In-situ annealing characterization of atomic-layer-deposited Al2O3 in N2 , H2 and vacuum atmospheres

Research output: Contribution to journalArticleScientificpeer-review

Researchers

Research units

  • Okmetic Oyj
  • University of Jyväskylä

Abstract

Atomic-layer-deposited Al 2 O 3 films can be used for passivation, protective, and functional purposes in electronic devices. However, as-deposited, amorphous alumina is susceptible to chemical attack and corrosion during manufacturing and field-use. On the contrary, crystalline Al 2 O 3 is resistant against aggressive chemical treatments and corrosion. Here, high-temperature treatments in N 2 , H 2 , and vacuum were used to crystallize alumina which exhibited different crystalline phases. The annealing process was monitored continuously in situ by measuring the film temperature and surface reflectance to understand the crystallization kinetics. Ex-situ x-ray diffraction, electron microscopy, and composition analysis were used to probe the structure of the crystallized films and explain the formation of different alumina phases. This study provides a set of boundary conditions, in terms of temperature and atmosphere, for crystallizing chemically stable atomic-layer-deposited alumina for applications requiring a film thickness in the range of tens of nanometers without defects such as cracks.

Details

Original languageEnglish
Pages (from-to)147-155
Number of pages9
JournalThin Solid Films
Volume682
Early online date1 Jan 2019
Publication statusE-pub ahead of print - 1 Jan 2019
MoE publication typeA1 Journal article-refereed

    Research areas

  • Aluminum oxide, Atomic layer deposition, Barrier film, Crystallization, High-temperature annealing

ID: 33975003