This letter reports a successful fabrication of room-temperature electrically injected AlGaN-based near-ultraviolet laser diode grown on Si. An Al-composition step down-graded AlN/AlGaN multilayer buffer was carefully engineered to not only tackle the huge difference in the coefficient of thermal expansion between AlGaN template and Si substrate, but also reduce the threading dislocation density caused by the large lattice mismatch. On top of the crack-free n-AlGaN template, high quality InGaN/AlGaN quantum wells were grown, sandwiched by waveguide and optical cladding layers, for the fabrication of edge-emitting laser diode. A dramatic narrowing of the electroluminescence spectral line-width, an elongated far-field pattern, and a clear discontinuity in the slope of light output power plotted as a function of the injection current provide an unambiguous evidence of lasing.

中文翻译：

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Si上生长的室温电注入AlGaN基近紫外激光器

这封信报道了在硅上生长的室温电注入AlGaN基近紫外激光二极管的成功制造。精心设计了一种由Al组成的逐步降级的AlN / AlGaN多层缓冲液，不仅可以解决AlGaN模板与Si基板之间热膨胀系数的巨大差异，而且还可以减少由大的晶格失配引起的穿线位错密度。在无裂纹的n-AlGaN模板的顶部，生长高质量的InGaN / AlGaN量子阱，将其夹在波导层和光学覆层之间，以制造边缘发射激光二极管。电致发光光谱线宽急剧变窄，远场图形变长，