High-Temperature Hardness of Bulk Single-Crystal AlN

Abstract

The hardness of single-crystal aluminum nitride (AlN) 0.5-mm-thick wafers was measured at elevated temperatures and compared with that of other semiconductors. A Vickers indentation method was used to determine the hardness under an applied load of 0.5–5 N in the temperature range 20–1400°C. The average hardness was measured as 17.7 GPa at room temperature. AlN exhibits a hardness higher than that of GaN in the entire temperature range investigated. A high mechanical stability for AlN at high temperatures is deduced.