Thermal modeling of transferred VCSELs

Vertical cavity surface emitting lasers (VCSELs) are an important light source for applications in communication and appliances consumer use. However, the types of III-V semiconductor materials that can be used to manufacture monolithic VCSELs are limited to only few choices. Moreover, limitations of the device materials will also limit the functionality of VCSELs incorporated into microsystems. Various heterogeneous integration approaches have been developed to overcome this limits [1, 2]. We previously demonstrated a bonding approach onto foreign substrates which incorporates fully fabricated VCSEL arrays which do not require additional processing after bonding and optical characteristics are maintained after the bonding process [3]. In this work we report VCSEL thermal modeling using COMSOL simulations to investigate the relation between laser performance and temperature. Good agreement is obtained between simulation and experiments for VCSEL lasing wavelength with varying oxide aperture and mesa size under operation near maximum output power. Using this model, the thermal rollover at peak output power of VCSELs on different substrates is discussed.