SPECTROSCOPIC ELLIPSOMETRY FOR THE CHARACTERIZATION OF THIN-FILMS

In the visible range from 250 to 900 nm, a variety of spectroscopic ellipsometers are presently available from different manufacturers. Some of these instruments can be used off-line for thin film characterization, but other instruments are fully compatible with vacuum systems and the in situ study of phenomena such as growth kinetics, thin film deposition processes, and surface adsorption effects. A review of the existing spectroscopic ellipsometers is given as well as an up-to-date ellipsometric configuration still under development, which involves three polarizers. The relative accuracy of this latter instrument is discussed. A review of the applications of this technique in the case of bulk or layered materials and of the problems encountered in the microelectronics industry is given. Spectroscopic ellipsometry can also be performed in the infrared range. Some first results, measured with a prototype of this instrument, are shown in order to demonstrate the degree of sensitivity of this technique. © 1990, The Electrochemical Society, Inc. All rights reserved.