Results of quantitative spectroscopic analysis of packaging-induced
strain in In0.06Ga0.86Al0.08As/Ga0.7Al0.3As/GaAs
high-power ‘cm-bars’ diode laser arrays are presented. Theoretically,
the influence on the results of particular device structure properties,
such as intrinsic strain, is analyzed. We compare these theoretical
results, which are based on a unaxial stress model, with photocurrent
data. For In-soldered devices on copper heatsinks, we find a strain
difference of (0.050 ± 0.015)% between edge and center of the
device. Almost complete strain-relaxation toward the device edges is
experimentally demonstrated. The general approach is also applicable
to the analysis of all data that refer to changes of the electronic
bandstructure, such as absorption and photoluminescence.