Sharp bound and free exciton lines from homoepitaxial AlN

✍ Scribed by Feneberg, Martin ;Neuschl, Benjamin ;Thonke, Klaus ;Collazo, Ramón ;Rice, Anthony ;Sitar, Zlatko ;Dalmau, Rafael ;Xie, Jinqiao ;Mita, Seiji ;Goldhahn, Rüdiger

• Book ID: 105366038
• Publisher: John Wiley and Sons
• Year: 2011
• Tongue: English
• Weight: 177 KB
• Volume: 208
• Category: Article
• ISSN: 0031-8965
• DOI: 10.1002/pssa.201000947

✦ Synopsis

Abstract

MOCVD AlN layers grown in c‐direction on PVT bulk AlN substrates are investigated by high‐resolution photoluminescence in the energy region of the band gap. The experiments allow for observation of different donor bound exciton lines with a full width at half maximum below 0.5 meV. Assignments are suggested for the substitutional shallow donors silicon and oxygen. The visibility of an excited state of the free exciton with a hole from the highest valence band allows to determine the exciton binding energy to 52.4 meV by use of a simple hydrogen model. The resulting band gap energy is 6.094 eV at 10 K. Comparison with earlier reports on homoepitaxial AlN leads to a new identification of the bands reported there.