Microwave characterization of vertical cavity surface emitting diode laser and transistor laser

Semiconductor lasers are widely deployed in optical transceivers for optical fiber based short-reach (< 100m) data links. With increasingly growing data traffic worldwide in data centers, developments of faster optical transceivers, hence high-speed semiconductor lasers, are highly demanded. The vertical cavity surface-emitting laser (VCSEL) is the most commercially popular choice. With high reflectivity DBR mirrors and oxide-confinement for emission mode control and leakage current reduction, VCSELs are able to achieve a low laser threshold and high modulation bandwidth. Currently in published research results, the highest data transmission rate demonstrated for an 850 nm VCSEL is 57 Gb/s error-free at 25 °C and 50 Gb/s error-free at 85 °C. Nevertheless, the bandwidth and data transmission performance of diode lasers, such as VCSELs, are fundamentally limited by the slow spontaneous recombination lifetime. Therefore, a new kind of semiconductor laser, the transistor laser (TL), is proposed to break the bandwidth bottleneck as the dynamic carrier transport in the base of a TL drastically reduces the spontaneous recombination lifetime. Ultimately to reach low threshold and high energy per bit efficiency, the first oxide-confined vertical cavity transistor laser (VCTL) is realized with a trench oxidation process and a lateral-feeding base metal design. To further reduce the excessive emitter series resistance, a VCTL with partially etched mesa is developed and fabricated. The tunneling modulation aspect and possible application of the TL is also explored in this dissertation