Low-frequency noise in polymer transistors

The low-frequency noise (LFN) properties of field-effect transistors (FETs) using polymers as the semiconducting substrate material are investigated and explained in terms of the nonstationary mobility mu in the semiconducting polymer. In the frequency (f) range f < 1 kHz it was found that 1/f noise prevails over other types of LFN in these polymer FETs (PFETs), The spectral density S-I of LFN of the drain current ID is proportional to the DC power V-DS II, applied to the PFETs channel, from the ohmic to the saturation modes of device operation. In addition, Sr is affected by the carrier mobility mu in PFETs channel, as mu in organic FETs is dependent on the biasing. Thus, S-I can have an additional sensitivity to I-D, that is, S-I proportional to (V-DS (.) I-D)(1-k), where k similar to 0.1, In general, the 1/f LFN of PFETs follows the relations that have been obtained for crystal and inorganic FETs with minor correction for nonstationary mobility mu.