Mapping materials properties with Raman spectroscopy utilizing a 2-D detector.

An imaging Raman system based on a 2-D detector and capable of collecting simultaneously 1024 spatially resolved spectra has been constructed. Hardware and software are described which allow real time analysis of the spectral data, leading to a large reduction in the data storage requirements. The analysis yields a 1-D profile (1024 points) across the sample of chemical or physical properties that are distinguishable by their Raman spectral features. Sample translations, along with repeated collection and analysis cycles, allow 2-D maps of chemical or physical properties to be generated rapidly. The spatial resolution and spectral precision are 5microm and 0.16 cm(-1) respectively. Applications to the analysis of phase transformed zones in microengineered zirconias and to measurement of an in situ temperature profile of a single carbon fiber are presented. In a typical application, 66,560 Raman spectra from an 8- x 6-mm area on a partially stabilized zirconia sample were collected and analyzed in 5.4 h to produce a 2-D map of the fraction of tetragonal phase transformed to monoclinic phase during crack propagation.