Study On Ring Semiconductor Light-Emitting Devices

The ring semiconductor light-emitting devices of GaAs-based have been an interesting direction in the field of semiconductor devices. GaAs-based ring semiconductor light-emitting device can be divided into three types of devices of LED, LD and SLD. From the structure design and process fabrication of ring semiconductor to view, the LD and SLD are two classic types of light-emitting devices. The both type’s light-emitting devices have different characteristics:the device of ring LD structure in the optical integration owns excellent characteristics of high-brightness output and high spectral purity; the light-emitting device of high brightness and lasing spectrum output of high-purity has a potential trend to replace LD of DFB and DBR structure. Ring LD is easier preparation than the preparation process of LD of DFB and DBR structure, which is difficult and is not easy to achieve optical path integration, and unable to meet the needs of optical integration; ring SLD has a wide spectrum, good beam quality, strongly suppress lasing ability and high brightness characteristics, but also the process is simple.This thesis is mainly about the study of single ring,single ring integrated with tapered and multi-ring coupling structure of the semiconductor light emitting device. The main contents are as follows:1. From wave equation of the ring resonator to discuss loss of circular curvature of ring device; theoretically analyzes features of the transverse mode and longitudinal mode of the ring semiconductor light emitting device by relevant factors; theory and its theoretical analysis were included in the electric and magnetic fields, CW and CCW electromagnetic field propagation from ring cavity single quantum well light-emitting devices; discussion of single output direction basic theory.2. Structure of ring semiconductor light emitting device was researched and processed by fabrication. Epitaxial material characteristics of special structure ring semiconductor device was designed, grown and valued.the epitaxial materials structure of the ring semiconductor light emitting device was characterized and analysis. Light-emitting device wafer of808nm wavelength ring AlGaAs/GaAs semiconductor materials can get of0.89internal quantum efficiency and1.4cm-1waveguide losses. Their characteristic of threshold characteristics was compared with traditional devices has been significantly improved.3. Different structure SLDs are fabricated and designed. A tilt angle single ring SLD can be up to maximum continuous output power of100mW, its peak wavelength is785nm, and its width at half maximum (FWHM) is24nm; maximum continuous output power of the integrated structure SLD is about400mW, its peak wavelength is808.5nm, its width at half maximum (FWHM) is31nm, and its vertical divergence angle and parallel divergence angle are35.4°nd2.1°, respectively; the SLD of the integrated structure device with8°tilt angle can achieve maximum continuous output power nearly700mW,803.5nm peak-wavelength,36nm-FWHM,and parallel divergence angle of0.9°.4. Multi-ring coupling structure of the integrated semiconductor light emitting device is designed and preparated. far-field parallel divergence angle of the device is2.7°, the output power is up to lOmW, spectral FWHM width is0.3nm at821nm, Q factor is up to2737; discovering that structure of the multi-ring coupling device has the modulation characteristics of current to spectral, modulation range is close to10nm; and it can achieve a certain injection current modulation effect to its spectrum width, and its capacity of modulation is about0.1nm. The process and device structure are optimized, the output slope efficiency is improved significantly,0.2nm-linewidth can be reached, Q factor is up to4040.