Defect Characterization Using Raw Admittance Spectroscopy
journal contributionposted on 29.01.2021, 16:06 by Jian V. Li
We report a characterization technique that offers substantial improvement over the conventional practice of admittance spectroscopy, specifically in the processing of the admittance signal and the extraction of activation energy Ea and the attempt-to-escape frequency ν0, of the thermal activated process responsible for the admittance signal, most commonly being from electrically active defects in semiconductor materials. The extraction of these two parameters traditionally follows the procedure of conducting frequency or temperature differentiation of the raw admittance, identifying positions of the defect-signature peak, constructing an Arrhenius plot using the peak positions, and extracting Ea and ν0 by line fitting. We present a suite of Arrhenius transformations to transform and match the isorate and isothermal scans, carried out at a fixed point of the two-dimensional temperature–rate experimental space, onto one of the four virtual spaces: activation energy, the attempt-to-escape frequency, temperature, and rate. We match the Arrhenius-transformed scans to each other to extract Ea and ν0 using only the raw capacitance and conductance data without taking the frequency/temperature derivative or using the Arrhenius plot.