Diffusion of negatively charged hydrogen in silicon

A new class of experiments is described that provides fresh opportunities for the isolation and measurement of the basic energetic and kinetic parameters determining the behavior of interstitial hydrogen in semiconductors. The technique involves the release of monatomic hydrogen at a sharply defined time and in a known spatial pattern by exposure of dopant-hydrogen complexes in the depletion layer of a Schottky diode to a pulse of minority carriers, and the subsequent time-resolved measurement of the capacitance transient that arises from hydrogen migration, charge-state changes, and complex reformation. The new technique is demonstrated with a measurement of the diffusion coefficient of the ${\mathrm{H}}^{\mathrm{\ensuremath{-}}}$ species in silicon. Also, useful constraints are presented relating to the energies of the hydrogen donor and acceptor levels and the rates of spontaneous charge changes among ${\mathrm{H}}^{+}$, ${\mathrm{H}}^{0}$, and ${\mathrm{H}}^{\mathrm{\ensuremath{-}}}$.