Technique Renders High-Contrast Images of Semiconductor Sites

A procedure combining optical-beam-induced current imaging and scanning confocal microscopy has produced high-contrast images of semiconductor sites on an integrated chip. Although imaging optically induced current is an effective method for detecting failure or defects on chips, the images typically carry low contrast. Researchers with the National Institute of Physics at the University of the Philippines in Quezon City obtained both optically induced and confocal images from the same focused beam and integrated the data with a simple algorithm to render high-contrast (axial dependent) maps of semiconductor sites in the confocal image.

Similar images are possible with multiphoton microscopes, but the technique, described in the July 10 issue of Applied Optics, achieves comparable results with less-expensive confocal instruments.