Determining substrate temperature in an AC inverted cylindrical magnetron sputtering PVD system

The substrate temperature achieved during physical vapor deposition significantly affects the properties and phases of thin films. An Isoflux ICM-10 Dual Target Inverted Cylindrical Magnetron Sputtering system is used to deposit low temperature alpha-phase alumina, for which an experimentally determined substrate temperature is desired. Constraints inherent to the Isoflux system limit the use of a thermocouple. Instead, a pressure vessel containing numerous samples of temperature indicating liquids is placed in the chamber during operation. These indicator paints are observed upon completion of the deposition process to record the substrate temperature. Measurements indicate a temperature range of 343 °C to 399 °C for our alpha-phase alumina films deposited at a pressure of 0.27 Pa (2 mTorr), a substrate bias of − 35 V, and a power of 5 kW. Theoretical heat transfer calculations support the experimental measurements. A parametric investigation showed that the removal of the − 35 V substrate bias decreases the substrate temperatures by approximately 35 °C and that the substrate temperature increases about 50 °C for each additional kilowatt of power in the range of 1 kW to 6 kW.