Another dimension in device characterization

Recent years have witnessed rapid progress in the area of high-resolution characterization of silicon devices by scanning capacitance microscopy (SCM). It is timely to discuss the applications of this technique in a broader context by addressing other types of devices and materials. This article represents a step towards this objective and will review our SCM work focusing on advanced InP-based laser structures. The basic principles involved in the SCM methodology are introduced, including resolution. The specific topics that will be covered include SCM analysis of regrowth on patterned substrates, different types of InP-based buried heterostructure (BH) lasers, and complex-coupled distributed feedback (CCCDFB) lasers. The behavior of the SCM signal in the different material and device-specific contexts is discussed, and device processing issues are highlighted. We also comment on the necessary factors for bringing the SCM technique to a level that can directly contribute to advanced III-V device technology.