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

THIN SOLID FILMS

卷:682

Article

Broas, Mikael¹  Lemettinen, Joni²  Sajavaara, Timo³  Tilli, Markku⁴  Vuorinen, Vesa¹  Suihkonen, Sami²  Paulasto-Krockel, Mervi¹ 

[1] Aalto Univ, Dept Elect Engn & Automat, POB 13500, FIN-00076 Espoo, Finland

[2] Aalto Univ, Dept Elect & Nanoengn, POB 13500, FIN-00076 Espoo, Finland

[3] Univ Jyvaskyla, Dept Phys, POB 35, FIN-40014 Jyvaskyla, Finland

[4] Okmet Oy, Piitie 2, Vantaa 01510, Finland

关键词: Atomic layer deposition;    Aluminum oxide;    Barrier film;    High-temperature annealing;    Crystallization;   

DOI  :  10.1016/j.tsf.2019.03.010

来源: Elsevier

【 摘 要 】

Atomic-layer-deposited Al2O3 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 Al2O3 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.

【 授权许可】

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