Transcript Cryogenic Testing System

Dr. Vikram Kapoor
Dr. Kalpathy Sundaram
Group 2
Jomah Fangonilo
Shawn Hughes
Shawn Sickel
Antony Stabile
Jomah Fangonilo
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Specifically – to add additional testing
capabilities to the existing lab setup
◦ Current setup only allows for tests under room
temperature
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In general – many applications exist in the
fields of environmental testing, performance
improvement, failure analysis
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To implement a user-friendly high temperature test system
similar to the existing room temperature system.
Main Requirements
◦ Capable of testing devices up to 250° C
◦ Accuracy of ±1.5° C
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Derived Requirements
◦ Powered by 120 VAC 50/60 Hz
◦ Controller output ≤ 5A
◦ Surface measurements ≤ 1.5” x 1.5”
User
Thermometer
Controller
Heater
Power Supply
Probe Station
Data Acquisition
System
Outside Inside
Diameter Diameter Thickness Volts
3"
0.875"
0.25"
120
1.5” x 1.5”)
Watts
300
Watts per
Sq. In.
18
Approx.
Net Wt.
0.3 lb
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100-240 VAC
5A load max
3-wire Pt100 RTD or
Thermocouple
PID control
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Ramp/Soak
Free software
RS485
28,400 baud max
Cost efficient
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DB9 female connector for
RS232 to two wire
Terminal Block for RS485
Auto switching baud rate,
speed up to 115,200 baud
over a distance of 3,900
ft.
Two wire, different
signals, half duplex
Passive operation
Units connected together
in RS-485 multidrop
operation RoHS compliant.
$30.80
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100 Ohm Thin Film DIN
Platinum Class “B” (±0.12
Ohms, ±0.30°C at 0°C)
Accuracy Standard
◦ ±1.5° C at 250°
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Silicone Adhesive rated to
260°C (500°F)
Temperature Range; -73C to
260°C Continuous, 290°C
(554°F) Short Term Operation
When Installed with
OMEGABOND Air Set Cements
Sold in Convenient 3-Packs
($95)
Relatively low cost compared to
other RTD and thermocouple
options
High Temperature Test Results
300 µA
25° C
50° C
100° C
200 µA
200° C
100 µA
0 µA
0V
1V
2V
3V
4V
5V
150° C
Chromalox A-10 Disc Heater
$0
CN7533 Controller
$97
CN7533 Controller Software
$0
Speco RS232 to RS485 Converter
$30.80
Omega SA1-RTD-B (3-pack)
$95
Male-Male BNC Connectors
$9.55
Miscellaeous (Wires, terminals, etc)
$10
Total
$242
Sean Hughes
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Two different theories of when this temperature
reached.
Most scientists agree that when scale
refrigeration ends, cryogenic temperatures begin,
which happen at -240 °F ( -150 °C or 123 K)
The National Institute of Standards and
Technology at Boulder, Colorado have chosen
this point to occur at -180 °C (93.15 K) because
the boiling point of gases (such as He, H, O, N)
lie below 93 K and Freon refrigerants have a
boiling point above 93 K.
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Industries often tests devices at Extreme
Temperatures
◦ Largely due to environmental conditions
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Electronics operate at increased rates at low
temperatures
◦ MOSFETs
 Increased gain and speed at lower input voltages
 Less Current Leakage
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Semiconductors Characteristics Change at
Extreme Lows
◦ Freeze-Out – Silicon in the MOSFET begins to break
down and there will no longer be a connection between
the gate and the other components of the device and
can happen at 80K
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CTI-Model 22 Refrigerator with Janis
Research Co. Cold Head
CTI-Cryogenic 8001 Controller and 8300
Compressor
Polyscience 6706 Recirculating Chiller
GE Vacuum Pump
Temperature Controller
Cold Head – Houses
Semiconductor device, or
any other packaged device
being tested. Provides a
environment capable of
temperatures between
10K – 20K.
Device is wired to the platform via
copper probes to connect to
external testing equipment.
• 4145B Semicond. Parameter
Analyzer
• 4142A Impedance Analyzer
• 577 Curve Tracer
• The 8001 Controller basically acts as a power supply,
providing 208V/220V, 30A, 1-Phase to the 8300
Compressor and the Cold Head. NEMA: L6-15R
electrical supply.
• The 8300 Compressor provides 99.999% pure
compressed Helium
• Helium is mixed with oil to raise its specific heat
during compression
• Oil impurities are filtered from High pressure
helium
• Pure helium is delivered to the Cold Head, then
returns to the compressor
• During the process of compressing helium, heat is
generated which is removed by cooling water from
Chiller
• 2 gallon capacity cooling water (tap)
• Cooling water cycles through the 8300 Compressor,
dissipating excess heat
• Water into compressor: ~70°F
• Water out: ~80°F
• ~1.67kW of energy removed
• Accomplished by fans passing air over aluminum fins.
