Investigation of the optimal annealing temperature for the enhanced thermoelectric properties of MOCVD-grown ZnO films


Citar

Texto integral

Acesso aberto Acesso aberto
Acesso é fechado Acesso está concedido
Acesso é fechado Somente assinantes

Resumo

In this study, we demonstrate the optimization of the annealing temperature for enhanced thermoelectric properties of ZnO. Thin films of ZnO are grown on a sapphire substrate using the metal organic chemical Vapor Deposition (MOCVD) technique. The grown films are annealed in an oxygen environment at 600–1000°C, with a step of 100°C for one hour. Seebeck measurements at room temperature revealed that the Seebeck coefficient of the sample that was not annealed was 152 μV/K, having a carrier concentration of ND ~ 1.46 × 1018 cm–3. The Seebeck coefficient of the annealed films increased from 212 to 415 μV/K up to 900°C and then decreased at 1000°C. The power factor is calculated and found to have an increasing trend with the annealing temperature. This observation is explained by the theory of Johnson and Lark–Horovitz that thermoelectric properties are enhanced by improving the structure of ZnO thin films. The Hall measurements and PL data strongly justify the proposed argument.

Sobre autores

K. Mahmood

Department of Physics

Autor responsável pela correspondência
Email: khalid_mahmood856@yahoo.com
Paquistão, Faisalabad

A. Ali

Department of Physics

Email: khalid_mahmood856@yahoo.com
Paquistão, Faisalabad

M. Arshad

Department of Physics

Email: khalid_mahmood856@yahoo.com
Paquistão, Faisalabad

M. Ajaz un Nabi

Department of Physics

Email: khalid_mahmood856@yahoo.com
Paquistão, Faisalabad

N. Amin

Department of Physics

Email: khalid_mahmood856@yahoo.com
Paquistão, Faisalabad

S. Faraz Murtaza

Department of Physics

Email: khalid_mahmood856@yahoo.com
Paquistão, Faisalabad

S. Rabia

Department of Physics

Email: khalid_mahmood856@yahoo.com
Paquistão, Bahawalpur

M. Azhar Khan

Department of Physics

Email: khalid_mahmood856@yahoo.com
Paquistão, Bahawalpur

Arquivos suplementares

Arquivos suplementares
Ação
1. JATS XML

Declaração de direitos autorais © Pleiades Publishing, Inc., 2017