Abstract

In nanopotentiometry, a conductive atomic force microscope tip is used as a voltage probe to measure the distribution of the electrical potential on a surface.^1,2 We report the application of this technique to a buried heterostructure laser under forward operating bias. The results give insight into a key problem in advanced semiconductor laser engineering: revealing the mechanism and influence of current leakage over the current blocking structure and/or over and around the active region,³ The technique has advantages over other diagnostic methods in that it is nondestructive and, further, does not significantly perturb the device under test; enables characterization of operating, even lasing, devices; and resolves the two-dimensional transverse cross-section of devices, which is particularly important in buried heterostructure devices intended for directly- modulated deployment.

© 2002 Optical Society of America