Premium
Cathodoluminescence Determination of Strain‐Induced Shifts at Microcracks in GaN/AlGaN Multi Quantum Wells
Author(s) -
Norman C.E.,
Hoog R.A.,
Shields A.J.,
Iizuka N.
Publication year - 1999
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/(sici)1521-3951(199911)216:1<375::aid-pssb375>3.0.co;2-c
Subject(s) - cathodoluminescence , materials science , quantum well , piezoelectricity , electric field , stack (abstract data type) , optoelectronics , condensed matter physics , laser , optics , luminescence , composite material , physics , quantum mechanics , computer science , programming language
A series of GaN/Al 0.65 Ga 0.35 N multi quantum wells (MQWs) with varying QW width have been investigated. Uncapped MQWs exhibit long microcracks (μ‐cracks) and short nano‐grooves. Significant modification of the strain in the MQW is observed as it approaches a μ‐crack, representing a change from unstrained QWs with strained barriers, to compressively‐strained QWs with slightly relaxed barriers. Good agreement between experimental and calculated values of MQW emission are achieved for both strain configurations by considering only field sharing and the piezoelectric effect as a source of electric field in the QWs. The field sharing arises from a redistribution of free charge in the MQW stack as a result of equalisation of the Fermi level on both sides of the MQW.