Mesa-size dependence characteristics of vertical surface-emitting lasers

The vertical-cavity surface-emitting laser (VCSEL) is the most suitable light source for many optoelectronic applications because of its planar nature. The design of large VCSEL arrays requires accurate modeling of device characteristics. In this paper, we present a thermal model to analyze the dependence of VCSEL threshold current and light-output characteristics on aperture size. For both 850-nm and 980-nm VCSELs, a linear dependence of threshold current on device area is observed for oxidized aperture sizes with diameters between 5 μm and 25 μm. Good agreement between theoretical and experimental light-output characteristics is observed using a simple thermal model.