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在(0001)蓝宝石衬底上分别用金属有机化学气相沉积技术外延生长了InGaN/GaN,InGaN/In-GaN,InGaN/AlInGaN多量子阱激光器结构,并分别制作了脊形波导GaN基激光器。同步辐射X射线衍射,电注入受激发射光谱测试及光功率-电流(L-I)测试证明,相对于GaN垒材料,InGaN垒材料,AlInGaN四元合金垒材料更能改善多量子阱的晶体质量,提高量子阱的量子效率及降低激光器阈值电流。相关的机制为:组分调节合适的四元合金垒层中Al的掺入使得量子阱势垒高度增加,阱区收集载流子的能力增强;In的掺入能更多地补偿应力,减少了由于缺陷和位错所产生的非辐射复合中心密度;In的掺入还减小了量子阱中应力引致的压电场,电子空穴波函数空间交叠得以加强,使得辐射复合增加。
InGaN / GaN, InGaN / In-GaN and InGaN / AlInGaN MQWs were epitaxially grown on (0001) sapphire substrates by metal organic chemical vapor deposition. Waveguide GaN-based lasers were fabricated. Synchrotron radiation X-ray diffraction, electron injection stimulated emission spectroscopy and optical power-current (LI) tests show that, compared with GaN barrier materials, InGaN barrier material and AlInGaN quadruple barrier material can improve the crystal quality of multi- Improve the quantum efficiency of the quantum well and reduce the laser threshold current. The related mechanisms are as follows: the component adjusts the incorporation of Al in a suitable quaternary alloy barrier layer, which increases the barrier height of the quantum well and enhances the ability of the well region to collect carriers; the incorporation of In can more compensate stress and reduce The density of non-radiative recombination centers due to defects and dislocations; the incorporation of In also reduces the piezoelectric field caused by the stress in the quantum well, and the spatial overlap of the electron-hole wave function is strengthened to make the radiation recombination increase.