| The high-power semiconductor quantum well(QW) laser is a kind of luminescence device with superior performance, it has longe-lived, low threshold current density, high efficiency, high luminosity and excellent monochromatic, coherence , directionality, etc. The high-power semiconductor laser is widely applied to the fields, such as military, industrial machining, communication, information processing, medical treatment, etc. The material's epitaxy is the foundation of the whole laser's fabricating, and it has important influence on the optics and electricity performance about the laser. Without the high-quality material , we can not get the the high-performance lasers, so material epitaxy is the most important part in fabricating the semiconductor laser. At present, MOCVD technology has comparative high development level and high epitaxy quality. The study on MOCVD technology has become an important item both at home and abroad too. At present, Chinese Electronic Technology group Corporation NO. 13th Research Institute Photoelectricity Department have an AIXTRON-2000 MOCVD device which has a leading level in the world, and they got a large amount of research results in the research of the quantum well laser, has abundant practical experience. So, all that permit us to go on with our research about the technology of MOCVD.In this paper, the epiwafer which lasing wavelength was 940nm grown by MOCVD was reported. It adopted Separation Confinement Heterostructure Single Quantum Well (SCH-SQW) structure, the quantum well material was In0.15Ga0.85As, the quantum well's thickness was 80A which was received by calculation. Then we grew the material with different active layer growth temperature, different v/Ⅲ ratio, different doping concentration and form. After that, we tested these materials by photoluminescence(PL) technology, and got the best growth condition according to the results of photoluminescence spectra. Our result was that the active layer growth temperature was 700℃, V/Ⅲ ratio was 60, waveguide layer doping was gradual changed(n-type doping with SiH4 from 190sccm to 590sccm, p-type doping with DMZn from 90sccm to 490sccm). At these conditions, the material growth by MOCVD has the better opticsand electricity performance.In addition, This paper has analyzed and calculated the wave-guide mode theory, got the quantum well laser photic-field distribution's fluctuation equation, deduced the far-field distribution's mathematics model by the method of stepwise approached, and simulated the near-field and far-field about the laser with computer software. We utilized a pair of mode expand layers which can restricted in photic-field to narrowed the far-field comer about quantum well laser material structure (the corner was about 21?. For the wave-guide of SCH-SQW 940nm quantum well laser, we used this way to simulate and compare, got the far-field corner 35.8° when the Al percent was 25% and wave-guide's thickness was 150nm. Compare with the results former, this value was improved much.After got the growth and structure parameters, we had fabricated the laser with these optimal parameters. After a series of operations, we got the semiconductor laser array which was 1cm bar. An output power of 106.3W with frequency of 500Hz,pulse width of 100 w s and duty-cycle of 5% was achieved at room temperature, and the slope efficiency of the bar was 1.019W/A, the highest electrical-to-optical efficiency was 43.3%, the far-field corner was 37.1°, a little higher than the simulated number.
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