Design, Processing and Characteristics Analysis of 850nm Vertical-Cavity Surface-Emitting Lasers

Vertical-cavity surface-emitting lasers(VCSEL) have distinct advantages over conventional edge emitting lasers, such as small divergence angle, single longitudinal mode operation ,very low threshold current, compatible with optical fiber and other optical elements. They have become the ideal light sources for optical interconnections, optical free space communications, optical signal processing and neural networks. In this paper, we give some results on the design and fabrication of 850nm VCSELs, the main work is as follows:First we simply described the theory of VCSEL, and gave special analysis on 850nm high power VCSEL DBR design.A novel semiconductor/superlattice DBR has also been designed. In the experiment, the p-type and n-type DBR with different pairs and at different wavelengths have been grown on an n~+-GaAs(100) substrate with MBE system. From the result, the DBR has low series resistance while retaining high reflectivity.For the VCSEL fabrication, oxide-confined structure provides electrical and optical confinement. The laser wavelength peak is about 840nm. The lowest threshold current of 5mA is achieved. The minimum output power is over 3.5mW.