Theoretical Analysis and Experimental Research on Widely Tunable SGDBR Laser Diode

Widely tunable semiconductor lasers are a very important class of semiconductor optoelectronic devices, due to significantly reduce the number of spare lasers are ideal light source of optical fiber communication DWDM system and will also play in the future intelligent optical network an increasingly important role. In addition, in the field of measurement and sensing, wide tunable semiconductor lasers have very broad application prospects. Which sampled grating distributed Bragg reflector (Sampled Grating Distributed Bragg Reflector, SGDBR) semiconductor laser due to the wide tuning range, spectral quality, fast wavelength tuning, functional scalability wide concern. The dissertation wide tunable semiconductor lasers developed SGDBR to carry out the following work: design and optimize the structure of the sampled grating laser. Detailed discussion of the sampling length of the sampled grating structure parameters such as the number of the sampling period, duty cycle, and facet reflection, given the characteristics of the grating reflection spectrum and laser performance, including tuning range, output power and side mode suppression ratio optimization results. Analog design of the laser active region and a passive region material, computing a multiple quantum well active region of the energy band structure and the gain spectrum, the different range of refractive index variation of the band gap material and the corresponding absorption loss calculations. And two different section of the optical field distribution, refractive index matching, and overlap integral simulation study. 3. Establishment of a new type of dynamic analysis models, different model according to the different characteristics of the laser active region and the passive zone: the active region of the laser still use the traditional time-domain traveling wave method; rather complex structure passive region is first using frequency-domain analysis methods, and then through a digital filter to effectively combine both methods; using the model of the semiconductor laser of SGDBR static and dynamic characteristics, particularly the wavelength switching performance analysis, and further the The model is extended to the dynamic characteristics of the integrated device research. 4 Cl2/H2 as the etching gas, through the measurement of multiple quantum well light-fluorescence intensity, and the detailed analysis of various parameters of the surface damage of the material in the ICP plasma etching apparatus, including the pressure, ICP power, RF power, and engraved eclipse gas component, which summed up the high-density plasma low-damage etching law. According to the results, obtained under conditions of low-damage etching etching morphology. The application of this process to the actual laser process, the production of the DFB laser output characteristics and aging test results proved the reliability of the process, and further used to improve the production process of the sampled grating. Controlling and repetition rate; while improving MOCVD MOCVD docking process research the pure wet etching from the docking interface corrosion program to improve the combination of dry etching and wet etching, corrosion interface The growth process, significantly improving the quality of the material growth and to achieve the growth of a high quality of the docking between the waveguides. In support of the theoretical design and supporting technology, the actual production width is tunable SGDBR semiconductor laser; take advantage of the Precision Reflectometer measuring docking interface residual reflected in the 10-4 middleweight; simultaneously on overcome the SGDBR semiconductor laser structure inherent the adverse impact of the defects on the laser performance, carry out the integrated SOA devices SGDBR semiconductor laser research work. 7 using LabVIEW software lasers automated test systems, test results show that the device developed by the quasi-continuous tuning range greater than 35nm, side mode suppression ratio greater than 30dB entire tuning range. In addition, test results show that by the introduction of SOA effective in improving the uniformity of the output power between the respective output channels, and the wavelength of the device switching characteristic measurement of the integrated device. The test results show that the the SGDBR semiconductor laser lasing wavelength switching from 1541.92nm to 1546.76 nm only a time of about 6.2 ns. Major innovation in this paper include: Ⅰ systematic analysis of various structural parameters and grating reflection spectrum characteristics of the sampled grating, as well as the performance of laser tuning range, output power and side mode suppression ratio; These results come before the group SGDBR semiconductor laser, after sampling the optimized parameters of the grating. II established a new type of dynamic analysis model. Model according to the different characteristics of the laser active region and the passive zone, using a different approach: the laser active region still use traditional time-domain traveling wave method using frequency domain; First, the complex structure of the passive zone analysis method, then through a digital filter to the traveling wave method of time-domain and frequency domain methods effectively combine; model SGDBR semiconductor laser static and dynamic characteristics, especially the laser wavelength switching performance analysis, and the further The dynamic characteristics of model extended to more complex integrated devices. Ⅲ on the high-density plasma etching damage to start the study. Study with Cl2/H2 when ICP etching system parameters on the material surface damage, summed up the law of etching damage; This result is introduced into the process of DFB semiconductor lasers, laser optical performance and aging test results show that the reliability of the process, and further used for sampling grating production process improvements. Ⅳ studies butt MOCVD growth process, has two options, the corrosion process of the docking interface corrosion from the initial pure wet to dry and wet combined, and further improvements in the MOCVD growth program, improve the docking process reliability and repeatability. Collection of the research, including MOCVD docking process the sampling grating production process and the theoretical model optimized results, the actual production SGDBR semiconductor laser devices. And inherent defects in the laser structure, making the SGDBR semiconductor lasers integrated SOA devices, effectively improve the uniformity of the output power of each channel as well as to enhance the output power.