Multimaterial Additive Manufacturing of ......Novel Additive Manufacturing (AM) Methods • Quad deposition heads • Material Agnostic via micro-dispensing print heads • Prints

UNCLASSIFIED 3D-PEIM, June 25th , 2018 UNCLASSIFIED

Multimaterial Additive Manufacturing of Radiofrequency Devices and Systems

Professor Mark S. Mirotznik Department of Electrical and Computer Engineering

University of Delaware


State of the Art

What we want What we usually end up with


The state of the art is somewhere in between, and isn’t necessarily applicable to large volume production.


Where is the application space for AM printed RF systems?


1. Small Volume – Labor intensive parts or systems


Where is the application space for AM printed RF systems?

2. Complex geometrical structures

Conformal RF electronics 3D Graded Material Properties



Where is the application space for AM printed RF systems?3. Point-of-need manufacturing



What are the major challenges?

1. Materials – We think the development of new AM materials that possess good RF, mechanical, thermal, … properties is the biggest current challenge

Some Material Challenges(1) RF conductivities



2. Multimaterial AM printing systems – For complex electronic systems moving parts between multiple printing systems is not ideal. Our goal is the print a part from start to finish on a single system.




3. Quality control – AM systems typically run open loop often leading to failed parts (and sometimes failed printers).



Material Development

q CNT based resistive inkq Magnetic inksq High permittivity inksq High conductivity inksq Quantum dot inks

Additive Manufacturing Methods

q Multi-material AM

q Structural composite integration

Multi-physics modeling and design of electromagnetically functionalized

structural composites

Applicationsq Graded Dielectrics

q Conformal load bearing antennas

q RF Antennas and Electronics

q Chemical sensing

Additive Manufacturing of Multifunctional RF Devices and Systems



Novel Additive Manufacturing (AM) Methods

• Quad deposition heads• Material Agnostic via micro-

dispensing print heads• Prints viscosities from 1-1 million cp• Volumetric dispense control down

to 100 picoliters• Line sizes ~25-500 μm• Ability to print on conformal

surfaces via integrated laser scanning

• Ability to print thermoplastics (FDM)• Positional control down to 1μm

nScrypt 3Dn-300



Novel Additive Manufacturing (AM) Methods





q Multi-material AM







q Chemical sensing




Material Development: Inks and Pastes

Magnetically Loaded Inks High Permittivity Inks

Magnetodielectric Powder: Custom synthesized 20nm ferrite particles

+

Sample µr tanδm εr tanδeFe3O4 (10% vol.) 1.3 0.08 3.1 0.001Fe3O4 (20% vol.) 1.8 0.11 3.8 0.08Fe3O4 (30% vol.) 2.1 0.12 4.6 0.09Fe3O4/EPON (40% vol.) 2.4 0.13 6.2 0.11Ni0.5Zn0.5Fe2O4(20% vol.) 1.9 0.10 3.5 0.10Ni0.5Zn0.5Fe2O4 (30% vol.) 2.5 0.12 3.8 0.15

Barium Titanate Powder: 1-3 µm particle sizes

+

Polymer Resin and catalyst

Sampleµr tanδm εr tanδe

BaTiO3 (20% vol.) 1.0 0 9.6 0.006BaTiO3 (30% vol.) 1.0 0 16.7 0.02BaTiO3 (40% vol.) 1.0 0 23.0 0.03BaTiO3 (50% vol.) 1.0 0 36.8 0.04

* Measure from 16-27 GHz* Measure from 100-600 MHz

Polymer Resin and catalyst


Material Development: Inks and PastesResistive Inks Metallic Inks

Carbon black powder

Polymer matrix

Carbon nanotubes

+

+

q Attractive EM loss propertiesq Nice viscosity for AM printingq Low costq No volatiles

Additive ManufacturingMaterial Development Effort

q Silver flakes + Silver nano-particlesq No organic binderq Potential for near bulk metallic propertiesq Been used for printable RF transmission lines and

antennasq Adjustable viscosities


Material Development: Inks and PastesFluorescent Inks


q Quantum dots + hydrophilic resinq Design inks that adhere to a wide range of

surfaces: Clothing/Fabrics, Leather, Metal, Plasticsq Potential use for anti-tampering applications.

