The measurements of one hundred 1.3 mu m planar buried crescent (PBC) struc
ture InGaAsP/InP lasers demonstrate that parameters given by the electrical
derivative of varied temperature and the variation of the parameters with
temperature can be used to appraise the quality and reliability of semicond
uctor lasers effectual. By measurement of electrical derivative curves one
can evaluate the quality of epitaxial wafer and chip, find the problems in
the material and the technology, offer the useful information on increasing
the quality and improving the technology of devices. (C) 2000 Elsevier Sci
ence Ltd. All rights reserved.