Extraction of Isotropic Electron-Nuclear Hyperfine Coupling Constants of Paramagnetic Point Defects from Near-Zero Field Magnetoresistance Spectra via Least Squares Fitting to Models Developed from the Stochastic Quantum Liouville Equation

TL;DR

This paper introduces a least squares fitting method based on the stochastic quantum Liouville equation to extract hyperfine coupling constants from near-zero field magnetoresistance spectra, aiding defect analysis in semiconductors.

Contribution

It presents a novel fitting approach that simplifies the extraction of hyperfine parameters from NZFMR spectra, applicable to various semiconductor defect systems.

Findings

Fitted hyperfine parameters agree with existing defect knowledge.

Method successfully applied to Si/SiO2 MOSFETs and a-Si:H MIS capacitors.

Demonstrates NZFMR as a powerful tool for defect characterization.

Abstract

We report on a method by which we can systematically extract spectroscopic information such as isotropic electron-nuclear hyperfine coupling constants from near-zero field magnetoresistance spectra. The method utilizes a least squares fitting of models developed from the stochastic quantum Liouville equation. We applied our fitting algorithm to two distinct material systems: Si/SiO2 MOSFETs, and a-Si:H MIS capacitors. Our fitted results and hyperfine parameters are in reasonable agreement with existing knowledge of the defects present in the systems. Our work indicates that the NZFMR response and fitting of the NZFMR spectrum via models developed from the stochastic quantum Liouville equation could be a relatively simple yet powerful addition to the family of spin-based techniques used to explore the chemical and structural nature of point defects in semiconductor devices and insulators.