characterizinggg electromagnetic properties of...
TRANSCRIPT
Characterizing Electromagnetic g gProperties of Materials
at 110GHz and Beyondat 110GHz and Beyond
Jeffrey Hesler Virginia Diodes Inc.Shelley Begley Agilent TechnologiesSuren Singh Agilent TechnologiesPhil Bartley IMSPhil Bartley IMS
Making Reliable Measurementsat mm and Sub-mm Wavelengths
Agenda
C ?•Why Characterize Material Properties?•Measurement System•Calibration•Measurement Results
Making Reliable Measurementsat mm and Sub-mm Wavelengths
Electromagnetic Materials
Radar Absorbing and Stealth MaterialsRadome MaterialsRadome MaterialsElectronic Substrate and Packaging MaterialsSpecific Absorption Rate (SAR) PhantomsMeta-materialsMeta materials
Making Reliable Measurementsat mm and Sub-mm Wavelengths
Why Materials Characterization?
Characterizing Electromagnetic Properties of Materials at 110GHz and beyond
Important for:Circuit designMilitary ApplicationsCar Radar ApplicationsNew Materials ResearchIncoming InspectionIncoming Inspection Quality AssuranceHealth and Safetyand moreand more…
Making Reliable Measurementsat mm and Sub-mm Wavelengths
Permittivity and Permeability
Permittivity Permeability
Definitions
"' jμ"' jε
Permittivity (Dielectric Constant)
Permeability
0rr jμμ
μμμ −==
0rrr jεεε
εκ −===
interaction of a material in the presence of an external electric field.
interaction of a material in the presence of an external magnetic field.
Making Reliable Measurementsat mm and Sub-mm Wavelengths\
Electromagnetic Field Interaction
Electric MagneticFieldsFields
STORAGE
Permittivity Permeability
Fieldse ds
MUT
LOSS
"'rrr jμμμ −="'
rrr jεεε −=STORAGE
Dielectric ConstantLOSS
Making Reliable Measurementsat mm and Sub-mm Wavelengths
Loss Tangent
ε''
rε
'"tan '
"
κκ
εεδ ==
r
rrε
'ε εr
CycleperLostEnergy1
rε
CycleperStoredEnergyCycleperLostEnergy
QD ===
1tanδ
Dissipation Factor Quality FactorD Q
Making Reliable Measurementsat mm and Sub-mm Wavelengths
Measurement Techniques
Loss
vs. Frequency and Material Loss
Coaxial ProbeHigh
Parallel Plate
Transmission line
Medium Free SpacePlate
FrequencyResonant CavityLow
50 MHz 20 GHz 40 GHz 60 GHz5 GHz 750+ GHz
Making Reliable Measurementsat mm and Sub-mm Wavelengths
MicrowaveRF mm/Submm-wave
Transmission Free-Space
Material assumptions:• Flat parallel faced samplesMaterial assumptions:• Flat parallel faced samples• Flat parallel faced samples• Sample in non-reactive region• Beam spot is contained in sample• Known thickness > 20/360
• Flat parallel faced samples• Sample in non-reactive region• Beam spot is contained in sample• Known thickness > 20/360Known thickness 20/360Known thickness 20/360
l
Reflection(S11 )
Transmission(S21 )
Making Reliable Measurementsat mm and Sub-mm Wavelengths
mm-Submm Wave System
Agilent PNA-X dual source network
analyzeranalyzer
Sample in holderVirginia Diodes Inc Sample in holder between two antennae
Agilent Materials Measurement Software
Virginia Diodes Inc. Transmit and Receive
(TR) Frequency Extenders
Making Reliable Measurementsat mm and Sub-mm Wavelengths
with Free Space Calibration
mm-Submm Wave System Photo
Making Reliable Measurementsat mm and Sub-mm Wavelengths
mm-Submm Wave System Photo
Making Reliable Measurementsat mm and Sub-mm Wavelengths
VDI Frequency Extenders & Horns
VDI offers frequency yextenders from 75GHz through 750GHz with outstanding dynamic range.
