ESR observation of temperature-dependent g shifts in submetallic P-doped Si at low temperatures

Submetallic Si:P with dopant concentration of (1.7 ±{} 0.1) ×{} 10¹⁸ cm^-3 has been studied by K-band electron-spin resonance (ESR) in the temperature range 1.6≤T≤300 K. In view of its application as a general ESR g-marker material, accurate g data of the central pair line, i.e., gD, are presented. This reveals that gD changes with T over the whole T range covered, at variance with former belief. Apart from an important influence on its aimed ESR-marker application, this result bears out the complicated nature of the donor spin-ambient interaction, to the modeling of which these data may add further support.