Infrared Absorption Study of Zinc-Doped Silicon.

Abstract

AbstractWe report high resolution infrared absorption spectra associated with the deep zinc acceptor in silicon. The optical transitions between ground and bound excited “p-like” states of the neutral helium-like double acceptor Zn0 center have been observed for the first time. The absorption cross section for the hole transition is found to be very small, of the order of 10-17 cm2. Energy spacings of the P3/2 Rydberg series are very similar to the spacings of the group-III acceptors, suggesting that, in spite of the large ground state binding energy, effective mass approximation still applies to the bound excited states. This represents one more case where the strong central cell potential does not significantly disturb the neutral helium-like bound excited states. Similar observations have been made for the less deep neutral double acceptor Be, and for the chalcogens donors S, Se and Te.The optical ionization energy of Zn0/- has been determined to be 2575 cm-1 (319 meV).Two additional sets of absorption lines related to zinc have been observed at 2130 cm-1 and 2758 cm-1. Their origin will be discussed.