AUTHOR=Khojaste khoo M. , Kameli P. 

TITLE=Structure and Magnetization of Strontium Hexaferrite (SrFe12O19) Films Prepared by Pulsed Laser Deposition

JOURNAL=Frontiers in Materials

VOLUME=8

YEAR=2021

URL=https://www.frontiersin.org/journals/materials/articles/10.3389/fmats.2021.717251

DOI=10.3389/fmats.2021.717251

ISSN=2296-8016

ABSTRACT=<p>M-type strontium hexaferrite (SrM) thin films show excellent magnetic properties and uniaxial magnetic anisotropy. We systematically investigated the magnetism of SrM films prepared by pulsed-laser deposition on different substrates [Al<sub>2</sub>O<sub>3</sub> (<inline-formula id="inf1"><mml:math id="m1" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mn>1</mml:mn><mml:mrow><mml:mover accent="true"><mml:mn>1</mml:mn><mml:mo>¯</mml:mo></mml:mover></mml:mrow><mml:mn>02</mml:mn></mml:mrow></mml:math></inline-formula>), SrTiO<sub>3</sub> (100), ZnO (0001), and LiNbO<sub>3</sub> (0001)] at vacuum (10<sup>−4</sup> Pa) and a substrate temperature of 800°C. Prepared films were annealed in air at a temperature of 1,000°C for 2 hours. This investigation determined the effect of annealing and different substrates on the morphology, strain, and hysteresis loops of the films. The prepared films were characterized using x-ray diffractometry, Raman spectroscopy, scanning electron microscopy, and superconducting quantum interference device (SQUID) magnetometry. X-ray diffraction analyses confirmed c-oriented growth along the out-of-plane direction in most films. We found that annealing causes enhanced crystallization in films and a significant increase in coercivity. The highest coercivity of ∼11 KOe was measured for the film deposited on the Al<sub>2</sub>O<sub>3</sub> (<inline-formula id="inf2"><mml:math id="m2" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mn>1</mml:mn><mml:mrow><mml:mover accent="true"><mml:mn>1</mml:mn><mml:mo>¯</mml:mo></mml:mover></mml:mrow><mml:mn>02</mml:mn></mml:mrow></mml:math></inline-formula>) substrate.</p>