Effect of post-deposition annealing on composition and electrical properties of dc reactive magnetron sputtered Al2O3 thin films. (March 2014)

• Record Type: Journal Article
• Authors: Prasanna, S.; Shaik, H.; Mohan Rao, G.; Vandana; Singh, P. K.; Jayakumar, S.; Balasundaraprabhu, R.
• Is Part Of: Materials technology. Volume 29:Number 2(2014)
• Page Start: 83
• Page End: 89
• Publication Date: 2014-03
• Subjects: Materials -- Periodicals; Materials science -- Periodicals; Materials -- Technological innovations -- Periodicals; 620.1105
• DOI: 10.1179/1753555713Y.0000000108
• Languages: English
• ISSNs: 1066-7857

Abstract

<abstract> <title> <x content-type="archive" xml:space="preserve">Abstract</x> </title> <p>We have investigated the effect of post-deposition annealing on the composition and electrical properties of alumina (Al₂O₃) thin films. Al₂O₃ were deposited on n-type Si &lt;100&gt; substrates by dc reactive magnetron sputtering. The films were subjected to post-deposition annealing at 623, 823 and 1023 K in vacuum. X-ray photoelectron spectroscopy results revealed that the composition improved with post-deposition annealing, and the film annealed at 1023 K became stoichiometric with an O/Al atomic ratio of 1·49. Al/Al₂O₃/Si metal–oxide–semiconductor (MOS) structures were then fabricated, and a correlation between the dielectric constant ϵ_r and interface charge density <italic>Q</italic>_i with annealing conditions were studied. The dielectric constant of the Al₂O₃ thin films increased to 9·8 with post-deposition annealing matching the bulk value, whereas the oxide charge density decreased to 3·11×10¹¹ cm⁻². Studies on current–voltage <italic>IV</italic> characteristics indicated ohmic and Schottky type of conduction at lower electric fields (&lt;0·16 MV cm⁻¹) and space charge limited conduction at higher electric fields.</p> </abstract>