Download Radiant Overview - Radiant Technologies, Inc.

Radiant Technologies, Inc.
Ferroelectric Test & Technology
Joe T. Evans, Jr.
August 22, 2016
Autonomous Memory
Radiant Technologies, Inc.
Radiant Technologies
• Focus on non-linear electromechanical materials
technology. The company
• Designs and manufactures test instruments and their
operating procedures
• Fabricates thin ferroelectric film devices
• Integrates the two disciplines to create unique
functions.
Autonomous Memory
Radiant Technologies, Inc.
Test Instruments
Radiant pioneered
ferroelectric test with
the development of the
first commercial test
system in 1989 and now
makes a variety of
testers and fixtures.
Autonomous Memory
Radiant Technologies, Inc.
Test Instrument vs Integrated
Ferroelectrics
What follows is a series of measurements demonstrating the
properties of Radiant’s thin PZT capacitors measured with
Radiant test equipment.
Autonomous Memory
Radiant Technologies, Inc.
IC Scale Cryogenic Testing
Lakeshore CRM-EM-HF
Autonomous Memory
Radiant Technologies, Inc.
IC Scale Cryogenic Testing
Hysteresis & Remanent @ 20V
[ AB403 ]
50
40
30
uC/cm2
20
10
0
-10
-20
-30
-40
-50
-20
-15
-10
-5
0
Voltage
5
10
15
20
0.25m-thick PZT from 10 K to 310 K
Autonomous Memory
Radiant Technologies, Inc.
Quantum Design PPMS P450
The QD Model P450 Multifunction Probe can test disc-shaped bulk
capacitors at high voltage down to 2.4 K.
B
Autonomous Memory
Radiant Technologies, Inc.
Bulk Capacitors vs Temperature
Many surprises await at lower temperatures.
Hyster esis at 300K, 253K, & 100K
[ CTS 3241 HD ]
Autonomous Memory
253K 700V 10s: Polarization (µC/cm2)
100 K 950V 1s: Polarization (µC/cm2)
300 K 580V 10s: Polarization (µC/cm2)
30
20
10
uC/cm2
The sample to the
right is a commercial
piezoelectric PZT
from CTS Wireless in
Albuquerque
measured in a PPMS
that indicates a
normal hysteresis
loop at room
temperature but
unexpectedly has no
remanent polarization
at 100 K.
0
-10
-20
-30
-1000
-800
-600
-400
-200
0
Voltage
200
400
600
800
Radiant Technologies, Inc.
1000
Leakage vs CV vs Remanent
Polarization
Decomposing the hysteresis loop on a probe
station.
Hysteresis Parameters
uC/cm^2, uA/cm^2, uF/cm^2
50
40
30
20
10
Rhyst
0
-6
-4
-2
-10
0
2
4
6
SW CV*10
nSW CV*10
-20
SW IV*2.5
-30
nSW IV*2.5
-40
Volts
Autonomous Memory
Radiant Technologies, Inc.
High Voltage Polarization &
Piezeoelectric Loops
Radiant Piezoelectr ic Refer ence Sample
[ PZT 12.75mm Dia - 1mm Thick ]
Proc. Hyst
Proc. Disp
Polarization (µC/cm2)
30
20
10
0
-10
-20
Displacement (Microns)
-30
0.5
0
-0.5
-1.0
-1200
-1000
-800
-600
Autonomous Memory
-400
-200
0
Volts
200
400
600
800
1000
Bulk Capacitor
displacement at
high voltage
and elevated
temperature.
Radiant Technologies, Inc.
Thin Film Polarization &
Piezeoelectric Loops
The laser vibrometer
can measure the
piezoelectric motion
of a thin ferroelectric
film capacitor
Autonomous Memory
Radiant Technologies, Inc.
Thin Solid Capacitor Piezo Loop
AFM Reference
[ Cap A ]
Proc. Hyst
Proc. Disp
25
Polarization (µC/cm2)
AFMs work too. Surface
piston of the 1µm-thick
PNZT at 25 volts and 500
hertz using an AFM. The
capacitor is clamped by the
substrate.
0
-25
15
Angstroms
10
5
0
-5
-25
Autonomous Memory
-20
-15
-10
-5
0
Volts
5
10
15
20
25
Radiant Technologies, Inc.
Thin Film PZT on Cantilever
Displacement vs Volts
0.5 um 52/48 PZT on 75mmx5mm Cantilever
10
Capturing e31 for
a thin film on a
cantilever surface
is a 3rd technique.
9
8
7
Microns
6
5
4
3
2
1
0
-1
-8
-6
Autonomous Memory
-4
-2
0
Period (ms)
2
4
6
8
Radiant Technologies, Inc.
