Semiconductors and electronic materials have benefitted from photoacoustic and photothermal techniques since the late 1970s. This volume, the fourth in a series on photothermal and photoacoustic science and technology (PPST), presents a comprehensive review of the diverse progress made in PPST of semiconductors and electronic materials during the 1990s. The 10 chapters review leading research activities in several subfields of PPST. These include applications of novel analytical and/or experimental techniques to traditional semiconductor materials and devices as well as applications of conventional techniques to novel materials and devices. As with other volumes in the series, this text is useful as a reference for practising scientists and engineers and as a supplement to upper-level graduate courses in various areas of PPST and its subfields.