POSITION-SENSITIVE ATOM PROBE ANALYSIS OF MULTI-QUANTUM WELL STRUCTURES

Abstract
The Position-Sensitive Atom Probe (POSAP) has been used to examine a number of InP based quantum well structures in order to elucidate the chemistry and morphology of the interfaces between wells and barrier layers. The interfaces are of critical importance in determining the performance of devices manufactured from such structures. Results have been obtained from three sets of GaInAs/InP wells ; all the material was grown by Metal-Organic Chemical Vapour Deposition (MOCVD). The information obtained in these observations will be useful in gaining a fuller understanding of the growth processes of these materials, and, because of good agreement with TEM and HREM, in refining the models used to interpret data obtained with these techniques and with the standard assessment methods of X-ray diffraction and photoluminescence.