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Synchrotron radiation has become a valuable tool for many fields of basic research. Several of the methods which were here developed are also suitable for solving industrial problems. Perhaps the most promising ones are the various X-ray techniques, e.g. X-ray absorption spectroscopy (EXAFS and XANES) and X-ray fluorescence. In the following article the theoretical and experimental basis for these techniques is shortly introduced and some instructive examples for such applications for actual industrial problems are dicussed. In the last section, X-ray lithography for the production of microstructures is presented as an example where synchrotron radiation is already today used for industrial production.

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An apparatus for angle-resolved, wavelength-dispersive x-ray fluorescence spectroscopy with synchrotron radiation has been built and tested at the beam line BN2 of the Bonn electron stretcher and accelerator (ELSA). The apparatus is to be used for nondestructive depth profile analysis of ion-implanted semiconductors as part of the multinational Versailles Project of Advanced Materials and Standards (VAMAS) project on ion-implanted reference materials. In particular, the centroid depths of depth profiles of various implants is to be determined by use of the angle-resolved signal ratio technique. First results of measurements on implants of phosphorus (100 keV, 1016 cm−2) and sulfur (200 keV, 1014 cm−2) in silicon wafers using ‘‘white’’ synchrotron radiation are presented and suggest that it should be generally possible to measure the centroid depth of an implant at dose densities as low as 1014 cm−2. Some of the apparative and technical requirements are discussed which are peculiar to the use of synchrotron radiation in general and to the use of nonmonochromatized radiation in particular.

Centroid depth determinations by angle-resolved self-ratio x-ray fluorescence spectrometry on ion-implanted depth profiles have been carried out at a synchrotron radiation source using ‘‘white’’ radiation. For ion implants of phosphorus in silicon wafers at the 1016 cm−2 level, the results are very satisfactory. The wafer temperature can be kept to a tolerable level if the low-energy component is preabsorbed in a suitable filter (foil) and if additionally the specimen is placed in an environment of helium at atmospheric pressure. The helium atmosphere is indispensable also for avoidance of the deposition of adventitious carbon on the specimen surface. Extrapolating from the results obtained so far, one can conclude that (with the specimen properly mounted in a helium atmosphere) centroid depth measurements should be possible also at a few times 1014 cm−2 dose density level.