Electron effective mass in In0.33Ga0.67N determined by mid- infrared optical Hall effect

Authors

Nerijus Armakavicius, Linkoping University
Vallery Stanishev, Linkoping University
Sean Knight, University of Nebraska-Lincoln
Mathias Schubert, Linkoping University & University of Nebraska-Lincoln & Leibniz Institute for Polymer ResearchFollow
Vanya Darakchieva, Linkoping University

Date of this Version

2-20-2018

Citation

082103-2 Armakavicius et al. Appl. Phys. Lett. 112, 082103 (2018) Pages 1-5

Comments

Copyright APPLIED PHYSICS LETTERS 112, 082103 (2018)

Abstract

Mid-infrared optical Hall effect measurements are used to determine the free charge carrier parameters of an unintentionally doped wurtzite-structure c-plane oriented In_0.33Ga_0.67N epitaxial layer. Room temperature electron effective mass parameters of m_ ¼ ð0:20560:013Þm0 andm_k ¼ ð0:20460:016Þm0 for polarization perpendicular and parallel to the c-axis, respectively,were determined. The free electron concentration was obtained as (1.760.2)_1019 cm^-3. Within our uncertainty limits, we detect no anisotropy for the electron effective mass parameter and we estimate the upper limit of the possible effective mass anisotropy as 7%. We discuss the influence of conduction band nonparabolicity on the electron effective mass parameter as a function of In content. The effective mass parameter is consistent with a linear interpolation scheme between the conduction band mass parameters in GaN and InN when the strong nonparabolicity in InN is included. The In_0.33Ga_0.67N electron mobility parameter was found to be anisotropic, supporting previous experimental findings for wurtzite-structure GaN, InN, and AlxGa1_xN epitaxial layers with c-plane growth orientation.