Strain relaxation by 〈100〉 misfit dislocations in dilute nitride InxGa1–xAs1–yNy/GaAs quantum wells

✍ Scribed by E. C. Young; A. N. Koveshnikov; S. Tixier; K. L. Kavanagh; T. Tiedje

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 337 KB
• Volume: 202
• Category: Article
• ISSN: 0031-8965
• DOI: 10.1002/pssa.200521092

✦ Synopsis

Abstract

The effect of dilute N alloying and Bi surfactant growth on strain relaxation in highly strained InGaAs single quantum well (QWs) was investigated by using high resolution X‐ray diffraction (HRXRD) and transmission electron microscopy (TEM). Dilute nitride In~x~Ga~1–x~As~0.99~N~0.01~ QWs of varying thickness, constant lattice mismatch 1.7%, were grown by molecular beam epitaxy on oriented GaAs (001) substrates. Some samples were exposed to a flux of Bi surfactant during the growth procedure, which acts to enhance the N incorporation, increase the optical emission, and create smoother interfaces. The QWs were observed to relax through the formation of pure edge‐type, misfit dislocations aligned with in‐plane 〈100〉 directions. These were found to be directly associated with degradation in the optical emission, however, 1% N addition, with or without Bi surfactant, did not have a detectable effect on the critical thickness nor the rate of this relaxation mechanism. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)