Research on the fabrication of high-power semiconductor lasers by impurity-free vacancy disordering

The preparation of a non-absorption window (NAW) through impurity-free vacancy disordering (IFVD) induced quantum well intermixing (QWI) in 915 nm GaInAsP/GaAsP semiconductor lasers is aimed at enhancing the catastrophic optical mirror damage (COMD) threshold and output power of semiconductor lasers. A process for the fabrication of high-power semiconductor lasers has been explored through the intermixing study of primary epitaxial wafers. In the experimental procedure, the epitaxial layers at the front and rear facets were first selectively etched, followed by the deposition of a 200 nm SiO2 dielectric layer on their surfaces. Additionally, a 100 nm TiO2 dielectric layer is applied to suppress QWI in the gain emission region. A NAW is achieved through a rapid thermal annealing process at 830°C for 180 s under atmospheric pressure. In the wafer-scale fabrication process, wide-stripe single-tube devices are produced with a light-emitting region width of 200 μm and a cavity length of 4000 μm. Test results reveal that conventional single-tube devices typically experience COMD at an input current of ∼20 A, with power output at around 19 W. In contrast, the single-tube devices with the NAW reach a continuous output power of 27.7 W at an input current of 30 A, representing a power enhancement of ∼45.8 % . No optical catastrophic damage is observed, and characteristics, such as slope efficiency and threshold current, remain unaltered. This research demonstrates that IFVD combined with the wafer-scale fabrication can effectively enhance the COMD threshold of 915 nm GaInAsP/GaAsP semiconductor laser devices, offering valuable insights into the study of high-power semiconductor lasers.