All methods I found measured the frequency dependent dielectric but I'm looking for the DC dielectric conatant. And also I can't make a parallel plate capacitor from the thin film since it is conductive (so it won't be a capacitor). So how can I measure the dielectric constant of, for example, conductive polymer?
Thanks
Dear Dor Gotleyb,
The real part of permittivity (dielectric constant) of a conducting
or semiconducting material can not be measured at DC.
The minimum frequency where dielectric constant can be measured depends on conductivity. E.g. for semiconductors having resistivity
larger than 10 Ohm*cm it can be measured at microwave frequencies.
For metals dielectric constant is measurable at optical frequencies.
For noble metals it is negative in this frequency range.
On the other hand what is physical reason that you want to know dielectric constant for conducting materials at DC ?
With best regards
Jerzy Krupka
epsilon=epsilonR-i*sigma/omega, where epsilon is the complex permittivity, epsilonR is the real part of permittivity, sigma is conductivity and omega is frequency. So for a conductor with finite conductivity (sigma), at zero frequency (omega), i.e. DC case, epsilon has an infinite imaginary part. See https://en.wikipedia.org/wiki/Permittivity
Jerzy Antoni Krupka , when attaching two materials (lets suppose two semiconductors) there is a discontinuity in the electric field ( ε1*E1=ε2*E2 ) at the interface. I need the values of epsilons to do DC calculations.
To be honest, I'm quite confused of the various notations of epsilons (such as ε∞,εr,ε0,ε',ε'',εtotal) and which epsilon is presented in the electric field discontinuity boundary condition written above (is it just the real part of the permittivity?).
Thank you very much.
Thank you Jinsong Xu
So is there any meaning for this infinite imaginary part at DC?
I'm interested in the epsilon which found in the boundary condition between to materials: epsilon_1*E_1=epsilon_2*E_2.
I'm a bit confused of which epsilon is it?
Does it refer to epsilonR or to the total epsilon (epsilon=epsilonR-i*sigma/omega ), or maybe is it something else entirely?
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