temperature sensors on flexible substrates
DESCRIPTION
Temperature Sensors on Flexible Substrates. Z. Celik-Butler, D. Butler and M. Chitteboyina Nanotechnology Research and Teaching Facility University of Texas at Arlington http://www.uta.edu/engineering/nano/ March 13, 2009. Temperature Sensor - CoventorWare Model. Flexible superstrate. - PowerPoint PPT PresentationTRANSCRIPT
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Temperature Sensors on Flexible Temperature Sensors on Flexible SubstratesSubstrates
Z. Celik-Butler, D. Butler
and M. ChitteboyinaNanotechnology Research and Teaching Facility
University of Texas at Arlingtonhttp://www.uta.edu/engineering/nano/
March 13, 2009
2
Temperature Sensor - CoventorWare Model
Top surface is in contact with the
structure
Temperature sensor is connected to external flexible circuitry through the
flexible substrate
Temperature Sensor
Flexible superstrate
Flexible substrate
0.15cm x 0.05cm x 0.005 cm
cross-section cut
3
Temperature Sensor
Z-scale exaggerated 5 times
Aluminum
Flexible Substrate
Right arm of the temperature sensorLeft arm of the
temperature sensor
Sensor Element
Insulation Layers
4
Fabrication Process Flow for the Temperature Sensor
Clean silicon wafer
5
Fabrication Process Flow for the Temperature Sensor
100 nm silicon nitride layer
6
Fabrication Process Flow for the Temperature Sensor
Flexible Substrate
Polyimide ~ 40 µm
7
Fabrication Process Flow for the Temperature Sensor
Right electrode of the sensor
8
Fabrication Process Flow for the Temperature Sensor
Sensor Element
9
Fabrication Process Flow for the Temperature Sensor
First Insulation Layer
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Fabrication Process Flow for the Temperature Sensor
Left electrode of the sensor
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Fabrication Process Flow for the Temperature Sensor
Second Insulation Layer
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Fabrication Process Flow for the Temperature Sensor
Second Insulation Layer
Silicon Nitride ~ 100 nm
Flexible Superstrate
Polyimide ~ 40 µm
Undercut made to access the sensor
13
Fabrication Process Flow for the Temperature Sensor
Top aluminum surface will be in contact with the structure
Aluminum ~ 400 nm
14
Fabrication Process Flow for the Temperature Sensor
Sensor are connected to flexible circuitry through the
flexible substrate
Back side view of the Temperature Sensor
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Temperature Sensor Simulation Results
Bottom Flexible substrate kept either
floating or fixed at 300 K
Temperature Sensor CoventorWare Model
Simulated, heating thermal time constant = 0.07 ms
cooling thermal time constant = 0.67 ms
300
310
320
330
340
350
360
370
380
0 0.5 1 1.5 2 2.5 3
Thermal Transient Analysis of the Temperature Sensor
Te
mp
era
ture
(K
)
Time (ms)
Temperature pulse applied on the top aluminum surface
370.5 K
300.0 K
16April 28 2009
Temperature Sensor Fabrication
Right arm of the sensor Sensor Element First Insulation Layer
Left arm of the sensor Second Insulation Layer
STEP 1 STEP 2 STEP 3
STEP 4 STEP 5 Spin-coat and pattern polyimide superstrate layer
Deposit Aluminum layer
Etch the back-side of the wafer and get access to bond-pads
STEP 6, 7, 8
17July 21 2009
Temperature Sensor Fabrication
Spin-coat and pattern polyimide superstrate layer
Then deposited Aluminum on top of the superstrate layer to make contact with the structure
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Temperature Sensor Results
Resistance vs Temperature
3.2
3.25
3.3
3.35
3.4
3.45
3.5
3.55
3.6
25 35 45 55 65 75 85
Temperature (C)
Res
ista
nce
(MO
hms)
TS 80x80 µm Device 1 TS 80x80 µm Device 2
Resistance vs Temperature
3.3
3.4
3.5
3.6
3.7
3.8
20 30 40 50 60 70 80 90
Temperature (C)R
esis
tanc
e (M
Ohm
s)