Failure analysis of vertical cavity surface emission laser diodes

Abstract

Degradation of optical output is known as a major failing mode of oxide confined vertical surface emitting laser diodes (VCSEL). While in most cases these lasers show a rapid degradation, continuously reduced optical output by a wear out process is also possible. Failure analysis is essential for a detailed understanding of VCSEL fails. An analysis flow will be shown, comprising electrical and optical characterization as well as detailed transmission electron microscopy (TEM) inspection. Its usefulness will be demonstrated on the basis of case studies.