Electrical-thermal-optical equivalent circuit modeling of vertical-cavity surface-emitting lasers for package-level simulation

In this paper, we report development of an equivalent-circuit electrical-thermal-optical (ETO) model for VCSELs suitable for coupling to package-level thermo-mechanical CAD software using Analogy´s Saber state-of-the-art circuit simulator platform as an interface. The model treats the rate equations for the photon number S and the carrier number N combined with the thermal rate equation. The temperature dependence of the threshold current is partitioned into a constant value of threshold current under low-duty-cycle pulsed conditions and an empirical thermal offset current I/sub off/(T). For simplicity, I/sub off/(T) is modeled using a polynomial function of temperature.