Shallow Donor Electrons in Silicon. I. Hyperfine Interactions from ENDOR Measurements

The hyperfine interactions of ${\mathrm{Si}}^{29}$ lattice nuclei with ground-state donor electrons in arsenic-, phosphorus-, and antimony-doped silicon have been measured by electron-nuclear double resonance (ENDOR). Hyperfine constants are reported for each donor for about 20 shells containing a total of about 150 lattice nuclei. About 15 of these shells per donor are reported for the first time; five were reported previously. Our results differ significantly for shells D and E; the other three shells were measured with greater accuracy. The matching of experimental hyperfine tensors to their lattice sites cannot be readily determined. A systematic technique used to analyze the ENDOR spectra is discussed.