMs Space qualifiable, to be used in FMs CHOP developed

ETH T-35 200×0.2 μm gate Experimental transistor Design by request Used in MPAs

0.22 mm

0.19

mm



Device characterization: Components

Selection of components based on previous experience at cryogenic temperatures SOTA thick film resistors ATC 111 parallel plate capacitors with CA dielectric ATC 100 multilayer porcelain capacitors RT/Duroid 6002 substrates 20 mils thick

Simple models of concentrated elements are adequate for this frequency range


10

Centro Astronómico de Yebes, Obs. Astronómico Nacional, IGN (Spain)

Amplifier design

Microstrip hybrid design simulated by MMICAD software Developed cryogenic models for transistors, connectors, critical

capacitors, resistors and bonding wires Each InP device is independently stabilized by resistive loading and

inductive feedback Input circuit: wideband noise matching Tuning elements incorporated in the design

(adjustable bonding wires, microstrip islands) Box resonances avoided with careful EM design and the use of

microwave absorbers Multiple bias networks requirements

Contribute to the unconditional stability of the amplifier Comply with EMC mission requirements Provide ESD protection of sensitive InP HEMTs Have a low drain voltage drop Filter RF


11


Amplifier fabrication: several series

37 4-8 GHz YCF amplifiers fabricated at CAY in different series All processes performed in our labs Design transferred to Alcatel Espacio to build Flight Models Series analyzed here:

YCF 2 – ETH transistors (Mixer Program Amplifiers) YCF 6 – TRW transistors (Development Models)

SERIES QUANTITY DESTINATION SER. NUMBERS

0 - 1 4 Demonstration prototypes for the evaluation of technology, devices and performance 002, 3, 4, 1001

1 Yebes 2001 1 Platform for transistor characterization (Yebes) 2010 8 Herschel MP (SRON, JPL, KOSMA, DEMIRM, Chalmers) 2002-2009 4 IRAM ALMA Development 2013, 16, 17, 18 1 SRON ALMA Development 2015 4 Harvard-Smithsonian CfA (SMA) 2011, 12, 19, 20

2

1 Cambridge Cavendish Laboratory (JCMT) 2014

5 1 Cornell University (Arecibo) 5001 1 Yebes 6001

5 Herschel DMs 6004, 5, 6, 9, 14 4 Herschel MP (SRON, JPL, KOSMA) 6007, 10, 11, 12

6

2 Harvard-Smithsonian CfA (SMA) 6008, 13


12


MP amplifier YCF 2

2 stages ETH 200 µm

Gold plated brass

61.4×35×11.5 mm, 149 g

Duroid 6002 substrates

DM amplifier YCF 6

2 stages TRW 200 µm

Gold plated aluminum

58×32×15 mm, 65 g

Duroid 6002 substrates

Improved bias circuits

Additional cavity for filtering


13


Amplifier fabrication: reliability

Reliability is a priority over performance for the selection of components, substrates and mounting techniques

Spatial design Cryogenic operation

Past experience in cryogenic designs obviates most of the work in testing, modeling and pre-qualifying components

An example: ‘O’ ribbon connection in the SMA tab contact: Allows mobility in three axis Excellent electrical properties

compared with traditional SMA connections


14


Performance: Noise and GainMeasurement procedures

Measurement procedure:Cold attenuator

Two measurement systems available at our labs: System 350:

Older More pessimistic Used to keep traceability with

past measurements All noise tests shown here

were performed with 350. System 1020:

Newer calibration. Gives 0.75 K better results

Estimated error (both) 1.4 K(repetitivity < 0.2 K)

3 4 5 6 7 8 90

5

10

15

20

25

30

YCF 6001 (T=14 K)

System 1020 System 350

Gai

n (

dB)

Freq. (GHz)

0

2

4

6

8

10

12

Tn

(K)

15 K

65 K

297 K

PREAMPLIFIER

DEWAR

HPIBRS-232

NARDA DC-BLOCK

NARDA ATTEN. (15 dB)