Making Reliable Measurementsat mm and Sub-mm Wavelengths
PNA-X mmWave Setup
Making Reliable Measurementsat mm and Sub-mm Wavelengths
Calibration is Required
Before a measurement can be made, a calibration must be performed to remove systematic errors.
Making Reliable Measurementsat mm and Sub-mm Wavelengths
TRM Calibration
Thru
Reflect
MatchMatch
Making Reliable Measurementsat mm and Sub-mm Wavelengths
TRL Calibration
Thru
ReflectMove the antenna away to compensate for the thickness of the short. Move it back for the next step
Line
step.
Move the antenna away on a quarter-wavelengthLine on a quarter-wavelength and then back in the original position.
Making Reliable Measurementsat mm and Sub-mm Wavelengths
Gated Reflect Line (GRL) Calibration
T t lib ti t id i t i t t
Two Tiered Calibration
Two port calibration at waveguide or coax input into antennas removes errors associated with network analyzer and cables.
ECal, SOLT or TRL Cal done here
Making Reliable Measurementsat mm and Sub-mm Wavelengths
Gated Reflect Line (GRL) Calibration
T dditi l f lib ti t d d
Two Tiered Calibration
•Two additional free space calibration standards remove errors from antennas and fixture.
Line (empty fixture)
Reflect (metal plate of known thickness)
Making Reliable Measurementsat mm and Sub-mm Wavelengths
GRL Cal Error Model
2-port Cal Terms 2-port Cal TermsMUT
forward only
p p
D Ms
Tt
Ml
1
S11 S22
S21
GRL Error Adapter
GRL Error Adapter
•Coax or Waveguide 2-port Cal corrects errors from end of cable back into
Tr S12
Adapter Adapter
g pthe instrument.
Making Reliable Measurementsat mm and Sub-mm Wavelengths
GRL Cal Error Model
2-port Cal Terms 2-port Cal TermsMUT
forward only
p p
D Ms
Tt
Ml
1
S11 S22
S21
GRL Error Adapter
GRL Error Adapter
•Coax or Waveguide 2-port Cal corrects errors from end of cable back into
Tr S12
Adapter Adapter
g pthe instrument.
•Errors from Antennas and Fixture can be thought of as being lumped into a GRL error adapter.
•The GRL error adapter is quantified by measurements of reflect and line standards.
Making Reliable Measurementsat mm and Sub-mm Wavelengths
GRL Cal Error Model
MUT
S11 S22
S21
T22 T11
T12
O11 O22
O21
S12 T21O12
Six Unknowns
O21 = O12 T21 = T12Need ThreeO11
O22
T11
T22
Need Three Standards!
Making Reliable Measurementsat mm and Sub-mm Wavelengths
Gated “Standard”
0.00
S11 Time Domain - Empty Fixture3201 points used to avoid aliasing
Mi P i t 1 Ali F R ( ) * F S (H )
-30.00
-20.00
-10.00
time domain gate includes only reflections
before sample
Min Points = 1 + Alias Free Range (s) * Frequency Span (Hz)
-60.00
-50.00
-40.00
Mag
(S) (
dB)
-90.00
-80.00
-70.00
Transmitting Antenna
Receiving Antenna
-100.00-2.00 0.00 2.00 4.00 6.00 8.00 10.00
Time (ns)
S11 (dB) Linear (S11 (dB))
Antenna Antenna
sample holder
Making Reliable Measurementsat mm and Sub-mm Wavelengths
S11 (dB) Linear (S11 (dB))
GRL Cal Error Model
MUT
S11 S22
S21
T22
T12
O22
O21
S12 T21O12
Four Unknowns
O21 = O12 T21 = T12
O22 T22
Making Reliable Measurementsat mm and Sub-mm Wavelengths
Metal Plate Standard
P11 = P22 = -1 MUT
S21 T12O21
P21=P12=0. S11 S22
S12
T22
T21
O22
O12
21 12plate_1
22
O O1 O
Γ = −+
21 12plate_2
T T1 T
Γ = −+ 221 T+
Making Reliable Measurementsat mm and Sub-mm Wavelengths
Line Standard
A11=A22=0 MUT
S21 T12O21
A21 = A12 =
ω= frequency
j ude ω ε−S11 S22
S12
T22
T21
O22
O12ε= permittivity of airμ= permeability of air.d= thickness of the metal plate
21 12 21 12 22air_1
22 22
A A O O T1 O T
Γ =−
21 12 21 12 22air_2
22 22
A A T T O1 T O
Γ =−
Making Reliable Measurementsat mm and Sub-mm Wavelengths
22 22
GRL Cal Error Model
2-port Cal Terms 2-port Cal TermsMUT
forward only
p p
D Ms
Tt
Ml
1
S11 S22
S21
GRL Error Adapter
GRL Error Adapter
Calibration planes are at the surface of
•Coax or Waveguide 2-port Cal corrects errors from end of cable back into
Tr S12
Adapter Adapterthe metal plate.