Ferroelectric Transistor Operation
Switching vs Nonswitching IV
[ ND1-0903-2 ]
0.0000050
0.0000045
0.0000040
0.0000035
current
0.0000030
0.0000025
0.0000020
0.0000015
0.0000010
0.0000005
Source & Drain
0
-6
-4
-2
0
Volts
InOx
2
4
6
I2C DAC
Module
I2C Port
Premier II
d
g
Drive
Return
PZT
Gate
Autonomous Memory
Sensor
Radiant Technologies, Inc.
s
Radiant Technologies
• Integrated thin-ferroelectric-film capacitors.
 Radiant has developed a
manufacturable process
for discrete ferroelectric
capacitors.
 Radiant inserts packaged
capacitors into its testers
as test references.
 Radiant processes thin
PZT film wafers and
devices for researchers
studying non-linear
materials.
Autonomous Memory
Radiant Technologies, Inc.
Membrane Capacitors
• A three micron membrane with an embedded 1mthick PNZT capacitor.
Autonomous Memory
Radiant Technologies, Inc.
Membrane Capacitors
• Remanent strain movie if the same capacitor.
Autonomous Memory
Radiant Technologies, Inc.
pMEMs Devices
.
Autonomous Memory
We have work still to
do to reliably generate
reproducible devices.
Radiant Technologies, Inc.
Mechanically Coupled Capacitors
DRIVE
Actuator
Actuator
Sensor
RETURN
1.2mm
Sensor
Actuator
GND
Autonomous Memory
Radiant Technologies, Inc.
1
2
mm
White Light
Membrane
Numarski
A 1-square-millimeter capacitor with the majority of its
surface as a membrane. In white light the membrane looks
smooth but in Numarski the membrane is unmistakable.
Autonomous Memory
Radiant Technologies, Inc.
2
16mm
Membrane
A 16 square millimeter membrane soldered directly to a PCB
with an on-board charge amplifier that connects to the
Radiant EDU educational tester using telephone cable.
Pyroelectric constant is -22nC/cm2/K.
The membrane is too fragile to be
touched by a human.
Autonomous Memory
Radiant Technologies, Inc.
Autonomous Analog Switch
This entire PCB with discrete components and a packaged
ferroelectric capacitor can be shrunk into the same solid state
switch package on the PCB in the left image. This circuit can
stand-alone and resist disturbs from dramatic power-line
voltage events.
Autonomous Memory
Radiant Technologies, Inc.
Nuts & Volts
Magazine
“A Simple Ferroelectric
Memory”
February 2015 Issue
Autonomous Memory
Radiant Technologies, Inc.
Ferroelectric Circuits
Autonomous Event Detector
Autonomous
Memory
Event Input Line
Output Buffer
Ferroelectric
Capacitor
Input Overvoltage
Protection
Autonomous Memory
Radiant Technologies, Inc.
Demo Board - Piezo
Piezo Flapper
Latch
Event
Detector
This piezoelectric flapper is
a Measurement Specialties,
Inc. LDT0-28K Piezo Film
Sensor. Bent 90 degrees, it
generates exactly 7nC of
charge,
precisely
the
amount required to saturate
one of Radiant’s Type AB
20/80 PZT or Type AD
3/20/80 PNZT thin film
capacitors.
The Radiant ferroelectric
capacitor is encased in the
TO-18 transistor package
on the Event Detector
board.
Autonomous Memory
Radiant Technologies, Inc.
Magnetoelectric Sensor
Deposit magnetically sensitive material on membranes to
make magnetic field sensors. Below are dice from a wafer
prepared for this experiment but which have not yet seen the
backside DRIE. This project, executed in a CRADA with
SPAWAR, is difficult!
Autonomous Memory
Radiant Technologies, Inc.
Best Magnetoelectric Response
(so far)
Compare CapB Viring/+Pole/-Pole @ 50G
[ 1mm2 type AC w/nickel membrane ]
Cap B 180d -Pole: Sie-Trace Loop Avg. Filter: 1
Cap B 180d +Pole: Sie-Trace Loop Avg. Filter: 1
0.8
Cap B 180d Virgin: Se-Trace Loop Avg. Filter: 1
0.6
0.4
pC
0.2
0
-0.2
-0.4
-0.6
-50
-40
Autonomous Memory
-30
-20
-10
0
Oersted
10
20
30
40
50
Radiant Technologies, Inc.
Autonomous Event Detector Set
by a Magnetic Field?
Can we magnetomechanically switch
the ferroelectric capacitor and control
the switch?
Autonomous Memory
Radiant Technologies, Inc.