808 nm半导体分布反馈激光器的光栅设计与制作

半导体分布反馈（ DFB）激光器的核心工艺之一是分布反馈光栅的制作，设计了808 nm DFB激光器的一级光栅结构。利用纳米压印技术与干法刻蚀附加湿法腐蚀制作了周期为120 nm的梯形布拉格光栅结构，使用MATLAB和Pics3D软件模拟了一次外延结构的光场分布和能带图。通过优化湿法腐蚀所用腐蚀液各组分比例、腐蚀温度、腐蚀时间等条件，得到了理想的湿法腐蚀工艺参数。扫描电子显微镜表征显示，光栅周期为120 nm，光栅深度约为85 nm，占空比约为47%，光栅边缘线条平直，表面平滑，周期均匀。创新型的引入湿法腐蚀工艺和腐蚀牺牲层使光栅表面的洁净度得到保证，提高了二次外延质量的同时，也为进一步制作DFB激光器高性能芯片奠定了良好的基础。

Design and preparation of grating for 808 nm semiconductor distributed feedback laser

One of the core processes of semiconductor distributed feedback lasers was the fabrication of distributed feedback gratings, and the first-order Bragg grating structure of 808 nm distributed feedback semiconductor was designed. A trapezoidal grating structure with a period of 120 nm was fabricated by using nanoimprint technology combined with process of dry etching and wet etching. The optical field distribution and energy band diagram of epitaxial structure were simulated using MATLAB and Pics3D software. The ideal wet etching process parameters were obtained by optimizing the proportions of corrosion components used in wet etching, corrosion temperature and corrosion time. The scanning electron microscopy measurement shows that the grating has a period of 120 nm, depth about 85 nm, duty cycle about 47%, and the grating has the advantages of straight edges, smooth surface and even period. The innovative introduction of the wet etching process and the corrosion sacrificial layer ensures the cleanliness of the grating surface, improves the secondary epitaxial quality, which lays a good foundation for the further production of high-performance chips for distributed feedback lasers.