大功率氮化镓绿光激光器的材料生长与物理机制

激光显示技术等应用迫切需要高性能大功率GaN基绿光激光器，但目前GaN基绿光激光器还存在效率低、光功率小等问题，是下游相关技术发展的瓶颈。大功率绿光激光器面临的难点包括有源区内量子效率低、光谱展宽严重、空穴注入难、内部光损耗大、器件物理问题复杂、激光器串联电阻高等。相关材料生长研究还相对匮乏，同时其器件物理研究还很薄弱。本项目拟开展GaN基绿光激光器的材料生长和物理机制基础研究，研究绿光激光器InGaN量子阱有源区的生长动力学与缺陷控制；研究绿光激光器的受激辐射过程和物理机制；研究绿光激光器的结构设计与器件制备。阐明InGaN量子阱的In原子偏析与光谱展宽、缺陷形成的关联机制，揭示绿光激光器中的载流子输运、复合过程及其调控方法，阐明绿光激光器的损耗来源与抑制方法，研制出光功率大于1W的GaN基绿光激光器。

High power GaN-based green laser diodes (LDs) are desirable for laser display. However, current GaN-based green LDs are still inefficient and low output power, which limits the development of down-stream technology. The difficulties to fabricate high power GaN-based green LDs include low internal quantum efficiency, inhomogeneous broadening, poor hole injection, high internal loss, complex device physics and high series resistance. Studies on epitaxy and physics of GaN-based green LDs are relatively few. We plan to study the epitaxy and physics of GaN-based green LDs, including epitaxy and defect control of InGaN MQW active region, stimulated emission and physical mechanism of GaN-based green LDs, design of epitaxial layer and fabrication. We will elucidate the link between In segregation and inhomogeneous broadening as well as defect formation in InGaN MQWs. Moreover, we will clarify carrier transport, recombination and the approaches to modulate them. Finally, we will disclose the origin of internal loss and how to suppress it. Our goal is to obtain GaN-based green LDs with 1 Watt output power.