Strain measurements and Laue diffraction with microbeams

The authors describe a system being developed to use x-rays for spatially resolved measurements of strain, microstructure and composition in thin films. These capabilities are particularly important for improved understanding of electromigration, stress relaxation, and associated reliability issues in microelectronics. the system uses white radiation collimated and focused with a tapered glass capillary, an area CCD detector for measuring Laue patterns, and an energy sensitive Si detector for measuring lattice spacings. Examples are shown of strain measurements for a 4microm thick Al film on a Si substrate with 300 microm and 30 microm x-ray beams; of Laue diffraction from a single grain for a 40 microm thick Al foil with a 0.3 microm x-ray beam; and of x-ray fluorescence mapping for a patterned Cu film with a 30 microm x-ray beam