Influence of Annealing Condition on Exchange Bias of IrMn/GaMnAs Heterostructures

Hung-Ta Lin ,  Shuo-Hong Wang ,  Jin-Hua Huang ,  Tsung-Shune Chin 

Department of Materials Science and Engineering, National Tsing Hua University (NTHU), 101, Sec 2, Kuang-Fu Road, Hsinchu 30013, Taiwan


The exchange biasing properties of MnO/GaMnAs have been investigated by Eid et al. in detail by varying annealing condition. Moreover, a promising antiferromagnetic material IrMn has been identified due to its high exchange bias energy (Jk), high blocking temperature (Tb), and low critical thickness (~70 Å). The present work is a comparative study of exchange biasing of GaMnAs/IrMn heterostructures. Ga0.95Mn0.05As (30 nm) epilayers were grown by MBE system on semi-insulator GaAs (001) substrates. Then, the samples were transferred to another ultra high vacuum chamber to deposit the overgrown layers IrMn (10 nm)/Ta (5 nm) by dc magnetron sputtering system. In order to set up good exchange bias and decrease structural defects, the samples were annealed at temperature range from 150 to 200oC in a 1300 Oe field for 30 minutes. For as-prepared sample the magnetization curves show symmetric with respect to zero field, indicating absence of exchange bias. Moreover, the exchange bias effect was enhanced and demonstrated for GaMnAs/IrMn heterostructures after anneal procedure. Furthermore, the sample shows atomically flat with a root mean square (rms) roughness ~0.3 nm by atomic force microscopy (AFM). In spite of these new works, the origin of exchange bias with thermal treatment is not yet fully understood. Auger electron spectroscopy (AES) and Secondary Ion Mass Spectrometer (SIMS) analysis were carried out in order to study the extent of GaMnAs/IrMn interdiffusion during the thermal treatment. Furthermore, more magnetic characterization and detailed microstructures were performed and discussed by SQUID magnetometer and HRTEM analysis, respectively.

Legal notice
  • Legal notice:

    Copyright (c) Pielaszek Research, all rights reserved.
    The above materials, including auxiliary resources, are subject to Publisher's copyright and the Author(s) intellectual rights. Without limiting Author(s) rights under respective Copyright Transfer Agreement, no part of the above documents may be reproduced without the express written permission of Pielaszek Research, the Publisher. Express permission from the Author(s) is required to use the above materials for academic purposes, such as lectures or scientific presentations.
    In every case, proper references including Author(s) name(s) and URL of this webpage: must be provided.


Related papers
  1. A novel light high-entropy alloy Al20Be20Fe10Si15Ti35
  2. Photo-luminescent hydroxyapatite coatings through a bio-mimetic process
  3. Anomalous Hall effect in Mn-implanted p-type Si
  4. Preparation of gradually componential metal electrode on solution-casted NafionTM membrane

Presentation: Poster at E-MRS Fall Meeting 2006, Symposium E, by Hung-Ta Lin
See On-line Journal of E-MRS Fall Meeting 2006

Submitted: 2006-05-10 14:19
Revised:   2009-06-07 00:44
© 1998-2022 pielaszek research, all rights reserved Powered by the Conference Engine