为改善宽面940 nm半导体激光二极管(LD)的输出功率及光电转换效率(WPE)，设计并制作了一种包含梯度渐变折射率(GRIN)结构的新型量子阱激光器。通过二维自洽软件模拟计算了新结构激光器与传统分别限制结构(SCH)激光器的能带结构，结果表明新的激光器结构能够显著消除各异质结间的过渡势垒。通过低压金属有机物化学气相沉积(LP-MOCVD)的方法生长了高质量激光器外延材料。制成后的100 μm条宽、 2000 μm腔长的激光器器件在室温25 ℃下经过连续(CW)电流测试发现，梯度渐变折射率结构激光器较分别限制结构激光器在10 A电流下电压约低0.07 V。通过结构与生长优化，激光器内吸收系数从0.52 cm-1降至0.43 cm-1，最大光电转换效率由69%提升至76%。最终制成的940 nm半导体激光器器件室温25 ℃下输出功率10.0 W(10 A电流时)，斜率效率高达1.24 W/A。

In order to improve the output power and wall plug efficiency (WPE) of the broad area 940 nm semiconductor laser diode (LD), we design and fabricate a new type quantum well LD with a step graded index (GRIN) structure. By using a two-dimensional self-consistent software, the energy band structures of step GRIN structure laser and traditional separate confinement heterojunction (SCH) laser are simulated and compared. The result shows the significant elimination of band offset between heterojunctions in step GRIN structure. High quality laser materials are obtained by using low-pressure metal organic chemical vapor deposition (LP-MOCVD) method. Broad area laser devices with 100 μm wide stripe and 2000 μm long cavity are fabricated and tested under 25 ℃ continuous wave (CW) operation condition. The new step GRIN structure laser diode shows a drop down voltage of 0.07 V at 10 A operation current than the SCH structure laser. By optimizing the design and growth method, the internal loss of step GRIN structure laser is reduced from 0.52 cm-1 to 0.43 cm-1 and the wall plug efficiency is increased from 69% to 76%. The LD chip yields a slope efficiency of 1.24 W/A and 10.0 W at 10 A operation current at 25 ℃ room temperature.