Abstract
The thermal conductivity of oxide thin films deposited using dc, rf, and ion-beam sputtering is measured in the temperature range 80–400 K using the 3ω method. Thermal conductivity data for amorphous thin films of are nearly identical to bulk a-. Data for amorphous , while having a magnitude and temperature dependence similar to bulk amorphous oxides, show a dependence on deposition method; rf sputtering of an target produces films with a thermal conductivity 35% smaller than films prepared by ion-beam sputtering. Microcrystalline thin films show a rich variety of behavior: the conductivity of films depends on the substrate tempreature and approaches the thermal conductivity of bulk ceramics when ≃400 °C; films show glasslike thermal conductivity independent of annealing temperature up to 900 °C; and MgO films display a crystalline thermal conductivity that is greatly reduced relative bulk values.
- Received 16 March 1995
DOI:https://doi.org/10.1103/PhysRevB.52.253
©1995 American Physical Society