HEMT AMPLIFIER

TEMP. SENSOR

LAKE SHORE CRYOGENIC

THERMOMETERCOMPUTER

NOISE FIGURE METER

TEST SET

SYNTHESIZER OSCILATOR

NOISE DIODE HP 346 C


15


Performance: Noise and GainResults

3 4 5 6 7 8 90

5

10

15

20

25

30

Gai

n [d

B]

Freq. [GHz]

0

2

4

6

8

10

12

HERSCHEL IF1 YCF 2 MPsGlobal optimum bias T=14 K

Tn

[K]

3 4 5 6 7 8 90

2

4

6

8

10

12

Tn

[K]

Freq. [GHz]

0

5

10

15

20

25

30

HERSCHEL IF1 YCF 6 DMsP

D=4 mW, T=14 K

Gai

n [d

B]

NOISE TEMPERATURE [K] (MEAN)

GAIN [dB] (MEAN)

GAIN FLATNESS [dB] (PEAK TO PEAK) AMPLIFIER

GROUP Best amp. Average Worst Best amp. Average Worst Best amp. Average Worst

YCF 2 MPAs 4.89 5.18 5.38 25.29 24.80 24.06 2.35 2.85 3.19 YCF 6 DMs 3.46 3.57 3.72 27.70 27.11 26.26 1.96 2.19 2.46

Average of 3.57 K mean noise in the band for the complete DM series


16


Performance: Reflection and Stability

Worst case output reflection Average MPAs: -14.3 dB Average DMs: -13.0 dB

Model prediction of output return losses needs refinement

Isolator at the input(not designed for low input ref.)

Unconditionally stability for most bias points checked with sliding shorts

2 3 4 5 6 7 8 9 10-30

-25

-20

-15

-10

-5

0

Freq. [GHz]

S1

1,

S2

2

[dB

]

HERSCHEL IF1 YCF 2 MPsGlobal optimum bias, T=14 K

2 3 4 5 6 7 8 9 10-30

-25

-20

-15

-10

-5

0

Freq. [GHz]

S1

1,

S2

2

[dB

]

HERSCHEL IF1 YCF 6 DMsP

D=4 mW, T=14 K


17


Performance: Gain fluctuationsCryogenic measurements of DMs (TRW transistors)

Characterized by spectral density of normalized gain fluctuations:1. Measure S21 @ 6 GHz with HP8510 VNA (attenuator and air lines)

2. Normalize and FFT each VNA scan (0.012-2.34 Hz)

3. Average 50 spectra and subtract the system fluctuations Fit, in the region where 1/f noise dominates, the expression

AMPLIFIER YCF

GAIN FLUCT. @ 1HZ ( )

SPECTRAL INDEX (α)

6004 8.62E-05 0.754 6005 8.88E-05 0.706 6006 1.29E-04 0.562 6009 1.00E-04 0.726 6014 1.02E-04 0.762

Average 9.40E-05 0.737

21

)(

fHz

fS β represents the fluctuatons @ 1 Hz and is used as a reference for comparison between amplifiers


18


Performance: Gain fluctuationsCorrelation with voltage fluctuations

Fluctuations of gate voltage measured with HP35670A

Moderate correlation with gain fluctuations for different amplifiers measured at the same bias point

This simple DC measurements may be useful for pre-selecting least fluctuating devices from a batch

8.0x10-5 1.0x10-4 1.2x10-4 1.4x10-44.0x10-5

5.0x10-5

6.0x10-5

7.0x10-5

8.0x10-5

9.0x10-5

YCF 6 amplifiers fluctuations (both stages)8 GHz, 14 K Vd1=0.85 V Vd2=0.5 V Id1,2=3 mA

VG @

1 H

z [V

/Hz1

/2]

G/G @1 Hz [1/Hz1/2]

10-2 10-1 100 10110-5

10-4

10-3

10-2

YCF 6001 Gain fluctuations Spectrum8 GHz, 14 K Vd1=0.85 V Vd2=0.5 V Id1,2=3 mA

G/G

[H

z-1

/2]

Freq. [Hz]

measured fitted correction

1st stage

2nd

stage

100

101

102

10n

100n

1µ

10µ

100µ

1m

10m

YCF 6001 VG fluctuations Spectrum

8 GHz, 14 K, Vd1=0.85 V, Vd2=0.5 V, Id1,2=3 mA

VG [V

/Hz

1/2]

