Semiconductor Laser Engineering, Reliability and Diagnostics: A Practical Approach to High Power and Single Mode Devices

Part III

DIODE LASER DIAGNOSTICS

Overview

As diode laser applications continue to demand increasingly higher optical output power and longer lifetime data, the stress on the material, particularly at the susceptible mirror facets, poses an ever-growing technological challenge. That is, it has become both increasingly vital and more intricate to identify and analyze the real root causes of specific performance degradation modes at the ultimate laser operating conditions, at which laser performance and reliability are affected at much lower defect densities. In addition, the growing demand for the highest laser functionality and yield makes it indispensable to develop superior materials and device technologies so that they can excel the current and meet the next generation of laser performance requirements. In this sense, material and device characterization employing powerful diagnostic and analytical techniques within the laser product development process will play an increasingly important role and thus continue to make vital contributions to the advancement of the state-of-the-art.

These diagnostic investigations should be implemented as an integral part of the diode laser development plan. The objective is to reveal potential causes for failures in performance and reliability before the devices are put through life tests and before they are deployed in the field. This proactive and preventive action is in contrast to failure analysis (FA) activities, which are executed only ...