Accession Number:

ADA561168

Title:

Growth, Structure, and Thermal Conductivity of Yttria-Stabilized Hafnia Thin Films (Postprint)

Descriptive Note:

Technical paper 5 Mar 2008-12 Jan 2012

Corporate Author:

AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH MATERIALS AND MANUFACTURING DIRECTORATE

Personal Author(s):

• Jones, John G.
• Ramana, C. V.
• Noor-A-Alam, M.
• Gengler, Jamie J.

Report Date:

2012-01-01

Pagination or Media Count:

8.0

Abstract:

Yttria-stabilized hafnia YSH films of 90 nm thickness have been produced using sputter-deposition by varying the growth temperature Ts from room-temperature RT to 400 deg C. The effect of Ts on the structure, morphology, and thermal conductivity of YSH films has been investigated. Structural studies indicate that YSH films crystallize in the cubic phase. The lattice constant decreases from 5.15 to 5.10 A with increasing Ts. The average grain size L increases with increasing TsL-Ts relationship indicates the thermally activated process of the crystallization of YSH films. The analyses indicate a critical temperature to promote nanocrystalline, cubic YSH films in 300 deg C, which is higher comparte to that of pure monoclinic HfO2 films. Compared to pure nanocrystalline hafnia, the addition of yttria lowers the effective thermal conductivity. The effect of grain size on thermal conductivity is also explored.

Descriptors:

• *REFRACTORY MATERIALS
• *THERMAL CONDUCTIVITY
• CHEMICAL PROPERTIES
• CHEMICAL STABILITY
• CRITICAL TEMPERATURE
• CRYSTAL LATTICES
• CRYSTALLIZATION
• GRAIN SIZE
• GROWTH(GENERAL)
• MORPHOLOGY
• PHYSICAL PROPERTIES
• REPRINTS
• ROOM TEMPERATURE
• STRUCTURAL PROPERTIES
• THICKNESS
• THIN FILMS
• TIME DOMAIN

Subject Categories:

• Ceramics, Refractories and Glass

Distribution Statement:

APPROVED FOR PUBLIC RELEASE