Under ambient lightThe printed array of squares is

largely transparent.Under UV light illuminationThe array of printed squares

are fluorescent.

Active Phase Changing Inks

Vanadium oxide (VO2)

0 10 20 30 40 50 60 70 80 900

50

100

150

200

250

300

350

400

450

Res

istiv

ity (

Ohm

s)

Time (seconds)


Material Development: Inks and Pastes

Chemiresistive Inks



Material Development: Custom Polymer Filaments


Fused Deposition Modeling (FDM) extrudes melted thermoplastic filaments




Polymer powder AdditivesCustom filaments

Print using FDM

ThermoFisher Process 11 Twin Screw Polymer Extruder



Low Dielectric Constant Filaments (eer3.0)


Barium Titanate Additivewithin a Polypropylene Matrix

At higher volume fractions of BaTithe filaments turn brittle

(consistency of hard spaghetti)

FDM printable**

*

* - measured data


Material Development: Custom Polymer FilamentsHigh Dielectric Constant Filaments (eer>3.0)






q Multi-material AM







q Chemical sensing



RF Systems




Printed Antennas

Conformal Antennas

q Ku-band 4 element patch arrayq The entire antenna was fully printed using the

nScrypt systemq Materials used were silver ink and polycarbonate

substrate



Printed Antennas

Conformal Antennas

q Ku-band 4 element patch arrayq The entire antenna was fully printed using the

nScrypt systemq Materials used were silver ink and polycarbonate

substrate



Printed AntennasVery Small Antennas

Dielectric

Metal

Metal

Smallest feature size is 25 µµm

5mm

Fully 3D Printed Quadrupole Antenna

Designed by MITRE Corporation



Printed RF Transmission Lines

Grounded co-planar transmission line

50 mm


Additive Manufacturing of Multifunctional RF

Devices and Systems

Printed RF Transmission Lines

Attenuation coefficient (dB/cm) f=12 GHz f=15 GHz f=18 GHz

Printed grounded co-planar waveguide 0.29 0.34 0.36

Printed microstrip transmission line 0.32 0.36 0.37

Transmission Coefficient

50 mm

Grounded co-planar

transmission line



Printed RF Connectors

12 13 14 15 16 17 18-50

-40

-30

-20

-10

0

Frequency (GHz)

S11 (

dB

)

Measured Return LossSimulated Return Loss

Edge Mount Connectors Return Loss



Printed RF Connectors

12 13 14 15 16 17 18

-40

-30

-20

-10

0

Frequency (GHz)

S11

(dB

)

MeasuredSimulated

Face Mount ConnectorsReturn Loss


Additive Manufacturing of Multifunctional RF

Devices and Systems

Integration of Active Components

» Explore Automatic Placing Active Components:» Making Reliable Connections/Bonds

» Demonstrate Biasing Networks:» Push Pin Connections

» Explore Power Handling capabilities.

Avago AMMP-6408

6 to 18GHz 1W Power Amp

Printed

connectors



Integration of Active Components

» Explore Automatic Placing Active Components:» Making Reliable

Connections/Bonds» Demonstrate Biasing

Networks:» Push Pin Connections

» Begin Exploring Power Handling capabilities.

Goals:





q Multi-material AM







q Chemical sensing



3D Printed Graded Dielectrics

34

Fabricate complex 3D geometries in which the electrical

properties (e.g. dielectric constant) vary nearly arbitrarily

in three dimensions

),,( zyxe

x

yz

Goal

UNCLASSIFIED 3D-PEIM, June 25th , 2018 UNCLASSIFIED 35

( )2

2÷øö

çèæ+-=hhWhAcross p

hLAVF totcross×L×

= 2( )

L

+×÷ø

öçè

æ÷øö

çèæ --

=1

41 NhW

VF

p

micro-CT scan of printed space filling curve

Use of Space Filling Curves


Volume fraction of printed material per unit cell


Lens

Port 1 Antenna

Sample

RAMPort 2 Antenna

Lens

Use of Space Filling Curves: Dielectric Materials


Material: Polycarbonate



Example Applications: Passive Beam Steering

Phased array technology is powerful but can be expensive and have limited operational bandwidths

Passive beam steering/switching can be a lower cost and wider bandwidth alternative to phased arrays.



