针对大光腔结构往往导致阈值电流密度增大的矛盾，设计了一种具有较高势垒高度的三量子阱有源区。采用非对称宽波导结构的半导体激光器，该激光器在实现大光腔结构的同时保持阈值电流密度不增加。通过金属有机物化学气相沉积(MOCVD)生长InGaAs/AlGaAs三量子阱有源区以及3.6 μm超大光腔半导体激光器的外延结构。结合后期工艺，制备了980 nm脊形边发射半导体激光器。在未镀膜情况下，4 mm腔长半导体激光器阈值电流为1105.5 mA，垂直发散角为15.6°，注入电流为25 A时的最大输出功率可达到15.9 W。测试结果表明：所设计的半导体激光器在有效地拓展光场，实现大光腔结构的同时，保证了激光器具有较低的阈值电流。

In order to solve the contradiction between large optical cavity (LOC) and low threshold current, a new semiconductor laser which has three quantum wells with higher barrier and asymmetric broad waveguide structure is designed. The laser can sustain low threshold current with large optical cavity. GaAs/AlGaAs three quantum wells and 3.6 μm super large optical cavity waveguide are grown by metal organic chemical vapor deposition (MOCVD). The 980 nm semiconductor laser is fabricated. As a result, the threshold current of 4 mm LOC semiconductor laser is 1105.5 mA and the vertical divergence angle is 15.6°. An output power of 15.9 W is reached with injection current of 25 A. The results show that the designed structure is effective for light field expanding, which can realize large optical cavity and guarantee low threshold current.