Silver-hydrogen interactions in crystalline silicon

The creation of defects by hydrogen in silver-doped silicon crystals is investigated by deep-level transient spectroscopy. The electrical activity of the substitutional silver impurities can be totally removed due to defect formation with hydrogen atoms. However, this process includes the creation of intermediate electrically active silver-hydrogen complexes. One of the defects, ${\mathrm{A}\mathrm{g}-\mathrm{H}}_1,$ contains one hydrogen atom and introduces three levels in the energy gap. Another electrically active complex is formed by addition of a second hydrogen atom to the ${\mathrm{A}\mathrm{g}-\mathrm{H}}_1$ defect. The Ag-H complexes are stable up to 300–350 °C. The electrically inactive complex includes at least three hydrogen atoms and anneals out at ∼450 °C. The kinetics of the defect transformations are studied in detail, and the distance of silver-hydrogen interaction is estimated to be very close to the lattice parameter.