Patent ID: 8198112

Claim:
A process of manufacturing a semiconductor laser diode comprising a gain section, a QWI output window, and QWI waveguide areas, wherein: the semiconductor laser diode is characterized by a lasing wavelength λ L ; the QWI waveguide areas are fabricated using quantum well intermixing and define a QWI waveguide portion in the QWI output window of the laser diode; the QWI output window is transparent to the lasing wavelength λ L ; the QWI waveguide portion in the QWI output window is characterized by an energy bandgap that is larger than an energy bandgap of the gain section such that the band gap wavelength λ QWI in the QWI waveguide portion and the QWI output window is shorter than the lasing wavelength λ L ; the QWI output window is characterized by a photoluminescent wavelength λ PL ; and the manufacturing process comprises a λ PL screening protocol that determines laser diode reliability based on a comparison of the lasing wavelength λ L and the photoluminescent wavelength λ PL of the QWI output window.