Liquid‐Phase Sintering of Aluminum Nitride by Europium Oxide Additives

Abstract

Europium oxide has been investigated as a sintering aid and dopant for AIN. Pressureless sintering was carried out with 0 to 9 wt% Eu 2 O 3 additives, and dense sintered specimens were obtained using 1 to 4 wt% Eu 2 O 3 . With increasing Eu 2 O 3 content, two additional phases were observed in the X‐ray diffraction patterns. The lattice parameters a and c of AIN in the wurtzite structure changed slightly and non‐monotonically with Eu 2 O 3 content and showed their minimum value in a 4 wt% Eu 2 O 3 sample. The Raman and photoluminescence spectra of sintered specimens were measured. These experimental results and the sintering mechanism in the system were discussed from the standpoint of the effects of oxygen, europium, and stress.