This work describes the application of the Lattice Fringe
Spacing Measurement (LFSM) method to the study of complex multiquantum well
heterostructures containing both low-misfit and strain compensated short
period superlattices in barriers and wells, respectively. 90°-wedge
cross-sectional samples have been used. The adequate choice of both
experimental conditions and digitized sampling allows the whole
heterostructure to be visualized and studied in a single High Resolution
Transmission Electron Microscopy (HRTEM) image. Sample preparation and image
processing technique are simple and inexpensive, resulting a fast procedure
particularly suited for the analysis of large areas. By this way, in a
single HRTEM image we have measured, in the growth direction, the lattice
spacings at either side of the multiple grown interfaces as well as the
period variations of both types of superlattices; in addition, we have
measure on the same image the lattice strain in a direction perpendicular to
the growth direction by using the LFSM and the Cumulative Sum methods. We
have observed local lateral variations within the wells, with regions
tensile or compressively strained, while a vestige of the grown SL remains,
indicating the occurrence of a strain induced lateral composition modulation
process spontaneously produced during the growth of strain compensated
short-period superlattices. This is further confirmed in cross-section
prepared by the tripod mechanical polisher method.