Open AccessCharacterization of Zn coated Radio Frequency sputtered AZO thin films
Author(s) -
Tushar K. Ghosh
Publication year - 2019
Publication title -
international journal of innovative research in physics
Language(s) - English
Resource type - Journals
eISSN - 2689-484X
pISSN - 2687-7902
DOI - 10.15864/ijiip.1101
Subject(s) - materials science , indium tin oxide , doping , optoelectronics , sputtering , thin film , electrical resistivity and conductivity , indium , transparent conducting film , sputter deposition , oxide , nanotechnology , metallurgy , electrical engineering , engineering
Transparent conducting oxides (TCOs) have become an essential part of today’s life through their application in touch screen technology. The growing interest for superior and cheap transparent conducting films, primarily driven by the smart televisions and phones market, has led to renewed efforts to develop novel TCOs. Currently, the most widely used material for transparent conducting applications is Sn-doped indium oxide (ITO), but this material is expensive. Al-Doped zinc oxide (AZO) is among the few metal oxides which can replace costly tin doped indium oxide (ITO) due to many properties similar to it. Thin films of AZO of different thickness 100 nm, 200 nm, 300 nm were deposited on glass substrates using Al doped ZnO target by RF magnetron sputtering system and 15 nm Zn layer on top of it by DC magnetron sputtering system and annealed in inert environment. These films show a carrier concentration of 2.28× 10 21 cm -3, mobility of 27 cm 2 /V-s and resistivity of 10 -4 Ω-cm. Such a low value of resistivity is attributed to a dense compact columnar morphology of the sputtered films as evident from FESEM micrograph. The nanocolumns of such close proximity with higher surface related defects increase the carrier concentration enormously. As a result, compact columnar structure improves conduction process and increases electrical conductivity which is comparable to the standard TCO characteristics used in the optoelectronic devices.