Photoluminescence of excitons bound to the isoelectronic hydrogen-related defects B80(1.1470 eV) and B191(1.1431 eV) in silicon.

Abstract

Photoluminescence spectra of excitons bound to isoelectronic defects ${\mathit{B}}_{80}$ and ${\mathit{B}}_{19}^{1}$ (1.147 00- and 1.143 14-eV principal no-phonon lines, respectively), created in phosphorus-doped silicon grown in a hydrogen atmosphere as the result of irradiation by thermal neutrons, were investigated in magnetic fields up to 12 T and under uniaxial stress in 〈001〉, 〈111〉, and 〈110〉 crystallographic directions using high-resolution Fourier-transform spectroscopy. The symmetry of these defects was determined to be ${\mathit{C}}_{1}$. The ground state of the bound excitons is split into a triplet. The lowest state, which is not evident in the zero-field spectra, results in an additional spectral component under applied magnetic field. Using group theory, we constructed a Hamiltonian for excitons bound to the isoelectronic centers ${\mathit{B}}_{80}$ and ${\mathit{B}}_{19}^{1}$, which takes into account electron-hole coupling and interactions with external perturbations. g-factors ${\mathit{g}}_{1/2}^{\mathit{x}}$=1.3, ${\mathit{g}}_{1/2}^{\mathit{y}}$=1.2, ${\mathit{g}}_{1/2}^{\mathit{z}}$=0.6, ${\mathit{g}}_{3/2}^{\mathit{x}}$=0.9, ${\mathit{g}}_{3/2}^{\mathit{y}}$=1.2, ${\mathit{g}}_{3/2}^{\mathit{z}}$=1.7 for ${\mathit{B}}_{80}$ and ${\mathit{g}}_{1/2}^{\mathit{x}}$=1.35, ${\mathit{g}}_{1/2}^{\mathit{y}}$=1.6, ${\mathit{g}}_{1/2}^{\mathit{z}}$=0.7, ${\mathit{g}}_{3/2}^{\mathit{x}}$=0.9, ${\mathit{g}}_{3/2}^{\mathit{y}}$=0.7, ${\mathit{g}}_{3/2}^{\mathit{z}}$=1.56 for ${\mathit{B}}_{19}^{1}$ were determined from the best fit to the experiment.