Two-Layer Hall-Effect Model with Arbitrary Surface-Donor Profiles: Application to ZnO

Authors

David C. Look, Wright State University - Main CampusFollow

Document Type

Article

Publication Date

9-1-2008

Abstract

A complete two-layer Hall-effect model, allowing arbitrary donor and acceptor profiles, is presented and applied to the problem of conductive surface layers in ZnO. Temperature-dependent mobility and carrier concentration data in the temperature range of 20–320 K are fitted with an efficient algorithm easily implemented in commercial mathematics programs such as MATHCAD. The model is applied to two ZnO samples, grown by the melt (MLT) and hydrothermal (HYD) processes, respectively. Under the assumption of a “square” surface-donor profile, the fitted surface-layer thicknesses are 48 and 2.5 nm, respectively, for the MLT and HYD samples. The surface-donor concentrations are 7.6×10¹⁷ and 8.3×10¹⁸ cm⁻³, and the integrated surface-donor concentrations are 2.1×10¹² and 3.6×10¹² cm⁻². For an assumed Gaussian [N_Ds(0)exp(−z²/ds2)] donor profile, the fitted values of d_s are nearly the same as those for the square profile. The values of N_D,s(0) are about 50% larger and the integrated donor-concentration values are about 15% larger, for both samples. As a surface-analysis tool, the Hall effect is extremely sensitive and applicable over a wide range of surface-layer conditions.

Comments

Copyright © 2008, American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in the Journal of Applied Physics 104.6, and may be found at http://jap.aip.org/resource/1/japiau/v104/i6/p063718_s1

Repository Citation

Look, D. C. (2008). Two-Layer Hall-Effect Model with Arbitrary Surface-Donor Profiles: Application to ZnO. Journal of Applied Physics, 104 (6), 63718.
https://corescholar.libraries.wright.edu/physics/161

DOI

10.1063/1.2986143