1. Carbon wire sensor based in semiconductor strain gauges
CONCEPT
Sensor 5
Ceramic isolators Ø 1.2
Sleeve in copper
Soldering
Carbon Wire 5
Action to be
measured by
the sensor
Fork Arm
~ SCALE 10:1

2. Carbon wire sensor based in semiconductor strain gauges
Option
Description GF
Feasibility
Remarks
Cermet Resistor on alumina
Printed Cermet circuit on alumina.
Baking cycle 800 Celsius
Electrical leads and path for cable soldering metalized in the ceramic
~ 15
Technology is well known
Metal printed circuit on ceramic
Printed circuit on alumina.
~ 2
Technology is well known,
don’t know if this technology has been used for such sensors
ScSG Brazed on ceramic plate
Silicon cutting
Silicon ends metallization
Ceramic metallization
Brazing (in vacuum furnace)
~ 100 (expected)
Technologies are known don’t know if this technology has been use for sensors.
Production process complex.
Suitable strain gauge thickness ~ 200um
Silicon metallization can change gauge properties.
Brazing process could induce residual stress.
Silicon material
ScSG from SOI
SOI wafer etching
Electrical lead by metallization of bonding
Path for cable soldering metalized Silicon oxide layer
Technology is known
Examples of application for sensor can be found in the literature
SOI material type

3. Decide on sensor technology Final prototype design
Carbon wire sensor based in semiconductor strain gauges
Next steps:
Define final requirements i.e, suitable gauge factor, sensor dimensions
Fix conceptual design
Decide on sensor technology
Final prototype design
Prototype production
Test and characterization
Final design
Final production