High temperature stability 850-nm In0.15Al0.08Ga0.77As/Al0.3Ga0.7As vertical-cavity surface-emitting laser with single Al0.75Ga0.25As current blocking layer

Abstract

In this paper, we employed a high bandgap Al0.75Ga0.25As layer acting as an electronic blocking layer in the upper In0.15Al0.08Ga0.77As/Al0.3Ga0.7As active region before the growth of p-type layers of 850-nm vertical-cavity surface-emitting lasers (VCSELs). A threshold current of 1.33mA and slope efficiency of 0.53W/A at 25 degrees C were obtained, and the temperature dependent light output and voltage versus current (L-I-V) characteristics showed that the VCSELs with a high bandgap Al0.75Ga0.25As layer were more stable when the substrate temperature was in a range of 25-95 degrees C. The threshold current increased with temperature up to 95 degrees C was less than 21% and the slope efficiency dropped only 24.5%.