Fault localization and analysis in semiconductor devices with optical-feedback infrared confocal microscopy.

We report on a cost-effective optical setup for characterizing light-emitting semiconductor devices with optical-feedback confocal infrared microscopy and optical beam-induced resistance change. We utilize the focused beam from an infrared laser diode to induce local thermal resistance changes across the surface of a biased integrated circuit (IC) sample. Variations in the multiple current paths are mapped by scanning the IC across the focused beam.

High-resolution mapping of quantum efficiency of silicon photodiode via optical-feedback laser microthermography.

We map the external quantum efficiency (QE) distribution of a silicon photodiode (PD) sample via a thermographic imaging technique based on optical-feedback laser confocal microscopy. An image pair consisting of the confocal reflectance image and the 2D photocurrent map is simultaneously acquired to delineate the following regions of interest on the sample: the substrate, the n-type region, the pn overlay, and the bonding pad. The 2D QE distribution is derived from the photocurrent map to quantify the optical performance of these sites.

High-contrast microscopy of semiconductor and metal sites in integrated circuits by detection of optical feedback.

High-contrast microscopy of semiconductor and metal sites in integrated circuits is demonstrated with laser-scanning confocal reflectance microscopy, one-photon (1P) optical-beam-induced current (OBIC) imaging, and detection of optical feedback by means of a commercially available semiconductor laser that also acts as an excitation source. The confocal microscope has a compact in-line arrangement with no external photodetector. Confocal and 1P OBIC images are obtained simultaneously from the same focused beam scanned across the sample plane.