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Ultrahigh-resolution photoluminescence studies of excitons bound to boron in silicon under uniaxial stress.

The effects of uniaxial stress on the no-phonon photoluminescence spectrum ofthe boron bound exciton in silicon have been investigated using ultrahigh-resolution Fourier-transform spectroscopy. Under stresses of 0 to 25 MPa, in the (001), (110), and (111) directions, up to 25 components with linewidths of less than 10 μeV have been resolved. A theoretical model, extending the shell model, has been developed to interpret the splittings in the bound-exciton energy levels. This includes terms expressing electron-stress, hole-stress, electron-hole, hole-hole, and valley-orbit interactions, with spherical and anisotropic corrections