Doug,
In my experience coming up with the resistivity of a copper foil can be
tricky and challenging.
I know you do your experiments very carefully, but the first obvious
challenge is that you also need interim parameters to get to the
resistivity.
For instance, you need the thickness and material density may vary
dependent on how the foil was created: electro-deposited or rolled
annealed. The sheet resistance formula also assumes conditions that
require special attention when measurements are done...
Regards,
Istvan Novak
Oracle
On 10/23/2015 2:00 AM, Doug Brooks wrote:
I am looking for some thoughts on some measurements I have just taken
I have a new test board I have done some preliminary measurements on,
and have come up with the following measurements:
Resistivity 0.8666 micro-ohm in (expected 0.67)
Thermal coefficient of resistivity (alpha) .0048 (expected .0038)
The "expected" values are the published values for "copper", not
processed copper on a PCB. Have any of you done similar measurements and
come up with similar values?
Doug