Finding the Invisible Contaminants in CMOS Image Sensor Pixels: The DCS Technique

This article discusses the basic principles of dark current spectroscopy (DCS), a measurement technique that can detect and identify low levels of metal contaminants in CMOS image sensors. An example is given in which DCS is used to determine the concentration of tungsten and gold contaminants in an image sensor and estimate the dark current generated by a single atom of each metal.