Example Applications: Luneburg Lens3D Luneburg Lens Beamformer

-r

0

r -r

0

r

-r

0

r

1

1.1

1.2

1.3

1.4

1.5

1.6

1.7

1.8

1.9

2

2

2)( ÷øö

çèæ-=Rrre



Modified Luneburg Lens

Quasi-Conformal Transformation Optics

det

Tee L L¢ =L

jjj

xx

¢¢ ¶L =

¶det

Tµµ L L¢ =L



Modified Luneburg Lens

-r

0

r -r

0

r

-r

0

r

1

1.1

1.2

1.3

1.4

1.5

1.6

1.7

1.8

1.9

2

Quasi-Conformal Transformation Optics



Modified Luneburg LensQuasi-Conformal Transformation Optics

Fabricated Luneburg Lens using FDM Printing

Made from polycarbonate (eer=2.7)



Example Applications: Luneburg Lens

Fabricated Luneburg Lens using 3D Printing

26-40 GHz

8-18 GHz

26-40 GHz

60-110 GHz



26 GHz

Modified Luneburg Lens (Ka-band 26 GHz – 40 GHz)



W-Band Luneburg Lens (70-110 GHz)

Fabricated W-band Luneburg Lens using FDM printing with a 50 µµm

Human hair

25 µm nozzle

Z. Larimore, S. Jensen, A. Good, J. Suarez and M.S. Mirotznik, “Additive Manufacturing of Luneburg Lens Antennas Using Space-Filling Curves and Fused Filament Fabrication”, IEEE Transactions on Antennas and Propagation, May 2018.



W-Band Luneburg Lens (70-110 GHz)70 GHz

110 GHz



Work in Progress: Luneburg Lens Array at 30 GHz





q Multi-material AM







q Chemical sensing




Example Applications: Chemical Sensors

Goal of this project to fabricate fully functional chemical sensors that can be integrated into conformal surface using multi-material/multi-functional additive manufacturing.



Example Applications: Chemical Sensors

Concept: Fully 3D integrated sensor for detection of multiple analytes



Example Applications: Chemical SensorsMaterial Development



Example Applications: Chemical SensorsElectronics Integration



Example Applications: Chemical SensorsAdditive Manufacturing



Example Applications: Chemical SensorsAdditive Manufacturing


Questions/Acknowledgments

A PORTION OF THIS WORK WAS CARRIED OUT UNDER SBIR CONTRACT #W31P4Q-16-C-0110 IN

COLLABORATION WITH U.S. ARMY AMRDEC

THE AUTHORS WOULD LIKE TO ACKNOWLEDGE FUNDING SUPPORT FOR A

PORTION OF THIS WORK FROM THE OFFICE OF NAVAL RESEARCH.

Students and Collaborators:ØZach Larimore, Ph.D. candidate UDEL Dept. of ECEØPaul Parsons, Ph.D. candidate UDEL Dept. of ECEØAustin Good, Ph.D. candidate, UDEL Dept. of ECEØSarah Jensen, Ph.D candidate, UDEL Dept. of ECEØDr. Shridhar Yarlagadda, UDEL Center for Composite MaterialsØLarry “LJ” Holmes, Assistant Director of Additive Manufacturing, UDELØPaul Ransom, Ph.D., NSWCCDØJonathan Kruft, NSWCCDØDr. Peter Pa, Ph.D. UDEL Dept. of ECE (now at LEIDOS)ØMathew Mills, M.S. UDEL Dept. of ECE (now at NSWCCD)

Documents

Multimaterial Additive Manufacturing of ......Novel Additive Manufacturing (AM) Methods • Quad deposition heads • Material Agnostic via micro-dispensing print heads • Prints