Study On High-Power Semiconductor Laser Diode Bars

Semiconductor laser has an important role in the development of national economy because of its small bulk, little weight, high efficiency and long life time. High power laser diode array is mainly used as the pumping energy source for solid state laser. There is the need for high duty-cycle laser diode array to satisfy the demand the DPSSL (diode pumping solid state laser) technology. Now to build the modernization of industry and national defend, DPSSL is developing quickly in whole country. So largely developing high power laser diode array is meaning for the fast development of economy, the modernization of national defend and the promotion of people's life. In reality with the projects development, the output power of the semiconductor laser bars are needed more higher, scientists are always do their best to improve the reliability and output power of the lasers. But owing to the small volume of the active layer, output power is enslaved to the COD. Generally, single P-N junction have mW order, the best is 1-3W until now. So to get higher output power, the only method is to adopt SLD array.In this paper, we firstly introduce basic concept, including the characteristics of the strain quantum well lasers, coupled mold theory of high power semiconductor laser bars, thermal losses mechanics, we also analyse them and get the source of heat of the laser bars and its thermal performance. To carrying out high output power, low threshold current density and high efficiency of electricity to light, we main from two sides of InGaAs/GaAs strain quantum well lasers optimize designs and theory analyse. We discussed the material design and chip structure design, the fomer include the ply of every layer of the epitaxial wafer, the component of every layer and doping content of every layer; the latter include the layout of the laser bars and the duty ratio of the bars. We also find the right technology steps and introduce the main technology including photoengraving, ICP and sputter. In the end, we do the experiment on the packaging bars.I n the process of technology of the laser bars, the relationships of the etch depth and bar's parameter have been studied. We find the rule between them and the relative best etch depth, it's very important in the process of the technology. The production of the laser bars are more complex than general lasers, we also find the relative best steps of laser bars. Packaging technology plays an important role in the high power semiconductor laser bars. We deeply study the most advanced technology of the packaging technologies of the laser bars, for example, micro channel heat sink. We do the experiment and do some analyse about it.