Freq. [Hz]

1 Hz

1 Hz


19


Performance: Gain fluctuationsBias dependence

Tested the variation of gain and voltage fluctuations with drain voltage Found a steep change in gain voltage around 0.5 V The behaviour of gain and voltage fluctuations is similar as Vd varies

High fluctuation zones could be avoided with no penalty in noise or gain Voltage fluctuations may help detecting these bias regions

0.0 5.0x10-5 1.0x10-4 1.5x10-40.0

1.0x10-5

2.0x10-5

3.0x10-5

4.0x10-5

5.0x10-5

YCF 6001 1st stage fluctuations8 GHz, 14 K Vd=0.3..0.7 V Id=3 mA (device)

VG

1 @

10 H

z [V

/Hz

1/2]

G/G @1 Hz [1/Hz1/2]

0.2 0.3 0.4 0.5 0.6 0.7 0.80.00

2.50x10-5

5.00x10-5

7.50x10-5

1.00x10-4

1.25x10-4

1.50x10-4

Gain fluctuations noise floor

YCF 6001 1st stage fluctuations8 GHz, 14 K Id=3 mA

VD1

(device) [V]

G/G

@1

Hz

[1/H

z1/

2]

0.0

1.0x10-5

2.0x10-5

3.0x10-5

4.0x10-5

5.0x10-5

6.0x10-5

VG @

10 H

z [V

/Hz

1/2]


20


Performance: IsolatorsImpact in overall performance

Isolators measured @ 14 K (PAMTECH gives data @ 77 K)

Good agreement between measurement and estimation of isolator noise:

Mean contribution 1.1 – 1.4 K

ampambiso

c TTG

T

1

1

3 4 5 6 7 8 90

5

10

15

20

25

30

YCF 6005 (T=14 K)

Tn

(K)

Freq (GHz)

No Isolator Isolator K10 SN 101

0

5

10

15

20

25

30

G(d

B)


21


Performance: IsolatorsResults

MEASUREMENTS @ 14 K [dB] ISOLATOR MODEL

DATA TYPE S11 < S22 < S12 < S21 >

Gav mean [dB]

ΔTc mean [K]

Best of 9 -19.6 -19.0 -19.6 -0.27 -0.17 0.81

Average -18.8 -18.1 -17.4 -0.36 -0.20 1.12 CTH1365 K4

Worst of 9 -18.2 -17.3 -16.0 -0.46 -0.30 1.48 Best of 5 -18.0 -17.9 -20.7 -0.50 -0.26 1.25

Average -16.2 -15.4 -18.3 -0.58 -0.28 1.38 CTH1365 K10

Worst of 9 -15.0 -14.0 -16.5 -0.66 -0.30 1.47

0 2 4 6 8 10 12-50

-40

-30

-20

-10

0

-5

-4

-3

-2

-1

0

Iso

latio

n [

dB]

Freq. [GHz]

PAMTECH CTH 1365 K10 ISOLATORS (T=15 K)

S12 S21

Lo

sse

s [d

B]

0 2 4 6 8 10 12-50

-40

-30

-20

-10

0PAMTECH CTH 1365 K10 ISOLATORS (T=15 K)

S22 S11

Ref

lect

ion

coef

f. [d

B]

Freq. [GHz]


22


Summary

34 InP HEMT 4-8 GHz cryogenic amplifiers fabricated for HERSCHEL, including the Development Models with TRW transistors

Cryogenic S parameters of InP transistors measured in microstrip and noise models developed

Cryogenic isolators used at the input allow wide-band mixer-independent design with small penalty in noise

Exceptional performance and repeatabilityFor the final DMs 3.5 K noise and 27±1.1 dB gain dissipating 4 mW

Gain fluctuations exhibit a greater dispersion Low frequency noise of gate bias may help selecting more stable devices

High sensitivity of gain fluctuations to bias point Gate bias noise measurements could detect bias regions of high fluctuations

Astronomical Telescopes and Instrumentation (SPIE) 8/28/021 Centro Astronómico de Yebes, Obs....

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Transcript of Astronomical Telescopes and Instrumentation (SPIE) 8/28/021 Centro Astronómico de Yebes, Obs....