A system has been designed to measure the thickness of silicon epitaxial material using a scanning Michelson interferometer rather than a conventional dispersive IR spectrometer. The sampling capacity of this system with a 5–6 sec sampling time exceeds that of several dispersive instruments. The long‐term precision on a single machine (3σ) is , where is the film thickness. Computer processing of the reflection interferogram from an epitaxial wafer provides film thickness data by a Fourier transform method. This method is shown to be mathematically equivalent to the method used for dispersion spectrometers as given by ASTM procedure F95‐68T. The two measurements are in agreement within the published interlaboratory precision of the ASTM method: for P‐type material and for N‐type. The lack of moving mechanical parts in the interferometer system contributes to making this type of instrument very reliable. Down time due to system failure has been minimal, and two systems have been in operation a total of over 4 machine years.

Chemischer InformationsdienstVolume 4, Issue 16 Preparative Inorganic Chemistry ChemInform Abstract: DICKENMESSUNG VON EPITAKTISCHEM SI MIT EINEM MICHELSON-INTERFEROMETER PAUL F. COX, PAUL F. COXSearch for more papers by this authorARNOLD F. STALDER, ARNOLD F. STALDERSearch for more papers by this author PAUL F. COX, PAUL F. COXSearch for more papers by this authorARNOLD F. STALDER, ARNOLD F. STALDERSearch for more papers by this author First published: April 17, 1973 https://doi.org/10.1002/chin.197316050AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume4, Issue16April 17, 1973 RelatedInformation

The magnetically induced circular birefringence and dichroism of several bands in the electronic spectrum of ICl have been studed with a resolution of approximately 0.1 cm−1. The frequency dependence is in agreement with predictions based on the semiclassical dispersion formulas provided that each Zeeman component of a single zero-field line is treated separately. The line center is displaced by the Zeeman shift and the intensity is determined by first-order perturbation by the magnetic dipole-moment operator which mixes neighboring J states. Thus, although the qualitative aspects of the semiclassical treatment of the Faraday effect may be extended into regions of the spectrum in the immediate vicinity of sharp-line molecular spectra, the details of the spectrum depend in a very sensitive way on the molecular parameters and the rotational structure of the band.