| With the increasing demand of the bandwidth, the optical networks have been gradually applied in the enterprise network and the access network. In order to apply the optical networks in the short-range and intermediate range more widely, the optoelectronic devices should be low cost, high speed and low consumption. Because of the shortcomings such as the high testing cost, high precision for alignment, low coupling efficiency and high driving current, the conventional edge emitting lasers will not meet the requirement of the future optical networks in the short and intermediate range links. Therefore, much effort was applied to explore the new low cost, high speed and low consumption light sources. The vertical cavity surface emitting lasers (VCSELs), with super advantages such as wafer level testing, high coupling efficiency to the optical fiber, high modulation capability and low consumption and so on, are the most promising and competitive light sources in the short and intermediate optical networks. Whereas the 850nm VCSEL has been successfully used in the short range multiple mode fiber networks, as the more suitable light source in the short and intermediate single mode optical networks, recently the 1310nm VCSEL has been investigated widely.In this paper we studied the distributed Bragg reflector (DBR), quantum well (QW) active region and the thermal effect of the optoelectronic characteristics of the VCSEL. At the structure design of the 1.3 u m GaInNAs VCSEL, we proposed three approaches to improve the device performance. Firstly, as the GalnNAs material quality degrades rapidly with the increasing nitrogen content, the Gao.65Ino.35No.01Aso.99/GaAs quantum well of the 1.3 um GalnNAs VCSEL was designed to improve the material gain. Than the QW gain peak wavelength could designed to be close to the 1.3 u m and it is easier to grow the high quality GaInNAs/GaAs QW by MOVPE. Secondly, in order to reduce the device resistance, the heavily doping density in graded regions at the standing wave nodes and the light doping density in graded regions at the antinodes were utilized to decrease the barrier at the interface and the resistance. Therefore the thermal effect from the joule heat could be decreased. To reduce the mirror loss, the low doping density in bulk regions was chosen to decrease the optical absorption. Thirdly, since the gain peak wavelength shifts faster than the VCSEL emission wavelength with temperature, the offset between the gain peak wavelength and the emission wavelength was optimized to obtain the good match, which will improve the performance of the 1.3 u m GalnNAs VCSEL.By optimizing the design of the distributed Bragg reflector (DBR) and matching betweenthe gain of the GaAs/AlGaAs Quantum well and the emission wavelength, the high performance 850nm oxide-confined VCSEL was fabricated. The threshold currents of 850nm VCSEL were below 2mA. The slope efficiencies were between 0.5 mW/mA and 0.6mW/mA. The peak power exceeded 11mW at room temperature and the series resistances were below 45. The device can work up to 85C. The values of these optoelectronic characteristic parameters were not only the best reports for the 850nm VCSEL at home but also among the best reports for the 850nm oxide confined VCSEL.Through the above three approaches, we optimized the structure of the 1.3 u m GaInNAs VCSEL and fabricated the performance-improved 1.3 u m GalnNAs VCSEL. For the the 2 X 2.8 u m2 aperture single mode VCSEL, at room temperature the threshold current was 1.0mA and the lasing wavelength was 1283.9nm. The forward voltage at 6mA was 3.3V. The maximum power was 0.256mW. The side-mode suppression ratio (SMSR) was 46.53dB at 6.5mA; For the 5 X 6 u m2 aperture single mode VCSEL, the threshold current of was 2mA at room temperature and the SMSR exceeded 40dB. These results were the best reports for the 1.3um GalnNAs VCSEL with the direct contact structure. For the 5x6um2 aperture multiple mode VCSEL, the threshold current of was 1.53mA and the the slope efficiency was 0.12mW/mA at room temp...
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