Insight of mechanical and morphological properties of ALD- Al2O3 films in point of structural properties


Nalçacı B., Polat Gönüllü M.

APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING, vol.127, no.6, 2021 (Peer-Reviewed Journal) identifier identifier

  • Publication Type: Article / Article
  • Volume: 127 Issue: 6
  • Publication Date: 2021
  • Doi Number: 10.1007/s00339-021-04601-x
  • Journal Name: APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
  • Journal Indexes: Science Citation Index Expanded, Scopus, Academic Search Premier, Aerospace Database, Chemical Abstracts Core, Chimica, Communication Abstracts, Compendex, INSPEC, Metadex
  • Keywords: Al2O3 thin films, ALD, Structural properties, Phase transformations, Nanoindentation, ALUMINA THIN-FILMS, CHEMICAL-VAPOR-DEPOSITION, ATOMIC LAYER DEPOSITION, ELECTRICAL INSULATION, OPTICAL-PROPERTIES, PHASE-TRANSITION, OXIDE, TEMPERATURE, COATINGS, BEHAVIOR

Abstract

Aluminum oxide (Al2O3) has revealed many applications in diverse areas from optoelectronic devices to passivation according to its some physical, chemical, and mechanical properties. So, this paper focuses on the effect of structural changes on film properties in the point of post-annealing temperatures. Films have been growth by atomic layer deposition technique at 200 degrees C on p-type Si substrates. Following that post-annealing process has been implemented in argon gas flow in the temperatures range from 700 to 1100 degrees C for 5 h. The variation of the crystallographic structure has been investigated by X-ray diffraction method. The microstructural alterations of alumina films have been displayed by scanning electron microscopy and elemental compositions have been obtained by energy-dispersive X-ray spectroscopy. Surface morphologies of the films have been determined by atomic force microscopy. Furthermore, mechanical properties have been investigated by nanoindentation. Results showed that post-annealing temperatures have critical influences on the formation and transformations of different phases (gamma, theta, alpha), interdiffusion between the Si substrate and Al2O3 thin films, mechanical properties, and surface roughness of Al2O3 thin films.