• 208/220V 20A, 1-phase NEMA:6-30P
• Tested resistivity at temperatures ranging from
~300K down to 60K, samples proved to have
poor thermal stability Temperature (K)
at low temperatures
300
Mega Ohms (MΩ)
3.906
200
15.944
130
26.971
117
30.010
100
40.721
60
119.557
<60
Error
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High Thermal Stability
◦ Maintained resistance when testing samples from
300K down to 20K
◦ Resistance ranged from 54.211Ω at 300K to
57.747 Ω at 20K
• 2N7000 is an N-Channel enhancement mode FET
Testing at low temperatures show an improvement in
performance.
• Vgs stepped from 3V to 10V
Room Temperature 300K
Low Temperature 80K
• Increase in Drain Current with the same Gate Voltage applied,
leading to an increase in transconductance from 300K (pictured
left) to 50K (pictured right)
Room Temperature 300K
Low Temperature 50K
Shawn Sickel
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Goals:
◦ Complete interface to Data Acquisition System
◦ Export the data in a compatible format for further
analysis in Advanced Design Systems (ADS)
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Specification:
◦ Read High Frequency Response within the
range of 130 MHz to 18 GHz
HP 8720B Vector Network Analyzer
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20+ years old
RF range of 130 MHz to 20 GHz
Incident power level from -10 to -65 dBm
Dynamic range of 85 dB
Needs to be calibrated before each use
Power Splitter / Combiner
High Pass Filter
Microwave Transistor
Amplifier
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Definition: The characteristics of the electrical
behavior of a device or change in medium
𝑆11 𝑆12
𝑆=
𝑆21 𝑆22
Used to find the relationship between
incident and reflected power waves, and the
distribution or splitting of power
Important for device operation
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Logarithmic Magnitude
Phase
Time Delay
Smith Chart
Polar
Linear Magnitude
Real
SWR
Hardware: Agilent GPIB/USB Interface
Software: Agilent I/O Suite 15.0
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Developed from scratch in visual basic
Used to operate the instrument as well as
gather data
From Device
Datasheet:
1 GHz -6.03
dB
2 GHz -5.95
dB
3 GHz -6.12
From
Acquired
dB
Data:
1 GHz -6.104
dB
2 GHz -6.311
dB
3 GHz -6.406
dB
ADS
Analysis
Using
exported .s2p
file
Datasheet
Data from
UCF RF &
Antennas Lab:
S21
1 GHz 17.125
dB
From
Acquired
Data:
S21
1 GHz 17.172
dB
UCF’s High Frequency Testing labs require
approval and Graduate Student Assistant
accompaniment
Antony Stabile
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Must be portably powered
Assembled on a printed circuit board
Must contain a load indicator
Stable switchable interface
Minimal Cost
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Must switch between at least four loads
50 ohm matched impedance
Cut-off frequency greater than 2 GHz
Coaxial connection to connect to spectrum
analyzer
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CMOS switches
◦ High attenuation about ~300 MHz
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Inductive Relay
◦ High power draw
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MEMS Relay
◦ Newest technology, high cost
Decision – Omron G6Z MEMS relay
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Need for stability
◦ Switch must be debounced
◦ RC circuit
 Low quality
◦ RC circuit with a Schmitt trigger
 Mid-range quality
◦ Integrated Circuit Solution
 Highest quality, high cost
Decision – RC circuit with Schmitt trigger
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Modulo 4 counter
Designed with CMOS logic
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LED indicators
◦ Simplest design
◦ Show physical location of active load
◦ Requires a demux/decoder
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Seven Segment Display
◦ Shows load number, which may be referenced
◦ Designed from CMOS logic
Decision – In order to minimize the size of the board,
only the seven segment display will be implemented.
Input select lines
come from state
transition circuit.
Output lines go to
inputs of a seven
segment display.
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Logic Gates and Relays require 5V supply
Power Supply must be stable, since the voltage
applied affects relay attenuation.
LM2575 Voltage regulator
◦ Requires input voltage greater than 7.5V
◦ Provides steady output of 5V
Decision – LM2575 Voltage regulator with 9V battery
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Microstrips are printed directly onto the
board.
Used to transmit between various
relays/coaxial connectors
Board must have a high dielectric strength to
avoid signal attenuation.
◦ FR-4
◦ Rogers RO4003
Decision – PCB with FR-4 Dielectric
Item
Unit Price
Quantity
Cost
G6Z-1PE High-Frequency Relay
$6.15
6
$36.90
LM2575 5V Voltage Regulator
$3.26
1
$3.26
4584 Hex Schmitt Trigger
4070 Quad XOR Gate
4071 Quad 2-input OR gate
$0.71
$0.77
$0.51
1
1
1
$0.71
$0.77
$0.51
4081 Quad 2-input AND gate
4013 Dual D-type flip-flop
Inductor, 330 uH
$0.50
$0.51
$1.33
1
1
1
$0.50
$0.51
$1.33
1N5819 Shottky Barrier Rectifier
$0.54
1
$0.54
SMA Female Coaxial Connectors
Seven-Segment Display
PCB Pushbutton Switch
Printed Circuit Board
Total Cost:
$3.19
$3.24
$1.36
$33.00
10
1
1
1
$31.90
$3.24
$1.36
$33.00
$114.53