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Of main interest in the present work is a quantitative comparison between the phonon deformation potential (PDP) values determined for silicon single crystals by two different calibration methods: (i) a macroscopic method exploiting the stress field developed in a ball-on-ring (biaxial) bending configuration; and (ii) a microscopic method using the residual stress field stored around an indentation print. A comparison between the two methods helps to establish the reliability limits for experimental stress analyses in the (001), (011), and (111) planes of silicon devices by means of polarized Raman spectroscopy. Emphasis is also placed on evaluating the degree of precision involved with using a closed-form equation (i.e., as proposed by other authors), which describes the stress state when different crystallographic planes of the Si sample are loaded in the ball-on- ring jig. A comparison between stress profiles obtained by such equations and those computed by the finite element method (FEM) in the loaded disk reveals a clear discrepancy for the (011) plane. Such a discrepancy could be attributed to elastic coupling and anisotropic effects (particularly relevant along the <011> direction), which can lead to errors up to 15% in computing the stress field stored in the silicon lattice. [ABSTRACT FROM AUTHOR]

A spatial and tensor deconvolution procedure is proposed for the analysis of cumulative Raman frequency shifts recorded in silicon surface zones containing a Blister-type contact stress field. The procedure is further applied to the quantitative determination of the three independent values of phonon deformation potentials for the Si lattice. Phonon potentials are experimentally obtained for an (110) oriented Si single-crystal containing a pyramidal (Vickers) indentation print. A cross-polarized laser microprobe operating at a visible wavelength enabled us to precisely retrieve the three independent phonon potentials for Si. The presented method requires a minimum amount of material and can be applied with a single measurement set, while previously published characterizations required the availability of relatively large and differently oriented samples. The proposed experimental method is particularly suitable for in situ assessments of phonon deformation potentials in thin/opaque samples with high refractive index. [ABSTRACT FROM AUTHOR]