Hydrogen states probed by electron-spin resonance of phosphorus donors in silicon

Hydrogen in phosphorus-doped silicon has been investigated, by monitoring shallow donor P by electron-spin resonance (ESR). Significant broadening in motionally narrowed ESR lines is first observed in Si samples treated with hydrogen plasma. It is found from the donor-concentration dependence that the broadening is caused by the Fermi-contact hyperfine interaction between hydrogen nuclear spins and donor or conduction electrons. Results of annealing hydrogen-passivated Si indicate that an intermediate state of hydrogen with a P donor neighbor is formed via dissociation of P-H complexes at 150–350 °C, and that hydrogen diffuses in n-type Si above 350 °C