I am trying to measure the capacitance of a small component over temperature, from about -40 to about 120 C. I have tested the bare fixture, and its capacitance seems to change by about 5% over this temperature range. As an example the fixturing changes from about 220 to about 200 fF (decreases as temp increases)
I think that this change might be from the plastic pieces of the fixture (PCB boards, cable insulation) changing dielectric constant over temperature. I looked for dielectric constant over temperature data for polymers but have not hae much luck.
Can anyone recommend a source (pref on the web) with data for dielectric constant over temperature for some polymers? Does anyone have a source for a discussion of this effect?
Thanks in advance,
Andrew