LASER CHARACTERIZATION SYSTEM AND PROCESS

摘要

A system and process for automatically characterizing a plurality of external cavity semiconductor laser chips on a semiconductor laser bar separated from a semiconductor wafer. The system includes a diffraction grating mounted on a rotary stage for rotating the diffraction grating through a range of diffraction angles; a steering mirror mounted on the rotary stage and oriented perpendicular to a surface of the diffraction grating; and a laser analyzer; and a laser bar positioning stage. The positioning stage is automatically moved to aligning each laser chip in a laser bar on the stage, one chip at a time, with the diffraction grating, such that a part of the laser beam emitted from a laser chip in a laser bar is reflected back to the same laser chip by the 1st order diffraction of the grating to lock the lasing wavelength and the rest of the laser beam reflected by the steering mirror is received and characterized by the laser analyzer. For each laser ship, the rotary stage is automatically rotated to rotate the diffraction grating through a range of diffraction angles relative the laser beam emitted by the laser chip, and the laser analyzer automatically characterizes the laser optical properties such as spectra, power, or spatial modes at each diffraction angle.