Transcript DoD workshop_PMeso

Electronics Miniaturization
using Fine-Feature
Nanosilver conductors
Fine feature (<10 microns) trace/space
capability
•
•
•
Maximum component density
Fully encapsulated silver conductors
Quick, inexpensive prototyping
Encapsulated component blocks
•
•
•
Rugged/robust
Minimize dead volume
Easy test of subsystems
Low Capital Equipment Costs
1
Nano-silver conductor fabrication
Pulsed
UV laser
Laser ablate channels
5. Full oven cure
1. 1st Squeegee
Fill
4. Residue
removal
2. Low T bake
3. 2nd Squeegee
Fill
Conductor resistivity ~ 3X bulk Ag
Finished circuit
2
Embedded nanoparticle silver
conductors
Embedded conductor
Conventional conductor
• Nanoparticle conductor advantages:
– Eliminate photolithography
– Conductor width limited only by laser focal spot size.
• <10 micron trace/space demonstrated
• Controllable aspect ratio
– Additive, green process
3
Substrates:
Polyimide
•
•
15 micron traces
Two sides with via
•
ABF
•
LCP
•
MicroLam
•
Mylar
•
Alumina
Stretchable
conductors
Embedded
conductor
Polyimide
Quasi-conformal circuitry
Stretchable circuits connect miniature
modules
• Wearable sensors
• Conform to irregular shapes
Embedding in elastic polymer
Sensor
MCU
6
Fine pitch
coil on 1 mm
tube
High packing density
0201 resistors
> 1000 components/cm3
8
Narrow traces reduce
layer count and cost
Nanosilver
•2 layers
•15 to 30 micron traces
•$1000 for first 10 substrates
•1 day turnaround
Conventional copper
•4 layers
•75 micron traces
•$7800 for first 10 substrates
•12 day turnaround
8 mm
12 mm
9
• Miniature systems using
readily available SMT
components
• Low cost ASIC equivalent
• Adaptable to
prototyping/low volume
production
• Simple manufacturing
scale-up
Miniature module fabrication
1. Encapsulate components
2. Fabricate fine feature interconnects on thin substrates
•
Nanoparticale silver conductors
•
Laser direct-write processes
3. Connect components using conductive adhesives
11
Component Encapsulation
SMD
Carrier film
Mold
Encapsulant
Flat surface
Exposed pads
12
Thermal cycling tests
-50C to +150C Testing of 50-component Daisy Chains
Conductive
epoxy
0 ohm surface
mount resistor
Silver traces and
pads
-50 C to 150 C
Microvia
Underfill
10 minute cycles
Chain resistance vs time
500 cycles/no failure
13
Using the modules
3D stand alone
assemblies
Miniature subsystems
connecting to PCB’s
or cables
Solder
connection
FR4 or Flex
Body orientation sensor
•
Accelerometer/magnetometer
Radio
•
Wireless transceiver
•
Modular construction
•
Mount on helmet
•
20mm x 25mm footprint
•
Powered by coin cell
Programming
cable (temporary)
MCU/Sensor
module
9-axis wireless
motion sensor
Miniature
Sensormodule
module
Sensor
wireless
sensors
Radio
Radio
Microcontroller
Microcontroller
BatteryBattery
Smart cable
Capital Equipment
Required
Paste fill & clean
station
Integrated Laser/PnP/Dispense
Encapsulation mold
18
Capital Equipment
NOT required
Resist exposure system
Etching/Plating tanks
Lamination
Press
Resist
stripper
19
Scaling to higher volume
Encapsulation mold
Epoxy
Dispenser
UV laser system
Pick and
Place
Paste fill & clean station
20
Summary
• Highly miniaturized circuits using nanosilver conductors
• Simplified design and fabrication
• Modular construction
• Quick/inexpensive prototyping
• Green processes
• Minimal capital equipment