Magnetic Domain Characterization and Physical Properties of Gd-Doped and (Gd, Al) Co-Doped ZnO Thin Films
Undoped ZnO, Gd-doped ZnO with various doping concentration (1, 3, 5, and 7 at%), and 3 at% (Gd, Al) co-doped ZnO films were prepared on a glass substrate using the co-reactive sputtering method. The influence of the doping and co-doping process on the films was characterized using X-ray diffraction...
Main Authors: | , , , , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
MDPI AG
2022-11-01
|
Series: | Materials |
Subjects: | |
Online Access: | https://www.mdpi.com/1996-1944/15/22/8025 |
_version_ | 1797464766831132672 |
---|---|
author | Nur Amaliyana Raship Siti Nooraya Mohd Tawil Nafarizal Nayan Khadijah Ismail Anis Suhaili Bakri Zulkifli Azman Faezahana Mohkhter |
author_facet | Nur Amaliyana Raship Siti Nooraya Mohd Tawil Nafarizal Nayan Khadijah Ismail Anis Suhaili Bakri Zulkifli Azman Faezahana Mohkhter |
author_sort | Nur Amaliyana Raship |
collection | DOAJ |
description | Undoped ZnO, Gd-doped ZnO with various doping concentration (1, 3, 5, and 7 at%), and 3 at% (Gd, Al) co-doped ZnO films were prepared on a glass substrate using the co-reactive sputtering method. The influence of the doping and co-doping process on the films was characterized using X-ray diffraction, FESEM, EDX, MFM, VSM, UV–VIS spectroscopy, and the Hall Effect measurement at room temperature. XRD study confirmed that the Gd and Al ions are incorporated into a ZnO lattice. EDX analysis confirmed the existence of Zn, O, Al, and Gd elements in the prepared Gd-doped ZnO and (Gd, Al) co-doped ZnO films, which suggests the successful doping procedure. All the deposited films obtained maximum optical transmittance above 80%, showing a high transparency of the films in the visible region. The optical band gap was found red-shifted from 3.11 to 3.21 eV with the increase in Gd doping concentration. The increase in band gap energy from 3.14 eV to 3.16 eV was obtained for 3 at% Gd and 3 at% (Gd, Al) co-doped ZnO films. The MFM measurement proved the existence of room-temperature ferromagnetism and spin polarization in Gd and (Gd, Al) co-doped ZnO films. By co-doping with Al, the result obtained from MFM shows the enhancement of magnetic properties, as it exhibited a smaller domain size with a shorter magnetic correlation length <i>L</i>, a larger phase shift Φ<sub>rms</sub>, and the highest value of <i>δf</i><sub>rms</sub> compared to the sample with 3 at% Gd incorporated into ZnO. The carrier concentration and electrical conductivity increased with the increase in Gd concentration, whereas the electrical resistivity and hall mobility showed a reverse trend. The similar trend of results obtained for 3 at% (Gd, Al) co-doped ZnO as compared to 3 at% Gd-doped ZnO also indicates greater electrical properties after a shallow donor such as aluminum was incorporated into Gd-doped ZnO thin films. In conclusion, for future applications, one should consider the possible influence of other types of shallow donor incorporation in an attempt to enhance the properties of new types of diluted magnetic semiconductors (DMSs). |
first_indexed | 2024-03-09T18:11:55Z |
format | Article |
id | doaj.art-8d489b8646ef4bf090a1af6dcec1f19e |
institution | Directory Open Access Journal |
issn | 1996-1944 |
language | English |
last_indexed | 2024-03-09T18:11:55Z |
publishDate | 2022-11-01 |
publisher | MDPI AG |
record_format | Article |
series | Materials |
spelling | doaj.art-8d489b8646ef4bf090a1af6dcec1f19e2023-11-24T09:02:56ZengMDPI AGMaterials1996-19442022-11-011522802510.3390/ma15228025Magnetic Domain Characterization and Physical Properties of Gd-Doped and (Gd, Al) Co-Doped ZnO Thin FilmsNur Amaliyana Raship0Siti Nooraya Mohd Tawil1Nafarizal Nayan2Khadijah Ismail3Anis Suhaili Bakri4Zulkifli Azman5Faezahana Mohkhter6Department of Electrical and Electronic Engineering, Universiti Pertahanan Nasional Malaysia (UPNM), Kem Sungai Besi, Kuala Lumpur 57000, MalaysiaDepartment of Electrical and Electronic Engineering, Universiti Pertahanan Nasional Malaysia (UPNM), Kem Sungai Besi, Kuala Lumpur 57000, MalaysiaMicroelectronic and Nanotechnology-Shamsuddin Research Centre (MiNT-SRC), Universiti Tun Hussein Onn Malaysia (UTHM), Parit Raja 86400, MalaysiaDepartment of Electrical and Electronic Engineering, Universiti Pertahanan Nasional Malaysia (UPNM), Kem Sungai Besi, Kuala Lumpur 57000, MalaysiaFaculty of Electrical and Electronic Engineering, Universiti Tun Hussein Onn Malaysia (UTHM), Parit Raja 86400, MalaysiaFaculty of Electrical and Electronic Engineering, Universiti Tun Hussein Onn Malaysia (UTHM), Parit Raja 86400, MalaysiaMicroelectronic and Nanotechnology-Shamsuddin Research Centre (MiNT-SRC), Universiti Tun Hussein Onn Malaysia (UTHM), Parit Raja 86400, MalaysiaUndoped ZnO, Gd-doped ZnO with various doping concentration (1, 3, 5, and 7 at%), and 3 at% (Gd, Al) co-doped ZnO films were prepared on a glass substrate using the co-reactive sputtering method. The influence of the doping and co-doping process on the films was characterized using X-ray diffraction, FESEM, EDX, MFM, VSM, UV–VIS spectroscopy, and the Hall Effect measurement at room temperature. XRD study confirmed that the Gd and Al ions are incorporated into a ZnO lattice. EDX analysis confirmed the existence of Zn, O, Al, and Gd elements in the prepared Gd-doped ZnO and (Gd, Al) co-doped ZnO films, which suggests the successful doping procedure. All the deposited films obtained maximum optical transmittance above 80%, showing a high transparency of the films in the visible region. The optical band gap was found red-shifted from 3.11 to 3.21 eV with the increase in Gd doping concentration. The increase in band gap energy from 3.14 eV to 3.16 eV was obtained for 3 at% Gd and 3 at% (Gd, Al) co-doped ZnO films. The MFM measurement proved the existence of room-temperature ferromagnetism and spin polarization in Gd and (Gd, Al) co-doped ZnO films. By co-doping with Al, the result obtained from MFM shows the enhancement of magnetic properties, as it exhibited a smaller domain size with a shorter magnetic correlation length <i>L</i>, a larger phase shift Φ<sub>rms</sub>, and the highest value of <i>δf</i><sub>rms</sub> compared to the sample with 3 at% Gd incorporated into ZnO. The carrier concentration and electrical conductivity increased with the increase in Gd concentration, whereas the electrical resistivity and hall mobility showed a reverse trend. The similar trend of results obtained for 3 at% (Gd, Al) co-doped ZnO as compared to 3 at% Gd-doped ZnO also indicates greater electrical properties after a shallow donor such as aluminum was incorporated into Gd-doped ZnO thin films. In conclusion, for future applications, one should consider the possible influence of other types of shallow donor incorporation in an attempt to enhance the properties of new types of diluted magnetic semiconductors (DMSs).https://www.mdpi.com/1996-1944/15/22/8025Gd-doped ZnOshallow donormagnetic force microscopyco-dopingsputtering |
spellingShingle | Nur Amaliyana Raship Siti Nooraya Mohd Tawil Nafarizal Nayan Khadijah Ismail Anis Suhaili Bakri Zulkifli Azman Faezahana Mohkhter Magnetic Domain Characterization and Physical Properties of Gd-Doped and (Gd, Al) Co-Doped ZnO Thin Films Materials Gd-doped ZnO shallow donor magnetic force microscopy co-doping sputtering |
title | Magnetic Domain Characterization and Physical Properties of Gd-Doped and (Gd, Al) Co-Doped ZnO Thin Films |
title_full | Magnetic Domain Characterization and Physical Properties of Gd-Doped and (Gd, Al) Co-Doped ZnO Thin Films |
title_fullStr | Magnetic Domain Characterization and Physical Properties of Gd-Doped and (Gd, Al) Co-Doped ZnO Thin Films |
title_full_unstemmed | Magnetic Domain Characterization and Physical Properties of Gd-Doped and (Gd, Al) Co-Doped ZnO Thin Films |
title_short | Magnetic Domain Characterization and Physical Properties of Gd-Doped and (Gd, Al) Co-Doped ZnO Thin Films |
title_sort | magnetic domain characterization and physical properties of gd doped and gd al co doped zno thin films |
topic | Gd-doped ZnO shallow donor magnetic force microscopy co-doping sputtering |
url | https://www.mdpi.com/1996-1944/15/22/8025 |
work_keys_str_mv | AT nuramaliyanaraship magneticdomaincharacterizationandphysicalpropertiesofgddopedandgdalcodopedznothinfilms AT sitinoorayamohdtawil magneticdomaincharacterizationandphysicalpropertiesofgddopedandgdalcodopedznothinfilms AT nafarizalnayan magneticdomaincharacterizationandphysicalpropertiesofgddopedandgdalcodopedznothinfilms AT khadijahismail magneticdomaincharacterizationandphysicalpropertiesofgddopedandgdalcodopedznothinfilms AT anissuhailibakri magneticdomaincharacterizationandphysicalpropertiesofgddopedandgdalcodopedznothinfilms AT zulkifliazman magneticdomaincharacterizationandphysicalpropertiesofgddopedandgdalcodopedznothinfilms AT faezahanamohkhter magneticdomaincharacterizationandphysicalpropertiesofgddopedandgdalcodopedznothinfilms |