Non-Resonant Thermal Admittance Spectroscopy

TL;DR

This paper addresses the limitations of Thermal Admittance Spectroscopy in high trap density semiconductors by developing tools to detect and correct for Fermi-level pinning effects, improving trap state analysis accuracy.

Contribution

It introduces methods to identify and account for Fermi-level pinning in TAS, enhancing the reliability of trap state density measurements in semiconductors with high trap densities.

Findings

Developed detection techniques for Fermi-level pinning in TAS.

Provided correction methods to improve trap density estimation.

Enhanced understanding of TAS limitations at high trap densities.

Abstract

Thermal Admittance Spectroscopy (TAS) as become a popular technique to determine trap state density and energetic position in semiconductors. In the limit of a large number of trap states ($>10^{16} \text{cm}^{-3}$), Fermi-level pinning undermines the assumptions used in the analysis of TAS data, which leads to a significant underestimation of the trap state density. Here, we develop the tools to detect and account for the occurrence of Fermi-level pinning in TAS measurements.