Remote plasma enhancecd chemical vapor deposition techniques have been developed for a wide variety of processes. These include SiO2, Si3N4, Si, Ge, GaN, GaAs, and a-Si:H depositions. This development has been enabled through the use of electron diffraction and electron spectroscopy techniques. These techniques have been used to qualify cleaning procedures prior to epitaxial or dielectric depositions. They have beeii used to qualify epitaxial deposition conditions by defining suitable.temperature and rate conditions. And, they have been used to evaluate cross-contamination issues. In situ techniques have been used in conjunction with ex situ characterizations to identify and correct problems in wafer cleaning, epitaxy, and process integration.