g pthe instrument.
•Errors from Antennas and Fixture can be thought of as being lumped into a GRL error adapter.
•The GRL error adapter is quantified by measurements of reflect and line standards.
•The original 2-port Cal is modified to correct for the error adapter.
Making Reliable Measurementsat mm and Sub-mm Wavelengths
Transmission Models
Algorithm Measured S-parameters Output
Nicolson-Ross S11,S21,S12,S22 εr and μr
NIST Precision S11,S21,S12,S22 εr
F t S21 S12Fast S21,S12 εr
Poly Fit S11 S21 S12 S22 ε and μPoly Fit S11,S21,S12,S22 εr and μr
Stack Two S21,S12 (two samples) εr and μr
Making Reliable Measurementsat mm and Sub-mm Wavelengths
, ( p ) εr a d μr
Measurement Results
Making Reliable Measurementsat mm and Sub-mm Wavelengths
Measurement Results
Making Reliable Measurementsat mm and Sub-mm Wavelengths
Measurement Results
Multiple solutions can occur when sample is thicker
than 1 wavelength
The correct solution is obtained byis obtained by
giving a permittivity estimate
Making Reliable Measurementsat mm and Sub-mm Wavelengths
sample is 2.36mm thick
Measurement Results
Making Reliable Measurementsat mm and Sub-mm Wavelengths
Future Work
T i ith Th K ti h d f Q i• Try again with Thomas Keating horns made for Quasi-optical table.
• Method for determining number phase rotations in sample.
• Model for low loss samples.
Making Reliable Measurementsat mm and Sub-mm Wavelengths
Thank You
Making Reliable Measurementsat mm and Sub-mm Wavelengths
References
R N Clarke (Ed.), “A Guide to the Characterisation of Dielectric Materials at RF and Microwave Frequencies,”Published by The Institute of Measurement & Control (UK) & NPL, 2003
J B k J i M D J i R F Riddl R T J h k P K b C H ll R G G C A GJ. Baker-Jarvis, M.D. Janezic, R.F. Riddle, R.T. Johnk, P. Kabos, C. Holloway, R.G. Geyer, C.A. Grosvenor, “Measuring the Permittivity and Permeability of Lossy Materials: Solids, Liquids, Metals, Building Materials, and Negative-Index Materials,” NIST Technical Note 15362005
“Test methods for complex permittivity (Dielectric Constant) of solid electrical insulating materials at microwave frequencies and temperatures to 1650° ” ASTM Standard D2520 American Society for Testing and Materialsfrequencies and temperatures to 1650 , ASTM Standard D2520, American Society for Testing and Materials
“Basics of Measuring the Dielectric Properties of Materials”. Agilent application note. 5989-2589EN, April 28, 2005
Deepak K. Ghodgaonkar et al; “Free Space Method for Measurement of Dielectric Constants and Loss Tangents at Microwave Frequencies”; IEEE Transactions on IM volume 37 number 3 June 1989Microwave Frequencies ; IEEE Transactions on IM volume 37 number 3, June 1989.
P. Bartley, S. Begley, “Improved Free-Space S-Parameter Calibration” IMTC 2005 – Instrumentation and Measurement Technology Conference Ottawa, Canada, 17-19 May 2005
Making Reliable Measurementsat mm and Sub-mm Wavelengths