A buried tunnel junction 940 nm VCSEL for achieving thermal diffusion characteristics

To investigate the performance degradation of a vertical-cavity surface-emitting laser (VCSEL) caused by self-heating effects, a 940 nm VCSEL with a buried tunnel junction (BTJ) and an aperture size of 10 μm was designed. The BTJ-type VCSEL achieves a 39.38% higher peak power (19.96 mW), a 3.26% higher peak power conversion efficiency (46.41%), and a 24.97% lower differential resistance (37.32 Ω), and the thermal rollover current is delayed to 6.07 mA than conventional design. When the injection current is 20 mA, the BTJ-type VCSEL exhibits a low temperature and Auger recombination rate, while the stimulated recombination rate is high. In addition, the BTJ-type VCSEL shows a small far-field divergence angle and good beam quality. Therefore, the designed BTJ-type VCSEL offers valuable guidance for the preparation of high-reliability and long-lifetime VCSEL.